Optimization of Gas Scrubbing in the Calcination of Struvite

Abstract

During the calcination of magnesium ammonium phosphate hexahydrate (struvite) in the process of recycling to obtain phosphoric acid, ammonia is released in addition to water and carbon dioxide. With a gas scrubber, e.g., in the form of a bubble column reactor, ammonia can be recovered as a usable valuable material. With water as an inexpensive and effective absorbent, almost complete absorption (92 %) of the ammonia from the exhaust air can be achieved.