Solid effluents

Fatal accident rate Lost-time injury rate Capital cost of accidents Number of plant/community evacuations Cost of business interruption Cost of workers compensation claims Number of hazardous material spills (in excess of a threshold) Tonnage of hazardous material spilled Tonnage of air, water, liquid and solid effluent Tonnage of polluting materials released into the environment Employee exposure monitoring Number of work related sickness claims Number of regulatory citations and fines Ecological impact of operations (loss or restoration of biodiversity, species, habitats)... 

Tonnage of air emissions, water emissions and liquid and solid effluent and tonnage of hazardous materials released into the environment. These two measures are related to one another. However, the first measure relates the total effluent, including nonpolluting materials. The second measure looks only at the tonnage of hazardous materials contained in the total effluent. Both measures can be important indicators. For example, for solid waste it is important to know the total volume of material for disposal and different upstream treatment techniques may affect the total volume. However, for ozone depleting chemicals, only the quantity of these gases is important and other components such as water vapor may be irrelevant. 

Solid effluents arising from metallurgical operations occur principally in two forms fine particulate solids or dusts, and solid wastes. As an example, blast furnace gas may contain up to 170 kg of dust per ton of pig iron produced. Suitable methods must be devised for processing the solid effluents for two reasons (i) to prevent pollution of the environment and (ii) to recover their valuable content, if any. As far as the latter is concerned, reference may be drawn, as an example, to the recovery of rhenium from the exit gas from molybdenite roasting in a multiple-hearth furnace. 

The liquid and solid effluents are well characterized. As the ACW I Committee noted in its original and supplemental reports, the gaseous process emissions will have to be characterized for health risk assessments and environmental risk assessments required by EPA guidelines (NRC, 1999, 2000a). These results, along with the results of analyses of metals emissions (including chromium VI), can be used to assess the environmental impact of a facility through accepted risk-assessment methods (EPA, 1998). 

Radioactive waste management involves the treatment, storage, and disposal of liquid, airborne, and solid effluents from the nuclear industry s operations, along with those from other activities that employ the radioactive products. Its strategy involves four approaches limit generation, delay and decay, concentrate and contain, and dilute and disperse. Combinations of all four of these usually are employed to manage each waste stream.39... 

Oil Shale and Solvent-Refined Coal Feedstocks and Solid Effluents. 

While talking about clean technologies, one may also cite the case of replacement of the hydroxy (-OH) group by a methoxy (-OCH3) group by using dimethyl sulfate as in the case of pctra-cresyl methyl ether from p-cresol. Use of methanol and a suitable catalyst, say zeolites, should be established. This would reduce much of environment-related problems, by eliminating disposal of solid effluent such as sodium sulfate. 

The production of synthetic liquid hydrocarbons from natural gas has a low environmental impact. All waste water leaving the complex would first be treated to allow discharge into a river. As a general principle, the re-use of process water and condensate would be designed to minimize discharge of waste water. The only non-solid effluents would be clean water produced in the process and sulphur-free flue gases. As for solid waste, spent catalyst can conceivably be returned to the catalyst manufacturer for metals recovery. 

In addition to the difficult matrix in acid mine drainage (low pH and high dissolved solids), effluent from the wetlands treatment cells contained high levels of dissolved organic compounds. These samples were impossible to filter through a 0.45 micrometer filter. Use of RAS analyses for these samples is not appropriate. In some cases, even a SAS cannot be specified without independent evaluation of appropriate methods. 

Environmental considerations. By-products often appear as pollutants discharged from the manufacturing pleuit ets constituents of gaseous, liquid or solid effluents. The pollution of the environment by chemical effluents is of increasing concern and further legal constraints and limits are likely to be imposed. Phenolic impurities, commonly found ets by-products of aromatic nitration, are particularly harmful in the damage they cause in water courses because of their high toxicity. 

The disadvantages of wet scrubbers are that they produce a visible steam plume, and liquid and solid effluents, which can cause disposal problems. Where low sulfur fuels are used, the effluent may contain calcium hydroxide which in one installation has been found to give pH values as high as 11.3 the sludge is also alkaline and may present disposal problems. Where high sulfur fuels are used, the effluent contains dissolved salts, mainly calcium sulfate and possibly calcium bisulfite. The latter could lead to a biological oxygen demand. 

Despite the problems encountered during testing, adequate destruction of CWC Schedule 2 compounds was demonstrated for the gaseous, liquid, and solid effluents from the TW-SCWO system. The concentrations of many chemical constituents in the gaseous effluent were highly variable. 

Coal-based processes involved in combustion and conversion facilities release gaseous and liquid effluents as well as solid effluents deleterious to the environment and human health. The preference can be made from the following alternatives (Clark et al., 1977) ... 

Because /i-heptane is less dense than /-propanol, the solid floats on the liquid. We therefore show the solid effluent leaving the top of the separator. 

The only solid effluent is spent catalyst which will be recycled to recover the metallic components. 

Environmental conditions liquid effluent solid effluent gaseous effluent noise... 

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