Well, if that's not an ace up your sleeve for the next round of hangmen! ELECTROCHEMICAL DEIONIZATION is also known as electrodeionization, describes a water treatment process and should definitely be abbreviated as EDI below for better readability. Let's slowly get to grips with this monstrous word: deionization or deionization means desalination. It is therefore a desalination process which takes place under electrochemical conditions, i.e. in which an electric field is used. Now imagine the following: An EDI module consists of several chambers. The water is fed in into the middle chamber, membranes are located to the left and right of it, and in the chambers behind the membranes, an anode is attached on one side and a cathode on the other. As a result of the resulting electric field, the negatively charged anions will migrate to the anode (positive pole), the positively charged cations to the cathode (negative pole). Due to the lack of ions, a dilute solution will be produced in the middle chamber, and a concentrated solution will be produced in the outer chambers at the poles. In addition, the electrical voltage causes the water to split into hydrogen and hydroxide ions, which always regenerate the ion exchange resin, which is located in the individual chambers, i.e. displace the salts from the resins. In summary, EDI combines the advantages of continuous desalination and ion exchange technology. It is often used for further deionization after reverse osmosis; in addition, it can also be used to desalinate seawater at low cost and purify it into drinking water.