Magaldi Group - Hot Bulk Material Handling and Dry Bottom Ash Extraction Systems

Magaldi Group, founded in 1929 in Salerno, is a leading manufacturer of industrial systems and plants for bulk material handling at high temperatures in coal-fired power plants, cement industries, steel plants, foundries and metal refining plants. In recent years, Magaldi has also been producing large plants for generating electricity from solar photovoltaics. Magaldi Group's mission is to design, manufacture and market reliable, high-quality systems that provide environmentally sustainable industrial solutions worldwide.

Hot bulk material handling and dry bottom ash extraction systems

The Magaldi Ash Cooler (MAC®) is a patented system for dry extraction, air cooling and mechanical handling of bottom ash from pulverised coal-fired boilers. With hundreds of installations worldwide since the 1980s, the MAC is the world’s leading dry bottom ash handling system for utility and industrial boilers of any size, burning any kind of fuel.

The main advantages of the MAC can be summarised in five points:

• Elimination of water usage in cooling and conveying bottom ash
• Reduction of carbon content in bottom ash
• Recovery of energy from ash and refund to the boiler
• Potential sale of dry, low carbon ash
• Reduction of operational and maintenance costs compared to conventional wet systems

Patented system for handling bottom ash

In order to reduce the environmental impacts of bottom ash dumping and make coal ash usable in cements or concretes, Magaldi has patented and developed a system able to extract, cool and recycle in the combustion chamber the ash produced by solid fuel-fired boilers.

The new Magaldi ash recycling (MAR) system combines the benefits of the MAC system with the following additional features:

• Conversion of bottom ash into saleable fly ash
• Elimination of costs associated with bottom ash disposal
• Reduction of loss on ignition (LOI) content in fly ash due to dilution effect of recycled bottom ash
• Production of fly ash in compliance with international standards; in the 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 0.045mm mesh sieve when wet sieved)
• Environment protection: decrease of CO2 emissions when mixing fly ash with cement in the concrete production

Fully automatic conveying system for mill rejects

The Magaldi Mill Rejects System (MRS) is a patented fully automatic steel-belt conveying system, designed to dry handle mill rejects from coal mills to storage silos. The system uses the reliable, high-performance Magaldi Superbelt®.

As no water is required in MRS operations, any environmental problems associated with wet systems are avoided, as are plugging problems which may occur either in sluice or pneumatic conveying systems.

Systems for high ash content coal applications

The SuperMAC system is a patented technology for bottom ash handling developed by Magaldi for high ash content coal applications. In these cases, traditional wet systems require a large amount of water for cooling bottom ash and, at the same time, can lead to boiler inefficiency.

The patented FLUIMAC system is an innovative system for the dry handling of bed ash from fluidised bed combustion (FBC) boilers. The FLUIMAC system is characterised by low operation and maintenance requirements and no water usage during ash processing. Using heat recovery from the ash, the FLUIMAC system is also able to increase boiler efficiency.

Reliable conveying systems for ash removal

The Ecobelt is a mechanical conveying system based on proven Superbelt technology. It was designed for economiser and fly ashes and is installed under the ash hoppers at flue gas side ducts, such as the economiser, de-NOx, air heater (AH) and electrostatic precipitator (ESP) / bag house filter. Problems from bridging or plugging in the eco-hoppers are eliminated, while operation and maintenance costs are kept low thanks, in part, to the absence of water.

The Magaldi Ecobelt is the ideal conveyor for handling hot materials, aggressive chemicals, heavy or sharp products. The Magaldi Ecobelt key component is the Superbelt, designed completely enclosed in a steel casing that prevents dust dispersion into the environment. A simple mechanical self-cleaning device removes the fine residuals from the bottom of the casing. The Magaldi O-chain is a chain conveyor enclosed in an independent casing that is tailored around the Magaldi Ecobelt tail section. Its function is to receive the fine residuals, taken from the Ecobelt bottom by the self-cleaning device, and to reload them onto the Magaldi Superbelt.

Dependable handling of bulk materials is essential to ensure the highest productivity in many industries. It is difficult for traditional conveyors to withstand the combination of temperature, weight, and abrasion of diverse materials. The Magaldi Superbelt conveyor is the dependable and environmentally friendly solution for these problems.