Experimental Research On Asphalt Modified With Nonmetals Separated From Waste Printed Circuit Boards

Along with the rapid development of road traffic, the highway asphalt pavement materials have become increasingly demanding, and more modified asphalt will be developed to solve the performance problem of modified asphalt mixture performance. At the same time, the growing waste printed circuit board (PCBs) cause serious environmental pollution, making the recycling of PCBs need to find more ways.Nonmetal components of PCBs are recycled and added to asphalt to make a new asphalt modified, named nonmetals modified asphalt, the road performance of which will be tested and evaluated in this paper. Hope the study of this issue making waste to treasure. While developing a new modified bitumen materials, providing an environmental and economical solution for waste PCBs problems.In this paper, based on the reference to domestic and foreign research, the basic nature and the chemical mechanism of nonmetal components in waste PCBs, the existing recycling technology of waste PCBs and the asphalt modified technology will be researched by combining theoretical and experimental method. From the above basis, testing on modified asphalt by using nonmetal powder from waste PCBs. The experiments include the processing technology of modified asphalt, the modified asphalt basic performance test and rheological properties test, modified asphalt mixture performance test.The research of modified asphalt processing technology carries on orthogonal experimental design in nonmetal powder content, fineness, reaction time and reaction temperature. The results show that nonmetal powder content and fineness is significant on the impact of modified asphalt. With the content of PCBs nonmetal powder increasing and fineness decreasing, the performance of modified asphalt is gradually improved.By the the basic performance test and rheological properties test of modified asphalt, the addition of nonmetal powder improves softening point, viscosity and rutting factor of asphalt, and decreases penetration, ductility, which indicate that nonmetal constituents enhance temperature performance of asphalt and reduce the temperature sensitivity of asphalt. However, nonmetal components modified asphalt has less significantly improvement at low temperature performance and anti-aging performance.Performance test of nonmetals modified asphalt mixture also show that the modified asphalt has better high temperature stability compared to general asphalt. Taking into account the impact on the performance of modified asphalt and the economic and technology of modified asphalt preparation, when content of waste PCBs nonmetal powder is 8%, modified asphalt would reach the best performance. In addition, to further raise the application of waste PCBs nonmetal powder, a feasibility study of using nonmetal powder as slag powder filler is carried on, and obtains satisfactory results, which expand the using range of waste PCBs nonmetal powders.