During its manufacturing processes, Mondi Merebank produces by-products such as bark, sawdust, residual fibre and ash. With over 170 250 tonnes of this material transported to landfill sites annually, Mondi recognised the potential of utilising this as renewable energy feedstock. Babcock partnered with Mondi to formulate a solution to satisfy national and local emission requirements and reduce the levels of nitrogen oxide (NOx) and sulphur oxide (SOx). The resultant Atmospheric Fluidised Bed Combustion (AFBC) boiler design contains several innovations. The design incorporates combustion of coal as an auxiliary fuel or, alternately, Sasol gas fed via an in-bed gas firing system designed by Babcock.
Interesting fact:
The Mondi Merebank boiler is the only AFBC boiler in the world to burn six fuels of different qualities simultaneously in various ratios.