微囊藻生物质性质对超临界水气化产氢的影响

Influences of Biomass Characteristics on Gasification of Cyanobacterial Biomass in Supercritical Water

微囊藻水华的常态化暴发致使每年产生大量难处理的高含水率废弃微囊藻生物质,超临界水气化技术可越过高能耗的脱水工艺实现其减量化、无害化处理及资源化利用。该文聚焦微囊藻生物质作为超临界水气化反应原料、在堆积及自然腐解条件下的初始含水率及腐解程度变化,明确生物质原料初始含水率及腐解程度等条件与超临界水气化产物的质量分布规律、产气产氢特性、以及能耗分析的作用关系。70%～96.15%范围内的含水率变化对微囊藻生物质SCWG产氢存在一定影响,在其脱水能耗允许程度内降低含水率能够有效改善处理效率及能源转化效率;微囊藻生物质15 d腐解程度时TOC约降低15%,而该阶段的产氢效率能够稳定维持在3.0 mol/kg左右。研究成果将为今后微囊藻生物质超临界水气化处理的高能效产业化应用提供必要的理论支撑依据。

Cyanobacterial bloom broken out in freshwater lakes always bring about huge amount of waste of intractable algae biomass rich in water content.This paper introduces a technology of supercritical water gasification(SCWG)with which mass reduction by dewatering and resource utilization of the algae biomass can be realized.The technology focuses on the use of cyanobacterial algae mass as materials of SCWG,and the change of moisture content and natural decomposition of raw cyanobacterial biomass.Laboratory experiment was conducted exploring the effects of raw feedstock characteristics on the mass distribution of reaction products,the characteristics of gasification and the analysis of energy consumption.The results indicated that H2 production of cyanobacterial SCWG was affected by changing moisture content of raw biomass in the range of 70%~96.15%,and lowering the moisture content of algae biomass by dewatering practices within the allowed limit of energy consumption would result in higher efficiency of treatment and energy conversion.Furthermore,TOC was reduced by 15%as the fresh cyanobaceria underwent 15 d natural decaying and decomposition,but the efficiency of H2 yield could hold steady at about 3.0 mol/kg.In conclusion,the optimization of efficiency of energy conversion in the process of SCWG would boost the application of SCWG of cyanobacterial biomass and furthermore,the industrialization in the future.