The reason is that when production accidents occur in these factories, a large amount of organic wastewater with high concentration and large pH fluctuation will be discharged in a short time. If these wastewater directly enters the sewage treatment system, it will bring high impact load to the running biological treatment system, and the impact will take a long time to recover, sometimes causing fatal injuries.
In order to avoid the influence of accident water on sewage treatment system, many sewage treatment plants have set up accident pools to store accident water.
Standard: When it is necessary to occupy the accident pool (such as the rain pool used in the early stage) in a non-accident state, the occupied volume shall not exceed 1/3 of the volume of the accident pool, and technical measures for emergency evacuation shall be provided. The sewage treatment accident pool cannot be used as an accident storage facility, and the risk cannot be further transferred to the sewage treatment system.
Extended data
The capacity of the emergency pool should be comprehensively determined according to the equipment capacity of the accident place, the fire water consumption at the time of the accident and the precipitation that may enter the emergency pool. The internal volume of the fire dike in the tank farm, the volume of the drainage pipeline discharged to the accident pool below the highest liquid level of the self-flowing water accident pool, and the volume of the existing drainage facilities for storing accident drainage can all be used as the effective storage volume of accident drainage.
When calculating the amount of accident wastewater, the accident in the device area or storage tank area is not considered at the same time, and the maximum value is taken. The drainage capacity of the emergency drainage collection system should be checked according to the maximum flow of emergency drainage, and the measures of fire prevention, explosion prevention, seepage prevention, corrosion prevention, freezing prevention, flood control, anti-floating and earthquake resistance of the drainage system should be defined.
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