An Overview of Demineralization Water Treatment Plants
The term demineralization is typically reserved specifically for ion exchange processes. Usually natural occurring water contains many dissolved solids in dilute forms which are usually various types of salts. These solids are known as TDS. Demineralization, also known as deionization, is a process which removes minerals salts from water through the ion exchange procedure. Both cation and anion are removed through this process which is also known as deionization. In other words, it is a wastewater treatment process.
GRAM integrates good design procedures for optimum results from demineralization. With mixed bed (MB) ion exchanger, high purity water can be produced for high- pressure boiler applications. There are two types of deionization or demineralization processes:
- Mixed-Bed Demineralization
- Two-Bed Demineralization
Two-Bed Demineralization : This is a process with two vessels – one with a cation resin and the other with anion resin. First, water passes through a cation exchanger. Every cation gets exchanged with equivalent hydrogen ions. This keeps the water electrically balanced. Water leaving the cation then passes through an anion exchange. The same principle is applied here and anions are exchanged with hydroxylions.
Mixed-Bed Demineralization : Here, instead of two different vessels, the cation and anion resins are mixed in a single pressure vessel. This process is definitely considered to be more efficient than the two- bed plants but the regeneration process involved here is more complicated. The mixed- bed plants result in higher quality water than the two-bed plants. However, they are normally used when higher level of purification is required. After the two-bed demineralization treatment, water is further polished by the mixed-bed process.