Sodium hypochlorite Dosing System

Product Introduction
Chlorination disinfection is an important part of water quality control in water treatment plants. The amount of chlorine added to water during disinfection can be divided into two parts, namely the required chlorine amount and residual chlorine. For the process of drinking water, the amount of chlorine consumed after adding chlorine to the raw water for a certain period of time to inactivate microorganisms, oxidize organic matter, and reduce substances in the water is called the chlorine demand. In order to suppress the reproduction of residual microorganisms in water, a small amount of residual chlorine needs to be maintained in the pipeline network.

Details
The hygiene standards for drinking water in our country stipulate that the residual free gas in the factory water should not be less than 0.3mg after 30 minutes of contact, and not less than 0.05mg at the end of the pipeline network. Although the residual gas of the latter still has disinfection ability, it is still insufficient for disinfection of re contamination and can serve as a signal indicating re contamination. This is particularly important for long branched pipe networks with stagnant water ends. When disinfecting with chlorine, the gas injection should generally meet the required chlorine consumption to kill bacteria and achieve the specified disinfection indicators, as well as the residual chlorine required to inhibit the reproduction of residual pathogenic bacteria in water. At the same time, excessive dosage can easily produce carcinogens such as trichloromethane and tetrachloromethane. Therefore, it is crucial to correctly control the amount of gas added during the water treatment process.

Main configuration:
（1） Dosing device
Purpose: Online monitoring and control of residual chlorine, automatic addition of sodium hypochlorite
Basic configuration of each set of dosing equipment:
(1) Electromagnetic driven flow range of metering pump 2-20L/h pressure:> 0.6MPa
(2) The medicine box has a capacity of 100-3000L and is equipped with a liquid level lower limit switch
(3) Flow meter ultrasonic/open channel flow meter signal output 4-20mA or 0-10V
(4) Residual gas probe measurement range 0-10ppm accuracy 0.01ppm signal output 4-20mA or 0-10V
Control rules:
According to the combined control of sewage flow rate and residual gas value at the outlet, adjust the dosage of sodium hypochlorite, and superimpose the signals to achieve the maximum dosage.
（2） Control box
Purpose: Automated operation of the entire equipment, including:
(1) Current traffic value display
(2) Current residual chlorine value display
(3) Control the dosage of sodium hypochlorite based on the composite of sewage flow rate and residual gas value at the outlet
(4) Bottom limit alarm of medicine box liquid level, automatic pump stop
(5) Manual automatic operation conversion