硫酸盐还原过程中碱度的平衡与调节

为探讨硫酸盐还原过程中碱度的变化规律,采用产酸脱硫反应器通过连续流运行处理硫酸盐废水。在硫酸盐去除率达到最大并稳定时,探讨硫酸盐还原反应体系碱度的组成和计算方法,挥发酸(VFA)与pH值对碱度平衡的影响,体系中各种碱度形式的相互转化等。试验结果表明,硫酸盐还原过程碱度增加,各种形式的碱度之间会发生相互转化;碱度组成与体系pH值直接相关,pH=6.0～6.2时,产酸脱硫反应器中硫酸盐去除率和体系中的碱度值最大;产酸脱硫反应器中的总碱度大部分以Ac~-碱度形式存在,但反应体系的缓冲能力由H_2CO_3/HCO_3~-控制;进水碱度控制在300～500 mg/L,对于反应体系碱度的平衡与调节是必要的。

Stabilization and control of alkalinity during sulfate-reduction

Continuous-flow test was conducted in an acidogenic sulfate-reducing reactor supplied with sulfate- laden wastewater to investigate the stabilization and control of alkalinity during sulfate reduction. When the highest sulfate removal rate was achieved at different experimental stages and was maintained at a stable level, the following issues were discussed: the constitution of total alkalinity and its calculation, the effect of volatile fatty acid (VFA) and pH value on the stability of alkalinity, and the conversion of different kinds of alkalini- ty. The experimental results showed that alkalinity increased during sulfate-reduction, and different form of al- kalinity could convert each other to a certain. The constitution of total alkalinity was closely related to pH val- ue. Sulfate removal rate and the value of alkalinity could reach the highest level with pH of 6.0~6.2. Most of the alkalinity in acidogenic sulfate-reducing reactor existed in the form of Ac~--alkalinity but the cushion capa- bility was controlled under the balance of H_2CO_3/HCO_3~-. 300 ~ 500 mg/L alkalinity in influent was necessa- ry for the balance and adjustment of alkalinity in such a reactor.