Electrodialysis with heterogeneous ion-exchange membranes as competitive technology in ZLD applications

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F28676092%3A_____%2F22%3AN0000024" target="_blank" >RIV/28676092:_____/22:N0000024 - isvavai.cz</a>

Result on the web

<a href="https://sscheconference.sk/" target="_blank" >https://sscheconference.sk/</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Electrodialysis with heterogeneous ion-exchange membranes as competitive technology in ZLD applications

Original language description

Zero Liquid Discharge (ZLD) is an advanced water treatment process with the goal of reusing as much water as possible in the production process without the need to discharge any waste. ZLD process typically involves the following steps: pretreatment, concentration and thermal treatment. Concentration of dissolved solids in the ZLD system is usually accomplished by membrane technologies, such as reverse osmosis (RO), electrodialysis (ED) or by a combination of RO with ED. With the help of ED technology or the combination of RO + ED, recovery of more than 98 % of treated water can be achieved. Concentration of processed stream after ED should be as high as possible. Therefore, high electric currents need to be applied with high current efficiency and the module has to work at high ratio of concentrate to diluate conductivity. This way, the amount of waste stream entering ZLD thermal stage is significantly reduced. In industrial ED modules operated at high voltage, there is a risk of membrane stack burning due to shunt currents. RALEX® ED(R)-IF modules have a unique design of certain components ensuring that ion exchange membranes are electrically insulated from distribution system of liquids. Thanks to this, shunt currents are not able to pass from working chambers to distribution channels through membranes and to cause irreversible damage of membrane stack. At the same time, membranes themselves do not come to the surface of the membrane stack so the risk of short circuit currents is eliminated. This solution leads also to other improvements, e.g. maximum possible use of the installed membrane area or eliminated internal leakages, and makes ED(R)-IF module with heterogeneous membranes competitive compared to modules with homogeneous membranes which are in general more expensive but have better electrochemical properties. Whole R&D process from the idea to commercialized product is presented in this paper together with the comparison of ED performance of both new generation RALEX® ED(R)-IF module and the standard one.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20402 - Chemical process engineering

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů