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An innovative and sustainable process for reducing the environmental impact of stainless steel production, enabling impressive recovery rates and cost savings.

Periodic Reporting for period 2 - REGMAX (An innovative and sustainable process for reducing the environmental impact of stainless steel production, enabling impressive recovery rates and cost savings.)

Periodo di rendicontazione: 2019-06-01 al 2020-05-31

Pickling of stainless steel causes environmental problems for our ecosystem and generates high operational costs for stainless steel producers. In stainless steel pickling, parts of the acids are reacting with the steel surface and are transformed to chromium, nickel and iron salts. Globally more than 350,000 liters of mixtures of these acids are being used for stainless steel pickling processes every hour and turned in large amounts of waste acid. Disposal of spent acid causes significant environmental problems and endangers today’s stainless steel pickling operational licenses.
Before the waste acid can be discharged into the environment, it is typically diluted with water and neutralized with Ca(OH)2 forming calcium fluorides and calcium nitrates as well as metal hydroxides. The fluorides and the hydroxides precipitate and can be separated through a filtration process. As a result, toxic sludge and nitrate-containing wastewater is generated. The sludge needs to be transported to a landfill for hazardous waste. Depending on the environmental limits, the nitrate-containing wastewater needs to be processed further in a wastewater treatment plant or can be directly disposed into the environment.
With the REGMAX® technology, this is no longer an issue. For the first time ever, it is possible to transform all waste acid components into valuable resources - creating a closed loop of resources. By implementing REGMAX® technology, it is not only making the world a better one, but also reducing pickling costs. Neither sludge nor wastewater is generated and no DeNOx unit is needed. Recovery rates are >99% for HF and >98% for HNO3.
Sustec has completed the scale-up engineering and successfully installed, commissioned and tested the REGMAX® plant. The REGMAX® plant built next to one of the customers pickling lines turns the entire waste acid produced by this pickling line into fresh resources creating a closed loop of the materials. REGMAX® prevents harmful damage to the local ecosystems by not disposing of waste acids nor contaminated wastewater. The stainless-steel manufacturer’s consumption or disposal of the acids is eliminated, reducing the environmental impact of pickling. Generated metal oxides will be reused for the production of stainless steel and the valuable metals are reused instead of being landfilled. The process also improves the energy efficiency of plants and reduces greenhouse gas emissions, thereby mitigating the effects of climate change.
Sustec completed the erection of the pilot plant and performed the large scale demonstration. The project successfully validated the acid regeneration performance of the system.
This project has enabled Sustec to advance towards their mission to eliminate waste acids from the stainless steel industry. This project marks a major stepping stone in the development of the company, and for the development of the stainless steel market as a whole.
stainless steel coil pickling