Document B8MregoezmL76jmw3bQ67KYdk

FILE NAME: Asbestos Sacks and Bags (ASB) DATE: 1980 DOC#: ASB016 DOCUMENT DESCRIPTION: Canadian Journal Article - Packaging Asbestos & Asbestos Substitutes More Expensive PUBLISHED BY L'ASSOCIATION DES MINES D'AMIANTE DU QUBEC mMm JUL./AUG./SEPT. 1980 VOL. 4/NO 4 Substitutes: higher cost, lesser quality "If asbestos were banned in roof cements, the market would be flooded with products so inferior in quality that they cannot perform the purpose for which they are intended." Such is the opinion expressed by an American expert at a symposium of national scope held in the United States on the whole question of substitutes for asbestos (National W orkshops on S u b s titu te s fo r Asbestos). Mr. Eric W orm ser, of G ibsonHomans, the largest U.S. manufacturer of sealing and coating compounds, was Invited fcTrevTCw- the numerous problems posed by the replacement of asbestos in various products. His analysis was based on the results of several studies and tests conducted by his company in an attempt to find and develop valid substitutes for asbestos. A According to Mr. Wormser, all the 'money and efforts invested in the search for substitutes have yet to give satisfactory results, particularly in the case of sealing and coating compounds foTTSofs. In these products, fhe~~as~best<5s~fibre acts as a binding agent and helps to increase the cohe sion, viscosity, elasticity and plasticity of the mixtures. Being inert, it is not subject to aging, and so enhances the resistance and the durability of the products. Conclusive experiments In spite of the tremendous amount of work that has been done to try to find a substitute raw material that will produce satisfactory roof coatings and roof cements, to the best of our knowledge no one has found such a material. As the result of our com pany's vast research, by complicated formulating techniques, utilizing a variety of ingredients and techniques, we are now able to produce solvent base asphalt roof coatings and roof cem ents which do not Include asbestos fibre. We do not yet offer\ (these asbestos free roof coatings and' cements for sale in the United States because they are about 15% more \ expensive to produce and we believe 'they are not as good as comparable, products made with asbestos. It is difficult to justify selling an inferior product for more money." j "We are shipping considerable quantities of asbestos free coatings and cements to Sweden, where the use of asbestos fibreln such products has been banned. Therefore, we are gain ing experience in the volume manufac tu re of such products and have the ^opportunity to observe their perfor mance in large scale use." Furthermore, Mr. Wormser feels that a ban on the use of asbestos in the manufacture of roof coatings and cements would be a great disservice to the public. " Once the asbestos is bound in the roof coating and cement vehicles, it can dd~rw harm to anvoneT Therefore, a barTwoUld not benefit anyone. On the other hand, it would force on the public a flood of very poor pro ducts at high prices." Energy savings While admitting that it is possible to produce asbestos free products, Mr. Wormser further pointed out that such production goes against the current trends in industry and government policies regarding energy consump tion. "The only method we know for manufacturing reasonably satisfactory asbestos free roof coatings and roof cements is to combine some less than satisfactory substitute fibres with a variety of mineral fillers, wetting agents, plasticizers and synthetic thix otropes." ` ` We m a n u f a c t u r e a b o u t 2 5 0 \ different roof coatings, cements and mastics. A variety of techniques must be used to achieve acceptable results , in each of these products. The end result in every case is a product that' contains considerably less asphalt, tar or other waterproofing oil and much more filler mat er i al than when asbestos is used. These fillers con tribute nothing to the waterproofing properties or weathering of the pro ducts. To the contrary, these filler materials often detract from the desira ble properties. These formulas require from 30 to 70% more energy in our plants to manufacture." A Health Finally, bringing up the subject of health problems which are said to be -- - -- BUrniRfflEi Packaging asbestos: ; 27 milion bags, 500 000 cu m. What a long way we have come from the early part of the century when the men had to use their Ingenuity to think up better, faster and easier ways of fill ing sacks with fibre. Nowadays, tech nicians monitor dials and signal lights as the bags of fibre roll by on con veyors. them open, and according to the few who remember, more than one was split and mended before one got " the knack" ! emptied, weighed and conveyed by machines, man's role being confined to stacking and loading. The discovery of pressure packing It is d oubtless because they dreamed of advanced automation that the workers in the mills were also inventors. We owe to their experience and creative minds, along with con siderable investments, many of the machines and techniques which have made it possible to improve working and environmental conditions. Burlap, needle and thread There was a time when asbestos fibre was not bagged but " sacked" . The burlap sacks were made in Quebec with imported jute, mostly from India. The problem of recycling the asbestos sacks was non-existent back then since they were used over and over, as long as they could still be mended. Mending was moreover an important activity which kept several dozen people busy at the mill. Mending was also part of the day-to- day work of the men who filled and handled the sacks; they always had needle and thread on them so they could immediately repair any ripped or Around 1935, the operation was was a turning point for the asbestos split sacks, in short the result of some modernized: the sack was now held industry, to such an extend in fact that miscalculated move. open on a cylindrical rack rather than research is still being done to improve by the worker and the knee which this technique and derive the greatest i Before the advent of pressure pack packed the fibre was replaced by a benefit from it. ing, the fibre used to be shovelled into piston. 1| sacks and packed down with a few In addition to solving part of the dust good thrusts of the knee. A major improvement: pressure problems, pressure packing has made I With a little experience, a " hand packing handling easier, reduced the amount of storage and transportation space sewed" sack could be filled, packed P re ssure p a c k in g , w h ich was required and, in so doing, cut down the and closed in three minutes. The full developed by Johns-Manville in 1950, cost inherent in these operations. sacks were sent up to the warehouse was adopted by the other mills a few f roof where they were tossed down years later and marked the beginning through a trap to the floor 25 feet of automation which from then on was rom burlap to paper below. Not everyone was handy at very rapid. Although still packaged in tossing the sacks without splitting burlap, the fibre was soon being A world burlap shortage in 1970, ombined with a growing preoccupa- i 4 4 ; . of wood, 435 tons of nails tion with health and environmental problems, brought into question the use of burlap sacks which did not offer a sufficiently hermetic wrapping, soluble wrapping -- paper, ink and glue -- which could be incorporated into the mixtures used in the manufac turing of finished products. K In 1973, an engineer at Asbestos C o rp o ra tio n ' s N orm andie Mine designed a machine which could which is available in 40 different models, represents an additional cost of $4 to $14 for every two tons of fibre, depending whether he orders a reusa ble pallet for shipping his own finished product or a disposable model. North American customers may even rent pallets, under an agreement with the rail companies which allows them to send back free of charge one wagon load of pallets for each order to five wagons of fibre. Today, of the seven million pallets manufactured in Qubec annually, around 600 000 are used by the asbestos producers. The manufactur ing involves 500 000 cubic metres of wood, 435 tonnes of nails and creates, at the regional level, about a hundred jobs. Metric conversion The container, the lift truck, the pa lle t, a ll are ele m ents co n trib u tin g to the safe tra nspo rtatio n o f asbestos fibre. automatically position the bags to receive the fibre and shortly after wards, all the companies adopted this technique. That same year, all the Since the bagging of fibre began, the industry has used 100 and 125 pound burlap sacks, then 100 pound paper or plastic bags, such standardization making it easier for the manufacturers to develop their mixtures. machines in the mills were covered The adoption of the metric system by and closed off, so as to fu rth e r producers in January 1980, required The present: bagging is autom atic and man's role kdiminish exposure of the employees to is esse n tia lly lim ite d to m o nitorin g the m achines. dust. numerous adjustments to the packag ing machinery and the reinforcement of several machines which were not allowing fibres to escape during han Bagging has changed over the years meant to handle the additional weight dling and shipping. From this moment, because environm ental protection and pressure. the asbestos industry was to become demanded it but also because tech one of the most important customers of nology allowed it. Thus in 1970 the In fact, the conversion from 100 lb to the packaging industry in Qubec, growing popularity of containers and 50 kg bags which means an additional consuming an average of 98 sq. km of the appearance of lift trucks made the 4.4 kg of fibre, without changing the paper annually (based on an average use oTpiTiets indisperisable~to ensure dimensions of the sacks, required an consumption of 30 million 3-ply paper the stability of ffiFToads and the safety increased pressure of 55 Ib/cu. ft. as bags, before plastic came into use). \of the operations. ` opposed to 50 Ib/cu. ft. To help them Paper was gradually replaced by correct the dosage in their mixtures \ polyethylene and polypropylene, later Pallets: an industry in their own accordingly, the asbestos manufactur lined with a reinforcing fabric thread. right ing industries received samples of this In 1976, in order to further reduce From this time on, a veritable pallet m ore c o m p re s s e d fib r e b e fo re contact with the fibre and to make han industry developed near the m ines, generalized conversion to the metric dling easier, the asbestos mines began thus creating local activity which grew system was completed. to offer their customers a completely rapidly. For the customer, the pallet /) ~ ^7 . ------ ----------- -- - 7 - 7 -7 7 -- -7 ^ - TIHWrai Packaging asbestos As regards packaging, metric con version will reduce consumption of bags by about 5% for both producer and their customers. At present, this consumption can be estimated at approximately 27 million bags annual ly, of which 90% are plastic and 10% are paper. Altogether the plastic bags used on a yearly basis by the asbestos mines of Qubec (excluding the pro duction of Asbestos Hill) would cover an area of 26 sq. km. Moreover, a drop in shipping costs may also be antici pated as a result of metric conversion, `as an identical volume of fibre now weighs 5% more than before and the container which used to transport 18 tons can now carry 20 tons. Fibre shipped in biocks In spite of the considerable progress made in the last century in the area of fibre packaging, research is still being done in order to discover a technique which will ensure maximum safety in accordance with the strictest regula tions. Thus it is that Johns-M anvilie Canada Inc., after many years of arriving at the block we know today, which is compressed to 100 Ib/cu.ft. contains 4% humidity and measures 9" x12" x16" , a good deal of testing was necessary at various degrees of hum idity and with different-sized molds in which the mixing was done manually. Finally, the first machine was put into operation in the pilot plant and shortly afterward four units, with an annual production capacity of 35 000 tons, were installed at the mill. makes it possible to cut back the con sumption of paper and plastic wrap ping and to reduce the required Wrapping o f high density blocks o f fibre. research, has perfected a technique which appears to bring a solution to the few remaining safety problems posed by the handling and shipping of asbestos. Numerous tests Around 1972, Grard Lambert, Pro ject Director, perfected the process and the machine for manufacturing high density blocks of fibre. Before Although the fibre is literally lockedin by the pressure and the humidity, for maximum safety the b locks are in d ivid u a lly wrapped in paper or polyethylene and then stacked on pallets. The whole pallet can then be wrapped in plastic film if desired. Future prospects In 1981, four other machines will be installed, thus bringing the production capacity for high density blocks up from 35 000 to 70 000 tons. The advantages inherent in an expanded marketing of the blocks are twofold: safety and profitability. In bulk shipments to countries not equipped to handle containers, the bags of fibre are frequently damaged, releasing the fibre into the air and thus increasing the risk of exposure for the workers. This is the case for instance in India where the dockworkers use hooks to unload the shipments. In an attempt to solve this problem and as an experiment, Johns-Manville has just shipped 50 tons of the high density blocks of fibre to this country. Promising technique Another advantage is that this pro cess ensures a greater stability of the pallets by diminishing the height of the load, for the same weight; it also For an equal weight o f fibre, high density blocks (at right) occupy h a lf the space. storage space by half. There can be no doubt that all these factors together point to a substantial saving for fibre producers and even more for customers, particularly in terms of transport. Currently, Johns-Manville ships its entire production to the United States, Great Britain and Japan. The technical problems related the high density blocks have now been solved for all grades of fibre, as regards both the manufacture of the blocks and their use by manufacturers. Nevertheless, rare are the manufactur ing industries which are already equip ped with machines adequate enough to break up the blocks of fibre, a necessary operation before incor porating the asbestos into any kind of mixture. Even though the production capacity of Johns-Manville Canada Inc. does not, for the moment, make it possible to consider wide scale marketing of the high density blocks of fibre, the techni que is still the one for the future because of the solutions it offers for environmental problems. 6