Bottom ash - safe and efficient handling
Jun 26, 24
History
In December 2008, a devastating environmental disaster occurred in Kinston, Tennessee.
The dam of a reservoir, which for years absorbed ash from the local coal-fired power station, ruptured under the load. Millions of cubic metres of black sludge poured over the region like a tidal wave, destroying houses and turning once-thriving local rivers into dead zones for fish.
This shocking event drew attention to the dangers of storing ash with a high water content and sparked an urgent discussion about safety and environmental protection.
Initial situation
A Chilean company that operates several coal-fired power stations wanted to optimise its existing process for conveying and securing bottom ash. The transport process for conveying the ash to the storage silo was difficult and inefficient.
The bottom ash from the combustion chamber of the power station boiler falls into a water bath where it cools down to below 50 °C. The lumpy mass is then transported by a trough chain conveyor over an incline (dewatering) to a crusher to achieve a maximum particle size of 15 mm.
Normally, a good distribution of coarse and fine particles in the medium is required for conveying, but this was not achieved in this process.
The ash cooled in the water bath regularly stuck to the belt conveyor, which led to high maintenance costs and wear.
The test
The previous conveying option with a belt and manual conveying proved to be cumbersome and required a lot of maintenance. In a long-term test, the cooled medium was fed directly into the crusher via a hopper and then into a conventional trailer concrete pump with manual operation, from where it was transported to the storage silo.
The solution
As a solution provider, Putzmeister has developed an automated pumping system that is specially tailored to the customer’s existing requirements.
- Greater occupational safety and less manual effort thanks to the combination of KOS 1040 with an extension hopper and agitators.
- By reducing the water content, the bottom ash is secured better and the volume is reduced at the same time.
- More efficient transport process.
- Automation through remote control of the system via a control room.
- Reduced maintenance costs.
- Working conditions improved and cleanliness increased thanks to the closed system from the pump to the storage silo.
This solution was successfully implemented at three of the customer’s locations.
Machines / Equipment
- KOS 1040 S transfer tube piston pump incl. extension hopper and agitator
- HA 75 hydraulic power pack
- Control cabinet 75
- DN 125 delivery line, approx. 15 m horizontally, approx. 25 m vertically upwards
- (varies between the individual lines and set-up sites)
published by Putzmeister Industrial Technology