No matter in which industry the sewage is discharged, the pollutants contained in it are not single. Do you know the following sewage water quality indicators? If you want to know, please read on! It can be divided into the following three types:
Physical Indicators
Temperature, chroma, smell and taste, solid matter
There are three forms of solid matter: suspended, colloidal, and dissolved. For solid substances. Total solids (TS) is used as an indicator, and suspended solids (SS) is commonly used to represent the content of solid substances in sewage treatment.
Chemical Indicators
1) Chemical oxygen demand (CODcr) : refers to the amount of oxygen (mg/L) consumed by the oxidation of organic matter into CO2 and H2O under acidic conditions with a strengthening chemical oxidizer (China’s legal potassium dichromate), expressed by CODcr. The higher the chemical oxygen demand, the more organic pollutants in the water, the more serious the pollution.
2) Biochemical Oxygen demand (BOD5) : The amount of oxygen required when organic pollutants in water are decomposed by aerobic microorganisms is called biochemical oxygen demand (mg/L).
If the sewage composition is relatively stable, in general, CODcr> BOD5.
Generally BOD5/ CODcr is greater than 0.3, it is considered suitable for biochemical treatment.
3) Total oxygen demand (TOD) : the main elements of organic matter are C, H, O, N, S, etc., when the organic matter is all oxidized, CO2, H2O, NO, SO2, etc., at this time, the oxygen demand is called total oxygen demand (TOD).
4) Total organic carbon (TOC) : includes the carbon content of all organic pollutants in the water sample, and is also a comprehensive parameter for evaluating the organic substances in the water sample.
5) Total nitrogen (TN) : nitrogen compounds in sewage are divided into organic nitrogen, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, and the total amount of four nitrogen compounds is called total nitrogen (TN). Kjeldahl nitrogen (TKN) is the sum of organic nitrogen and ammonia nitrogen.
6) Total Phosphorus (TP) : including organic phosphorus and inorganic phosphorus two types.
7) pH value
8) Heavy Metals
Biological Indicators
1) Coliform number: The number of coliform bacteria contained in each liter of water sample, measured in units /L.
2) Total bacteria: The total number of coliform bacteria, pathogens, viruses and other bacteria, expressed by the total number of bacterial colonies per milliliter of water sample.
The above sewage water quality indicators, the occurrence of exceeding the standard will have an impact on the ecological cycle and human health, so the real-time online monitoring of these indicators to ensure the safety of water quality! Of course, the water quality monitoring instrument used for different indicators is also different. Hangzhou Modi is a professional manufacturer of water quality monitoring equipment, the main products are: COD online analyzer, total nitrogen online analyzer, total phosphorus online analyzer, water heavy metal online analyzer, Escherichia coli online analyzer, biological toxicity online analyzer, total residual chlorine online analyzer.
