Waste streams from manufacture

Except for occupational settings, no information was formd in the available literature on eoncentrations of HDl or HDl prepolymers in air. Because of the relatively short atmospheric half-life (approximately 2 days) from reaction with hydroxyl radicals (see Section 5.3.2.1), significant atmospheric concentrations of HDl would be expected to be found only near sources of this substance (e.g., waste streams from manufacturing or processing facilities, hazardous waste sites, occupational settings). Atmospherie eoneentrations of HDl and HDI-BT found in occupational settings are siunmarized in Section 5.5. 

The advantages of this process arise finm the fact that the system does not t3q)ically require chemicals and, therefore, the decomposition of organics is an environment-friendly degradation process. However, this process has limitations and cannot handle slurries, tars, or a high concentration of suspended solids. In fact, this process has been used extensively to treat waste streams from iron and steel, pulp and paper, petroleum refining, organic chemical manufacture, and pharmaceutical industries. 

It is required to design a plant to clean 15,000 gpd of the following waste stream from a wafer fabrication/computer manufacturing facility ... 

The waste streams from a tetraalkyllead manufacturing plant contain significant concentrations of both inorganic and organic lead. The inorganic lead can readily be treated by conventional precipitation but this has little or no effect on the organic lead, which is usually present as soluble alkyllead salts. A number of methods have been proposed to reduce the organic lead concentrations, typically 1-100 mg (Pb) dm", to less than 1 mg dm". ... 

In 1980, approximately 111,000 t of synthetic organic dyestuffs were produced in the United States alone. In addition, another 13,000 t were imported. The largest consumer of these dyes is the textile industry accounting for two-thirds of the market (246). Recent estimates indicate 12% of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants (3). 

Two major sources of H2S emissions from the process are the acid gas stream evolving from hydrogen manufacture, Ri, and the gaseous waste emitted from the separation... 

Principal Wastes or Pollutants in Wastewater Streams from Various Battery Manufacturing Plants... 

In a completely different area, the setting of minimum detectable levels, the politically expedient method may be counter productive to the expansion of knowledge. Dr. Kurtz related an example of this "We had a local manufacturer dribble amounts of kepone and mirex in the local streams from waste disposal on their site. At one point a few wells of homeowners along the stream were found to contain kepone at levels in the low parts per trillion. Later in annual state testing programs these wells were found not to contain any kepone. Was there a lowering of contamination What had probably happened was that the minimum detectable level was set above most of these early levels, and the later samples were less than this minimum level. It took on a suspicious air that the state had purposely set this level to avoid future controversy in this area."... 

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