On the evening of July 12, Fuxin City held a press conference to inform about the flash explosion accident in the sewage treatment plant of the fluorine industrial development zone on July 11.
It was introduced at the press conference that the accident investigation team has been formed at the provincial, municipal and county levels, and relevant experts have entered the site to carry out accident investigation. The scene of the accident was effectively controlled, the injured people were effectively treated, and the accident investigation and aftermath handling work is proceeding in an orderly manner. After the accident, the Fuxin Emergency Medical Rescue Center urgently dispatched ambulances and medical personnel to the scene to rescue. Up to now, a total of 88 people have been admitted, 66 people have been steadily discharged, 2 people were slightly injured, and the remaining 20 people were hospitalized for observation.
According to the guidance of the Liaoning Provincial Working Group, the park has been completely shut down for rectification, eliminating hidden risks, improving safety and environmental protection facilities, and ensuring the sustainable, stable and high-quality development of the park.
In addition, after monitoring by the environmental department, the accident did not affect the surrounding atmospheric environment or the water quality of the Xihe River. The air quality in Fuxin City met the standard requirements.
Liu Ning, deputy secretary of the Liaoning Provincial Party Committee and acting governor, emphasized:
"Don't bring bloody GDP, don't pollute GDP, and strive to promote green and high-quality development."
This is not the first time an explosion has occurred in a sewage treatment plant. Similar incidents have occurred in the past few years.
On May 9, 2018, a sewage treatment plant in Nanning, Guangxi fired due to the leakage of chemical chlorine tablets
On May 22, 2016, an explosion occurred in Nancheng Sewage Treatment Plant in Binzhou High-tech Zone, Shandong, slightly injuring 3 people
On October 16, 2019, an explosion occurred in a sewage treatment plant in the cooperative area of Hunchun City, Jilin Province
On December 23, 2017, the anaerobic tank of the sewage treatment plant under construction in Wanding, Yunnan suddenly exploded, and 4 workers died on the spot
Why did the sewage treatment plant explode?
Although the official investigation has not been concluded and no definitive conclusions have been reached, industry experts believe that the explosion in the hydrolytic acidification workshop of the sewage treatment plant in the Fuxin Fluorine Industry Development Zone is likely to be due to the accumulation of flammable exhaust gas in the closed workshop and the concentration reached the explosion limit. Open flames or electric sparks cause detonation.
Hydrolysis acidification is the process of using microbial fermentation to hydrolyze insoluble organic matter in water into soluble organic matter, and convert difficult-to-degradable macromolecules into easily-degradable small molecules, thereby improving the water quality of sewage. During this fermentation process, flammable gases (such as methane) will be generated, and if not handled properly, it may explode.
Yang Bin, chairman of Beijing Jinkong Data Technology Co., Ltd., said, "Many gases will be generated during the disposal of sewage treatment plants. The main components produced in each process may be different, but most of them are flammable organic substances, such as methane. , Carbon monoxide and hydrogen sulfide." In this case, the workshop must have ventilation facilities and good ventilation.
Yang Bin pointed out that, in particular, there are several technological links that need more attention:
The first is the pretreatment workshop, where the sewage has just come in and the organic content is high.
The second is the sludge disposal workshop, which is the workshop with the highest sludge organic content.
The third is anaerobic treatment workshops. Some sewage treatment plants with high sewage concentration may use anaerobic processes. This workshop mainly produces biogas, which is most likely to explode. Many advanced sewage treatment plants also collect and use biogas, which is more necessary to ensure safety. These are all dangerous places in the process section. "
"Explosion is the first danger, and the second danger is poisoning." Yang Bin said that whether it is carbon monoxide or hydrogen sulfide gas, there are many cases of poisoning throughout the country every year, "And in the accidents exposed, many cases are after a person is poisoned. , Other people participated in the rescue, but the security awareness was not enough, they went in directly and fell down."
"Another hazard is corrosion. The organic gases produced by sewage treatment plants are very corrosive. This corrosion is mainly to the equipment. Even if the corrosiveness of the gas did not affect the personal safety at the time, if the treatment is not good, yes The impact of equipment will also lead to accidents or losses in production safety."
From the source of the explosion, the organic gas produced by the sewage treatment plant must be monitored, and it is necessary to conduct regular inspections and discover or predict such accidents in advance. If a gas sensor is installed, it will alarm if the gas leaks or reaches a certain concentration.
The second is the normative operation. When entering a confined space, the standard approach is to take a gas detection instrument to test the concentration and leave it open for a certain period of time before the worker can go in for operations.
From the manufacturers themselves, one is the need to increase investment in environmental protection facilities, the second is more standardized management, and the third is strict implementation of national and industry standards.
"Sewage treatment plants should focus on monitoring, treatment and disposal as a focus of work. It may not see any economic benefits in the short term, but it is still necessary to invest in the long term." Yang Bin said.
