Coal, distillation Combustion

Sulphur oxides G Sulphur dioxide Sulphur trioxide Coal distillation Combustion of coal and heavy fuel oil Detergents (sulphonation of alkyl benzenes) Electricity generation... 

Atmospheric particulate emissions can be reduced by choosing cleaner fuels. Natural gas used as fuel emits negligible amounts of particulate matter. Oil-based processes also emit significantly fewer particulates than coal-fired combustion processes. Low-ash fossil fuels contain less noncombustible, ash-forming mineral matter and thus generate lower levels of particulate emissions. Lighter distillate oil-based combustion results in lower levels of particulate emissions than heavier residual oils. However, the choice of fuel is usually influenced by economic as well as environmental considerations. 

Gob Fires in Coal Mines. Under this name are known spontaneous combustions in coal mines arising in waste (gob) piles. When the area had been partially or completely sealed off, the heat could distil combustible gases from residual coal in the vicinity and create an expl mixt if the available oxygen had nor been depleted at too fast a rate. An odor know as "gob stink sometimes served as a warning to workers of the existence of one of these Gres... 

Table IV gives the properties of the SRC-II fuel oil compared to a low-sulfur residual oil utilized in a recent combustion test. The SRC-II fuel oil is a distillate product with a nominal boiling range of 350-900°F, a viscosity of 40 Saybolt seconds at 100°F and a pour point below -20°F. Thus, it is readily pumpable at all temperatures normally encountered in transportation of the fuel oil. The fuel oil has a very low content of ash and sediment as well as a low Conradson carbon residue. These characteristics are favorable from the standpoint of particulate emissions during combustion. Tests of compatibility with typical petroleum fuel oils and on stability of the coal distillates over time have not revealed any unusual characteristics that would preclude utilization of these coal-derived fuels in conventional boiler applications.

Large-scale testing in a utility boiler of SRC-II coal distillates from the Ft. Lewis pilot plant indicates complete acceptability in combustion performance and emissions. Testing and development for other applications of SRC-II produced coal liquids is planned, including combustion turbines and medium speed diesels. 

A black, viscous liquid (or semi-solid), naphthalene-like odor, sharp burning taste obtained by the destructive distillation of bituminous coal, as in coke ovens 1 ton of coal yields 8.8 gallons of coal tar. Combustible. Specific gravity 1.18-1.23 (66/60 °F). Soluble in ether, benzene, carbon disulfide, chloroform partially soluble in alcohol, acetone, methanol, and benzene only slightly soluble in water. 

ORIGIN/INDUSTRY SOURCES/USES from petroleum refining, shale oil processing, coal tar distilling, combustion of tobacco used to manufacture dyes, plastics insecticides and fungicide manufacturing constituent in asphalt... 

EXPOSURE ROUTES most probably is occupational exposure dermal contact inhalation natural fires petroleum refining coal tar distillation combustion of wood, coal, oil, propane, gasoline, and diesel fuels industrial effluents municipal wastewater treatment facilities waste incinerators smoked and barbecued foods contaminated drinking water supplies recreation activities at contaminated waterways... 

Large numbers of polynuclear aromatic compounds occur in the tar from hard coal distillation, in products of pyrolysis and in a variety of residues from combustion. These compounds have been separated by TLC on silica gel [46, 47], alumina [46, 59] and acetyl-cellulose [1, 78]. 

Carbonization. Next to combustion, carbonization represents one of the largest uses of coal (2,24—26). Carbonization is essentially a process for the production of a carbonaceous residue by thermal decomposition, accompanied by simultaneous removal of distillate, of organic substances. 

Fixed orSlowlj M-OvingFeds. For fuel-bed burning on a grate, a distillation effect occurs. The result is that hquid components which are formed volatilize before combustion temperatures are reached cracking may also occur. The ignition of coal in a bed is almost entirely by radiation from hot refractory arches and from the flame burning of volatiles. In fixed beds, the radiant heat above the bed can only penetrate a short distance into the bed. 

By the middle of the nineteenth century it was realized, both in England and in the United States, that kerosene, or coal oil, distilled from coal, could produce a luminous combustion flame. Commercialization was rapid. By the time of the U.S. Civil War, /yr (23,000 gal/yr) of lamp oil was... 

Occurrence. Carbon monoxide is a product of incomplete combustion and is not likely to result where a flame bums in an abundant air supply, yet may result when a flame touches a cooler surface than the ignition temperature of the gas. Gas or coal heaters in the home and gas space heaters in industry have been frequent sources of carbon monoxide poisoning when not provided with effective vents. Gas heaters, though properly adjusted when installed, may become hazardous sources of carbon monoxide if maintained improperly. Automobile exhaust gas is perhaps the most familiar source of carbon monoxide exposure. The manufacture and use of synthesis gas, calcium carbide manufacture, distillation of coal or wood, combustion operations, heat treatment of metals, fire fighting, mining, and cigarette smoking represent additional sources of carbon monoxide exposure (105—107). 

Contaminants in fuels, especially alkali-metal ions, vanadium, and sulfur compounds, tend to react in the combustion zone to form molten fluxes which dissolve the protective oxide film on stainless steels, allowing oxidation to proceed at a rapid rate. This problem is becoming more common as the high cost and short supply of natural gas and distillate fuel oils force increased usage of residual fuel oils and coal. 

Liquid fuels for use in internal-combustion engines are extracted and refined from crude oil, with diesel fuels being part of the middle distillate or kerosene fraction. Kerosene was initially derived from coal pyrolysis. The initial main use of this type of distillate was for the kerosene lamp, which had replaced lamps based on whale oil. 

The Industrial Revolution came hand-in-hand with the use of fossil fuels. Although coal had been used for heating and in metallurgy since at least the thirteenth century, it was not until the invention and refinement of the steam engine that coal consumption increased greatly. By the middle of the nineteenth century, work done by machines exceeded the work done by animal power. While steam engines were mainly fueled by coal, the advent of the internal combustion engine required a volatile fuel, and petroleum distillates are perfectly suited for this purpose. 

Methanol also seems to biodegrade quickly when spilled and it dissolves and dilutes rapidly in water. It has been recommended as an alternative fuel by the EPA and the DOE, partly because of reduced urban air pollutant emissions compared to gasoline. Most methanol-fueled vehicles use a blend of 85% methanol and 15% gasoline called M85. Building a methanol infrastructure would not be as difficult as converting to hydrogen. While methanol can be produced from natural gas, it can also be distilled from coal or even biomass. In the 1980s, methanol was popular for a brief time as an internal-combustion fuel and President Bush even discussed this in a 1989 speech. 

Source Detected in groundwater beneath a former coal gasification plant in Seattle, WA at a concentration of 180 g/L (ASTR, 1995). Acenaphthene is present in tobacco smoke, asphalt, combustion of aromatic fuels containing pyridine (quoted, Verschueren, 1983). Acenaphthene was detected in asphalt fumes at an average concentration of 18.65 ng/m (Wang et al., 2001). Present in diesel fuel and corresponding aqueous phase (distilled water) at concentrations of 100 to 600 mg/L and 4 to 14 g/L, respectively (Lee et al, 1992). 

Toxicology. Epidemiological evidence suggests that workers intimately exposed to the products of combustion or distillation of bituminous coal are at increased risk of cancer at many sites, including lungs, kidney, and skin. The chemical composition and particle size distribution of coal tar pitch volatiles (CTPV) from different sources are significant variables in determining toxicity. ... 

Gas, Coal, Acedg to Riegel (Ref), coal gas is a combustible gas obtd by distilling bituminous coal in small horizontal and vertical retorts. The primary object of distn of coal is gas. As coal gas is high in illumi-nants (benzene and ethylene), it can serve as illuminating gas... 

Gas, Illuminating. A gas used for production of light. It is prepd by distillation of bituminous coal in small horizontal or vertical retorts. Other combustible gases may be used for this purpose, provided they contain sufficient amts of ilium in ants, such as benzene or ethylene. Some illuminating gases contain "natural gas" mixed with other gases (See also under Gas, Coal)... 

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