Recovery & re-use of sewage phosphate as a fertilizing soil amendment

Waterloo Biofilter是一家位于安大略省Rockwood的公司，专门生产污水处理技术，特别是在非下水道开发（www.waterloo-biofilter.com）。核心技术是将化粪池污水修复为砂滤水质的吸附性滴流过滤器。生物过滤器可以去除有机和含氮污染物，但磷只能通过附加技术去除，例如添加液体铝酸盐。这种方法很昂贵，并且不断地重新供应腐蚀性化学品，堵塞和冻结管道等，使得它不适合在小型设施和住宅中使用。该公司开发了一种低成本的除磷系统，利用专有的电化学过程（EC-PTM）产生的铁，将磷酸盐隔离在各种除磷过滤基质中。富含铁的EC-P废水（最好是预处理到二级质量）将通过“磷回收介质”，如玻璃硅酸盐纤维，这是目前磷回收介质的重点，因为它已经被用作质地土壤改色剂。磷酸铁矿物在基质中沉淀，而在矿物中封存的磷的有效性是未知的。圭尔夫大学的研究人员将与滑铁卢生物过滤器公司的研究人员合作，研究土壤中饱和基质作为土壤改良剂的再利用。

Waterloo Biofilter is a company based in Rockwood, Ontario that manufactures technologies for sewage treatment, specifically in off-sewer developments (www.waterloo-biofilter.com). The core technology is an absorbent trickle filter for remediation of septic tank effluent to 'sand filter quality' effluent. The Biofilter removes organic and nitrogenous contaminants, but phosphorus is only removed with add-on technologies, such as dosing of liquid aluminate. This approach is expensive, and constant re-supply of caustic chemical, plugging and freezing of pipes, etc., makes it impractical for use at small facilities and houses. The Company has developed a low-cost phosphorus removal system using Fe generated by a proprietary electrochemical process (EC-PTM), to sequester phosphate in a variety of P-removal filter matrices. The iron-rich EC-P effluent (preferably pretreated to secondary quality) will pass through a 'P-recovery medium' such as vitreous silicate fiber, the present focus for P-recovery medium, as it is already used as a textural soil amendment. Iron-phosphate minerals precipitate in the matrix, and the availability of the P sequestered in the minerals is unknown. Researchers at the University of Guelph will collaborate with Waterloo Biofilter research staff to investigate the re-use of the saturated matrix in soil as a fertilizing soil amendment.