商洪国,吴楠,韩飞,张梦汝,周维芝.微藻对海水养殖循环水高效碳氮磷一体化去除的研究[J].环境科学学报,2021,41(9):3408-3417
微藻对海水养殖循环水高效碳氮磷一体化去除的研究
- Efficient simultaneous removal of carbon, nitrogen and phosphorus by micro-algae in seawater aquaculture recirculating water
- 基金项目：国家自然科学基金（No.U1906221）；国家重点研发计划（No.2018YFC0310704）；山东省科技创新重大专项（No.2018CXGC0307）
- 商洪国
- 山东大学, 土建与水利学院, 济南 250061
- 吴楠
- 山东大学, 土建与水利学院, 济南 250061
- 韩飞
- 山东大学, 土建与水利学院, 济南 250061
- 张梦汝
- 山东大学, 土建与水利学院, 济南 250061
- 周维芝
- 山东大学, 土建与水利学院, 济南 250061
- 摘要：海水养殖循环水高盐分和波动的低碳氮比造成水处理困难和亚硝酸盐累积，影响循环水处理利用，其排放造成受纳海域生态环境破坏.本研究采用混合营养型钝顶螺旋藻结合膜光合反应器（MPBR）考察碳氮比对海水养殖循环水碳、氮、磷一体化去除效率及藻生物质产量的影响.结果表明，在原水碳氮比为5时，钝顶螺旋藻可实现碳、氮、磷高效一体化去除，出水COD低于20 mg·L-1，满足《海水养殖水排放要求》（SC/T 9103—2007）一级标准，总氮和总磷浓度均满足二级标准.提高碳氮比有利于钝顶螺旋藻的生长、油脂累积和氮磷的去除，碳氮比为1~10时藻体内油脂含量由14.9%增到19.3%.钝顶螺旋藻膜光合反应器（MPBR）运行数据表明，聚偏二氟乙烯（PVDF）膜和无纺布生物膜均可高效稳定地截留微藻，稳定运行期出水COD、总氮和总磷浓度均满足《海水养殖水排放要求》（SC/T 9103—2007）二级标准，且均无亚硝酸盐累积.无纺布生物膜光合反应器COD去除效率（93.2%）和藻体的多糖含量（98.1 mg·g-1）显著高于PVDF膜反应器（85.2%和70.4 mg·g-1），膜通量也较低，膜污染较轻.本研究中钝顶螺旋藻结合无纺布动态生物MPBR不仅实现了海水养殖循环水高效的碳、氮、磷同步去除，无亚硝酸盐累积，并可稳定收获生物质资源，为海水养殖循环水高效、安全处理和资源化利用提供依据.
- Abstract：The discharge of seawater aquaculture recirculating water causes damage to the eco-environment of receiving waters. High salinity and varied carbon to nitrogen (C/N) ratios in seawater aquaculture recirculating water lead to difficulties for treatment and accumulation of nitrite, affecting the treatment and utilization of recirculating water. In the present study, mixotrophic Spirulina platensis and membrane photosynthetic bioreactor (MPBR) were utilized to investigate the impact of C/N ratio on the simultaneous removal efficiency of nutrients and the biomass production. Results showed that efficient simultaneous removals of carbon, nitrogen and phosphorus by Spirulina platensis were achieved under the C/N ratio of 5. The effluent COD concentration was lower than 20 mg·L-1, which satisfied the Class I water discharge standards for sea water mariculture (SC/T 9103—2007), and total nitrogen and total phosphorus of effluent met the Class II standards. The increase of C/N ratio was beneficial to the growth of Spirulina platensis, the accumulation of lipid and the removal of nitrogen and phosphorus. The lipid content of algae increased from 14.9% to 19.3% as C/N ratio increased from 1 to 10. results showed that both polyvinylidene fluoride (PVDF) membrane and the non-woven cloth could efficiently and stably retain Spirulina platensis dynamic biofilm. During the stable operation, COD, total nitrogen and total phosphorus of effluent were blow Class II water discharge standards for mariculture, without nitrite accumulation. With lower flux and less membrane pollution, non-woven cloth biofilm reactor showed significantly higher COD removal efficiency (93.2%) and content of polysaccharide (98.1 mg·g-1) than that of PVDF membrane reactor (85.2% and 70.4 mg·g-1, respectively). In this study, the Spirulina platensis non-woven cloth dynamic biofilm photosynthetic reactor could not only realize efficient simultaneous removals of carbon, nitrogen and phosphorus, but also stably harvest biological resources, providing the basis for efficient, safe treatment and resource utilization of seawater aquaculture circulating water.
