Water Softening Systems of Low and Medium Capacity

• Published in: Ecological Engineering & Environmental Technology Vol. 25; no. 12; pp. 194 - 202
• Main Authors: Radovenchyk, Iaroslav, Hordiienko, Kateryna, Radovenchyk, Vyacheslav, Overchenko, Тatiana, Ivanenko, Olena, Krysenko, Tamara, Sirenko, Lyudmila
• Format: Journal Article
• Language: English
• Published: Polish Society of Ecological Engineering (PTIE) 01-12-2024
• Subjects: calcium ions; domestic softening systems; filtration; flocculants; magnesium ions; water hardness; water softening; water treatment by phosphates
• ISSN: 2719-7050; 2719-7050
• DOI: 10.12912/27197050/194157

The current state of the hydrosphere is largely determined by human anthropogenic activities. Discharge of polluted waste waters into surface water bodies significantly worsens their quality and limits the possibility of safe consumption. One of the biggest sources of increasing surface waters mineralization and hardness is the discharge of spent regeneration solutions of natural waters ion-exchange softening processes, which creates a closed circulation cycle of sodium, calcium and magnesium chlorides. The necessity to reduce the intensity of this cycle and decrease environmental pollution is very actually today. The research of traditional soda-sodium softening technology has shown its low suitability for low and medium capacity systems due to necessity of water heating and subsequently pH adjusting. More acceptable solution was found in using phosphate anions as a precipitant, which ensures high efficiency in removing calcium and magnesium ions at a wide range of temperatures and pH levels. It was found that the solid phase formed during such treatment was difficult to separate from the liquid phase. Using of anionic flocculants was proposed as one of the solutions of this problem, which ensure high efficiency in separating the formed solid particles from water. Proposed technological scheme was designed for implementation as a pre-treatment stage in reverse osmosis systems of low and medium capacity.