ABSTRACT

Recycling phosphorus from waste activated sludge has attracted a lot of interest to tackle the problem of phosphorus stocks depletion and the increase in food demand. In this study, the use of fermentation processes was investigated to enhance phosphorus dissolution from waste activated sludge to improve its recycling. Two fermentation processes, bioacidification and dark fermentation, were used on two different sludges fermented with wheat starch syrup in continuous operating conditions. Hydrogen yield from the co-substrate fermentation with waste activated sludge reached 3.9 mmolH₂.gCOD_cosubstrate⁻¹ yield during dark fermentation process and was negligible during bioacidification. Dissolved phosphorus in the waste activated sludge increased by 68% during bioacidification and by 43% during dark fermentation. In both processes, phosphorus dissolution was accompanied by iron, calcium and magnesium dissolution. Results show that fermentation enhances phosphorus dissolution in waste activated sludge to improve its recovery along with hydrogen and organic acids.

摘要

从废活性污泥中回收磷已引起了人们的极大兴趣，以解决磷库存枯竭和食品需求增加的问题。在这项研究中，研究了使用发酵工艺来增强废活性污泥中磷的溶解，以改善其循环利用。在连续操作条件下，对两种用小麦淀粉糖浆发酵的不同污泥采用了两种发酵工艺，即生物酸化和暗发酵。与废活性污泥共底物发酵产生的氢气产量达到 3.9 mmolH ₂ .gCOD共_底物^-1在黑暗发酵过程中的产量和在生物酸化过程中可以忽略不计。废活性污泥中的溶解磷在生物酸化过程中增加了 68%，在暗发酵过程中增加了 43%。在这两个过程中，磷的溶解都伴随着铁、钙和镁的溶解。结果表明，发酵提高了废活性污泥中磷的溶解度，从而提高了其与氢气和有机酸的回收率。