I D
× COMMENTARYCOVER STORYIN THE NEWSNEWSFRONTSCHEMENTATOR + Show More BUSINESS NEWSTECHNICAL & PRACTICALFEATURE REPORTFACTS AT YOUR FINGERTIPSTECHNOLOGY PROFILEEQUIPMENT & SERVICESFOCUSNEW PRODUCTS + Show More

Comment Sustainability

Commercial plant will recover salts from incinerator flyash

By Gerald Ondrey |

Ragn-Sells AB (Sollentuna, Sweden; www.ragnsells.com) has partnered Hitachi Zosen Inova AG (Zürich, Switzerland; www.hz-inova.com) for the construction of a new plant that is designed to extract resources from flyash — a toxic byproduct of waste incinerators that normally ends up in landfills. When the facility starts up by 2022, it will be able to process flyash corresponding to half of the yearly production in Sweden.

The plant is based on the Ash2Salt technology, a patented process developed by Ragn-Sells’ subsidiary EasyMining AB (Uppsala, Sweden; www.easymining.se). In the process, flyash is first washed, creating a leachate solution containing chloride salts and heavy metals. The leachate is filtered, and the detoxified residue — with much smaller volume than the original ash — safely landfilled, or used in construction materials. The heavy metals are removed from the leachate by precipitation with sulfide, and ammonia recovered as ammonium sulfate, leaving a solution of chloride salts. The salts are then separated using a single evaporator by a patented process, to produce commercial-grade KCl, NaCl and CaCl2. One ton of flyash can contain as much as 400 kg of salts.

Each year, Sweden produces roughly 300,000 metric tons of fly ash. Around half is sent to a discontinued limestone quarry on the Norwegian island of Langøya (near Oslo). This practice means that neither resources nor toxic substances are extracted. Additionally, the Langøya quarry will reach maximum capacity and close down within a few years.

The plant, which is now under construction at Ragn-Sells’ Högbytorp site in Bro (outside Stockholm), is one of the largest single investments ever within the Swedish material-recycling sector.

flyash

Related Content

Andritz

Minimizing particle breakage and mother liquor residue in technical salts production

Technical salts and crystallization products have found a broad spectrum of different applications in the industrial sector in the past decades. One of the most frequently used salts is sodium chloride...

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
The Big 6 level measurement technologies: Where to use them and why
Minimizing particle breakage and mother liquor residue in technical salts production
Expectations are shifting: How measurement solutions can help overcome chemical industry challenges
CoriolisMaster: The SmartSensor solution
ABB in Chemical Industry

View More