Patent ID: 9676633
Date: 2017-06-13
CPC Classifications: B01D,C01C,C05C

Claim:
1. A process for preparing a crystalline ammonium sulfate product, which process comprises: a) subjecting a feed solution of ammonium sulfate to crystallization in a crystallizer to form a first slurry of ammonium sulfate crystals; b) subjecting the first slurry of ammonium sulfate crystals to a first size classification to yield a first coarse ammonium sulfate crystal fraction and a first fine ammonium sulfate crystal fraction; c) recycling at least part of the first fine ammonium sulfate crystal fraction to the feed solution of ammonium sulfate; d) recovering a crystalline ammonium sulfate product from the first coarse ammonium sulfate crystal fraction, and e) subjecting a second slurry of ammonium sulfate crystals to a second size classification to yield a second coarse ammonium sulfate crystal fraction and a second fine ammonium sulfate crystal fraction, wherein (i) the second slurry of ammonium sulfate crystals is the first fine ammonium sulfate crystal fraction or (ii) the second slurry of ammonium sulfate crystals is withdrawn directly from the crystallizer.