3d model from bottom ash handling system.

Laitex offers solutions for bottom ash handling and sand recycling. Our well-planned solutions increase efficiency and production capabilities of the plant's operations.

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Bottom Ash Handling & Sand Recycling

Bottom ash is a coarse component of ash. Instead of going with the flue gases, it settles to the bottom of the boiler. Bottom ash handling refers to the process of removing and processing ash, slag, sand, and non-combustible particles from the bottom of a boiler to containers or a bunker. Applications can be utilized in different types of boilers.

As a result of the fuel combustion, some of the ash remains at the bottom of the boiler. The collection, cooling, recycling, and storage of bottom ash is an important part of the boiler’s operation. After bottom ash is collected on conveyors, it’s cooled with cooling screws or chain conveyors. Cooled ash mixture is conveyed to screening where sand and ash are separated. Sand is recycled back to the boiler while ash and oversized particles are directed to containers or bunkers.

In certain boiler types, bottom ash is removed from the boiler by a wet ash conveyor. With this ash removal method, non-combustible material is extinguished, and the wet ash is transferred to the bunker.

 

Conveying systems for bottom ash

Bottom ash handling and sand recycling systems are part of Laitex’s full scope solutions. We have delivered a variety of systems around the world, regardless of size, boiler type and fuel.

Hot ash requires robust equipment that is designed for extreme conditions. Laitex’s hardwearing cooling screws and chain conveyors cool ash down rapidly by several hundreds of degrees. Cooling equipment are always tailored according to customers’ needs and the cooling capacity is calculated using our own technology.

Usually, coarse material is separated from the fine material with Drum Screen or Vibrating Screen. In this process, the sand is also separated from the ash and can be recycled back to the boiler. For long and complex distances, pneumatic transportation is a cost-effective option. Ash is conveyed to storage using conveyors or pneumatic conveyor system. Especially when silos are located far from the boiler building, pneumatic conveyors are an excellent choice.

"Laitex is a flexible partner that takes our development ideas into account and reacts quickly even to small change requests. The project has progressed as planned, and we have reached all our milestones within schedule”

Jari Lahtinen, Project Manager at Turku Energia
Two rotary feeders used in a bottom ash handling.

Full scope solutions for bottom ash handling

In full scope solutions, the customer scope definition, engineering, automation, electrification, manufacturing, installation, commissioning including site related support, personnel training and after sales services are taken care of. Full scope delivery ensures that the system works seamlessly.

Our after-sales services include planned and preventive maintenance as well as supply of spare parts. Flow goes on with our expertise of various materials and process knowledge.