Intermittent pressurized operation of steam explosion pretreatment system.

An acid catalyzed steam explosion pretreatment system was developed to process wood chips for biomass conversion. The degree of mixing in the pressurizing process was found to be a crucial factor to saccharification efficiency. With a low load fill (100 l, half load) in the pressurized vessel, ribbon blender provided enough mixing power for wood chips. The temperature difference in the reactor was found to be less than 15 °C, the total saccharification efficiency can be up to 63%. At high load fill condition (200 l, full load), the temperature difference under regular mixing was found to be quite large (20 °C) with a low saccharification efficiency of 38%. To increase the temperature uniformity, an intermittent pressure pulsation method was used. The pressure pulses helped the vertical mixing and a total saccharification efficiency up to 65% can be reached in the improved pretreatment process. [ABSTRACT FROM AUTHOR]