eChapters

8.1 Introduction

Biogas is produced by the anaerobic digestion of biodegradable materials with the help of microorganisms. Biogas is also considered as renewable energy source because of is environment friendly nature. Conversion of cattle dung, kitchen wastes and agricultural wastes into biogas have the potential to minimize the burden on the fossil fuel and reduce the environmental pollution. Majority of developing countries specially their rural and suburban areas faces lack of access to the electricity and cooking gas. Biogas technology is emerging as a sustainable technology for waste treatment which could help to tackle the waste disposal issue in developing countries. 

Abstract

Since the first oil well drilled successfully in 1859, crude oil has been a serious problem around world, including Indonesia. As a source of all petroleum products, crude oil is very complex component and divided into aliphatic, aromatic, resin and asphaltene. Petroleum products have been used for daily life and created large amounts of pollutants in environment and ecosystems around the globe. The pollutants should be treated by certain method; among them, bioremediation has several advantages to resolve the problem. In 2003, Ministry of Environmental (MoE) – Republic Indonesia was endorsed with a new regulation about biological treatment or bioremediation for crude oil contaminated soil (MoE regulation No. 128/2003). The most important to be noted in bioremediation process is the presence of microbes with certain metabolite capabilities. The degradation rate also can be improved and sustained by ensuring the adequate required factors. This article describes the removal of crude oil by utilization of microbial potentials, factors affecting biodegradation, and how they are applied in Indonesia.

Abstract

Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. The constantly changing today’s world of technology has led to the serious problem of e-waste. The previous studies show that India has generated 0.6 million tons of e-waste in 2014 which may increase to 0.7 to 0.9 million tons by 2015–2016. E-waste constitutes multiple components some of which are toxic that can cause serious health and environmental issues if not handled properly. The challenge is to develop innovative and cost-effective solutions to decontaminate polluted environments, to make them safe for human habitation and consumption, and to protect the functioning of the ecosystems which support life. Biological approach is currently applied to recovery of metals from contaminated soil, groundwater, surface water, and sediments including air.

Abstract

Mine spoils pose adverse conditions for soil microbes and plant growth, due to its low organic content and other essential nutrients, unfavourable soil chemistry and poor soil texture. Poor microbial population inhibits nutrient transformation, consequently the establishment of the plants and ultimately affects the process of ecological succession. A synergy among different groups of beneficial microbes accompanied by plantation of suitable tree species on mined over area has proved to be effective for speedy and efficient revitalization of the mined affected lands. Inoculation of plantation with efficient strains of native microbes accelerates the soil redevelopment and helps to establish nutrients cycle readily which attracts native flora thereby the pace of natural regeneration is increased. It is therefore imperative to consider the application of effective microflora in restoration of mined lands along with the plantation.

Biomass briquetting is the process of compressing loose and low-density biomass materials such as sawdust, agricultural residues, and forest waste into high-density, solid fuel blocks called briquettes. The process involves mechanical compression under high pressure using machines like piston presses, screw extruders, or hydraulic presses, depending on the technology used.
The main purpose of briquetting is to increase the density of biomass to improve its combustion properties, handling, transportation, and storage efficiency. In most modern systems, briquetting is done without the use of binders, as natural lignin present in the biomass acts as a binding agent under pressure and heat.
Importance of Biomass Briquetting
Biomass briquetting holds immense environmental, economic, and social importance.
1. Environmental Protection
• Briquetting reduces deforestation by providing an alternative to firewood and charcoal.
• It minimizes air pollution by producing cleaner-burning fuel with lower particulate emissions and sulfur content.
• The process helps in carbon sequestration by ensuring the
sustainable use of biomass.
2. Waste Management
• Agricultural residues like rice husk, sugarcane bagasse, cotton stalks, and sawdust, which otherwise cause disposal problems, are effectively utilized.

5.1 Introduction

The densification of biomass involves transforming loose and low-density organic materials, such as wood residues, agricultural waste, and plant-based materials, into compact and energy-dense forms. This process is necessary because natural biomass can be challenging to handle, transport, and store. Densification uses mechanical, thermal, or chemical processes to increase the material’s density and energy characteristics. The resulting products, such as pellets, briquettes, or cubes, offer several advantages, including higher energy content per unit volume, efficient storage and transportation, reduced moisture content, and improved combustion efficiency. These products are utilized in various industries, including energy production, residential heating, waste management, and industrial applications. Biomass densification promotes sustainable practices by effectively utilizing biomass resources, reducing waste, and promoting the use of renewable energy sources while mitigating environmental impacts.

2.1 Introduction

Biomass store solar energy in the chemical form and it is most precious and versatile resources on earth. Biomass, unlike fossil fuels, is a renewable energy resource that is available where the climatic conditions are favorable for plant growth and production¹. The term biomass is used for all organic materials which are combustible in nature, mainly plant and animal origin present in land and aquatic environments. Biomass is considered carbon neutral, because the amount of carbon it can release is equivalent to the amount it absorbed during its life time. There is no net increase of carbon to the environment in the long term when combusting the lignocellulosic materials. Therefore, we can say that biomass is a renewable source of energy and can play vital role in responding to concerns over the protection of the environment and the security of energy supply^2,3.

Biomass energy accounts for about 15% of the world’s primary energy consumption and about 38% of the primary energy consumption in developing countries⁴. Furthermore, biomass often accounts for more than 90% of the total rural energy supplies in developing countries⁵. It is the main source to meet out domestic energy in developing countries⁶. The efficient use of fuel wood is much more eco-friendly than the use of efficient and conventional fuels like kerosene and liquefy petroleum gas (LPG). LPG emits 15 times more CO₂ per kg than wood, and kerosene emits nearly 10 times as much. CO₂ is the prominent candidate for global. It is commonly assumed that biomass fuel cycles based on renewable in nature and greenhouse-gas (GHG) neutral because the combusted carbon in the form of CO₂ is soon taken up by re-growing vegetation⁷.

5.1 Introduction

Biomass energy is the energy obtained from biomass or living things. Biomass is renewable organic material that comes from plants and animals. Plants generally produced through the process of photosynthesis as shown in Figure 5.1. Biomass is organic, meaning it is made of material that comes from living things, such as plants and animals. Wood, plants, and waste are the most common biomass energy sources. These are called biomass feedstocks. A plant absorbs the sun’s energy through photosynthesis and converts carbon dioxide and water into nutrients (carbohydrates). The energy from these materials can be transformed into usable energy through direct and indirect means. Biomass can be burned to create heat (direct), converted into electricity (direct), or processed into biofuel (indirect).

7.1 Introduction

Biomass gasification is age old technology originated in 1800 century for lighting and cooking purposes (Sansaniwal et al., 2017). Biomass typically contents biopolymers such as cellulose, hemicellulose and lignin in addition to the presence of average composition of C₆H₁₀O₅ which depends upon physical characteristics of biomass¹. Oxygen is required for combustion of every fuel. For complete combustion of biomass stoichiometric air to fuel ratio required varies from 6:1 to 6.5:1 with CO₂ and H₂O as end product.

Biomass gasification is an efficient and environmentally friendly way to produce energy². Gasification process is nothing but it is a conversion of solid fuel into gaseous fuel for wide applications. This whole process completed at elevated temperature range of 800-1300 ^oC with series of chemical reaction that is why it come under thermo chemical conversion³. Thermo chemical processes are most commonly employed for converting biomass into higher heating value fuels⁴. Major thermal conversion route is include direct combustion to provide heat, liquid fuel and other elements to generate process heat for thermal and electricity generation is summaries in Fig. 7.1.

A biomass gasifier is an advanced device designed to convert solid biomass materials-such as wood chips, crop residues, saw-dust, coconut shells, and other organic matter-into a combustible gas mixture known as producer gas. The conversion process, known as gasification, is a thermo-chemical process that takes place in a controlled environment with limited oxygen. Unlike complete combustion, gasification allows only partial oxidation of biomass, producing a gas rich in carbon monoxide (CO), hydrogen (H2), methane (CH4), and nitrogen (N2). This gas mixture can be used as a fuel for internal combustion engines, power generation, cooking, or industrial heating applications.
Principle of Gasification
Gasification involves a sequence of four key thermo-chemical reactions within the reactor, occurring at temperatures ranging from 800–1000°C:
1. Drying Zone: Moisture present in the biomass is evaporated due to the rising heat.
H2O (liquid) ? H2O (vapor)
2. Pyrolysis Zone: Biomass decomposes in the absence of oxygen to form volatile gases, tar, and solid char.
Biomass ? Char + Volatile gases + Tar
3. Oxidation Zone: A small amount of air or oxygen is introduced to partially combust the biomass, generating heat to sustain the process.

Biomass, a diverse and renewable resource, holds immense potential as a source of energy, feedstock, and environmental solutions. However, effectively harnessing its benefits necessitates a systematic approach. This chapter introduces the concept of Biomass Management Techniques as a pivotal framework for optimizing the utilization of biomass resources. With a focus on sustainable practices, this chapter delves into various techniques to handle, process, and utilize biomass efficiently. From collection and transportation to storage, conversion, and beyond, Biomass Management Techniques encompass a wide array of methods that ensure the seamless integration of biomass into energy generation, industrial processes, and environmental conservation.

6.1 Introduction

Biomass pellets are one of the most common types of biomass fuel. It is generally composed of wood waste, agricultural biomass, grasses, and forest residues, and is one of the most popular types of biomass fuel available today. Pelletization of biomass results in significant savings in terms of transportation, and storage, as well as the ease of handling biomass as a whole. In terms of flowability, dense cube pellets are similar to cereal grains in terms of their characteristics of being dense and cube-shaped. Due to their regular geometry and small size, biomass pellets are easily fed through an automatic feed system with fine calibration thanks to their regular shape. Because pellets are so dense, they can be stored in a compact way and transported over a long distance in a rational and efficient manner, because of their density. Furthermore, pellets can also be produced with a low moisture content, even though they are extremely dense. This allows them to burn with a high degree of combustion efficiency due to their low moisture content.

1.1 General

The term “biomass” generally refers to renewable organic matter generated by plants through photosynthesis. Materials having organic combustible matter is also referred under biomass.Biomass is an important fuel source in our overall energy scenario. Biomass is produced through chemical storage of solar energy in plants and other organic matter as a result of photosynthesis. During this process conversion of solar energy in sugar and starch, which are energy rich compounds takes place. The chemical reaction of photosynthesis can be written as:

6CO₂ + 6H₂O + sunlight → C₆H₁₂O₆ + 6O₂ + 636kcal

It indicates that the storage of 636 kcal is associated with the transfer of 72 gm carbon into organic matter. Biomass can be directly utilized as fuel or can be converted through different routes into useful forms of fuel. In fact, biomass is a source of five useful agents, which start with ‘F’ like food, fodder, fuel, fiber and fertilizer. Further, biomass has many advantages like.

(1) It is widely available

(2) Its technology for production and conversion is well understood.

(3) It is suitable for small or large applications

(4) Its production and utilisation requires only low light intensity and low temperature (5 to 35°C)

(5) It incorporates advantage of storage and transportation

(6) Comparatively, it is associated with low or negligible pollution.

1.    Introduction    232
2.    Photosynthesis and Biomass Yields    232
3.    Biomass Properties    233
    3.1.     Polymeric and chemical composition, 233
    3.2.     Fuels analysis, 235
    3.3.     Physical properties, 236

Green nanocomposites offer promising possibilities for biomedical applications because biodegradable matrices can be combined with nanoscale fillers to obtain specific functional properties. This chapter explores their applications in tissue engineering and drug delivery, with attention to materials such as chitosan, alginate, cellulose, and polylactic acid. It discusses the fundamentals of green nanocomposites, tissue-engineering applications, controlled drug delivery, toxicity, biocompatibility, regulatory considerations, and current limitations. Nanocomposite systems can provide useful mechanical, thermal, antimicrobial, antioxidant, and therapeutic characteristics while supporting more sustainable material development. The chapter highlights the importance of balancing biomedical functionality, safety, environmental responsibility, processing requirements, and long-term biological compatibility.

1. Introduction
Agro-industrial waste plays a crucial role in bioremediation, the process of usingbiological organisms to remove or neutralize pollutants from contaminatedenvironments (Garg, 2020). With the rise of industrialization and agriculturalactivities, there’s a corresponding increase in waste production. However,these waste materials, often rich in organic compounds, can be repurposedas valuable resources as mentioned in scientific studies (Sahota and Sharma,2020; Yadav et al., 2022).

1. Introduction to Biomedical Waste (BMW)
The waste produced at different medical facilities, including hospitals,laboratories, research centers, mortuaries, and autopsy centers is considered asBiomedical Waste (BMW). Some of the BMW is hazardous whereas some arenon-hazardous in nature. Hazardous waste includes, Infectious, Pathological,Microbiological, Pharmaceutical, Chemical, Cytotoxic and Radioactive wastematerial as described by World Health Organization (Fig. 1). Healthcarepersonnel and the general public are at risk from physical, chemical, andmicrobiological effects of hazardous waste. On the other hand, the nonhazardousBMW which are not harmful, include packaging material made upof plastic & thermocol, cardboards, paper waste etc. (Capoor & Parida, 2021).

1. Introduction
Since plastic was discovered, global plastic production for industrial scale usages has grown exponentially, causing a tremendous increase in plastic waste from a few tons in the 1950's to almost 400 million tons in 2018 (Syberg et al. 2021). Plastic is non-biodegradable and ubiquitous.

Environmental degradation of plastic operates through a mechanism ofphysical fragmentation, photodegradation and microbial degradation (Wright
et al., 2020), resulting in fragmentation of larger plastics into smaller plasticparticles, also called microplastics and nanoplastics (MNPs). These debris areserious environmental threats (Hartmann et al., 2019).

Abstract

Excessive use and treatment of soil with pesticides under the adage, “if little is good, a lot more will be better” has played havoc with human and other life forms and can also cause populations of beneficial soil microorganisms to decline, which indirectly affect soil fertility. Soil constitutes a major environmental sink for many pesticides. These pesticides are either taken up from soil by plants and then pass into the bodies of invertebrates, water or air, directly or indirectly and affect public health and beneficial biota of the ecosystem. Bioremediation provides very attractive, eco-friendly and economic solution to many of our hazardous pollution problems. For both economic and ecological reasons, biological degradation has become an increasingly popular alternative for treatment of hazardous wastes.