Membrane heating/cooling steps

Such a membrane can be used at high temperature and the sealing remains effective even after repeated heating/cooling steps as shown in Figure 33.15 that shows permeation flux in the absence of leakages. 

The layers were very thoroughly washed (seven times at 60-80°C) to remove all traces of sodium. In the case of multiple layer processing, the wet supported layer was again positioned at the bottom of the autoclave and the complete procedure was repeated. After the last hydrothermal treatment the multiple-step membrane was dried and the template molecules were removed by heating at 550°C for 16 h (heating rate 10°C/h, cooling rate 20°C/h). 

The HWS equipment includes a CIP skid with a heat exchanger to heat and circulate hot water through the membrane system loop. Sometimes a heat exchanger is added to aid in cooHng during the cool-down period. The HWS procedure recommended by membrane manufacturers involves separate steps ... 

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