The influence of screw configuration on the pretreatment performance of a continuous twin screw-driven reactor (CTSR)

[Display omitted] ► Continuous pretreatment of biomass performed with CTSR. ► Obtained the high cellulose content, xylose yield, and enzymatic digestibility. ► High selectivities of cellulose to XMG and xylose to glucose were obtained. ► Screw configuration is a major factor affecting the pretreatment performance. A combination of a continuous twin screw-driven reactor (CTSR) and a dilute acid pretreatment was used for the pretreatment of biomass with a high cellulose content and high monomeric xylose hydrolyzate. With the newly modified CTSR screw configuration (Config. 3), the influences of the screw rotational speed (30–60rpm), of the pretreatment conditions such as acid concentration (1–5%) and reaction temperature (160–175°C) at the operating condition of biomass feeding rate (1.0g/min) and acid feeding rate (13.4mL/min) on the pretreatment performance were investigated. The cellulose content in the pretreated rape straw was 67.1% at the following optimal conditions: barrel temperature of 165°C, acid concentration of 3.0% (w/v), and screw rotational speed of 30rpm. According to the three screw configurations, the glucose yields from enzymatic hydrolysis were 70.1%, 72.9%, and 78.7% for screw Configs. 1, 2, and 3, respectively.