Emissions from industrial chemical plants

The most widespread and persistent urban pollution problem is ozone. The causes of this and the lesser problem of CO and PMjq pollution in our urban areas are largely due to the diversity and number of urban air pollution sources. One component of urban smog, hydrocarbons, comes from automobile emissions, petroleum refineries, chemical plants, dry cleaners, gasoline stations, house painting, and printing shops. Another key component, nitrogen oxides, comes from the combustion of fuel for transportation, utilities, and industries. 

Soils and waters affected by emissions from smelters, power plants. Soils and waters affected by mining wastes and by-products. Some playa lake sediments. Soils and dusts derived from naturally As-enriched rocks and sediments. Waters that have leached As from As-rich rocks, soils, and sediments. Pesticides, other industrial chemicals. By-products or wastes from chemical manufacturing or other industrial processes. 

The pollution with dust is caused by emissions from industrial plants and traffic, as well as by high emissions from natural sources of dust. The main emission sources of nitrogen oxides are mainly the mobile ones such as motor vehicles. The relatively high level of pollution by ozone is determined by photo-chemical reactions in the atmosphere under the influence of solar radiation and the high level of ozone precursor compounds. 

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.

The harmful effects of industrial emissions are not confined to the workers but extend beyond the plant boundary line. Chemically-induced diseases among workers exposed to industrial chemicals are a warning sign of the risks to which a larger population is also being exposed usually the chemical hazards are in principle similar in the occupational and general environment. However, occasionally environmental exposures can be qualitatively different from the occupational environment and may also cause deleterious health effects in the general population. 

The BiodeNOx process is a novel process concept to reduce NO emissions from flue gases of stationary sources like power plants and other industrial activities [1]. The concept combines a wet chemicd absorption process with a novel biotechnological regeneration method. In the wet chemical absorption step, flue gas components are absorbed into an aqueous solution of Fe"(EDTA) (EDTA= ethylme-diamino-tetraacetic acid). The following reactions take place ... 

The full potential use of biofilters for cleaning air from livestock buildings, treatment plants and emissions from chemical industry have yet to be exploited. The papers presented produced proof of the efficiency of these filters to remove odour emissions from odorous air streams. Research and Development work is required to reduce the costs of construction and to find materials to which will not deteriorate quickly. Work is required to reduce the large surface areas required at present. 

Considering the composition of petroleum and petroleum products (Speight, 1994, 1999), it is not surprising that petroleum and petroleum-derived chemicals are environmental pollutants (Loeher, 1992 Olschewsky and Megna, 1992). The world s economy is highly dependent on petroleum for energy production, and widespread use has led to enormous releases to the environment of petroleum, petroleum products, exhaust from internal combustion engines, emissions from oil-fired power plants, and industrial emissions where fuel oil is employed. 

In 1989 the Environmental Protection Agency ordered a 90% reduction of industrial benzene emissions over the next several years at a cost of 1 billion. The new standard leaves more than 99% of the exposed population with risks of cancer less than one in 1 million, or one cancer case in the U.S. every 10 years. Hardest hit are the iron and steel industry, where benzene emissions from coke by-product recovery plants are large. Chemical industry plants have already reduced their benzene emissions 98%. EPA estimates that the 390,000 or so gasoline service stations in the U.S. will all have to be fitted with devices to eliminate the escape vapors when fuel is put into underground storage tanks. 

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