Magaldi solution for

The MAR® Magaldi Ash Recycling is an improvement of the MAC® system for “dry” extraction, cooling and handling of bottom ash from solid fuel fired boilers. That innovative process to recycle both “dry” bottom ash and economizer (ECO) ash in the combustion chamber aims at turning them into fly ash.

After the MAC® system, dry bottom ash along with ECO ash can be diverted to the MAR® system and then injected in the boiler through the coal pulverizers.

Dry bottom ash, extracted and cooled by the MAC® system, and ash from ECO hoppers are pneumatically conveyed and stored in small reception bins, located at the coal bunkers level. The finest particles, along with conveying air, are directly drafted into the combustion chamber or the flue gas ducts. Ash is extracted from the reception bins by tubular vibro-feeders and dosed to the coal mill feeding hoppers. Then ash is milled by coal pulverizers along with coal before being injected in the boiler through coal burners.

The MAR® system ensures the valorization both of bottom ash and ECO ash, turning a waste into a coal combustion product (CCP). Using CCPs, in cement or concrete production rather than disposing of them, conserves natural resources and reduces greenhouse gas emissions.

MAR® Advantages

• Conversion of all bottom ash into saleable fly ash.
• Complete elimination of costs associated with bottom ash disposal.
• LOI (loss-on-ignition) content reduction in fly ash due to dilution effect.
• Fly ash in compliance with international standards. In EU these are EN 197-1:2000/A3:2007 for cement and EN 450-1:2005/A1:2007 for concrete (LOI = 5% and fineness = 40% by mass as oversized particles on a 0.045 mm mesh sieve when wet sieved).
• Environmental benefits occur from mixing fly ash with cement, thereby reducing the production of cement and leading to a decrease in CO2 emissions that would have been produced without using fly ash as a “type II addition” (approximate reduction of 0.9 tons of CO2 for each ton of fly ash used).