The national standard "Guidelines for Water Reuse" jointly formulated by Litong Water, Tsinghua University, China Institute of Standardization, etc. will be officially implemented on July 1, 2022.
What are the main elements of this standard?
The Guidelines for Water Reuse Recycled Water Classification (GB/T 41018-2021) are applicable to the classification of reclaimed water in urban reclaimed water allocation, safety management, benefit evaluation, reclaimed water statistics and labeling.
The standard stipulates the secondary treatment, tertiary treatment and advanced treatment specifications for urban sewage. Secondary treatment is the basis of reclaimed water treatment, tertiary treatment or advanced treatment is the main unit of reclaimed water treatment, and disinfection process is an essential unit of reclaimed water treatment. Secondary treatment is the process of removing colloids, dissolved organic compounds and pollutants such as nitrogen and phosphorus from sewage by biological treatment and other methods. Tertiary treatment is the process of further removing pollutants from sewage on the basis of secondary treatment. Advanced treatment is based on tertiary treatment, further strengthening the water purification process of inorganic ions, trace amounts of toxic and harmful pollutants and general dissolved organic pollutants.
According to the sewage regeneration treatment process and water quality requirements, the standard is divided into three levels of A, B and C and 10 subdivided levels according to the use of reclaimed water.
The water quality control projects of 10 sub-levels in the three levels of reclaimed water are as follows:
The concentration levels of the main water quality indexes of the effluent from each typical treatment process are shown in the following table:
epilogue
The national standard (GB/T 41018-2021) of the "Guidelines for Water Reuse" stipulates the classification of reclaimed water and its basic basis for the first time, provides a scientific and systematic basis for the classification of reclaimed water in urban reclaimed water utilization planning, safety management, benefit evaluation, reclaimed water statistics and labeling, etc., promotes the specialization and standardization of the recycled water industry in the mainland, strengthens the classification management of reclaimed water in the mainland, and promotes the rapid development of the reclaimed water industry.