Experimental Study On In-situ Restoration That Is In The Channel Of Black Odorous River By Compound Microorganism

In order to explore the in-situ restoration technology of the bottom mud of the city's black and smelly rivers,the water body and the bottom mud of the Dongmen to Chaoyang Gate section of Xi'an Moat were studied,and the black and smelly rivers were simulated and repaired using compound microbiological agents.The aim of this paper is to explore the in situ remediation technology which is suitable for the contaminated bottom mud of black and smelly rivers,and to provide theoretical support and reference for the management of black and smelly rivers in cities.In order to explore the water quality conditions that form black odor in water bodies.This study first assessed the status quo of the black and smelly water bodies in the Dongmen to Chaoyang Gate section of Xi'an Moat,and determined the black and smelly levels of the water bodies.Secondly,through the continuous monitoring of the water quality of the test section from May to August 2017,data analysis was conducted.Using the color threshold?CH?as the black odor index,DO,COD,NH₃-N,TP,pH,and total iron and black odor indicators were selected for correlation studies.It can be concluded that the relationship between black odor and COD,NH₃-N,TN,and TP in the Dongmen-Chaoyang Gate section of Xi'an Moat is relatively large.In subsequent repair experiments,COD,NH₃-N,TN,TP were selected to determine the repair effect of the evaluation index factors.In the experiment of repairing the bottom mud of the black and smelly river,the exploration experiment of the best microbial agent was found:For the upper covering water,the removal rate of COD,NH₃-N,TP,and TN of the water body was 2.5mL/L.The highest,They were 72.8%,84%,81.6%and 86.4%respectively.For bottom mud,when the amount of addition is 2mL/L,the bottom mud repair effect is the best,and the growth rates of bottom mud reduction,bottom mud organic matter content,and biodegradation capacity are 7.8cm,36.9%,and 342%,respectively;Through temperature and dissolved oxygen experiments,the optimum temperature is 20³0°C,and the optimal dissolved oxygen content is 9mg/L.Under this condition,the repair effect is best.In the experiment of repairing the bottom mud of the black and smelly river in the dominant bacteria pair test section,the experimental results showed that when the amount of lactococcus lactate was 2mL/L,the thickness of the bottom mud was the largest,6.3cm,and the removal rate of organic matter content was the best,which was 29.8%.Biodegradability also increased the most,at 230%;The removal rates of COD,NH₃-N,TP,and TN in overburden water were the largest,with 62.5%,78%,75.7%,and79.8%,respectively.When the amount of Bacillus subtilis was 2.5mL/L,the thickness of the bottom mud was The largest,5.8cm;The organic matter content has the best removal rate,reaching a maximum of 25.9%,while the bottom mud has the strongest biodegradability,reaching 229%;When the amount of injection was 2mL/L,COD,NH₃-N,TN,and TP in the overburden had the best removal effects,and the removal rates reached58.7%,74%,74.4%,and75.6%,respectively.According to the repair effect of the two bacteria,the treatment effect of Lactococcus lactate is better than that of Bacillus subtilis,and the treatment effect of the two bacteria alone is worse than that of the compound microorganism.The results show that the treatment effect of compound microorganism is better than that of single microorganism.