Using Reverse Osmosis, Electrodialysis, and Nanofiltration to Increase Affordable Desalinated Groundwater Use in Texas

Abstract

Droughts and flooding that have impacted Texas have decreased surface water availability, while draining the limited number of non-saline groundwater sources. Therefore, desalination of saline groundwater would be able to supplement the increasing demand of water for industrial and domestic uses. The process would have to be affordable and capable of meeting WHO1 standards for drinking water. Of the current desalination options available, the methods analyzed are reverse osmosis, electrodialysis, and nanofiltration. Of the three options, it was determined that reverse osmosis was the best solution for the desalination of saline groundwater for both industrial and domestic uses. Reverse osmosis filters saline water to meet WHO standards for sodium and chloride ions. Although both RO and electrodialysis processes were effective enough for eliminating total dissolved solids in the sample saline waters, only RO yielded potable water. If this system is successfully implemented, it could supplement the nonsaline groundwater being used for human consumption, as well as yield RO discharge water for residential or industrial uses. As a result, the severe impacts of the reoccurring droughts in Texas can be reduced, while lessening the drainage of the non-saline groundwater reservoirs in Texas. Keywords: Desalinated Groundwater, Reverse Osmosis, Electrodialysis, Nanofiltration, cost- comparison, potable water, brackish water desalination