接种物对厌氧同步脱硫反硝化特性的影响实验研究

分别以厌氧污泥、脱氮硫杆菌菌悬液和厌氧污泥并添加脱氮硫杆菌菌悬液为接种物,以硫化物和硝酸盐为进水基质,考察不同接种物条件下,各反应器的硫化物氧化特性、反硝化特性、生化反应机理及微生物特性。结果表明,在无菌条件下,硫化物不能被硝酸盐化学氧化。接种脱氮硫杆菌菌悬液的2#反应器的硫氧化速率为1.98 g S/(m3.h),停留24 h硫化物的去除率高达97%,脱硫能力最强,该接种条件下以硝酸盐氧化硫化物为主反应,优势菌为杆菌,进水的NO3--N/S应控制在0.4以下,可以实现高效生物脱硫。接种厌氧污泥的1#和3#反应器的脱氮效果比2#反应器好,停留时间为24 h时,硝酸盐的平均去除率为96%。单独接种厌氧污泥的1#反应器的硫氧化速率为1.78 g S/(m3.h),其优势菌为球菌,该接种条件下以硝酸盐氧化硫化物和硝酸盐氧化单质硫为主反应,进水的NO3--N/S应控制在0.8左右。以厌氧污泥联合脱氮硫杆菌为接种物时,硫氧化速率为1.71 g S/(m3.h),反应器以硝酸盐氧化硫化物、硝酸盐氧化单质硫以及异养反硝化为主反应,驯化后优势菌为球形、卵圆形和短杆状,应控制进水NO3--N/S为1.2,可以实现同步脱硫反硝化,该工艺既可以用于含硫废水的处理,也可以用于C/N低的硝酸盐废水的处理。

Effect of inoculum on process of simultaneous desulfurization and denitrification

In this experiment,three reactors were inoculated respectively with anaerobic sludge,pure culture of Thiobacillus denitrificans and mixture of anaerobic sludge with pure culture of Thiobacillus denitrificans ander influent of sulfide and nitrate conditions.This study investigated the characteristics of sulphide oxidizing,denitrifying.mechanism of biological reaction,and microbiological characteristics under difierent inoculum conditions.The results showed that under aseptic conditions,chemical oxidation of the sulfide by nitrate is either non-existing or occurring at a very low rate.Biological oxidation rates of sulfide is 1.98 g S/(m~3·h)in 2# reactor inoculated with pure culture of Thiobacillus denitrificans.and the removal efficiency of sulfide is 97%after 24 hours.Biological oxidation of the sulfide by nitrate was main mechanism in 2# reactor,in which short rods bacterium predominated,and highly sulfide removal was achieved at NO_3~--N/S ratio of 0.4.Biological oxidation rates of sulfide was 1.78 g S/(m~3·h) in l# reactor inoculated with anaerobic sludge.Both of biological oxidation of the sulfide by nitrate and biological oxidation of the sulfur by nitrate are main mechanisms in 1# reactor,in which coccus bacterium predominated,and highly sulfide removal was achieved at NO_3~--N/S ratio of 0.8.Biological oxidation rates of sulfide was 1.71 g S/(m~3·h) in 3# reactor inoculated with mixture of anaerobic sludge with pure culture of Thiobacillus denitrificans.All of biological oxidation of the sulfide by nitrate,biological oxidation of the sulfur by nitrate and heterotrophic denitrification happened in 3# reactor,in which short rods and coccus bacterium predominated,and complete nitrate and sulfide removal was achieved at NO_3~--N/S ratio of 1.2.In addition,the process can be applied for wastewater containing sulfide as well as wastewater containing nitrate with low C/N ratio.