Co-pyrolysis of two different types of biomass among apple tree branch (ATB), knotweed stem (KWS), seaweed (SW) and rice straw (RSt) was conducted to obtain co-pyrolysis char (co-char), and then the steam gasification of those co-chars was compared with the steam co-gasification of the physically mixed individual biochars to investigate the synergetic effect resulted from alkali and alkali earth metal (AAEM) in each biomass involved. It is found that the silica species in the RSt had negative effect on the activity of co-char due to the formation of alkali silicate compounds. However, combination of RSt with some non-woody biomass such as SW also showed promoting effect. In particular, the gasification of the co-char from the combination of various biomass with low or no silica content showed improved gasification efficiencies due to the synergetic effect AAEM species in the co-char from the different biomass. Therefore, the biomass selection should play a significant role in the co-pyrolysis of different biomass in the two-stage gasification system.

对苹果树分支（ATB），虎杖（KWS），海藻（SW）和稻草（RSt）之间的两种不同类型的生物质进行共热解，以获得共热解炭（co-char）。将这些共焦炭的蒸汽气化与物理混合的单个生物炭的蒸汽共气化进行了比较，以研究每种所涉及的生物质中碱金属和碱土金属（AAEM）产生的协同作用。发现由于碱金属硅酸盐化合物的形成，RSt中的二氧化硅物种对共焦活性具有负面影响。然而，RSt与一些非木质生物质（如SW）的组合也显示出促进作用。特别是，由于来自不同生物质的焦炭中的AAEM物种具有协同效应，因此由各种具有低含量或无二氧化硅含量的生物质组成的焦炭的气化显示出更高的气化效率。因此，在两阶段气化系统中，生物质的选择应在不同生物质的共热解中起重要作用。