生物/化学氧化对铅山煤硫分去除及燃烧的影响

Influence of Biological/Chemical Oxidization on Sulfur Removal and Combustion Properties of Yanshan Coal

介绍了一种简单、温和、成本低的煤炭燃前脱硫新工艺——生物/化学氧化法.将铅山煤生物处理(混合氧化亚铁硫杆菌生物沥滤)12d后,处理煤样再置于曝气反应器中深度氧化4h(90℃,0.05mol/LNaOH溶液).处理前后的煤样使用氧弹法、亚硝酸钠爆燃法、X-射线衍射、热重和扫描电镜进行分析.结果表明:化学氧化后,原煤(VC)和生物预处理煤(BTC)总硫去除率分别为47%和63%;其中BTC的硫化铁硫和有机硫去除率分别为94%和24%,比VC的两种硫分去除率分别提高了27%和118%.与VC相比,生物/化学处理煤(B/CTC)燃烧值提高了11%,起燃点降低了15℃.X-射线衍射、热重和扫描电镜的分析结果表明煤经生物处理后结构松动.因此,硫分和矿质成分更易于被化学处理,这使得煤炭既降低了硫分又提高了燃烧性能.

A simple,mild and cost effective coal desulfurization process prior to combustion,i.e.biological/chemical oxidization,was described in this work.After leached for 12dby the mixed culture of Thiobacillus ferrooxidans,Yanshan coal was put into an aeration reactor filled with 0.05mol/L NaOH solution to treat for 4hat 90℃,with air as oxidant.The coal samples before and after the treatment were analyzed by the oxygen bomb test,sodium nitrite explosion method,XRD,TG and SEM.The results show that after the chemical oxidization 47%and 63%of the total sulfur removal were obtained for the virgin coal（VC）and the biologically pre-treated coal（BTC）,respectively.The pyritic sulfur and the organic sulfur removal rates of the BTC were observed to be 94%and 24%,which were higher than that of the VC by 27%and 118%,respectively.Compared with the VC,the biologically/chemically treated coal（B/CTC）had better combustion properties,with calorific value increased by 11%and ignition temperature reduced by 15℃,respectively.The results of XRD,TG and SEM show the structure of the coal sample was loose after the biotreatment.Thus,the sulfur and mineral presented in the coal were easily to be treated by chemical methods,which resulted in sulfur reduction and combustion properties increase for the B/CTC.