Asphalt Specification

Remembering that the properties of residua vary with cut-point (Table 2), ie, the vol % of the cmde oil (Fig. 13) helps the refiner produce asphalt of a specific type or property. There are several properties that are usually controlled in asphalt specifications ... 

For asphalt operation, experimental data is necessary, relating asphalt penetration to residual volume. Using this information, distillate volume can be readily established. Units have been built to make asphalt over the penetration range of 85 down to 10 (approximately 7 to 4 degrees API). The asphalt specifications will most often be set by the owner, and it may be necessary to design for more than one grade of product. 

The products could be classified as a function of various criteria physical properties (in particular, volatility), the way they are created (primary distillation or conversion). Nevertheless, the classification most relevant to this discussion is linked to the end product use LPG, premium gasoline, kerosene and diesel oil, medium and heavy fuels, specialty products like solvents, lubricants, and asphalts. Indeed, the product specifications are generally related to the end use. Traditionally, they have to do with specific properties octane number for premium gasoline, cetane number for diesel oil as well as overall physical properties such as density, distillation curves and viscosity. 

In general, when the product is a fraction from cmde oil that includes a large number of individual hydrocarbons, the fraction is classified as a refined product. Examples of refined products are gasoline, diesel fuel, heating oils, lubricants, waxes, asphalt, and coke. In contrast, when the product is limited to, perhaps, one or two specific hydrocarbons of high purity, the fraction is classified as a petrochemical product. Examples of petrochemicals are ethylene (qv), propylene (qv), benzene (qv), toluene, and xylene (see Btx processing). 

Asphalt. This is a distillatioa residuum that can also be produced by propane deasphalting (Fig. 7) (33) and thereafter modified to meet specifications. For example, asphalt (qv) can be made softer by blending hard asphalt with the extract obtained ia the solveat treatmeat of lubricatiag oils. Oa the other hand, soft asphalts can be converted iato harder asphalts by oxidation (air blowiag). 

Asphalt-Rubber Systems (Warwick, Rhode Island) markets, designs, and develops specifications for asphalt—mbber paving projects for highways and streets. The company has paved 48 km of highway in Worcester, Massachusetts. Some sections of the road paved with asphalt—mbber membranes are more resilient than surfaces without asphalt—mbber (16). 

Standard Specification for Asphalt Shingles (Organic Felt) Surfaced with Mineral Granules Standard Specification for Class A Asphalt Shingles Surfaced with Mineral Granules... 

Standard Specification for Asphalt Shingles Made from Glass Felt and Surfaced with Mineral Granules Standard Test Method for Wind Resistance of Asphalt Shingles (Fan-Induced Method)... 

Y)224 Standard Specification for Smooth-Surfaced Asphalt RoU Roofing (Organic Felt)... 

Sheet form, 914 mm (36 in.) in width, or widths agreed upon by purchaser and suppHer, composed of asphalt-saturated organic felt with approximately half the width of weather side coated with asphalt and surfaced with mineral granules, for use as cap sheet in constmction of BUR. Materials covered by this specification, in minimum mass per unit area, are Type I, 1806 g/m (37.0 lb/100 fU) Type II, 2260 g/m (46.3 lb/100 fU) Type III, 1733 g/m (35.5 lb/100 fU) and Type IV, 2090 g/m (42.8 lb/100 fU). 

Standard Specification for Asphalt-Saturated Organic Felt Used in Roofing and Waterproofing Standard Specification for Asphalt-Saturated Organic Felt Shingle Undedayment Used in Roofing... 

With or without perforations, may be used with asphalts conforming to Specification D312 requirements in constmction of BUR, and Specification D449 requirements in membrane system of waterproofing. Felts covered by this specification are Type I (No. 15 asphalt felt) and Type II (No. 30 asphalt felt). 

Shingle as undedayment with asphalt shingles. Felts covered by this specification are Type I, shingle undedayment and Type II, heavy-duty shingle undedayment. 

Asphalt (bitumen) also occurs in various oil sand (also called tar sand) deposits which occur widely scattered through the world (17) and the bitumen is available by means of various extraction technologies. A review of the properties and character of the bitumen (18) suggests that, when used as an asphaltic binder, the bitumen compares favorably with specification-grade petroleum asphalts and may have superior aging characteristics and produce more water-resistant paving mixtures than the typical petroleum asphalts. 

During the 1920s the following three national specifications for asphalt cements were pubHshed (/) Federal specifications, adopted in 1925 (2) the American Association of State Highway Transportation Officials (AASHTO) specifications, adopted in 1924, revised in 1926 and (2) ASTM specifications, adopted in 1922 to 1926, withdrawn in 1939, and re-issued in 1947. 

The Federal specifications stipulated that only those asphalts that had been demonstrated by service tests as satisfactory for the intended use would be accepted. The specifications also indicated the type and location of constmction and the relative amount of traffic for each of the grades. The AASHTO specifications indicated that the use of each grade depended on the type of road, climate, and traffic. The ASTM suggested the type of constmction for which each grade would be used. 

With minor exceptions the requirements for the physical and chemical properties of asphalt were essentially the same for the three national specifications and included penetration and ductiUty at 25 °C flash point % loss at 163 °C penetration of residue as a % of original solubiUty in carbon disulfide solubiUty in carbon tetrachloride specific gravity at 25°C and softening point. 

Specifications for paving asphalt cements usually include five grades differing in either viscosity or penetration level at 60 °C (Table 8) (ASTM D496). Susceptibihty of viscosity to temperature is usually controlled in asphalt cement by viscosity limits at a higher temperature such as 135 °C and a penetration or viscosity limit at a lower temperature such as 25 °C. 

Other additives. Amorphous polypropylene, waxes and asphalt can be added to decrease the cost of BR formulations. On the other hand, PIB can be blended with NR, styrene-butadiene rubber, EVA and low molecular weight polyethylene to impart specific properties. 

Mineral-dl, n. mineral oil specif., petroleum. -Slfimis, m. mineral-oil varnish. -SlrafBnat, n. refined mineral oil. -pech, n. mineral piteh, asphalt, -quelle, /. mineral spring or well, -reich,n. mineral kingdom, -rot,n. cinnabar. 

---