USE OF COAL LIQUEFACTION HEAVY RESIDUE AS AN ADDITIVE FOR PAVING ASPHALT

摘要

The heavy load and flux of modern transportation demand high performance of road. The limited lifetime of the road surface mainly is due to the aging of the paving asphalt. Paving asphalt on road experiences a wide range of static and dynamic stress at varying temperatures under different environmental conditions [1]. Asphalt from heavy petroleum resid itself is hard to satisfy the requirement in quality. To improve the performance, using asphalt modifier is one of the key techniques [2]. Asphalt modifier, in general, may be separated into two major groups: polymer type and others. The former, such as SBS, reclaimed rubber and pulverized waste tire, is well known and widely used due to its modification ability and reliable resource. It, however, involves certain problems related to the chemical structure difference between the polymer and petroleum asphalt, although this difference may be necessary for its modification ability. The later includes sulfur, carbon black, fiber and naturally occurring asphalt. Trinidad Lake Asphalt (TLA) is special nature asphalt. It has excellent modification ability to improve durability of an asphalt surface, adhesion of asphalt to aggregate, deformation resistant at great load, water resistance and freeze resistance. It bas been used in pavement applications worldwide, such as in USA, UK, Germany, Japan and China [3]. In China TLA is used only in limited places due to its high price ($500-$800/t) and large amounts of addition (25-50%), which result in high capital cost compared to use of other additives.