Toxic liquid waste

PACT [Powdered activated carbon treatment] A wastewater treatment process which combines activated carbon treatment with biological treatment, providing a single-stage treatment of toxic liquid wastes. Developed by DuPont in the 1970s at its Chambers Works, Deepwater, NJ, and now licensed by U.S. Filter/Zimpro. More than 50 units were operating in 1990. 

Noncombustible or toxic liquid wastes that do not lend themselves to disposal by any of the means just outlined are the most difficult to dispose of safely. These kinds of wastes provide the strongest incentive for a producer to develop a use of the waste stream to minimize ultimate disposal costs. Thus, acidic pickling plant wastes, which contain iron plus unused sulfuric or hydrochloric acids may be used to precipitate phosphate from secondary sewage effluent (e.g., Eq. 5.25). Or they may be blended with aqueous alkaline wastes containing phenolate and unexpended sodium hydroxide to neutralize the pH extremes of both streams. 

Toxic—Liquid wastes or extract from waste solids that fail the Toxicity Characteristic Leaching Procedure (TCLP) analytical test because they contain certain designated metals, pesticides, or organic chemicals at concentrations equal to or, in excess of, specified regulatory limits. 

Effective and proved teohnologies Toxic liquid waste... 

Information provided in Part III. Section 8. of Form R is optional. In this section, you may identify waste minimization efforts relating to the reported toxic chemical. Waste minimization reduces the amount of the toxic chemicai in wastes by reducing waste generation or by recycling. This can be accomplished by equipment changes, process modifications, product reformulation, chemical substitutions, or other techniques. Waste minimization refers exclusively to practices which prevent the generation of wastes. Treatment or disposal does not minimize waste and should not be reported In this section. Recycling or reuse of a toxic chemical is considered waste minimization. Waste minimization applies to air emissions and wastewater, as well as to liquid or solid mate-... 

The submitters recommend collection of solid wastes in an appropriate solid waste container, and liquid wastes (filtrates containing thallium residues, etc.) in suitably labeled bottles or cans. For the disposal of thallium wastes, a commercial organization specializing in the disposal of toxic materials was employed. The submitters understand that the disposal procedure consists of burying thallium wastes in deep pits after covering with sand. 

Solid waste can be burnt in suitable incinerators or disposed by burial at licensed land-fill sites. As for liquid wastes, the dumping of toxic solid waste at sea is now not acceptable. 

ATP measured by luciferin-luciferase BL assay was used to examine the effect of toxic substances on whole microbial communities in activated sludge mixed liquid samples [114], It was used to detect whether wastewater had an effect on the biodegradation capability of the resident population of microorganisms. Actually ATP BL represents an important rapid toxicity test that utilizes waste treatment natural microorganisms to determine the toxicity of wastes discharged to the sewer [132],... 

Biological toxicity tests are widely used for evaluating the toxicants contained in the waste. Most toxicity bioassays have been developed for liquid waste. Applications of bioassays in wastewater treatment plants fall into four categories [19]. The first category involves the use of bioassays to monitor the toxicity of wastewaters at various points in the collection system, the major goal being the protection of biological treatment processes from toxicant action. 

The liquid-liquid, acid-base fractionation method was preferred over HPLC by the liquid waste panel members because it is a better validated technique for the isolation of components that are toxic or that might otherwise interfere with the assay. Also, the distribution of activity in the acid, base, and neutral fractions provides a preliminary estimate of the types of chemicals responsible for the mutagenicity. 

The restrictions on the land disposal of many wastes have increased the cost of hazardous waste disposal. The land disposal restrictions that affect metal fabricators have been in effect for several years. For example, the restrictions on the land disposal of liquid wastes containing toxic metals and/or acids began on January 1,1984 (Section 66905 CCR). These restrictions have caused increases in disposal costs since these wastes now require some form of treatment prior to land disposal. These increased waste disposal costs are viewed as a driving force for the metal finishing industry to implement waste reduction technologies. 

Energy And Environmental Considerations. The energy requirements to produce malic acid via conventional processes are fairly moderate Malic acid production generates low levels of solid, airborne, and liquid waste. Solid waste is primarily non toxic malic acid salts resulting form regenerating carbon cells and ion-exchanfle resins Airborne emissions ate... 

In the event of a major plant accident, large quantities of nitrogen oxides could be released into the atmosphere and product nitric acid may well be released to the drains. There is little that can be done to provide for such a situation. The emphasis would be on dilution of any liquid wastes expelled. It would be left to the prevailing winds to disperse the nitrogen oxide cloud. Fortunately this gas cloud is not flammable, but it is highly toxic. Nitrogen oxide fumes either from nitric acid or from process gases may have a deceptive delayed action. The victim may feel no pain or discomfort at the time of the low-level inhalation, or for up to 48 hours thereafter, but then serious respiratory and cardiac problems can occur. 

Recommendation 3b. The Army should identify toxic agent reaction products likely to be present at potentially harmful levels in liquid-phase process streams, liquid wastes, and solid wastes, including waste streams generated during closure activities. 

The PEEP scale is a cost-effective tool to determine the toxic loading potential of a series of point source liquid wastes discharging to a common receiving environment, owing to the use of small-scale bioassays. 

While the PEEP index can theoretically be employed to assess the toxic potential of varied liquid media and groups of specific chemical products of interest (Section 8.3), it was originally conceived to appraise that of liquid wastes of point source discharges to aquatic environments. The index is thus described for this purpose in this section. 

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