Drinking water

Water treatment involves a series of processes designed to remove or partially eliminate impurities from water, including organic and inorganic substances as well as microorganisms, to ensure the water meets relevant quality standards for its intended use. The core processes in drinking water treatment include coagulation, sedimentation, filtration, ozone-biological activated carbon treatment, disinfection, and chemical oxidation. Below is an overview of these core processes and their associated water quality monitoring requirements:

Process End

Coagulation

Sedimentation

Filtration

Application Description

Coagulation is currently the core process in water supply treatment, reclaimed water treatment, and partial sewage treatment. The process of adding coagulants to make colloidal substances and fine suspended solids in water that are difficult to settle naturally aggregate into larger particles for separation from water is called coagulation. Coagulation can remove turbidity and chroma, and also has a certain removal effect on inorganic and organic pollutants in water.
Coagulation process usually requires online monitoring of pH value and turbidity.

Product Selection

AL4030 Digital pH Sensor
AL4060 Digital Turbidity Sensor
AL4020 Spectroscopic On-line Water Quality Analyzer

Ozone-Biological Activated Carbon

Disinfection

The process of removing certain suspended particles from water by using their density greater than that of water is called sedimentation. Suspended solids with density greater than water may exist in raw water itself or be flocs generated by colloid coagulation. To evaluate the sedimentation effect, suspended solids or turbidity are usually monitored online at the outlet of the sedimentation tank. In addition, monitoring the sludge discharge concentration of the sedimentation tank is also conducive to mastering the operation status of the sedimentation tank.

The process of intercepting suspended solids and other impurities in water through the surface or filter layer of the filter medium is called filtration. Water after coagulation and sedimentation treatment usually needs to enter the filter for further reduction of suspended solid concentration or turbidity. Filtration can further reduce the suspended solid concentration or turbidity in water, create favorable conditions for subsequent treatment devices, and ensure the stable operation of subsequent treatment structures and the improvement of treatment effects.
To evaluate the filtration effect, turbidity of the filtered effluent is usually monitored online. In addition, monitoring the turbidity at the inlet of the filter can ensure stable effluent effect of the filter.

By combining ozone oxidation with activated carbon adsorption, the organic matter concentration in water can be reduced, macromolecular organic matter can be oxidized into small-molecular intermediate products, the biodegradability of pollutants can be improved, and the service life of activated carbon can be prolonged, which is widely used in the field of drinking water. At present, the ozone-biological activated carbon process has become one of the most effective methods for advanced treatment of drinking water.
To stabilize the operation of the ozone-biological activated carbon process, online monitoring of ozone in the effluent of the ozone contact tank is one of the effective methods to control the operation of the ozone process.

Water disinfection is to kill pathogenic microorganisms harmful to human health in water and prevent the spread of diseases through drinking water. There are many water disinfection methods, including chlorine and its compounds, ozone, chlorine dioxide, ultraviolet disinfection, or a combination of the above methods.
For the effluent of chlorination disinfection process, the disinfectant concentration is usually monitored online to ensure that a certain concentration of disinfectant remains in the water after disinfection treatment, so that it has continuous disinfection ability.

AL4060 Digital Turbidity Sensor
AL4140 Suspended Solids and Sludge Concentration On-line Sensor

AL4060 Digital Turbidity Sensor

AL4020 Spectroscopic On-line Water Quality Analyzer

For residual chlorine concentration monitoring, the following can be selected:
AL4020 Spectroscopic On-line Water Quality Analyzer (monitoring residual chlorine by spectroscopic method)
Or a dedicated residual chlorine sensor (such as AL series residual chlorine on-line analyzer, if available in the product library)