Emissions and Controls

The exhaust air from determent towers contains two types of contaminants  

Dust emissions are generated at scale hoppers, mixers, and crutch-ers during the batching and mixing of fine dry ingredients to form 

Dry cyclones are the primary collection equipment used to capture the detergent dust in the spray dryer exhaust and recycle it back to the crutcher. The dry cyclones can remove up to 90 percent by weight of the detergent product fines from the exhaust air. Fabric filters have been used after cyclones but have limited applicability, especially on efficient spray dryers, because of condensing water and organic aerosols binding the fabric filters [4, 21]. 

In addition to particulate emissions, volatile organic compounds (VOCs) may also be emitted when the slurry contains organic materials with low vapor pressures. The surfactants included in the slurry represent the origin of the VOCs. The vaporized organic materials condense in the tower exhaust air stream into droplets or particles. Paraffin alcohols and amides in the exhaust stream can result in highly visible plume that persists after the condensed water vapor plume has dissipated [4, 21]. Some of the VOCs identified in the organic emissions are hexane, methyl alcohol, 1,1,1-trichloroethane, perchloroethylene, benzene, and toluene [1-4]. 

A method for controlling visible emissions would be to remove by substitution the offending organic compounds from the slurry. 

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Sulfur Dioxide Emissions and Control. A substantial part of the sulfur dioxide in the atmosphere is the result of burning sulfur-containing fuel, notably coal, and smelting sulfide ores. Methods for controlling sulfur dioxide emissions have been reviewed (312—314) (see also Air POLLUTION CONTROL PffiTHODS COAL CONVERSION PROCESSES, CLEANING AND DESULFURIZATION EXHAUST CONTROL, INDUSTRIAL SULFURREMOVAL AND RECOVERY). 

N. A. Heinen and D. J. Patterson, Combustion Engine Economy, Emissions, and Controls, University of Michigan, Ann Arbor, Mich., Chapt. 5,1992. 

The chemical and metallurgical industries of the world are so varied and extensive that it is impossible to cover all of the processes, emissions, and controls in a single chapter. 

Air Pollution Emissions and Controls Inorganic Acid Manufacture... 

Nonferrous metallurgy is as varied as the ores and finished products. Almost every thermal, chemical, and physical process known to engineers is in use. The general classification scheme that follows gives an understanding of the emissions and control systems aluminum (primary and secondary), beryllium, copper (primary and secondary), lead (primary and secondary), mercury, zinc, alloys of nonferrous metals (primary and secondary), and other nonferrous metals. 

Many industries operated throughout the world do not fall into the previous categories. Some of these are universal, such as asphalt batching plants, whereas others are regional, such as bagasse-fired boilers. Each has its own emission and control problems and requires knowledgeable analysis and engineering. Some of the more widely used processes are examined in this section. 

A modem petroleum refinery is a complex system of chemical and physical operations. The cmde oil is first separated by distillahon into fractions such as gasoline, kerosene, and fuel oil. Some of the distillate fractions are converted to more valuable products by cracking, polymerization, or reforming. The products are treated to remove undesirable components, such as sulfur, and then blended to meet the final product specifications. A detailed analysis of the entire petroleum production process, including emissions and controls, is obviously well beyond the scope of this text. 

This section describes the major industrial processes within the petroleum refining industry, ineluding the materials and equipment used, and the processes employed. The section is necessary for an understanding of the interrelationships between the industrial processes, the types of air emissions, and control and pollution prevention approaehes. Deseriptions of eommonly used production processes, assoeiated raw materials, by-produets produeed are first deseribed. Petroleum refining is the physieal, thermal, and chemical separation of erude oil into its major distillation fraetions, which are then further proeessed through a series of separation and eonversion steps into finished petroleum produets. The primary products of the industry fall into three major categories ... 

CAC is divided into two phases as follows "command", which sets a standard based on the maximum level of permissible emissions, and "control", which monitors and enforces the standard. 

Yagi K, Tsuruta H, Minami K, Chairog P, Cholitkul W. 1994. Methane emission from Japanese and Thai paddy soils. In Minami K, Mosier AR, Sass RL, eds. CH4 andN20 Global Emissions and Controls from Rice Fields and Other Agricultural and Industrial Sources. Tsukuba National Institute for Agroenvironmental Sciences, 41-53. 

Chapter 17 ECC Emission Reduction Technologies through Consent Decree Implementation FCC NO Emissions and Controls... 

The U.S. Environmental Protection Agency s Control Technology Center recognizes the need for data describing the air quality impacts of two of these disposal options the controlled burning of tires to recover its fuel value and pyrolysis for fuel and carbon black. The purpose of this report is to summarize available air emissions and control data and information on tire pyrolysis and burning tires for fuel. 

Investigations of Fugitive Dust Sources, Emissions, and Controls, pre-... 

Gibbs MJ, Wasson J, Magee T, et al. 1992. Study of emissions and control of stratospheric ozone-depleting compounds in California. ICF Consulting Association. Inc., Universal City. CA. USA. 305 pp. NTIS No. PB93-160752. 

Oonk, H., Kroeze, C. (1999). Nitrous oxide emissions and control. In R. A. Meyers (Ed.). Encyclopedia of Environmental Pollution and Cleanup. The Wiley, 1055-1069. 

Nitrogen Oxides Emissions and Controls, EPA/600/7—88/015, U.S. Environmental Protection Agency, Research Triangle Park, NC, 1988. 

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