Energy‐Efficient Size Reduction Technology for Wet Fibrous Biomass Treatment in Industrial Biofuel Technologies

Abstract

Biomass size reduction belongs to the high energy-consuming operations in industrial biofuel technologies. Its energy requirement actually ranges from hundreds to thousands of kilowatt-hours per ton of dry biomass. These high energy values are primarily caused by energy demand of disintegrators used for wet fibrous biomass. Therefore, the reduction of this energy requirement could significantly improve the whole process economics. Suitable disintegrators were searched and several potential industrial technologies of mechanical disintegration for wet fibrous biomass with respect to minimum energy demand were designed. Wet wheat straw served as model material to evaluate their energy requirements. The technology with the least energy demand was composed of a new, fully developed retting mill.

Energy‐Economic Analysis of Thermal‐Expansionary Pretreatment for Its Implementation at a Biogas Plant

“…Based on recommendations 9, 10, 12, the suspension entering (stream 1, 6) into the milling machine has 40 wt % TS . of water concentration to intensify the mechanical disintegration.…”

“…2, the wheat straw (stream 1) was mixed with preheated water (stream 3) and sent to the milling machine (C‐101) by the screw conveyor (J‐100). The mixing of preheated water and wheat straw was done for intensification of the milling in the milling machine 12. The suspension (stream 4) was sent to the homogenization vessel (M‐104) and mixed with recirculated water (stream 15).…”

“…2 and 3. The mass balance for milling was found 12, and the mass fractions and temperatures for thermal‐expansionary pretreatment were realized 9, 10. For the energy assessment only the main ideas were kept in mind to perform the calculations, namely, to have a temperature of 185 °C before the expansion vessel (F‐107) and to create mesophilic conditions in the digester (M‐113).…”

Biogas Plant Upgrade to CO2‐Free Technology: A Techno‐Economic Case Study

“…A biogas plant including substrate pretreatment technology was designed using our previous studies [11] and the studies of other authors [9,10,32,33]. The wheat straw is mixed with water and transported via the screw conveyor J-101 to the retting mill, at 60 and 40 wt %, respectively.…”

Mechanical Disintegration of Wheat Straw by Roller-Plate Grind System With Sharp-Edged Segments

“…To find the optimum particle size, it is important to know the relationships among particle size, energy demand and biogas yield. Knife, hammer, roll, colloid mills and combined extruder-colloid mill units are widely used for disintegrating lignocellulosic biomass [12]. Yu et al [13] studied the energy requirements of hammer mills.…”