Influence of extruder and feedstock variables on torque requirement during pretreatment of different types of biomass – A response surface analysis

Sugarcane and Woody Biomass Pretreatments for Ethanol Production

“…Extrusion compares well to pretreatment technologies that have as drawbacks the batch processing mode, low solids loading or the use of large amounts of water, as already mentioned. Extrusion allows temperature control and does not require washing and conditioning steps, as required with diluted acid, alkali or ionic liquid pretreatments and does not produce effluent; thus there is no effluent disposal cost, no solids loss and no significant safety issues [86]. In comparison to other mechanical pretreatments, the extrusion process is normally less energy intensive than the milling pretreatment options.…”

“…Significant improvements in sugar yield after enzymatic hydrolysis have been reported for biomass pretreatment based on extrusion; examples include corn stover [92], Miscanthus [99], big bluestem, prairie cord grass, switchgrass, Indian grass [78,[83][84][85][86][87]. Nevertheless, there are no reports for the use of extrusion for pretreatment of sugarcane bagasse and straw aimed at cellulosic ethanol production.…”

“…If extrusion is combined with chemical pretreatment, due to its effective ability of kneading and mixing, the process requires less chemical loadings and thus less residual effluents are formed; the combination of extrusion with chemical pretreatment can further reduce energy consumption as it is economically suitable for large-scale operation. Furthermore, extrusion does not produce fermentation inhibitors, such as furfural and hydroxyl methylfurfural; nevertheless, low concentrations of acetic acid have been reported [84][85][86][87]. However, the extrusion pretreatment of lignocellulosic biomass requires the use of additives to increase the flow ability inside the barrel and avoid the accumulation, burning and blocking of the die during the process.…”

“…These functions can be performed in the same process, depending on the size of the extruder and the screw design. Since the 1990s, there has been an increase in the number of studies that use extrusion for biomass processing, such as for the extraction of compounds [74][75][76], densification [73,77] and biomass pretreatment for enzymatic saccharification [78][79][80][81][82][83][84][85][86][87]. For lignocellulosic biomass pretreatment, extrusion processing can provide a unique continuous reactor working at higher throughput and solid levels.…”

Optimisation of Extrusion for Enhancing the Nutritive Value of Palm Kernel Cake Using Response Surface Methodology

“…Under these conditions, the effect of temperature was negligible. With a high moisture content, most of the heat from the heater might have been used for moisture removal from the PKC (Karunanithy and Muthukumarappan 2011). Also, under these conditions, the effect of extrusion on the polysaccharides was low because the shearing effect of the screw was the only factor that contributed to the breakdown of the polysaccharides.…”