The Acid Test: New Way to Recover Resources from Industrial Waste (Video)
The galvanizing business involves hot and arduous work, turning corroding steel into protected metal using baths of hydrochloric acid and molten zinc. It's also a business which EU researchers believe they can make cleaner and greener, with the latest membrane and dialysis technology.
The factory run by Sicilian firm Tecnozinco is one of their test grounds, where the goal is to find a new way to recondition and recycle the used acid from its plant. Steel is soaked in acid during galvanization, a process known as 'pickling'.
Right now, treating the 300 tonnes of spent acid the plant produces every year is a financial and environmental cost that adds up to significant overhead, as Technical Manager Alberto Di Cristofalo explains:
"We are in Sicily. And the problem for us is that the treatment plants for waste solutions are located in northern Italy. So there is a very high cost of disposal because of the distance. Moreover, these large quantities create a considerable environmental impact, both for the quantities of acid that we have to buy and for the quantities of waste that have to be disposed of."
The answer may well be a new machine built by the EU's ReWaCEM project consortium. Installed at the plant in spring this year, it can recycle 20 to 40 liters of used acid per hour, and extract the valuable metals dissolved within it.
The man behind the machine is Daniel Winter, from Fraunhofer ISEin Germany, and he explains how it works:
"These (acid) solutions are introduced into this innovative plant, which then extracts the various valuable components from the solutions, separates them into the acid, which can be re-used, which can be returned to the processes, and the salts, which can then be precipitated into a recyclable material, which can then be sold, and the wastewater no longer has to be disposed of, but is completely recycled."
Read the full story on EuroNews.
Video source: EuroNews on YouTube