Pitch prill

Asphalt, cut back Cut-backs Bitumen Pencil pitch Pitch prill Road asphalt Road asphalt or tar liquids Tars, liquid, 3.2, 3.3 Tars, liquid, including road asphalt and oils, bitumens and cut backs, 3 

Bituminous materials are dark brown or black, semi-solid or liquid, thermoplastic mixtures of hydrocarbons derived from natural or synthetic processes in which hydrocarbon mixtures have lost their volatile components leaving a denser residue. Natural bitumens come from exposed and weathered petroleum and rock deposits. Synthetic bitumens come from the residue remaining after the distillation of petroleum, coal tar, and other organic materials like wood and peat. The complexity of the high molecular weight hydrocarbon oils and resins bitumens contain make complete chemical characterization impossible. The terms bitumen, tar (8007-45-2), pitch (61789-60-4), and asphalt (8052-42-4) apply to any of these substances, although pitch and tar also describe the sticky resins that exude from various trees. 

Petroleum asphalt is used extensively as a binder in concrete road paving, hence road asphalt. Mixed with asphalt, coal tar pitch makes exceptional road surfaces that resist oils, are non-skid, adhere excellently to stone, and provide weathered hard surfaces. Cutback asphalt is asphalt dissolved in and made less viscous by a solvent (usually a petroleum distillate) allowing easier application in road repair and waterproofing. Road oil is very fluid asphalt used as a dust suppressant. 

Prills are small globules of material that are often of high purity either separated from inferior pieces or manufactured into granules, pellets, or cylinders by dropping the melted material from a height or other means. Pitch prills are spherical, granular, or cylindrical products pencil pitch) made from bitumens. 

Bitumens contain many chemicals of unknown toxicity and all will bum when heated to a sufficiently high temperature. Flammable solvents are widely added to bitumens to decrease their viscosity and improve handling. Bitumens may also be transported at sufficiently high temperatures to evolve these solvents and other flammable constituents in ignitable concentrations. 

---

Pitch prill, see also Solid Bulk Materials,... 

Pitch prill, prilled coal tar, and pencil pitch are combustible solids and dust irritants. 

Pencil pitch, see Bituminous Products, p.32 Petroleum Coke, see also Petroleum, p.l83 Pitch prill, see Bituminous Products, p.32 Prilled coal tar, see Coal, p.44... 

A schematic diagram of a prill tower is given in Fig. 7.7. Some details of an installation for fertilizer materials are listed in Table 1.2. Melt is provided to the prilling devices at the top of the tower from reactor/evaporator systems in the case of a fertilizer material such as ammonium nitrate or from a melt tank in the case of fusible materials such as petroleum wax and coal tar pitch. Melt droplets travel counter-current to cooling air and the solid prills are conveyed away from the bottom of the tower to appropriate downstream treatments such as cooling, clay treatment and storage. 

Rotary multitray dryer pulverized coal, pectin, penicillin, zinc sulfide, waste slude, pyrophoric zinc powder, zinc oxide pellets, calcium carbonate, boric acid, fragile cereal products, calcium chloride flakes, caffein, Inorganic fluorides, crystals melting near 100°F, prilled pitch, electronic grade phosphors, and solvent-wet organic solids... 

Pitch, a dark brown or black residue of toxic aromatic hydrocarbons and other compounds often used as road and roofing tar. Prilled coal tar is coal tar pitch manufactured into small globules or granules. 

---