Wastes, industrial types

Waste Treatment. Environmental concerns have increased the need to treat Hquid discharges from all types of industrial processes, as well as mnoffs where toxic substances appear as a result of leaks or following solubilization (see Wastes, industrial). One method of treatment consists of an ion-exchange system to remove the objectionable components only. Another involves complete or partial elimination of Hquid discharges by recycling streams within the plant. This method is unacceptable unless a cycHc increase in the impurities is eliminated by removing all constituents prior to recycling. 

The surviving U.S. plants have embraced all types of waste treatment processes (see Wastes treatment, hazardous waste Wastes, industrial). The most desired poUution prevention processes are those which reduce the total amount of waste discharged. Treatment and disposal are less strongly emphasized options. Zero wastewater discharge faciHties and water recycling processes are becoming more common (55,56). 

Sewage and organic industrial wastes This type of pollution adversely affects the oxygen content of water (BOD, biological oxygen demand). 

It is the roughly 7 percent of solid wastes produced by industrial and energy-generation operations and the 3 percent produced by nonindustrial human activities that present the most serious environmental problems in the United States today. These fall into three large categories (1) pure volume of wastes, (2) hazardous wastes, and (3) radioactive wastes. Each type of solid waste poses its own set of problems and requires its own set of solutions. 

The formulation of the polymer used in filtration varies with the waste stream type. Different polymers have different costs. The operating expenses associated with treating wastewater contaminated with nickel and zinc from the electroplating industry was estimated to be less than 1 cent per gallon (D21214W, p. 6). 

Manual Component Separation The manual separation of solid-waste components can be accomplished at the source where solid wastes are generated, at a transfer station, at a centralized processing station, or at the disposal site. Manual sorting at the source of generation is the most positive way to achieve the recovery and reuse of materials. The number and types of components salvaged or sorted (e.g., cardboard and high-quality paper, metals, and wood) depend on the location, the opportunities for recycling, and the resale market. There has been an evolution in the solid waste industry to combine manual and automatic separation techniques to reduce overall costs and produce a cleaner product, especially for recyclable materials. 

Despite the paucity and uncertainty of existing data, some states and industries recognized early on that not all hazardous waste facilities pose the same t> pe or level of risk to the environment. California, lexas, Michigan, and Washington State have developed wastes into specific categories to acliieve appropriate levels of regulation. Information on the toxicity and health effects of wastes (or their major components), for example, has been used to define waste categories. Similarly, it is possible to divide up facilities and then match classes of wastes to types of facilities. 

Industry type (Standard Industrial Classification Code) Total waste quantity disposed of in all on-site industrial facilities (thousand tons) Percent of waste disposed of in landfills Percent of waste disposed of in surface impoundments Percent of waste disposed of in land application units Percent of waste disposed of in waste piles... 

Only a minute fraction, about 0.1%, of the total lead consumed by the battery industry enters into the manufacture of small consumer type lead-acid batteries, and they are likely to be discarded as part of general household waste. The recycling of batteries in that category may be handled by processes described in Section 5.3 below. Almost all the leadf consumed by the battery industry is employed in the manufacture of large prismatic automotive and industrial type batteries. 

One of the basic problems of the nuclear power industry is avoidance of environmental pollution, which is directly related to the necessity of reliable burial of radioactive waste. One type of waste comprises ion-exchange resins used to purify process waters and render them free of radioactive cations. The problem of disposal of used radioactive ion-exchange resins is rather difficult and we have suggested using Silor composition for this purpose. This composition envelops the swollen... 

In spite of many different applications of polymers in all fields of our life only 0.6 % of the whole waste amount are falling to plastics. All over, in Western Europe in 1993 2.8 billion refuse of all type was proved (household, agricultural waste, industrial waste, electrical/electronical scrap, building refuse etc.). From this amount the plastics waste is only 16.2 million t. In the waste stream the largest fraction is the household plastics waste, like shown in table 3 ... 

Industry types of hazardous-waste generators can be divided among the seven following major categories, each containing some of 10-20 % of hazardous waste... 

TABLE 2.4 Potential for Waste Reduction Opportunities across Different Industry Types... 

Rotary Kiln Incinerators. The rotary kiln has been used to incinerate a large variety of Hquid and soHd industrial wastes. Any Hquid capable of being atomized by steam or air can be incinerated, as well as heavy tars, sludges, pallets, and filter cakes. This abiUty to accept diverse feeds is the outstanding feature of the rotary kiln and, therefore, this type of incinerator is often selected by the chemical and waste treatment industries. 

The wide range of types of paper products results in a variety of sludges. SoHd wastes result from several sources within the mill, eg, bark, sawdust, dirt, knots, pulpwood rejects, flyash, cinders, slag, and sludges. Sludges often are disposed of in combination with residuals from other sources. Approximately 300 kg of soHd waste per ton of finished product is generated by the pulp and paper industry. 

The type of paperboard used by the carton industry is boxboard. Boxboard may be categorized, based on the raw material, as combination or soHd boxboard. Combination boxboard, of which there are many grades, normally is made on a multicylinder paper machine using a substantial percentage of waste paper with virgin pulp. SoHd boxboard usually is made on a Fourdrinier paper machine using only virgin pulp and it is bleached or coated. 

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