ENCYCLOPEDIA OF ENVIRONMENTAL SCIENCE AND ENGINEERING - MANAGEMENT OF SOLID WASTE pot

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ENCYCLOPEDIA OF ENVIRONMENTAL SCIENCE AND ENGINEERING - MANAGEMENT OF SOLID WASTE pot

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642 MANAGEMENT OF SOLID WASTE INTEGRATED WASTE MANAGEMENT The most recent comprehensive document produced by the federal government characterizes the materials commonly referred to as “municipal solid waste” (“MSW”) as follows: “ . residential solid waste, with some contribution from commercial, institutional and industrial sources. In some areas, nonresidential wastes are managed separately, largely because industrial and some commercial sources produce relatively uniform waste in large quantities, which makes them more suitable for alternate disposal techniques or recycling. Hazardous wastes, as defined by Federal and State regulation, generally are managed outside the munici- pal solid waste stream. Exceptions are household hazardous wastes and hazardous wastes generated in very small quan- tities, which are often placed in the municipal solid waste stream by the generator.” 1 One of the most significant developments in municipal solid waste is the growing acceptance by citizens, all levels of government, and industries of a new overall philosophy concerning the management options available to address the problem of increased waste generation in the face of ever- decreasing land disposal sites. This philosophy is commonly known as “integrated waste management” and involves the reliance upon a hierarchy of options from most desirable to least desirable. The options are as follows: Source reduction, limitation of the amount and/or toxicity of waste produced Recycling, reuse of materials Incineration, thermal reduction Sanitary landfill, land disposal While this hierarchy is little more than a common sense approach to municipal solid waste problems and the unit operations represented are not new, emphasis on the source reduction and recycling options as preferred represents a pro- found shift in attitudes toward municipal waste management. The traditional perspective that generators could produce dis- cards without limit and depend on technological approaches to mitigate such wastes and any associated effects of treat- ment is no longer acceptable. This approach is not unique to the solid waste area but is a part of federal and state “pol- lution prevention” strategies, which emphasize avoidance of all types of pollution as preferable to “end of pipe” and other traditional methods of environmental regulation. LEGISLATION In 1984, amendments were made to the Resource Conservation and Recovery Act of 1976 (“RCRA”), the existing federal legislation covering solid waste management. Although the majority of these amendments were concerned with the regulation of hazardous waste as were the original RCRA mandates, some changes and additions were made to those provisions which were directed at nonhazardous waste. The U.S. Environmental Protection Agency (“EPA”) was directed to determine whether the existing criteria for land disposal of waste previously promulgated pursuant to Sections 1008(a) and 4004 of RCRA are adequate to protect human health and the environment from groundwater con- tamination and whether additional authorities are needed to enforce them. In addition, EPA must revise the criteria for those facilities which may receive hazardous household or small quantity generator waste. Furthermore, States were given three years to develop a program to ensure that munici- pal facilities met the existing criteria and the revised crite- ria when they are promulgated. Although enforcement is still largely a state matter, EPA is empowered, though not required, to enforce the criteria if states fail to comply with their obligations. As of this writing, revised criteria have been proposed but not yet adopted. 2 Perhaps the most significant aspects of the federal law and its implementation involve initiatives with legislative roots in the original RCRA legislation which had historically received less attention than the Act’s mandate to establish a hazardous waste management regulatory system. EPA has begun pursuing a number of activities such as conservation of virgin materials through guidelines establishing revised product specifications and similar initiatives. State legislation has also witnessed a marked shift toward more conservation-oriented management schemes as well as stricter standards for processing and land disposal facilities. For example, at least twenty-four states have laws mandating the use of recovered materials in procurement processes. As of this writing, nine states had legislation requiring deposits on beverage containers and four states had mandatory recy- cling laws covering a wide range of materials. The scope of these new legislative initiatives and the myriad of options and alternatives they entail is beyond the purview of this analysis. What is apparent, however, is that source reduction and recycling represent an important part of modern waste management systems. C013_002_r03.indd 642C013_002_r03.indd 642 11/18/2005 2:27:17 PM11/18/2005 2:27:17 PM © 2006 by Taylor & Francis Group, LLC MANAGEMENT OF SOLID WASTE 643 INTRODUCTION Any discussion of solid waste neatly divides into three categories: 1) Source and composition, 2) Collection, 3) Disposal (or, hopefully, reuse). Another natural division, resulting in part from the current reg- ulatory states, is between hazardous and nonhazardous wastes. This section will deal primarily with nonhazardous wastes; specifically, with their source and composition and disposal. However, a brief discussion of hazardous wastes is included because of their importance in understanding the management of urban waste. More detailed discussion of hazardous waste is found in another section. The important problem of collec- tion is also left to a special section on that subject. Solid waste used to be considered any solid matter which was discarded as no longer being useful in the economy. During the last decade, this definition has been considerably broadened. For regulatory, and usually disposal purposes, solid waste is now defined as “any garbage or refuse, sludge from a waste treatment plant, water supply treatment plant, or air pollution control facility, and other discarded mate- rial, including solid, liquid, semi-solid, or contained gaseous material resulting from industrial, commercial, mining, and agricultural operations, and from community activities, but does not include solid or dissolved materials in domestic sewage, or solid or dissolved materials in irrigation return flows or industrial discharges which are point sources.” 3 This definition is important because it indicates that all matter which is disposed of onto the land in any form is considered “solid waste.” In addition that material which causes or sig- nificantly contributes to an increase in mortality or serious illness or poses a substantial hazard to human health or the environment, is considered a “hazardous waste.” Hazardous wastes have been further defined by rulemaking to a limited set of materials and criteria such as toxicity, flammability, reactivity, or corrosivity. 4 The handling of hazardous waste requires special care and special permitting. Contrary to the management of normal refuse or solid waste, the generators, transporters, and disposers of hazardous wastes must meet stringent federal and state criteria and have considerable potential liability exposure. The disposers of solid waste which is not hazardous must meet state criteria that are not nearly as stringent as those for hazardous materials. Thus, while hazardous material in the past has been often disposed of along with all other refuse, today this is no longer the case. Industrial waste generators segregate their hazardous from their industrial waste so as to minimize their problems. Solid wastes are one of the three major interacting waste vectors; the others are air and water pollutants. Solid wastes, if improperly handled, can be a source of land, air and water pollution. They are, also, at this writing, one of the most vol- atile public issues and a problem which is presenting many communities with significant institutional challenges. Significant progress has been made in regulating the dis- posal of solid waste over the last decade. Open dumps which presented aesthetic as well as environmental challenges are for the most part closed. Regulations are in place for managing solid wastes in an acceptable manner. However, dumping into the ocean, which can create “dead” zones, hopefully will be eliminated. Nor have we eliminated the potential problems of leachate from landfills. Perhaps the most significant problem is the one of locating new landfills or substituting resource recov- ery, reuse and recycling capacity for landfill disposal. The technologies are available, but the economics still favor land disposal. In the early ’70s there was great hope for massive resource recovery and recycle projects. Some of those, dis- cussed later in this section, have not come to fruition because of economic and institutional barriers. Others have succeeded but the technology has not been spread, primarily because of economic barriers. Individual and community action to reduce the amount of wastes generated and collected has, in many areas of the country, been successful. For example, solid waste contains significant amounts of valuable material; 40% to 50% of urban waste is paper and, if recycled, can replace virgin stock equivalent to about 9 trees per person per year. In addi- tion, the community and thus the taxpayer also saves in terms of lower collection and disposal costs. However, this is still of limited application because it is usually limited to newspa- pers, aluminum cans and perhaps glass. Both technology and institutional methodologies for recycling solid waste are still in their infancy and must gain momentum if we are to meet the challenge of solid waste management in the years to come. REGULATION OF SOLID WASTE MANAGEMENT Regulation of solid waste management has been scattered. The federal government, contrary to its prior policies in air and water, did not take a strong posture in solid waste management. It left regulatory initiative to the states and localities. These dealt with the solid waste management primarily through the licensing of collectors, through the “Utility Commissions” and adding to zoning ordinances regarding local landfills. Public health regulations also played a role with respect to reduction of rodents and pests at landfills. Air emissions from incinerators were regulated as were wastewater discharges. In the last several years a number of states have enacted and implemented legislation to regulate landfills. Probably the earliest and still among the most comprehensive is the regu- latory effort of the State of California which has classified landfills which respect to underlying geological conditions in terms of what a landfill can and cannot accept. A comprehensive solid waste law at the federal level was passed in 1976 as the “Resource Conservation and Recovery Act of 1976.” 5 This act provides for federal assis- tance to states and regions developing and encouraging environmental sound disposal of solid waste and the maxi- mum utilization of resources. It calls for state and regional plans and for federal assistance to develop these plans. It requires that each plan shall prohibit the establishment of open dumps and provides for the upgrading of open C013_002_r03.indd 643C013_002_r03.indd 643 11/18/2005 2:27:17 PM11/18/2005 2:27:17 PM © 2006 by Taylor & Francis Group, LLC 644 MANAGEMENT OF SOLID WASTE dumps that are currently in use. It also requires that crite- ria for sanitary landfills be established. However, it leaves enforcement to the states. At the same time, the Act under Subtitle C provides for federal regulation of the manage- ment of Hazardous Wastes. Many of these regulations have been issued but the critical ones covering treatment, stor- age and disposal facilities are still under review. SOURCES OF WASTE Solid waste differs from air and water pollutants in that it comes in discrete quanta and is very heterogeneous in nature. Both composition and rate vary significantly from day to day and from season to season as well as from otherwise similar sources. The solid waste production in the United States is in excess of four billion tons/year and was expected to increase to five billion tons by 1980. 6 Table 1 breaks this down for the year 1967 by major source. However, waste generation appears to have stabilized despite increased loads from air and water pol- lution control facilities. How long this will last remains to be seen, if and when significant conversions to “coal as fuel” and more stringent air and water pollution control take place. Urban Waste Urban waste collected is between 4 and 8 lbs per person per day, with typical values lying between 4.5 and 5.5 lbs per day. This differs from the amount generated because of self and private disposal. The major wastes included in this category are tabulated in Table 2, which includes a summary of disposal trends. One should be careful in the terminology because often domestic and municipal are used interchangeably to indicate the total refuse picked up from residential (domestic), institu- tional, small business and light industrial sources. Some further definition of terms may be useful at this point. In general usage many of the terms have been used interchangeably. However, an effort to standardize the ter- minology was made by the Institute for Solid Waste of the American Public Works Association and the Office of Solid Waste Management of the Environmental Protection Agency. 7 The standard usage of terms detailed by these groups is summarized here: Refuse All solid waste matter. Garbage The animal and vegetable waste resulting from the preparation of food. Rubbish The waste from homes, small businesses, and so on excluding garbage. Trash Used equivalent to rubbish. Litter Street refuse. Industrial Waste Specialized refuse from manufactur- ing plants, and usually excludes rubbish. Domestic waste composition will vary seasonally, as well as with locale and economic status. Typical analyses for domes- tic plus municipal refuse are shown in Table 3. As can be seen in a comparison of the data, the composition has not changed drastically with time except for a significant reduc- tion in ash because of the change from coal as a home heat- ing fuel. Location variations noted are as great or greater. A study of seasonal variations made in 1939 for New York City also showed greater variations: the ranges were garbage, 44 to 3.5%; and metal, 11.6 to 3.1%. 8 Base data have been difficult to obtain because of the many variabilities in the base. The most significant variables include the economic level of the area, the ratio of commercial to residential property, the type of commercial establishments and the housing density and age. The entire picture on obtaining accurate data on urban and/or domestic refuse is further complicated by the sampling problem. A discussion of this problem is beyond the scope of this work; the reader is referred to some basic work in this area by Carruth. 9 An excellent review of sampling and testing has been prepared by the Institute of Solid Wastes. 10 Further work is being done in this area by ASTM’s D-34 Committee. The ultimate chemical composition of municipal refuse has been examined by a number of investigators. Table 4 gives the range of values to be expected. Recently 0.3 to 0.5% chloride has been found in refuse independent of the presence of poly- vinyl chloride; this is due to the presence of salt primarily. 11 Density of municipal refuse varies with the load applied to it. Typically household refuse has a density of 350–400 pounds per cubic yard. Transfer stations and/or landfill operations can compact it to between 500 and 800 lbs per cubic yard depend- ing upon the material and conditions. The effect of compres- sion on density for the Chandler, Arizona refuse is shown in Figure 1. High pressure compaction (see Compaction) can increase the density to 1200 to 1400 lbs per cubic yard. Industrial Wastes Industrial wastes amount to about 115 million tons annually. They include any discarded solid materials resulting from an TABLE 1 Major sources of waste matter United States 1967 5 Source Solids generated lab/cap/day Million tons/yr Urban Domestic 3.5 128 Municipal 1.2 44 Commercial 2.3 84 Sub total 7.0 256 Industrial 3.0 110 Agricultural Vegetation 15.0 552 Animal 43.0 1563 Sub total 58.0 2115 Mineral 30.8 1126 Federal 1.2 43 Total 100.0 3650 C013_002_r03.indd 644C013_002_r03.indd 644 11/18/2005 2:27:17 PM11/18/2005 2:27:17 PM © 2006 by Taylor & Francis Group, LLC MANAGEMENT OF SOLID WASTE 645 industrial operation or establishment with the exception of dissolved or suspended solids in domestic or industrial waste waters. The composition and quantity of industrial solid wastes vary significantly from location to location, as well TABLE 2 Composition of wastes from urban sources 6 Urban sources Waste Composition Disposal, present Domestic Garbage Wastes from preparation, handling and sale of food Rubbish, trash Paper, wool, excelsior, rags, yard trimmings, metals, dirt, glass, crockery, minerals Landfill Ashes Residue from fuel and combustion of solid wastes Incineration Bulky wastes Furniture, appliances, rubber tires Dumping Commercial Garbage Same as domestic Landfill Institutional Rubbish, trash Same as domestic Incineration Ashes Same as domestic Demolition wastes, urban renewal, expressway Lumber, pipes, brick masonry, asphaltic material and other construction materials Dumping Landfill Construction wastes Scrap lumber, pipe, concrete, other construction materials Dumping Landfill Open burning Special wastes Hazardous solids and semiliquids, explosives, pathological wastes, radioactive wastes Burial, incineration Special Municipal streets, incinerators, sewage treatment plants, septic tanks Street refuse Dead animals Abandoned vehicles Fly ash, incinerator residue, boiler slag Sewage treatment residue Sweepings, dirt, leaves Cats, dogs, horses, etc. Unwanted cars and trucks Boiler house cinders, metal scarps, shavings, minerals Solids and sludge Fill Bury or incinerate Reclaim Landfill or dump Landfill — 0 20 40 60 80 100 100 300 500 700 900 1100 1300 DENSITY, LBS/CUBIC YARD APPLIED LOAD, LBS./SQ. IN. FIGURE 1 Refuse density. Household refuse, Chandler, Ariz., 1954. Credit: APWA, Municipal Refuse Disposal; 1966. as between industries and within a given industry. Table 5 lists the type of wastes to be expected from the various SIC Industrial Groups. A large fraction of the wastes are generally common to most industries and are listed on Table 6. Data on the amounts of waste generated by or collected from various industries is very limited. Industry, quite natu- rally, has considered this type of data confidential in that it often reveals significant process and economic information. Average data, even if available, are of limited value because wide variations can result from process differences, process efficiencies and direct recycle, as shown in a study based on detailed interviews. The results of this study giving total waste by industry are summarized in Table 7. Industry waste pro- duction on a unit per employee basis vary widely and are sum- marized for large and small companies in Tables 8 and 9. Increased efficiency as well as new uses for present indus- trial waste streams will alter both the quantity and composition of the material for disposal in the next decade. For example, saw mill waste is being reprocessed into composition board and this utilization could essentially eliminate this waste stream. Only limited projections can and have been made and these show only a reduction in saw mill wastes. 12 Conversely, enforcement of air pollution statutes will increase the amount of potential solid wastes significantly. Greater purification of industrial wastewater will also affect the solid waste load. Agricultural Wastes Agricultural wastes are principally organic as indicated in Table 10. The exceptions are chemicals used in various facets of farming such as pesticides, containers, and small amounts C013_002_r03.indd 645C013_002_r03.indd 645 11/18/2005 2:27:18 PM11/18/2005 2:27:18 PM © 2006 by Taylor & Francis Group, LLC 646 MANAGEMENT OF SOLID WASTE TABLE 3 Urban refuse, typical compositions Source Hempstead, NY Hempstead, NY Chicago 56–58 Chandler, Arizona St Clara County, Calif. Berkeley, California Del. Co.Pa. time 64 6/66 2.67 average 1953 1967 1952 1967 1980 Material Paper and paper prod. 56.01 53.5 32.71 53.33 56.5 42.7 50 69.0 c 69.7 c 38 compostable material Wood 2.82 — 1.22 1.46 — 2.3 2 — — — Grass, leaves, etc. 7.56 9.14 33.33 0.26 9.6 1.3 9 — — 8 Rubber 0.42 0.38 — — — 0.7 1 — — 12 Plastic 3.50 0.76 2.45 3.45 — 0.4 1 — 1.9 — Oil, paint 0.84 0.76 — — — — — — — — Dirt 2.52 2.29 aa —— ———— Rags 0.84 0.76 3.00 2.24 1.9 2 1.5 1.1 4 Miscellaneous 0.52 0.38 — — — — 8 7.6 7.4 6 Rubbish — — — — — — — — — — Garbage 9.24 6.11 9.58 16.70 4.8 21.8 12 dd 9 Fat — 2.29 — — — 11.3 — — — — Metal 7.53 6.85 7.96 10.60 14.8 b 9.8 8 10.6 8.7 13 Glass, ceramics 8.50 7.73 9.75 11.87 7.8 7 11.4 11.3 10 Ash — — — — 18.7 — — — — — Reference (7) (8) (9) (9) (10) (11) (12) (13) (13) — a Included in glass and leads. b Glass averaged 6.4% range 3.5–9.3%. c Includes garbage. d Included in compostable material. C013_002_r03.indd 646C013_002_r03.indd 646 11/18/2005 2:27:18 PM11/18/2005 2:27:18 PM © 2006 by Taylor & Francis Group, LLC MANAGEMENT OF SOLID WASTE 647 of miscellaneous waste matter resulting from maintenance and general housekeeping. Most crop waste is either plowed back into the soil or composted. Some open burning takes place. In some special cases such as bagasse (sugar cane stalks) industries have been established to utilize the waste material. Essentially none of this material finds it way into the usual disposal facilities. Animal wastes pose a different problem because much is produced in very concentrated areas such as feed lots or poultry farms. The disposal of these wastes is posing a greater problem than crop waste, but may be more easily solved because it is concentrated and therefore susceptible to processing without collection. Average waste yields for a variety of domestic animals are summarized on Table 11. Mineral Wastes Mineral wastes including solids generated in mining, milling and processing industries are expected to reach between two and four billion tons per year in 1990. In 1965 this waste amounted to 1.4 billion tons, as summarized in Table 12. Hazardous Wastes Hazardous wastes as defined by the federal government and in many cases similarly by the states, must be receiving spe- cial handling. These wastes generally include materials that are injurious to human health, toxic, can cause irreversible environ- mental damage, such as high concentrations of pesticides, are corrosive, reactive (form toxic gases), or highly inflammable. These wastes are defined in Federal Regulations (40CFR261). They require special management from generation through treatment and disposal as defined again by Federal Regulations. A detailed discussion of Hazardous Waste Management is cov- ered in a section on Hazardous Waste. Processing Methods A variety of processing methods, as summarized in Table 13, are available at present for handling solid wastes. Most have been in use in some modification for at least the last 50 years. The choice of processing method will depend not only on the type of waste but also on location, sources, quantity of waste, method of collection, public opinion, and ultimately economics. Solid waste management was a 4.5 billion dollar indus- try in 1968. It is only in recent years that the public has begun to worry about disposal of solids. Prior to that it was “out-of-sight, out-of-mind.” With ever growing amounts of solid waste as detailed in the discussion on sources, and con- cerns about pollution of ground and drinking water as well as release of hazardous materials, public pressure is becom- ing a major factor in any decision on waste management. The major disposal methods in use are landfill and incin- eration. Of potential interest in the United States are high pres- sure compaction and reclamation by recycling. Recycling is being used, but requires solution of institutional and techno- logical barriers before becoming a major factor. Compaction is utilized in at least one major facility in the Meadowlands in New Jersey. Composting is practiced in Europe, but also has not been successfully applied in the United States although it does have potential. There are new processes and techniques appearing for waste disposal and for the first time an organized research and development effort was mounted in the early ’70s to look at solid waste disposal; it has slowed down but there is ample opportunity for further progress. Disposal methods could be discussed from the point of view of source: a brief summary of the most used meth- ods for a variety of sources may be found in Table 14. This discussion will instead focus on the disposal methods most commonly in use today, landfill and incineration, followed by discussion of compaction, composting, and some of the newer disposal techniques. The oldest method of disposal is dumping either on land or sea. Here dumping in distinguished from Sanitary Landfill (see below). Dumping costs between $6 and $10 per ton and has been used for all waste materials. It is totally unsatisfac- tory for putrescible materials such as food wastes and unsatis- factory from a public health as well as aesthetic and land use viewpoint, even for inert material such as demolition waste. Open burning is often used for demolition waste, tree branches and stumps, and similar items; it is unacceptable because of the air pollution it creates. Neither dumping nor open burning have a place in the modern waste disposal scheme and are illegal. Sanitary Landfi ll Landfill is the most widely used method of waste disposal. There are 8900 authorized sites (about half publicly oper- ated) used by the 6300 communities surveyed in 1968. 14 There appeared to be an equal number of unauthorized dumps. Unfor- tunately only 6% of the sites were considered to be “truly” sanitary. The remainder fell either into Category B or C on the US Public Health Service Classification Scale, summarized in TABLE 4 Municipal refuse B ultimate chemical analysis Constituents % by weight (as received) Proximate Analysis — Moisture 15–35 Volatile matter 50–65 Fixed carbon 3–9 Noncombustibles 15–25 Ultimate analysis — Moisture 15–35 Carbon 15–30 Oxygen 12–24 Hydrogen 2–5 Nitrogen 0.2–1.0 Sulfur 0.02–0.1 Chloride 0.3–0.5 (16) Noncombustibles 15–25 Heating values, Gross 3000–6000 Btu/1b C013_002_r03.indd 647C013_002_r03.indd 647 11/18/2005 2:27:18 PM11/18/2005 2:27:18 PM © 2006 by Taylor & Francis Group, LLC 648 MANAGEMENT OF SOLID WASTE TABLE 5 Sources and types of industrial wastes SIC group classification Waste generating process Expected specific wastes Plumbing, heating, air conditioning Special trade contractors Manufacture and installation in homes, buildings, and factories Scrap metal from piping and duct work; rubber, paper, and insulating materials, miscellaneous construction and demolition debris Ordnance and accessories Manufacturing and assembling Metals, plastic, rubber, paper, wood, cloth, and chemical residues Food and kindred products Processing, packaging, and shipping Meats, fats, oils, bones, offal, vegetables, nuts and shells, and cereals Textile mill products Weaving, processing, dyeing, and shipping Cloth and fiber residues Apparel and other finished products Cutting, sewing, sizing, and pressing Cloth and fibers, metals, plastics, and rubber Lumber and wood products Sawmills, mill work plants, wooden container, miscellaneous wood products, manufacturing Scrap wood, shavings, sawdust; in some instances metals, plastics, fibers, glues, sealers, paints, and solvents Furniture, wood Manufacture of household and office furniture, partitions, office and store fixtures, and mattresses Those listed under Code 24, and in addition cloth and padding residues Furniture, metal Manufacture of household and office furniture, lockers, bedsprings, and frames Metals, plastics, resins, glass, wood, rubber, adhesives, cloth, and paper Paper and allied products Paper manufacture, conversion of paper and paperboard, manufacture of paperboard boxes and containers Paper and fiber residues, chemicals, paper coatings and fillers, inks, glues, and fasteners Printing and publishing Newspaper publishing, printing, lithography, engraving, and bookbinding Paper, newsprint, cardboard, metals, chemicals, cloth, inks, and glues Chemicals and related products Manufacture and preparation of organic chemicals (ranges from drugs and soups to paints and varnishes, and explosives) Organic and inorganic chemicals, metals, plastics, rubber, glass, oils, paints, solvents and pigments Petroleum refining and related industries Manufacture of paving and roofing materials Asphalt and tars, felts, asbestos, paper, cloth, and fiber Rubber and miscellaneous plastic products Manufacture of fabricated rubber and plastic products Scrap rubber and plastics, lampblack, curing compounds, and dyes Leather and leather products Leather tanning and finishing: manufacture of leather belting and packing Scrap leather, thread, dyes, oils, processing and curing compounds Electrical Manufacture of electric equipment, appliances, and communication apparatus, machining, drawing, forming, welding, stamping, winding, painting, plating, baking, and firing operations Metal scrap, carbon, glass, exotic metals, rubber, plastics, resins, fibers, cloth residues Transportation equipment Manufacture of motor vehicles, truck and bus bodies, motor vehicle parts and accessories, aircraft and parts, ship and boat building and repairing, motorcycles and bicycles and parts, etc. Metal scrap, glass, fiber, wood, rubber, plastics, cloth, paints, solvents, petroleum products Professional, scientific controlling instruments Manufacture of engineering, laboratory, and research instruments and associated equipment Metals, plastics, resins, glass, wood, rubber, fibers, and abrasives Miscellaneous manufacturing Manufacture of jewelry, silverware, plated ware, toys, amusement, sporting and athletic goods, costume novelties, buttons, brooms, brushes, signs, and advertising displays Metals, glass, plastics, resins, leather, rubber, composition, bone, cloth, straw, adhesives, paints, solvent Stone, clay, and glass products Manufacture of flat glass, fabrication or forming of glass: manufacturer of concrete, gypsum, and plaster products; forming and processing of stone and stone products, abrasives, asbestos,and miscellaneous nonmineral products. Glass, cement, clay, ceramics, gypsum, asbestos, stone, paper, and abrasives Primary metal industries Melting, casting, forging, drawing, rolling, forming, and extruding operations Ferrous and nonferrous metals scrap, slag, cores, patterns, bonding agents Fabricated metal products Manufacture of metal cans, hand tools, general hardware, nonelectric heating apparatus, plumbing fixtures, fabricated structural products, wire, farm machinery and equipment, coating and engraving of metal Metals, ceramics, sand, slag, scale, coatings, solvents, lubricants, pickling liquors Machinery (except electrical) Manufacture of equipment for construction, mining, elevators, moving stairways, conveyors, industrial trucks, trailers, stackers, machine tools, etc. Slag, sand, cores, metal scrap, wood, plastics, resins, rubber, cloth, paint solvents, petroleum products C013_002_r03.indd 648C013_002_r03.indd 648 11/18/2005 2:27:18 PM11/18/2005 2:27:18 PM © 2006 by Taylor & Francis Group, LLC MANAGEMENT OF SOLID WASTE 649 Table 15. There are additional classifications with respect to use in force in California and suggested in the new Federal Regulations. 15 There is an increase in “Sanitary Fills” and an elimination of “Dumps.” Sanitary landfill is an acceptable method of disposal of solids and provides for the ultimate disposal of many types of waste; exceptions are non-degradable materials such as plastic or aluminum which are placed in landfills. Other items mate- rial, toxic chemicals, and hazardous materials, are not allowed in landfills for safety. Where land is plentiful, or marginal areas are available for reclamation, sanitary landfills offer a number of advantages over other disposal methods including low ini- tial and operating costs. Other advantages and disadvantages are summarized in Table 16. Sanitary landfill is basically the dumping of wastes followed by compaction and the daily application of an earth cover. This situation has improved in the last decade and by the mid-1980s—all landfills will be sanitary. Several techniques are available, some of which are depicted in Figure 2, depending on the type of site available. The one constant in all operations is the daily earth cover, pref- erably a sandy loam, amounting to, usually, one part earth for every four parts refuse. Another, which is being required in new landfills, is leachate collection and treatment. In addition these types of waste disposal are limited to “non-hazardous” materials unless the landfill is especially constructed, licensed and managed. Proper site selection is as critical to a satisfactory land- fill as is sound operation. Selection criteria include proper ground and surface water drainage and isolation as well as leachate collection and treatment, to prevent pollution of the ground water table. Location in a drainage basin near streams or lakes and in or close to the ground water table present special problems and should be avoided, where pos- sible. Placement in the 100 year flood plain is prohibited. Accessibility of cover material is an important consideration. The use of tidal areas and marshes is prohibited. Dry pits, abandoned quarries and certain types of canyons of depres- sions are often satisfactory landfill sites. The size of landfills is often restricted by the amount of land available. The capacity can be estimated with a fair degree of accuracy. Refuse on arrival may vary in density from 300 to 800 pounds per cubic yard, depending on the delivery method. Typically the density in the “fill,” of the initial com- paction with a typical crawler tractor will be 1000 lbs/yd for a single lift (layer) with a depth of 20 feet of less. For mul- tiple lifts the initial density can reach 1250 lbs/yd. This initial loading increases by as much as 50% over a period of time as further compaction and decomposition takes place. 16 Much of the material in the sanitary landfill decomposes over a period of between three and ten years depending on climate, permeability of the cover, composition of the refuse and degree of compaction. The decomposition in sanitary landfills is anaerobic as compared to aerobic degradation often found in other types of fill. Temperatures typically reach 120°F in the fill as a result of the degradation. The principal gas products are carbon dioxide and methane. The greatest gas production takes place in the first two years, according to a study made at the University of Washington. Ammonia and hydrogen sulfide are not problems in sanitary landfills although small amounts of these gases are produced. Odors resulting from the decomposition of putrescible material can be controlled by observing good operating practice; that is, covering the fill continuously and sealing surface cracks. Fire hazard and insects and vermin are not a problem, as compared to dumps, in a properly operated sanitary landfill although chemical control of the latter two is sometimes required. Completed landfills are suitable for use as recreational facilities, airfields and parking areas; light industrial build- ings may be erected on landfill. Building of residential structures on fill requires special precautions because of the potential hazards associated with the evolution of methane and other decomposition gases. The cost of operating a sanitary landfill makes it an attrac- tive means of disposal where land is available. Costs for a TABLE 6 Solid wastes common Packing materials fiber metal paper plastic wood Maintenance materials paints metal grease plastic rags General housekeeping waste paper fires glass solvents industrial chemicals TABLE 7 Industry Waste for disposal thousand tons/yr Saw mills 33,000 Demolition 20,000 Food 7,200 Paper 5,000 Automobile and aerospace 1,600 Rubber 1,500 Chemical 1,400 Printing and publishing 1,300 Glass 1,400 Electronics 1,000 Wood products 3,000 Tanning 400 Paints 160 C013_002_r03.indd 649C013_002_r03.indd 649 11/18/2005 2:27:18 PM11/18/2005 2:27:18 PM © 2006 by Taylor & Francis Group, LLC 650 MANAGEMENT OF SOLID WASTE sanitary fill will vary between $3 and $10 per ton, depending on location and size of the fill. Small fills, handling less than 50,000 tons per year, will have a unit cost of $5 to $10 per ton. A large urban fill more typically shows costs of $3 to $6 per ton. The wide variation is a result of location differences, which include differences in land acquisition costs, labor costs and operating differences due to local surface conditions and requirements. The use of landfill will continue; however, its future, par- ticularly in densely populated urban areas, is in doubt. Land is at a premium for this type of application close to urban centers. What land is available must be preserved for non-combustible material and ashes. For examples, one urban county in New Jersey has less than three years landfill capacity available and in portions of Long Island no more land for landfill is available. Hauling costs too, as well as public resistance in more rural areas is making landfill less attractive for urban areas such as metropolitan New York. Finally, landfill does not provide for maximizing the value of refuse as a source of raw materials. Recent studies to find alternatives to traditional landfill practices include a demonstration of shredding prior to fill- ing. Only domestic refuse was shredded; the product was a superior fill compared to “raw” refuse. It could be left uncov- ered with satisfactory sanitary and aesthetic results and was easier to dump and compact. Flies and rats did not breed on the shredded refuse. The compacted, uncovered fill also had better weathering and load bearing characteristics. This can be achieved at a cost of about $5.00 per ton in a 65,000 ton per year operation. 17 The method has some attractive features, and some commer- cial facilities including one in Monmouth Country, NJ, which incorporates some recycle, use this principle. However, oper- ating and investment costs do appear to be higher than the more traditional method of filling “raw,” as collected, refuse. Baling of refuse may be particularly attractive where landfill sites are not locally available. A feasibility study was carried out in Chicago which showed that this method overcomes many of the present objections to landfill. The TABLE 8 Waste generation for large fi rms 13 Industrial classification Employment 1 a Annual wastes vol. Cu yd 2 b Annual wastes per employee cu yd 3 c Title Ordnance and accessories 29,356 131,404 4,476 Canning and preserving d 11,389 102,238 8,977 Other food processing (except 203) 2,012 17,545 8,720 Tobacco ee e Textiles ee e Apparel 601 1,248 2,077 Lumber and wood products ee e Furniture and fixtures ee e Paper and allied products 250 9,360 37,440 Printing, publishing and allied 968 7,020 7,252 Chemicals and allied ee e Petroleum refining ee e Rubber and plastics 481 9,069 18,854 Leather ee e Stone, clay, glass, and concrete 1,258 6,617 5,260 Primary metals ee e Fabricated metal products 3,565 47,078 13,206 Nonelectrical machinery 8,872 101,153 11,401 Electrical machinery 7,807 57,252 7,333 Transportation equipment 4,100 100,776 24,580 Instruments ee e Miscellaneous manufacturing industries ee e a Column 1: Data on employment were obtained for those large firms which were surveyed and included in the wastes calculation from the research department of the Association of Metropolitan San Jose (Greater San Jose Chamber of Commerce). b Column 2: FMC report, Solid Waste Disposal System Analysis (Preliminary Report), Tables 10 and 11, 1968. [5] c Column 3: Column 2/Column 1. d For Canning and Preserving (SIC 203), no individual firm data were available. The industry total developed for the county as a whole was divided by the total employment in the industry (specially tabulated) to arrive at the multiplier. See text for further explanation. e Data not available. C013_002_r03.indd 650C013_002_r03.indd 650 11/18/2005 2:27:19 PM11/18/2005 2:27:19 PM © 2006 by Taylor & Francis Group, LLC MANAGEMENT OF SOLID WASTE 651 Japanese have been leaders in this area using high pressure presses to provide solid cubes suitable for use in building new land in tidal areas. A facility is being successfully operated in New Jersey. More details may be found in the discussion of compaction. Incineration Incineration is essentially a method for reducing waste volume and at the same time producing an inert, essentially inor- ganic, solid effluent from material which is largely organic. Typical feed analyses are shown in Table 4. In addition to the solid product a gas is produced consisting mainly of CO 2 , H 2 , O 2 and N 2 but containing other gaseous components in tract quantities depending on the type of material burned and the operating conditions. Incineration is not an ultimate disposal method in that the solid residue which is primarily an ash containing some metal must still be disposed of, usually as landfill. The primary advantage is that it reduces the volume to be disposed of and results in a “clean” inert fill. For every 100 tons of material fed to the incinerator approximately 20 tons of residue result. The volume reduction is even more significant, often resulting in a 90% lower solids volume for organic materials. The theory of incinerator operation is very simple. A unit is designed to expose combustible material to sufficient air at high temperature to achieve complete combustion. Combustion is usually carried out in fuel beds to ensure good contact of air and refuse. Several types of configurations are used to achieve contact; these include concurrent flow of fuel and air-underfire, countercurrent flow of fuel and air-overfire, flow of fuel and air at an angle to each other—crossfeed; and combinations of these. The combustion is basically the same for all methods in that at the ignition front oxygen is rapidly consumed in the reaction O 2 ϩ C → CO 2 and if oxygen is depleted CO 2 ϩ C → 2CO. Therefore, sufficient oxygen must be available to obtain complete combustion; usually this is provided by adding addi- tional air in the chamber above the fuel. Incinerators are typi- cally operated with about 50 to 150% excess air in order that the gas temperatures do not drop below that required for good odor-free combustion; this is usually in the 1700–2300°F range. Recent trends have been to go to the higher part of this range while old units often operate at 1600°F or below. The effect of excess air on gas composition is summarized in Table 17 for a typical refuse. A detailed discussion of typical air require- ments and their effect on the thermal balance may be found in Principles and Practices of Incineration. 18 Trace components in the incinerator-start gas include some SO 2 and NO x . The former depends on the sulfur in the refuse and is typically around 0.01 to 0.02%. Nitrogen oxide is generally formed in combustion processes and depends on the amount of excess air and to some degree the operating temperature of the incinerator. Typical values of two pounds of equivalent NO 2 per ton of refuse have been reported. 19,20 FIGURE 2 Sanitary land fill operations: Credit: US Public Health Service. C013_002_r03.indd 651C013_002_r03.indd 651 11/18/2005 2:27:19 PM11/18/2005 2:27:19 PM © 2006 by Taylor & Francis Group, LLC [...]... receipt of hazardous waste application of daily cover material control of disease vectors monitoring and control of explosive gases prohibition of open burning limitation of site access control of storm water run-on and run-off limitation of surface water discharges prohibition of bulk liquids record keeping In addition to the above requirements, the proposed criteria call for site closure and post-closure... Public Works Ass’n, Inst for Solids Wastes, Municipal Refuse Disposal, Public Admin, Service, Chicago, 1970 Eliassen, R., Solid Waste Management, Off of Science and Tech., Exec Off of the Pres., Washington, 1969 Frey, D.N (Chairman), Policies for Solid Waste Management, U.S Dept NEW, PHS Pub 2018, 1970 Train, R.E (Chairman), Environmental Quality—1st Ann Report of the Council on Environmental Quality, Washington,... metals, glass and other waste Dr James Etzel of Purdue piloted a process, based on hydrapulping, which handles sewage and solid waste and yields metals and a slurry containing fine particles of glass and organics which can be further treated or used as a soil supplement Such techniques require considerable additional development and refining but will be one of the key waste management tools of the future... E and F, Washington D.C., 1966 3 Lederer, F P., Solid Waste Management, Available information materials-interim catalog, SW-58.27, USEPA, 1977 34 1 35 36 37 38 39 REFERENCES 40 1 United States Environmental Protection Agency, The Solid Waste Dilemma: An Agenda for Action 2 PL 9 8-6 16, The Hazardous and Solid Waste Amendments of 1984, USC 6901, November 8, 1984 3 PL 9 4-5 80, Resource, Conservation and. .. Act of 1976, USC 6901, October 21, 1976 Section 1004 4 40 CFR 261 5 Op cit PL 9 4-5 80 6 Eliassen, R., Solid Waste Management, Off of Science and Tech Exec Off of the Pres., Washington (1969) 7 Amer Pub Ass’n Inst for Solid Wastes, Municipal Refuse Disposal, Public Administration Service, Chicago, p 11–20, 1970 8 Ibid., p 52 9 Amer Pub Works Ass’n, Comm on Solid Wastes, op cit p 47 10 Carruth, D.E and. .. Waste Incineration, ASME, Nat’l But of Stds Report NBSIR 7 8-1 479, 1978 Reutilization, Recycle and Resource Recovery 1 Drobny, N.L., H.E Hull, and R.F Testin, Recovery and Utilization on Municipal Waste, SW-10c, USEPA, 1971 © 2006 by Taylor & Francis Group, LLC C013_002_r03.indd 666 11/18/2005 2:27:23 PM MANAGEMENT OF SOLID WASTE 2 Darnay, A and W.E Franklin, Salvage Markets for Materials in Solid Wastes,... Ass’n, Inst for Solid Wastes, op Cit 3 Copp, W.R et al., Technical-Economic Study of Solid Waste Disposal Needs and Practices, 1, Municipal Inventory, 2, Industrial Inventory, U.S Dept HEW, PHS Pub No 1886, Washington, 1969 4 Darnay, A J Jr and W.E Franklin, The Role of Packaging in Solid Waste Management, U.S Dept HEW, PHS Pub No 1885, Washington, 1969 5 Black, R.J et al., The National Solid Wastes Survey,... Chapter VI, 1970 Hanks, T.G., Solid Wastes/Disease Relationships, U.S Dept HEW, PHS Pub No 999-UIH-6, Cincinnati, 1967 Cooke, L.M (Chairman), Cleaning Our Environment, The Chemical Basis for Action, ACS, Washington, 1969 Pavoni, J.L et al., Handbook of Solid Waste Disposal, Van Nostrand, New York, 1975 1 Golueke, C.G and P.H McGauhey, Comprehensive Studies of Solid Waste Management, U.S Dept HEW, PHS... Sanitary Landfill Design and Operation, Rep No SW-65ts, USEPA,1972 5 Classifying Solid Waste Disposal Facilities, SW-828, USEPA, 1980 6 Toxicity of Leachates, EPA-600/ 2-8 0-0 57, USEPA, 1980 Disposal methods, incineration 1 Corey, T.C (ed.), Principles and Practices of Incineration, Wiley, New York, 1970 2 DeMarco, J et al., Incinerator Guidelines, U.S Dept HEW, PHS Pub 2012, Washington, 1969 3 Day and Zimmerman,... C.L., Solid Waste, Wiley-Interscience, New York, 1975 Sources Some Special Problems Radioactive solid wastes create special problems and are discussed elsewhere in a section on Radioactive Wastes Industrial wastes, as mentioned previously, has been dumped as a general rule Because of the high specialized nature of industrial wastes, it is impossible to discuss them in a general way Total recycling of . disposal of solids. Prior to that it was “out -of- sight, out -of- mind.” With ever growing amounts of solid waste as detailed in the discussion on sources, and con- cerns about pollution of ground and. Institute for Solid Waste of the American Public Works Association and the Office of Solid Waste Management of the Environmental Protection Agency. 7 The standard usage of terms detailed. use of tidal areas and marshes is prohibited. Dry pits, abandoned quarries and certain types of canyons of depres- sions are often satisfactory landfill sites. The size of landfills is often

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  • TABLE OF CONTENTS

  • CHAPTER 2: MANAGEMENT OF SOLID WASTE

    • INTEGRATED WASTE MANAGEMENT

    • LEGISLATION

    • INTRODUCTION

    • REGULATION OF SOLID WASTE MANAGEMENT

    • SOURCES OF WASTE

      • Urban Waste

      • Industrial Wastes

      • Agricultural Wastes

      • Mineral Wastes

      • Hazardous Wastes

      • Processing Methods

      • Sanitary Landfill

      • Incineration

      • Refuse-Derived Fuel

      • Compaction

      • Composting

      • The Economics of Waste Disposal

      • Reclamation, Reuse and Conversion

      • SOURCE REDUCTION

        • Location Restrictions: Areas of Special Concern

        • Operating Criteria: Minimum Requirements

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