Waste from effluent plants

The depressed prices of most metals in world markets in the 1980s and early 1990s have slowed the development of new metal extraction processes, although the search for improved extractants continues. There is a growing interest in the use of extraction for recovery of metals from effluent streams, for example the wastes from pickling plants and electroplating (qv) plants (276). Recovery of metals from Hquid effluent has been reviewed (277), and an AM-MAR concept for metal waste recovery has recentiy been reported (278). Possible appHcations exist in this area for Hquid membrane extraction (88) as weU as conventional extraction. Other schemes proposed for effluent treatment are a wetted fiber extraction process (279) and the use of two-phase aqueous extraction (280). 

Table 1 can be used as a guide to define hazardous wastes from textile plants. Besides the direct toxicity of substances like chlorinated hydrocarbons, organo-Hg compounds, or concentrated alkaline solutions, other parameters have been defined with regard to problems during biodegradation or accumulation in the sludge from CWWT. A particular situation is found with colored effluents, where limits for spectral absorption have been defined. While the toxicity of textile dyes is comparably low, these limits were derived from the visual aspect of the water released from a textile plant because they look unhealthy. ... 

The liquid effluent plant which is a tertiary treatment facility that removes process wastes from the plant liquid discharge,... 

Industrial Wastewater Treatment. Industrial wastewaters require different treatments depending on their sources. Plating waste contains toxic metals that are precipitated and insolubiHzed with lime (see Electroplating). Iron and other heavy metals are also precipitated from waste-pidde Hquor, which requires acid neutralization. Akin to pickle Hquor is the concentrated sulfuric acid waste, high in iron, that accumulates in smokeless powder ordinance and chemical plants. Lime is also useful in clarifying wastes from textile dyeworks and paper pulp mills and a wide variety of other wastes. Effluents from active and abandoned coal mines also have a high sulfuric acid and iron oxide content because of the presence of pyrite in coal. 

Americium is released into surface water primarily from plutonium production reactors, nuclear fuel reprocessing facilities, or in nuclear accidents. It may also be released from radioactive waste storage facilities. Since 241Pu decays into 241 Am,241 Am is also released as a result of 241Pu releases. Water sampling data were used to estimate effluent releases from the SRS from the plant s start up in... 

Phenol has been detected in the effluent discharges of a variety of industries. It was found in petroleum refinery waste water at concentrations of 33.5 ppm (Pfeffer 1979) and 100 ppb (Paterson et al. 1996), in the treated and untreated effluent from a coal conversion plant at 4 and 4,780 ppm, respectively (Parkhurst et al. 1979), and in shale oil waste water at a maximum of 4.5 ppm (Hawthorne and Sievers 1984). It has also been detected in the effluent from a chemical specialties manufacturing plant at 0.01-0.30 ppm (Jungclaus et al. 1978), in effluent from paper mills at 5-8 ppb (Keith 1976 Paterson et al. 1996), and at 0.3 ppm in a 24-hour composite sample from a plant on the Delaware River, 2 and 4 miles downriver from a sewage treatment plant (Sheldon and Hites 1979). 

Plant 3920 is a bituminous coal- and oil-fired plant with a generating capacity of 557 MW. This plant uses 1,220,000 Mg/year of coal. An ash settling pond was used to remove wastes from coal pile runoff, regeneration wastes, and fly ash. The influent data were obtained from the pond inlet whereas the effluent data were from the discharge stream to the river. The results of this treatment are shown in Table 9. 

The list of plants, by-products and waste materials that can potentially be used as feedstock is almost endless. Major resources in biomass include agricultural crops and their waste by-products, lignocellulosic products such as wood and wood waste, waste from food processing and aquatic plants and algae and effluents produced in the human habitat. Moderately dried wastes such as wood residue, wood scrap and urban garbage can be directly burned as fuel. Energy from water-containing biomass... 

Waste water effluents from coal gasification facilities contained p-cresol at concentrations of 880 mg/L (Neufeld et al. 1985) and 5,120 ppb (Pellizzari et al. 1979). A coal liquefaction and a shale oil waste water effluent contained p-cresol at concentrations of 420 mg/L (Fedorak and Hrudey 1986) and 779 pg/L (Pellizzari et al. 1979), respectively, p- Cresol was emitted with the waste water of a poultry processing plant at concentrations ranging from 2.14 to 22.5 mg/L (Andelman et al. 1984). 

Waste water effluents from coal gasification plants contained p- and m- cresol at a combined concentration of 1,840 mg/L (Giabbai et al. 1985). p- and m-Cresol were detected at a combined average concentration of 1.0 yg/L for three samples of retort water from a shale oil production facility (Hawthorne and Sievers 1984). 

Domestic waste water is the major anthropogenic source of nickel in waterways (Nriagu and Pacyna 1988). Concentrations of nickel in influents to 203 municipal waste-water treatment plants (9,461 observations) ranged from 2 to 111,400 pg/L the median value was 300 pg/L (Minear et al. 1981). Concentrations in treated effluents were not reported. However, nickel may be removed by chemical precipitation or coagulation treatment in publicly owned treatment works, which reduces nickel releases (EPA 1981). 

The total volume of waste (including returned concrete plant mixer washout, washdown of truck, spillage of concrete and silt from yard washing) can exceed 140 t per year for a six-truck ready-mixed operation [87]. Environmental protection acts in Western Europe and North America now prohibit the disposal of concrete waste in landfill sites. Ready-mixed concrete operations have therefore altered procedures for disposal of alkaline waste and effluent. One such procedure where significant progress has been made is in the use of chemical admixture systems to eliminate washout from ready-mixed trucks. 

Polybrominated Biphenyls. Only limited data on the levels of PBBs in ambient air are available (DeCarlo 1979). Data are available on the levels of PBBs in effluent water from manufacturing plants, in river water, stream sediment, and soil in the vicinity of the plants, in sludge of a waste treatment plant, and in groundwater of a landfill site (Hesse and Powers 1978 Shah 1978). No data on the level of PBBs in drinking water from the contaminated sites were located. No estimate on the human intake of PBBs from any of the various environmental media was located in the literature. 

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