Patent · US Active

Partially continuous countercurrent process for converting gypsum to ammonium sulfate and calcium carbonate

US9682868B2 · kind B2 · utility

3Cited by
5References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 25, 2016
Grant dateJun 20, 2017
Priority date
Expiry dateJan 25, 2036

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/80
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The present invention includes a partially continuous countercurrent process for converting gypsum, by reaction with ammonium carbonate, to products of ammonium sulfate and calcium carbonate by introducing the reactants into reactors, mixing the reactants for a predetermined amount of time, employing a novel combination of countercurrent flows coupled with the reactors operated in a batch manner with process recycle of liquids, removing materials from the reactor and separating solids from solutions wherein no reactants are added during the removal process and thus the reactants have sufficient time to react and ensure the desired degree of reaction, yield and purity of product calcium carbonate and ammonium sulfate while minimizing the reaction time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.