Core technology:
Efficient disinfection revolution of electrolyzed salt water The sodium hypochlorite generator generates sodium hypochlorite (NaClO) on-site by electrolyzing salt water (NaCl solution). Its core chemical reaction formula is: \(\text{NaCl} + \text{H}_2\text{O} + \text{electric energy} \rightarrow \text{NaClO} + \text{H}_2↑\)
Under the action of the DC electric field, the anode chloride ions (Cl⁻) are oxidized to chlorine gas (Cl₂), and the cathode water decomposes to produce hydrogen gas (H₂) and hydroxide ions (OH⁻). Finally, the chlorine gas reacts with sodium hydroxide (NaOH) to generate sodium hypochlorite. The current efficiency of the advanced system can reach more than 85%, and only 1.323 amperes of current are consumed for each gram of effective chlorine generated. The technology types are mainly divided into two categories: membrane electrolysis can produce 12.5% high-concentration solution, which is suitable for industrial bleaching; membraneless electrolysis generates 0.8%-1% low-corrosive solution through vertical multi-electrolyzer design, and the maintenance cost is reduced by 30%. Key components include titanium alloy electrolyzer (lifespan 3-5 years), high-frequency constant current power supply (conversion efficiency> 95%) and PLC control system, some of which support remote monitoring function. 2. Application scenario: from municipal water supply to industrial circulating water Municipal drinking water treatment: Sodium hypochlorite generator generates 0.8% solution by electrolyzing brine, which can effectively kill pathogens such as Escherichia coli and meet the "Sanitary Standards for Drinking Water" (GB5749-2022).
Taking medium-sized equipment as an example, thousands of cubic meters of groundwater can be treated per hour to meet the city-level water supply needs. Sewage treatment: In hospital sewage, sodium hypochlorite can inactivate viruses, and the discharged water quality meets the "Medical Institution Water Pollutant Discharge Standard" (GB18466-2005). After a sewage treatment plant adopted the equipment, the removal rates of ammonia nitrogen and COD reached 75% and 60% respectively. Industrial circulating water: Electrolysis of seawater to generate sodium hypochlorite can prevent biological fouling of cooling water pipelines, replace traditional chlorine-containing agents, and reduce the risk of equipment corrosion. The application case of a power plant shows that the annual maintenance cost is significantly reduced. Food processing and medical treatment: 0.8%-1% solution is used for equipment cleaning, which complies with the HACCP system; 100-300ppm solution is sprayed to disinfect the hospital environment, and the virus inactivation efficiency is >99.9%.
Application scenarios: from municipal water supply to industrial circulating water
Municipal drinking water treatment:
The sodium hypochlorite generator generates a 0.8% solution by electrolyzing salt water, which can effectively kill pathogens such as Escherichia coli and meet the "Sanitary Standards for Drinking Water" (GB5749-2022). Taking medium-sized equipment as an example, it can treat thousands of cubic meters of groundwater per hour to meet the city-level water supply needs.
Sewage treatment:
In hospital sewage, sodium hypochlorite can inactivate viruses, and the discharged water quality meets the "Medical Institution Water Pollutant Discharge Standard" (GB18466-2005). After a sewage treatment plant adopted the equipment, the ammonia nitrogen and COD removal rates reached 75% and 60% respectively.
Industrial circulating water:
The electrolysis of seawater to generate sodium hypochlorite can prevent biological fouling of cooling water pipelines, replace traditional chlorine-containing agents, and reduce the risk of equipment corrosion. The application case of a power plant shows that the annual maintenance cost has been significantly reduced.
Food processing and medical treatment:
0.8%-1% solution is used for equipment cleaning, in compliance with the HACCP system; 100-300ppm solution is sprayed to disinfect the hospital environment, with a virus inactivation efficiency of >99.9%.
Environmental advantages: zero transportation risk and low carbon emissions
Deep protection of safety design
The safety advantage of the on-site preparation system is not only reflected in the risk avoidance of the transportation link, but also throughout the entire process of equipment operation. The chemical stability of low-concentration sodium hypochlorite solution (0.8%-1%) greatly reduces the storage risk - its corrosiveness is only 1/5 of that of high-concentration products, and it can be directly stored in ordinary PVC storage tanks without special anti-corrosion treatment. The system's built-in multiple safety interlock mechanism further improves reliability: when the temperature of the electrolyzer exceeds 60°C, the cooling system is automatically triggered; when the hydrogen concentration monitoring device detects a volume ratio of more than 1%, it immediately cuts off the power supply and starts forced exhaust to ensure that hydrogen is always below the explosion limit (4%-75%). At the operational level, the human-machine interaction interface adopts an anti-mistaken touch design, and the adjustment of key parameters requires dual authorization. With the remote start and stop function, the frequency of direct contact between personnel and chemicals is reduced, and the operating accident rate is reduced by more than 90% compared with the traditional outsourcing model.
Full-chain innovation of low-carbon technology
The carbon reduction effect of base substitution is more significant in large-scale applications. Taking a water plant that processes 50,000 tons per day as an example, the use of an on-site preparation system can reduce the transportation volume of sodium hypochlorite by about 14,000 tons per year, which is equivalent to reducing the carbon emissions of 300 heavy trucks (about 22kgCO₂ per truck). On the technical level, the new high-frequency switching power supply reduces the energy consumption of electrolysis to below 3.8kWh/kg effective chlorine, which saves 12% energy compared with the traditional industrial frequency power supply; the coupled waste heat recovery device can use the heat energy generated during the electrolysis process to preheat the brine, and can still maintain an electrolysis efficiency of more than 85% when the ambient temperature is below 10°C. In the low-carbon certification system, the carbon footprint of equipment that meets the EU EMAS ecological management standards can be included in the company's ESG report, becoming an important plus for green factory certification, especially in industries with strict environmental protection requirements such as food processing and pharmaceuticals. This low-carbon attribute has become a key indicator for supply chain access.
Systematic construction of resource circulation
The closed-loop resource characteristics of the electrolysis system are reflected in the full-cycle control of material flow. The brine preparation process uses a precise ratio of softened water and refined salt. The sodium chloride that does not participate in the reaction can be returned to the electrolytic cell through a circulation pump, and the raw material utilization rate is increased to more than 98%, avoiding the 3%-5% waste of reagents in the traditional dosing method. For high-concentration preparation processes (12%-15%), the by-product sodium hydroxide can be simultaneously recovered to adjust the pH value of the water body, realizing the resource synergy of "one electricity and two productions". In the industrial symbiosis scenario, the low-concentration sodium hypochlorite produced by the system can be directly used for factory sewage treatment, and the treated reclaimed water is fed back to the brine preparation, forming a "salt-electricity-water" circulation chain. This model not only meets the requirements of the ISO 14001 environmental management system, but also brings economic benefits to enterprises by reducing the cost of water treatment by 0.3 yuan per ton. When applied in large water-consuming enterprises such as papermaking and printing and dyeing, the annual cost savings can reach millions of yuan.
Market dynamics: Intelligence and renewable energy drive growth
The global sodium hypochlorite generator market has an annual growth rate of about 7%-9%. The Chinese market size is expected to exceed 1.5 billion yuan in 2024, with sewage treatment and municipal water supply as the main growth points. Technology upgrade directions include:
Intelligent control:
Integrated AI algorithm predicts salt consumption and electrolysis efficiency, and advanced control systems can adjust parameters in real time, reducing energy consumption by 15%-20%.
Renewable energy integration:
Solar-powered electrolysis systems (such as small water plants in remote areas) further reduce operating costs and reduce grid dependence. A certain island project uses photovoltaic power supply, which saves significant electricity bills annually.
High current density technology:
The new ruthenium-iridium coated electrode supports a current density of 10kA/m², and the production capacity is increased to twice that of traditional systems. For example, only 4 kWh of electricity is consumed per kilogram of effective chlorine.
Operation and maintenance: the key to extending equipment life
Raw material management:
Use refined industrial salt (purity> 99.5%) and monitor the brine concentration (3%-5%) through an online conductivity meter. High-hardness water needs to be pre-treated and softened (hardness < 10ppm) to avoid electrode scaling.
Equipment maintenance:
The electrolytic cell is pickled (1%-3% hydrochloric acid) every quarter to remove calcium scale, and the power module is checked for cooling fans every year. Through automatic pickling technology, the electrode maintenance cycle is extended from once a month to once a quarter, and labor costs are reduced by 50%.
Safe operation:
The hydrogen discharge port must be away from fire sources and equipped with a dilution fan. The system is usually equipped with a hydrogen monitoring device, which automatically shuts down when the concentration exceeds the standard. Operators need to wear goggles and acid-resistant gloves to avoid direct contact with the electrolyte.
Future trends: from technological breakthroughs to regulatory compliance
Technological innovation:
Ultra-pure sodium hypochlorite: products with impurities <1ppm are used for semiconductor wafer cleaning, replacing imported chemicals, and reducing the annual procurement cost of an electronics factory by 40%.
Low-temperature solution: A 30-40℃ constant temperature water tank is configured in the northern region to ensure electrolysis efficiency. A winter application case of a water plant shows that the yield is stable at more than 95% of the design value.
Regulatory drive:
The EU CLP regulation requires that the sodium hypochlorite solution label clearly classifies hazards and promotes equipment upgrades. Generators certified by NSF/ANSI/CAN 61 can be directly used for drinking water treatment to meet North American regulatory requirements.
Emerging markets:
Demand in developing countries has grown significantly. For example, the procurement case in Afghanistan shows that the equipment successfully ensures the safety of household drinking water. It is expected that the annual growth rate of the Asia-Pacific market will reach 9% from 2025 to 2032, with India and Southeast Asia as the main growth points.
