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Study on thick cell EDI process for ultra pure water production

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Abstract

The ultra pure water production using a self-designed thick cell EDI stack is investigated by using one stage reverse osmosis permeates as feed solutions. The results show that the operating conditions including applied voltage, dilute flowrate, concentrate flowrate and feed conductivity significantly influence the resistivity of the EDI product. Under conditions of dilute flowrate of 36 L/h, concentrate flowrate of 3.8 L/h, and applied voltage of 36 V, a product stream with resistivity of 16-18 M · cm is achieved.

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... The effects of operating parameters on EDI performance are shown in Table 1. The main technological parameters determining the performance of EDI technique are the current strength and voltage, flow velocity in the diluate and concentrate compartment, temperature and ions concentration (inside both feed and product water), pressure, and the degree of conversion (Fedorenko 2003, Li et al. 2009, Salem 2000. The amount of ions transported through ion exchange membrane is directly proportional to current density (Ervan andWenten 2002, Kurup et al. 2009) and temperature (Song et al. 2005). ...
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