Progressive Thermochemical Biorefining Technologies

Sonil Nanda, Dai-Viet N. Vo

• Publisher: CRC Press
• Year: 2021
• Print ISBN:
  9780367566098
• eBook ISBN:
  9781000427431
• Topic: Technology & Engineering
• Subtopic: Biotechnology
• Index: Technology & Engineering

Considering the deleterious impacts of fossil fuels on the environmental and natural ecosystems, it has become imperative to make a paradigm shift toward renewable fuels, chemicals, and materials. The exhaustive everyday usage of fossil fuels and processed petrochemical products are the leading causes for the increase in greenhouse gas emissions, global warming, climate changes, acid rain, ozone layer depletion, pollution of air, water, and soil as well as for the accumulation of nonbiodegradable materials in the soil and oceans. On the contrary, biofuels, biochemicals, and biomaterials derived from renewable wastes such as nonedible plant biomass (e.g., agricultural and forestry biomass), energy crops, microalgae, municipal solid waste, sewage sludge, and other biogenic residues seem to be carbon neutral. Therefore, the global interest in biorefining technologies, especially thermochemical and biological conversion processes, is gaining momentum in academic and industrial perspectives.

Progressive Thermochemical Biorefining Technologies offers all-inclusive coverage of the most crucial topics as follows:

• State-of-the-art information on the production and utilization of biofuels through thermochemical biorefining technologies
• Conversion of waste biomass through pyrolysis, liquefaction, torrefaction, carbonization, gasification, reforming, and other clean technologies
• Waste-to-energy/chemical generation
• Fuel upgrading technologies
• Techno-economic analysis and life-cycle assessment of biorefining processes

Specifically designed to be instantly applicable, this volume serves as a reference book for undergraduate and graduate students, scientific investigators, and research scholars working in the areas relating to energy and fuels.

1

Thermochemical and Biological Conversion of Biomass into Biofuels and Biochemicals

Munusamy Subathra, Narasiman Nirmala, Shanmuganantham Selvanantham Dawn, Sivaprasad Shyam, Kannappan Panchamoorthy Gopinath and Jayaseelan Arun

Contents

• 1.1 Introduction
• 1.2 Waste Biomass
• 1.3 Composition and Properties of Biomass
  • 1.3.1 Cellulose, Hemicellulose, and Lignin
  • 1.3.2 Moisture Content
  • 1.3.3 Ash and Alkali Metal Content
  • 1.3.4 Bulk Density
• 1.4 Thermochemical Conversion Pathways for Biofuel Production
  • 1.4.1 Liquefaction
  • 1.4.2 Pyrolysis
• 1.5 Biological Conversion Pathway for Biofuel Production
  • 1.5.1 Syngas Fermentation
  • 1.5.2 Fermentation of Biomass
• 1.6 Conclusions
• Acknowledgments
• References

1.1 Introduction

Global energy demand has drastically increased due to rapid industrialization and explosion in the human population straining the conventional petroleum-based energy sector which contributes about 80–85% of energy needs of the world (Ong et al., 2020; Saravanan et al., 2020). Moreover, increasing environmental awareness among people and focus on achieving the United Nation’s Sustainable Development Goals (SDGs) are propelling the need to utilize renewable energy from biomass (Omer and Noguchi, 2020; Pang, 2019). Biomass has an edge over other renewable sources as it is abundantly available and can be utilized for generating heat, electricity, transportation-grade fuels, platform chemicals, and other value-added products. In addition, utilizing biomass will create room for the growth of new biomass, and waste biomass can be potentially valorized for beneficial purposes (Ibarra-Gonzalez and Rong, 2019). There are several strategies for valorizing biomass as depicted in Figure 1.1. Thermochemical conversion of biomass essentially requires liquefaction, pyrolysis and gasification to produce biochar, bio-oil, syngas and other value-added chemical intermediates such as 5-hydroxymethylfurfural (HMF) and furfural (Gao et al., 2020; Yang et al., 2019). Biological conversion of biomass requires fermentation to produce bioethanol and requires anaerobic digestion to produce biogas (El-Dalatony et al., 2019; Ge et al., 2014; Hawkins et al., 2013).

Figure 1.1 Biomass conversion pathways for the production of value-added compounds.

1.2 Waste Biomass

Biomass is widely used as a source for the production of renewable biofuels. Biomass is usually produced naturally, and it is considered an organic material, as it is obtained from the remains of plants and animals. Both plants and animals are the best sources of sugar residues. In general, the plant and algal materials that are considered as the primary sources of energy utilize the sunlight and produce carbohydrate and water by the process called photosynthesis. Carbohydrate and water are further converted into primary and secondary metabolites, which include cellulose, hemicelluloses, lignin, and starch that are widely used in various industrial sectors. The carbohydrate residues help in producing various biofuels which include bioethanol, biobutanol, heat energy, electrical energy, etc. (Huber et al., 2006; Naik et al., 2010). Renewable energy obtained from biomass thus not only fulfills the energy demand but also decreases the amount of waste disposed as all the organic waste can be utilized as the source for the production of bioenergy (Sims et al., 2008).

Wastes such as municipal solid waste, food waste, agricultural waste, and sewage waste come under the category of bio-renewable waste, which can be used as biomass due to the presence of high-energy-producing substances. Such waste can be utilized for the production of bioenergy by using various techniques such as fermentation process and thermochemical process. (Okolie et al., 2020; Arun et al., 2020). Food waste, fruit peel waste, agricultural waste, etc., are considered as the primary source of starch which can yield biogas, bioethanol, bio-crude, etc., by the anaerobic fermentation process. Sugar crops, oilseed crops, starch crops, etc., can be converted to biodiesel or bio-crude by the process of transesterification or hydrothermal liquefaction process. The residue can be used as the soil conditioner.

Forest products such as wood residues, tree barks, shrubs, sawdust can undergo thermal treatment, which results in the formation of heat energy that can be further converted into electrical energy. The ash that remains as a result of the thermal treatment is a rich source of minerals. On the application of the produced ash over soil, the mineral content increases, and it conditions the soil to increase its fertility and yields high crop growth. Most of the paper industry uses the process of the thermal treatment of wood residue to produce electricity for its use.

1.3 Composition and Properties of Biomass

1.3.1 Cellulose, Hemicellulose, and Lignin

The amount of bio-crude or bio-oil produced from the biomass depends majorly on the biodegradability of the cellulose or hemicelluloses or lignin content present. The cellulose has higher biodegradability than the lignin content and hemicelluloses, which acts as a major criterion for choosing the raw material for any thermal conversion or biological conversion process. The cellulose-rich biomass gives a higher yield, but the lignin-rich biomass provides higher energy on carrying out hydrolysis or enzymatic conversion process.

Table 1.1
Biomass and Its Category

Category of Biomass	Biomass Source
Bio-renewable wastes as biomass	Food waste
	Agricultural waste
	Urban organic waste
	Municipal solid waste
	Mill wood waste
	Sewage waste
Crops producing energy	Starch ...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• Preface
• Editors
• Contributors
• 1. Thermochemical and Biological Conversion of Biomass into Biofuels and Biochemicals
• 2. Solid and Liquid Biofuels from Waste and Biomass: Production, Characterization and Combustion
• 3. Conversion of Municipal Solid Waste to Biofuels
• 4. Conversion of Plastic Waste to Fuels and Chemicals
• 5. Torrefied Solids: A Material Border Lining Biomass and Biochar
• 6. Pelletization of Torrefied Biomass Using Binders
• 7. Lignocellulosic Biomass Conversion to Syngas through Co-Gasification Approach
• 8. Glycerol: A Promising Green Source for Chemicals and Fuels
• 9. Effect of Substrates on the Performance of Microbial Fuel Cell for Sustainable Energy Production
• 10. Oil Price Shocks, Environmental Pollution, Foreign Direct Investment, and Renewable Energy Consumption: An Empirical Analysis in East Asian Countries
• Index