With the increasing attention of the state to environmental protection, the rural pit pond black smelly water management technology is gradually standardized, standardized, rural black smelly water occurs mainly due to a large number of exogenous organic matter discharged into the water body, instantly beyond the environmental capacity of the water body to accept the scope of the water body, the water body of dissolved oxygen is consumed by the microbial activity, and gradually from aerobic reaction to anaerobic reaction, the bottom sludge of the pit pond is anaerobic fermentation, resulting in the body of water stinks.

At present, the rural black smelly water body management methods are mainly divided into in situ restoration and ectopic restoration, ectopic restoration is mainly divided into two methods, one is to transport the sewage to the sewage treatment plant for treatment, the disadvantage is that the sewage transportation is difficult and high cost of treatment and difficult to be widely used. Another is the integrated sewage treatment station, the equipment solves the problem of sewage transportation, and treatment efficiency and speed, but the cost of treatment is still high, the maintenance of equipment during the treatment period and the treatment of pit and pond sludge is still a problem. Then there is in-situ restoration, which can be divided into physical, chemical and biological three kinds of restoration methods. Physical and chemical methods are usually paired, mainly using oxidizers and flocculants to reduce the eutrophication problem of the water body, curing the substrate, so as to repair the black-smelling water body, but the chemical agents are difficult to degrade, often producing secondary pollution of the water body, destroying the ecological balance of the water body, leading to recurrence. Microbial remediation is less expensive, easy to apply, and can reduce the degree of water pollution by improving the aquatic ecological environment and repairing the ecological balance. However, most microbial remediation technology is aerobic, anaerobic alternating treatment, need to set up aeration devices, and the process is complex, there are organic matter, total nitrogen degradation capacity is weak, the treatment efficiency is low, thus affecting the popularization and application of microbial remediation.

In May 2023, we received instructions from Secretary Wu of Gezhigang Township to treat the black smelly pit pond in front of Gezhigang Village Committee of Gezhigang Township, and our R&D Department received the instructions and then organized a site investigation in Gezhigang Village.

The investigation showed that the water quality deteriorated due to the inflow of livestock and poultry waste, the water body is yellow-green and malodorous, and the bottom mud floats, which has obvious impact on the daily activities of the surrounding residents, and the sampling and testing of the water quality ammonia nitrogen content of 39.54mg/L, total nitrogen of 55.67mg/L, the transparency of 7.5cm, and the dissolved oxygen is less than 1.0mg/L. The company's research and development department has been working on the treatment of the black stinking pit pond in front of the village committee of Gezhigang village.

Our company for the results of the survey, the pond many times sampling and testing, screening deodorization, putrefaction, water purification, oxygen type strains, after many debugging and compounding, prepared a type of pond can restore the quality of the microbial fungicide, and in June of the same year, on-site implementation of the use of the middle. 
After 3 times of adding bacterial agent, in early August of the same year to investigate again, the pond water quality improvement is obvious, the bottom mud is no longer floating, the odor disappeared, the water body was light yellow, collect samples for testing, water quality ammonia nitrogen content reduced to 18.2mg / L, transparency increased to 22.4cm. 
Sampling and testing on October 11, 2024, the water quality of ammonia nitrogen 7.73mg/L, transparency 32.8cm, dissolved oxygen 7.92mg/L. Refer to Table 1, the water body has been completely out of the category of black-odor water body.

Criteria for Grading the Degree of Pollution of Black-smelling Water Bodies

Water quality before treatment

In the process of governance

sprinkle fungicide

After the last splash of fungicide

Water surface condition at completion of treatment

Initial treatment control