气流床气化细渣中碳-灰的结合形态及其解离特性

Combined morphology and dissociation characteristics of carbon-ash in fine slag of entrained flow gasification

煤气化细渣中碳-灰分离是实现其高效利用的关键,探明碳-灰的结合形态并将二者有效解离是分离的前提.本文将宁东西门子GSP粉煤气化工艺产生的细渣分为3个粒级,分别为<0.074 mm,0.074~0.250 mm和>0.250 mm,采用拉曼(Raman)光谱、X射线荧光光谱分析(XRF)和扫描电镜考察碳-灰的结合形态,并研究超声处理和磨矿处理下的解离特性.结果表明:<0.074 mm粒级灰分为81.37%,细灰以无定形态融合于致密碳基体上;0.074~0.250 mm粒级碳含量高达49.09%,球形灰填充于多孔碳的孔隙中;>0.250 mm粒级灰分高达87.76%,少量碎屑碳附着在球形灰粒上.超声处理可将多孔碳孔隙的灰粒剥离,有利于从高碳组分(0.074~0.250 mm)中回收多孔碳;磨矿处理可实现高灰组分(<0.074 mm和>0.250 mm)中碳-灰的充分解离,有助于碳-灰的分离利用.以上结果可为GSP细渣的处理提供依据.

The separation of carbon-ash in coal gasification fine slag is the key to realize its efficient utilization,and it is a prerequisite to explore the combined form of carbon-ash and dissociate the two effectively.In this paper,the fine slag produced by the Siemens GSP pulverized coal gasification process in Ningdong was classified into three particle classes,which were<0.074mm,0.074~0.250mm and>0.250mm,and Raman spectroscopy,XRF and SEM were used to investigate the carbon-ash binding morphology and to study the dissociation characteristics under ultrasonic treatment and grinding treatment.The results show that the ash content of<0.074mm grain level is 81.37%,and the fine ash is fused to the dense carbon matrix in an amorphous form;the carbon content of 0.074~0.250mm grain level is up to 49.09%,and the spherical ash is filled in the pores of porous carbon;the ash content of>0.250mm grain level is up to 87.76%,and a small amount of debris carbon is attached to the spherical ash particles.Ultrasonic treatment can strip the ash particles from the porous carbon pores,which is conducive to the recovery of porous carbon from the high carbon fraction(0.074~0.250mm),grinding treatment can achieve the full dissociation of carbon-ash from the high ash fraction(<0.074mm and>0.250mm),which helps the separation and utilization of carbon-ash.The above results can provide a basis for the treatment of GSP fine slag.