Recycling salt from industrial wastewater
Covestro and partners from industry and academia are searching for new ways to recover salt and water from industrial wastewater as environmentally friendly as possible. The Leverkusen-based materials manufacturer is heading a research project with this as its objective. The aim is to use the treated salt and purified wastewater in electrolysis processes to produce chlorine
Many industrial processes produce substantial amounts of wastewater with very high salt concentrations. This wastewater represents a serious pollutant if it finds its way into bodies of water, particularly rivers and lakes used for potable water treatment. Action is therefore 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 (funding code: 02WAV1408).
With 2015 sales of EUR 12.1 billion, Covestro is among the world’s largest polymer companies. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative solutions for products used in many areas of daily life. The main segments served are the automotive, electrical and electronics, construction and the sports and leisure industries. Covestro, formerly Bayer MaterialScience, has 30 production sites around the globe and as of the end of 2015 employed approximately 15800 people (full-time equivalents).