The tax rate of water treatment fittings is calculated by dividing the actual tax paid by the current tax-free income.

Sewage treatment (wastewater treatment): the process of purifying sewage to meet the water quality requirements for discharge into a certain water body or reuse.

Sewage treatment is widely used in construction, agriculture, transportation, energy, petrochemical, environmental protection, urban landscape, medical treatment, catering and other fields, and it has also entered the daily life of ordinary people more and more.

The topic of water pollution is constantly being raised, especially groundwater pollution. Farmers or entrepreneurs in Hangzhou, Wenzhou and other places in Zhejiang have invited environmental protection directors to swim in the river in order to attract everyone's attention to the seriousness of water pollution.

Although all environmental protection directors have chosen silence or refusal, people's awareness of environmental protection has awakened and their concern for water pollution has reached an unprecedented level.