Distilled spirits Lees are one kind of special biomass resources with high contents of cellulose, water and N element. Usually, they are generated in the production of distilled spirits by solid-state fermentation process and are difficult to burn completely.Researchers from Institute of Process Engineering, Chinese Academy of Sciences (IPE-CAS) proposed a new system-circulating fluidized bed decoupling combustion (CFBDC) to increase the burn efficiency of distilled spirits Lees The pyrolysis behavior of distilled spirits Lees in a fluidized bed reactor was studied as well to get optimized condition of the process.

CFBDC was a dual bed system developed by IPE previously including a fluidized bed pyrolysis reactor and a riser combustor. Using the system researchers got a high burn efficiency of distilled spirits lees and low-NOx emission. The results of the characterization of pyrolysis behavior of the raw distilled spirits lees showed that the tar yield reached its maximum when the temperature was in the range of 350-400oC. There were more CO and H2 and less CO2 in the pyrolysis gas as temperature increased. Most functional groups in char were found at low-temperature and disappeared at high-temperature. Based on the results, they found the optimized condition for pyrolysis process for CFBDC was better at intermediate temperatures between 300-600oC.

The work was supported by National Key Technology R&D Program (2009BAC64B05 and 2010BAC66B01). More results of the research have been published on Fuel Processing Technology.