Investigation on Gaseous Product Distributions During Co-Pyrolysis of Platanus Wood and Different Rank Coals From Northwestern China in a Drop Tube Furnace

Abstract

Co-thermochemical conversion of municipal solid waste blends with coal has the advantage of diversifying energy resources and decreasing consumption of fossil fuels. As the initial and fundamental stage of co-thermochemical conversion, co-pyrolysis of municipal solid waste and coal has important influence on performance of the further co-combustion or co-gasification process. In this paper, gaseous product distributions during co-pyrolysis of platanus wood (wood waste from urban roadside trees platanus acerifolia) and two different rank coals (Shenmu bituminous and Pingzhuang lignite from northwestern China) were investigated through a semi-batch type drop tube furnace at different temperatures. The platanus wood/coal blends were fed into the furnace with five different mass ratios of 100/0, 70/30, 50/50, 30/70, and 0/100. The gaseous products (H2, CO, CO2, CH4 and light hydrocarbons) were continuously collected and then determined by gas chromatography. Experimental results indicated that the gaseous product distributions from pyrolysis of the platanus wood and coal blends were significantly affected by the temperature, the platanus wood/coal mass ratio and coal type. Compared the experimental results with the calculated values obtained from individual samples based on weighted average, some signs about positive or negative synergistic effect were observed on the formation of the major gas composition. The synergistic effect could probably be caused by the secondary reactions between volatiles and chars. In addition, the coal rank appeared to have different influence on the synergistic effect between platanus wood and coal during co-pyrolysis process.