April 29-May 4, 2018
The process for manufacture of ammonium sulfate from gypsum, known as the Merseburg Process, named for the town in Germany where it was developed, has been commercially produced in plants in Austria, India, Pakistan and the United Kingdom in the past. It is based on reacting ammonia and carbon dioxide to produce ammonium carbonate, which is then reacted with gypsum to produce ammonium sulfate and calcium carbonate. Ammonium sulfate is mainly used as direct fertilizer or in producing compound fertilizers. The global ammonium sulfate market is projected to grow 4% annually through 2025, from $4.6 billion to $6.8 billion. As global efforts to utilize more of the phosphogypsum produced in the production of phosphate fertilizers grow, the prospect of re-examining the economic viability would be timely. In addition to the potential for economic gain, the ability to capture and store carbon dioxide that is inherent in the process could result in a concomitant environmental benefit. Another potential environmental benefit can occur in locations where offshore disposal is or can be practiced. Disposal of the calcium carbonate produced, rather than phosphogypsum, could have the potential to offset the growing problem of ocean acidification and its resulting impacts on marine organisms.
Gary Albarelli, "Revisiting the Merseburg Process: Economic Opportunity and Environmental Benefit?" in "Beneficiation of Phosphates VIII", Dr. Patrick Zhang, Florida Industrial and Phosphate Research Institute, USA Professor Jan Miller, University of Utah, USA Professor Laurindo Leal Filho, Vale Institute of Technology (ITV), Brazil Marius Porteus, Foskor-Mining Division, South Africa Professor Neil Snyders, Stellenbosch University, South Africa Mr. Ewan Wingate, WorleyParsons Services Pty Ltd., Australia Prof. Guven Akdogan, Stellenbosch University, South Africa Eds, ECI Symposium Series, (2018). https://dc.engconfintl.org/phosphates_viii/14