利用嗜酸性硫杆菌的生物产酸作用处理洗毛废水

利用洗毛废水在低pH条件下,有机物絮凝沉降的特点,通过嗜酸性硫杆菌(Acidophilic thiobacillus)的产酸作用降低体系pH,破坏废水固有的稳定性,改变有机物的亲水性能,实现固液分离,达到去除COD的目的.试验结果表明,生物产酸作用能有效地去除废水COD,改善其脱水性能.当体系pH降至3.00, COD去除率达到最大值91.4%,处理后的废水有很好的机械脱水和沉降性能,比阻从大于9.81×10¹³　m·kg^-1降至5.60×10¹¹ m·kg^-1.而对照处理在整个培养期内,未发生明显的改变,仅有20%的COD被去除.本研究为油脂含量高、难被生物利用的有机废水提供了一条新的处理方法.

Acidification Treatment of Woolscouring Effluent by Using Acidophilic thiobacillus

Suspended solids dispersed in woolscouring effluent (WSE) could be flocculated and precipitated in low pH. The aim of this study is to decrease pH in WSE, result in liquid-solid separation and remove COD of WSE through bio-acidification of Acidophilic thiobacillus. Acidophilic thiobacillus TS6 and sulfur powder as energy substance were inoculated and added into WSE for incubation in shaker at 180 r/min and 30 degrees C for 12 d. The results showed that suspended solids in WSE would flocculate and precipitate spontaneously and rapidly when pH in WSE drops to 3.00 due to bio-acidification. As a result, 91.4% of COD could be removed through consequent liquid-solid separation. Throughout the experiment, the control without inoculated with Acidophilic thiobacillus only led to 20% of COD removed. Furthermore, dewaterability of the sediment or dreg in bio-acidification treatment was enhanced markedly, as indicated by the decline of its specific resistance from more than 9.81 x 10(13) m x kg(-1) to 5.60 x 10(11) m x kg(-1). It seemed that bio-acidification approach might be an attractive treatment method for the organic wastewater of high wax content or high suspended solids content.