Biomass Preprocessing And Pretreatments For Production Of Biofuels

Engineering the physical, chemical, and energy properties of lignocellulosic biomass is important to produce high-quality consistent feedstocks with reduced variability for biofuels production. The emphasis of this book will be the beneficial impacts that mechanical, chemical, and thermal preprocessing methods can have on lignocellulosic biomass quality attributes or specifications for solid and liquid biofuels and biopower production technologies. "Preprocessing" refers to treatments that can occur at a distance from conversion and result in an intermediate with added value, with improved conversion performance and efficiency. This book explores the effects of mechanical, chemical, and thermal preprocessing methods on lignocellulosic biomass physical properties and chemical composition and their suitability for biofuels production. For example, biomass mechanical preprocessing methods like size reduction (which impacts the particle size and distribution) and densification (density and size and shape) are important for feedstocks to meet the quality requirements for both biochemical and thermochemical conversion methods like enzymatic conversion, gasification, and pyrolysis process. Thermal preprocessing methods like drying, deep drying, torrefaction, steam explosion, hydrothermal carbonization, and hydrothermal liquefaction effect feedstock's proximate, ultimate and energy property, making biomass suitable for both solid and liquid fuel production. Chemical preprocessing which includes washing, leaching, acid, alkali, and ammonia fiber explosion that can enable biochemical composition, such as modification of lignin and hemicellulose, and impacts the enzymatic conversion application for liquid fuels production. This book also explores the integration of these preprocessing technologies to achieve desired lignocellulosic biomass quality attributes for biofuels production.

The increasing global demand for energy requires a versatile approach, prompting many researchers to focus on renewable bioenergy from different biomasses, especially cellulosic biomass. Such biomasses can be agricultural wastes, municipal wastes or direct harvests from high-yield energy corps. If properly pre-treated, the subsequent enzyme hydrolysis step is much more effective and can effectively minimises the waste disposal. Green Biomass Pretreatment for Biofuels Production reviews a range of pretreatment methods such as ammonium fiber explosion, steam explosion, dilute acid hydrolysis, alkali hydrolysis, and supercritical carbon dioxide explosion focusing on their final sugar yields from hemicellulose, glucose yields from cellulose, as well as on their feasibilities in bioenergy production processes at various scales. This book emphasises the tactical mobile and on-farm scales applications that use green pretreatments and processing technologies without the need of on-site waste treatment. Because of the varieties of different biomasses, no single pretreatment is expected to be the universal choice. Some of the pretreatment methods present niche applications are also discussed.

Engineering the physical, chemical, and energy properties of lignocellulosic biomass is important to produce high-quality consistent feedstocks with reduced variability for biofuels production. The emphasis of this book will be the beneficial impacts that mechanical, chemical, and thermal preprocessing methods can have on lignocellulosic biomass quality attributes or specifications for solid and liquid biofuels and biopower production technologies. "Preprocessing" refers to treatments that can occur at a distance from conversion and result in an intermediate with added value, with improved conversion performance and efficiency. This book explores the effects of mechanical, chemical, and thermal preprocessing methods on lignocellulosic biomass physical properties and chemical composition and their suitability for biofuels production. For example, biomass mechanical preprocessing methods like size reduction (which impacts the particle size and distribution) and densification (density and size and shape) are important for feedstocks to meet the quality requirements for both biochemical and thermochemical conversion methods like enzymatic conversion, gasification, and pyrolysis process. Thermal preprocessing methods like drying, deep drying, torrefaction, steam explosion, hydrothermal carbonization, and hydrothermal liquefaction effect feedstock's proximate, ultimate and energy property, making biomass suitable for both solid and liquid fuel production. Chemical preprocessing which includes washing, leaching, acid, alkali, and ammonia fiber explosion that can enable biochemical composition, such as modification of lignin and hemicellulose, and impacts the enzymatic conversion application for liquid fuels production. This book also explores the integration of these preprocessing technologies to achieve desired lignocellulosic biomass quality attributes for biofuels production.

The success of lignocellulosic biofuels and biochemical industries depends upon an economic and reliable supply of quality biomass. However, research and development efforts have historically focused on the utilization of agriculturally-derived, cellulosic feedstocks without consideration of their low energy density, high variations in physical and chemical characteristics and potential supply risks in terms of availability and affordability. This Research Topic will explore strategies that enable supply chain improvements in biomass quality and consistency through blending, preprocessing, diversity and landscape design for development of conversion-ready, lignocellulosic feedstocks for production of biofuels and bio-products. Biomass variability has proven a formidable challenge to the emerging biorefining industry, impeding continuous operation and reducing yields required for economical production of lignocellulosic biofuels at scale. Conventional supply systems lack the preprocessing capabilities necessary to ensure consistent biomass feedstocks with physical and chemical properties that are compatible with supply chain operations and conversion processes. Direct coupling of conventional feedstock supply systems with sophisticated conversion systems has reduced the operability of biorefining processes to less than 50%. As the bioeconomy grows, the inherent variability of biomass resources cannot be managed by passive means alone. As such, there is a need to fully recognize the magnitude of biomass variability and uncertainty, as well as the cost of failing to design feedstock supply systems that can mitigate biomass variability and uncertainty. A paradigm shift is needed, from biorefinery designs using raw, single-resource biomass, to advanced feedstock supply systems that harness diverse biomass resources to enable supply chain resilience and development of conversion-ready feedstocks. Blending and preprocessing (e.g., drying, sorting, sizing, fractionation, leaching, densification, etc.) can mitigate variable quality and performance in diverse resources when integrated with downstream conversion systems. Decoupling feedstock supply from biorefining provides an opportunity to manage supply risks and incorporate value-added upgrading to develop feedstocks with improved convertibility and/ or market fungibility. Conversion-ready feedstocks have undergone the required preprocessing to ensure compatibility with conversion and utilization prior to delivery at the biorefinery and represent lignocellulosic biomass with physical and chemical properties that are tailored to meet the requirements of industrially-relevant handling and conversion systems.

This monograph discusses the various biomass feedstocks currently available for biofuels production, and mechanical preprocessing technologies to reduce the feedstock variability for biofuels applications. Variability in the properties of biomass—in terms of moisture, particle size distribution, and low-density—results in storage, transportation, handling, and feeding issues. Currently, biorefineries face serious particle bridging issues, uneven discharge, jamming of equipment, and transportation problems. These issues must be solved in order for smooth operations to be possible. Mechanical preprocessing technologies, such as size reduction, densification, and moisture management using drying and dewatering, can help to overcome these issues. Many densification systems exist that will assist in converting low-density biomass to a high-density commodity type feedstock. In 6 chapters, the impact of densification process variables, such as temperature, pressure, moisture, etc., on biomass particle agglomeration, the quality of the densified products, and the overall energy consumption of the process are discussed, as are the various compression models for powders that can be used for biomass particles agglomeration behavior and optimization of the densification process using statistical and evolutionary methods. The suitability of these densified products for biochemical and thermochemical conversion pathways is also discussed, as well as the various international standards (CEN and ISO) they must adhere to. The author has worked on biomass preprocessing at Idaho National Laboratory for the last ten years. He is the principal investigator for the U.S. Department of Energy Bioenergy Technologies Office-funded “Biomass Size Reduction and Densification” project. He has developed preprocessing technologies to reduce cost and improve quality. The author has published many papers and books focused on biomass preprocessing and pretreatments. Biomass process engineers and biorefinery managers can benefit from this book. Students in chemical, mechanical, biological, and environmental engineering can also use the book to understand preprocessing technologies, which greatly assist in improving the biomass critical material attributes. The book can help policymakers and energy systems planners to understand the biomass properties limitations and technologies to overcome the same.

This book addresses the developing area of biomass for technological applications. Written by leading researchers in the field, the book differs from other literature available by providing a detailed, in-depth discussion of the characteristics of these materials. The use of biomass for technological applications is a rapidly growing area in materials engineering and green bioprocesses. In this approach, pre-treatments focus on the bioavailability of nutrients and facilitate the use of biomass for delivering byproducts (e.g. enzymes) and for bioenergy production, both of which are discussed at length in this book. In this regard, it explores various aspects of the structural complexity of residual biomass produced by agricultural, industrial and livestock activities for biotechnological purposes, and assesses both conventional and emerging pre-treatments (e.g. biological, enzymatic and physical–chemical). This book reveals the advantages of these techniques, both individually and in combination, making it an excellent resource for all readers interested in cutting-edge applications of biomass.

Biofuels production is one of the most extensively studied fields in the energy sector that can provide an alternative energy source and bring the energy industry closer to sustainability. Biomass-based fuel production, or renewable fuels, are becoming increasingly important as a potential solution for man-made climate change, depleted oil reserves, and the dangers involved with hydraulic fracturing (or “fracking”). The price of oil will always be volatile and changeable, and, as long as industry and private citizens around the world need energy, there will be a need for alternative energy sources. The area known as “biofuels and biofeedstocks” is one of the most important and quickly growing pieces of the “energy pie.” But biofuels and biofeedstocks are constantly changing, and new processes are constantly being created, changed, and improved upon. The area is rapidly changing and always innovative. It is important, therefore, that books like the volumes in this series are published and the information widely disseminated to keep the industry informed of the state-of-the-art. This second volume in the Advances in Biofeedstocks and Biofuels series focuses on the production of biofuel, covering all of the major biofuels, such as biodiesel, biohydrogen, bioethanol, and others. This engaging text touches on all of the most important new processes and technologies, providing the most up-to-date coverage of the science available to industry. It is a must-have for any engineer or scientist working with biofuel technology.

The book describes the pretreatment of lignocellulosic biomass for biomass-to-biofuel conversion processes, which is an important step in increasing ethanol production for biofuels. It also highlights the main challenges and suggests possible ways to make these technologies feasible for the biofuel industry. The biological conversion of cellulosic biomass into bioethanol is based on the chemical and biological breakdown of biomass into aqueous sugars, for example using hydrolytic enzymes. The fermentable sugars can then be further processed into ethanol or other advanced biofuels. Pretreatment is required to break down the lignin structure and disrupt the crystalline structure of cellulose so that the acids or enzymes can easily access and hydrolyze the cellulose. Pre-treatment can be the most expensive process in converting biomass to fuel, but there is great potential for improving the efficiency and lowering costs through further research and development. This book is aimed at academics and industrial practitioners who are interested in the higher production of ethanol for biofuels.