Biomass gasification for combined heat and power in the cane sugar industry.

Sugar manufacturing requires energy for motive power and thermal processing. Electric power generation for export is also an important co-product in some locales. Biomass gasification technology coupled to a combustion turbine topping cycle and a steam generator/turbine bottoming cycle has the potential to increase electricity generation efficiency when integrated with a sugar factory. This paper reviews gasification fundamentals and the status of efforts to commercialize the technology. Case study results of a pressurized (20 bar), bubbling fluid-bed gasifier, combined cycle system integrated with a 2800 tonne cane per day sugar factory are presented. Using this system, the roughly 400 tonnes of fiber generated' per day could be utilized to generate 22 MW e for export, an efficiency of 22%. With the sugar factory's present configuration, the process requires a supplemental boiler fired on fuel oil to generate adequate low pressure steam to satisfy thermal demand. Improving energy management to reduce steam consumption to 36% on cane would alleviate the need for the supplemental boiler. Other options for improving steam production in the energy conversion system are also identified.