Chemical industry, pollution control

Since the beginning of the environmental movement in the 1960s many people have asked repeatedly if we better off environmentally today and, if so, can we do even more than we have done In some respects we see a bad side. The chemical industry still has a large amount of toxic chemical emissions. Pollution control is getting more expensive. On the brighter side. 

ViLBRANDT, F. C. and Dryden, C. E. (1959) Chemical Engineering Plant Design, 4th edn (McGraw-Hill). Walker, A. (1979) Law of Industrial Pollution Control (Godwin). 

This review summarizes the monopolar and BPM principles of operation. Moreover, this review presents shortly the main applications in chemical processing, pollution control, and resource recovery, and details the specific applications of electrodialysis with BPMs to food and bio-industries. 

Weber RC, Parker PA, Bowser M. 1981. Vapor pressure distribution of selected organic chemicals. Industrial Environmental Research Laboratory, Industrial Pollution Control Division, U.S. Environmental Protection Agency, Cincinnati, OH. EPA report no. EPA-600/2-81-021. 

Emission Standards. In order to have a nationwide basis for air pollution emission controls and to set a minimum emission limit, the EPA developed New Source Performance Standards (NSPS). The NSPS set specific poUutant emission limits or describe the best available control technology (BACT) that should be appUed at that source. The EPA has issued NSPS, which apply to new constmction as weU as to large modifications, for many different sources. Sources in the chemical industry include the foUowing. 

Fig. 25-3. Bubble concept. This pollution control concept places an imaginary bubble over an entire industrial plant, evaluating emissions from the facility as a whole instead of requiring control point-by-point on emission sources. Numbers represent emissions from individual sources, some of which can be fugitive sources, and from the entire industrial plant. Source Drawing courtesy of the Chemical Manufacturers Association.

Make no mistake about it - air pollution abatement, especially based upon end-of-pipe treatment technologies is expensive. Not too long ago the prevailing attitude among industry stakeholders was that air pollution control was simply a part of the cost of doing business, and that add-on costs associated with compliance simply had to be passed on to the consumer s purchase price for products. With the intensity of international competition in the chemical and allied industries, this philosophy simply does not cut it anymore. 

The suitability of gas absorption as a pollution control method is generally dependent on the following factors 1) availability of suitable solvent 2) required removal efficiency 3) pollutant concentration in the inlet vapor 4) capacity required for handling waste gas and, 5) recovery value of the pollutant(s) or the disposal cost of the unrecoverable solvent. Packed-bed scrubbers are typically used in the chemical, aluminum, coke and ferro-alloy, food and agriculture, and chromium electroplating industries. 

It is important to establish the volume of the process stream that is to be treated. There are companies that have not needed to buy pollution control equipment in the past. Their approach to eliminating pollution has been the more exhaust, the better. This is particularly true in the low margin industries. The more complex and high volume industries, e.g., the chemical industry, have normally been concerned about the air exhausted from their plant and have paid attention to the exhaust volume by process control. The industries that have not paid attention to exhaust volume are not sufficiently aware that when buying pollution control equipment the cost of that equipment is going to depend on two elements ... 

Formerly known as Chemical Manufacturers Association (CMA). A trade association of chemical manufacturers, representing more than 90 percent of the production for basic industrial chemicals in the US. Administers research in areas significant to chemical manufacturing such as air and water pollution control operates Chemical Transportation Emergency Center (CHEMTREC) to control and report chemical accidents. ACC is organized by industrial groups and also by issue groups that sen>e as coordinators and advocators in their fields of specializations. 

Public concerns about air quality led to the passage of the Clean Air Act in 1970 to amendments to that act in 1977 and 1990. The 1990 amendments contained seven separate titles covering different regula-toiy programs and include requirements to install more advanced pollution control equipment and make other changes in industrial operations to reduce emissions of air pollutants. The 1990 amendments address sulfur dioxide emissions and acid rain deposition, nitrous oxide emissions, ground-level ozone, carbon monoxide emissions, particulate emissions, tail pipe emissions, evaporative emissions, reformulated gasoline, clean-fueled vehicles and fleets, hazardous air pollutants, solid waste incineration, and accidental chemical releases. 

Although the major concern about the fate of organic pollntants in soil has been about pesticides in agricultural soils, other scenarios are also important. The disposal of wastes on land (e.g., at landfill sites) has raised questions about movement of pollutants contained in them into the air or neighboring rivers or water conrses. The presence of polychlorinated biphenyls (PCBs) or PAHs in snch wastes can be a significant source of pollution. Likewise, the disposal of some industrial wastes in landfill sites (e.g., by the chemical industry) raises questions about movement into air or water and needs to be carefully controlled and monitored. 

PARTIAL HISTORY OF POLLUTION AND POLLUTION CONTROL BY THE CHEMICAL INDUSTRY... 

Cost Analysis of Wuter Pollution Control An Annotated Bibliography, R5-73-017, Apr. 1973. Projected Wustewuter Treatment Costs in the Organic Chemical Industry, 12020 GND 07/71, July 1971. 

Three-phase slurry reactors are commonly used in fine-chemical industries for the catalytic hydrogenation of organic substrates to a variety of products and intermediates (1-2). The most common types of catalysts are precious metals such as Pt and Pd supported on powdered carbon supports (3). The behavior of the gas-liquid-sluny reactors is affected by a complex interplay of multiple variables including the temperature, pressure, stirring rates, feed composition, etc. (1-2,4). Often these types of reactors are operated away from the optimal conditions due to the difficulty in identifying and optimizing the critical variables involved in the process. This not only leads to lost productivity but also increases the cost of down stream processing (purification), and pollution control (undesired by-products). 

Stover EL, Kincannon DF. 1983. Biological treatability of specific organic compounds found in chemical industry wastewaters. J Water Pollut Control Fed 55 97-109. 

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