Control chemical industry

Technology for Pollution Control, Chemical Industries Series. (M.L. Occelli and R.R. Chianelli, Eds.), Vol. 67, p. 95. Marcel Dekker, New York, 1996. 

Enclosed agitated filters are useful when volatile solvents are in use or when the solvent gives off toxic vapor or fume. Another significant advantage is that their operation does not require any manual labor. Control can be manual or automatic, usually by timers or by specific measurements of the product. Most filters are made of mild steel, with the exposed surfaces protected by lead, tile, mbber lining, or by coating or spraying with other substances as necessary. Filtration areas up to 10 m are available and the maximum cake thickness is 1 m. Apphcations are mainly in the chemical industry for the recovery of solvents. 

Plant Fireproofing. There is a growing practice in the chemical industry of locating principal equipment out of doors and to enclose only a control room where all instmments and control equipment are centered. The control room should be resistant to potential explosion, fire, and toxicity ha2ards of processes in the vicinity. Prompt and ordedy shutdown of processes following a serious incident is essential in order to minimise personnel-injury and property-loss ha2ards (65,66). 

Process Plant Ha ard and Control Building Design, Chemical Industries Association (U.K.), 1979. 

The effluent standards require two levels of treatment best practicable control technology (BPCT) and best available control technology (BACT). New standards covering additional industries are stiU being issued. Of special concern to the chemical industry are the following Hsted categories ... 

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. 

Toxic Substances Control Act. EPA regulates the manufacture, use, and exposure to ha2ardous or toxic chemicals under a number of laws. Eor the chemical industry, the law of prime concern is the Toxic Substance Control Act (TSCA) (10), which was passed by the U.S. Congress in 1976. The two main goals of TSCA are acquisition of sufficient information to identify and evaluate potential ha2ards from chemical substances, and regulation of the production, use, distribution, and disposal of these substances. 

Corrosion-resistant fabrication must be used in the equipment that comes in contact with many chemical industry discharges (see Corrosion and corrosion control). 

As in the case of highways, considerable contention results from public maintenance of the inland waterways for recreation, flood control, and other purposes, as well as for the transportation of barges and other freight-carrying vessels. Because barge transportation of chemicals is considered essential to economical distribution, governmental toUs assessed for such maintenance ate of critical interest to the chemicals industry. 

Oxygen Control. To meet industrial standards for both oxygen content and the allowable metal oxide levels in feed water, nearly complete oxygen removal is required. This can be accompHshed only by efficient mechanical deaeration supplemented by an effective and properly controlled chemical oxygen scavenger. 

Asahi Chemical Industries uses this process to coat N—P—K fertilizers, marketed as Long, High Control, and Nutricote. 

The chemical industry was the first to utilize catalytic oxidation extensively for emission control, building units capable of treating up to 50 m /s (100,000 scfm) of exhaust gas containing VOCs. Catalytic systems accounted for roughly one-fourth of the 200 million market for VOC control systems in 1992, and over one thousand catalytic oxidization devices were in place by the end of that year (5). 

CIA 1990. A Approach to the Categorization of Process Plant Hazard and Control Building Design. Prepared by Working Group 3 of the Major Hazards Steering Group. Issued by the Safety Committee of the Chemical Industry Safety and Health Council of the Chemical Industries Association, Eondon. 

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