Simple Solutions for Ash Handling Systems

Cliff Moss, VP for Materials Handling at ProcessBarron, detailed challenges and simple solutions for ash handling systems in the September issue of Biomass Products and Technology.  His article “Biomass Ash Handling: Simplifying the Challenges” details common pitfalls and simple solutions that can improve reliability, reduce downtime and minimize maintenance costs.  Article excerpt:


Bottom Ash and Fly Ash Systems

Some mills have ash systems that collect bottom ash material with their fly ash collection system. Adding the bottom ash to the fly ash collection often requires a cumbersome system to take the bottom ash to the back side of the boiler where the fly ash system is located.  Adding these systems together as one system has proven to be very unreliable and difficult to maintain. The ash particle characteristics and properties of bottom ash and fly ash are very different and therefore have different conveying principles. Trying to incorporate both in one conveyor design creates too much cost, complexity, and tradeoffs in design reliability.


The problem these mills encounter with their ash system is that the bottom and siftings hopper material (ash, rocks, sand, clinker, and wood) does not work well in a fly ash system arrangement. When this material is mixed with the fly ash it requires the conveyors downstream to have a more complicated design such as dual strand drag chain conveyorverses single strand drag chain conveyor arrangement.  It also causes difficulties in the ash silo and conditioning system designs due to the solid bottom ash particles entrained with the fly ash particles.


The best way to avoid these problems is to treat the bottom and sifting hopper material as bottom ash, and handle it separately from the fly ash. Keeping these systems separate allows for a system that will operate very predictably and reliably for each of these two very different types of material/ash. Additionally, this will require the least amount of conveyors and minimize the total length of the required conveyors…


For more insight, download the full article in the ProcessBarron Knowledge Base.