Integration of membrane distillation into heat paths of industrial processes

Economic analysis of desalination technologies in the context of carbon pricing, and opportunities for membrane distillation

“…This however means heat recycling is not possible. A recent trial of MD on a sea water cooled power station's waste heat from our group [52] demonstrated that electrical efficiency can be 1 [28,53]. Assuming this electrical demand is in practice 1 kWh/m 3 , under a carbon tax and reference plant scale, we see cost drop to $0.45/m 3 .…”

“…Research intensity picked up in the 1980's [5] due to rising water, energy and environmental issues. We have previously explored polymer and ceramic membranes for desalination, and explored MD in dairy processing and industrial process integration [24][25][26][27][28]. While MD researchers have already focussed on relative technology costs, process optimisation, module design and fouling, this paper presents results on a niche operation of extended RO recovery, as well as the relative price of MD under a carbon tax and in a modified operational mode.…”

“…Despite efforts to improve process efficiencies, there are viable sources of such heat, for example the abundant waste heat exhausted from a power station at 40 °C, which has no other value internally, but valuable as a source of energy for MD. With increased process integration, it is possible to explore options on utilising the existing heat paths in processes to become the heat source and sink to treat a separate process stream by MD [28]. Therefore the constraint to find 'waste' heat sources is lifted, but the compromise is increased process complexity.…”

Advances in Membrane Distillation for Water Desalination and Purification Applications

“…Despite promising improved single pass recovery that reduces the electrical energy requirement proposed in Equation (13), condensing/boiling vapor within a module is practically difficult and no experimental validation was presented. Instead, the MDHX concept is more practical, and the concept was validated with experimental data [155,156]. Figure 17.…”

“…As shown in Figure 17, the MD heat exchanger (MDHX) proposes a MD concept where the heat is coupled directly into the MD module by directing separate process streams into the MD module to both supply and remove heat from the MD channels [155,156]. The benefits include conveniently merging MD and process heat exchange into a single unit, but also it allows for direct heat conduction where it is lost.…”