生物絮凝反应器处理水产养殖废水的中试研究

运用序批式生物絮凝反应器,研究不同混合液悬浮固体浓度(MLSS,1 500 mg/L、3 000 mg/L和5 000mg/L)下反应器对循环水养殖系统吉富罗非鱼(GIFT Oreochromis niloticus)养殖废水的处理效果。结果表明:反应器内氨氮(TAN)、亚硝氮(NO-2-N)和硝氮(NO-3-N)出水浓度分别为(0.29~0.39)mg/L、(0.005~0.006)mg/L、(7.11~7.60)mg/L,平均去除率分别为82.20%~86.20%、98.40%±0.89%、38.40%~40.00%(P0.05),体积去除负荷为(2.51~2.64)g/(m3·d)、0.56 g/(m3·d)、(8.52~9.78)g/(m3·d);溶解性无机氮(DIN)的去除率为43.20%~44.60%,体积去除负荷为(10.25~11.61)g/(m3·d)。三组絮体蛋白质含量差异不显著,分别为30.00%±1.32%、29.87%±0.67%、31.00%±0.75%;粗脂肪含量分别为9.51%±0.94%、4.37%±0.42%、3.65%±0.22%,MLSS 1500 mg/L组显著高于其他两组(P0.05)。微生物群落结构分析表明反应器中生物絮体主要为变形菌门(44.66%、44.51%、44.29%),其次是拟杆菌门(13.89%、13.98%、14.07%);优势菌属包括Alishewanella、Blastocatella、Amaricoccus、Rhodobacteraceae_unclassified、Terrimonas、Devosia等。实验表明中试生物絮凝反应器具有较好的脱氮效果,有助于实现养殖废水的资源化应用。

Pilot-scale study on sequencing batch reactor to treat aquaculture wastewater by biofloc technology

Three pilot sequencing batch reactors (SBRs) were employed to treat aquaculture wastewater from a recirculating aquaculture system (RAS) stocking GIFT Oreochromis niloticus using biofloc technology (BFT), under three designed MLSS (1 500 mg/L, 3 000 mg/L, 5 000 mg/L). The results showed that, the effluent concentrations of ammonia (TAN), nitrate (NO₂^--N) and nitrate (NO₃^--N) in SBRs were (0.29-0.39) mg/L, (0.005-0.006) mg/L, and (7.11-7.60) mg/L, respectively; these average removal rates were 82.20%-86.20%, 98.40%, and 38.40%-40.00%, respectively (P>0.05); the volume removal loads were (2.51-2.64) g/(m³·d), (0.56±0.08) g/(m³·d), and (8.52-9.78) g/(m³·d); meanwhile, the removal rates and volume removal loads of solubility inorganic nitrogen (DIN) were 43.20%-44.60%, (10.25-11.61) g/(m³·d). However, the protein contents of flocs from SBRs showed no significant differences among the three groups, as 30.00%±1.32%, 29.87%±0.67%, and 31.00%±0.75%, respectively. The crude lipid contents were detected at 9.51%±0.94%, 4.37%±0.42%, and 3.65%±0.22%, and the crude ash content in 1 500 mg/L group is significantly higher than those in the other two groups (P<0.05). Besides, analysis of high-throughput sequencing revealed that Proteobacteria accounted for the most phyla of bioflocs in SBRs (44.66%, 44.51%, 44.29%), followed by Bacteroidetes (13.89%, 13.98%, 14.07%); at the genus levels, Alishewanella, Blastocatella, Amaricoccus, Rhodobacteraceae_unclassified, Terrimonas and Devosia were identified to be the dominant genera. All the results suggest that the pilot SBRs have good effects on nitrogen removal, and will contribute to realizing the resource utilization of aquaculture wastewater.