Processing asphalt

Asphalt processing and asphalt roofing manufacture (Subpart UU)... 

Metal Coil Surface Coating Asphalt Processing and Asphalt Roofing Manufacture... 

Phosphate rock plants" Rotogravure printing Large appliance surface coating Meted coil surface coating Asphalt processing and roofing manufacture... 

Air entrainment and foaming in hydrocarbon liquids can cause operational problems with high-speed machinery in physical-chemical processes such as petroleum production, distillation, cracking, coking, and asphalt processing. 

Gilsonite. A pure form of asphalt processed into powdered form for use as the enclosing insulating mass around pipes or tanks underground. 

Standards of Performance for Asphalt Processing and Asphalt Roofing Manufacture Standards of Performance for Equipment Leaks of VOC in the Synthetic Organic Chemicals Manufacturing Industry... 

National Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing National Emission Standards for Hazardous Air Pollutants Asphalt Processing and Asphalt Roofing Manufacturing... 

SOLVAHL A petroleum de-asphalting process developed by IFP and now licensed by Axens. See ASVAHL. 

Tutagaki SK. 1983. Petroleum refinery workers exposure to PAHs at fluid catalytic cracker, coker, and asphalt processing units. Cincinnati, OH National Institute for Occupational Safety and Health, NIOSH publ. no. 83-111. 

The versatile characteristics of sand-sulfur-asphalt mixes suggest a number of diverse possible uses for these materials (3). Some of these have already been investigated while others will be examined in the future. Various features of the sand-sulfur-asphalt process are covered by patents and patent applications in a number of countries. This process will be made available to industry under license when development work has been successfully completed. 

Determination of particulate matter emissions from asphalt processing and asphalt roofing indushy Determination of nonsulfuric acid particulate matter emissions from stationary sources (reserved)... 

Such synthetic bitumen lends itself to a variety of modifications and uses. Steam distillation under vacuum, a universal practice in asphalt processing, would remove volatiles and the nonvolatile residue could be air-blown to asphalt. The residue from distillation, if pitch-like, could be fluted with a nonvolatile oil and excessive asphaltene constituents could be precipitated by solvent refining. 

In various asphalt processing methods, the rheological properties of the compounded asphalt are of primary importance. One invention shows how, by blending different fractions of crude oil, the processing properties can be optimized for pavement applications. In another recent invention,solvent-free polyurethane was compounded with asphalt. Such products have always contained substantial amounts of solvents to reduce viscosity to the level that allows the material to be cold applied with simple techniques. Using organoclay as compatibilizer for polyurethane and asphalt and a suitable plasticizer, elimination of solvent becomes possible. In addition to environmental safety, these products can be used safely on substrates which would otherwise be affected by solvents the formulation (e.g., polystyrene insulation boards). This is one example which shows that the benefits of solvent free systems go beyond the elimination of air pollutants. 

Volatilization and thermal destmction are the primary methods of remediation of lighter hydrocarbons in the hot-mix asphalt process. Solidification/stabilization is the secondary method of remediation. Heavier hydrocarbons remaining in the soil after the drying step are encapsulated within the asphalt/aggregate matrix. 

As far as the authors are aware the only other extraction process with a near-critical solvent to come into use in the period 1924-1960 was the Solexol process for the purification of vegetable and fish oils using compressed propane [60-64]. (The underlying principles for this process are identical to those for the propane de-asphalting process.) In 1952 it appears that about five commercial Solexol plants were in service [45]. The present position is not quite so clear [65]. 

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