In this work, the integration of two MD configurations was investigated as a possible mean to reduce the specific energy consumption. In particular, tests of Direct Contact Membrane Distillation (DCMD) and Air Gap Membrane Distillation (AGMD) were carried out on lab-scale modules of 40 cm2. In both cases, a commercial flat polypropylene membrane (Membrana, Germany) of 0.2 ?m was used, and the experiments were carried out by sending distilled water as feed at different temperatures (40°C-50°C-60°C). For the DCMD configuration, different feed flow rates (30 L/h-50 L/h-100 L/h) were also investigated, whereas the operative feed flow rate for the AGMD module was fixed at 100 L/h. Based on the achieved results on single modules, integrated schemes with the feed exiting from the DCMD module sent as coolant stream in the AGMD module -where it is heated by the permeating vapor, before being recycled back to the DCMD module- were analyzed. The integrated DCMD-AGMD systems where finally compared, in terms of specific energy consumption, Gained Output Ratio (GOR) and permeate production, to the single DCMD units.
Improvement of the membrane distillation performance through the integration of different configurations
Alessandra Criscuoli
2015
Abstract
In this work, the integration of two MD configurations was investigated as a possible mean to reduce the specific energy consumption. In particular, tests of Direct Contact Membrane Distillation (DCMD) and Air Gap Membrane Distillation (AGMD) were carried out on lab-scale modules of 40 cm2. In both cases, a commercial flat polypropylene membrane (Membrana, Germany) of 0.2 ?m was used, and the experiments were carried out by sending distilled water as feed at different temperatures (40°C-50°C-60°C). For the DCMD configuration, different feed flow rates (30 L/h-50 L/h-100 L/h) were also investigated, whereas the operative feed flow rate for the AGMD module was fixed at 100 L/h. Based on the achieved results on single modules, integrated schemes with the feed exiting from the DCMD module sent as coolant stream in the AGMD module -where it is heated by the permeating vapor, before being recycled back to the DCMD module- were analyzed. The integrated DCMD-AGMD systems where finally compared, in terms of specific energy consumption, Gained Output Ratio (GOR) and permeate production, to the single DCMD units.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.