Operational experience of the brackish water reverse osmosis of the water treatment plant in Sant Joan Despí

Abstract

To ensure correct operation of any facility that uses membrane treatment technology (ultrafiltration, reverse osmosis, etc.) requires a set of maintenance and cleaning operations, which allow correct operation and optimum duration of membranes, and also ensure the quality of water produced. In 2009, the existing drinking water treatment plant in Sant Joan Despí started operating a treatment combining ultrafiltration and reverse osmosis technologies to ensure compliance with the health limits set by the Spanish Royal Decree RD140/2003. Specific antiscalant was developed especially for controlling calcium carbonate, calcium phosphate, and barium sulfate scales, which are the most problematic insoluble species in the brine of the reverse osmosis at the water treatment plant in Sant Joan Despí. Specific software was developed to calculate the optimum dose of antiscalant based on the feedwater chemistry, the temperature, and the RO plant’s conversion, thus minimizing operating costs. Furthermore, Adiconline RO was installed to measure online and in real time the concentration of antiscalant in the feed. This system analyzes the active ingredients of the antiscalant and allows controlling the dosage level of antiscalant at the required level. The operational data of the RO and the results of autopsy of different elements confirmed that actions taken had been appropriate to provide efficient operation.

Keywords:

• Reverse osmosis
• Ultrafiltration
• Brackish water
• Scale inhibition
• Antiscalant monitor

Notes

Presented at the International Conference on Desalination for the Environment, Clean Water and Energy, European Desalination Society, 23–26 April 2012, Barcelona, Spain