Inter-pass caustic injection

Inter-pass caustic injection is commonly used to drive out carbon dioxide from the first-pass RO permeate/second-pass feed. Carbon dioxide, a gas that is not rejected by the membranes, is converted to bicarbonate alkalinity, which is rejected (see Chapter 3.2). Removal of carbon dioxide is particularly important for applications that polish the second-pass RO permeate with ion exchange. The conversion and, therefore, elimination of carbon dioxide from the permeate will reduce the loading on the anion resin. 

---

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

---