Energy and environmental analysis of disposing of concentrate by injecting it back into the deep geological formation

摘要

Protection of the environment is one of our most important obligations. All types of water treatment processes can have some impact on the environment, but the degree or extent of this impact depends on the technology used. The assessment of the feasibility of implementing the water desalination process on an industrial scale is largely dependent on the method and possibility of disposing or utilizing the concentrate. Concentrate is generated as a by-product of the separation of the minerals from the source water used for desalination. The characteristics of the waste stream depend on the quality of the feed water, the quality of the produced water (depends on various recovery levels), the pre-treatment method (added chemicals) and cleaning procedures used. In sea water desalination, the concentrate is usually discharged back into the sea. More difficulty should be expected when such systems are operated inland. The concentration of minerals and contaminants in brines or concentrate is usually approximately double that in feed water or higher. Therefore, the manner in which the concentrate is disposed of will largely determine the cost of desalinating water in an inland setting. Due to environmental considerations, injecting the concentrate back into the deep geological formation could be the preferable solution. This paper presents an energy and environmental analysis in disposing concentrate from the membrane process in inland water systems.