There are some organic matter and a large number of pathogens in the pollutants contained in the sewage, but the bacteria and pathogens have the organic matter in the sewage as nutrition and cause a large number of reproduction, which will lead to the spread of infectious diseases! This chapter water quality online monitoring instrument manufacturers will work with you to understand the relevant knowledge of domestic sewage monitoring.

First, The Source of Domestic Sewage Hazards

1.Pathogen pollutants: mainly from urban life, hospitals, restaurants, communities and other sewage;

2.Pollution of organic matter: organic pollutants directly enter the water body, and decompose them into simple inorganic substances carbon dioxide and water through microbial chemistry;

3.Total phosphorus and ammonia nitrogen pollution: although nitrogen and phosphorus are indispensable elements of living organisms, if the content of such plant nutrients is too much, it will cause water pollution;

4.Strange smell: When there is a very strong strange smell in domestic sewage, it indicates that the water quality has been seriously polluted, not only pollute the water environment, but also have a certain impact on the lives of residents;

5.Elemental acid, alkali, salt pollution: acid and alkali pollution will make the PH value of the water body change, destroy its buffer rental, which will eliminate or inhibit the growth of microorganisms, and naturally affect the self-clean growth of the water body.

6.Increased hardness of groundwater.

Second, to Understand The Monitoring Standards of Domestic Sewage

“Comprehensive sewage discharge standard” GB8978-1996; Water Quality Standard for Sewage discharge into Urban Sewers CJ3082-99; Pollutant Discharge Standard for Urban Sewage Treatment Plants GB18918-2002;

Third, About Domestic Sewage Testing Items

Chemical oxygen demand (COD) : when the COD of the water body is high, it means that the water contains a large number of reducing substances, the higher the chemical oxygen demand, the more serious the organic pollution in the sewage. (The monitoring instrument is called “COD online analyzer“)

Biochemical oxygen demand: The aerobic microorganisms in the water will decompose organic matter in the water into inorganic matter at a certain temperature, and the dissolved oxygen in the oxidation process within a specific time, which represents a comprehensive indicator of the content of aerobic pollutants.

Suspended matter: It is a solid substance suspended in water, including organic matter, inorganic matter and mud sand insoluble in water. The content of suspended matter in water is an index used to measure water pollutants.

The total number of bacteria in sewage: refers to the total number of bacteria grown from sewage water samples after 24 hours of culture in nutrient AGAR at 37 degrees Celsius.

Monitoring of total phosphorus: The results of the determination of different forms of phosphorus into orthophosphate after digestion of water samples are calculated by the number of milligrams of phosphorus per liter of water samples. (The monitoring instrument is called “total phosphorus online analyzer“)

Escherichia coli: A group of bacteria associated with faecal contamination with certain characteristics that are not identical in biochemical and serum terms, mainly defined as: aerobic and facultative anaerobic, at 37 degrees Celsius can break down lactose, acid and gas production Gram-negative amblastobacteria. The instrument used to monitor it is called the Water Quality E. Coli Online Analyzer.