United Conveyor Corporation (UCC) has released an innovative pin-paddle mixer/unloader designed specifically for conditioning high-calcium ash, with reduced build-up, maintenance time and expense. The mixer/unloader conditions ash and other abrasive material with water to suppress dust and ease transport to trucks and rail cars. Paddles push and propel material forward, while fast, counter-rotating shafts ad pins lift the material and create turbulent mixing to expose the ash for optimal wetting.
“Fly ash containing high amounts of calcium compounds from powder river basin coal and/or emission control processes can create a number of challenges for plants using traditional methods of ash conditioning for disposal,” states Dan Charhut, UCC vice president of technology. “Frequent wet/dry cycles (starts and stops) accelerate a cement-like build-up of material, which increases power consumption while decreasing throughput capacity. UCC incorporates new design features into its pin-paddle mixer/unloader to address these problems, resulting in less clean-out maintenance.”
The new design features include patent-pending cleaning chains, designed to generate contact against the ash material and pin-paddles to reduce build-up during each cycle stop. The cleaning chains can improve mixer/unloader throughput by up to 50%. They are offered as a retrofit kit or as an optional feature on new 4050 and 6050 mixer/unloaders.
New spray nozzle styles are utilized for improved water penetration into the bed of material for uniform conditioning and can be independently controlled to allow precise water discharge during start-up, mixing and shut down. Spray nozzles are located at the highest point of the mixer/unloader cover, minimizing the potential for plugging. Nozzles are accessible and can be replaced from outside the mixer/unloader.
Additional features of the pin-paddle mixer/unloaders include: the shafts and pins use covers made of ultra high molecular weight polyethylene (UHMW PE) material to resist build-up. Even distribution of power between shafts minimizes shaft stress and deflection. A toothed drive belt offers smooth, low-maintenance power transmission without the need for high-maintenance timing gears and lubrication.
Benefits of the United Conveyor Corporation pin-paddle mixer/unloader (model no. 4050 and 6050):
- Prevents high calcium material build-up
- Higher throughput capacity and performance
- Uniform conditioning of materials
- Low maintenance design
- Easy access
For more information about the UCC pin-paddle mixer/unloader, please contact UCC.