沼液培养的普通小球藻对CO_2的去除

Reduction of CO_2 by Chlorella vulgaris Cultured in Biogas Slurry

利用微藻固定CO2和处理污水已成为微藻应用的一个重要研究方向.利用营养丰富的沼气发酵废液培养小球藻,藻种经驯化后在不同浓度沼液中能良好生长.小球藻在高浓度的CO2中有较好的生长和较强的耐受能力,在1.5%CO2通气下生物量最高.在此基础上考察了沼液中小球藻对CO2的去除情况.结果表明,提高小球藻生长速率和CO2浓度可以增加小球藻对CO2的去除量,降低通气也可提高CO2去除率.在1.5%CO2浓度、通气量60 mL min-1条件下,CO2去除率可达30.61%;在10%CO2浓度、通气量100 mL min-1时最高去除量为279.7 mg L-1 h-1.采用六管串联通气培养小球藻去除粗沼气中的CO2,去除量为(205.80±13.20)mg L-1 h-1,去除率为60.32%±3.73%.在同样的通气量下,CO2的去除量与单管培养相近,去除率是单管培养的近6倍,因此小球藻对沼气中的CO2具有良好的去除效果.

The use of microalgae for CO2 fixation and wastewater treatment has been one of the most important research fields of microalgal utilization.In this study,Chlorella vulgaris was cultivated in nutritious effluent from methane zymolysis,and after domestication,C.vulgaris grew well in different concentrations of biogas slurry.C.vulgaris had excellent growth and tolerance to high concentrations of CO2,and the largest biomass productivity was obtained at the aeration of 1.5% CO2.Therefore,the CO2 reduction by C.vulgaris in biogas slurry was investigated.The results showed that increasing the growth rate of C.vulgaris and CO2 concentration could enhance the amount of CO2 reduction by C.vulgaris,and reducing the aeration also improved the removal efficiency of CO2.The CO2 removal efficiency reached 30.61% when the cultures were aerated with 1.5% CO2 at a rate of 60 mL min-1.Furthermore,When the cultures were aerated with 10% CO2 at a rate of 100 mL min-1,the maximum reduction amount of CO2 was 279.7 mg L-1 h-1.A six series-wound photobioreactor was used to reduce CO2 in crude biogas by C.vulgaris.The results revealed that the reduction amount of CO2 was similar in the single photobioreactor and in the six series-wound photobioreactor [（205.80 ± 13.20） mg L-1 h-1].But the reduction rate in the latter was 60.32% ± 3.73%,about six times higher than that in the former.The above results indicated that C.vulgaris had a remarkable removal effect on the CO2 in biogas.Fig 4,Tab 2,Ref 17