Waste environmental concerns

Synthetic Processes. Traditional Solvay plants produce large volumes of aqueous, chloride-containing waste which must be discharged. This fact, in addition to a noncompetitive cost position, is largely responsible for the demise of U.S. synthetic plants. In countries other than the United States, waste is sent to the ocean, rivers, or deep underground wells. The AC and NA coproduct processes produce less aqueous waste than the traditional Solvay and NA mono processes. Related environmental concerns are added whenever a plant complex includes lime quarries and ammonia-producing equipment. 

Developments in hydiaulic fluids are driven by environmental concerns including disposal of waste, waste rninirnization, biotoxicity, effects on human... 

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. 

Managerial information environmental policies and procedures prioritization of waste-management concerns automated or computerized waste-management systems inventory and distribution procedures maintenance schediiling practices planned modifications or revisions to existing operations that would impact waste-generation activities and the basis of source reduction decisions and policies... 

The past two decades have seen an increased social awareness of the impact of modern-day hfestyles on the environment. Pubhc environmental concerns include issues such as waste disposal hazardous-material regulations depletion of natural resources and air, water, and laud pollution. Nevertheless, roughly one-half of the total quau-... 

There is now a marked pause in the construction and deployment of new nuclear power plants. Although some construction of reactors continues in Asia and Eastern Europe, a de facto moratorium exists in the United States and in most of Europe, while in Sweden and Gennany the governments plan to shut down operating plants before the end of their normal lifetimes. The inhibitions on nuclear power development stem in large measure from environmental concerns, particularly concerns relating to reactor accidents and nuclear wastes. 

Radioactive waste management, 17 547-551 25 850-862 environmental concerns related to,... 

The committee considered the small amounts of PCBs that are suspected to be present in rocket motors and concluded that these amounts are far too small to pose an environmental concern. No data on PCBs were provided in any of the tests that the committee evaluated. Any small amounts of PCBs that may be present from rockets treated would end up in one of the solid waste streams and be at a concentration well below regulatory limits. 

Due to the capacity of deep wells to store injected waste for a long period of time, if the correct measures are taken in design, construction and operation, deep well injection can provide an effective and environmentally safe method of concentrate management. The major environmental concern for deep well injection is the potential for contamination of nearby aquifers, which may be used as a source of drinking water. Six pathways have been defined that describe the potential migration of concentrate that can cause contamination of aquifers (Shammas et al. 2009 United States Environmental Protection Agency 2002) ... 

In the 21st century, the chemical industry will be increasingly influenced by environmental concerns with respect to waste treatment. Consequently, one of the aims of green chemistry is the replacement of hazardous materials (solvents, reagents) by less hazardous substances [1-3]. In order to comply with the requirements of a sustainable development, modern state-of-the-art chemistry should comprise ... 

Waste generated (disposal cost, environmental concerns),... 

Issues environmental concerns, human safety, waste management, process inefficiency. 

In the improved synthesis of Ifetroban described above, environmental concerns due to special handling of copper bromide waste and hazards associated with hexa-methylene tetramine (HMT) on manufacturing scale led to further perfection of the synthesis. Mechanistic considerations suggested that an oxidized form of aminoamide B (Scheme 4) would eliminate the necessity for a late-stage copper-mediated oxidation. This was indeed accomplished. The cyclization-elimination sequence was initiated by a Lewis acid and completed by base-mediated elimination to afford the Ifetroban penultimate. In addition to eliminating the need for copper bromide and HMT, this modification helped to reduce the cost of the product by an additional 15%. 

Loose stone Crushed stone chips (top) in a variety of colors and textures—byproducts of the quarrying industry—make an acceptable alternative to quarried gravel or dredged gravel (bottom). A "scree garden" made with such chips or crushed brick waste is an effective way to display alpine plants, avoiding the environmental concerns caused by garden rock features (seep.134). 

Selection of a suitable method for silver removal depends on many factors what processes the company uses, what volume of wastes the company produces, what kind of training and technical knowledge the company s personnel has, whether the company wants to reuse the company s fixer or bleach-fix, how much the company wants to spend for recovery equipment, and what the environmental concerns are, such as how strict the effluent discharge limits are. Just considering these factors makes choosing a silver recovery method very much an individual decision for each company. 

It is obvious that such an assessment is formidable, technically difficult, and extremely expensive. Since an environmental source assessment study is required to characterize the total pollution potential of all waste streams, the sampling program must be more extensive than those conducted for the acquisition of process or control engineering data. Assessment sampling is more complete in that all waste streams are sampled and no attempt is made to limit sampling to a preselected number of process streams. The sampling is also more comprehensive in that all substances of potential environmental concern must be detectable above some minimum level of concern. These requiements of completeness and comprehensiveness call for a strategy of approach in which the philosophy and structure ensure maximum utilization of available resources. 

Environmental serious environmental concern (i.e. mercury, detergents) Recommendations use less toxic alternatives, dispose of hazardous wastes properly... 

Every year millions of cubic meters of ready-mixed concrete are returned for disposal in dump sites. There are now increasing environmental concerns and restrictions regulating the disposal of returned plastic concrete. In the last decade, environmental protection agencies in Europe and North America have classified both returned plastic concrete and truck wash water as hazardous waste. Consequently, the conventional methods of disposal in slurry tanks and landfill sites have become redundant, and disposal of plastic concrete is now a major problem for the ready-mixed concrete industry [102]. 

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