1. Close the inlet valve of sewage tank, cut off the inlet water source, solve the problem of temporary drainage during construction, and put up a sign;

2. The sewage pool is a closed space. For safety reasons, ventilation should be done well in advance to ensure foolproof.

3. Discharge the sewage in the sewage pool;

4. Dilute the sludge. Use a high-pressure pump to dilute the sludge. Clean up the silt and sundries at the bottom of the pool.

5. Rinse with clean water and take it out in time until it is clean;

6. Before the sludge is diluted, wash it repeatedly with a dirt suction truck. After the sludge is diluted, start the sewage suction equipment, suck the sludge out through the pipeline and put it into the prepared mud truck for transportation. Avoid secondary pollution to the environment.

7. Restore the use of the sewage tank and check whether the related equipment and valves are normal.