STUDY ON THE NOX EMISSION FROM CO-FIRE OF PLASTIC POWDER AND BIOMASS IN CFB

摘要

A circulating fluidized bed(CFB) is build to study the NOx emission rules of biomass and waster plastic co-combustion. The experimental results show that NO is the major content of NOx emission, and the emitted concentration improves with the rising of temperature, while, decreases with the rising of excess air coefficient, but the rising gas velocity also aggravates the in-completely combustion. After mixed with biomass, the NOx emission concentration falls down with the rising of biomass and plastic mixture ratio, and lowers than the weighted average, which indicates some gas and volatile emitted during biomass pyrolysis have an inductive effect on NO formed by plastic combustion. Combined with the pyrolysis mechanism of biomass, a NOx formation model concerned with the CFB feature was brought out, and the inter-coupler of co-combustion on the NOx emission is analyzed. The simulation results have a good agree with the experiment data, and reveal that the CO and char actors the major roles in the NO reduce, while the homogeneous gas phase reaction has slight affection both on the produce and reduction of NOx.