In order to maintain the effect of killing bacteria, the amount of residual chlorine
in the effluent should always be kept at 0.5-1 mg/l, and the residual chlorine at the end of the water supply pipe network should also be kept at 0.05-0.1 mg/l. An instrument that measures the amount of free chlorine remaining in effluent water is called a chlorine analyzer
. The online residual chlorine analyzer is used in the following places: ①On-line monitoring of residual chlorine content in water plant effluent; ②On-line monitoring of residual chlorine content in sewage treatment plant effluent; ③On-line monitoring of residual chlorine content in circulating cooling water; ④Boiler On-line monitoring of residual chlorine content in feed water treatment. When the online residual chlorine analyzer uses sterilized tap water as boiler feed water for desalination treatment, the residual chlorine in the tap water must be removed. Because the presence of residual chlorine will destroy the structure of the ion exchange resin, making its strength worse and easily broken. Free chlorine - Chlorine gas generates hclo and clo- in water, and the sum of hclo and clo- is called 'free chlorine'. Among them, free chlorine has a strong killing effect on bacteria and other microorganisms, and is an effective anti-virus component in free chlorine, so hclo is also called 'effective free chlorine'. Combined chlorine—Before the free chlorine plays a bactericidal role, since there are various impurities such as ammonium ions and organic substances dissolved in the water, these impurities will first react with the free chlorine and consume a part of the free chlorine. For example, free chlorine quickly reacts with ammonium ions in solution to form monochloramine and dichloramine. Over a longer period of time, free chlorine also reacts with organic compounds (such as proteins and amino acids) to form various organochlorine compounds. Chloramines and organochlorine compounds together are called combined chlorine. Total chlorine—combined chlorine plus free chlorine is the total chlorine in the solution, called total chlorine. Among these substances, only free chlorine is an effective disinfectant, and combined chlorine has almost no killing ability. Only when the above-mentioned chlorine consumption needs are met, there will be excess free chlorine to kill bacteria. Chlorine addition—the amount of chlorine added during chlorination disinfection is called chlorine addition, and the amount of chlorine addition should include two parts: chlorine demand and residual chlorine. Chlorine demand refers to the amount of chlorine required to kill bacteria and oxidize organic and reducing substances. The amount of residual chlorine - refers to the amount of chlorine remaining in the water to inhibit the re-reproduction of residual bacteria in the water, called residual chlorine or residual chlorine. Some people refer to free chlorine as residual chlorine, which is not accurate, and the remaining free chlorine after killing bacteria is residual chlorine. Factors affecting the detection of residual chlorine 1 Water sample 1.1 The pH value of the sample water The pH value of the sample water has a great influence on the measurement of short chlorine, especially when the pH value is less than 5 or greater than 10 (as shown in Figure 1), therefore, In practical applications, try to avoid using it within this range. 1.2 Temperature of sample water The temperature of sample water has certain influence on the measurement of residual chlorine. It is generally believed that the measured value will increase by about 5% for every 1 C increase in temperature. The ideal water sample temperature should be between 15 and 20 °C. The influence of water sample temperature on the measurement can also be seen in Figure 1. 1.3 Ammonium Chlorine Concentration of Sample Water In actual application, it is sometimes found that the amount of chlorine added increases, but the residual chlorine in the sample water decreases, and when it increases again, the residual chlorine increases again. This is what we often call breakpoint chlorine addition. Usually this is caused by the high concentration of ammonia nitrogen in the water, and the chemical reaction between gas and ammonia nitrogen in the water to produce chlorine ammonia. 3.1.4 Pressure and Flow Velocity If the pressure is too high and the flow velocity is too fast, the electrode will not respond in time and the measured value will be reduced. If the pressure is too small and the flow rate is too slow, the hypochlorous acid in the sample water will not be replenished in time and the sensitivity will be reduced. Generally, the flow rate of sample water is 0.5~1 L/min. The flow rate of 5~25 em/s is more suitable.
Collectively, the effect of water analyzer on industrial society has been to eliminate water quality monitoring device and drastically reduce the time long associated with water quality monitoring device.
Knowing these basics of is every essential. But if you don't know how to choose the proper for your specific need, let Shanghai Boqu Instrument Co., Ltd. experts be your guide. Enquire us at BOQU Water Quality Analyzer.
Once we have a good idea of how water analyzer can satisfy customer’s needs, consider whether we should create a skill for their demands.
comes in a vast array of styles and water quality monitoring device depending on which water quality monitoring deviceis used.
Shanghai Boqu Instrument Co., Ltd. will need to find one that fits our needs and budgets, and still turns out a quality product.