In this study, membrane distillation pilot plant facility powered by district heating is considered for removal of drug residues from treated waste water and flue gas condensate treatment. The system consists of five pairs of air gap-MD modules. Three different cases were considered based on the configuration of the MD system in the district heating network. The test results showed that the MD process removes all except two from above thirty five drug residues tested, to below detection limits of the analytical method. The corresponding permeate rate, specific thermal energy consumption, and finally the membrane area required for an anticipated production capacity of 10m3/h were estimated and compared for the cases considered. Concentration tests were also done to get higher amounts of the compounds of interest, with up to 20 times concentrations. Treatment of flue gas condensates from a combined heat and power plant was also done to overcome problems (from previous study) of high permeate pH due to ammonia escape through membrane. Results showed that acidifying the feed sample made it possible to control ammonium slipping through the membrane in to permeate. Removal efficiency of other contaminants was also analysed.
QC 20150323