Study On Production Process Technology And Quality Control Of Heavy Traffic Paving Asphalt

Lanzhou petrochemical company began its exploration of heavy traffic paving asphalt from 1994. The dumbbell-shape concoction process was adopted which was presented by Corbett in 1979. In this process, the deoiled asphalt with moderate penetration number, which is produced by solvent extraction, was concocted with an aromatic-rich containing fraction in certain proportion by tank concoction method. With concoction of residuum extracted oil with propane deoiled asphalt, HTPA were produced in agreement with national standard of China, GB/T15180. However, due to the limitation of residuum extracted oil output and sometimes the whole-plant production scheme of lubricating oil, the increase of HTPA production is restricted to some extent. Furthermore, because of the high content of wax in extracted oil, the 15℃ductility of HTPA after TFOT test is far lower than that of international standard (ESSO), whose specification is higher than 100cm. Therefore, with current two-component concoction process, the yield and quality of HTPA would inevitably be restricted.With the initial of 3M ton/a heavy oil catalytic cracking unit in Lanzhou petrochemical company, the discharging of catalytic slurry will increase. If the discharging is 5%-6%, the output of slurry would reach to 165,000 tons annually. Due to its low value, the slurry is generally used as fuel oil component that also worth less. Therefore the income will be insignificant to the company. However such aromatics-rich alkane-low slurry is important in increasing output of asphalt if it is used as concoction component.By making an investigation on quality situation of products worldwide and domestic production of heavy traffic paving asphalt, problems of current production in Lanzhou petrochemical company are found out, and corresponding solutions are presented. The main reason of fluctuate in product quality, especially in high wax content and low ductility after TFOT test, is that the properties of asphalt concocting components are unstable. In order to solve the problem and broaden the source of raw materials, the components of deoiled asphalt and residuum extracted oil were...