Tarragona, Spain – Covestro is planning to build its own chlorine production plant in Tarragona, using a homegrown process, oxygen-depolarised cathode technology.
Covestro to use home-grown chlorine technology in Tarragona
The plant will consume around a quarter less energy than a conventional plant producing the same amount of chlorine.
Chlorine is a key raw material in the production of diisocyanates using the phosgene method.
Covestro said it is currently investing about EUR 200m at Tarragona to increase the site’s competitiveness, the new chlorine production plant being a key part of the investment.
Construction of the new plant is scheduled to begin in the first half of 2019.
'About one-third of the production costs are usually spent on energy. The selected technology makes an important economic contribution,' Covestro explained.
According to chief technology officer Klaus Schafer, the main reasons for choosing the process were sustainability and energy efficiency.
'This is a success story for us since the development of this technology began at our company over two decades ago,' added Schafer.
Covestro, and partners ThyssenKrupp Uhde Chlorine Engineers, developed the technology, which they claim consumes around 25% less energy than conventional electrolysis through the use of an oxygen-depolarised cathode (ODC).
ODC technology is based on the conventional membrane process with a crucial difference: the normal hydrogen-generating electrode is replaced by an oxygen-depolarised cathode.
'Only chlorine and caustic soda are produced. As a result, a voltage of just around two instead of three volts is required,' added the company.
'The change in this process sounds simple, but was a ground-breaking development ,' said Hanno Brummer, head of production at Covestro's polyurethanes segment, which includes the company’s global chlorine activities.
The process was invented in 1992, and development started soon after. The first industrial-scale demonstration plant was built in Krefeld-Uerdingen, Germany in 2011.
This story first appeared in Plastics News Europe.