Monash Infrastructure Research Institute, Department of Civil Engineering, Monash University , Clayton, Victoria 3800, Australia.
Cooperative Research Centre for Water Sensitive Cities , Melbourne 3800, Australia.
Environ Sci Technol. 2017 Feb 21;51(4):2280-2287. doi: 10.1021/acs.est.6b04181. Epub 2017 Jan 31.
Phosphorus, a critical environmental pollutant, is effectively removed from stormwater by biofiltration systems, mainly via sedimentation and straining. However, the fate of dissolved inflow phosphorus concentrations in these systems is unknown. Given the growing interest in using biofiltration systems to treat other polluted waters, for example greywater, such an understanding is imperative to optimize designs for successful long-term performance. A mass balance method and a radiotracer, P (as HPO), were used to investigate the partitioning of phosphorus (concentrations of 2.5-3.5 mg/L, >80% was in dissolved inorganic form) between the various biofilter components at the laboratory scale. Planted columns maintained a phosphorus removal efficiency of >95% over the 15-week study period. Plant storage was found to be the dominant phosphorus sink (64% on average). Approximately 60% of the phosphorus retained in the filter media was recovered in the top 0-6 cm. The P tracer results indicate that adsorption is the immediate primary fate of dissolved phosphorus in the system (up to 57% of input P). Plant assimilation occurs at other times, potentially liberating sorption sites for processing of subsequent incoming phosphorus. Plants with high nutrient uptake capacities and the ability to efficiently extract soil phosphorus, for example Carex appressa, are, thus, recommended for use in greywater biofilters.
磷是一种关键的环境污染物，可通过生物过滤系统有效地从雨水径流中去除，主要通过沉淀和过滤。然而，这些系统中溶解流入磷浓度的归宿尚不清楚。鉴于人们越来越关注利用生物过滤系统来处理其他受污染的水，例如灰水，因此为了优化成功的长期性能设计，了解这一点至关重要。本研究采用质量平衡法和放射性示踪剂 P（作为 HPO），在实验室规模上研究了磷（浓度为 2.5-3.5mg/L，>80%呈溶解无机形式）在各个生物过滤组件之间的分配情况。种植柱在 15 周的研究期间保持了>95%的磷去除效率。植物储存是磷的主要储存库（平均占 64%）。截留于过滤介质中的磷有大约 60%可在顶部 0-6cm 中回收。P 示踪剂结果表明，吸附是系统中溶解磷的直接主要归宿（输入 P 的 57%）。在其他时间，植物会吸收磷，可能会释放出吸附位点以处理随后进入的磷。因此，具有高养分吸收能力和有效提取土壤磷能力的植物，例如垂穗薹草，被推荐用于灰水生物过滤系统。
