油页岩干馏气与半焦中硫的分布特性

Sulfur release and distribution in retorting gas and solid waste

针对桦甸油页岩和汪清油页岩样品,通过程序升温控制干馏法,考察水蒸气质量分数以及操作气速对H2S气体的释放过程的影响,并对干馏后的半焦进行各形态硫分析。结果表明:混合气氛中蒸汽对气态硫的析出具有显著的促进作用,当蒸汽质量分数为22%时,桦甸和汪清油页岩的H2S释放总量分别提高了75.63%和37.16%。同时,气体流速促进硫的析出也较为显著。蒸汽气氛促使整个反应出现2个释放高峰,并且随着蒸汽量的增加,第2个释放高峰更为明显;操作气速的增加对传质具有积极作用;相对而言,桦甸样品的分解更为剧烈,有机硫为最主要的分解部分;在蒸汽与氮气的混合气氛下硫酸盐硫几乎不分解;桦甸样品中的硫更多进入到了干馏气中,而汪清油页岩的干馏气与半焦中的硫含量非常接近,2种样品的油页岩和冷凝水中的硫含量均小于其他2项。

The H2 S release was measured during oil shale retorting at different mass fractions of water vapour and gas velocities by means of programmed temperature rise,followed by the analysis on the forms of sulfur distributed in semi-cokes taken out at various temperatures during oil shale distillation.Samples were selected from the oil shale deposits of Wangqing and Huadian.The results show that H2 S release is tremendously affected by occupation of water vapour in mixed gas,especially 22%steam （mass fraction）in the mixed gas helps Huadian and Wangqing oil shale increase their yielding of hydrogen sulfide by 75.63%and 37.16%individually.Meanwhile,gas velocity also promotes gaseous sulfur release obviously.Water vapour helps samples release gaseous sulfur with occurring two peaks during pyrolysis process,especially the second peak appears more obvious with the increasing of vapour content.Increasing gas velocity is favorable to mass transfer.Huadian oil shale decomposes more intensely compared with Wangqing sample during the distillation.The decomposition of organic sulfur is the main part of reaction while the sulfate sulfur is hardly decomposed in the mixed gas.Most part of sulfur content transfers to retorting gas for Huadian oil shale,while the sulfur content of retorting gas is nearly equal to that in semi-coke.The sulfur contents distributed in shale oil and condensate water are less than that of the other two retorting products.