摘要
采用新型序批式气升内循环生物膜反应器(BSBAR)对混合营养型小球藻进行挂膜培养以去除黑臭水体中的氮、磷污染物。经过7 d的培养,BSBAR中附着生物量比悬浮序批式气升内循环藻类反应器(SBAR)高37. 5%,悬浮生物量一直维持在12 mg/L以下,降低了藻流失量,有利于收获藻类。BSBAR的藻类产率达到0. 096 g/(L·d),是SBAR的1. 30倍。并且BSBAR中的附着微生物具有更高的胞外多糖含量和脱氢酶活性,反应器的稳定性和污染物去除速率明显增强。当进水NH_4~+-N和PO_4~(3-)-P浓度分别为17和8 mg/L、HRT为4 d时,BSBAR出水NH_4~+-N和PO_4~(3-)-P浓度可分别降至1. 64和0. 19 mg/L,去除率分别为90. 4%和97. 6%,达到《地表水环境质量标准》(GB 3838—2002)Ⅴ类水标准。因此,利用序批式气升内循环混合营养型藻类生物膜反应器处理黑臭水体,不仅可以提高藻类产率,净化水质,还能解决藻类收获难题。
A novel biofilm sequencing batch air-lift reactor (BSBAR) was used for attached mixotrophic microalgae culture to remove nitrogen and phosphorus from black odorous water. After 7 days of culture,the concentration of attached biomass in BSBAR was 37. 5% higher than that in suspended sequencing batch air-lift reactor (SBAR). The suspended biomass concentration was maintained under12 mg/L,which could reduce the loss of algae and was beneficial to algal harvest. The algal yields of BSBAR reached 0. 096 g/(L·d),which was 1. 30 times that in SBAR. And the attached biomass in BSBAR had a higher concentration of extracellular polysaccharide and dehydrogenase activity, the stability of the reactor and the removal rates of pollutants were obviously enhanced. When the influent NH_4~+-N and PO_4~(3-)-P concentrations were 17 mg/L and 8 mg/L respectively,and HRT was 4 d,the NH_4~+-N and PO_4~(3-)-P concentrations of effluent were reduced to 1. 64 mg/L and 0. 19 mg/L respectively by BSBAR, the removal rates reached 90. 4% and 97. 6%, respectively. It was in accordance with class Ⅴ criteria in Environmental Quality Standard for Surface Water (GB 3838-2002). Thus,the treatment of black odorous water by mixotrophic algal biofilm in SBAR can not only improve algal yield,purify water quality,but also solve the problem of algal harvest.
引文
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