Inland Brine Disposal for Brackish and Saline Water Desalination Plants Producing Drinking Water
Mentor:Ali Sharbat, Professor of Civil Engineering, California State Polytechnic University, Pomona
Since the implementation of desalination facilities, the by-product produced called brine (also known as concentrate or reject water), a solution of salt and liquid with an extremely high salinity content, has been a major problem worldwide. In coastal areas, ocean water discharge has been a convenient method for brine disposal yet for those desalination plants far from the coast, this method is no longer available. Conventional methods used today for inland brine disposal are: surface water and/or sewerage discharge, evaporation ponds, deep-well injection, and irrigation halophyte plants. The purpose of this project is to assist the decision makers in evaluating and choosing the best feasible option for concentrate disposal based on their unique circumstances. Implementation of the wrong disposal method may result in marine endangerment, soil salinization or groundwater contamination. The main criteria impacting the selection of a disposal method include: volume, regulations, quality of concentrate, public perception, geographical considerations, and capital/operational expenditures. Depending on the size of the desalination plant, the volume and rate of brine produced will vary and will affect in which method is chosen. Regulations are enforced for certain methods and make an impact on the overall cost. The levels of total dissolved solids (TDS), the total amount of minerals, salts or metals dissolved in a given volume of water in mg/L, will determine which disposal methods may be applicable. Public perception is essential for the sake of company image as well as maintaining a positive relationship with the community. Based on the demographic area, hydrogeological conditions and land availability must be considered. And most importantly, both capital and operational cost demands must be accounted for and met. The conceptual model will account for each of these criteria and formulate the most appropriate and efficient disposal method for all inland desalination plants in the U.S.