Document BRo4oaLJXVo153zyJ77zO5mgJ

THE SOCIETY OF THE PLASTICS INDUSTRY, INC 250 PARK AVENUE NEW YORK, NEW YORK 10017 212/687-2675 December 22, 1967 To: Members, SPI Food Packaging Materials Committee Re: Enclosed "Report on the Role of Plastics in Solid Waste" Gentlemen: Some time ago, the Board of Directors of SPI placed with Battelle Memorial Institute a research program dealing with an extensive study of available records on solid-waste disposal in the United States. This project was embarked upon in view of the fact that of late the subject of refuse disposal has become an area to which the public, and con sequently the nation's lawmakers, have become sensitive. We are certain you will agree that the Board of Directors is extremely foresighted in sponsoring the preparation of this preliminary study at this time. In enclosing a gratus copy of the Report, we wish to point out that additional copies are available at a cost of $2.00 per copy. THE SOCIETY OF THE PLASTICS INDUSTRY, INC. Charles L. Condit Senior Staff Advisor ASI 00000463 ' REPORT ON THE ROLE OF PLASTICS IN SOLID WASTE by M. E. FULMER and R. F. TESTIN BattelleMemorial Institute, Columbus Laboratories 505 King Avenue, Columbus, Ohio 43201 f Sf?S0 Z M prepared for THE SOCIETY OF THE PLASTICS INDUSTRY. INC. ASI 00000464 \ l Battelle is not engaged in research for advertising, sales promotion, or publicity purposes, and this report may not be reproduced in full or in part for such purposes. ftSI 00000465 TABLE OF CONTENTS Introduction...................................................... 1 Summary........................................................ 1 Problems Caused by Plastics in Solid Waste................................................... ,2 Current and Future Role of Plastics in Solid Waste................................................... Overall Solid-Waste Problems................ Present Consumption of Plastics in Packaging and Forecasts of Future Use........................................... Future Role of Plastics in Solid Waste . . 3 3 3 4 Current and Future Disposal Practices. ... 7 Municipal Incinerators............................. 8 Landfills........................................................ 10 Composts......................................................11 Open Dump...................................................11 Household Incinerators................................12 The Relative Importance of Plastics in Planning for Refuse Disposal........................12 Source of Noncombustibles and Heating Value........................................ 12 Source of Pollution..................................... 13 Source of Smoke...........................................15 Utilization of Plastic Materials in Municipal Refuse............................................. 15 Recommendations for Future Work................16 References...........................................................17 APPENDIX A: Present Consumption and Future Usage of Plastic Bottles.....................20 APPENDIX B: Role of Plastics on a Weight Basis..................... 23 APPENDIX C: Government Activity in Solid Waste.....................................................26 APPENDIX D: Fire Hazards Peculiar to the Use of Plastics........................................ 27 LIST OF TABLES Table 1. The Use of Plastics in Packag ing for Selected Years, 19611976.............................................. 4 Table 2. Pounds of Contaminants Dis charged Daily From Domestic Sources in a Metropolitan Area of 100,000 Persons..................... 14 Table 3. Pounds of Contaminants Dis charged Daily From Municipal Sources in a Metropolitan Area of 100,000 Persons Using Vari ous Refuse-Disposal Methods. . . 14 Table A-l. Manufacturers' Shipments and Captive Production of BlowMolded Plastic Bottles by End Use.................................................. 22 Table A-2. Forecast Data on Plastic Bottles............................................. 22 Table A-3. Plastic Bottles According to Type of Resin................................23 Table B-l. Composition and Analysis of an Average Municipal Refuse . . 24 Table B-2. Estimate of Total Plastics in Municipal Refuse -- 1966 ........... 25 Table D-l. Weight Percent Smoke From Various Plastic Products................28 Table D-2. Summary of Decomposition Products of Plastics........................29 Table D-3. The Physiological Effects of Some Gases Which May Occur in Fires...........................................30 LISTS OF FIGURES Figure 1, Total Use of Plastics in Pack aging 1961- 1976........................ 5 ASI 00000466 REPORT ON THE ROLE OF PLASTICS IN SOLID WASTE Introduction Refuse disposal is an area to which the public (and consequently the nation's law makers) has become sensitive. Concern has been expressed about the adequacy of disposal methods from the standpoint of health, sanitation, public welfare, and esthetics. Open dumps are undeniably unsightly, odoriferous, and a potential threat to health. Incinerators are sources of air pollution. Toxic and explosive gases and vapors emanate from landfills under certain conditions. There has been growing public pressure for critical examination of current refuse-disposal practices. Congress gave official recognition to this task when it passed the Waste Disposal Act creating the Office of Solid Wastes* in the Department of Health, Education and Welfare.^1)** One of the first stated goals of this new office was to coordinate its activities with those of industry and to encourage industry to mobilize its knowledge and experience for the solution of solid-waste problems. Accordingly, The Society of the Plastics Industry, Inc. requested Battelle to prepare a report on the effects of plastics in refuse on municipal disposal systems. The objective of this investigation has been to search out literature bearing on the effects of plastics on municipal refuse-disposal systems; determine the present state of knowledge of plastics in refuse; and to forecast future uses of plastics in order to anticipate the future effects of plastics on refuse-disposal systems. Summary A study of available records on solid-waste disposal in the United States uncovered no quantitative evidence of problems uniquely assignable to the presence of plastics. The reasons for this finding are believed to be: (1) there is little quantitative information on solid-waste processing, (2) the percentage of plastics in municipal refuse is low (estimated at 1.5 percent), and (3) there are numerous other materials in municipal refuse whose properties could create problems under certain circumstances. The concentration of plastics in municipal refuse is expected to more than double during the next decade, requiring an assessment of possible future problems. Potential problems of plastics in municipal refuse are tied to the method of disposal. Open dump ing, if accompanied by uncontrolled burning, creates problems of smoke and odor which are, however, not uniquely traceable to plastics. This method of disposal is undesirable *Now designated "The Solid Waste Program " ** References are at the end of the report (5tSI 00000467 for a number of reasons, and is expected to diminish significantly. In sanitary landfills, plastics may produce a slight decrease in density, but are not considered a source of pollution. In composting, plastics may affect the appearance of the end product, but are not expected to affect its properties in any other way. The major future problem area associated with increased use of plastics is expected to be connected with disposal by incineration. Intermittent sharp rises in plastics concentration in an incinerator feed could lead to clogging problems with its associated difficulties, caused by the relatively low melting points of a number of plastics. Unless large quan tities of industrial plastic waste are included in municipal refuse without blending, this is not a very likely cause of trouble. A more likely future problem is associated with the incineration of halogen-bearing plastics, such as polyvinyl chloride, or polymers contain ing flame inhibitors. The hydrogen halides emitted in this process are known to corrode metallic incinerator components and may also create an air-pollution hazard. There are no quantitative data to document the magnitude of the pollution hazard; estimates based on the total quantity of polyvinyl chloride plastics believed to enter municipal refuse suggest that incinerator stack concentration of hydrogen chloride from this source* may approach toxicological limits. Based on these same toxicological limits, total quantities of HC1 in the urban atmosphere are low, and polyvinyl chloride is only one of many sources. Current emphasis on the more subtle effects of pollutants, which may include investigation of subclinical effects, could in the future lead to the establishment of stand ards for hydrogen halide emissions which may be lower than the presently accepted toxicological limits. It thus appears that attention should be focused on potential problems connected with incineration of refuse with particular emphasis on the generation of hydrogen halides. Problems Caused By Plastics in Solid Waste Very few references to problems created by plastics in municipal refuse-disposal sys tems were found in the literature. It was felt there were two reasons for this: (1) plastics make up only a small proportion of municipal refuse and so their effects on disposal systems, if any, are considerably diluted by the effects produced by other constituents and (2) the entire field of refuse disposal has been neglected up to the present time and this is reflected in the scarcity of literature on this subject. Literature on plastics disposal is limited almost entirely to descriptions of industrial waste-disposal systems^2'3'4'5'6'7'8) where the waste is principally or wholly plastics and, here, the method of disposal is generally burning or incineration. Although this study did not cover industrial disposal methods it was felt that some reference to the fact that indus try has had problems in burning and incinerating plastics was in order. These problems were described: (1) Clogging of incinerators due to melting (2) Production of black smoke when burned at low temperatures * It should be pointed out that this is only one source of HC1 emission; coal, for instance, accounts for approximately twice as much total HCI in the. atmosphere. 2 ASI 00000468 i (3) Corrosion of equipment by gaseous products of combustion (4) Production of physiologically undesirable combustion products (5) Generation of offensive odors when burned at low temperatures. The subject was discussed with sanitary engineers of the Ohio Health Department and this conversation did reveal one problem associated with plastics in municipal refuse. This was the problem of resistance to compression and pulverization of some plastics in land fill operations. The literature search did not produce any additional information on this problem. The general consensus from the literature work and from discussions such as that noted above indicates that, at this time, plastics play a nuisance role in waste disposal, but do not significantly affect disposal-system operation. The remainder of this report is devoted to examination of current and future uses of plastics by consumers in order to determine the future role of plastics (as compared to other packaging materials) in the overall solid-waste picture. Current and Future Role of Plastics in Solid Waste OVERALL SOLID-WASTE PROBLEMS Solid wastes from cities, industries, and agriculture constitute one of the major cate gories of land pollution. Several recent publications!9-10) indicate, to some degree, the current and future magnitude of the solid-waste problem in the United States. The total amount of refuse produced annually in this country is approximately 340 billion pounds and this figure is expected to increase to 450 billion pounds or more by the end of 1976 Of these overall totals, municipal refuse is the largest single contributor with a current (1966) total of approximately 250 billion pounds. PRESENT CONSUMPTION OF PLASTICS IN PACKAGING AND FORECASTS OF FUTURE USE As an aid to evaluating the present and future roles of plastics in solid waste, fore casts of plastics-packaging usage have been made at three levels to represent "low", "high", and "best" estimates. Although these rough forecasts were produced with only a limited effort, they allow assessment of the magnitude of problems that might be caused by plastics packaging under several sets of assumptions.* Table 1 presents estimates of plastics usage by weight for packaging applications for selected years in the 1961 to 1976 period. Total plastics utilization for packaging is also shown graphically in Figure 1. The large spread between the "high" and "best" (or most realistic) estimates reflects the degree of uncertainty concerning the future use of plastics -- particularly plastic bottles. * These estimates as well as others in the report were made to define the current and future role of plastics in solid waste. Within this framework they are adequate, but they should not be used out of context to relate to subjects other than solid-waste production. ASI 00000469 TABLE 1. THE USE OF PLASTICS IN PACKAGING FOR SELECTED YEARS, 1961-1976 (Millions of Pounds) 1961 Plastic bottles..................................... .. 125 Other rigid plastic containers, closures, flexible tubes, etc......... .. 175 Plastic film and sheet'3!................ .. 410 Total use of plastics as packaging substrates................... .. 710 Plastic coatings and adhesives.... . 250 Grand total......................................... . 960 1966 300 600 900 1800 500 2300 Low 500 800 1300 2600 650 3250 1971 Best 900 1000 1600 3500 750 4250 High . Low 1900 800 1300 2100 1200 1700 5300 850 6150 3700 800 4500 1976 Best 1800 1500 2300 5600 1000 6600 High 3000 2000 3000 8000 1200 9200 Source1. Rartolle estimates based on published information and industr\ contacts (a) Excluding thermoformed sheet which is included under "other rigid plastic containers". The future outlook for packaging usage of blow-molded containers is discussed further in Appendix A. FUTURE ROLE OF PLASTICS IN SOLID WASTE On the basis of forecasts of future plastic use and examination of the current com position of solid waste, it is possible to make some predictions about the effects of plastics in municipal refuse-disposal systems during the next decade. Role of Plastics on a Weight Basis A review of municipal waste studies and plastics production figures!11-12-13-14! does not provide sufficient information to directly determine the characteristics of plastics in municipal refuse at the present time. These characteristics were estimated using available data (Appendix B). As indicated by Appendix B, the probable major constituents of plastic and solid waste are: polyethylene (38 percent), polyvinyl chloride (32 percent) and polystyrene (21 percent). The total amount of plastic waste disposed of in refuse currently is 3-1/4 billion pounds per year or about 1.5 percent of the total amount of refuse generated. As discussed in the previous section, Appendix A, and the literature (References 15-21) one of the most dynamic markets for plastics at the present time is the packaging industry, especially rigid plastics such as bottles. It has been predicted that the total volume of packaging will increase by 50 percent in the next 10 years and that the plastics portion will double from 1 to 2 percent in that period.!22-23! The 1976 "best estimate" of total packaging use discussed in the last section was 6.6 billion pounds. By 1976 total refuse produced will be about 450 billion pounds annually.!10! If the current municipal percentage of total refuse produced remains constant, municipal refuse will reach 330 billion pounds annually at this time. If the worst case is assumed, in which all packaging materials enter the municipal refuse system, the proportion of plastics in refuse from packaging alone could be as high as 2 percent, which is more than the cur rent input of plastics from all sources. An estimate of the total plastic in solid waste in 1976 can be estimated in a manner similar to procedures used in Appendix B. For example, if packaging production figures (Table 1) are taken as a guide to future plastic waste, the amount of plastics in waste 4 ASI 00000470 9 3 < ico .2 m High estimate // Best / estimate / // Low estimate/ 1961 1966 1971 1976 Year A- 55838 FIGURE 1. TOTAL USE OF PLASTICS IN PACKAGING, 1961 - 1976 5 ASI 00000471 will increase by a factor of 2.9 in the next 10 years. Overall solid-waste production is expected to increase about 30 percent in the same period. Using these figures, 1976 plastic-weight percentage in municipal waste is estimated to be percent of the total municipal refuse generated at that time. This corresponds to almost 11 billion pounds of plastic waste annually. These figures are based upon increases in plastic pro duction since no real guidelines are available to relate percentage increases in plastic production to increases in waste plastics. As such, they can be considered conservative or "high" estimates. The changes in composition of refuse based on forecasts of consumer uses may be overshadowed by those produced if industrial wastes are accepted in municipal disposal systems in the future. At the present time, industry seeks its own best solutions. If, in the future, municipalities accept the responsibility for disposing of industrial solids, the pro portion of plastics in refuse could increase significantly. The quantity of refuse from industry is estimated to be about 25 percent of the total amount of solid-waste gener ated/10* The plastics content is, however, much higher and at the present time it is be lieved to average between 2 and 15 percent(24) with the amounts of synthetic materials continuing to increase. Should industrial waste high in plastics be incinerated with domes tic refuse, it would be important to mix the two thoroughly to obtain an equalization of fuel properties and to maintain the lowest possible emission of harmful incineration prod ucts such as HCl. Present refuse-handling practices make no provision for any blending operation. Role of Plastics on a Volume Basis An increased proportion by weight of rigid plastic containers in refuse will increase the volume per unit weight of refuse. Penetration of the coated paper and returnable glass markets will result in an increase in volume of refuse per capita. Penetration of the glass market will change this volume only to the extent that the returnable containers are dis placed by nonretumable plastic containers. In order to determine how significant the volume increase would be if rigid plastic containers were substituted for coated plastic and returnable containers, estimates were made for the volume effects of predicted plastics penetration into the milk-container market. In order to make this estimate the following assumptions were made: (1) The total number of milk-packaging units will remain unchanged (2) All plastic milk containers produced are delivered to municipal refuse systems (3) Current coated plastic and returnable glass bottles contribute negligible volume to municipal-refuse systems (4) The density of municipal refuse is 300 lb/cu yd. (This figure is very approxi mate. The density of refuse varies from 100 to 1500 lb/cu yd depending upon composition. The weight per unit volume of refuse has decreased from 1100 lb/ cu yd to as low as 160 lb/cu yd over the past 50 years). Based on the data presented in Appendix A, the best estimate of plastic-milk-bottle penetration by 1976 is 50 percent of the gallon and half-gallon containers. This represents a total potential volume increase of 0.37 billion ft3/year. A total municipal refuse pro duction of 330 billion pounds in 1976 is equivalent to a volume production of 30 billion 6 ASI 00000472 ft3/year. Therefore, a potential increase in municipal refuse volume of about 1.2 percent could be possible by plastic penetration of the milk-packaging market. This potential volume increase does not appear to be significant since some compac tion of plastic bottles will occur, particularly where compacting garbage trucks are used for hauling and incineration for ultimate disposal. Furthermore, in refuse disposal by incineration, a lighter, drier material may actually aid in combustion. General Effects Widespread use of rigid containers will also result in a change in the relative amounts of the plastics used for containers, a change that will also be reflected in the composition of municipal refuse. PVC is a strong contender in the blown-bottle area and in nearly all areas where glass is used now. A recent FDA regulation!25) regarding use of a PVC-PE copolymer for food-contact applications indicates that the fraction of PVC in packaging will probably increase this year and will continue to increase substantially over the next few years. By 1976, PVC could constitute as much as 1 percent of municipal refuse by weight. This increase has already been observed in Germany where PVC applications are much more widespread than in the United States. The proportion of PVC in German refuse varies between 1 and 3 percent at the present time.!26) This trend may be affected in either direction by new uses for plastic materials or new methods of packaging such as the bottle pack system.!27) The potential effect on refuse of entirely new uses for plastics or new methods of fabricating packages is outside the scope of this study. Current and Future Disposal Practices The degree to which variations in the characteristics of refuse affect municipal refuse systems depends largely on the method of disposal used. There are four disposal systems in common use today --open dumps, composts, landfills, and incinerators. Open dumps, with and without burning, have been judged unsuitable for present-day living in urban areas and are gradually being replaced by landfills and large incinerators. Landfill is favored at the present time, but landfills come to an end when suitable disposal land is no longer available. This is already happening in some areas and it appears that incin eration will become the major method of disposal. Milwaukee, for instance, is on the verge of a major shift to incineration forced by a shortage of dump sites within 30 miles. Incineration cuts down the volume of raw refuse to about one-third its original volume. New developments in refuse disposal could change this picture completely. Most of the cost of refuse disposal --between 75 and 80 percent--is due to the cost of collection and transportation of refuse from the point of origin to the disposal plant. Reduction in quan tity (both volume and weight) of refuse generated would result in a two-fold cost reduction due to (1) reduced cost of pickup and transportation and (2) reduced cost of disposal. There are at least two methods of reducing refuse quantities that are technically feasible. One is an improved household incinerator. The other is a shredder and grinder that reduces all combustibles (paper, plastics) to a size suitable for disposal in the sewage system. These ground combustibles would be removed with the sludge in the sewagetreatment plant. The physical properties and the high heat of combustion of these mate rials could aid in the drying and incineration of the sludge. 7 ASI 00000473 MUNICIPAL INCINERATORS Incinerating Characteristics of Plastic Materials The need for fire-resistant plastic materials and the previously discussed hazards of fire, smoke, and toxic gases from smouldering plastics have a direct bearing on the dis posal of plastic refuse by incineration. In short, whatever is done to impart fire resistance will also make the material more difficult to incinerate. Moreover, the need for flame retardance will, undoubtedly, continue to have priority over factors involved in the disposal of plastic refuse. Many of the plastic materials in common use today, such as polyethylene, do not contain chlorine or other flame retardants. These materials are essentially hydrocarbons or carbon-containing compounds with fairly high heats of combustion which can be burned with air under suitable conditions of temperature, turbulence, and time to give gaseous products consisting almost entirely of .carbon dioxide, water vapor, nitrogen, and excess oxygen. Products of incomplete combustion, such as traces of carbon monoxide and hydrogen or other organic gases, as well as smoke and soot, can usually be held to acceptable limits when sufficient other combustible refuse accompanies the plastic refuse in an incinerator. If a comparatively large stratified mass of plastics enters an incinerator, the mass first softens and then melts and flows; this causes difficulty in grate-type incinerators. At the same time, comparatively large volumes of combustible gases are evolved from the heated mass of plastic, and the combustion air, which is normally supplied for a less volatile refuse, may be insufficient in quantity and turbulence to provide smoke-free combination. Smoke and soot from plastics and rubber or tarry materials which escapes the primary combustion zone can persist to some degree even when exposed later in the incinerator to excess air and otherwise adequate afterburner temperatures of 1200 to 1400 F. The problem in designing as well as operating an incinerator involves compromises in air distribution, turbulence, excess air, and peak temperature in favor of an average refuse composition and steady feed rate rather than for the extremes in refuse charac teristics or for intermittent batch feeding. In this respect, small batch-operated domestic incinerators are more likely to be operated under extreme conditions than large, contin uously-fed municipal incinerators, simply because the larger inventory of refuse in the combustion chamber and in the storage pit with the large units provides a better aver aging effect on composition, and a greater tolerance for large range in size distribution.* The start-up periods, and the periods following charging in batch-operated inciner ators, represent sudden changes which upset the conditions needed for good steady com bustion. Firing of auxiliary fuel prior to startup is helpful in preheating refractory combustion chambers, but the practice of batch feeding should be limited to small, frequent charges of plastics which approaches continuous feed. Shredding or reducing the size of plastic refuse would also assist in this respect. Incineration of Materials Containing Chlorine The presence of halogens (chlorine or bromine) in plastics, such as polyvinyl chloride, and in flame-retarding plasticizers and other additives presents three problems in the disposal of these materials by incineration: *As noted previously, this situation could deteriorate if industrial refuse is added to the municipal load, by increasing the probability of large masses of plastic waste entering the feed stream. 8 00000474 ASI (1) Combustion is inhibited by the halogen gases; thus, more vigorous turbulence is needed to take care of the increased tendency for production of smoke. (2) The chlorine or bromine appears in the combustion products as gaseous hydro gen chloride (HC1) or hydrogen bromide (HBr) which can attack metals in the incinerator. (3) The emission of HC1 and HBr contributes to air pollution. Much of the available data center around chlorine problems with PVC and the re mainder of the discussion is limited to this aspect of the problem. ** Of the previously mentioned total plastic content of 1.5 percent in present municipal refuse in the United States, about one-third is polyvinyl chloride. A report in 1966, based on incinerator practice in Germany/28! states that: "One of the most used plastics is polyvinyl chloride (PVC). Its proportion in household refuse is today between 1 and 3 percent. The chlorine content of this material, which is difficult to burn, is about 50 percent and when heated over 446 F, it appears as hydrochloric acid. Slagging and tube corrosion occur due to the formation of sodium chloride and direct attack by hydrochloric acid. If the furnace temperature is too low and secondary combustion is inadequate, PVC bums with intense soot development. The soot absorbs hydrochloric acid and produces con siderable corrosion when deposited on tube walls." The tube walls referred to in the above report are water-filled steel tubes of the boiler where heat is recovered as high-pressure steam at about 1000 F, as is done in most large German incinerators. During a visit to several German incinerator plants in 1966 by a member of the Battelle staff, their experience with corrosion was discussed. Corrosion troubles have occurred in most, but not all, of the boiler plants burning municipal refuse; surprisingly, one plant which incinerates chemical wastes with much higher chlorine content than municipal refuse had not had trouble from boiler-tube corrosion. The causes of corrosion did not appear to be well established; some put the blame on chlorides because the sulfur content of municipal refuse is low, others believe that poor combustion and reducing conditions in many grate furnaces volatilize whatever alkali sulfates are present, which then deposit and attack the tubes. In most cases when the steam temperature is over 1000 F, corrosion occurs, presumably because the tube surfaces are then hot enough to promote chemical attack by some of the constituents of the ash. While most municipal incinerators now operating in the United States are refractory structures, which are quite resistant to hydrogen-chloride gas, there will be an inevitable trend toward designs with water-cooled metal tubes in the walls of the combustion cham ber. The incentive for this trend is not so much concerned with the obvious recovery of waste heat, but is intended mainly to (1) permit higher combustion-zone temperatures so that the volume of excess air can be reduced and (2) obtain lower exit-gas temperatures to permit the use of dry-type dust collectors for pollution control. Corrosion could, there fore, become more of a problem with large water-cooled incinerators as they are intro duced in the United States and as the PVC content of municipal refuse continues to increase. In the case of small-size incinerators, such as domestic units, some of their metal surfaces are usually exposed to the combustion products; at times these surfaces are below the dew-point temperature where the hydrochloric acid formed will attack the metal. This ** It is recognized that as the use of bromine-bearing fire-retardant plastics increases, bromine may also be a problem since bromine compounds are generally more corrosive and toxic than chlorides. 9 j f 1 ASI 00000475 type of corrosion attack from HC1 has been reported^29) in other combustion equipment which operates in areas where the incoming combustion air was contaminated with trace concentrations of halogenated hydrocarbon vapors, in the range of from 5 to 23 ppm by volume, from dry-cleaning fluids and aerosol-can propellants. Perhaps the most vexing aspect concerned with the incineration of chlorine-containing plastic refuse is the air-pollution potential of HC1 emissions. Presently there are no airpollution regulations on HC1 in the United States, but the growing emphasis on air pollution cannot be ignored. In England and Canada, current regulations^30^ limit the emission of HC1 from stacks and chimneys to a maximum concentration of 0.2 grain per cu. ft. of gas (290 ppm HC1 by volume). The Threshold Limit Value* (Probable Safe Concentration), within which it is felt that workers may be repeatedly exposed for an 8-hour working day without injury to health, is 5 ppm by volume for HC1. Thus, a dilution of about 60 to 1, which can be easily obtained from a tall stack, is needed before the stack gases would be diluted to the TLV. If and when any air-quality criteria are established for HC1, judging from the recent trend with SO2, the criterion for urban atmospheres is likely to be 0.1 to 0.2 ppm for a 24-hour average. Calculations were made which show that an emission of 290 ppm of HC1 from an incinerator would result if the refuse contains 0.54 percent by weight of PVC. This calcu lation was based on incineration of a typical refuse containing 20-percent moisture and 20-percent ash and noncombustibles, using 150-percent excess air for combustion. Thus, it appears that the current PVC content in municipal refuse (approximately 0.5 percent) may already be on the borderline of air-pollution potential as judged by HC1 emission regulations in England gnd Canada. However, as pointed out in the following section, chlorides from combustion of plastics are only one of several sources of chlorides in air. The fact that the National Air Sampling Network and the continuous Air Monitoring Programs of the U.S. Public Health Service both measure nitrates and sulfates, but not chlorides, indicates that the latter are not yet receiving much attention as general pollutants. The control and abatement of HC1, like SO2 and nitrogen oxides, in exhaust gases will probably be based on wet scrubbing, absorption, or adsorption, which are costly compared to abatement methods for dust and fly ash. LANDFILLS(31'32'33-34-35> Sanitary landfilling has been defined by the American Society of Civil Engineers as "a method of disposing of refuse on land without creating nuisances or hazards to public health or safety, by utilizing the principles of engineering to confine the refuse to the smallest practical areas, to reduce it to the smallest possible volume, and to cover it with a layer of earth at the conclusion of each day's operation or at such more frequent intervals as may be necessary." Sanitary landfilling is the least-expensive acceptable refuse disposal method in use today. There are three problems associated with landfills. One is the high probability of water pollution. Another is the toxic and explosive gases that are potential products of refuse decomposition. The third is land pollution which differs from air or water pollution in that the polluting material remains in place for long periods of time unless moved, burned, washed away, or otherwise destroyed. `Established by the American Conference of Government Industrial Hygienists. 10 ACT 00000476 Plastics in landfills are not considered to contribute to air or water pollution. The California Water Pollution Control Region No. 4 which has classified disposal sites per mits plastics in the Class III site which "is so located as to afford little or no protection to useable waters of the state." One objection to plastics in landfill operations is that some difficulty is experienced in compressing rigid containers. The dozers presently used in landfills do not exert suffi cient pressure to rupture these containers. Much of the volume displaced by these contain ers is air. This increases the cost and lowers the quality of the landfill. COMPOSTS^36-37-38'39'40-41) Composts are used extensively in Europe for disposal of municipal refuse but only to a limited degree in the United States. A new plant in St. Petersburg, Florida, that can process up to 105 tons of refuse a day has stimulated renewed, interest in this process. If operating results are favorable, composting may be adopted by other municipalities in this country. Refuse is generally pretreated to remove metal objects and ground prior to compost ing. The composting process is a biological digestion process. The product of digestion can be used as a soil conditioner. Plastics have been known to pass through the system without being thoroughly disintegrated and thus mar the appearance of the final product somewhat The pulverizing equipment used in composting systems does not do a reliable job of disintegrating some materials such as sheet plastics and they occasionally appear in unsegmented form in the compost product. OPEN DUMP Open dumps have been judged unsuitable as a method of municipal refuse disposal. Although currently the most commonly used methods of disposal, it is expected their use will decrease drastically in the next few years, particularly in urban areas. Burning occurs in most dump areas, either deliberately to reduce the volume of refuse or accidentally as a result of the combustible nature of the refuse materials. As a result, dumps pollute not only the land and water but also the air. The pollution created by burning plastics is indistinguishable from the pollution produced by many other components of the refuse. Many components of refuse --rags, rubber, leather, plastic--cause offensive odors and many, particularly chlorinated compounds such as chlorinated rubber and PVC, produce dense black smoke when burned at low temperature. Some of the gases and vapors evolved (such as HC1) are also irritants and contribute in this manner to the overall air-pollution problem. Although chlorinated plastics produce black smoke, they generally are diluted with other components of refuse and the smoke produced is diluted proportionally by the products of combustion of these other constituents. The dense plumes of black smoke often seen emanating from dumps can usually be traced to large burning articles such as tires. The rubber that went into tires alone in 1965 amounted to 600 million pounds and most of these eventually land in dump heaps. 11 ASI 00000477 HOUSEHOLD INCINERATORS There are two broad types of domestic incinerators: outdoor and indoor. The outdoor burners are generally not much better than small-scale open burning dumps. Combustion temperature and the amount of air cannot be regulated effectively or economically, and the smoke, odors, and fly ash produced are a hazard to nearby buildings and are obnoxious to inhabitants of these buildings. Like open dumps, outdoor incinerators are expected to be eliminated as a method for refuse disposal. The contribution of plastics to the overall emission problem is in general the same as described in the section on open dumps. Indoor incinerators can be classified broadly as those that bum refuse without use of auxiliary fuel and those that use auxiliary fuel. Home incinerators operated without auxiliary fuel work much like outdoor incinera tors. The only advantage is that smoke and odors and irritants are discharged from the top of the house chimney and are thus substantially diluted. The concentration of HCl produced at street level from emissions of burning refuse containing 0.15 percent chlorine would be about 0.005 ppmd42) The most widely used home incinerators are those using gas as an auxiliary fuel. It is possible to regulate combustion temperature and the amount of air needed for combus tion so that emissions are not smoky or odorous. After-burners have been developed that insure that the emission is held at the temperatures that are needed to control smoke and odors, i.e., 1300 F or more. Gases such as HCl, HF, SO2 and oxides of nitrogen are not removed in these units. Their removal requires additional treatment such as absorp tion, adsorption, or scrubbing procedures which may not be practical on the small scale of household units. It should be noted in connection with domestic incinerators that if they are not ade quately vented, the burning of PVC may constitute a toxic hazard although the HCl produced gives a good warning signal by irritation, i43) The Relative Importance of Plastics in Planning for Refuse Disposal Three of the most important characteristics of refuse to be considered in planning a disposal system are (1) percent noncombustibles and heating value, (2) polluting effects on air, water, and land, and (3) smoke properties. SOURCE OF NONCOMBUSTIBLES AND HEATING VALUE The most recently published data on composition and analysis of municipal refuse are shown in Table B-l (Appendix B).(44) Since these data were collected in 1963, the percent figures have changed somewhat. Plastics have probably increased and the per centage of other components has also fluctuated. The literature does not indicate that any 12 ASI 00000478 variations have been very sizeable as a percentage of the total, however, and the 0f these v table wip be useci as a basis for comparing the plastics in refuse with all other components. The noncombustibles in refuse amount to 31 percent, i.e., an "average" ton of refuse 1Q nounds of noncombustibles. The metallics, glass, and ceramics contribute contains oiu 5p12 pound,s of, t,,hi.s a..m....o..u...n_t_.__M__o__s_t__o_f__t_h_e___r_e_m__a_i_n_d__e_r__i_s__c_o__ni_trib_u_t_e_d___b_y___p_a__per g3 Pe^^g sweepings (12 pounds), household dirt (14 pounds), unclassified (6 pounds). (p4la5stPicosuncont'ributte 00.3g2o2o ppeerrcceenntt of the total noncombustibles or 2 pounds per ton of refuse. The total heating value of refuse on a dry basis averages 6200 Btu/lb. Of this, 2.3 t is contributed by plastics. The prinicpal source of heating value is paper which contributes 65 percent of the total. SOURCE OF POLLUTION Plastics do not appear to have any potential as land or water pollutants. As with other combustibles, gaseous emissions and smoke from burning plastics will contaminate the atmosphere if not controlled. Compared with other current sources of municipal and domestic air pollution, the amount contributed by plastics with uncon trolled burning is small. The pounds of contaminants discharged daily from domestic sources (fuel and incin eration) and the pounds of contaminants discharged daily from municipal sources (incineration, burning dumps, sanitary landfill) in a metropolitan area of 100,000 persons are shown in Tables 2 and 3, respectively.!43) The principal pollutants are oxides of sulfur and nitrogen, H2S, NH3, aldehydes, organic acids and solids. The prinicpal gaseous contaminants from burning of fuels are the sulfur oxides/45! Organics are the main gaseous contaminant from refuse disposal. The minor role that plastics play in the pollution problem is indicated by the fact that HC1 is either not present in detectable amounts or not measured in the emissions from refuse disposal processes (Table 3). Although coal contains only a small amount of chlorine (up to 0.7 percent), it is used in such large quantities that it is the major source of HC1 pollution. In 1965, 550,000 tons of coal was used in the United States. Assuming 0.1 percent was evolved as HC1, the total pollutional load was 1.1 million pounds of HC1. The total pounds of chlorinated plastics produced in 1965 (1.837 billion) multiplied by the average weight percent evolved as HC1 (35 percent) gives the total amount of HC1 pollution from this source (0.63 billion). Assuming the entire annual production of chlorinated plastics were burned or incinerated, the pollutional load would be about half that of coal. Similar computations could be made for HC1 in industrial emissions from the petroleum-products industry; paper and allied industries; stone, clay, and glass manu facture; food and kindred products industry; chemical and allied products industry; gray iron foundries; primary metal industry; nonferrous foundries; plants using fuel oil; and the metal-finishing industry. Some data have been presented which show that these emis sions cause a measurable HC1 concentration in many municipalities/46'47! The concentra tion of HC1 in the air of various cities has been found to vary between 0.010 and 0.058 ppm/35) Chlorine has not, however, been detected in the general atmosphere |Of the Los Angeles Basin, although it is released from various operations. At present it is not sus pected of having appreciable effects on smog characteristics/4) 13 ASI 00000479 TABLE 2. POUNDS OF CONTAMINANTS DISCHARGED DAILY FROM DOMESTIC SOURCES IN A METROPOLITAN AREA OF 100,000 PERSONS Pounds per Day per 100,000 Persons Using Each Category of Heating and Refuse Disvosal Fuel -- Domestic Heating Domestic Incineration Principal Contaminants Coal, 1000 tons Backyard Household Apartment Oil Gas Burning Incinerator Incinerator SOx............................ NOx........................... HoS............................ NH3........................... HC1........................... Aldehydes.................. Organics Organic acids............ Solids........................ .... 42,000 8,000 2,000 2,000 2,000 20,000 30,000 200,000 17,000 6,000 500 800 500 800 4,000 12,000 800 0.4 6 0.1 0.3 0.3 1 1 1 0.1 180 90 - 345 - 600 42,000 225 3,400 1 1,150 - 8,400 12,000 1,900 16,500 12 30 24 24 72 1,800 4,800 4,000 Total of above categories.......... .... 307,000 42,400 10 46,800 40,000 10,700 Source: Reference 43 Notes: SOx --oxides of sulfur-- S02 and SO3. N Ox -- oxides of nitrogen. Aldehydes measured as formaldehyde. Organic acids measured as acetic acid. Total includes only above categories and does not imply total contamination in the ambient atmosphere. The contributions listed for household incinerators are considered high. General use of high gas input domestic units with after-burners would significantly lower contributions from this source. TABLE 3. POUNDS OF CONTAMINANTS DISCHARGED DAILY FROM MUNICIPAL SOURCES IN A METROPOLITAN AREA OF 100,000 PERSONS USING VARIOUS REFUSE-DISPOSAL METHODS Principal Contaminants SOx.......................................... NOx......................................... H2S.......................................... nh3......................................... Aldehydes................................ Organics.................................. Organic acids.......................... Solids...................................... Total of above categories Pounds per Day per 100,000 Persons Using Each Category of Refuse Disposal Incineration Burning Dumas Sanitary Land-Fill 290 320 -* 45 168 210 90 3.450 180 90 - 345 600 42,000 225 7,000 - Trace Trace Trace Variable(a) 4,570 50,400 Low Source: Reference 43 (a) Depends on amount of ashes being placed and amount of dust In cover material. Can be controlled. There are at least three standards in existence used to limit discharges of HC1. The first, Works Regulation Act of Great Britain passed in 1863, specifies a 95 percent recov ery of such emissions and an amendment to this Act in 1874 limits the discharge of HC1, to 0.2 grains per cubic foot (i.e., 280 ppm by volume) of flue gas before dilution 14 ASI 00000480 with other stack gas or air.*40) The second, the emission-limiting values for chlorine that have been adopted by Germany titled "Technical Regulations for Air Pollution Control," are as follows: Standard: 0.12 x 10 "3 grains Cl/cu ft air (0.17 ppm) Limiting: 0.009 grains Cl/cu ft air 1/2 hour within 8 hours(26,28) (12.6 ppm). The third, the Soviet standards, are ambient-air quality standards instead of emission standards. The MAC outdoors in populated areas is 0.06 ppm of chlorine at any one time, and 0.018 ppm is the average maximum concentration in any 24 hours!43 50) The Public Health Service is currently developing air-quality criteria/51) These criteria are to be developed whenever it is deemed that an air-pollution agent is present in the air in sufficient quantities to produce effects harmful to the health or welfare of people. At the present time criteria are being developed for oxides of sulfur and photochemical oxidants. The next criteria scheduled to be developed are those for carbon monoxide and oxides of nitrogen. There is at present no indication when HC1 criteria might be considered. SOURCE OF SMOKE<52 53 54 55> The smoke produced from plastics varies in characteristics, depending on the material burned. The smoke from polymethyl methacrylate is less dense than that from burning red oak wood. Polyvinyl chloride, and polystyrene plastics, on the other hand, produce dense black smoke (such as that produced by burning rubber tires) as do many plastics which contain additives to make them self-extinguishing. The obvious method of removing smoke discharges is to completely oxidize all the material in the smoke. This kind of control can be effected at central incinerators but is not applicable to backyard or opendump burning. The smoke produced at these sites is unsightly, can have adverse effects on crops, and discolors buildings, fabrics, and other objects. Utilization of Plastic Materials in Municipal Refuse(56'57'58) The only use that is made of plastic materials in refuse at the present time is for recovery of their heating value. Even in countries such as Germany, where the proportion of plastics is considerably higher than in the United States, the only recovery that is practiced is heat recovery. There is a reuse for thermoplastics in plastic manufacturing processes. The principal difficulty facing reuse of plastics in municipal refuse is the problem of separating the thermoplastics from the other constituents of the refuse. The cost of hand sorting is pro hibitive in the United States. No methods of machine separation are described in the literature. At present the only remotely feasible system appears to be sorting at the source, i.e., by the householder. This has not proved practicable for the most part. The penalty for not sorting has usually been to stop pickup service. This results in more and more refuse being scattered by roadsides. 15 ASI 00000481 The problems of utilizing thermosets in waste is even more difficult. Thermosets, even if isolated from the rest of the refuse, cannot generally be reused in plastics manufacture. The proportion of thermosets in waste plastics in refuse is extremely small --in the order of 5 percent --and even this proportion appears to be decreasing. Recommendations for Future Work During this study it became apparent that additional work is needed in several areas of solid-waste technology. In particular, two areas stand out as being particularly impor tant to the future role of plastics in solid waste. The first of these relates to the need for more detailed reporting systems for all cate gories of materials and would entail a.relatively detailed economic analysis of the future growth of plastics of all kinds in solid waste. Some preliminary estimates were included as part of the current study, but the lack of literature data warrants a more detailed study. Particular emphasis should be placed on the total growth of plastics in solid waste, the predicted increase of potential problem cases such as halogen-containing polymers, and the potential intrusion of industrial waste-bearing large amounts of plastics into the municipal waste-treatment system. It must be emphasized that while all of these points were touched on as part of the current study, time and cost allocations precluded any detailed work on the economic evaluation and future growth patterns. Also, a continuing program of literature surveillance and compilation should be conducted. As brought out in this study, very little past literature on plastics in municipal waste was found. This lack has extended generally through the entire solid-waste field. However, literature on solid waste in general is increasing at a phenomenal rate and it is anticipated that work on potential solid-waste problem areas will likewise show a sharp increase. Battelle believes that the importance of a continuing program to survey and analyze the current literature cannot be emphasized too strongly in order to determine courses of action to forestall future problems. These first two activities should properly be sponsored by joint action of those tech nical and trade societies representing materials, methods of disposal, and concerned government and municipal bodies. A third recommended area of future work is in the incinerator area since incineration is expected to play a major role in future solid waste processing. Knowledge about the effect of large variations in concentration of certain non-combustibles (such as aluminum and glass) and selected combustibles on incinerator performance is either lacking or insufficient. Plastics are among these combustibles, where more knowledge about possible inefficient combustion, as well as clogging and other possible damage is needed. Finally, during the course of this study a great many particular unknown areas in the plastics-solid waste area were uncovered. Many of these relate to the incineratorwaste disposal systems area and could in themselves form the basis for further study to define corrective action. These areas include: Decomposition Products From Incinerated Plastics and Other Materials The physiological synergistic effects, if any, of gaseous products of refuse com bustion such as HC1 and SO2 16 00000482  The best methods for removing HCi from stack gases (SO2 is under intense study now as a major product of oil and coal burning.) The composition of the reaction products from the combustion of plastics on a quantitative basis. Plastics-Incinerator Relationships The products of plastics combustion existing at the temperatures at which municipal incinerators operate (are materials synthesized as well as degraded?) The conditions that are imposed in present and improved incinerator design for various concentrations of halogen-containing plastics in refuse Household incinerator designs that will be generally acceptable to air pollution control authorities as well as to householders. The Release of Smoke The time-temperature relationships for destruction of smoke from plastics Definition of the products of reactions that are induced when large excesses of secondary air are used in incinerators to control smoke. Methods of Handling Plastics in Municipal Trash Economic separation of plastics, alone, or in combination with other selected constituents of municipal refuse Grinder and shredder designs which will reduce combustibles (plastics, paper) to a form that can be handled more effectively in incineration, sewerage or other dis posal systems. References (1) Solid Waste Disposal Act, Public Law 89-272, 89th Congress, S. 306, October 20, 1965. (2) Frankel, Joseph I., "Incineration of Process Wastes," Chemical Engineering 73 (18), 91-96 (1966). (3) Peskin, Leonard C-, "The Development of Open Pit Incinerators for Solid Waste Disposal," Journal of the Air Pollution Control Association, 16 (10), 550-551 (1966). (4) Lipsett, Charles H., Industrial Wastes and Salvage, Atlas Publishing Company, New York (1963). (5) Mills, Ross E., "Process Waste Burner Destroys Liquid Organic Chemical Wastes Safely," Water and Sewage Works, 111 (7), 337-340 (1964). (6) "Catalytic Oxidation System Clears Odors From Vinyl Processing Oven," Air Engineering, 8 (10), 20-21 (1966). # (7) Malten, K. E., and R. L. Zielhaus, Industrial Toxicology and Dermatology in the Production and Processing of Plastics, Elsevier Publishing Company, New York (1964). (8) Ungewitter, Claus, Science and Salvage, Crosby Lockwood & Son, Ltd., London, 110-111 (1944). (9) "Solid Waste Disposal Gets Federal Effort," Chem ical and Engineering News, 44 (51), 49-55 (1966). (10) "Solid Wastes," Environmental Science and Tech nology, 1 (3), 199-202 (1967) (11) Spilhaus, A., "Waste Management and Control," Committee on Pollution, National Academy of Sciences National Research Council, 1400, (1966). (12) "The Official Totals are In," Modem Plastics, 44 (2), 110-112 (1966) (13) Foster, William S., "Municipal Solid-Waste Dis posal-Nature and Magnitude," The American City, 77 (2), 105-107 (1962). (14) "The Plastics Industry in 1966: The Facts and the Figures," Modem Plastics, 44 (5), 115-122 (1967). 17 ASI 00000483 (15) "What's New in Plastics for Packaging?,'' Modem Plastics, 42 (10), 92-95, 156-157 (1965), (16) "Big Market for Blown PS Bottles?," Modem Plastics, 43 (8), 92-93, 199 (1966), (17) "Plastic Bottle Use to Rise 13 Percent," Chemical and Engineering News, 45 (1), 14 (1967) (18) "The Battle for Bottles," Modern Plastics, 41 (10), 99-103, 172 (1964). (19) "Plastics Bottles Summary for 1965," Current Industrial Reports, Bureau of the Census, Series M 30E (65)-5, August 17, 1966. (20) "Forecast for FVC Bottles: Clearing," Modem Plastics, 44 (4), 105-109 (1966). (21) "Glass: Fighting Back with New Strength," Mod em Packaging, 40 (5), 112-116 (1967). (22) "Packaging --A Market that accommodates both the Giant and the Little Guy is Poised for Phe nomenal Growth," Modem Plastics, 43 (10), 202204, 330, 335 (1966). (23) "The Outlook for Materials: Continued Growth, New Markets, Lower Prices --And Capacity Ex pansion," Modem Plastics, 43 (10), 133-140, 278 (1966). (24) "Progress is Reported on Refuse Disposal," Envi ronmental Technology and Economics, 1 (4), 8 (1965). (25) "FDA Approves Clear, 'Polyethylene -- Modified PVC Compound," Plastics World, 25 (1), 22-25 (1967). (26) Eberhardt, H., "European Practice in Refuse and Sewage Sludge Disposal by Incineration," Com bustion, 38 (4), 23-29 (1966). (27) Potter, B., "The Bottle Pack System," Plastics, 32 (351), 71-72 (1967). (28) Eberhardt, H., "European Practice in Refuse and Sewage Sludge Disposal by Incineration," Combus tion, 38 (3), 8-15 (1966). (29) Hanna, G. M., and Curley, L, C., "Rapid Cor rosion of Combustion Equipment from Hydrocar bon Vapors, Parts I and II," Air Conditioning, Heating and Refrigeration News (July 26, 1965, and August 2, 1965). (30) Air Pollution, Volume II, Edited by Arthur C. Stem, Academic Press, New York (1962), 476-478. (31) First, Melvin W., and others, "Control of Toxic and Explosive Hazards in Buildings Erected on Landfills," Public Health Reports, 81 (5), 419-428 (1966). (32) "Toxicity of Plastics," British Plastics, 31 (3), 115 (1958). (33) Chancellor, S. F., "Toxicity of Plastics," Nature, 185 (4716), 841 (1960). (34) Pound, Charles E., "Our Landfill Plays Favorites," The American City, 79 (1), 85-86 (1964). (35) Michaels, Abraham, "Municipal Solid Waste Dis posal--The Sanitary Landfill," The American City, 77 (3), 92-94 (1962). (36) Tietjen, Cord, "Conservation and Field Testing of Compost," Proceedings, National Conference on Solid Waste Research, December, 1963; American Public Works Association Special Report No. 29, 175-187 (1964). (37) Treatment and Disposal of Refuse and Sewage Sludge, 3rd International Congress, Trento, Italy, May 24-29, 1965, Associazione Nationale Di Ingegnerla Sanitario, Andis, Italy. (38) Wessel, C. J., "Biodeterioration of Plastics," Soci ety Plastics Engineers Transactions, 3 (4), 193207 (1964). (39) Weststrate, W. A. G., "Composting of City Refuse," Proceedings, National Conference on Solid Waste Research, December 1963, American Public Works Association Special Report No. 29, 136-149 (1964). (40) Schulze, K. L., "Composting as a Waste Disposal Method," Proceedings of a Short Course, Tech nical and Planning Aspects of Solid Wastes, spon sored by the Ohio Department of Health and the United States Public Health Service, Columbus Ohio, September 20-24, 1965, pp L1-L19. (41) "Garbage In, Merchandise Out," Scientific Amer ican, 216 (1), 58 (1967), (42) Riazanov, A. V., "Criteria and Methods for Estab lishing Maximum Permissible Concentrations of Air Pollution," Bulletin World Health Organiza tion, 32, 389-98 (1965). (43) Eliassen, Rolf, "Domestic and Municipal Sources of Air Pollution," Proceedings National Conference on Air Pollution, Sponsored by U. S. Public Health Service November 18-20, 1958, Published by Department of Health, Education and Welfare, Washington, D. C,, (1959), 132-139. (44) Proceedings, National Conference on Solid Wastes Research, December 1963, American Public Works Association Special Report No, 29 (1964), 37. (45) "How to Reduce Air Pollution," Engineering (July 1, 1966). 202 (5228), 8 (1966). (46) Meetham, A. R., Atmospheric Pollution, MacMillan Company, New York (1964). (47) Report of the Air Conservation Commission of the American Association for the Advancement of Sci ence, AAAS Publication, No. 80, Washington, D. C. (1965). (48) Dickinson, Janet E., "Technical Progress ReportAir Quality of Los Angeles County," Los Angeles Air Pollution Control District, 2, Los Angeles (1961). (49) Magill, Paul L. and others, Air Pollution Hand book, McGraw-Hill, New York (1956). (50) Riasanov, A. V,, "New Data on Maximum Allow able Concentration of Pollutants in the Air in the U.S.S.R.," Proceedings of the Diamond Jubilee Intematiorthl Clean Air Conference, October 20-23, 1959, National Society for Clean Air, London, 175-176 (1960). ASI 00000484 (51) Blomquist, E. T., "Federal Activity in Developing Air Quality Criteria," Journal of the Air Pollution Control Association, 16 (10) 530-531 (1966). (52) Tebbens, Bernard D. and others, "Particulate Air Pollutants Resulting from Combustion," Sym posium of Air-Pollution Measurement Methods, (ASTM Special Technical Publication No, 352, American Society for Testing and Materials, Phila delphia (1963), 3-31. (53) Griswold, S. Smith, Technical Progress Report-- Control of Stationary Sources, Volume 1, Air Pollution Control District, County of Los Angeles, Los Angeles (1960). (54) Goss, W. F, M., "Smoke Abatement and Electrifi cation of Railway Terminals in Chicago," Report of the Chicago Association of Commerce Com mittee of Investigation on Smoke Abatement and Electrification of Railway Terminals, Rand Mc Nally and Company, Chicago (1915). (55) Thomas, C. H, and Coleman, E. H., "The Prod ucts of Combustion of Chlorinated Plastics," Jour nal of Applied Chemistry, 4, 379-83 (1954). (56) Scheiner, Lowell L., "How to Handle Scrap and Regrind," Plastics Technology, 11 (8), 37-47 (1965). (57) Markus, Thomas A.. "Soil Stabilization by Syn thetic Resins," Modern Plastics, 33 (2), 152-158 (1955). (58) Brown, Clement. "Waste Recovery Pays --Even in Prosperity." Engineering. 190, 539 (1960). (59) Mandell. Leonard C. "Refuse Disposal in Rhode Island 1965-1990." Rhode Island Development Council (August 1965). (60) "Strong Federal Control Over Air Pollution Asked by Johnson. Fight Looms m Congress," Wall Street Journal, (Midwest Edition), 47 (75), 2 (1967) (61) "Municipal Refuse Collection and Disposal," Dept, of Health, State of X. Y. (1965). (62) Gordon, Mitchell, "More Federal Power, Regional Control Likely in Anti-Pollution Drive," The Wall Street Journal (Midwest Edition), 47 (70), 1 (1907). (63) Fenimore, C. P. and Martin, F. J., "Flammability of Polymers," Combustion and Flame. 10 (2), 135-139 (1966). (64) Penski, E. and Goldfarb, I., "Mechanism of Ther mal Degradation of Polymers," Air Force Con ference on Elastomer Research and Development, October 22-24, 1962, Volume 2, Office of Naval Research, Publication ONR-13, 2, Washington, D. C. (1962). (65) Schriesheim, A., "Method for the Controlled Burn ing of Combustible Materials and Analyses of the Combustion Gases," Fire Research Abstracts and Reviews, 2 (1), 160-161 (1960). (66) Cass, R. A., "Smoke Control Design," Journal of Cellular Plastics, 3 (1), 41-43, (1967). (67) Coleman, E, H., "Gaseous Combustion Products from Plastics," Plastics, 24 (264), 416-417, (1959). (68) Madorsky, S. L. and Straus, S., "Thermal Degra dation of Polymers at High Temperatures," Fire Research Abstracts and Reviews, 2 (1), 115-116, (1960). 19 ASI 00000485 APPENDIX A Present Consumption and Future Usage of Plastic Bottles Of all major containers and materials in the packaging industry, plastic bottles have experienced one of the fastest growth rates during the past 6 years, tripling in unit volume since 1960. This appendix summarizes the results of a limited effort to forecast the future outlook for plastic-bottle usage. PRESENT CONSUMPTION Table A-l shows a breakdown of plastic-bottle shipments (and captive production) for important end-use applications. Household chemicals, primarily bleach and liquid deter gents, presently represent the largest end-use application. Battelle estimates that in 1966 resin usage for plastics bottles was approximately as follows: High-density polyethylene--270 million pounds Low-density polyethylene --20 million pounds Polyvinyl chloride--10 million pounds Polystyrene and other --5 million pounds. It should be noted, of course, that the total of plastic bottles shown in Table A-l does not necessarily equal plastic-bottle delivery to municipal refuse systems. The need for three adjustments should be considered to reflect the following: (1) Consumption of bottles does not necessarily equal production. (2) Some bottles undoubtedly find semipermanent use around the home and else where and do not enter disposal systems. (3) A certain percentage of plastic bottles, like other consumer packages, are dis posed of in rural areas or in other locales not possessing municipal refuse systems. FUTURE OUTLOOK Industry spokesmen and market-research personnel agree that there will be a minimum of 10 percent annual growth in both the number of plastic bottles used and the weight of plastic resins consumed in bottle production during the next 5 to 10 years. The extent to which growth may exceed this minimum projection depends largely on the success which plastic bottles experience in penetrating several large potential markets. The largest of these markets is milk packaging. Rough forecasts have been made at two levels above the minimum annual growth rate of 10 percent. The "high" estimates discussed in the following pages assume highly favorable circumstances that should result in a broad acceptance and usage of plastic 20 ASI 00000486 bottles. The "best" estimates correspond to the circumstances judged most likely to occur during the next 10 years and represent probable usages of plastic containers for the various markets. Table A-2 summarizes Battelle's "best" and "high" estimates for unit usage of plastic bottles. These unit estimates, of course, were used in making the resin-consumption esti mates shown in Table A-3. The "low" estimates for plastic bottles shown in the body of the report were based on the assumption of the 10 percent growth rate mentioned above. Assumptions Made in Forecasting Assumptions that were made to arrive at the "best" and "high" estimates for various markets are discussed below. Household Chemicals. The bleach and liquid-detergent markets are assumed to be saturated by plastic bottles. For the "best" estimate, these two markets are forecast to grow at a 4 percent annual rate on a weight basis and at a slightly lower rate on a unit-volume basis because of a continuing trend to larger container sizes. The householdchemicals market for plastic bottles is expected to experience additional growth because of greater use of plastics for dry cleansers and other household-chemical products. The "high" estimate for household chemicals assumes a growth rate of 6 percent annually for bleaches and liquid detergents. This estimate also assumes that the dry cleanser and other household categories will grow at double the rate assumed in making the "best" estimate. Most of the growth in household chemicals will involve polyethylene bottles, although polyvinyl chloride is expected to experience a significant increase in some household chemical applications. Toiletries and Cosmetics. Battelle's "best" estimate for this market segment assumes a 20 percent annual growth in bottle use through 1971 and a 15 percent annual growth from 1971 to 1976. The high estimate assumes a 30 percent annual growth rate during the next 5 years, and 20 percent thereafter. Polyvinyl chloride bottles are expected to become increasingly important in this market sector. Medicinal and Health. This market segment is expected to grow substantially as plastic bottles replace glass in many applications. Both polyvinyl chloride and high-impact polystyrene should have significant positions in this market. Milk Packaging. In 1966, about 70 million disposable plastic milk bottles were pro duced requiring about 15 million pounds of high-density polyethylene resin. Penetration of plastic bottles into the total milk-packaging market has been relatively small. Total production of new milk containers includes over 1.0 billion 1-gallon containers, about 9.0 billion half-gallon containers annually. Battelle's "best" estimate is that plastic bottles will achieve a 20 percent penetration of the market for milk in 1-gallon and half-gallon containers by 1971 and a 50 percent penetration by 1976. It was assumed that, on an economic basis, gallon and half-gallon containers will be most susceptible to plastic penetration. It was also assumed that return able plastic bottles --now being used primarily in the Pacific Northwest--will not become a significant factor in the market. 21 ASI 00000487 TABLE A. 1. MAUFACTURERS' SHIPMENTS AND CAPTIVE PRODUCTION OF BLOW-MOLDED PLASTIC BOTTLES BY END USE End Use Quantity of Bottles, millions of units 1965 1966 Household chemicals.................... ....... Bleach........................................... ........ Detergent, liquid................................ All other.............................................. Toiletries and cosmetics.............. ....... Medicinal and health................... ....... Food and beverage...................... ........ Milk............................................... ....... All other............................................. All other * Total................................................. ....... 1,658 513 813 332 579 265 91 34 56 130 2,723 1.739 504 802 434 769 288 139 74 64 176 3,111 Percent of Total Units in 1966 56 25 9 6 100 Source; Current Industrial Reports Series M30E(66)--10, "Plastic Bottles," V S. Dept, of Commerce. TABLE A-2. FORECAST DATA ON PLASTIC BOTTLES End Use Household chemicals................. Toiletries and cosmetics........... Medicinal and health................ Food and Beverage: Milk....................................... All other food and beverage..................... Motor Oil.................................. All other..................................... Total........................................... "Best" Estimate, millions of bottles 1971 1976 2,300 1,930 800 2,800 3,900 1,200 2,200 5,600 500 1,200 800 1,500 200 400 16.600 High Estimate, millions of bottles 1971 1976 2,900 2,850 1,400 3,700 7,000 2,000 6,600 9,000 2,000 1,500 300 17.550 4,000 2,000 900 28.600 Source: Battelle estimates. For the "high" estimate, plastic bottles are assumed to capture 60 percent of the milk packaging market by 1971, and 80 percent by 1976. All Other Food, and Beverages. Plastic bottles have been widely publicized as food and beverage containers in recent years. Some products, including syrups, mustard, ketchup, sweeteners, cooking oils, and salad dressings, are now being commercially packaged in plastic bottles. However, this market has not provided the tremendous growth prospects to date that many feel it should. Two obstacles to revolutionary changes in this market are the inadequacy of poly ethylene and polystyrene for packaging many sensitive food products, and the lack of FDA regulation for polyvinyl chloride with required stability. The "best estimate" for this category assumes that these obstacles will be circumvented. In the maximum estimate, it is assumed that in addition new economies in plastic-bottle production will be achieved. 22 ASI 00000488 The two largest single container markets are for soft drinks and beer. These beverages require the use of about 50 billion and 40 billion containers respectively per year, although a major portion of soft drinks are filled in multitrip returnable bottles. Because of the severe technical constraints (pressure and barrier requirements), plastics are not expected to obtain a share of this market in the next 10 years. However, The Society of the Plastics Industry should note the size of this market for long-term planning purposes. Motor Oil. The packaging of motor, oil in plastic cans has received considerable attention in recent years. The 1-quart oil-can market is estimated currently at a 2-billion unit per year market. Battelle's "best estimate" assumes a 40 percent penetration of this market in 1971, and a 75 percent penetration in 1976. The maximum penetration is estimated at 75 percent in 1971 and 100 percent in 1976. All Other Applications. Other applications for plastic bottles and cans include the packaging of industrial chemicals, paints and varnish, automotive fluids of various sorts, and other miscellaneous products. These and other markets should grow substantially in the next 10 years. Annual growth rates of 15 and 25 percent are assumed under the "best" and "maximum" estimates respectively. Plastic Bottles by Type of Plastic Resin Consumptions of important types of plastic resins corresponding to the "best" and "high" estimates for quantities of bottles shown in Table A-2 are forecast in Table A-3. TABLE A-3. PLASTIC BOTTLES ACCORDING TO TYPE OF RESIN (Millions of Pounds) 1966 Polyethylene, LD& HD........................ Polyvinyl chloride............................... Other resins.......................................... Total...................................................... 290 10 5 305 1971 Best High 700 1300 120 240 80 360 900 1900 1976 Best High 1200 250 350 1800 2000 350 650 3000 Source: Battelle estimates. APPENDIX B Role of Plastics on a Weight Basis Before estimates can be attempted on future plastics percentages in municipal wastes, a base-line of the current situation must be established. Although many references are available on plastic production!1112) and much has been written on overall solid-waste disposal problems,!9101314) there is almost a complete lack of information linking plastics 23 ASI 00000489 TABLE B-l. COMPOSITION AND ANALYSIS OF AN AVERAGE MUNICIPAL REFUSE Determined From Samples Taken 1959-62 Percent of Total Refuse Proximate Analysis!*1 "As Received" Basis, weight percent Moisture Volatile Matter Fixed Carbon Noncombustible*(k) Btu per lb Dry, Dry Ash-Free Basis Basis Rubbish, 647t> Paper, mixed Wood and bark Grass Brush Greens Leaves, ripe Leather Rubber Plastics Oils, paints Linoleum Rags Sweepings, Street Dirt, Household Unclassified 42.0 2.4 4.0 1.5 1.5 5.0 0.3 0.6 0.7 0.8 0.1 0. 6 3.0 1.0 0.5 10.24 20.00 65. 00 40.00 62.00 50.00 10.00 1.20 2.00 0.00 2.10 10.00 20.00 3.20 4.00 75.94 67.89 -- -26. 74 -68.46 83.98 -64. 50 84. 34 54.00 20.54 -- 8.44 11.31 -- -6.32 -12.44 4.94 -- -- 6.60 3.46 6.00 6.26 -- 5.38 0.80 2.37 5. 00 4.94 4. 10 9.10 9.88 10. 00 16.30 26.80 2.20 20.00 70.00 60. 00 7572 8613 7693 7900 7077 7069 8850 11330 14368 13400 8310 7652 6000 3790 3000 8055 8700 8250 8600 8135 7700 9850 12600 16000 16000 11450 7844 8000 13650 8000 Food Wastes, 12% Garbage Fats Noncombustibles, 24% Metallics Glass and ceramics Ashes 10.0 2.0 8.0 8.0 6.0 10.0 100.0 72.00 0.00 3.00 3.00 2.00 10.00 20.26 -- 0.5 0.5 0.4 2.68 3.26 0.5 0.5 0.4 24.12 4.48 0 96.0 96.0 97.2 63.2 8484 16700 124 124 65 4172 10100 16700 12000 12000 8000 14000 (a) Baaed on ASTM methods of analysis of coal and coke, as adapted for refuse. (b) Noncombustibles - ash, metal, glass and ceramics. Source: Reference (44). to solid waste. One reference^15) was found giving a detailed analysis of average muni cipal refuse from several United States cities. As shown in Table B-l, this breakdown includes plastics at 0.7 percent of the total refuse analyzed based on 1957-1962 data. If this percentage still holds, plastics in municipal waste today would amount to 250 (0.007) = 1.75 billion pounds. Because of the increased use of plastics during the last 5-8 years, this number is probably low. One method of determining this present base line is to use overall plastics-production figures^11) and assume that the proportion of material going into waste remains un changed. Overall plastic production has increased by about 210 percent during the last 6 years while solid-waste production!10) has increased only 120 percent. If it is assumed that the fraction of total plastics production going to municipal waste remains unchanged, the current (end of 1966) percentage of plastics in solid waste would increase to /210\ (0'7)l 120 ) = 1-14 percent, 24 ASI 00000490 and the total weight of plastics in solid waste today would be 0.0114(250) = 2.9 billion pounds. A second method to determine current numbers would be to utilize the percentage increase in packaging materials (Table 1), since packaging wastes may be the largest single source of plastics in municipal refuse. Packaging-materials production has increased 240 percent in the last 6 years. Applying this to the 1959-62 plastics-in-solid waste percentage would yield a current percentage of 0.7 1.4 percent and the current weight of plastic waste of 3.5 billion pounds. A third way to provide this estimate was attempted using current plastics production figures(11) and current solid-waste figures^10! only. In this case the production breakdown in Reference (11) was analyzed and estimates of current production earmarked for short term consumer use were made. The results of this extremely quantitative approach is shown in Table B-2. As shown in Table B-2, the total estimated weight of plastic in municipal waste is 3.9 billion pounds or about 1.6 percent of the total 1966 municipal refuse generated in this country. Since it is anticipated that plastic containers and other packaging materials may be the largest single plastics source, and since the data in Table 3 closely compares with estimates based on packaging-production changes, Battelle's "best estimate" for current values of plastic wastes in municipal refuse is 1.5 percent of the total or 3.75 billion pounds. The results of the analysis of production figures cited above also provides an estimate of the possible current composition breakdown in the plastic portion of municipal refuse. As indicated by Table B-2 plastics in municipal refuse consist primarily of polyethylene (38 percent), polyvinyl chloride (31 percent), and polystyrene (21 percent). TABLE B-2. ESTIMATE OF TOTAL PLASTICS IN MUNICIPAL REFUSE - 1966 Plastic Material __________ Amount, millions of poundi Nylon Phenolic* Polyacetals Polycarbonate Polyethylene Polypropylene Polyvinyl chloride Polyester* Polystyrenes Urea and melamine Urethane foam Cellulosics Total 7.9 22.5 3.5 3.4 1446 71 1204 51 823 79 89 60 3860 Percent of Total 0.2 0.6 0.1 0.1 37.6 1.8 31.2 1.3 21.3 2.0 2.3 1.5 100.0 Reference 25 ASI 00000491 APPENDIX C Government Activity in Solid Waste09,59,6'61'62) The Federal, State, and local Governments have been increasing their influence on procedures for refuse disposal. The Solid Waste Disposal Act, Public Law 89-272 passed by Congress on October 20, 1965, states: .. that while the collection and disposal of solid wastes should continue to be primarily the function of State, regional, and local agencies, the problems of waste disposal have become a matter national in scope and in concern and necessitate Federal action through financial and technical assistance and leadership in the development, demonstration, and application of new and improved methods and processes to reduce the amount of waste and unsalvageable materials and to provide for proper and economical solid-waste disposal practices___" The Federal Government is concerned with protecting the health and welfare of the people-against the .. inefficient and improper methods of disposal of solid waste (that) result in scenic blights, create serious hazards to the public health, including pollution of air and water resources, accident hazards, and increase in rodent and insect vectors of disease, have an adverse effect on land values, create public nuisances, otherwise interfere with community life and development___" In addition there is concern that the failure or inability to salvage and reuse such materials economically results in the unnecessary waste and depletion of our natural resources. "The purposes of this Act therefore are -- (1) to initiate and accelerate a national research and development program for new and improved methods of proper and economic solid-waste disposal, including studies directed toward the conservation of natural resources by reducing the amount of waste and unsalvageable materials and by recovery and utilization of potential resources in solid wastes; and (2) to provide technical and financial assistance to State and local governments and interstate agencies in the planning, development, and conduct of solid-waste disposal programs." The role of the Federal Government is, then, to sponsor research and development in this area and provide technical and financial assistance for refuse-disposal programs. The role of the State Governments at the present time is to gather basic data and to provide technical and economic assistance to municipal officers. Most legislation is at the local level, but several States have general prohibitions against the disposal of solid wastes along highways, on specific land, or into the waters of the State. Two States, California and New Jersey, have outlawed open dumping. Several States limit storage of refuse in buildings. Most States have regulations concerning air and water pollution that indirectly control solid-waste disposal. Specific violations of State regulations may 26 As* 00000492 arise from the disposal of solid-waste material into the waters of the State or from air pollution caused by backyard burning, burning at an open dump, an improperly oper ated incinerator, or stench from an open dump. Because of the wide effects of air and water pollution, States and in some cases the Federal Government rather than local areas have become the controlling agencies. Most states have legislation that enables municipalities to make their own laws. The responsibility for refuse collection and disposal almost invariably rests on municipal officials. Municipalities have generally found it advisable to enact codes or ordinances regulating refuse disposal. These regulations customarily are designed to control back yard burning, use of home incinerators, use of garbage grinders, private disposal prac tices, and temporary storage of refuse by householders and commercial establishments. There has been limited activity by all levels of Government, particularly State and Federal, until recently. One of the major keys to expansion of activity in this area is Public Law 89-272. The law created the Office of Solid Wastes in HEW and divided responsibility for development of technology between it and the Bureau of Mines in the Department of the Interior. The current budget of the Office of Solid Wastes is $12.5 million. The Bureau of Mines is responsible for dealing with metallurgical and fossil fuel wastes under a $4.3 million fiscal 1967 grant and a contract program. Current activity is limited to gathering data and studying the problem. The next step will be to formulate policies, programs, and perhaps laws. State and Federal statutes are not likely to control solid-waste disposal systems but are more apt to simply facilitate such control at the local level. APPENDIX D Fire Hazards Peculiar to the Use of Plastics Materials such as wood, rubber, chlorinated methylacrylate, wool, silk, and other fabrics when thermally decomposed generate a variety of toxic gases such as ammonia, carbon dioxide, carbon monoxide, hydrogen chloride, hydrogen cyanide, hydrogen sulfide, sulfur dioxide, phosgene, and oxides of nitrogen. Smoke, although generally not considered to be toxic in the sense of the above gases, is a primary life hazard due to its effect on visibility and its irritating effect on the nose and eyes. A large number of full-scale burning tests were conducted, and, in most, the hallways became intolerable because of smoke prior to the development of excessive heat; of course, these results depend upon the location of the sampled area relative to the fire zone. The flammability of polymers has been measured by Fenmore and Martin^63^ and the mechanism of thermal degradation of polymers has been described by Penski and Goldfarb(64i and Schriesheim.(65i R. A. Cass(66> has reported on a method of quantitatively measuring the potential amount of smoke produced by a given fire and a method of measuring the light trans- 27 ASI 00000493 TABLE D-l. WEIGHT PERCENT SMOKE FROM VARIOUS PLASTIC PRODUCTS Material Wood, Red Oak Polymethyl Methacrylate Self-Extinguishing PMMA 1. Containing?. Br, and Cl 2. Containing P. Br, and Cl 3. Containing?, Br, and Cl General Purpose Polyester Self-Extinguishing Polyesters 1. Containing?, Bt, and Cl 2. Containing P and Cl 3. Containing P and Cl 4. Containing P and Br * Self-Extinguishing Laminate 1. Containing glass fiber, filler, and probably Sb2C>3 2. Containing glass fiber, Halogen, P 3. Containing glass fiber, Halogen, P 4. Containing glass fiber, Halogen, P 5. Containing glass fibers, Halogen, P,and 5^03 6. Containing glass fibers. Halogen, P.and Sb203 7. Containing glass fibers. Halogen, P,and SIJ2O3 Urethane Foam Self-Extinguishing Urethane Foam 1. Containing P 2. Containing P and Cl Polyvinyl Chloride Vinyl Covered Fabric X 2 3 Percent Smoke 0.20, 1.10, 0.37, 0.27 3.9, 2.8 9.0, 9.2 10.4, 9.8 13.4, 12.2 16.7, 17.2 15.7, 15.6 17.8, 19.2, 16.8, 18.3. 20.0 11.1, 11.0, 12.4, 11.7 17.2, 18.1, 18.4, 15.6, 17.9, 16.6 4.6 11.1, 10.6 11.9, 12.0 7.3, 7.8 7.2, 8.0 12.0, 12.6 11.4, 12.0 9.3, 9.7 11.5, 10.0, 10.6 7.7, 9.2 8 8.5. 7.6, 7.4 4.9, 5.5, 4.6 6.5, 6.6, 6.8 mission of that smoke. Using this information he evaluates the degree of visibility under such conditions. His measurements of the weight percent of smoke from various plastic products are shown'in Table D-l. Mr. Cass determined the amount of light absorbed by these smokes. The Amounts of burning materials that will produce total light extinction in a (12x 15x8 feet) 1440 cu ft room were calculated from these data to be: Material Pounds Completely Burned Red oak...................................................... 390 PMMA......................................................... 390 PMMA, self extinguishing..................... 7.75 FVC............................................................... 7.6 Polyester, flame resistant........................ 7.7 28 00000494 ASI TABLE D-2. SUMMARY OF DECOMPOSITION PRODUCTS OF PLASTICS Mate rial Melamine reain paper, or wool Wood Method of Testing Oxygen, 2 Heated in a current of air and products passed over rats in cage* 5 Lb burned in 1 10 ft3 ii r 9. a Carbon Dioxide, co2 62 Carbon Monoxide, CO Chlorine, Cl2 Analym, percent volume Hydrogen Ca rbonyl Chloride, Chloride, HCl coci2 Hydrogen Cyanide, HCN Ammonia. NHj Hydrogen Sulphide, h2s Not analysed 6 2 .. Rubber Insulation on cable in 5- 1 flask 6 6-15.4 6 6-13.6 Wool Silk Heated in ailica tube with a current of air 6 6- 14.1 4. 6-9.2 4 0-6.0 6. 0-12.6 Timber and fibre insulating board Burning house 19. 9 1. 6 0. 7 17. 8 5.4-7. 6 0.5-5.0 3.0-4.4 0. 3 19.8 --- - .. _. -- 1 3-2 5 1 3-2.6 -- 2 .2-6. 8 3 1-3 6 ... _ _ --- 0] 0. 020.40 -__ - 0. 5 9. 2 16. 7 -- -- -- -- -- Chlorinated metkracrylate resin 27% chlorine Polyvinyl chloride 57% chlorine Polyvinyl chloride fabric 0. 5 g at 550 C in $ 1 air 0, 25 g at 550 C In 5 1 air 0. 5 g at 550 C in 5 1 air Plywood Heated at 550 C in 5 1 air Plywood PVC and flame - reta rdant paint Heated at 550 C In 5 1 air Plywood with polyeater reain and flame -retardant paint Heated at 550 C in 5 1 air PVC coating only Heated at 550 C in 5 1 air Vinyltdeae coating only Heated at 550 C In 5 1 air Poamed poly vinyl chloride Foamed acrylonitrile 2-5 g heated electrically in 270 1 air Phenolic reain with filler* Melamine reain with fillere Aa above n. d. n d. n. d. 2. 8 2. 1 2. 6 2.6 2. 1 2. 0 17. ] 17. 1 14.7 2. 2 1. t 0.4 3.6 5. 1 13. 2 0. J 17.0 10. 1 0.4 5.6 20.7 0.16-0.35 0.023-0. 040 19.3 1.26-1.31 0. 041 n. d. n.d. n.d. n.d. 0.017-0. 046 0.012-0. 075 0.0 0. 0 n. d. ... 00 0.0 -- 0.6 18 2.9 -3. 1 3. 8 4.7 1. 1 0.0050.023 0.002 -- 0.0005 0.0005 n. d. __ __ __ ,, __ ._ __ ... __ 0. 0 0.0 -- ... _ _ 0.0OE0.003 0.002 0.0020.003 0. 002 0-0 003 0.0020 25 0.0020. 110 0.0060. 180 .. .... .. -__ .... Nitrous Fumes ss NOa -- .. -- __ .. 0.0010.002 0. 002 __ N otei Demonstration that iho1 toxicity was due to ca: bon monoxide and not hydrogen cyanide 10% of hydrocarbons 3 min from start ].9%hydrogen 12 mm from start. 47% hydrogen IB ming from start. 3 4% hydrocarbons Testa made to examine effects of blowing agent*. Carbon monoxide was and cotton. ASI 00000495 ASI 00000496 coo TABLE D-3. THE PHYSIOLOGICAL EFFECTS OF SOME GASES WHICH MAY OCCUR IN FIRES Effect Carbon Monoxide, CO Chlorine, Cl2 Hydrogen Chloride, HC1 Concentration, parts per million Carbonyl Hydrogen Hydrogen Chloride, Fluoride, Cyanide. COCl2 HF HCN Ammonia, NH2 Safe for several hours 100 0.35-1.0 10 Safe for 1 hour 400-500 4 50-100 Dangerous 1/2 to 1 hour 1500-2000 40-60 1000-2000 Fatal in 1/2 hour 4000 -- -- Rapidly fatal Least amount causing throat irritation --- 1000 15 1300-2000 35 Least detectable odor 3.5 -- (a) Sense of smell lost after 2 to 15 minutes exposute to 100-150 ppm. 1.0 -25 -- 50 3.1 5.6 1,5-3.0 20 100 10 50-60 100 50-250 100-240 2500-4500 -- 200-450 -- -- 3000 5000-10, 000 -- -- 408 -- -- 53 Hydrogen Sulfide, h2s Nitrous Fumes as NOu 20 10-40 -- -- 200 100-150 600 -1000 200-100 100 62 lt/al PVC produces the most dense smoke. It is 1.4 times as dense as self-extinguishing PMMA, 1.7 times as dense as flame-resistant polyester, 19 times as dense as PMMA, and 6 times as dense as red oak smoke. Gaseous Products. The hazards resulting from gaseous products of combustion of plastics have been reviewed by Coleman.!67) A summary of decomposition products is shown in Table D-2. The physiological effects of some gases which may occur in fires is shown in Table D-3. The principal gases formed are CO2 and CO. The chlorine in chlorinated plastics is converted to HC1 with only a trace of phosgene. Phenolic and melamine resins produce hydrogen cyanide and ammonia but only in small, tolerable amounts. Silk and wool, on the other hand, produce quantities of HCN and NH3 in the rapidly fatal concentration range. Pyrolysis of rubber produces quantities of H2S and SO2 that are also in the rapidly fatal range. The major toxic hazards that all burning materials have in common are oxygen deprivation and generation of CO. Coleman states, "In the early stages of a fire located in a confined area the com bustion process is essentially complete generating little carbon monoxide; however, as the oxygen is depleted the combustion process becomes more incomplete and the carbon monoxide concentration rises rapidly. Where ample oxygen is present a further problem arises since the air temperature within a burning structure may quickly exceed the thermal ignition temperatures of many of the combustible product gases, thereby generating the additional hazard of a gaseous explosion." Experimental studies have been made to establish what determines the kind and amount of degradation products produced by burning plastics.!67) It was found that tertiary or quaternary carbon atoms in the chain weaken adjacent C-C bonds so that scission occurs primarily in the backbone of the chain. These poly mers vaporize completely at high temperatures. The decomposition products of poly styrene at 850 C in vacuum are CO, benzene, styrene, and a mixture of dimers, trimers, and tetramers. Since this is a spectrum of materials the final mixture depends upon where the spectrum is cut. Abundant hydrogen on the chain results in random scission. Volatile products vary from a single carbon atom to the largest fragments volatile at the pyrolysis temperature. There is a partially carbonized residue; not all the material volatilizes. Polyvinylidene fluoride did not volatilize beyond 87 percent when heated rapidly at 800 C. The principal decomposition products were H2, CO, and HF. Polyacrylonitrile did not volatilize beyond 94 percent. Decomposition products were chiefly H2. HCN, acrylonitrile, and vinylacrylonitrile. Scarcity of hydrogen leads to monomer formed by unzipping chain ends and ends produced in random scission. The residue formed is a carbonized honeycombed structure. Polytrivinylbenzene stabilized at 68 percent volatilization when heated rapidly. Products were mainly hydrogen and hydrocarbons from CH4 to CnHie. There was significantly more methane and ethylene the higher the temperature. It was concluded the molecular structure of the polymer determines its stability, the mechanism of degradation, and the amount and chemical nature of the products. 3) ASI 0000049? j 4 THE SOCIETY OF THE PLASTICS INDUSTRY, INC. 250 Park Avenue, New York, New York 10017 ASI 00000498