Water quality analysis
Water quality analysis is mainly used in domestic water, industrial water source detection and drainage detection. In domestic drinking water, water quality analysis is based on drinking water standards to ensure the safety of drinking water for residents. In industrial water, in order to meet the requirements of the industrial water treatment system, it is necessary to analyze the corresponding water source to ensure the stable operation of the water treatment system. At the same time, for reasons such as environmental protection, we should also test industrial drainage to meet environmental protection requirements.
Scope of water quality testing
Sewage, pure water, sea water, fishery water, swimming pool water, reclaimed water, bottled pure water, drinking natural mineral water, cooling water, farmland irrigation water, landscape water, domestic drinking water, ground water, boiler water, surface water, industrial water, Test water, etc.
The purpose of water quality analysis
For drinking water, the main consideration is the impact on human health. In addition to physical and chemical indicators, the water quality standards also include microbiological indicators. For industrial water, whether it affects product quality or is easy to damage containers and pipelines is considered.
Water quality analysis related indicators
Chromaticity: Most people can perceive the chromaticity of drinking water if it is greater than 15 degrees, and people feel disgusted when it is greater than 30 degrees. The standard stipulates that the color of drinking water should not exceed 15 degrees.
Turbidity: an expression for the optical properties of water samples. It is used to express the degree of clarity and turbidity of water. It is one of the most important indicators to measure the quality of water. It is also used to assess the purification efficiency of water treatment equipment and evaluate the status of water treatment technology. important basis. The reduction of turbidity means that the content of organic matter, bacteria, viruses and other microorganisms in the water body is reduced, which not only improves the disinfection and sterilization effect, but also helps to reduce the production of halogenated organic matter.
Odor and taste: Water odor is mainly due to the presence of organic matter, which may be caused by increased biological activity or industrial pollution. Changes in the normal odor of public water supplies may be a sign of changes in raw water quality or inadequate water treatment.
Objects visible to the naked eye: mainly refers to particles or other suspended matter present in water that can be observed with the naked eye.
Residual chlorine: Residual chlorine refers to the amount of chlorine remaining in the water after chlorine disinfection and contact for a certain period of time. The continuous sterilization ability in water can prevent the self-pollution of water supply pipelines and ensure the quality of water supply.
Chemical oxygen demand: refers to the amount of oxygen required by chemical oxidants to oxidize organic pollutants in water. The higher the chemical oxygen demand, the more organic pollutants are in the water. Organic pollutants in water mainly come from the discharge of domestic sewage or industrial wastewater, and are produced by the decay and decomposition of animals and plants and then flow into water bodies.
Total number of bacteria: Bacteria contained in water come from air, soil, sewage, garbage and dead animals and plants. There are many types of bacteria in water, including pathogenic bacteria. The standard for drinking water in my country is that the total number of bacteria in 1 ml of water should not exceed 100.
Total coliforms: It is an indicator of fecal pollution. The detection of it can indicate whether there is fecal pollution in the water and the degree of pollution. In the water purification process, after disinfection treatment, if the total coliform index can meet the requirements of drinking water standards, it means that other pathogenic bacteria have also been basically killed. The standard is no more than 3/L in the test.
Heat-resistant coliforms: It reflects the degree of contamination of food by human and animal feces more closely than coliforms, and is also an indicator of fecal contamination in water bodies.