Free residual chlorine water treatment equipment articles
Residual chlorine refers to the amount of chlorine remaining in the water after being exposed to chlorine for a certain period of time when disinfecting with chlorine. (Water treatment equipment) Residual chlorine includes free residual chlorine and compound residual chlorine. Simple chlorine disinfection is currently commonly used in our country, so this indicator is clearly defined as free residual chlorine. In order to ensure the effectiveness of chlorine disinfection, the contact time after chlorination is also clearly specified. (Deionized water equipment)
The olfactory and taste threshold concentrations of free residual chlorine are both 0.2~0.5mg/, the olfactory threshold concentration of compound residual chlorine is 0.6~1mg/L, and the taste threshold concentration is 0.6~1.2mg/L
Experiments have proved that when the free residual chlorine is above 0.3mg/L and the contact effect is 30min, it can kill the intestinal pathogenic bacteria (such as typhoid, dysentery, etc.) Leptospira, Brucella, etc. Therefore, according to the requirements of epidemiology, it is stipulated that when chlorine is used for disinfection, the free residual chlorine should not be less than 0.3mg/L after 30 minutes of contact. (Water treatment equipment) If the chloramine disinfection method is used, the combined residual chlorine content should generally be more than twice the free residual chlorine, and the contact time should be no less than 2h. The specific value should be subject to the guaranteed disinfection effect. Enteroviruses (such as viral hepatitis, poliovirus, etc.) are more resistant to chlorine disinfectants than enteropathogenic bacteria.
According to reports, if the free residual chlorine is above 0.5mg/L and the contact time is 30~60min, (water treatment equipment) can also inactivate enterovirus. Therefore, when it is suspected that the water source may be contaminated by enterovirus, the chlorine disinfection dosage and contact time can be increased to ensure the safety of drinking water. The free residual chlorine in the tip water of the centralized water supply pipe network can be used as a signal for predicting whether there is re-pollution.