Solid waste, petroleum refinery

Raw material input to petroleum refineries is primarily crude oil however, petroleum refineries use and generate an enormous number of chemicals, many of which leave the facilities as discharges of air emissions, wastewater, or solid waste. Pollutants generated typically include VOCs, carbon monoxide (CO), sulfur oxides (SOJ, nitrogen oxides (NOJ, particulates, ammonia (NH3), hydrogen sulfide (HjS) metals, spent acids, and numerous toxic organic compounds. 

Petrochemical recovered oil. Organic chemical manufacturing facilities sometimes recover oil from their organic chemical industry operations. U.S. EPA excluded petrochemical recovered oil from the definition of solid waste when the facility inserts the material into the petroleum-refining process of an associated or adjacent petroleum refinery. Only petrochemical recovered oil that is hazardous because it exhibits the characteristic of ignitability or exhibits the toxicity characteristic for benzene (or both) is eligible for the exclusion. 

Spent caustic solutions from petroleum refining. Petrochemical refineries use caustics to remove acidic compounds such as mercaptans from liquid petroleum streams to reduce produced odor and corrosivity as well as to meet product sulfur specifications. Spent liquid treating caustics from petroleum refineries are excluded from the definition of solid waste if they are used as a feedstock in the manufacture of napthenic and cresylic acid products. U.S. EPA believes that spent caustic, when used in this manner, is a valuable commercial feedstock in the production of these particular products, and is therefore eligible for exclusion. 

The C-G process has been tested on the demonstration level by the U.S. Environmental Protection Agency (EPA). Studies have also been carried out for treating petroleum refinery wastes using this technology. It has been applied on a large scale to dry municipal sewage treatment solids. 

The technology is applicable to wastes that are contaminated with organic compounds and heavy metals and that have significant heat content, which should range from 3000 to 12,000 Btu per pound. The technology also treats soils contaminated with coal tar residues, petroleum refinery wastes, and municipal solid wastes, chemical waste, munitions, and rocket propellants. 

Filtration through granular materials to achieve removal of suspended matter and associated materials such as oil is an old concept. It is, however, receiving new attention in many areas in the petroleum industry where there is a concern for improving the quality of injection waters in secondary recovery operations and reducing the biochemical oxygen demand (BOD), oil, and suspended solids levels in refinery waste waters. 

It was previously mentioned that PDADMAC (Cat-Floe) was the first commercial flocculant approved for potable water [26]. Since then, PDADMAC has been continuously used for coagulation/flocculation both in potable water and waste water treatment. A good example of the performance of PDADMAC in the coagulation of colloidal solids is the reduction of turbidity in fresh water of 150 mg L 1 of Ca(OH)2. A reduction of 82% in turbidity is observed with the addition of only 2 mg L 1 of branched PDADMAC [217]. In addition, PDADMAC and copolymers of DADMAC are reported to be effective in the removal of hard-to-elimi-nate impurities in the water treatment industry. Emulsified impurities from streams of a petroleum refinery waste water and an automotive oily effluent water have been removed by the use of water soluble copolymers consisting essentially of DADMAC and small amounts of anionic acrylic monomers [89]. 

EPA. 1981a. Hazardous wastes from non-specific sources Petroleum refinery primary and secondary oil/water/solids separation sludges (F037, F038). U.S. Environmental Protection Agency. Code of Federal Regulations. 40 CFR 261.31. 

Table 12 shows the sources of solid wastes in a modem oil refinery. These data, provided by the American Petroleum Institute, are based on a typieal 200,000 barrels-per-day high-conversion refinery. A plant this size produces about 50,000 tons per year of solid waste and about 250,000 tons per year of waste water. As discussed above, all waste water must be purified before it leaves the plant. 

Cyclone Efficiency The methods described below for pressure drop and efficiency calculations were given by Zenz in Manual on Disposal of Refinery Wastes—Atmospheric Emissions, chap. 11 (1975), American Petroleum Institute Publ. 931 and improved by the Particulate Solid Research Inc. (PSRI), Chicago. 

Different types of petroleum can be used in different ways. Jet fuel differs from the gasoline that automobiles consume, for example. Refineries separate different petroleum products by heating petroleum to the point that heavy hydrocarbon molecules separate from lighter hydrocarbons so that each product can be used for a specific purpose. Refining reduces the waste associated with using limited supplies of more expensive petroleum products in cases in which a cheaper, more plentiful type of petroleum would suffice. Thus, tar or asphalt, the dense, nearly solid hydrocarbons, can be used for road surfaces and roofing materials, waxy substances called paraffins can be used to make candles and other products, and less dense, liquid hydrocarbons can be used for engine fuels. 

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