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## Meet the editor

Dr. J. Rajesh Banu, Assistant Professor, Department of Civil Engineering, Anna University Regional Campus Tirunelveli, was formerly a postdoctoral fellow and lecturer in the Department of Civil and Environmental Engineering, Sungkyunkwan University, South Korea. He received his PhD from the Centre for Environmental Studies, Anna University, India, in 2006. He also had experience of working in environmental consultancy for

one year. He has been a reviewer of many national and international journals and is the author of 160 publications in SCI and SCIE journals with a cumulative impact factor of 550. His publications achieve more than 3000 citations and he has an H-index of 31. He has authored 20 book chapters for international publishers. Dr. Banu obtained two major grants from the Government of India and two consultancies from industries. He has guided 12 PhD students and 60 postgraduate engineering students in the discipline of environmental engineering and science. He was awarded with Young Scientist in an international conference (RACEE-2018) held at SSN college, Chennai, India. Dr. Banu's research centers on biological wastewater treatment, nutrient removal, membrane bioreactor mesophilic and thermophilic high-rate anaerobic treatment of wastewater, microbial fuel cells, energy recovery from waste, and sludge reduction. His prime area of research is the generation of energy from solid waste.

Contents

**Section 1**

**Section 2**

Production Systems

of the Key Enzymes

*and Zulay Niño-Ruiz*

Anaerobic Digestion

**Section 3**

*and Mieczysław Błaszczyk*

**Preface III**

Introduction **1**

**Chapter 1 3**

Anaerobic Digestion **11**

**Chapter 2 13**

**Chapter 3 49**

**Chapter 4 69**

Anaerobic Digestion Improvement and Evaluation **89**

**Chapter 5 91**

**Chapter 6 113**

Techno-Economic Analysis of Biogas Production from Microalgae through

*by Na Wu, Cesar M. Moreira, Yingxiu Zhang, Nguyet Doan, Shunchang Yang, Edward J. Phlips, Spyros A. Svoronos and Pratap C. Pullammanappallil*

Searching for Metabolic Pathways of Anaerobic Digestion: A Useful List

*by Anna Sikora, Anna Detman, Damian Mielecki, Aleksandra Chojnacka* 

Review of Mathematical Models for the Anaerobic Digestion Process *by Borja Velázquez-Martí, Orlando W. Meneses-Quelal, Juan Gaibor-Chavez* 

Biomass Pretreatment for Enhancement of Biogas Production *by Tamilarasan Karuppiah and Vimala Ebenezer Azariah*

Microbial Responses to Different Operating Practices for Biogas

Introductory Chapter: An Overview of Biogas *by J. Rajesh Banu and R. Yukesh Kannah*

*by Maria Westerholm and Anna Schnürer*

## Contents



Preface

The rapid increase in global energy demand has resulted in shortages of fossil fuel supply. Biogas is the most profitable bioenergy generated from first-, second-, and third-generation waste biomass, is the best suitable alternative to fossil fuel, and is cost effective. Biogas consists of approximately 60–65% methane, 25–30% carbon dioxide, and a small amount of toxic gases, etc. Organic waste management via anaerobic digestion is the most commonly preferred technique. During this process the anaerobic microbes play a vital role in conversion of organic waste into biogas. To enhance biogas production, pretreatment prior to anaerobic digestion results in achieving a positive energy yield. Developing a proper system to recover biogas from organic waste will reduce global warming issues. This book intends to provide a comparative overview of a recent update in biogas production, processing, and its application in various sectors. In addition, this book contains several scientific discussions regarding microbes involved in biogas production, processing, and recent technologies for sustainable development. The book provides in-depth information about anaerobic digestion to researchers and graduate students. The editor sincerely thanks all the contributors, whose efforts have brought this book to

**Dr. J. Rajesh Banu**

Tirunelveli, India

Department of Civil Engineering, Anna University Regional Campus,

fruition.
