Experimental Study On Preparation Of Liquid Oil By Co - Pyrolysis Of Waste Rubber / Plastic

The degradation-resistant wastes were very difficult to recyclingly treat, the pyrolysis of waste rubber and plastics powder for liquid fuel production has been investigated in this paper. The pyrolyzed experiments of two blending ratios fuels of rubber and plastics were carried out in TGA, to analysis the pyrolyzed characteristics,kinetic parameters and the influence of the blending ratios, and the verification tests were carried out in a fixed bed system. Then the waste rubber/plastic blends were pyrolyzed in a fixed bed system with few corn stalk additive to produce pyrolyzed oil, and the co-pyrolysis characteristics were analyzed. The influence of Fe2O3 and CaO as catalysts on the pyrolysis of waste rubber and plastics was to investigate in the next. In the end, the pyrolysis experiments were carried out in a continuous feeding rotary kiln pyrolyzer system, and the influence of residence time and temperature on the pyrolysis of waste rubber and plastics has been investigated.According to the TGA experiments, the pyrolysis process of rubber/plastics blends occurred to two stages, the first and the main stage achieved 85% of the whole pyrolysis,while the blending ratios did less influence on the pyrolysis temperature, but clear influence on the pyrolysis rate. The suitable blending pyrolysis temperature was 500℃.From the pyrolyzed oil collection in the fixed bed facility, the oil was of 38% yield, and HHV of 35MJ/kg. In the experiments of co-pyrolysis in a fixed bed system, the oil yield and liquid calorific value were increased by co-pyrolysis of rubber/plastics compared with the pyrolysis of the each material. When the mass proportion of rubber was 60%, the pyrolyzed oil yield rate reached the highest point. Adding 10% stalks into blends fuel contributed to the higher pyrolyzed oil production. When the ratio of rubber and plastics was 4:1 with 10% stalk additive, the oil yield achieved highest and the oil yield increased by 10.3%; the oil calorific value reached to 39.93MJ·kg-1. According to elemental analysis, a little sulfur content was remained in oil, H/C atomic mole ration in oil was increased after stalk additive. Through GC-MS analysis, the main components in the pyrolysed oil from the rubber and plastics blend were alicyclic hydrocarbon and aromatic hydrocarbon compound, while the oxygen-rich straw additive caused the higher content of alcohol, ester and ketone. Thus, the stalk additive is benefit for the pyrolyzed oil yield and the yield rate improvement for the co-pyrolysis of rubber/plastic blends. The catalysts accelerate the pyrolysis reaction to occur earlier and more quickly. With using the catalystof Fe2O3, the liquid yields increase to 49.84% and the gas to 22.51% respectively.Compared with Fe2O3, the CaO causes the yield of the pyrolysis liquid higher to 50.8%,while the gas less to 20.9%. In addition, the liquid products quality is improved obviously.The moisture content and kinematic viscosity are all reduced, and the calorific value is increased. The catalyst CaO is beneficial to desurferization and the sulfer concent in pyrolysis products reduced obviously. The pyrolysis in the rotary kiln device showed that the yields of gaseous and liquid product were increased with the longer residence time and the higher temperature. the extent of pyrolysis was maximum when the revolving speed was 1~2r/min and the temperature was 600℃.