M69 Inland Desalination and Concentrate Management

Drivers, challenges, and emerging technologies for desalination of high-salinity brines: A critical review

“…The desalination of brackish water with 1,000-15,000 ppm TDS is a significant source of such concentrates, contributing ≈10,700 × 10 6 m 3 per year [24]. Not all inland desalination concentrates exceed 70,000 ppm TDS (our definition of hypersalinity) since desalination may be halted at low recovery yields, primarily due to membrane fouling constraints [59,60]. However, there is a growing push to operate brackish water desalination at higher recovery yields to lower the cost of concentrate disposal, which currently accounts for as much as one-third of total inland desalination expenditures [61][62][63]; as such, the volume of hypersaline concentrate is expected to increase in the coming years.…”

Desalination of brackish groundwater to improve water quality and water supply

“…To treat brackish groundwater, membrane desalination technologies, primarily RO and ED, are used without exception [7,8,9]. Thermal processes are not utilized, primarily because their energy requirements are independent of salinity, unlike membrane processes in which energy requirements decrease with salinity.…”

“…Scaling occurs due to the precipitation of inorganic salts, such as carbonate, sulfates, and silica, from the feedwater onto the membrane surface. Brackish water RO is especially prone to membrane scaling [7,9]. Biofouling arises from the growth of bacteria on the membranes, which depends on temperature, pH, dissolved oxygen and composition of feedwater.…”

“…These vary significantly with membrane type. Current brackish RO membranes remove between 98 and 99.2% of TDS from the feedwater and are designed to produce a permeate of approximately 500 mg/L [9]. They have a life expectancy of 2-5 years [7,9].…”

“…Current brackish RO membranes remove between 98 and 99.2% of TDS from the feedwater and are designed to produce a permeate of approximately 500 mg/L [9]. They have a life expectancy of 2-5 years [7,9]. Improvements in these membranes continue to simultaneously reduce desalination energy requirements and the rate of fouling.…”