中文摘要：

烘焙和酸洗都是可提升生物质品质的预处理方法。烘焙可以脱除生物质中的氧,酸洗则可有效脱除碱金属及碱土金属,而氧和AAEMs对热解油的品质和产率均具有影响。该文研究了酸洗-烘焙两级耦合预处理对玉米秸秆热解特性的影响。试验用酸液取自热解联产联供示范项目热解油的水相部分,烘焙温度选取230、260、290℃。研究发现,酸洗预处理能够有效脱除AAEMs,对K、Na、Mg脱除率分别达到97.53%、81.38%、84.86%。两级预处理能明显降低O/C;酸洗-290℃烘焙半焦相比玉米秸秆原样,O/C降低了25.32%。两级预处理能明显削弱烘焙对热解油产率的不利影响,酸洗-290℃烘焙半焦相比290℃烘焙半焦,其热解油产率提高127.66%;两级预处理显著提高了热解油中糖类的含量,同时降低了酚类和酸类的含量;对酸洗-290℃烘焙半焦,其热解油中糖类含量高达45.89%,酚类和酸类则低至9.76%和6.31%。其他化学组成如酮类和呋喃类的含量存在一定程度的下降,醛类含量则有小幅度的提升。该文提出的利用热解联产联供示范项目热解油的水相部分对秸秆进行酸洗,并结合烘焙的两级预处理方法可为对生物质热解提供参考。

英文摘要：

Torrefaction and acid-washing are both the pretreatment methods to improve the quality of biomass. Torrefaction can remove oxygen in the biomass, and acid-washing can effectively remove alkali metals and alkaline earth metals （AAEMs）. Both oxygen and alkali metals and alkaline earth metals have effect on the quality and yield of pyrolysis oil. However, after torrefaction, there are still a lot of alkali metals and alkaline earth metals remaining in the biomass. Therefore, it is necessary to take appropriate pretreatment methods to remove alkali metals and alkaline earth metals. But acid-washing can not remove oxygen from the biomass. Therefore, for improving the quality of biomass, torrefaction and acid-washing have some limitations. At present, there are many researches on torrefaction and acid-washing, but the the coupling effect of the torrefaction and acid-washing on pyrolysis characteristics is rarely reported. In this paper, a method of two-stage pretreatment by acid-washing and torrefaction was proposed and the coupling effect of the torrefaction and acid-washing on pyrolysis characteristics of corn stalk was studied. The acid liquor was taken from the aqueous portion of the pyrolysis oil from a demonstration project. If the aqueous portion can be used for washing biomass, it is beneficial to increase the benefit of the system and realize the internal circulation of industrial materials. The torrefaction temperature is 230, 260 and 290 ℃. It is found that the AAEMs can be effectively removed by acid-washing, and the removal rates of K, Na, and Mg are 97.53%, 81.38% and 84.86%, respectively. Two-stage pretreatment can significantly reduce O/C ratio; compared to the original corn stalk, the O/C of semi-coke with washing-torrefaction under 290℃ reduces by 25.32%. Two-stage pretreatment can obviously reduce the unfavorable effects of torrefaction on oil yield; compared to 290℃ torrefaction semi-coke, the oil yield of semi-coke with washing -290℃ torrefaction increases by 127.66%. Compared to origin