Environmental protection atmospheric emissions

With the ever increasing awareness of the need for environmental protection, the emission of solvent vapors and organic fumes into the atmosphere should be prevented by passing the exhaust through a proper scrubber. The solvent used for cleaning the reactor is usually consumed as part of the thinning solvent. Aqueous effluent should be properly treated before discharge. 

There always is a relation between fuel composition and that of hydrocarbon emissions to the atmosphere, whether it concerns hydrocarbon emissions from evaporative losses from the fuel system, or from exhaust gases. This is the reason that environmental protection regulations include monitoring the composition of motor and heating fuels. We will describe here the regulations already in existence and the work currently underway in this area with its possible effects on refining. 

Ethene and propene are produced as bulk feedstocks for the chemical (polymer) industry and therefore their purities are important parameters. In particular, H2S and COS are compounds which may not only cause corrosion problems in processing equipment, but also may have detrimental effects on the catalysts in use. Eurthermore, air pollution regulations issued by, among others, the US Environmental Protection Agency (EPA) require that most of the sulfur gases should be removed in order to minimize Sulfur emissions into the atmosphere. Therefore, these compounds have to be determined to the ppb level. 

Atmospheric emissions of sulphur dioxide are either measured or estimated at their source and are thus calculated on a provincial or state basis for both Canada and the United States (Figure 2). While much research and debate continues, computer-based simulation models can use this emission information to provide reasonable estimates of how sulphur dioxide and sulphate (the final oxidized form of sulphur dioxide) are transported, transformed, and deposited via atmospheric air masses to selected regions. Such "source-receptor" models are of varying complexity but all are evaluated on their ability to reproduce the measured pattern of sulphate deposition over a network of acid rain monitoring stations across United States and Canada. In a joint effort of the U.S. Environmental Protection Agency and the Canadian Atmospheric Environment Service, eleven linear-chemistry atmospheric models of sulphur deposition were evaluated using data from 1980. It was found that on an annual basis, all but three models were able to simulate the observed deposition patterns within the uncertainty limits of the observations (22). 

While numerous factors have been determined to impact CF14 emissions from rice cultivation, due to a general lack of field data, the United States Environmental Protection Agency (USEP A) currently uses a single emissions factor for all non-California-grown, primary rice crops [4]. Therefore, the purpose of this review is two-fold (i) discuss the factors known to control CH4 production in the soil and transport to the atmosphere from rice cultivation and (ii) summarize the historic and recent research conducted on CF14 emissions from rice production in the temperate United States. 

EPA. 1980a. Characterization of kerosene heater emissions inside two mobile homes. Contract no. EPA-600-D-90-115. Research Triangle Park, NC U.S. Environmental Protection Agency, Atmospheric Research and Exposure Assessment Laboratory, Harvard School of Public Health, Boston, MA. Document no. PB90-263013. 

Since the early 1970s, the European Union (EU) has been working to improve air quahty by controlling emissions of harmful substances into the atmosphere, improving fuel quahty, and by integrating environmental protection requirements into the transport and energy sectors. 

Industrial chloroprene emissions to the atmosphere reported to the United States Environmental Protection Agency for the Toxic Chemical Release Inventory totalled about 838 tonnes in 1987, 667 tonnes in 1991 and 446 tonnes in 1995 (United States National Library of Medicine, 1997b). 

The petroleum industry has taken the position that oil and gas production can and will be compatible with a high level of public health and environmental protection. The treating facilities at Jay are designed to achieve this goal, particularly regarding the emission of sulfur compounds into the atmosphere. 

Air quality is important from both a health and a safety perspective. In the USA, the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration set limits of exposure to over 2000 different chemicals or classes of respiratory irritants [11, 12], Many of the compounds that are monitored indoors are of similar interest to outdoor assessment, such as in the atmosphere and stratosphere. VOCs emitted from industrial operations are continuously monitored as required by US and local Environmental Protection Agencies. Power plants and waste incinerators are required to follow emission guidelines for harmful combustion gases, including CO and NO, as well as other combustion by-products, including polycyclic aromatic hydrocarbons, phenols, and hy-... 

Our goal is to gradually replace all coal and fossil fuel power plants with renewable energy ones, but while they exist (and probably will for most of this century), it is very important to reduce the damage they cause by optimizing their operation. In the United States, there are about 1000 coal preparation plants and coal-fired power plants. One key consideration in operating coalburning facilities is the control of C02 and sulfur dioxide (S02) emissions to the atmosphere. The characteristics of coal are monitored for environmental protection, quality assurance, and process control purposes. 

In September, 1998 the United States Environmental Protection Agency (EPA) issued a rale (known as the NOx SIP Call) that required 22 states and the District of Columbia to submit State Implementation Plans (SIP s). These SIP s would reduce emissions of nitrogen oxides (NOx) - compounds that react with other chemicals in the atmosphere to form ozone (or smog). EPA required these reductions after determining that NOx and ozone are transported by the wind to downwind states, which results in unhealthy air quality in the downwind states156. 

With respect to contributions of other mobile sources to the atmospheric burden of trace metals, very few data are available. The National Aeronautics and Space Administration in 1974 published calculated annual average ambient concentrations at or near airports of 49 trace elements attributable to aircraft most values were less than numbers. Of interest, however, are the estimates for the environmentally important metals, titanium, vanadium, and cadmium these were given as 24 ng/m , 0.12 ng/m and < 14 ng/m , respectively (56). EflForts to characterize aircraft emissions and to develop emissions factors by means of dynamometer tests are under way. One such experiment is being performed at Pratt and Whitney under contract to the Environmental Protection Agency results from this study should be available in mid-1978 (57). 

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