Modification of bitumen using Shenhua coal direct liquefaction residues completed for the trial section of the Nandao Expressway

Thread Content

Paving of the test section of the Nandao Expressway using modified asphalt made from Shenhua coal direct liquefaction residues / Author/Source: Date: 12-14-2016 Clicks: 17 On December 9, the NDMA I-D modified asphalt derived from coal direct liquefaction residues, developed independently by the Low-Carbon Research Institute, was used to pave the test road for the surface layer of the asphalt mixture on the section K26+032-K26+930 of the Chongqing Nanchuan-Guizhou Daozhen Expressway (referred to as Nandao Expressway). This is the first time that modified asphalt made from coal direct liquefaction residues has been used in the hot and rainy regions of southern China as well as for highway paving, marking a new advancement in the research on such modified asphalt. The length of this test section is 900 meters, with two lanes in each direction plus an emergency lane, and the paving area exceeds 9,400 square meters. The test used NDMA I-D modified asphalt made from liquefied residue, which meets the I-D standard specified in the regulations of the Ministry of Transport (JTG F40-2004); this product was employed in tests on highways of higher grades. In early August, tests on sections of National Highway G110 in Ningxia (an area in northern China with low temperatures and little rainfall) utilized NDMA I-C modified asphalt made from liquefied residue, which complies with the I-C standard. The paving of the test section was carried out in collaboration with Chongqing Pengfang Pavement Engineering Technology Research Institute Co., Ltd. The results will further verify the actual road performance of asphalt modified with coal direct liquefaction residues in southern regions, expand the range of products made from such modified asphalt, accumulate experience in the industrial production of these products, and provide extensive application data to support the promotion of technologies related to asphalt modified with coal direct liquefaction residues. A total of 10 tons of liquefied residue modifier were used in the road section tests. This modifier was produced jointly by the Low-Carbon Research Institute and the Shanghai Research Institute of Shenhua Coal-to-Oil Chemical Co., Ltd. Using the modified asphalt production technology developed by the Low-Carbon Research Institute, 60 tons of NDMA I-D liquefied residue modified asphalt were manufactured at Chengdu Taihe Asphalt Development Company, which was then used to produce approximately 1,500 tons of asphalt mixture for the test road sections. Compared with the NDMA I-C liquefied residue modified asphalt product used on the test section in Ningxia, the NDMA I-D liquefied residue modified asphalt produced this time has a higher softening point and superior resistance to rutting at high temperatures, making it more suitable for use in hot and rainy regions in the south. After the test section is successfully paved, the project team will continue to monitor the relevant technical parameters of the pavement in order to evaluate its actual performance in use, and develop technical specifications for the production of modified asphalt using liquefied residue and for pavement construction. Given the differences in market demands and construction methods for different types of pavement layers in various regions, Low Carbon is actively working with relevant parties to establish industry standards, while also exploring commercial ways to put the results of coal liquefied asphalt research into practice.