Covestro leads research project to recover salt from industrial wastewater

One of the world’s largest polymer companies, Covestro, aims to use treated salt and purified wastewater in electrolysis to produce chlorine. In line with this objective, the Leverkusen, Germany-based materials manufacturer is leading a group of academic and industry partners in a new research project to find new environmentally friendly ways to recover salt and water from industrial wastewater.

Substantial amounts of wastewater with very high salt concentrations are being produced in many industrial processes. This wastewater represents a serious pollutant if it finds its way into bodies of water, particularly rivers and lakes used for potable water treatment.

The company believes that action is required to develop new, environmentally friendly and economically viable processes for the treatment and use of such wastewater.

“A key objective of this project is to increase the salt content of the salt solutions as much as possible in an environmentally friendly manner during the treatment process,” said project coordinator Dr. Yuliya Schiesser, a process researcher at Covestro. This will be done in part using the waste heat from the adjacent production plants.

“Our ultimate goal is to develop a process that benefits not just the plastics industry but other industry segments as well,” said Schiesser.

Covestro is planning a demonstration plant for testing purposes at its Krefeld-Uerdingen site in Germany. In early 2016, the company brought a pilot plant on stream there that uses a recycling process developed in-house to purify salt-laden process wastewater so that it can be reused for the production of chlorine, a key raw material for the manufacture of polycarbonate and other plastics.

This technology is the basis for the new joint project “Re-Salt” (recycling of salt-laden industrial process water).

Other project participants are the German Water Center, Donau Carbon GmbH, the University of Duisburg-Essen University, Dechema-Forschungsinstitut, Envirochemie GmbH and TH Köln – University of Applied Sciences.

Re-Salt is scheduled to run for three years and is funded by the German Ministry for Education and Research (BMBF) as part of the WavE funding measure.