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

滑铁卢生物过滤器是一家总部位于安大略省罗克伍德的公司，生产污水处理技术，特别是在非下水道开发中(www.water loo-biofilter.com)。核心技术是一种吸附滴滤器，用于将化粪池出水修复为“砂滤器质量”的出水。生物过滤器可以去除有机污染物和含氮污染物，但磷只能通过添加技术来去除，例如投加铝酸盐液体。这种方法价格昂贵，而且不断补充腐蚀性化学品、堵塞和冻结管道等，使其不切实际地用于小型设施和住宅。该公司开发了一种低成本的除磷系统，使用专有电化学过程(EC-PTM)产生的铁来隔离各种除磷过滤器基质中的磷酸盐。富含铁的EC-P废水(最好经过二级处理)将通过一种“磷回收介质”，例如玻璃硅酸盐纤维，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良剂。铁-磷酸盐矿物在基质中沉淀，磷在矿物中的有效性尚不清楚。圭尔夫大学的研究人员将与滑铁卢生物过滤器研究人员合作，研究土壤中饱和基质作为肥料土壤改良剂的再利用情况。

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.