摘要
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生物质,而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。为此,以微囊藻生物质作为超临界水气化反应产氢原料,探究温度、介质密度及停留时间等反应条件对产氢特性的影响,优化微囊藻生物质超临界水气化反应工艺的能源转化效率和处理效果。试验结果表明,微囊藻生物质的产氢能力接近于微绿球藻、栅藻等常规能源化藻类生物质,且碱式添加剂的掺入能够极大程度上优化产氢效果。在500℃、NaOH掺入量为5. 0%条件下,H_2的产量可达17 mol/kg,且其含量(物质的量百分数)达到77. 39%。
The regular bloom of Microcystis results in a large amount of refractory waste Microcystis biomass with high water content every year. However,supercritical water gasification (SCWG) can realize reduction,harmless treatment and resource utilization of Microcystis biomass compared with dehydration processes with high energy consumption. The experiment focused on the process of supercritical water gasification reaction where Microcystis biomass was used as the hydrogen production raw material. The influences of reaction conditions such as temperature,medium density and residence time on the characteristics of hydrogen production were explored,and energy conversion efficiency and treatment effect of the process were optimized. The results indicated that the hydrogen production capacity of Microcystis was close to that of regular energy production microalgae,such as Nannochloropsis sp. and S. latissima,and the addition of alkaline additives could optimize hydrogen production to a great extent.When reaction temperature and dosage of NaOH were 500 ℃ and 5. 0%,the production of H_2 could reach 17 mol/kg with purity of 77. 39%.
引文
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