• Transactions of the KSME C: Technology and Education
• /
• v.1 no.1
• /
• pp.83-90
• /
• 2013

The purpose of this study is to replace existing liquid chlorine with localization of on-site high (12%) sodium hypochlorite generation system. On-site high (12%) sodium hypochlorite generation system is higher the current efficiency of 38.7%, 54.6% reduction of salt consumption, and 97.3% lower rate of chlorate than on-site low (0.8%) sodium hypochlorite generation system.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.41 no.3
• /
• pp.183-189
• /
• 2017

Sodium hypochlorite used in water disinfection processes is generally in the production of chlorine to 0.8％. As the dose of chlorine increases, disinfection by-products (Chlorate) also increase simultaneously and exceed water quality standards. In this study, the electrolytic cell of a sodium hypochlorite generator (12％ chlorine) was adjusted to control the production of the disinfection by-products. As a result, it was possible to reduce Chlorate concentrations by more than 95％ by adjusting the pH of the electrolytic cell from 1.53 to 4.2 (normal pH of the electrolytic cell). As a low current is required to obtain these results, a 15％ improvement in the efficiency of the positive electrode is also observed. For the development of High Sodium Hypochlorite Generation can be used in a safe sodium hypochlorite solution, which is expected to contribute to improvement in the safety of the disinfection process.

• The KSFM Journal of Fluid Machinery
• /
• v.20 no.2
• /
• pp.69-74
• /
• 2017

Sodium hypochlorite, used as water disinfectant, is generated by electrolysis of salt. Compared to chlorine gas disinfection, it is free from high-pressure gas regulation and does not generate toxic gas, so it is increasingly used as a safe disinfectant. Despite these advantages, the concentration of sodium hypochlorite decreases with temperature during long-term storage, and the amount of chlorate increases when a large amount is added, it has mainly been applied to small-scale waterworks. To solve this problem, high sodium hypochlorite generation was developed. In this study, the changes of concentration and chlorate of sodium hypochlorite with time has been studied. As a result of the test, it was found that the usable period of sodium hypochlorite produced at a certain temperature or less was increased from 1.5 days to 13 days. Overall, sodium hypochlorite can be applied even in large-scale waterworks, which makes operation more stable and also reduces the disinfection byproducts, thus it contributed greatly to securing water quality.