Disposal and Recovery

Piping, Ducting, Dampers and Fans 8300-8399. .Waste Disposal and Recovery 8900-8999. .Hlace1laneoua (Wet Scrubbers) 8500-8599 -Dry Scrubbers 6550-8580. Precipitators... 

SANTOLERI, J. J. (1973) Chem. Eng. Prog. 69 (Jan.) 69. Chlorinated hydrocarbon waste disposal and recovery systems. 

Stewart, T. L., and J. N. Hartley. 1985. Evaluation of Improved Chemical Waste Disposal and Recovery Methods for N Reactor Fuel Fabrication Operations 1984 Annual Report. PNL-5294 and UNI-3204, Pacific Northwest Laboratory, Richland, Washington. 

Notes. (1) This technique, rather than conventional filtration, is to be preferred in this case owing to the high volatility of the hydrocarbon. For details on the disposal and recovery of the catalyst see Section 2.17.1, p. 89, Hydrogenation at atmospheric pressure (12). 

First, the processing of inhibited plastics into products is accompanied by the liberation of harmful and toxic matter into the environment. In particular, these are volatile fractions of VCI, other engineering additives and thermal destruction products of the plastics. Second, the majority of inhibited plastic goods are expendable and their disposal and recovery pose a serious technological and organizational problem. The expediency and efficiency of using inhibited plastics as a rustproof method relies on a successful solution of this problem. 

Austria Take-back and recovery obligations since 1992 of refrigeration equipment Assessing voluntary plan for disposal and recovery of electronic waste... 

The derivatives are hydroxyethyl and hydroxypropyl cellulose. AH four derivatives find numerous appHcations and there are other reactants that can be added to ceUulose, including the mixed addition of reactants lea ding to adducts of commercial significance. In the commercial production of mixed ethers there are economic factors to consider that include the efficiency of adduct additions (ca 40%), waste product disposal, and the method of product recovery and drying on a commercial scale. The products produced by equation 2 require heat and produce NaCl, a corrosive by-product, with each mole of adduct added. These products are produced by a paste process and require corrosion-resistant production units. The oxirane additions (eq. 3) are exothermic, and with the explosive nature of the oxiranes, require a dispersion diluent in their synthesis (see Cellulose ethers). 

Thorium, uranium, and plutonium are well known for their role as the basic fuels (or sources of fuel) for the release of nuclear energy (5). The importance of the remainder of the actinide group Hes at present, for the most part, in the realm of pure research, but a number of practical appHcations are also known (6). The actinides present a storage-life problem in nuclear waste disposal and consideration is being given to separation methods for their recovery prior to disposal (see Waste treati nt, hazardous waste Nuclear reactors, waste managet nt). 

Municipal Solid Waste. In the eady 1990s, the need to dispose of municipal soHd waste (MSW) ia U.S. cities has created a biofuels industry because there is Htde or no other recourse (107). Landfills and garbage dumps are being phased out ia many communities. Combustion of MSW, ie, mass-bum systems, and RDF, ie, refuse-derived fuel, has become an estabhshed waste disposal—energy recovery industry. 

Some of the economic hurdles and process cost centers of this conventional carbohydrate fermentation process, schematically shown in Eigure 1, are in the complex separation steps which are needed to recover and purify the product from the cmde fermentation broths. Eurthermore, approximately a ton of gypsum, CaSO, by-product is produced and needs to be disposed of for every ton of lactic acid produced by the conventional fermentation and recovery process (30). These factors have made large-scale production by this conventional route economically and ecologically unattractive. 

The Resource Conservation and Recovery Act (RCRA) controls the disposal of ha2ardous waste. SARA Tide III governs the toxic iaventory and emission reporting the Clean Water Act (CWA) sets the limits for metals that can be present ia water discharge and the Clear Air Act (CAA)... 

Clean Air Act and its amendments ia 1970, 1977, and 1990 1967 Air Quahty Standards and National Air Pollution Acts and 1970 National Environmental PoHcy Act) (2) better waste disposal practices (1965 SoHd Waste Disposal Act 1976 Resource Conservation and Recovery Act) (see Wastes, industrial Waste treatment, hazardous wastes) (i) reduced noise levels (1972 Noise Control Act) (4) improved control of the manufacture and use of toxic materials (1976 Toxic Substances Control Act) and (5) assignment of responsibiUty to manufacturers for product safety (1972 Consumer Product Safety Act) (15,16). 

Solid and Hazardous Waste. Regulation of pollution resulting from soHd waste disposal was formulated at a much slower pace than regulation of air or water pollution. It was not until the Resource Conservation and Recovery Act (RCRA) of 1976 (6) was passed that substantial controls were authorized. 

The main objectives of RCRA ate to protect pubHc health and the environment and to conserve natural resources. The act requires EPA to develop and adininistet the following programs soHd waste disposal practices providing acceptable protection levels for pubHc health and the environment transportation, storage, treatment, and disposal of hazardous wastes practices that eliminate or minimize hazards to human health and the environment the use of resource conservation and recovery whenever technically and economically feasible and federal, state, and local programs to achieve these objectives. 

Transportation and Disposal. Only highly alkaline forms of soluble sihcates are regulated by the U.S. Department of Transportation (DOT) as hazardous materials for transportation. When discarded, these ate classified as hazardous waste under the Resource Conservation and Recovery Act (RCRA). Typical members of this class are sodium sihcate solutions having sihca-to-alkah ratios of less than 1.6 and sodium sihcate powders with ratios of less than 1.0. In the recommended treatment and disposal method, the soluble sihcates are neutralized with aqueous acid (6 Af or equivalent), and the resulting sihca gel is disposed of according to local, state, and federal regulations. The neutral hquid, a salt solution, can be flushed iato sewer systems (86). 

Antimony may enter the human body through the consumption of meats, vegetables, and seafood which all contain about 0.2—1.1 ppb antimony. Disposal of Antimony. Antimony and its compounds have been designated as priority pollutants by the EPA (35). As a result users, transporters, generators, and processors of antimony-containing material must comply with regulations of the Eederal Resource Conservative and Recovery Act (RCRA). 

Reclamation, Disposal, and Toxicity. Removal of poisons and inorganic deposits from used catalysts is typically difficult and usually uneconomical. Thus some catalysts are used without regeneration, although they may be processed to reclaim expensive metal components. Used precious metal catalysts, including automobile exhaust conversion catalysts, are treated (often by the suppHers) to extract the metals, and recovery efficiencies are high. Some spent hydroprocessing catalysts may be used as sources of molybdenum and other valuable metals. 

By-Products. The biomass from the fungal fermentation process is called mycellium and can be used as a supplement for animal feed since it contains digestable nutrients (25,26). The lime-sulfuric purification and recovery process results in large quantities of calcium sulfate cake, which is usually disposed of into a landfill but can find limited use in making plaster, cement, waUboard, or as an agricultural soil conditioner. The Hquid extraction purification and recovery process has the advantage of Htde soHd by-products. 

The introduction of surfactant products into the environment, after use by consumers or as part of waste disposed during manufacture, is regulated by the Clean Water Act, the Clean Air Act, and the Resource Conservation and Recovery Act. In this respect, surfactants are subject to the same regulations as chemicals in general. There are, however, two areas of specific relevance to surfactants and detergent products, ie, biodegradabiUty and eutrophication. 

---