烘焙稻壳与煤混烧中PM_(10)生成特性研究

Study of Formation Characteristics of PM_(10) During Co-combustion of Torrefied Rice Husk and Coal

本文通过对一种亚烟煤、烘焙稻壳及其不同比例的混合物在沉降炉上的燃烧实验,研究了其颗粒物的生成特性。研究发现,烘焙稻壳与煤混烧的交互作用对PM_1与PM_(1-10)的排放具有控制作用,且烘焙稻壳掺混比例越大,控制效果越明显。混烧促进了对碱金属的固化,因而减少了碱金属气化凝结生成的PM_1;多孔的烘焙稻壳灰对煤灰细颗粒具有包裹捕集作用,在大掺混比例下,两者会发生明显的交互反应,导致PM_(1-10)向PM_(10+)迁移,从而减少了混烧过程中PM_(1-10)的生成。

This study researched the formation characteristics of particulates during combustion of a kind of subbituminous coal, torrefied rice husk and their blends with different ratios in drop tube furnace. The results indicated the interactions in co-combustion of torrefied rice husk with coal inhibited the emission of both PMi and PM1-10, the control effect improved along with increasing the ratio of torrefied rice husk. Co-combustion promoted the retention of alkali in bulk ash, it resulted in reduction of PMi formed from gasification-condensation of alkali. The porous ash from torrefied rice husk could wrap the ash particles from coal, and significant reactions occurred at high blend ratio of torrefied rice husk. As a consequence, PM1-10 transformed to PM10＋ and the emission of PM1-10 diminished.