Document YDGz8g6nJXM1zRm93q4K2X5vy

APPENDIX A PLANT MODELS A-l APPENDIX A TABLE OF CONTENTS PLANT MODELS FIGURES: Small Bulk Plant - Figure A-l Small Shape Plant - Figure A-2 Medium Bulk Plant - Figure A-3 Medium Shape Plant - Figure A-4 Large Bulk Plant - Figure A-5 Large Shape Plant - Figure A-6 Silica Brick Plant - Figure A-7 PLANT DESCRIPTIONS: Small Bulk Plant Small Shape Plant Medium Bulk Plant Medium Shape Plant Large Bulk Plant Large Shape Plant Silica Brick Plant COST OF COMPLIANCE: Small Bulk Plant Summary Cost of Compliance Small Shape Plant Summary Cost of Compliance Medium Bulk Plant Summary Cost of Compliance Medium Shape Plant Summary Cost of Compliance . Large Bulk Plant Summary Cost of Compliance Large Shape Plant Summary Cost of Compliance Silica Brick Plant Summary Cost of Compliance A-la a-2 A-A A-ll A-22 A-31 A-42 A-55 A-64 A-5 A-12 A-23 A-32 A-43 . . a-56 A-65 A-8 A-10 A-? A-20 A-27 A-29 A-37 A-40 A-48 A-53 A-60 A-62 A-69 A-71 Arthur 0 Uitlc irv,. specificacion for alternative remedial procedures and evaluation of the associated costs. Seven plant models have been developed to represent typical opera tions within the refractories industry. Each model is different with respect to individual production operations, procedures for materials handling, production quantity and product-mix. Where more than one type of product (shape versus bulk) is made at a facility, the plant is classified based upon the product having the larger annual produc tion in 1976. The following abbreviations are used to identify certain operations within these facilities: FEL -- Front End Loader FL -- Forklift Truck WSB -- Weigh Scale Bucket SC -- Shuttle Conveyors PLANT DESCRIPTION SMALL BULK PLANT Raw Materials Tabular alumina, calcined flint, clay, mullite, silica. Range of Products Castables, mortars and ramming mixes. Production Flow Raw Material Receipt and Storage Raw materials in bulk and bagged form are received by truck and rail. Bulk materials are transferred by front-end loader to open top storage bins within the main plant. Bagged materials are also stored on pallets within the same building. ; Some grog is also used as a raw material. Crushing All raw materials with the exception of grog are purchased in a classified sized form. The grog is transferred by a front-end loader from the open stockpiles to the crusher building where it is fed to an uncovered, unventilated crusher. . Batching. Mixing and Packaging Materials for batching are drawn from storage and fed into a front-end loader which transfers these to an open top weigh bucket. The weigh bucket is then transferred by forklift truck and discharged into a ventilated skiphoist which feeds the mixers. Sacked materials are added directly to the skiphoist and the discarded sacks are A-5 Arthur D Little lrxT The process description information plus an assessment of dust exposure problems were utilized to identify and evaluate the individual controls re quired to reduce employee exposures to crystalline silica. The various activities required to control these exposures to the minimum feasible level include: . Installation and operation of engineering controls; initial plant clean-up and subsequent maintenance programs; other OSHAt: related compliance activities including medical surveillance, employee monitoring, etc.; employing either a substitute for the silica setting sand or replenishing the sand more frequently. . The capital and annual operating costs for these compliance activities are presented in the following table. A-7 Anhur I) Little, In Mixing 1. Rework the enclosures and the exhausts on the wet pan, dry pan and small pan mixer. Packaging - -- 1. Replace or rework the sacking machine. General Maintenance 1. Purchase 1 heavy-duty vacuum system. 2. Initial clean-up. Demolition Capital Annual Opera tmg Cost $_______ 1 $117,090 $12,489 37,600 4,080 33,000 68,321 12,500 18,000 A-9 Arthur D Little inc Figure A-2 SMALL SHAPE PLANT A-11 Arthur D Little Inc  Batching and Mixing Batching occurs at grade level where classified raw materials are selectively added to an overhead rail weigh hopper. The batched materials are selectively drawn from silo storage, open bin stora^^--- * or from sacks. Silo materials are fed directly into the weigh hopper, while open bln materials and sacked materials are added manually. Flexible ventilation ducts are provided at each open bin station for attachment to the weigh hopper. When the batch is complete, the weigh hopper is emptied .into an enclosed bucket elevator which' raises the material to the second floor pug mill or by skiphoist to a mixer. Milled material is transferred by a set of bucket elevators to holding boxes over each of six mechanical presses. Material from the mixing is drawn by gravity and transferred to the hand mold area. Forming and Firing Six brick presses are gravity-fed from overhead holding boxes. The pressed shapes are removed by hand, stacked on drying cars, and transferred to drying tunnels. The dried bricks are transferred.Jta the periodic kilns where they are hand set prior to firing. Some materials are diverted to a hand molding process where the mix is drawn off, kneaded and hand-packed into molds. Following a setting and air drying period, racks are used to transfer the cast shapes to the dryers and the periodic kilns. A-13 Arthur Dbitie !rv The batching operation involves the manual handling of raw materials including those stored in- open bins .as well as sacks. For example, materials within bins are hand-shoveled into weigh hoppers while sacks are cut-open and their contentsdropped directly into either weigh hoppers or mixers. The storage of classified materials in open bins results in dust generation during the initial gravity feed following grinding and subsequently in the process of emptying the bin by shovel or front-end loader. The press area has large accumulations of spilled excess materials resulting from forming operations. Mixed material dries and becomes entrained in the air as a result of both foot and vehicular traffic in the press area. 'The brick finishing area also has inadequate controls to properly contain the dust generated during precision grinding and cutting operation. Finally, there are excessive dust levels within the periodic kiln which may be attributed to the reuse of setting sand which although initially sized and washed will degrade with continued reuse and pose a potential silica exposure problem. , ... A-15 Arthur D Little Inc COST OF COMPLIANCE SMALL SHAPE PLANT I. Engineering Controls Raw Material Receipt and Storage Capital Annual Operating _ Cost 1. Enclose cab on front-end loaders 4,000 Crushing 1. Enclose and exhaust crusher. 2. Install 100 feet of covered and exhausted conveyor to feed dry pan mixers. 3. Exhaust 6 open drop points Grinding 1. Enclose and exhaust 2 dry pan mixers. 2. Rework the bucket elevators feeding the screens. 58,810 40,000 6,144 1,200 69,300 10,080 78,060 31,400 8,226 3,200 Screening 1. Enclose and.exhaust the 2 vibratory screens. 2. Install 70 feet of covered con veyor to feed the storage bins. 76,000 28,000 7,800 2,100 A-17 Finishing .1 Rework the grinding machine to provide more adequate control. General Maintenance .1 Purchase heavy-duty vacuum to provide daily cleaning. 2. Initial clean-up. Demolition 31,250 3,350 33,000' 66,000 :--- 12,500 18,000 * A-19 Arthur D Utile. Inc COST OF COMPLIANCE (cor,:. - II. RECURRINC COSTS A. Annual Operating & Maintenance B. GSHA Activities C. Material Substitution Total Recurring Cost Capital . Annual Operating Costs 151,303 29, ` 37,500 $218,203 PLANT DESCRIPTION MEDIUM BULK PLANT Raw Materials Fireclay (several types), flint, Portland cement, graphite, alumina, iron oxide, titania, lime magnesia, alkalies. Range of Products Castables,- plastics, mortars, gunning mixes. Production Flow Raw Materials Receipt and Storage Bulk clays and sacked materials are delivered by truck and rail with bulk storage in open stockpiles. Sacked materials are transferred via forklift to pallet storage adjacent to the sack breaking station. Classified materials are fed directly to silo storage. Crushing. Grinding and Screening Bulk materials are transferred to the crusher by front-end loader. The operator dumps material in a feed hopper and manually starts the crushing operation. During the shift the operator alternates between feeding the crusher, monitoring the process and operating the bucket elevator. A bucket elevator transfers crushed material to the shuttle conveyor floor where it can be directed either to a rotary dryer (for drying and/or calcining) or to the grinding operation for bulk product line #1. Dried material is conveyed to a separate grinding operation for bulk product line 02. Oversized material from the screens is A-23 The batching of silo stored classified material results in the release of dust through poorly fitting connections between the silo and the portable weigh hopper. There is also a tendency for the silo dis charge valves to leak and spill material onto-the bin fls.gr area^rm^, Sacked materials are currently opened at a sack breaking station and discharged into an open portable weigh hopper. The sack breaking operation is not properly controlled and results in considerable dust generation. Also, the charging, elevation to the mixer floor, and discharging of the skiphoists results in dust generation which' contributes to overall plant contamination. The covers on the mixer pans are badly damaged and should be repaired to reduce dust generation at this location. The automatic sacking machines are poorly maintained and contribute to dust release because of excessive nozzle discharge, overfilling of sacks, sack breakage during filling, leaking seals and seams on sacks and poor maintenance and housekeeping adjacent to the filling station. The drum filling station suffers from similar problems and is also a major contributor to dust exposures within thevpackaging area of the plant. The process description information plus an assessment of dust ex posure problems was utilized to identify and evaluate the individual controls required to reduce employee exposures to crystalline silica. The various activities required to control these exposures to the minimum feasible level include: A-25 COST OF COMPLIANCE MEDIUM BULK PLANT I. Engineering Controls Raw Material Receipt and Storage 1. Provide covered storage. 2. Enclose front-end loaders Capital $216,000 4,000 Crushing 1. Enclose and exhaust jaw crusher 58,810 Drying - None Annual Operating Cost 6,104 Grinding 1. Enclose and exhaust dry grinding 2. Install covers on 800 feet of conveyor. 39,030 42,400 4,163 Screening 1. Rework and exhaust 2 screens. 2. Rework two bucket recycle systems. 76,060 31,388 7,790 3,200 Storage 1. Enclose and exhaust .14 silo storage bins. 2. Install 500 feet of covered conveyor. 254,388 200,000 36,260 15,000 A-27 Arthur D Lit lie Inc MEDIUM BULK PLANT I. FIRST YEAR COST A. Engineering -Con-erols 1. Raw Materials Receipt 2. Crushing, Grinding Screening 3. Storage 4. Batching and Mixing 5. Forming, Firing, Finishing 6. Packaging 7. General Maintenance 8. Demolition Total Engineering Controls B. Plant Clean-Up 1. Initial 2. Annual C. OSHA Activities D. Material Substitution Total First Year Cost Capital $ 220,000 247,688 454,388 399,870 " 75,200 66,000 92,000 1,555,146 $1,555,146 Annual Operating Costs 21,257 51,260 36,126 8,160 25,000 141,803 27.000 40.000 29',400 $238,203 A-29 Arthur D Little in:. MEDIUM SHAPE PLANT Lla* 1 DT BOH Lin* 2 roxxzD CCTS Us* 3 m*s  Batching and Mixing A larry car is utilized to collect sized materials which are measured into a weigh hopper and discharged at the covered wet pan. Raw materials for the specialty line are collected in the larry car and fed via screw conveyor to the batch pan. The mixer in the hand mold department is fed via a skiphoist which receives materials from both bin storage and the sack breaking station. The specialty mixer is fed in a similar fashion and the finished mix is discharged directly into sacks. Forming and Firing The stiff mud material is screw conveyed from the batch pan into the mud extruder and then pressed to shape. Materials used for hand molding are transferred to the molding floor via wheelbarrow. Here the wooden molds are sprinkled with silica sand to prevent adhesion and the mix is then hand transferred and pressed into the mold. Each of the brick presses is automatically fed from above through a wet pan conveyor. The pressed brick is then set with silica sand prior to drying and firing in tunnel kilns. t. Finishing Individual shapes may require specific finishing including grinding and sawing to achieve desired product dimensions. These operations are conducted in the brick finishing department where each selected shape is individually processed on either a brick saw, circular sander or both. A-3 3 storage bins. Both operations result in dust generation which is further compounded by the presence of uncontrolled open drop points at the bin floor level. The .batching operations generate dust during charging,of the -- , weigh hopper and discharge of the hopper to the dry pan mixer via gravity flow. The wet pan and stiff mud mixer also require preventative maintenance to reduce the level of dust generation during loading and mixing operations. The skiphoist operations for both the specialty and hand-mold departments generate excessive levels of dust during charging, elevation, and discharge into the mixer. These mixers are also.poorly maintained and the inadequate levels of exhaust ventilation contribute to the release of silica dust. The present procedures for filling sacks in the specialty department result in considerable exposure to dust. This situation is directly related to overfilling of sacks, leakage through broken seams, and lack of good housekeeping in the area adjacent to the sacking machine. Current procedures for sack breaking and disposal of- ecq>ey sacks contribute to dust generation and exposure to silica flour and related materials. Finally, the application of silica sand as a setting material during firing of shapes results in exposure to silica. * Jfbjdt I. PURPOSE OF THE QUESTIONNAIRE The purpose of the attached questionnaire is to obtain sufficient information about plants making refractory products to enable a determination of the impact of a proposed OSHA standard for silica dust. The information sought falls into three general categories^- plant process economics of operation current worker health records and procedures. To the extent possible, Arthur D. Little, Inc., has tried to minimize the number of questions and amount of proprietary information requested. As described in the cover letter, all data wll be kept confidential for an individual plant and used in aggregate form only in Arthur D. Little's final report. All individual responses and data will be destroyed by Arthur D. Little at the conclusion of this study. To assist you in understanding the purpose of the questionnaire, a brief description of the purpose and objectives of each section follow: I. Identification (Corporate Information): This section identifies the corporation and the individual who completes the question* naire. Item B identifies the refractories plants for which questionnaires are to be completed. Companies with more than three plants should complete questionnaires for their repre sentative plants. II. Plant Information A. Identification: This section identifies the plant. i B. Product Mix and Production Process: This section seeks information on the product mix, raw materials used, and production process at the plant. This information is useful and necessary to understand the potential for worker exposure to silica as well as to provide product characterization and data on the economics of operation for the plant. C. Revenues and Expenses: Pro-forma expense figures (expenses as a percen tage of sales) are requested in order to construct aggregate plant operating profiles. This information will be used to assess the impact of the cost of OSHA compliance activities upon plant costs and product prices. For exam ple, one measure of the impact of an OSHA regulation is the increase in 5. AJ1 questions should be answered by checking the appropriate box or boxes. Those questions requiring a written response should be answered by printing or typing in the appropriate space. 6. Attempt to answer all questions. Where appropriate, answers should be provided for the most recent fiscal.year. Ifyou cannot provide a'full resportiF=^"t to a question, answer as much of it as you can. If a question is not relevant to your plant operation or the information requested is not obtainable, please provide an explanation. If clarification or supplementation of any response is necessary, please attach a separate sheet. If you do not know the answer to a question, write "don't know" or "DK". If a value is zero, write in zero (0). 7. If you have difficulty understanding or answering any. question, please cal! Stuart Young or Scott Stricoff at 617-864-5770. 8. Please retain a copy of your completed survey, since it may be necessary to contact you in the future to verify your responses. III. DEFINITIONS A. Economic Accumulated Depreciation - Total depreciation to date or the difference between original book value and current book value. Annual Cost of Pollution Control and Other Envi ronmental Regulations -- Depreciation charges for pollution control equipment or for plant and equipment modifications required by regulations. Operating costs include the cost of maintenance and operating labor, supplies, fuel, and electricity required to operate the equipment related to the regulation. Depreciation - Annual book depreciation of assets at tills plant. Direct Wages, Salaries and Related - Payroll costs (salaries, wages, unemployment insurance, FICA and other related costs) of direct labor (produc tion employees) engaged in the manufacture of refractories products. Fixed Assets - Capital assets, plant site land, and equipment are all categories of fixed assets. The bock values or values net to depreciation or deple tion should be shown. Gross Fixed Assets -- Original book value of Fixed Assets. Materials Cost -- Chemicals and other supplies used in the production of refractories products. Operating Margin - Earnings before interest, taxes, general and administrative expense. OSHA - The Occupational Safety and Health Administration. Other Income (Expense)- Income (expense) not directly or indirectly associated with refractories product manufacture. Production Workers -- Direct and indirect labor engaged in and attributable to-the production of refractories products at this point. Profit After Tax - If this is a single-plant com pany, the net profit remaining after Federal Income taxes. If a multi-plant company, calculate an approximate profit after tax by using the company's aggregate tax rate. Profit Before Tax - Sales less all costs, except Federal Income Taxes. - *- Codes 1013, 1015, 1017, 1019-lnsulating fire brick and dupes - The subdivision of codes 1013, 1015, 1017, and 1019 should be made in accordance with the ASTM Gassification C-155, the respective groups being 16, 20, 23 combined with 26 and 28 and higher. Code 1025-Refractory bonding mortan, wet and dry types - Include both "air-'setting and heat* setting bonding mortan which contain up to 60% A1203, dry basis, by analysis. Report bonding mortan which contain more than 60% Al2 03, dry basis in code 2020, "High alumina mortan." Code 1026-Plastic refractories and ramming mixes, up to 50% Al203 - Include products referred to as plastic fire brick and the less plastic materials intended for ramming into place after the addition of water (when shipped in dry form) containing up to 50% Al203. Report products containing over 50% to 87.5% Al2 03 in code 1028. Code 1028--High alumina plastic refractories and ramming mixes, containing over 50% to 87.5% A1j03 - Exclude plastic refractories and ram* ming mixes of mullite or extra high alumina. Report products made of these materials in code 2028. "Other nonclay plastic refractories and ramming mixes, wet and dry types." Code 1030-Gay castable refractories (hydraulic setting), up to 50% Al203 - Include hydraulic setting castables made from calcined fireclay, diaspore or bauxite base, and Portland or calcium aluminate cements containing up to 50% AI203. Exclude high alumina castable refractories over 50% A1203. Report these in code 1032. Also exclude castables based on mullite, fused or tabu* !ar alumina, or other nonclay materials. Report castables made from these materials as nonclay refractories in code 2023. Code 1032-lfi^ alumina castable refractories (hydraulic setting), over 50% Al203 - Exclude mullite and extra high alumina castables. Report these products as nonclay refractories in code 2023. Code 1036-Fireclay gunning mixes, up to 50% Al, 03 - Include alumino-silicate compositions up to 50% A1j03 specifically engineered for gunning applications; may include hydraulic setting or other chemical bonding agents. Report composi tions over 50% AJ203 in code 1038. Code 1038-High alumina gunning mixes, over 50% to 87.5% A1203 - Include alumino-silicate compositions over 50% to 87.5% Al203 specifi cally engineered for gunning applications. Exclude mullite and extra high alumina materials which should be reported in code 2032. Codes 1040 and 1042-Other clay refractory materials - Include in code 1040 domestic ship ments of materials for direct use as finished refractory products, and all exports. Exclude from code 1040 all domestic shipments or transfers to plants of your company or to other companies for reprocessing in the manufacture of brick or other refractories. Report these domestic shipments in code 1042. 2. Definitions ofNonclay Refractories NOTE: Molten cast refractories are made by fusing refractory oxides, as in an electric furnace, and pouring the molten material into molds to form finished shapes. Codes 2004,2006,2008--Magnesite and magnesitechrome brick and shapes (magnesite predominat ing; products analyzing greater than 55% MgO) Include in code 2004 all pitch-bonded magnesite and magnesite-dolomite brick (magnesite predom inating), even though baked or tempered, but do not include burned impregnated brick, which are to be reported under code 2006. Report dolomitemagnesite brick (dolomite predominating) in code 20Id Exclude molten cast magnesite and magnesitechrome brick and shapes as well as those made of fused magnesia. Report products made by these methods in code 2017, "Other nonclay brick and shapes." Code 2010--Chrome and chrome-magnesite brick and shapes (chrome predominating; products analyzing no more than 55% MgO). - Exclude molten cast chrome and shapes. Report products made by this method in code 2017. "Other nonciay brick and shapes." CONFIDENTIAL REFRACTORIES INDUSTRY SURVEY 1. CORPORATE INFORMATTON A. IDENTIFICATION 1 - Company Name: 2. Corporate Headquarters: _. Street City 3. Person Completing Questionnaire: a. Name: b. Title: State .~ Zip 4. Attach a copy of the company's most recent annual report or available financial statement. B. REFRACTORY PLANTS Please list the refractories plants that your company operates: Complete Part II for each refractory plant up to three plants. Companies with more than three plants should complete the questionnaire for three representative plants. It is desirable that the plants selected represent the sire distribution of your refractory plants or other characteristics which give rise to differences in worker exposure to free silica. Arthur D Utile Inc b. Type of Grinding Equipment Dry Pan Gyratory Crusher Jaw Crusher Roll Mill Ring Roll Hammer Mill Rod or Ball Mill Other Type (Specify) Totji Tons patting through each type of mill in 1976 . c. Size Classification Equipment Tom Paaing in 1976 All Screening Units All Air Classifiers ___________________ __________________ _ 5. If shapes are produced at this plant, what portion of the total units are produced by the extruded versus pressed process? i Percent Total Production (Short Tom) I0 Under 25% 26-50% 51-75% Over 75% 100% Extruded 0 aOaa I Power Pressed a a n --d At what capacity utilization rate was this plant operation in 1 976? 1976 Production as Percent of Capacity 1 Under 50% 51-75% 76-90% Over 90% Bulk Refractories Brick and Shapes aa O Arthur D ' jule Six 10. Average number of employees during 1976: Under 10 11-30 Production Workers Other Employees D 31-50 . 51-75 D 76-100 D a 101-500 Over 150 Da CK C. REVENUES AND EXPENSES 1. Income Statement Please check the box which most closely approximates your costs as a percentage of sales. (1976 or most recent fiscal year) This Plant's Cost as an Approximate Percent of Sales <10 10-19 20-29 30-39 40-49 >50 a. Direct Wages, Salaries and Related D a <20 21-29 30-39 40-49 b. Materials and Supplies a a a < 1 2*3 3-4 4-5 c. Depreciation 0aa d. Workers Compensation Insurance D a e. Other Plant Expenses (Including rent, fuel energy, other insurance and property taxes) a D <10 11-15 16-20 21-25 f. Operating Margin D < 7 8-10 11-13 14-16 g. Selling, General and Admin. (Including allocation from Parent) a 50-59 5-6 X 26-30 17-19 a >60 O >6 D >30 >19 i - Arthur D bulc it>: ir 2. What are the Annual Depreciation Charges on this equipment? S 3. What are the Annual Operating Costs associated with this equipment? $ F. OCCUPATIONAL HEALTH RECORDS AND PROCEDURES I. Evaluation 'of Refractory Plant Personnel Data a. How many years after a worker terminates employment are his personnel records kept on file? yean b. Do these records include the following information for each employee? (Check if Yes) Date and age of employment Durations and descriptions of jobs held Durations and levels of free silica exposure Date and age at termination of employment Reason for termination of employment (e.g., job change, retirement, injury) Home address c. Do most production employees terminate employment before reaching retirement? Yes D No D d. Do most production employees terminate employment for health reasons? Yes O No O If not, why do they quit? _____________________________ ________________________ _________ e. What is the average length of employment for production employees? years f. How many workers have received worker's compensation for silicosis in the past five yean? g. How does this compare with previous years? Higher Same Lower C3 h. If there have been changes in the number of worker's compensation awards for silicosis, what factors are responsible? -7ArthurDbule Inc i *m d. Section 4 - Personal Protective Equipment i. Are employees provided with respiratory protective equipment? Yes O No D ii. If yes, what percent of your employees use them?% __ iii. Where exposure to free silica is above the recommended limit, is work clothing vacuumed before removal? Yes No e. Section 5 - Hazard Information i. Are employees informed about the hazards of silica and the appropriate precautions for its safe use? Yes No O f. Section 6 -- Work Practices and Controls Please specify if local exhaust ventilation (e.g., with a dust collector) is used in the following plant areas: Used Not Used Grinding and Crushing Operations a a Screening Storage Areas Mixing Operation Bagging Operation a Forming Operation Qa Firing Operation a ! Other Operations (specify1 ! ii. Do you process silica to eliminate the respirable panicles? 4 Yes No i iii. Have you changed from dry to wet processes? 1 Yes D No iv. Do you use process enclosures? Yes No O -9- * i ATTACHMENT A Product Code 3255011 3255015 3255021 3255031 3255035 3255041 3255045 r u 3255026 3255027 i 3255023 1 3255024 4 3255047 I 3255049 } 3255053 1 Item Description Item Code Produced at Want CLAY REFRACTORIES Brick and shapes Fireclay (including semi-silica) brick and shapes, except as listed below 1001 Superduty fireclay brick and shapes High alumina brick and shapes (50% Ai*Oj and over) made substantially of calcined diaspore or bauxite (Exclude mullite and extra high alumina refractories, which should be reported in codes 2009 and 2011.)' Ladle brick (containing less than 50% AljOj)1 1003 ' 1005 1006 Q D High alumina ladle brick (containing 50% or more AJ2 03), previously reported in code 1005* 1008 Sleeves, nozzles, runner brick, tuyeres, and slide gate brick (externally applied)1 Glass-house pots, tank blocks, feeder parts, and upper structure shapes used only for glass tanks (Exclude mullite and extra high alumina refractories, which should be reported in codes 2009 and 2011'f 1009 1011 Insulating fire brick and shapes1 ldOO^F to 2000F (but not including 2000F) 2000F to 2300*F (but not including 2300F) 2300CF to 28O0F (but not including 2800F) 2800* F and higher Hot top refractories Clay kiln furniture, radiant heater elements, potters' supplies, and other miscellaneous shaped refractory items 1013. 1015 1017 1019 1021 1023 Q a Refractory bonding mortars (up to 60% A1203, d*y basis by analysis), wet and dry types1 1025 -1Artluit i' i nt It* I: Product Cod 3297016 3297017 3297018 3297021 3297033 3297035 3297052 3297053 3297048 3297049 3297055 3297057 3297058 Item Description NONCLAY REFRACTORIES (Continued) Magnesite and magnesite-chrome brick and shapes (magne site predominating; products analyzing greater than 55% MgO.) {Exclude molten cast and those made of fused magnesia, which should be reported in code 2017.)' Pitch-bonded Pitch-impregnated Others Chrome and chrome-magnesite brick and shapes (chrome predominating; products analyzing no more than 55% MgO.) {Exclude molten cast, which should be reported in code 2017.)' Graphite crucibles, retorts, stopper heads, and other shaped refractories containing natural graphite Carbon refractories; brick, blocks, and shapes, excluding those containing natural graphite Mullite brick and shapes made predominantly of kyanite, sillimanite, andalusite, or synthetic mullite (Exclude molten cast, which should be reported in code 2017.)* Extra high alumina brick and shapes made predominantly of fused bauxite, fused or dense-sintered alumina {Exclude molten cast, report in code 2017.)' Silicon carbide kiln furniture (made predominantly of silicon carbide) Silicon carbide brick and shapes (made predominantly of silicon carbide), except kiln furniture Zircon and zirconia brick and shapes (made predominantly of either of these materials) Dolomite and dolomite-magnesite brick and shapes and other brick containing a substantial amount of dolomite grains1 Other nonclay brick and shapes not included above (e.g.. molten cast, forsterite, pyrophillite, etc.)1 Item Code Produced at Plant *. -- 2004 2006 2008 2010 O . 2013 2029 2009 2011 2012 > ------ 2014 2015 2016 2017 -3- Arr APPENDIX F MISCELLANEOUS TABLES APPENDIX F TABLE OF CONTENTS MISCELLANEOUS TABLES TABLES: Dust Sampling Results - Table F-l Dust Sampling Results- Table F-2 Dust Sampling - Table F-3 Respirable Free Siliea Sampling- Table F-4 Respirable Free Silica Sampling- Table F-5 Respirable Free Silica Sampling- Table F-6 Weight of Refractories - Table F-7 -* F-2 F-3 f-4 F-5 F-6 F-7 F-8 F-9 * so -y w cn *y fi cn >.j o o o -< t- v A I dust s a m p lin g results CO N 01 4) Li u- 8 o H *-e ft H S CO -- u 41 3 41 u Is- XJ ta 3 O f-3 H 'v. qM XJ E O nJ H ocH ^c XJ -L eg E Ul N-- 3 C o y o vO e_ o CN or-. vO V * r- vO cn CN CN COl N5 o r-i V r*. C-) en H y vO -y cn * O r- co vO y i--i vO *y Cl m NT Ci CO4 -y CN o o iH o o CN O o Ci tn o rN o CN H m co CN ro>. m cn in vO CN CN CN I 1 1l 41 to c <s w H eg Cl U >4 -H eg c eg o 41 c c 41 g g o o 41 Li 03 *o 41 41 41 X 41 41 i-L P eg Lc a 0) 41 Li 41 to 3 eg to CO. 1 O n . 4) P eg L- a 03 41 W A eg eg 41 41 0) i-H 04 cpB. e4 a: c4 o < CO O eft P a o CO o 0 P a P en o 03 o a H Lt eg H 03 1 eg co 41 nS i. 41 - < 4-> NV . Q XJ 4 U 41 Q o (= u 41 Ll` o uo u 4 L- E o XJ 41 to XJ CL c eg ' XJ c >. V- CL ^4 > c eg c Cl <g c ci 4! to H u 4) eg > (ft. (A co H H H c<og H L4 to 41 a. Vu a u c 41 oP to eg w E Li T3 41 cs oo 2 <4 c o CO O -H H T3 c Li <u c 41 tco 4) Li eg 41 ft41 (*- u 41 u o o o 04 o w u- cXJ o eg eg 01 eg ^4 H u XJ XJ -H c o o(A c41 3 *-N *--( &- O ft- XJ XJ J= a < 03 w o 03 4-1 eg H 41 u 41 41 c ee Li c41 U O Ij C 41 P & >, H L- Lao Sa 3 t-i JZ a CO 4-1 eg eo eg ft. 41 Li ft- a E eg wP c CN 4 U CO CL CL P M O c o 4J eg Li U C 41 U e o o 41 H a eg L< CL 03 41 Li l 04 jS. W s_x F-3 t~\ i (2 ) Samples observed to c o n ta in some la rg e p a r tic le s w hich should have been excluded; by the c y c lo n e . C o n c e n tra tio n s 'a re o v e rs ta te d fo r these samples by as much as 10-20 p e rc e n t. * cn \C r-. o U*l cn >E x 3 esi <n J "-a HM oOo <n E w o CO o c*l cn v <H l j J N rt N p40>) u* <II ej o .-ten H E CO -* Of 4> =1 41 U lu n CO m cm r-* r- 3 rn u- X l/*5 x III DUST SAMPLING p (0 3 y-N Ct cn E au *j E O H m CM cn CO CO <n \ w 3 CO cn ,, o CO CO 3 co CM <y> x CO CM cn 3 CM c o cn CNJ cn i-( CM e O /"< c P rt mm m O O Cn | I l i <0 E *3 3 3 3 cn P a t 4) o H MS y--s y-s aj P \ V CM CM CM W M/ xa CM w A R R a E <0 os os < OS 02 02 02 n 02 02 `o- C9 02 - -- o 0& CO <s 4) P 60 < c P C *T3 la 4) 4) E O 60 C <a P Je P* c <0 V P o 4) la Pa CO JS P u< P Q. 4> 4> 4) J* a c 05 P w 3 4) <9 P 41 a a> p . la la 45 a P O a w a3 3 CO c 0} P OS 0) <Q 4) ffi W 3 O O Oe H 6c0 *H o 02 P --( U* la P so Cn P c c 4J u P a 4) JN p P E u* eo 5 o r-i la *-> cn P la o o e a. E 4-1 a O 4) p O 3 CO os a c c 41 E- 73 g P c *r4 41 <9 p 3 a- CO o p u O' < V Q (0 p fti 05 45 OS. as _ n--y F-5 w N rt to c o u W 3 *3 o Jm Cm *U c c c c pH 4_l o re zI--< u V &pj c. o * 4_S CO c re M<u C- i fa.inI tCp--JOI w >n <*N E fal 2 **> 60 f ee fc. 3 <6- fpaJl C in C3 i 2l n Cm to hcsi eO i in CM A 05 re ! pH C. c re to 4_l c 0) re U. 11 c- i ( re CO m CO O O CO r- 4J pH pH ' f> r--< pH o H U pH r* m 09 m c o CM pH CM pH CO CM to re 60 O sO o o o o * u pH pH re ^H 3 r- cn m cn r*. ON re CM pH CM pH pH re r --< ph CO pH o o O n CM re m CM pH E CO re e 0 pH 4J re |M 60 re eC o ^H 60 ph .3 C U 0) H c3 X u l- 60 MM p re o c x c. 1 pH E re pH o. o re 3 O re c o oo c 60 0 c re c re c fa. pH 60 pH h re pH fa c pH re re JO re pH re e re o re re u H to J-l re re re re re re lM mH re pH 03 Cm hi to s pJ < H O H E3S C c ., ' ~ re ' "* - re o o C 4J re re c O pH re s re o oc re re 4J "O re ^ re x. re re re pH g pH O pH 1m re mh re *o re re U TJ Mm 3 pH o re cX re JZ re re pH >m 3 re >-scn <- E SH *>, 60 re 3, re pH in CM E re a re e o pH re re c re M >H U C re re pH re 4-> re--- 4J o pH re pj re pH re JM U 3 re re 4J 4J !h re < -o /p H Arthur D Uttic !r\*. Type Fireclay Superduty High Alumina Insulating Firebrick WEIGHT OF REFRACTORIES (1) Lbs. Cubic. Foot 1 (2) Lbs. per. Brick 1 (3) Average lbs. Brick 3 120-140 130-150" 125-150 7.05-8.20 7.62-8.79 7.32-8.79 7.6 8.2 7.9 19-60 1.11-3.52 2.4 (4) Brick Ton Refrac 263 2^4 250 833 Silica Brick 100-110 5.86-6.44 Magnesite Brick Burned 160-165 9.37-10.25 Bonded 180-185 10.55-10.84 Chrome Brick Burned 180-190 10.55-11.13 Bonded 180-195 10.55-11.43 Silicon Carbide 136-158 t Fosterite 150-160 7.99-9.26 8.79-9.37 I Zircon Ladle Brick Mullite i i 6.2 9.8 10.7 10.8 11.0 8.6 9.1 13.0 8.0 8.0 204 187 ^ 183 233 219 154 250 250 ^Brickwork Construction, o ^Coi. 1+17 9" equivalents. ' ^Based upon distribution of production (e.g ADL estimate. p. 397. insulating firebrick) or F-9 A r-V-.T irHI r* rl= I COST 0? COMPLIANCE LARGE SHAPE PLANT I. Engineering Controls Equipment Annual Operaci ; ___ . .Cost Raw Material Receipt and Storage 1, Provide covered storage for up -to 2 months supply of selected raw material. $900,000 2. Enclose cab or front-end loaders 20,000 Crushing 1. Cover and exhaust both the jaw and roll crushers. 2. Cover 200 ft of conveyor feeding crushed material to grinders. 117,620 10,600 12,200 Grinding 1. Enclose and exhaust grinders. 2. Rework 5 bucket elevators feeding screens. Screening 1. Enclose and exhaust 8 screens. 2. Install solid floor in screen room. 3. Rework recycle system Storage 1. Enclose and exhaust 42 storage bins and silos. 2. Install 250' of covered exhausted conveyor. 234,000 78,470 25,000 8,000 304,210"* 30,900 108,000 - 15,600 - 936,000 166, '-;0 80,000 12,500 4 -J 1J 1 J ] Jj 1 2 Classified materials are fed to open top storage bins which result in dust generation during feeding and discharge of the bins. Batched materials are fed to the individual mixers via open conveyors with a series., of_open drop transfer points which pro-duce excessrve"~`' levels of dust. The mixer is improperly exhausted and the rates of local exhaust are insufficient to properly control this operation. Also, the mixer covers are often left open to assist in visual observation of this process, a practice which enables dust to escape into the mixingbatching area. Mixed materials are fed to press feed bins where spillage from both the feeder system and bins result in dust generation. There are also considerable accumulations of excess feed materials at the front and rear of the press which upon drying can become suspended due to vehicular or foot traffic. Additional exposure to silica include those associated with the use of this material as a parting sand during setting operations prior to firing the green brick. The process description information plus an assessment of dust ex posure problems was utilized to identify and evaluate the individual controls required to reduce employee exposures to crystalline silica. The various activities required to control these exposures to the minimum feasible level include: Installation and operation of engineering controls; initial plant clean-up and subsequent maintenance programs; other OSHA related compliance activities including medical surveillance, employee monitoring, etc.; PLANT DESCRIPTION LARGE SHAPE PLANT Raw Materials Fire clays, bauxite (raw and calcined), kyanite, iron oxide, alumina, additives and bonding agents. Range of Products Standard brick and shapes, nozzle blocks, formed sleeves. Production Flow Raw Materials Receipt and Storage Raw materials are received by truck and rail. The majority of the materials arrive as raw bulk with a smaller percentage of classified materials. Some of the raw materials are sent to classified storage while the remainder are open stockpiled. Sacked materials are transferred by forklift to storage on pallets. Crushing, Grinding, and Screening Raw clays are crushed with a portion of the material being passed through a rotary kiln. Crushed raw materials are then further classified through grinding and screening with this product passed to intermediate storage. Oversized materials are recycled from the screens to grinding to maintain uniformly sized raw materials. Batching and Mixing Classified materials are batched via a conveyor and weigh hopper system and transferred to the mixer. The materials discharged from the mixers are conveyed to the press feeder bins via a surge hopper. ] ] 3 3 I I 1 A-56 J Arthur D Litt v 1/'/ r v /-*'c II. RECURRING _COSTS .A. Annual Opera tin;* & Maintenance ,B. OSHA Activities C. Material Substitution Total Recurring Cost B K<|uipmcnc t. Annual ^ Opcratinc Costs 365,341 $375,441 i 8 i f A-54 IArthur!) i Packaging 1. Automate drumming operation on line 1 to remove manual shoveling- of wet material 2. Rework screw conveyor on line 2 feeding extruder 3. Modify screw conveyor feeding sacking machine on line 3 4. Install automatic system for truck loading on line 4 with 100 feet conveyor, screw feed from silo and 2000 CFM 5. Upgrade the screw conveyor on line 5 feeding the bagging machine 6. Rework screw conveyor feeding extruder 7. Rework the sacking machine on line 3 8. Rework the sacking machine on line 5 General Plant Maintenance 1. Initial cleanup 2. 3 vacuum systems Demolition Electrical 1. Initial construction of electrical transformers. Capital Annual Oneratinz $ 20,000 $-- 3,000 2,000 40.000 7,604 22.000 2,000 -- 1,200 572 3,200 2,000 37,600 37,600 -- 4,080 4,080 99',000 244,000 _54,000, 37,500 -- 20,000 9 w* k i A-5 2 8 Arthur D Litter Capital Annual Operating Co Storage 1. Modify 5 open bins on line 3 to enclose and exhaust. S 145,000 $ 11,000 2. Modify 6 open bins on line 4 to enclose and exhuast. 3. Rework 12 silos on line 3 to enclose and exhaust. 174,000 * 218,000 13,200 31,000 4. Install two 30-ton capacity silos on line 4 to replace open bulk storage. Add dust collection system. 5. Upgrade the exhaust ventilation and discharge valves on hopper storage for line 5. 40,000 29,260 4,600 29,260 -- 3,200 -- 3,200 6. Upgrade the existing silo storage to improve exhaust on line 6. 144,000 20,000 Batching 1. Replace existing manual handling of materials on lines 1 and 2 with a tote bin system.* 109,850 46,000 2. Replace existing sacking station on lines 1 and 2 with new exhaust design 53,515 4,720 3. Modify the skiphoists feeding the wet pans on lines 1 and 2 55,152 55,152 5,800 5,800 4. Replace the batching system on line 3 with a tote bin station 59,850 4,600 5. Upgrade skiphoist feeding dry pan on line 4 6. Eliminate FEL on line 4 and install 100 feet of exhausted conveyor to discharge feed from dry pan to bulk storage 55,152 40,000 61,448 5,800 1,200 5,000 Includes 50 tote bins. A-50 Art COST OF COMPLIANCE LARGE BULK PLANT I. Engineering Controls Raw Material Receipt and Storage 1. Install covered and enclosed storage for raw materials fed to lines 4, 5, and 6. Capital Annual Operating Cost $ 720,000 2. Install 230 feet of covered conveyor from raw storage to grinder on line 3. 3. Cover conveyor on line 3 from crusher to kiln 100 feet. 4. Install 100 feet conveyor to feed covered raw material to crusher on line 6. 5. Enclose 5 front-end loaders Crushing 1. Cover and enclose the jaw crusher on line 3 and the roll crusher on line 6. 2. Upgrade conveyor on line 5 from crusher to dryer. Cover and ex haust at 3000 CFM. 3- Install conveyor on line 6 to feed crushed material to grinder. 80,000 6,000 5,300 40,000 3,000 20,000 117,620 12,208 37,000 l 33,000 4,800 4,800 Kiln and Drver 1. Add 200 feet of conveyor to transfer calcined material to bin storage on line 3. 2. Upgrade conveyor on line 5 from dryer to hopper storage cover and exhaust at 3000 CFM. 80,000 6,000 4,000 33,000 4,800 i i i A-48 Arthur D Uffe scmmaHi ccsi of ccy_-i:.-c>CL MEDIUM SHAPE PLANT I. FIRST YEAR COST A. Engineering Controls 1. Raw Materials Receipt 2. Crushing. Grinding Screening 3. Storage 4. Batching and Mixing 5. Forming, Firing, Finishing 6. Packaging 7. General Maintenance 8. Demolition Total Engineering Controls B. Plant Clean-Up 1. Initial 2. Annual C. OSHA Activities D. Material Substitution Total First Year Cost Caoital 364,000 412,870 572,660 376,274 31,250 37,600 99,000 132,000 ,025,654. v $2,025,654 Annual Operating Costs 33,604 43,700 32,852 3,370 4,080 37,500 158,906 27.000 40.000 ----- 79,074' ' 105,000 $409,980 - -* i .j A-40 Arthur I ) I iti I Storage 1. Exhaust and enclose 8 silos. 2. Enclose and elevate 6 open storage bins. 3. Instair'300 feet of conveyor to feed bin. 4. Cover and exhaust 10 open shuttle drop points on bin floor. 5. Enclose and exhaust 8 open bins. Batching 1. Install tote bin system to replace current design. 2. Rework 2 skiphoists feeding specialties mixer and hand mold mixer. Mixing 1. Cover stiff mud batch pan fed by Larry Car. 2. Cover wet pan fed by Larry car. 3. Rework specialties mixer. 4. Rework wet mixer in hand mold department. Forming - None $125,040 174,000 12^,000" 153,620 12,800 13,200 T9,006"" 12,500 109,850 110,304 4,600 11,600 39,030 4,163 39,030 39,030 139,030 -- 4,163 4,163 4,163 Firing 1. Material substitution or more frequent replacement of setting sand. 105,000 A-3R Arthur D APPENDIX E QUESTIONNAIRE The following questionnaire was employed to collect input informa tion regarding current financial statuses and operating con33Ltions'^of individual plants within the refractores industry. i i Arthur DbBef Table D-2 MODEL INCOME STATEMENT SMALL SULK PLANT Production; 15,000 TPY Sales; $2,000,000 Plant Book Value: $1,000,000 Sales Cost Goods Sold Direct Mages Materials/Supplies Depreciation Workers Comp. Other Plant Expenses Total Cost Goods Sold Cross Margin Selling, G&A Interest Profit Before Tax Profit After Tax 100 27 40 2 1 10 80 20 12 0 8 4 $1,750,000 $750*000 Marginal Plant 100 33 45 1 2 14 95 5 10 0 (5) (3) D-4 Arthur DU APPENDIX D FINANCIAL STATEMENTS The individual pro-forma financial statements developed from the questionnaire survey data, and other sources including-annual r-epoe^sare presented in the following tables. Both balance sheets and income statements were developed to evaluate the current financial health of the industry at a point in time and its ability to finance compliance activities based upon current cost position. r-2 Arthur DL'_1 employer muse inform these employees of the hazards of the silica ex posure, of the information contained in the OSHA standard, of emergency procedures, of the purpose, proper use, and the limitations of any per sonal protective equipment,and the operations which could result in a substance exposure in, at; or above the action level. ~A copy of the regulation and the appendices must be made available to all exposed em ployees ,, The cost of training can be summarized as follows: Preparation cost: 4 hours per facility at $20 per hour to gather and prepare the information necessary for the training program $80 per facility Cost of materials: Copy of the regulation and appendices at $0.10 per page, 5 pages .50 per employee Training costs: To train 20 employees at each facility requires 1 hour of trainer's time at $20 20 per class Plus 1 hour of each employee's time at $14 per hour* 6 14 per employee Total Training Cost Per Facility * 80 + 20 x # classes + 14.50 x Total Employees where number of classes * Total Employees/20 6. Recordkeeping The contemplated regulation requires that the employer keep records concerning exposure determinations and measurements, mechanical venti lation measurements, training, and medical surveillance. The first three of these four record systems will be maintained for each facility. Recordkeeping will require intermittent one-line up-dates and can be maintained by a clerk expanding two hours each year at $8 per hour. The total cost each year for the facility-specific C-12 i Arthur D Lit The labor costs associated with conducting the measurements can be summarized as follows: Measurement at L points, 4 times per year 15 minutes per measurement @ $10 per hour plus 100Z overhead $ 20 L 3. Signs and Labels The proposed regulation requires that certain signs be placed at entrances and access ways to areas where employees may be exposed to silica in excess of the action level, and other signs must be placed In any work area where employees may be exposed in excess of the action level. The cost of a metal sign containing three lines and ten words is needed per facility, the total cost is $67.50 per facility for the required signs (first year only). The new regulation also requires that precautionary labels be applied to all containers, packages, or equipment containing free silica* As a minimum, these labels must contain the word "warning" or "caution", and a warning against being exposed to silica through inhalation. 4. Medical Surveillance Where employees are exposed to free silica above the action level, medical surveillance is required prior to employee placement and at ` least once every three years thereafter. A medical history will be required and a physical examination will be called for including speci fied tests or organ system examinations. C-10 Arthur D Li Monitoring equipment Calibration Initial determination Total Exposure Measurement 450 10 112 E + 56 450 + 112 E + 66 (b) Recurring costs Facilities are not required to monitor employee exposures below the action level. Recurring monitoring costs for employees below the action level is zero. (2) Initially Above the Action Level (a) First-year costs The employer purchases monitoring equipment, calibrates the monitoring equipment, makes an initial measurement and then follow-up measurements during the first year. The costs for these activities are as follows: Monitoring equipment 450 Calibration (4 times) 40 Initial measurement 112 E + 56 Follow-up measurements 3 ri!2 E above + 56] Total Cost Exposure = 450 + 4 [112 E + 66] (b) Recurring costs The employer is required to monitor employee exposures above the action level on a monthly basis until such time as the employee exposure is reduced below the recommended standard. The costs for this C-8 Arthur D where E * (Number of workers x .5) * Number of shifts 1,4 Follow-up Measurement Follow-up.measurements must be performed if the firs'measurements' reveal that employees are exposed to concentrations at or above the action level. If an employee's exposure is determined to be at or above the action level but below the permissible exposure limit, follow-up measurements must be performed at least biannually. The cost per faci lity for each follow-up is the same as above except that the follow-up measurements are required only for that portion of the sample above the action level: Sample labor Sample collector Sample analysis Cost of Follow-Up Measurement 40 E above + 20 2 E above + 1- 70 E above + 35 112 E above + 56 1.5 Calibration In order to carry out the initial exposure measurements and the follow-up measurements, sampling pumps must be calibrated periodically. This-typically is done by the person engaged in sampling, and each calibration takes 30 minutes at $20 per hour. At each facility, the pump will be calibrated once at the time of initial exposure measure ments and once at the time of each of the N follow-up measurements. The total cost for calibration is $10 (N + 1) per facility. Calibration Labor Cost Per Facility $10 (N + 1) C-6 Art hi ir Pi measure Che exposure level of that employee nose likely Co have che greacesc exposure ac each operation for which a positive determination has been made. Measurements-must be performed so that the sampled employee's-- actual exposure averaged over an 8-hour shift can be determined. This is best done using personal sampling devices which collect samples from the.employee's breathing rone. Such devices normally consist of a sample collection device (filter cassette) worn at the lapel and con nected by flexible tubing to a calibrated sampling pump normally worn on the belt. While there are a variety of pumps available, they generally are priced between $300 and $400. The following pump and calibration kit are representative of those available. Pump, Bendix, Model BDX-44 ($310) and charger ($40) Calibration kit ($98), including bubble meter, tubing, stopwatch Total Equipment Cost Per Facility $350.00 100.00 $450.00 (2) These relatively small costs will be "expensed" in the year of their purchase, thus yielding a cost of $450 per facility in the first year. Filter Sampling for Particulates The procedure most commonly employed in NIOSH methods for collection and analysis of particulates involves sample collection in a 37-mm filter cassette using a membrane filter supported by a cellulose C-4 Anhar D Ut APPENDIX C OTHER OSHA COMPLIANCE COSTS This Appendix presents a generalized methodology developed ADL to assess the OSHA compliance costs for any occupational health regulation. In this instance it was applied for crystallize silica to estimate the costs of compliance for the proposed regulation. These formulations reflect a computational procedure developed to evaluate compliance costs for situations where more than one contaminant is found in the occupational environment. However, the methodology is directly applicable to the assessment of the complaince costs associated with the silica regulation. C-2 Ar;h; " O Operating and Maintenance Costs General Ventilation Total Operating and_Haintenance Costs $ 1,000 4,800 $.3,800:.- = i i \ ! t1 5-49 Arthur D Little Inc 12d. SKIPHOIST OPERATIONS Dust generation during skiphoist operation is difficult to control particularly at"the"loading and dumping stations. Many of the dust collection systems presently installed do not have adequate capture velocities and often during charging the frontend loader interferes with the dust capture mechanism. Compared with enclosed bucket elevators or pneumatic systems, skiphoists present a more difficult problem in terms of dust control but they do provide greater control during the formulation of the batch. If it is determined that a skiphoist operation is essential from a production standpoint then the path of travel of the hoist should be com pletely enclosed with braced and supported sheet metal with removeable panels for maintenance. The charge point should be exhaust ventilated using the existing dust collection system with replacement or reworking of the exhaust ducting. Capital Costs Skiphoist Enclosure Angle Iron Framing Dust Collection (3000 cfm) Ducting Materials and Equipment Cost Engineering Cost Total Capital Cost $ 6,468 2,000 24,000 9,000 $41,468 13,684 $55,152 d i i 3 1 I 1 1 B-48 Arthur DLitt^Ir 12c. BUCKET ELEVATOR Although bucket elevators are not generally considered to be sources of dust .generation jnany have leaking seals and missing panels. at a problem during material feed and discharge. With proper maintenance bucket elevators provide an efficient mechanism for the vertical transfer of materials. In some cases skiphoists will be replaced by bucket elevators which will also be installed as a loading mechanism for new storage facilities. For bucket elevators currently in place a typical reworking operation will include 40 hours of welding of broken seams and holes and installation of 1000 cfm of dust collection at the discharge. Rework Elevator Capital Costs Contractor welding Dust Collection (1000 cfm) Ducting Materials and Equipment Engineering Total Capital Cost Operating and Maintenance Costs General Dust Collection System Total Operating and Maintenance Costs $ 800 8,000 3,000 $11,800 3,894 $15,694 $o 1,600 $1,600 B-46 ] ] ] ] ] 1 2 1 Arthur D Ut J -V Jf fc i 12b. PNEUMATIC CONVEYOR SYSTEMS Pneumatic conveyor systems provide the most effective engineering control of dust generation during material handling. Tills systemmis, most--- useful over distances greater than 50 feet and for material of 100-mesh or smaller particle size. Although pneumatic systems are clean they are also expensive. Elbows, in particular, are subject to the abrasive action of the raw material. The pneumatic systems proposed in this section are for illustrative purposes only. The exact specifications will vary widely depending upon the specific plant layout. Pneumatic Transfer System 125 hp/30 tph Capital Cost Pneumatic Unloader Airconveyor with Piping Equipment and Materials Engineering Cost Total Capital Cost Operating and Maintenance Cost $ 80,000 30,000 $110,000 36.300 $146,300 14,630 I I i B-44 AnhurDLjtfi.il Capital Costs Disconnect and remove press Press Foundation Collection .Hopper Inclined Belt Conveyor 30' Bucket Elevator 8" x 12" Reposition and Reinstall Press Recrusher System Press Dust Collection Materials and Equipment Engineering Total Capital Costs Operating and Maintenance Costs General Dust Collection Total Operating and Maintenance Costs $ 6,000 25,000 -J.,000-5,400 18,000 10,000 6,000 56,000 $127,400 42,042 $169,442/p $ 3,000 12,800 $ 15,800 I I 3 I 1 f B-36 1 Arthur DUt4 Capital Costs Crossley Press Dust Collection (7000 cfm) Ducting Equipment and Material Engineering "'Total Capital Costs Operating and Maintenance Costs General Ventilation Total Operating and Ventilation Costs $300,000* 56,000 21% 000 $377,000 124,000 $501,000 $ 30,000 11,200 $ 41,200 This cost represents a completely outfitted press and lower priced models may be available. Also, other presses may be appropriate and individual designs should be selected based upon the needs of each specific operation. B-38 Arthur D Lilt! 36" Covered Belc Conveyor (suspended) Capital Cost Materials and Equipment Engineering Cost Total Capital Cost Operating and Maintenance Cost Covered Belt Conveyor (gallery) Capital Cost Materials and Equipment Engineering Cost Total Capital Cost Operating and Maintenance Cost 36'* Belt Conveyor Covers Capital Cost Materials and Equipment Engineering Cost Total Capital Cost . B-42 *$500/ft $167/ft 667/ft $ 50/ft SlOOO/ft 333/ft $1333/ft $ 100/ft $ 40/ft $ 13/ft $ 53/ft i i Arthur DLittfsr* 11. SACKING MACHINES Sacking of refractory materials is a dusty operation which is difficult to control with local exhaust ventilation. The typicali-machiria:5aaks"dustr'i` from cracked seams and shaft seals. During the filling operation dust leaks from the fill nozzle and excess material spills on the floor. On occasion sacks freak during the filling process and spill their contents on the floor. Local exhaust at the nozzle can control some of the dust at the nozzle but inadequate capture velocity limits its effectiveness. A large part of the control problem is the necessity for frequent maintenance and adjustment of the loading mechanism. This should be accompanied by frequent clean-up of spilled material. Capital Costs Rework Sacker * Dust Collection (2500 cfm ) Ducting $ 800 20,000 7,500 ] ] 3 Materials and Equipment Engineering Total Capital Costs Operating and Maintenance Costs General $26,300 9,300 $37,600 $ 80 ] ] I Ventilation Total Operating and Maintenance Costs * 2500 cfm/2 tube sacker B-40 4,000 $ 4,080* I I 3 -) Arthur D LittU a) Communal Svscem In this recycling system excess material pushed from the front of the press platen is manually loaded through a grated opening onto a trenched conveyor. This'cbnveyor collects material along the line of presses and discharges to a communal trenched conveyor which runs to a central bucket elevator. The excess material is elevated and recycled back to the mixer. For-analyticral purposes system costs such as trenching, lining and con veyors have been allocated on a per press basis. This procedure assumes that such a system would not be applicable to plants with limited pressing i capacities and that with larger operations the communal equipment might be xpanded. Capital Cost per Press Manual trenching and dressing $ 500 i i Gunnite lining of trench sides and bottom 1,000 Belt conveyor installations 30-foot 8" x 12" Bucket Elevator 1/4" Trench Cover Plates Press Enclosure Dust Collection 7,500 2,000 550 750 16,250 56,000 Engineering Total Capital Cost 27,720 Sill,720/press B-24 i l i l i I i Arthur D Li' Satching 1. Modify current use of weigh scale buckets and conveyors to include provision for Larry Car System using 2 cars with one held in reserve* $168,600 $ 5,500 Mixing 1. Enclose and exhaust 5 mixers feeding the press lines. Forming. 1. Rework 10 presses to install recycle system to collect spilled materials. Firing 1. Material substitute or more frequent replacement of setting sand. Finishing 1. Rework 2 grinding machines to reduce dust release during finishing. General Maintenance 1. Initial plant clean-up. Demolition 185,150 20,815 1,744,420 158,000 312,500 63,000 6,800 340,000 54,000 Electrical 1. Initial construction of electrical transformers. 4 20,000 753,923 A-61 Arthur Duttle COST OF COMPLIANCE (ccr. _H. RECURRING COStS A. Annual Operating & Maintenance D. OSHA Activities C. Material Substitution Total Recurring Cost Capital Annua 1 Operating Costs 439 7^5 , 137;TO`Q 3^2 ]_00 $889 315 A-63 Arthur DL-ttie I PLANT DESCRIPTION SILICA BRICK PLANT Raw Materials __ Iron oxide, calcium nitrate, lime, alumina, magnesia, bats, calcium oxide, titanium dioxide, gannister. Range of Products Silica brick and custom shapes. Production Flow Rav Materials Receipt and Storage Raw materials are received by truck and rail with unclassified materials stored in open stockpiles and purchased classified materials conveyed directly to storage. Crushing, Grinding and Screening Raw materials are fed to the crusher via a dump truck and the product is conveyed to intermediate storage facilities. Portions of the material from open stockpiles may be passed through a rotary kiln for drying purposes prior to crushing. Crushed materials are fed to grinding and screening operations to achieve further size reduction and are discharged into classified material storage bins. Oversized material is recycled to the grinder to maintain uniformity of product characteristics. A-65 Arthur D Little Irx. The discharge from che crusher is transferred via open conveyor to the primary storage areas where dust is generated during the filling of open storage bins. Additional sources of dust generation relate to the. secondary grinding and vibratory screening to further dassl'fy the raw materials. The screens are also operated with their covers removed which produces significant levels of dust. All intermediate material transfers are conducted via open conveyor including those shuttle conveyors employed to load individual storage bins. Storage bins have poor fitting covers and dust escapes from the bins during the filling operation. Dry materials are -drawn from storage and batched on a conveyor. Dust is generated at each of the conveyor drop points and problems are complicated because mixer access doors are left open during the feeding operation. The uncontrolled mixing operations are a continual source of dust generation until the mix achieves a water content of approximately 7Z by weight. The mixed materials are transferred via conveyor to the press storage bins. Dust is generated when Che wet materials drop from-* the conveyor, dry and become entrained. The press feeder bins discharge via gravity flow measured quantities of raw material to the press. Dust is generated both from the uncovered feeder bins and from the accumulations of excess feed material in the front and rear of the press. This material dries and becomes suspended as a result of drafts and physical disturbances associated with pedestrian and vehicular traffic. A-6 7 Arthur D Little.\rc COST OF COMPLIANCE SILICA BRICK Engineering Capital Raw Materials Receipt and Storage 1. Install covered storage and enclose FEL $360,000 2. Install 135 feet of covered and exhausted conveyor 54,000 3. Esdiaust 6 internal points 4. Enclose front-end loader Crushing 92,172 4,000 1. Rework crusher 58,810 2. Install 120 ft of suspended conveyor with 4 exhaust points 80,040 61,448 Drver None Grinding 1. Cover and exhaust 7 grinders 273,210 Storage 1. Cover and exhaust 7 bins 202,524 2. Cover and e^diaust batching conveyor 120 feet of 36 inch belt 61,448 Screening 1. Rework 6 units 228,180 2. Install solid screen floor 72,000 Batching /Mixing 1. Cover and esdiaust 420 feet of conveyor and 14 exhaust -points 215,068 2. Cover, and exhaust 9 wet can mixers. 273,210 A-69 Annual Operating Cost $-- 4,050 7,500 6,104 6,000 5,000 29,141 15,400 5,000 23,154 -- 17,500 29,141 Arthur D bule In SUMMARY COST OF COMPLIANCE SILICA BRICK PLANT I. FIRST YCAR COST A. Engineering Controls .1 Raw Materials Receipt 2. Crushing, Grinding Screening 3. Storage 4. Batching and Mixing 5. Forming, Firing, Finishing 6. Packaging 7. General Maintenance 8. Demolition Total Engineering Controls Equipment Annual Operating Coses $510,172 773,688 263,972 * 488,278 97,750 11,550 69,399 20,400 46,641 28,370 143,570 $2,280,430 $176,360 B. Plant Clean-Up 1. Initial 2. Annual C. OSHA Activities 27,000 40,000 79,040 D. Material Substitution Total First Year Cost $2,280,430 $427,400 A-71 Arthur D Lulu Irv. VOLUME II IMPACT OF AN OSHA REGULATION FOR CRYSTALLINE SILICA UPON THE REFRACTORIES INDUSTRY To THE REFRACTORIES INSTITUTE Pittsburgh, Pennsylvania 15222 Submitted by ARTHUR D. LITTLE, INC. Cambridge, Massachusetts 02140 C-80884 August 1, 1978 APPENDIX B COMPLIANCE COSTS B-l Arthur D Little Inc APPENDIX B TABLE OF CONTENTS COMPLIANCE COSTS UNIT COSTS COMPOSITE COSTS 1. Raw Material Storage 2. Primary Crushing 3. Grinding and Mixing Pans 4. Screening 5. Storage of Sired Materials a. Bln Enclosures b. Silo Storage 6. Tote Bins 7. Larry Cars 8. Automatic Sack Breaker 9. Press Modifications 10. Finish Grinding 11. Sacking Machines 12. Conveying a. Belt Conveyors b. Pneumatic Systems c. Bucket Elevators d. Skiphoist e. Screw Conveyors f. Drop Point Enclosures lage ` ' B-2 b-3 B-7 B-7 B-8 B-ll B-12 B-16 B-16 B-19 B-23 B-25 S-27 B-30 B-39 g_40 g-4i `1^4i B-44 B-46 B-48 B-50 5-51 B-l a Arthur D Little lx UNIT COSTS APPLICATION 36" BELT CONVEYORS Floor mounted Suspended Suspended with gallery 9" SCREW CONVEYORS First 10* with motor and drives Additional Use PNEUMATIC SYSTEMS - 10-30 TON/HR Equipment (pumps, compressor, piping controls) Maintenance Power BUCKET ELEVATORS (8" x 12") Equipment Head Boot Terminal ends Drive SCREENS Double deck 4 x 12, 20 tons/hr Scalper 150 ton/hr Exhaust COST $ 300/ft 500/ft 1000/ft $2500 100/ft 250/ft + 25% $10,0Q0-$15,000/Tons/hr $ ,20/Ton/hr $ .15/Ton/hr $550/ft $2500/ton 51.000 27.000 M % l LARRY CAR Dust tight car with local exhaust, bottom discharge PRESS MODIFICATIONS Vacuum system Recycle system New press DUST COLLECTION SYSTEM Collectors Ducts Operating Maintenance * VACUUM SYSTEMS FOR MAINTENANCE 50 hp, 5 ton/hr Piping CONVEYOR COVERS Duct replacement 8" 4" MATERIAL HANDLING VALUES Butterfly Rotary Good for 150* diameter coverage B-5 $50,000/car $ 33,250 $170,000 $365,000 $8/cfm $3/cfm $.10/1000 cfm/hr $l/cfm/yr $25,000 $ 5,000 i $30/ft $ 12/ft $ 800/valve $2300/valve a ___ Pv ! 1-.- COMPOSITE COSTS 1. RAW* MATERIAL STORAGE In most medium and large refractory plants raw material is delivered directly from mines and stored in open stockpiles prior-^=-- to crushing. Because of the coarseness of the material and the costs of material handling it is impractical to use a totally enclosed storage system. However, dust generation from the stockpiles does contribute to ambient dust concentrations and some control is warranted. In order to reduce dust levels, raw materials should be stored under cover on a 9-inch concrete pad 80' x 400*. fovable partitions within the storage building should be provided to prevent cross-contamination of materials. Capital Costs Reinforced Concrete Floor Structural Steel Corrugated Roofing Portable Dividers Materials and Equipment Engineering Cost Total Capital Cost $300,000 100,000 120,000 10.000 $530,000 53.000 $583,000 E-7 Arthur D Little Inc V 1) Control Booth The crusher operator should be provided with a dust-tight booth from which he can observe and control the crushing operation. Capital Costs Concrete Foundation $2,340 * Control Booth: Acoustical 5,000 Materials and Equipment 7,340 Engineering 1,650 Total Capital Cost $7,990 Operating and Maintenance Costs General $ 772 2) Hopper Vibrator For those cases where the flow of material in the crusher hopper becomes restricted, hopper vibrators should be installed. Manual operations are not only unsafe but also lead to excessive exposures to silica dust. The feeder hopper should be modified to increase the angle of repose of the hopper sides. Capital Costs Modifications to Feeder Hopper $ 1,000 Installation of Hopper Vibrators Acoustical Control Booth 1,700 5,000 \ Concrete Foundation 2t340 Materials and Equipment $10,040 Engineering Total Capital Cost 1,650 $11,690 B-9 Arthur Dbttlelnc 3. GRINDING AND MIXING PANS Grinding and mixing_.pans are found in several sizes with- various71?--- binacions and conditions of enclosures, seals, access doors and ventila tion systems. In general, they are in poor repair and even enclosed systems have numerous holes and broken seams from which dust escapes. Costs for dust control will vary depending upon the availability of pre existing dust collection capacity and the degree of effort required to make the pan dust-tight. Production interruptions will occur when the mixing pans are reworked. Capital Costs Full Pan Enclosure * Dust Collection System (2500 cfm ) Door Gasket and Interlock Materials and Equipment Engineering Total Capital Cost Operating and Maintenance Costs General Dust Collection Total Operating and Maintenance Costs $ 1,500 27,500 130 29,130 9,900 $39,030 $ 163 -A0pQ $ 4,163 Assumes no exhaust provided. If exhaust is provided it should be incremented to 2500 cfm. B-ll Arthur D Little. !nc The most effective control involves fully covered and exhausted screens with individual screens separated from the general plant and each other through a dust-proof enclosure. The enclosure must, however, be.-.afr=asple~ -- size to permit full service of the screening unit, including adequate room to change the screens. Capital Costs (Per Screen) Screen Enclosure Dust Collection (2000 cfm) Ducting Screen Cover Equipment and Materials Engineering Costs Total Capital Costs $ 6,344 16,000 6,000 250 $28,594 * 9,436 $38;030 Operating and Maintenance Costs General Ventilation System Total Operating and Maintaining Costs 659 3.200 $ 3,859 5-13 Arthur D Utile ir>c B. Flat Peck Screen - 20 Tons/Hr Capital Costs Double Deck Screen Dust Collect "(2000 cfo) Equipment and Materials Engineering Total Capital Costs Operating and Maintenance Costs General Ventilation System Total Operating and Maintenance Costs $50,000 22,000 $72,000 24,000 $96,000 $ 5,000 3,200 $ 8,200 E-i' Arthur D bale Inc Covered Screw Conveyor Covered Belt Conveyor Weigh Plate .. Materials and Equipment Engineering Cost Total Capital Cost Operating and Maintenance Cost* General Dust Collection Total Operating and Maintenance Cost Steel Bin Enclosures (conveyor transfer) Capital Cost Dust Collection (1000 cfm) Ducting Bin Enclosure Covered Screw Conveyor Covered Belt Conveyor Materials and Equipment Engineering Cost Total Capital Cost 2,000 4,080 500 f $21,754 7,178 $28,932 $ 600 160Q $ 2,200 $ 8,000 3,000 1,000 2,000 4,080 $18,080 4,151 $22,231 B-i 7 5b. SILO STORAGE The storage of classified materials in open bins and stockpiles leads to dust generation and--exposures during material handling hperatibifsi' This ~~ is also a source of contamination for other plant areas because of the tendency for airborne dust to circulate. The preferred system includes an enclosed silo with a covered conveyor or bucket elevator feed and an en closed discharge to the grinding and screening areas. Steel silos are supported by structural steel members mounted on individually reinforced concrete footings. Additional bracing steel trusses may be necessary to ensure adequate latitudinal support. The dimensions and capacity of the silos will vary depending upon the amounts and varieties of materials to be stored. As a general rule a storage silo for classified material should not exceed 6 feet in diameter. In situations where raw material is wet provisions should be made for rotary drying before storage Silo Costs Bulk storage of unclassified material is to be maintained in -IS" feet '* diameter silos with capital costs of $175/ton for capacities of 350-500 tons. For silos of 50-350 tons capacity, the cost is $2507ton. Classi fied materials will be stored in silos of up to 50 ton capacity but , restricted to 6 feet diameter. Capital costs are $400 per ton of capacity. In all cases, foundation costs are 25% of silo costs. B-19 Arthur DLiuie.lrc  Silo Loading Depending upon the plant layout and the material being handled, a silo may be loaded by a covered inclined conveyor, by an enclosed buckem*-., elevator, by a combination of conveyors and bucket elevators or by a pneumatic system. 36" Covered Conveyor-floor mounted Engineering Cost Operating and Maintenance Cost 36" Covered Conveyor - suspended Engineering Cost Operating and Maintenance Cost 36" Gallery Covered Conveyor Engineering Cost Operating and Maintenance Cost 8" x 12" Enclosed Bucket Elevator Engineering Cost Operating and Maintenance Cost' $300/ft 100/ft $400/ft $ 30/ft $500/ft 167/ft $667/ft $ 50/ft $1000/ft 333/ft $1,333/i:t $ 100/ft $ 550/ft 180/ft $ 730/ft $ 55/ft E-21 Arthur D Little inc 6. TOTE BINS Many batching systems utilize portable tote bins to collect materials from several sources including silos, bins and bag breaking stations. Tote bins can have open tops or narrow mouths and may discharge from the bottom or tip into the receptacle (e.g., skiphoist or mixer). In some cases the entire tote bin is loaded into the skiphoist and elevated to the mixing location. Although considerable variety exists in tote bin material handling systems, most generate excessive amounts of dust. Enclosed and ventilated systems are recommended for all material handling operations. The composite cost presented below are for a ventilated station where four tote bins (mounted on a weigh station) discharge material via covered screw conveyors to a weigh hopper which in turn is used to feed known amounts of material to a mixer. Capital Cost Tote Bins Weigh Station Dust Collection (1000 cfm) Ducting Equipment and Materials Engineering Cost Total Capital Cost $ 4,000 30,000 8,000 3,000 $45,000 14,850 $59,850 E-23 Arthur D Little Inc. 7. LARRY CARS Batch handling of sized raw materials from storage bins often requires use of a ventilated larry car which is manually propelled or powered on rails below the bin feeders. Batches are drawn by weight or volume and transferred to mixers. Although the cars are usually ventilated, the drop point from the bin feeder to the car is open and the exhaust capacity is not sufficient to control all of the dust emissions. In some cases it may be possible to retrofit the present larry cars to provide for a dust-tight connection between the valve in the hopper discharge and the inlet to the larry car. There is some concern regarding the efficacy of this retrofit operation and in many situations the only alternative is to purchase new larry cars which are designed specifically to insure that dust-tight and ventilated connections are maintained during the batching operation. Capital Costs Retrofit of Existing Car Ventilation (1000 cfm) Ducting Equipment and Material Engineering Total Capital Costs Operating and Maintenance Costs General Ventilation Total Operating and Maintenance Costs B-25 $ 3,000 8,000 3,000 $14,000 4,620 $18,620 $ 300 $ 1,600 $ 1,900 8. automatic sack breaking stations Whenever sack breaking occurs there is considerable material spillage and dust generation. Ventilated sack breaking stations can limit the amount of dust generation, however, the capture velocities are insufficient to adequately control the dust. Even the most modem manual stations can cause silica exposures in excess of the present standard. An alternative method for handling sacked material would include the installation of ventilated sack breaking machines with enclosed feed to a conveying system or tote bin. These devices have not been employed within the refractories industry because of problems associated with product contamination. An additional advantage of the automatic system is that the optional bag compactor will eliminate dust generated from handling empty bags. Sack breaking stations should be utilized for those'situations where there is a limited amount of variation in the product-mix. For those operations where there would be a continuous run of a single sacked material (equivalent to 15-25 tons) it may be practical to install a sack breaking machine. The large number of single product bags which would be continuously broken can justify the intallation of the automatic sack breaking machine. It should be mentioned that costs are comparable for the automatic sack breaking machine and the traditional sack breaking station. However, when there are a large number of different sacked products being batched. B-27 Arthur D Little Inc Capital Costs Bag Breaking Station Fabrication Compactor Ventilation (1500 cfm) Ducting Hopper Discharge -Conveyor-Loader Equipment and Material Engineering Total Capital Costs Operating and Maintenance Costs General Ventilation Total Operating and Maintenance Costs l I % i $ 5,000 9,000 12,000^ 4,500 1,000 3,000 34,500 11,385 $45,885 $ 1,400 2,100 $ 3,500 M t 5-29 Arthur D Little Inc t? * Portable Vacuum System (50 hp) Capital Cost Engineering Total Capital Cost Operating and Maintenance Cost $25,000 8,250 $33,250 12,500* "< , 2) Press Enclosure * In some cases a system currently is in place to collect and dispose/recycle material spillage, but there may still be a dust problem. Where spilled material becomes rapidly airborne it will be preferable to enclose the press except for the working mouth and platen. Because of the necessity to clean and maintain the press, the enclosure must be designed with easily removeable panels. The structure is constructed of medium gauge sheet metal attached to framing with all seams gasketed in a dust-tight manner. Capital Cost Per Press Top 338 ft2 @ $10 Sides (2) 676 ft2 <3 $10 Rear Panel 338 ft2 <? $10 Partial Front Far.ei 273 t`t d $10 Capital Cost Engineering Total Capital Ccst Operating and Maintenance $ 3,380 6,760 3,380 2,730 $16,250 5,363 $21,613/press 2,163/press