酱油废水混凝处理的特征及机理研究

将酱油废水混凝沉淀过程中产生的物化污泥 ,回流至混凝反应的前段 ,加以重复利用 .试验表明 ,回流污泥与PAC、石灰混合后适用于高浓度的老抽酱油废水的混凝预处理 .污泥回用量为 5 0mL·L-1,PAC与石灰的投药量为 4 8mL·L-1,3 6g·L-1,比没有污泥回流时的 8 0mL·L-1,6 0g·L-1,减少了 4 0 % ,预处理过程中的沉淀污泥总产量下降 2 8 4 % .在此条件下 ,COD和色度平均去除率分别为 4 4 2 %和 93 2 % .结合透射电镜图片的机理分析表明 :石灰中的CaO可与废水中的糖类等物质反应生成沉淀 ,在回流污泥吸附卷扫与PAC电性中和的共同作用下 ,色度和COD得到明显去除 .

Study on characteristics and mechanisms of sauce wastewater's flocculation treatment

The physical-chemical sludge from flocculation process in treatment unit for sauce wastewater was recycled to the forepart of flocculation unit. Experiments showed that mixture of the recycled sludge, and additions of PAC and lime was favorable for the treatment of high concentration of sauce wastewater. The optimal recycle concentration of sludge was 50mL·L^-1. The average dosages of PAC and lime were 4.8 mL·L^-1} and 3.6g·L^-1, both less than the dosages where no sludge was reused. And the sludge production reduced by 28.4%. At this condition, the average remove rates of COD and color were 44.2% and 93.2% respectively, close to the level where no sludge was reused. Together with the results of transmission electron microscope observation on sludge, mechanisms analysis showed CaO could react with certain carbohydrates to form precipitation. COD and color were removed dramatically by the adsorption and sweep of the reused sludge and through charge neutralization by PAC.