Subject volatile organic compounds

The two main sources of air pollutants that may be emitted from basic wastewater treatment plant operations are pulping condensates and bleach plant effluent. The pulping condensates may include total reduced sulfur (TRS) compounds as well as volatile organic compounds (VOCs) such as methanol. The primary pollutants of concern for the bleach plant effluent are chloroform and methanol. Any volatile compounds that could be released as air emissions from basic wastewater treatment plant operations are relatively minor and are generally not subject to specific regulation.65-66... 

PDA lipids embedded in silica fibers have been used for the detection of volatile organic compounds (Yoon et al. 2007). The fibers are prepared by subjecting a... 

Special process and product specifications have been set forth for companies in the chemical industry. Additionally, specific limits must be observed for pollutant or VOC (volatile organic compounds) emissions. Specific maximum allowable concentrations at workplaces must not be exceeded. Both the transport of chemicals and the recycling or disposal of chemical wastes are subject to particular requirements. Periodic hazard assessments - which in Germany, for example, are mandatory according to the Ordinance on Industrial Safety and Health (Betriebssicherheitsverordnung, BetrSichV) - are a must requirement in the chemical industry. To achieve a Continuous Improvement Process, product and process requirements must be identified, evaluated and monitored on a regular basis. 

Molhave, L., Jensen, J.G. and Larsen, S. (1991) Subjective reactions to volatile organic compounds as air pollutants. Atmospheric Environment, 25a (7), 1283-93. 

The decomposition of NO into its elements has not been realized yet. Another important issue of environmental catalysis is the removal of volatile organic compounds such as chlorohydrocarbons and dioxins. The simultaneous removal of NOx and SOx is another important subject for catalytic research. 

Ethylene is frequently formed when non-volatile organic compounds are subjected to destructive distillation, or when hydrocarbons are heated to such a temperature that they undergo decomposition. The ethylene found in coal gas and in carbureted water gas is produced in this way. Natural gas also contains a small percentage of this hydrocarbon. The luminosity of illuminating gas is due in part to the presence of ethylene, which is present in the gas to the extent of from four to five per cent. 

In this method of investigation, volatile organic compounds (e.g. fuels, organic solvents), which go over into the gas phase after the vapour pressure has reached equilibrium, are removed in gaseous form and subjected to analysis by gas chromatography. 

Adsorption has been playing an increasingly important role in environmental control. The sorbents being nsed in common industrial adsorption systems for the removals of SO2 and volatile organic compounds (VOCs) are qnite weU-estabUshed. The VOC removal systems often use activated carbon, polymeric resins, and hydrophobic zeolites, for both gas and aqueous systems. Activated carbon (and alkalized forms) and hydrophobic zeolites are used for SO2 removal. Lime injection is used for SO2 removal from hot gases. For NO removal, on the contiary, no suitable sorbents have been established. For this reason, selective sorbents for NO remain an active research area, and will be discussed. The search for CO2 sorbents is also of interest. The subject of CO2 sorbents has been discussed recently in an excellent review by Yong et al. (2002) and will not be covered here. 

Isocyanates are volatile organic compounds widely used in industry for products such as printing inks, adhesives, two-pack paints (particularly in vehicle body shops) and in the manufacture of plastics (polyurethane products). They are irritants and sensitizers. Inflammation of the nasal passages, the throat and bronchitis are typical reactions to many isocyanates. When a person becomes sensitized to an isocyanate, very small amounts of the substance often provoke a serious reaction similar to an extreme asthma attack. Isocyanates also present a health hazard to fire fighters. They are subject to a workplace exposure limit (WEL) and respiratory protective equipment should normally be worn. Two-pack polyurethane paints and varnishes are used in construction as surface coatings. 

Sources subject to the permit requirements generally include major sources that emit or have the potential to emit 100 tons per year of any regulated pollutant, plus stationary and area sources that emit or have potential to emit lesser specified amounts of listed hazardous air pollutants. However, in nonattainment areas, the permit requirements also include sources which emit as little as 50, 25, or 10 tons per year of volatile organic compounds (VOCs), depending on the severity of the region s nonattainment status. 

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