Biological Pretreatment by Solid-State Fermentation of Oat Straw to Enhance Physical Quality of Pellets

Abstract

Pelleting can increase the efficiency of handling and transportation of biomass. Pretreatment obtains lignin fragments by disrupting the lignocellulosic structure of biomass and ensures the high-quality compressed pellets. In this study, solid-state fermentation (SSF) is used as a biological method to improve the quality of pellets of oat straw. SSF of oat straw using Trametes versicolor 52J (TV52J) and Phanerochaete chrysosporium (PC) was conducted. Response surface methodology (RSM) was employed by using a four-factor, three-level Box–Behnken design with fermentation time (days), moisture content (%), particle size (mm), and fermentation temperature (°C) as independent parameters. Pellet density, dimensional stability, and tensile strength were the response variables. The optimization options of fermentation time (33.96 and 35 days), moisture content (70%), particle size (150 and 50 mm), and fermentation temperature (22°C) of oat straw pretreated with these two fungal strains were obtained. The microscopic structural changes of oat straw caused by biological pretreatment were investigated by scanning electron microscopy (SEM). Observation results of SEM showed that the connection between single fibers became relatively loose, and this was beneficial to improve the physical quality of the pellets.

Comparative Study on Quality of Fuel Pellets from Switchgrass Treated with Different White-Rot Fungi

“…Gao et al [28] studied the physical quality of pellets from fungal-pretreated wheat straw and reported that fermentation temperature and time had significant effects on the pellet tensile strength and pellet unit density, which buttresses the findings of this present study. A significant effect of fermentation time on the tensile strength and unit density of pellets from TV52J-and PC-pretreated biomass was also recorded in similar studies by Gao et al [38] on oat straw and Gao et al [27] on corn stover. independent variables at a constant level.…”

“…However, lower temperatures require longer fermentation times than the TV52J treatment at higher temperature. The optimum fermentation time reported in this study was in a close range with the optimum fermentation time obtained for the solid-state fermentation of oat straw using the same fungal strains [38]. Although the 21 d fermentation time reported in this present study is long relative to other pretreatment methods [43,44], it represents a significant reduction in fermentation time considering the 84 d of fermentation reported by Canam et al [22] and Kalinoski et al [23] using TV52J and the mutant strain (m4D).…”

High Potential Organic Feedstocks for Production of Renewable Solid Briquettes-A Comprehensive Review

“…On the other hand, Fuel characteristics of oat straw pellets treated with Phanerochaete chrysosporium are as follows: density (immediate and after 14 days)-1108 kg/m 3 and 1068 kg/m 3 , Dimensional stability-1.14 %, Tensile strength-0.294 MPa for a fermentation duration and temperature of 35 days and 22 o C, with MC and particle size maintained as 70% and 50 mm, respectively. Overall, this study concluded that pre-treating biomass using microorganisms also helped in improvising the fuel characteristics, upon compaction (Gao et al, 2020).…”

“…In another interesting study by Gao et al, 2020, oat straw were compacted into pellets, post treating it with fungal species namely: Trametes versicolor 52J and Phanerochaete chrysosporium. This study used Single pelleting unit operated at 4KN compaction pressure and produced pellets with dimension as follows: length-; diameter-.…”

Unleashing the Ligno-Hemicellulolytic Enzyme Potential of Pyrenophora phaeocomes S-1: A Solid State Fermentation Approach for Efficient Delignification of Corn Stover

“…Solid-state fermentation represents a promising approach for the production of enzymes, as it offers the potential for recycling agro-industrial waste and simultaneously facilitates the delignification process, resulting in the generation of valuable products [27]. In this study, the fungal strain P. phaeocomes S-1 exhibited the ability to initiate the production of all three enzyme components of the enzyme cocktail within 24 h of incubation.…”