Process considerations of a biorefinery producing value-added products from corn fibre

Abstract

Corn fibre, a co-product of corn wet milling, can be a suitable raw material of a biorefinery producing biofuels and valueadded chemicals. The simulated process is able to produce bioethanol, biomethane and xylitol synergistically, while it also covers its own heat demand. The proposed plant consists of the following process steps: fractionation, enzymatic hydrolysis and ethanol fermentation, distillation and dehydration, anaerobic digestion, biogas upgrading, aerobic waste water treatment, combined heat and power production, xylitol fermentation and recovery. Various scenarios of the biorefinery were investigated and the process configurations were compared in terms of energy efficiency, or mass flows of the products. Incineration of the sludge and production of district heat are found to be effective methods to increase the energy efficiency, on which aerobic sludge yield has a great effect. The solid-liquid separations, which are carried out in filterpress, have a curial role in terms of energy efficiency. Combustion of the solid part of cellulose hydrolysis residue is favourable compared with the anaerobic digestion, except if the dry matter content of the filterpressed solid was set to 30% instead of 40%. The amounts of the produced xylitol and biomethane are variable, which ensures the ability of market adaptation for the biorefinery.

Investigation of selective arabinose release from corn fibre by acid hydrolysis under mild conditions

“…where Y represents the response variable, b 0 is the intercept, b 1 and b 2 are the linear coefficients, b 11 and b 22 are the quadratic terms and X 1 and X 2 represent the independent variables studied. The independent variables were expressed in original physical values.…”

“…Corn fibre is utilized mainly as low‐value animal feed, or solid fuel in pelletized form, however, it is a promising raw material for producing value‐added products . The main fields of research concerning corn fibre utilization are the production of bioethanol and food additives like cellulosic fibre gel, corn fibre gum, xylo‐oligosaccharide prebiotics, corn fibre oil, ferulic acid, xylitol and vanillin .…”

The role of the particle size reduction and morphological changes of solid substrate in the ultrasound-aided enzymatic hydrolysis of cellulose

“…and the parameters of hydrolysis (substrate and enzyme loading, temperature, duration, etc.) [3] , [4] , [5] . Among the several factors that can have a significant effect on the rate of enzyme-catalyzed depolymerization, the substrate properties were found to be limiting, since the accessibility of cellulose to the enzyme depends on the physical–chemical and structural parameters of the cellulosic material [6] , [7] .…”

Investigation of commercial enzyme preparations for selective release of arabinose from corn fibre

“…Corn fibre, a low‐value by‐product of the corn wet milling process, is an appropriate raw material for producing sugars including L‐arabinose . Corn fibre has been used as a low‐grade animal feed ingredient or as solid fuel in pelletized form, however it can also be converted into value‐added products in a biorefinery concept . Corn fibre dry matter contains about 20% starch, 14% cellulose and 35% hemicellulose .…”

“…8 -13 Corn fibre has been used as a low-grade animal feed ingredient or as solid fuel in pelletized form, however it can also be converted into value-added products in a biorefinery concept. 14 -16 Corn fibre dry matter contains about 20% starch, 14% cellulose and 35% hemicellulose. 17 The hemicellulose fraction consists of a xylan backbone, which is highly substituted with monomeric side-chains of L-arabinose, acetic acid and D-glucuronic acid, and with oligomeric side-chains containing L-arabinose, D-xylose and D-galactose.…”