Inorganic fouling control in reverse osmosis wastewater reclamation by purging carbon dioxide

Shahid, Muhammad Kashif; Pyo, Minsu; Choi, Young-Gyun

Inorganic fouling control in reverse osmosis wastewater reclamation by purging carbon dioxide

2019

Shahid, Muhammad Kashif | Pyo, Minsu | Choi, Young-Gyun

Inorganic fouling on the membrane surface is one of the major prevalent issues affecting the performance and cost of reverse osmosis system. Chemical dosage is a widely adopted method for the inhibition of inorganic scale on the membrane surface. In this study, CO₂ was used to control inorganic scale formation on surface of reverse osmosis (RO) membrane in wastewater reclamation. The pH of influent could be lowered by purging CO₂. It caused an increase in solubility of inorganic salts in water resulting in discharge of principle ions in concentrate stream. A pilot plant study was conducted with four different RO modules including control, with dosage of antiscalant, with purging CO₂ and with co-addition of antiscalant and CO₂. The effectiveness of CO₂ purging was assessed on the basis of operational analysis, in-line analysis and morphological results. Ryznar stability index was used to determine the scaling potential of system. The examined data indicated that CO₂ purging was successful to inhibit scale formation on the membrane surface. Moreover, CO₂ was found more eco-friendly than antiscalant, as no by-products were generated in concentrate stream.

Показать больше [+]