Hybrid desalting technology maximizes recovery

Reuse, Treatment, and Discharge of the Concentrate of Pressure-Driven Membrane Processes

“…A more general method is the further treatment of the concentrate by distillation techniques such as multi-stage flash evaporation (MSF) and multi-effect distillation (MED). The combination of RO with these techniques may have a synergetic effect: the RO feedwater can be preheated by using it as a cooling water for the distillation, which increases the RO performance; furthermore, freshwater recovery is higher, and the remaining brine can be used for salt production ( , ). The combination of RO and distillation is an important evolution, and optimization of this hybrid process (by, for example, replacing the first RO unit in a two-step process by a NF unit) might lead to a significant improvement of the desalination process.…”

“…For the production of drinking water from surface water or groundwater, MF and UF are the most commonly used membrane processes, although the number of NF applications is also increasing. The use of MF and UF on a large scale only started in the beginning of the 1990s, so that the (29,36,37,50) as fertilizer, for soil improvement, as fuel production of salts and other minerals further treatment concentration by water removal: (32,34,47,48,(64)(65)(66)(67) thermal (e.g., evaporation, distillation) other (e.g., electrodialysis, settling) removal of specific compounds: activated sludge: organic compounds oxidation processes: (electro)chemical, photooxidation adsorption/ion exchange incineration rotating kiln furnace (hazardous waste) grate furnace (nonhazardous waste) discharge in surface water direct discharge (40)(41)(42) indirect discharge via sewage system discharge in groundwater application on the land: irrigation, evaporation ponds (33,44) deep injection in the soil landfilling as solid waste after pretreatment (57,58) with additional treatment (e.g., tabilization/solidification) without additional treatment as liquid waste VOL. 37, NO.…”