Demineralization of Wastewater by Electrodialysis.

摘要

Demineralization of carbon-treated secondary effluent by a 45.5 1 pm (12gpm) Ionics electrodialysis pilot plant was investigated at the Pomona Advanced Wastewater Treatment Research Facility,Pomona,California. Slime formation (organic fouling) on the membranes and spacers of the electrodialysis stack during continuous operation significantly decreased the effectiveness of the electrodialysis process to demineralize municipal wastewater. If the total COD of the feedwater was maintained at or below 10mg/l, a weekly enzyme-detergent flush maintained the total dissolved solids (TDS) removal in the design range of 30-35percent. A cost estimate for a 10MGD single stage electrodialysis plant based on the operating results obtained at Pomona was made. The estimated cost of 19.4cents per 1,000gallons was based on the use of carbon-treated secondary effluent with an average TDS concentration of 540mg/l and a total COD of 10mg/l or less to produce a product water with 30-35percent reduction in TDS.