Straight-run asphalt

Straight-run asphalts Straight run naphthas Strain gauges Strainmaster S. strain NRRL 15496 Stratosphere Stratospheric ozone... 

Straight Run Asphalt. In cmde-oil refining, the crude oil at 340—400°C is injected into a fractionating column (5,6,19,20). The lighter fractions are separated as overhead products and the residuum is straight-reduced asphalt. 

Figure 4. Comparison of Air Blown and Straight Run Asphalts from the Same Crude...

Straight-run asphalt the asphalt (q.v.) produced by the distillation of asphaltic crude oil. 

Many investigations of relationships between composition and properties take into account only the concentration of the asphaltenes, independent of any quality criterion. However, a distinction should be made between the asphaltenes that occur in straight-run asphalts and those that occur in blown asphalts. Because asphaltenes are a solubility class rather than a distinct chemical class vast differences occur in the makeup of this fraction when it is produced by different processes. 

If straight-run asphalts are reduced to a hardness below 300 penetration (30 mm), they are termed asphalt cements. For hot-mix paving, either the AC-10 viscosity grade or the next harder AC-20 grade is commonly specified. 

Dibutyl Phthalate Dioctyl Phthalate Arsenic Disulfide Arsenic Disulfide Arsenic Disulfide Cleic Acid Arsenic Disulfide Nitrogen Tetroxide 4-Chloro-O-Toluidine Asphalt Blending Stock Oil Rosin Resorcinol Resorcinol Salicylic Acid Oil Resin Oil Rosin Sodium Thiocyanate Asphalt Blend Stock Straight Run Asphalt Oil Resin... 

Asphalt can be generally classified as natural or artificial. Natural asphalts include bituminous materials laid down in natural deposits, such as those in Trinidad, and as gilsonites and grahamite bitumens, which are completely soluble in carbon disulfide. Artificial asphalt includes mainly petroleum-derived asphalts and, to a lesser extent, coal tar, water-gas tars, and their pitches. There are types of asphalt products obtained from straight-run asphalt (refined naphtha-based crude oils) hot, cutback, and emulsion asphalt. 

Cutback asphalts comprise four types in the US (I-IV) and three types (I-III) in Canada. The No. I type consists of straight-run asphalt, and solvent and either a small amount of fiber or none the No. II type is obtained by adding a large amount of fibers and filler to the asphalt cut with solvent and No. Ill is primer-type in solution without any fillers or fibers. 

Two distinct types of material are found in cracked fuel oil (1) scarcely decomposed straight-run asphaltic material derived from residual feedstocks, and (2) condensation or polymerization materials derived from reactive fragments produced during cracking. In addition, the straight-run asphaltic material is frequently exposed to the mild operation known as viscosity breaking (either in a separate coil or as part of the recirculation in a black-oil coil). The viscosities and gravities of these com-... 

ASPHALT BLENDING STOCK (STRAIGHT RUN RESIDUE) Petroleum Asphalt, Petroleum Pitch, Road Binder NL 0 1 0 ... 

Asphalt (qv) is prepared from petroleum and often resembles bitumen. When asphalt is produced simply by distillation of an asphaltic crude, the product can be referred to as residual asphalt or straight-run petroleum asphalt. If the asphalt is prepared by solvent extraction of residua or by light hydrocarbon (propane) precipitation, or if blown or otherwise treated, the term should be modified accordingly to qualify the product, eg, propane asphalt. 

Refining begins by distillation of crude oil into three principal cuts straight-run gasoline fbp 30-200°C), kerosene (bp 175-300 C), and gas oil (bp 275-400°C). Finally, distillation under reduced pressure gives lubricating oils and waxes, and leaves an undistillable tarry residue of asphalt. 

Straight-run fuel oil fractions from the same crude oil normally are stable and mutually compatible. However, fuel oil produced from the thermal cracking and visbreaking operations may be stable by themselves but can be unstable or incompatible if blended with straight-run fuels and vice versa. Furthermore, asphaltic deposition may result from the mixing of (distillate and residual) fuel oils of different origin and treatment, each of which... 

Hydrotreating is being employed extensively in the petroleum industry for processing a variety of feedstocks. Both straight-run and cracked petroleum products such as naphthas, kerosenes, middle distillates, gas oils (atmospheric and heavy vacuum types), cycle stocks, residues, asphalts, crudes, and shale oils may be so treated. The process primarily is employed as a pretreat previous to catalytic reforming or catal3d ic cracking. 

A number of fractions (components) are obtained from the distillation of petroleum. Distillation is defined as the separation of the various fractions in a mixture by individual boiling points. Hydrocarbon fractions obtained from petroleum include straight-run gasoline, kerosene, heating oil, diesel, jet fuel, lubricating oil, paraffin wax, asphalt, and tar (Figure 13-10). Additional processes can be applied to these different fractions to create other products. 

Compound Name Arsenic Acid Asphalt Blend Stock Straight Run Residue Oils Edible Safflower Diphenylmethanediisocy anate (MDl)... 

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