不同Fe(Ⅲ)对活性污泥异化铁还原及除磷影响研究

Phosphorous removal using dissimilatory reduction of different Fe(Ⅲ) in activated sludge

以SBBR反应器活性污泥作为铁还原菌菌种来源,采用兼性厌氧/严格厌氧恒温培养试验,投加不同Fe(Ⅲ)考察各条件下的异化铁还原能力,同时比较对磷的去除效果.结果表明:2种条件下Fe(Ⅲ)还原能力具有较好的一致性,依次为:Fe(OH)3>氧化铁皮>青矿>红矿,其中严格厌氧条件下较好.同时,除磷效果与其呈正相关,富集培养至7d,Fe(OH)3及氧化铁皮体系出水磷浓度均达到2mg/L以下,之后继续降低,最终达到0.5mg/L以下.结合异化铁还原除磷机理,可以证明,不同Fe(Ⅲ)表面吸附作用对TP的去除贡献较小,其主要作用为铁还原菌驱动下的化学沉淀去除.

An enrichment culture of dissimilatory iron reduction by dosing different Fe（Ⅲ） sources at constant temperature under facultative/strictly anaerobic condition was investigated. The source of iron-reducing bacteria retrieved from the activated sludge of SBBR reactor. The ability of dissimilatory Fe（Ⅲ） reduction and the phosphorous removal efficiency under different conditions were compared. The results showed there was consistency in the Fe（Ⅲ） reduction ability of different conditions, followed by Fe（OH）3〉iron oxide scale〉green ore〉red ore, but strictly anaerobic showed better. While the phosphorus removal efficiency was positively related to produced Fe（Ⅱ） concentration. At the 7d of enrichment culture, the concentration of phosphate at Fe（OH）3 and iron oxide scale systems decreased below 2mg/L, and ultimately to 0.5mg/L. Bonding mechanism of phosphorous removal using dissimilatory Fe（Ⅲ） reduction, its main role of the precipitation removal by IRB rather than surface adsorption of Fe（Ⅲ） source was proved.