Preface

Solid waste management is one of the important disciplines of environmental management. It is divided into two parts, dealing with biodegradable and nonbiodegradable waste. The segregation of waste in most developing countries is a difficult task. This problem has a wide range of causes, including the lack of public knowledge of the problem. Lack of funds plays a small but very vital role.

Solid waste management is a wide and diversified field. Within this field, organic waste attracts a great deal of attention because of its chemical constituents. However, the few narrowly specialized resources on this type of waste are insufficient to reveal the complete chemistry of it. The book titled "Management of Organic Waste *"* is designed to provide a fundamental knowledge of the principles related to the management of organic waste. The chapters of the book are arranged logically and they offer an up-to-date approach to offer a better understanding of the chemistry used to treat organic waste as a raw material which results in a useful product. The breadth and depth of the material presented in this book will help to understand the different processing and disposal aspects of organic waste. The comparative aspects of processing and disposal, reflect the unique identity of the book. Lastly, each chapter with different sub-headings contains very good resources, and very clear concepts.

This publication will be extremely helpful to students, researchers, scientists, policy makers, and local waste management authorities.

#### **Er Sunil Kumar, Scientist**

Council of Scientific and Industrial Research-National Environmental Engineering Research Institute (CSIR-NEERI), Kolkata Zonal Laboratory Kolkata, West Bengal, India

#### **Dr Ajay Bharti, Assistant Professor**

North Eastern Regional Institute of Science & Technology [NERIST] Nirjuli, Itanagar Arunachal Pradesh India

**Part 1** 

**Biogas from Organic Waste** 

**Part 1** 

**Biogas from Organic Waste** 

**1** 

*Slovenia* 

**Anaerobic Treatment and** 

Gregor D. Zupančič and Viktor Grilc *Institute for Environmental Protection and Sensors* 

**Biogas Production from Organic Waste** 

Organic wastes under consideration are of natural origin that possess biochemical characteristics ensuring rapid microbial decomposition at relatively normal operating conditions. When considering the organic waste treatment we have generally in mind organic mineralization, biological stabilisation and detoxification of pollutants. Most common organic wastes contain compounds that are mainly well biodegradable. They can be readily mineralized either through biological treatment (aerobic or anaerobic), or thermo chemical treatment such as incineration, pyrolysis and gasification. The latter will not be treated in this work. Most organic wastes produced today originate in municipal, industrial and agricultural sector. Municipal waste (as well as municipal wastewater sludge) is generated in human biological and social activities and contains a large portion of organic waste readily available for treatment. Agricultural waste is common in livestock and food production and can be utilised for biogas production and therefore contribute to more sustainable practice in agriculture. Industrial wastes arise in many varieties and are the most difficult for biological treatment, depending of its origin. Namely, many industries use chemicals in their production in order to achieve their product quality and some of these chemicals are present in the waste stream, which is consequently difficult to treat. Recently, organic waste treatment has had a lot of attention, due to possibilities of energy recovery from these wastes as well as to prevent their adverse environmental effects. Energy recovery is possible through controlled release of chemically bound energy of organic compounds in waste and can be retrieved through chemical and biochemical processes. Most of the organic wastes appear in solid form; however contain up to 90% of moisture, therefore thermochemical treatment such as incineration cannot be applied. To address sustainability in the treatment of organic wastes, environmental aspect, energy aspect and economical aspect of

Biodegradable organic waste can be treated with or without air access. Aerobic process is composting and anaerobic process is called digestion. Composting is a simple, fast, robust and relatively cheap process producing compost and CO2 (Chiumenti et al. 2005, Diaz et al. 2007). Digestion is more sophisticated, slow and relatively sensitive process, applicable for selected input materials (Polprasert, 2007). In recent years anaerobic digestion has become a prevailing choice for sustainable organic waste treatment all over the world. It is well suited for various wet biodegradable organic wastes of high water content (over 80%), yielding

**1. Introduction** 

the treatment processes should be considered.

methane rich biogas for renewable energy production and use.
