Brackish water desalination for agriculture: Assessing the performance of inorganic fertilizer draw solutions

Abstract

Brackish water desalination for agriculture: assessing the performance of inorganic fertilizer draw solutions.

Unlocking the application potential of forward osmosis through integrated/hybrid process

“…As the product of a simple FO system is not pure water, but rather the water is trapped in the diluted draw solution, to obtain a pure water product FO needs to be part of an integrated process with a second step aimed at both re-concentrating the draw solution and producing a pure water product. The exception to this is in applications where the primary product is a concentrated feed and/or where the draw solute has been chosen where reconcentration is not required, such as seawater [93], fertiliser solutions which can be added to irrigation water [94][95][96][97][98], or lignosulfonate which can be applied to crop soils as a conditioner [99]. The majority of draw solution regeneration systems which have been investigated in the laboratory can be broadly divided into the categories of: pressure-driven filtration; thermally driven systems; magnetic recovery; electrolytic recovery; and precipitation based systems.…”

An integrated fertilizer driven forward osmosis- renewables powered membrane distillation system for brackish water desalination: A combined experimental and theoretical approach

“…In all FO filtration tests, deionized water (DI water) and synthetic brackish water solutions were utilized as feed solutions. The composition of the synthetic brackish water was described in our earlier work [10]. The synthetic brackish water was prepared with different total dissolved salts (TDSs) ranged from 10, 000 mg/L to 20,000 mg/L by adding NaCl, Magnesium Chloride (MgCl2), Na2SO4, potassium chloride (KCl), and calcium chloride (CaCl2) to DI water.…”

“…The bench scale FO system set-up was given in our previous work [10]. In brief, the system consists of a flat custom-made cell with dimensions of 16.6 cm × 8.6 cm, a total active area of membrane around 8.4 cm 2 , two reservoirs for the draw and feed solutions, and a data recording system.…”

“…The later caused a reduction in the effective osmotic pressure and addition of more contaminants into the feed solution. When fertilizer draw solution was used for the FO system, the interaction of this draw solution with the membrane material may alter the structure of the membrane [9,10]. Also, the final draw solution should be further diluted by potable water to obtain the required concentration for irrigation water.…”

“…More importantly, FO should be accompanied by a recovery system to regenerate the draw solution and extract potable water from the diluted draw solution. Essentially, the production of drinking water can be performed by a second recovery system such as RO [10], ultrafiltration (UF) [11], nanofiltration (NF) [12], membrane distillation (MD) or thermal processes [7]. However, these methods require high energy harvesting and capital cost to regenerate the diluted draw solution.…”