Reuse, treatment, and discharge of the concentrate of pressure-driven membrane processes.
Application of pressure-driven membrane processes (microfiltration, ultrafiltration, nanofiltration, and reverse osmosis) results in the generation of a large concentrated waste stream, the concentrate fraction, as a byproduct of the purification process. Treatment of the concentrate is a major hurdle for the implementation of pressure-driven membrane processes since the concentrate is usually unusable and has to be discharged or further treated. This paper reviews possibilities to treat or discharge the concentrate: (i) reuse, (ii) removal of contaminants, (iii) incineration, (iv) direct or indirect discharge in surface water, (v) direct or indirect discharge in groundwater, and (vi) discharge on a landfill. General guidelines are given for the choice of a proper method as a function of the origin and composition of the water treated. Next, the further treatment of the concentrates in four application areas of pressure-driven membrane processes (drinking water industry, leather industry, and membrane treatment of landfill leachates and of textile process waters) is discussed.
Van der Bruggen
Bart
B
Laboratory for Environmental Technology, Department of Chemical Engineering, University of Leuven, W. de Croylaan 46, B-3001 Heverlee, Belgium. bart.vanderbruggen@cit.kuleuven.ac.be
Lejon
Liesbeth
L
Vandecasteele
Carlo
C
D003247:Conservation of Natural Resources; D004787:Environmental Pollution / Q000517:prevention & control; D005374:Filtration; D017408:Guidelines as Topic; D007220:Industrial Waste; D008567:Membranes, Artificial; D036103:Nanotechnology; D009995:Osmosis; D011312:Pressure; D012037:Refuse Disposal / Q000379:methods; D018508:Water Purification / Q000379:methods*
D007220:Industrial Waste; D008567:Membranes, Artificial