Waste Reclamation

T0252 Energy Products of Idaho, Fluidized-Bed Combustion T0253 Energy Reclamation, Inc., Pyrolytic Waste Reclamation (PWR)... 

E. SNAPE obtained his BS and PhD degrees in Metallurgical Engineering from the University of Leeds in 1965. During his research career with Inco, he received numerous awards for his work on stress corrosion and hydrogen embrittlement, and became an international authority on this subject. In 1974, Dr. Snape pioneered the development of a waste reclamation process which now is being applied to the recovery... 

Industrial waste reclamation. A very wide field, in many cases requiring microfiltration or ultrafiltration pretreatment to condition the water prior to the RO membrane. Piloting is often required due to the one-off nature of these streams. Some thought at the design stage for industrial plant may identify some waste streams that are easily treated for recycle— they should be kept separate from the difficult streams. 

Removing suspended inorganic material from waste streams generated in the beneficiation of ores or nonmetalHc minerals, to form a concentrated slurry that can be used for reclamation of mined out areas or other uses and a clarified water that can be discharged or recycled. 

Commercially, a small amount of the 4,4 -MDA is isolated by distillation from PMDA. Depending on the process employed, the removal of MDA can be partial (as is done with the isocyanates) or total. Partial removal of MDA gives some processiag latitude but yields of 4,4 -MDA are reduced. Distillation residues from PMDA manufacture that contain less than 1% MDA pose a disposal problem. Processes for the regeneration of MDA by heating these residues ia the presence of aniline and an acid catalyst have been patented (33—35). Waste disposal of PMDA is expensive and reclamation processes could become commercially viable. The versatility of the isocyanate process, however, can be used to avoid the formation of low MDA content distillation residues. 

Preparation of Collected Materials. The actual amount of recovered MSW that can be recycled to meet buyers quaUty specifications is highly dependent upon how the material is collected and processed. There are primarily three methods available to collect MSW for recycling mixed waste, waste with commingled recyclables, or waste with separated recyclables. Which method of collection is chosen, in turn, determines the amount of preparation that is needed prior to reclamation and reuse. 

Much of the technology used in the reclamation of metals from metal-bearing wastes was developed by the mining iadustries. The primary means of recycling metal from metal and alloyed scrap is via pyrometaHurgy (see Metallurgy). 

Recovered copper in electronic scrap (old) is small in comparison representing about 14,000 t/yr of copper from 68,000 t/yr of waste (25). Electronic scrap accounts for iron (27,000 t), tin (14,000 t), nickel, lead, and aluminum (6,800 t each), and zinc (3,500 t). Precious metal value, which is the primary economic reason for the reclamation of electronic waste, accounts for 345 t of gold, twice that in silver, and some palladium. 

In spite of these efforts, significant quantities of metal-bearing wastes, ha2ardous or not, continue to be earmarked for disposal rather than reclamation. There are several reasons. Often the wastes are mixed from several process streams, contain relatively low concentrations of many recoverable metals, and may contain high concentrations of water, silicates, and secondary metals, such as calcium and iron. 

World capacity and demand for tetrachloroethylene were approximately 1100 and 845 thousand metric tons ia 1974, respectively. Although demand iacreased iato the mid-1980s, siace then demand for tetrachloroethylene has decreased significantly as a result of the phaseout of chlorofluorocarbons, the use of more efficient dry-cleaning equipment, and iacreased reclamation of waste solvent. World capacity and demand as of 1988 are provided ia Table 2 Several United States manufacturers have shut down faciUties ia the last fifteen years. Current manufacturers and their capacities are Hsted ia Table 3. United States production and sales history is shown ia Table 4. 

Chlorination was found (172) to be the most suitable and effective method for decolori2ing and reducing the COD of waste dyebaths containing a2o dyes. These findings have been substantiated for chlorination and biochemical purification (173). A study (174) has been done on the technical and economic feasibiUty of a chlorination dye wastewater reclamation system for treating effluent that is suitable for reuse in dyeing of polyester/cotton blends with disperse and direct dyes. 

Waste Minimization source reduction, certain types of recycling and reclamation. Waste minimization does not include recycling activities whose uses constitute disposal and burning for energy recovery. 

On land, too, there are changes in the way plastics are disposed of. In the UK some local authorities are actively promoting recycling of plastic bottles and poly(styrene) containers, for example by schemes where local residents place recyclable materials in designated boxes for refuse collectors. These boxes are taken to a Materials Reclamation Facility for final sorting of the plastics waste. 

Materials Reclamation Weekly 163, No.22, 29th July 1994, p.6 GOVERNMENT GIVES THUMBS UP FOR WASTE-TO-ENERGY... 

When nonrenewable mineral resources are processed for metal extraction and the metals extracted are utilized in various ways and in diverse forms, they become potentially available for reclamation and recycling. Recycled metals produced by the extraction and refining of metallic wastes are known as secondary metals, whereas metals produced from primary ores are termed primary metals. A classification of recyclable metalliferous resources such... 

None of the calves of 10 cows showed clinical signs of neurotoxicity after the cows were orally exposed to an unknown quantity of a Fyrquel hydraulic fluid reclamation waste that according to the authors possibly contained tri-ort/20-cresyl phosphate (TOCP), and that was applied liberally to their backs one time as a treatment for ringworm (Julian et al. 1976). The cows were seen licking their backs and the backs of other cows thus, the cows were orally and dermally exposed to organophosphate ester hydraulic fluids. 

No deaths occurred in rats after dermal exposure to Durad 220B, Durad 300, or Durad 110 under occluded conditions for 24 hours at dosage levels of 2,000 mg/kg (FMC 1990a). Dermal exposure to 2,890 mg/kg doses of a cyclotriphosphazene hydraulic fluid for 24 hours under occluded conditions likewise produced no deaths in rabbits (Kinkead et al. 1992c MacEwen and Vernot 1985). Deaths associated with severe cholinergic symptoms and symptoms of delayed neuropathy occurred in a group of 50 cattle treated dermally with about 1.52 L of waste from reclamation of a Fyrquel hydraulic fluid (Julian et al. 1976). 

After a single dermal exposure to waste from the reclamation of a Fyrquel hydraulic fluid that may have been contaminated with tri-or/7 o-cresyl phosphate (TOCP), no apparent signs of neurotoxicity were observed in calves of 10 cows that manifested neurotoxicity just after the birth of the calves. The cows were apparently also exposed orally concurrent to the dermal exposure (Julian et al. 1976). No intermediate- or chronic-duration dermal studies examining developmental effects in animals were located. 

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