At a time when ecological and environmental protection is receiving much attention, sewage treatment is essential for maintaining ecological balance and protecting human health. Sewage treatment plants bear the heavy responsibility of purifying water quality, and use a variety of technologies and agents to ensure that sewage is discharged in compliance with standards. Sodium hypochlorite plays a key role in this. The BSHH series sodium hypochlorite generator produced by Bluewav can safely and stably produce sodium hypochlorite by electrolyzing brine.
Sodium hypochlorite (NaClO) is a strong oxidant and is mainly used for disinfection and sterilization in sewage treatment. After being added to sewage, it will hydrolyze: NaClO + H_2O \rightleftharpoons NaOH + HClO. The generated hypochlorous acid is extremely unstable and highly oxidizing, which can destroy the biomacromolecule structures such as enzymes and proteins in microbial cells, making them inactive, thereby killing microorganisms and achieving the purpose of disinfection.
From the perspective of cost-effectiveness, the preparation process of sodium hypochlorite is simple, the raw material source is wide, and the cost is lower than that of disinfectants such as chlorine dioxide and liquid chlorine, which can help sewage treatment plants control operating costs. In terms of disinfection effect, it has a broad spectrum of sterilization, can quickly reduce the content of microorganisms in sewage, and ensure that the effluent water quality meets the health standards. In terms of safety, compared with highly toxic liquid chlorine, sodium hypochlorite is usually liquid or solid, not easy to volatilize, with low risk of leakage and safer operation.
In urban domestic sewage treatment plants, sodium hypochlorite is used in the deep treatment stage. The biologically treated sewage contains microorganisms. After adding sodium hypochlorite for disinfection, it can meet the discharge standards and is used for urban landscape water use, green irrigation, etc. In industrial wastewater treatment plants, such as food processing and pharmaceutical wastewater, after pretreatment and biochemical treatment, sodium hypochlorite can adapt to its water quality characteristics, remove harmful microorganisms, reduce biological toxicity, and achieve standard discharge or reuse.
Using liquid chlorine for disinfection, due to high safety risks and high management costs, sodium hypochlorite is used instead. Through operation monitoring, it is shown that the effluent water quality is stable and meets the standards, the disinfection effect is good, the operating cost is reduced, and the operation is safe and simple, reducing the risk of safety accidents.
Determining the dosage of sodium hypochlorite requires comprehensive consideration of factors such as sewage quality, water volume, microbial content and effluent requirements. The optimal amount should be explored through laboratory tests and practical experience to avoid waste and secondary pollution. There are two ways of dosing: gravity dosing and pressure dosing. Small plants are suitable for gravity dosing, while large and medium-sized plants are suitable for pressure dosing to ensure accuracy and stability. At the same time, it is necessary to ensure a contact time of about 30 minutes to allow sodium hypochlorite to fully react with microorganisms. The specific time is adjusted according to the actual water quality and disinfection requirements.
However, the application of sodium hypochlorite also faces challenges. The effective chlorine in its solution will gradually decay, affecting the disinfection effect, so the storage time should be shortened, stored away from light and at low temperature, and the content should be tested regularly to adjust the dosage in time. It is corrosive and irritating, and operators need to be equipped with protective equipment and strengthen ventilation in the operating room. If excessive dosing leads to excessive residual chlorine in the effluent, it will affect the ecology of the receiving water body. Therefore, it is necessary to strengthen the monitoring of residual chlorine in the effluent, and add reducing agents such as sodium sulfite for dechlorination when necessary.
Looking to the future, with the improvement of environmental protection requirements and the development of sewage treatment technology, sodium hypochlorite has broad application prospects. We will combine intelligent control technology, accurately control the addition, improve treatment efficiency and quality, and develop more environmentally friendly and efficient preparation and application technologies.
Bluewav will continue to pay attention to new sewage treatment technologies, provide customers with high-quality solutions, protect green waters and green mountains, and help the development of sewage treatment.