Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review

*Swapan Suman, Anand Mohan Yadav, Nomendra Tomar and Awani Bhushan*

### **Abstract**

Biomass energy is one of the alternative sources of energy, which is particularly accessible in huge quantity worldwide in rural areas. Globally, solid biomass waste is the fourth as an energy resource after coil, oil and gas, which was providing approximately 14% of the world's energy needs. The potential of biomass materials depends on feedstock quantities and their composition. The use of biomass materials as energy source provides extensive benefits as far as the environment is concerned. The agricultural biomass materials absorb carbon dioxide (CO2) during growth and emit it during combustion. Utilization of these types of wastes in various applications is in the form of a renewable and CO2-neutral fuel. The physicochemical and structural analyses of agricultural biomass differ significantly with the feedstock types. This review study provides an alternative approach and better understanding to utilize huge amount of energy stored in biomass as the substitute of fossil fuels and also it should play an important role in sustainable energy systems as a component of a renewable energy mix.

**Keywords:** biomass, combustion characteristics, physicochemical properties, renewable energy, bio-energy

### **1. Introduction**

Energy is most imperative need of human life. Energy consumption pattern indicates the social and economic development of any country [1]. Primary energy sources (natural gas, oil, coal) are considered as the main energy sources in the world [2]. **Table 1** shows the world's primary energy demand that is projected until 2035. As clearly can be seen, as the total worldwide demands for energy keep increasing year-by-year, biomass and other renewables are expected to gain significant contributions in meeting these demands. The world's depleting fossil fuels and increasing Green House Gas (GHG) emissions have given rise to much research into renewable and cleaner energy. In 2010, 76% of total GHG emissions, CO2 remain the major anthropogenic GHG with the increasing fossil CO2 emissions more than trebling from 420 GtCO2 in 1970–1300 GtCO2 in 2010 [3]. Since 2000, emissions of anthropogenic CO2 have risen by more than 3% per year with the net addition likely to rise to 8–12 GtC by 2020 and as much as 6–23 GtC by 2050 [4, 5].

The concern over global warming and climate changes has stimulated a search for alternatives of energy that are renewable and environment friendly. There

are various forms of energy sources that are abundantly available which includes nuclear, wind, solar, biomass, waste materials, geothermal, tidal, hydro, etc. The exploitation of these energy sources are growing in different parts of the world and its potential depends on various aspects such as, energy policy target, renewable energy market, technology development and topographical regions [6, 7].

Renewable energy resources that use domestic resources have the potential to provide energy services with zero emissions of both air pollutants and greenhouse gases [8]. Among the various renewable energy sources, biomass has the potential to be used as alternative source of energy with CO2 neutral [9]. Apart from this, less content of N and S as compared to the fossil fuel makes it environment friendly and does not promote acid rain or greenhouse gas emission [10]. Biomass is a potentially important source of renewable energy in agricultural countries because of abundant supply and its low prices (**Table 1**).

#### **1.1 Bio-waste sources**

Bio-waste materials includes woody crops and wastes, agricultural wastes, bagasse, waste paper, sawdust, municipal solid waste, waste from food processing, and animal or cattle wastes. These wastes are significant potential resource for electricity generation, and like crop residues have many applications, especially in developing or developed countries [11]. Bio-waste or biomass is only substitute of fossil fuels which is renewable. Bio-waste contributes greater than 6% of global non-food energy consumption, which primitive low efficiency and highly polluting combustion in poorly controlled heating and cooking fires. Bio-waste offers important advantages as a combustion feedstock due to the high volatility of the fuel and the high reactivity [11]. Bio-waste contains much less carbon and more oxygen and has a low heating value than solid fossil fuels. The burning velocity of bio-waste (pulverized) is substantially higher than that of solid fossil fuels [12].

#### **1.2 Forms of combustion and methodology**

## *1.2.1 Forms of combustion*

Combustion is categorised in different forms such as, direct combustion, evaporation combustion, decomposition combustion, surface combustion, and smouldering combustion [13]. In evaporation combustion, the sample containing


**157**

**Table 2.**

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review*

and surface combustion are the main forms of the combustion [14].

The following two methodologies are used for combustion:

The qualitative comparison is based on literature available in particular field. Combustion of different biomass materials are distinguished on the basis of the

The quantitative comparison is based on description of individually built or planned plants or industries information that suppliers and owners of biomass combustion plants have given about their efficiencies, investment costs and emissions. In quantitative comparison we prepare a model or rough information about various biomass combustion plants and further we analyse their efficiency and other

type

fuel or low grade fuel

Burner Burns wood powder and fine powder such as bagasse

Kiln furnace Used for combustion of high moisture fuel such as liquid

Restricted to fuel size on its fluidity

pith by burners, same as that for liquid fuel

Grate is level or sloping. Ignites and burns as surface combustion of biomass supplied to grate. Used in smallscale batch furnace for biomass containing little ash

Grate moves gradually and is divided into combustion zone and after-combustion zone. Due to continuous ash discharge, grate load is large. The combustion obstruction caused by ash can be avoided. Can be applied to wide range of fuels from chip type to block

Uses sand for bed material, keeps fuel and sand in furnace in boiling state with high-pressure combustion air, and burns through thermal storage and heat transmission effect of sand. Suitable for high moisture

organic sludge and food residue, or large waste etc.

The features of some combustion methods are shown in **Table 2**.

**Combustion type Features**

Horizontal/inclined grate Water-cooling grate Dumping grate

Forward moving grate Reverse moving grate

Bubbling fluidized bed

Circulation fluidized bed

Step grate Louver grate

combustion

combustion

molecular structure with comparatively low fusing temperature evaporates by heating, and reacts with oxygen in gas phase. In decomposition combustion, gases (such as H2, CO, CmHn, H2O, and CO2) produced from thermal decomposition reacts with oxygen in gas phase, and produces flame. Usually, char or say bio-char remains after these reaction (forms of combustion) and burns by surface combustion. Smouldering combustion is the thermal decomposition at temperature lower and then the ignition temperature of volatile component of the reactive biomass samples. In industrial direct combustion of biomass, decomposition combustion

*DOI: http://dx.doi.org/10.5772/intechopen.91398*

*1.2.2 Methodology*

characteristics.

**Combustion method**

Fixed bed combustion

Moving bed combustion

Fluidized bed combustion

Rotary hearth furnace combustion

*Combustion type and feature of biomass.*

Burner combustion

• Qualitative comparison and

• Quantitative comparison.

type of combustion process used.

#### **Table 1.**

*World's primary energy demands in MTOE (metric tonne of oil equivalent).*

## *Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review DOI: http://dx.doi.org/10.5772/intechopen.91398*

molecular structure with comparatively low fusing temperature evaporates by heating, and reacts with oxygen in gas phase. In decomposition combustion, gases (such as H2, CO, CmHn, H2O, and CO2) produced from thermal decomposition reacts with oxygen in gas phase, and produces flame. Usually, char or say bio-char remains after these reaction (forms of combustion) and burns by surface combustion. Smouldering combustion is the thermal decomposition at temperature lower and then the ignition temperature of volatile component of the reactive biomass samples. In industrial direct combustion of biomass, decomposition combustion and surface combustion are the main forms of the combustion [14].

## *1.2.2 Methodology*

*Renewable Energy - Technologies and Applications*

dant supply and its low prices (**Table 1**).

**1.2 Forms of combustion and methodology**

**1.1 Bio-waste sources**

*1.2.1 Forms of combustion*

are various forms of energy sources that are abundantly available which includes nuclear, wind, solar, biomass, waste materials, geothermal, tidal, hydro, etc. The exploitation of these energy sources are growing in different parts of the world and its potential depends on various aspects such as, energy policy target, renewable energy market, technology development and topographical regions [6, 7].

Renewable energy resources that use domestic resources have the potential to provide energy services with zero emissions of both air pollutants and greenhouse gases [8]. Among the various renewable energy sources, biomass has the potential to be used as alternative source of energy with CO2 neutral [9]. Apart from this, less content of N and S as compared to the fossil fuel makes it environment friendly and does not promote acid rain or greenhouse gas emission [10]. Biomass is a potentially important source of renewable energy in agricultural countries because of abun-

Bio-waste materials includes woody crops and wastes, agricultural wastes, bagasse, waste paper, sawdust, municipal solid waste, waste from food processing, and animal or cattle wastes. These wastes are significant potential resource for electricity generation, and like crop residues have many applications, especially in developing or developed countries [11]. Bio-waste or biomass is only substitute of fossil fuels which is renewable. Bio-waste contributes greater than 6% of global non-food energy consumption, which primitive low efficiency and highly polluting combustion in poorly controlled heating and cooking fires. Bio-waste offers important advantages as a combustion feedstock due to the high volatility of the fuel and the high reactivity [11]. Bio-waste contains much less carbon and more oxygen and has a low heating value than solid fossil fuels. The burning velocity of bio-waste

(pulverized) is substantially higher than that of solid fossil fuels [12].

**Primary energy Years**

*World's primary energy demands in MTOE (metric tonne of oil equivalent).*

Combustion is categorised in different forms such as, direct combustion, evaporation combustion, decomposition combustion, surface combustion, and smouldering combustion [13]. In evaporation combustion, the sample containing

Coal 3315 3892 3966 3984 3934 Oil 4059 4252 4346 4550 4662 Gas 2596 2919 3132 3550 3748 Nuclear 712 818 968 1178 1273 Hydro 276 331 376 450 476 Biomass 1225 1385 1501 1780 1957 Other renewables 89 178 268 521 699 Total 12,271 13,776 14,556 16,014 16,748

**2008 2015 2020 2030 2035**

**156**

**Table 1.**

*Source: www.eia.org.*

The following two methodologies are used for combustion:


The qualitative comparison is based on literature available in particular field. Combustion of different biomass materials are distinguished on the basis of the type of combustion process used.

The quantitative comparison is based on description of individually built or planned plants or industries information that suppliers and owners of biomass combustion plants have given about their efficiencies, investment costs and emissions. In quantitative comparison we prepare a model or rough information about various biomass combustion plants and further we analyse their efficiency and other characteristics.


The features of some combustion methods are shown in **Table 2**.

## **Table 2.**

*Combustion type and feature of biomass.*

## **1.3 Bio-waste conversion technologies**

Biomass can be converted to useful products by two main processes:

## I.Thermochemical process

II.Bio-chemical process

## *1.3.1 Thermochemical process*

Thermochemical process is one of the bioenergy conversion technologies, which are used to extract energy from the biomass. Thermo-chemical conversion process can be categorized as combustion, pyrolysis, gasification and liquefaction. These processes convert the solid waste biomass into energy rich valuable products. Selection of conversion process depends upon the feedstock type and quantity of biomass, desired form of the energy, i.e., end use requirements, environmental standards and economic conditions [15, 16]. The combustion of agricultural biomass produces (800–1600°C) heat energy for electricity generation. Gasification process generates (700–1000°C) heat energy with a combustible gas mixture, commonly known as producer gas or syngas, which can be used to make synthesize fuels or other chemicals using catalysts [17]. Pyrolysis also occurs at moderate to high temperatures (450–1000°C) in the absence of oxygen to produce energy-rich liquid known as bio-oil and solid char or sometimes biochar [18]. Liquefaction processing occurs at pressure of (5–25 MPa) to prevent boiling of water in the slurry and at temperatures ranging from 200 to 500°C, depending upon whether the desired products are fractionated plant polymers [19], a partially deoxygenated liquid product known as bio-crude [20]. Liquefaction processing at modest temperatures fractionates biomass into cellulose fibres, hemicellulose dehydration products, and lignin [19].

Thus, thermochemical processing offers opportunities for rapid processing of diverse feedstocks, including recalcitrant materials, for production of fuels, chemicals, and power.


**159**

fuel are given in **Table 4**.

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review*

Ravandranath and Hall [21] and Amigun et al. [22] reported that the biomass materials are converted to biofuels from which energy is extracted from it for suitable utilization. They found that there are at-least five different forms of biofuels which are in use nowadays. These are bioethanol, biodiesel, biogas, bio-methanol and biochar. Traditional technologies depend on mainly on its efficient systems such as open fires for cooking and space heating. Improved technologies are tried to increase in efficiency. Additional details on these technologies are given in **Table 3**.

Gumisiriza et al. [24] reported that in bio-chemical conversion processes two main processes are used, fermentation and anaerobic digestion, together with a lesser-used process based on mechanical extraction/chemical conversion.

• Fermentation is used on a large scale in various countries to produce ethanol from sugar crops and starch crops. The biomass is ground down and then the starch is converted by enzymes to sugars; after that, yeast converts the sugars

• Anaerobic digestion is the conversion of organic material directly into gas, termed biogas, a mixture of mainly methane and carbon dioxide with small quantities of other gases such as hydrogen sulphide. The biomass is converted by bacteria to produce gas with an energy content of about 20–40% of the

Combustion properties of biomass can be classified as two following properties first is macroscopic properties and second is microscopic properties [25–27]. The macroscopic properties of agricultural biomass includes ultimate analysis, heating value, moisture content, particle size analysis, bulk density, and ash fusion temperature (AFT). And microscopic analysis of agricultural biomass includes thermal analysis, chemical kinetics, and mineral data. Fuel characteristics of biomass mention above have been reported by Bushnell et al. [26]. Fuel combustion properties of biomass can be conveniently grouped into physical, chemical, thermal, and mineral properties [27]. Physical properties for combustion such as porosity, bulk density, particle size, and shape distribution are related to fuel preparation methods. Chemical properties for combustion are the ultimate and proximate analysis, gross calorific value, and heating value of the volatiles [28]. Thermal properties of combustion such as rate of combustion with burning profiles, thermal analysis (TG/DTG), and emissivity vary with moisture content, temperature, and degree of thermal degradation [29]. Thermal degradation products of biomass consist of moisture, volatiles, char and ash. The yields depend on the pyrolysis time & temperature, heating rate, feedstock type, particle size, vapour residence time, sweeping gas flow rate, atmospheric gas flow rate, and types of reactors [30]. The standard methods for analyses of biomass

Proximate analysis has long been established for assessing the quality of coal, biomass and biochar fuels through quantifying the concentrations of moisture, 'volatile matter', 'fixed C' and ash. Proximate analysis was performed on biomass waste samples for the determination of ash, moisture, volatile matter and fixed carbon contents [11]. To determine the basic elemental composition (carbon, hydrogen, nitrogen and sulphur content) of the biomass waste samples using CHNS

*DOI: http://dx.doi.org/10.5772/intechopen.91398*

*1.3.2. Bio-chemical process*

into ethanol.

lower heating value of the feedstock.

**2. Combustion properties of biomass**

## **Table 3.**

*Conversion technologies for transforming biomass into energy [22, 23].*

#### *Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review DOI: http://dx.doi.org/10.5772/intechopen.91398*

Ravandranath and Hall [21] and Amigun et al. [22] reported that the biomass materials are converted to biofuels from which energy is extracted from it for suitable utilization. They found that there are at-least five different forms of biofuels which are in use nowadays. These are bioethanol, biodiesel, biogas, bio-methanol and biochar. Traditional technologies depend on mainly on its efficient systems such as open fires for cooking and space heating. Improved technologies are tried to increase in efficiency. Additional details on these technologies are given in **Table 3**.

## *1.3.2. Bio-chemical process*

*Renewable Energy - Technologies and Applications*

**1.3 Bio-waste conversion technologies**

I.Thermochemical process

II.Bio-chemical process

*1.3.1 Thermochemical process*

chemicals, and power.

Biomass can be converted to useful products by two main processes:

Thermochemical process is one of the bioenergy conversion technologies, which are used to extract energy from the biomass. Thermo-chemical conversion process can be categorized as combustion, pyrolysis, gasification and liquefaction. These processes convert the solid waste biomass into energy rich valuable products. Selection of conversion process depends upon the feedstock type and quantity of biomass, desired form of the energy, i.e., end use requirements, environmental standards and economic conditions [15, 16]. The combustion of agricultural biomass produces (800–1600°C) heat energy for electricity generation. Gasification process generates (700–1000°C) heat energy with a combustible gas mixture, commonly known as producer gas or syngas, which can be used to make synthesize fuels or other chemicals using catalysts [17]. Pyrolysis also occurs at moderate to high temperatures (450–1000°C) in the absence of oxygen to produce energy-rich liquid known as bio-oil and solid char or sometimes biochar [18]. Liquefaction processing occurs at pressure of (5–25 MPa) to prevent boiling of water in the slurry and at temperatures ranging from 200 to 500°C, depending upon whether the desired products are fractionated plant polymers [19], a partially deoxygenated liquid product known as bio-crude [20]. Liquefaction processing at modest temperatures fractionates biomass into cellulose fibres, hemicellulose dehydration products, and lignin [19]. Thus, thermochemical processing offers opportunities for rapid processing of diverse feedstocks, including recalcitrant materials, for production of fuels,

**Technology Sub-categories of Technology Products**

• Direct combustion to produce steam

• Slow pyrolysis (carbonization)

Liquefaction • Hydro-thermal • Bio-oil

Gasification • Steam gasification • Gas, char, liquid residue

• Heat

• Char, gas • Bio-oil, char • Bio-oil

• Bio-oil

• Briquettes • Pellets

• Radiant heat, hot gas • Electrical energy

• Heat (steam), electrical energy

• Bio-oil, tar, gas, solid char

• Tar, gas, char, bio-oil

Combustion • Direct combustion to produce heat

• Co-firing • Co-generation

• Flash pyrolysis • Vacuum pyrolysis • Intermediate pyrolysis • Hydro-pyrolysis

• Pelleting

*Conversion technologies for transforming biomass into energy [22, 23].*

Pyrolysis • Fast pyrolysis

Densification • Briquetting

**158**

**Table 3.**

Gumisiriza et al. [24] reported that in bio-chemical conversion processes two main processes are used, fermentation and anaerobic digestion, together with a lesser-used process based on mechanical extraction/chemical conversion.


## **2. Combustion properties of biomass**

Combustion properties of biomass can be classified as two following properties first is macroscopic properties and second is microscopic properties [25–27]. The macroscopic properties of agricultural biomass includes ultimate analysis, heating value, moisture content, particle size analysis, bulk density, and ash fusion temperature (AFT). And microscopic analysis of agricultural biomass includes thermal analysis, chemical kinetics, and mineral data. Fuel characteristics of biomass mention above have been reported by Bushnell et al. [26]. Fuel combustion properties of biomass can be conveniently grouped into physical, chemical, thermal, and mineral properties [27].

Physical properties for combustion such as porosity, bulk density, particle size, and shape distribution are related to fuel preparation methods. Chemical properties for combustion are the ultimate and proximate analysis, gross calorific value, and heating value of the volatiles [28]. Thermal properties of combustion such as rate of combustion with burning profiles, thermal analysis (TG/DTG), and emissivity vary with moisture content, temperature, and degree of thermal degradation [29]. Thermal degradation products of biomass consist of moisture, volatiles, char and ash. The yields depend on the pyrolysis time & temperature, heating rate, feedstock type, particle size, vapour residence time, sweeping gas flow rate, atmospheric gas flow rate, and types of reactors [30]. The standard methods for analyses of biomass fuel are given in **Table 4**.

Proximate analysis has long been established for assessing the quality of coal, biomass and biochar fuels through quantifying the concentrations of moisture, 'volatile matter', 'fixed C' and ash. Proximate analysis was performed on biomass waste samples for the determination of ash, moisture, volatile matter and fixed carbon contents [11]. To determine the basic elemental composition (carbon, hydrogen, nitrogen and sulphur content) of the biomass waste samples using CHNS


#### **Table 4.**

*Standard methods of biomass fuel [11].*

analyser. Oxygen content was calculated by the difference. The gross calorific value (GCV) of all studied agricultural biomass samples was determined by bomb calorific measurement.

Ash or inorganic materials in agricultural biomass depend on the type of the feedstocks and the soil contamination in which the plant grows. Ash content is an important parameter directly affecting the heating value. High ash content of a plant part makes it less desirable as fuel [31, 32]. The composition of mineral matter can vary between and within each biomass sample. The higher GCV of WC, WD and CS are owing to lower content of incombustible mineral matter (ash) and higher amount of combustible components (VM, FC, C and H) [33].

The components of biomass include cellulose, hemicelluloses, lignin, lipids, proteins, simple sugars, starches, water, and other compounds [29]. The concentration of each class of compounds varies depending on different feedstocks. Due to the carbohydrate structure, biomass is highly oxygenated with respect to conventional fossil fuels including HC liquids and coals. Typically, 30–40 wt.% of the dry matter in biomass is oxygen [30]. The lignin value in case of woody and coconut shell biomass is higher than herbaceous and agricultural biomass [34]. Heating value, which is a very important factor affecting utilization of any biomass material as a fuel, is affected by the proportion of combustible organic components (called as extractives) present in it. The heating values of the extractive-free were found to be lower than those of the extracted parts, which indicate a likely positive contribution of extractives towards the increase of heating values [29]. Lignin has higher energy content (about 30%) than cellulose and hemicellulose, because of its higher degree of oxidation [35].

As we know that some of agricultural biomasses have high contents of alkali oxides and salts, the low melting points of which may lead to various problems during combustion [36, 37]. These agricultural residues include husks, straws, stalks etc. produced after harvesting the crop. As the crop residues are normally cultivated with the aid of chemical fertilizers, these residues generally contain higher amounts of sodium/potassium compounds presents in their ash. Higher concentration of these alkali compounds result in problems like bed agglomeration, slagging on furnace walls/super heater tubes and fouling of heat transfer surfaces [38]. The successful design and operation of a fluidized bed combustor depends on the ability to control and mitigate these ash related problems [39].

**161**

**Table 5.**

*Source: Refs. [11, 30].*

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review*

The use of agricultural biomass as a fuel provides significant benefits in various fields as energy source as far as the environment is concerned [40]. Agricultural biomass absorbs carbon dioxide (CO2) during growth, and emits it during combustion. Therefore, it helps the atmospheric carbon dioxide (CO2) recycling but, it does not contribute in the greenhouse gas (GHG) effect [41]. Agricultural biomass differs from coal in many important aspects, such as the physical and chemical properties. Biomass has less carbon, more oxygen, more silica and potassium, less aluminium and iron, lower heating value, higher moisture content, and lower density and friability than coal. At low temperatures biomass materials would be instantly ignited, when they are feed in to the high temperature furnace. Here, the pivotal factor is the moisture content is low in most biomass materials, and also can be high for some biomass materials, e.g., bagasse. Basically in the all biomass materials found the high VM contents [42]. The volatiles comprise mainly of the combustibles like as CO, H2 and C*x*Hy. These aspects show that the combustion of the volatiles would be the dominant

Kaeferstein et al. [43] state that during the batch experiments in combustion process of biomass in a bubbling fluidized bed using oxygen concentration profiles measured directly over the bed with solid electrolyte sensor. During the combustion process, he observed that there was a rapid ingestion of oxygen, which took place in one phase. Whereas, for coal, the oxygen ingestion profile exhibited in two phases; a short phase for volatile combustion and a long phase for char combustion. The combustion process of biomass was almost complete after the complete combustion of volatiles. Heat distribution analysis during the combustion of biomass showed that over 67% of their

If we talking about designing a combustor for the precise use of agricultural biomass waste, we consider the suitable parameters likes, the variability of moisture, the volatile matter content, ash content, ash composition, and the energy content of the fuel [45, 46]. Accordingly follow above statement the requirements for designing a combustor such as low moisture content (about 3–9%) and high volatile matter (about 60–80%) for high burning rate reactivity, low ash content (about

**Sl. no. Property Biomass samples Coal** 1. M content (wt% of dry fuel) 1–10 2–2.5 2. Ash content (wt% of dry fuel) 0.5–22 15–18 3. C content (wt% of dry fuel) 30–50 70–75 4. O content (wt% of dry fuel) 30–60 5–15 5. S content (wt% of dry fuel) <0.5 0.5–0.9 6. SiO2 content (wt% of dry ash) 3.78–78.20 8–15 7. K2O content (wt% of dry ash) 5.34–24.70 0.2–1.0 8. Al2O3 content (wt% of dry ash) 0.71–11.69 4–6 9. Fe2O3 content (wt% of dry ash) 0.14–16.69 0.01–2.0 10. Ignition temperature (°C) 155–250 490–595 11 Peak temperature (°C) 250–320 — 12. Heating value (MJ/kg) 14–20 23–28

calorific values were released through the combustion of the volatiles [44].

*Comparison on physical, chemical and combustion properties of biomass materials and coal.*

*DOI: http://dx.doi.org/10.5772/intechopen.91398*

step during the combustion process.

**3. Combustion study for biomass materials**

## **3. Combustion study for biomass materials**

*Renewable Energy - Technologies and Applications*

**Property Standard methods**

Volatile matter ASTM E 872, ASTM E 897

Moisture ASTM E871

Fixed carbon By difference

Carbon, hydrogen ASTM E 777 Nitrogen ASTM E 778 Sulphur ASTM E 775 Oxygen By difference Heating value (gross calorific value) ASTM D 2015, E 711

Ash ASTM D1102 (873 K), ASTM E830 (848 K)

calorific measurement.

*Standard methods of biomass fuel [11].*

**Table 4.**

*Proximate analysis*

*Ultimate analysis*

analyser. Oxygen content was calculated by the difference. The gross calorific value (GCV) of all studied agricultural biomass samples was determined by bomb

Ash elemental ASTM D3682, ASTM D2795, ASTM D4278, AOAC 14.7

higher amount of combustible components (VM, FC, C and H) [33].

cellulose and hemicellulose, because of its higher degree of oxidation [35].

to control and mitigate these ash related problems [39].

As we know that some of agricultural biomasses have high contents of alkali oxides and salts, the low melting points of which may lead to various problems during combustion [36, 37]. These agricultural residues include husks, straws, stalks etc. produced after harvesting the crop. As the crop residues are normally cultivated with the aid of chemical fertilizers, these residues generally contain higher amounts of sodium/potassium compounds presents in their ash. Higher concentration of these alkali compounds result in problems like bed agglomeration, slagging on furnace walls/super heater tubes and fouling of heat transfer surfaces [38]. The successful design and operation of a fluidized bed combustor depends on the ability

Ash or inorganic materials in agricultural biomass depend on the type of the feedstocks and the soil contamination in which the plant grows. Ash content is an important parameter directly affecting the heating value. High ash content of a plant part makes it less desirable as fuel [31, 32]. The composition of mineral matter can vary between and within each biomass sample. The higher GCV of WC, WD and CS are owing to lower content of incombustible mineral matter (ash) and

The components of biomass include cellulose, hemicelluloses, lignin, lipids, proteins, simple sugars, starches, water, and other compounds [29]. The concentration of each class of compounds varies depending on different feedstocks. Due to the carbohydrate structure, biomass is highly oxygenated with respect to conventional fossil fuels including HC liquids and coals. Typically, 30–40 wt.% of the dry matter in biomass is oxygen [30]. The lignin value in case of woody and coconut shell biomass is higher than herbaceous and agricultural biomass [34]. Heating value, which is a very important factor affecting utilization of any biomass material as a fuel, is affected by the proportion of combustible organic components (called as extractives) present in it. The heating values of the extractive-free were found to be lower than those of the extracted parts, which indicate a likely positive contribution of extractives towards the increase of heating values [29]. Lignin has higher energy content (about 30%) than

**160**

The use of agricultural biomass as a fuel provides significant benefits in various fields as energy source as far as the environment is concerned [40]. Agricultural biomass absorbs carbon dioxide (CO2) during growth, and emits it during combustion. Therefore, it helps the atmospheric carbon dioxide (CO2) recycling but, it does not contribute in the greenhouse gas (GHG) effect [41]. Agricultural biomass differs from coal in many important aspects, such as the physical and chemical properties. Biomass has less carbon, more oxygen, more silica and potassium, less aluminium and iron, lower heating value, higher moisture content, and lower density and friability than coal.

At low temperatures biomass materials would be instantly ignited, when they are feed in to the high temperature furnace. Here, the pivotal factor is the moisture content is low in most biomass materials, and also can be high for some biomass materials, e.g., bagasse. Basically in the all biomass materials found the high VM contents [42]. The volatiles comprise mainly of the combustibles like as CO, H2 and C*x*Hy. These aspects show that the combustion of the volatiles would be the dominant step during the combustion process.

Kaeferstein et al. [43] state that during the batch experiments in combustion process of biomass in a bubbling fluidized bed using oxygen concentration profiles measured directly over the bed with solid electrolyte sensor. During the combustion process, he observed that there was a rapid ingestion of oxygen, which took place in one phase. Whereas, for coal, the oxygen ingestion profile exhibited in two phases; a short phase for volatile combustion and a long phase for char combustion. The combustion process of biomass was almost complete after the complete combustion of volatiles. Heat distribution analysis during the combustion of biomass showed that over 67% of their calorific values were released through the combustion of the volatiles [44].

If we talking about designing a combustor for the precise use of agricultural biomass waste, we consider the suitable parameters likes, the variability of moisture, the volatile matter content, ash content, ash composition, and the energy content of the fuel [45, 46]. Accordingly follow above statement the requirements for designing a combustor such as low moisture content (about 3–9%) and high volatile matter (about 60–80%) for high burning rate reactivity, low ash content (about


#### **Table 5.** *Comparison on physical, chemical and combustion properties of biomass materials and coal.*

0.5–6%, except rice and husk materials) for less in erosion, corrosion and ash fouling problems [45]. Due to high volatile matter of studied agricultural biomass materials, they have well in heating energy.

**Table 5** shows the physical, chemical and combustion properties of biomass, coal and studied biomass samples. Biomass has significantly lower heating values than most of the coals. This may be caused, due to higher moisture and oxygen content. It was also to be seen that the lower heating values lead to lower burning temperatures. Agricultural biomass also has higher volatile matter [47] than coals. Agricultural biomass usually consists of 70–80% VM whereas coal consists of 10–50% VM [48].

## **4. Conclusions**

From above discussion, it can be concluded that the high volatile matter contents of agricultural biomass have a significant effect on the combustion mechanisms. The volatiles consist mainly of combustibles and a significant amount of energy is released during their combustion. Biomass samples have ash content less than 5%, which is much less than any other fossil fuel used for combustion processes. Range obtained for VM content i.e., 60–85% in studied biomass is as high as any of the fossil fuels [49, 50], which can initiate ignition even at lower temperature (150–250°C) and support combustion processes, whereas in other fossil fuels like coal for initiating any combustion process the required ignition temperature ranges 260–450°C. Biomass also have less in nitrogen and sulphur content than any other fossil fuels (coal), which indicates less evaluation of NOx and SOx during combustion processes [48]. These above characteristics of biomass are importance with respect to the design and operation of combustion systems for agricultural biomass. The combustion significances of the biomass composition, particularly the fuel volatility, involve changing the process of combustion [51].

An attempt has also being made in this chapter to overview and understanding the different characteristics and properties of biomass samples and to evaluate their effect on the combustion characteristics.

## **Author details**

Swapan Suman1 \*, Anand Mohan Yadav2 , Nomendra Tomar1 and Awani Bhushan1

1 Department of Mechanical Engineering, Meerut Institute of Engineering and Technology, Meerut, Uttar Pradesh, India

2 Department of Chemical Engineering, Meerut Institute of Engineering and Technology, Meerut, Uttar Pradesh, India

\*Address all correspondence to: er.ssuman@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**163**

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review*

[8] Demirbas A. Potential applications of renewable energy sources, biomass combustion problems in boiler power systems and combustion related environmental issues. Progress in Energy and Combustion Science.

[9] Gonzalez JF, Garcia CMG, Ramiro A, Gonzalez J, Sabio E, Ganan J, et al. Combustion optimisation of biomass residue pellets for domestic heating with a mural boiler. Biomass and Bioenergy.

[10] Energy for cooking in developing countries. In: World Energy Outlook. Int Energy Agency (IEA); 2006. pp. 419- 445. Available from: https://www.iea. org/publications/freepublications/ publication/cooking.pdf [Accessed: 23

[11] Demirbas A. Combustion characteristics of different biomass fuels. Progress in Energy and

[12] Marks J. Wood powder: An upgraded wood fuel. Forest Products

Journal. 1992;**42**:52-56

Combustion Science. 2004;**30**:219-230

[13] Fujii S. Baiomasu Enerugino Riyo, Kenchiku, Toshi Enerugi Sisutemuno Shingijutsu. Kuuki Chowa Eisei Kogakkai Ed; 2007. pp. 212-218 [in Japanese]

[14] Mizutani Y. Nensho Kogaku. 3rd ed. Morikita Shuppan; 2002. pp. 169-181 [in

[15] McKendry P. Energy production from biomass (part 1): Overview of biomass. Bioresource Technology.

[16] Goyal HB, Seal D, Saxena RC. Biofuels from thermochemical conversion of renewable resources: A review. Renewable and Sustainable Energy

2005;**31**:171-192

2004;**27**(2):145-154

May 2016]

Japanese]

2002;**83**(1):37-46

Reviews. 2008;**12**:504-517

*DOI: http://dx.doi.org/10.5772/intechopen.91398*

Assessment of biomass energy resources and related technologies practice in Bangladesh. Renewable and Sustainable Energy Reviews. 2014;**39**:444-460

[1] Halder PK, Paul N, Beg MRA.

[2] Yin CY. Prediction of higher heating values of biomass from proximate and ultimate analyses. Fuel.

[3] IPCC. Climate change assessments Review of the processes and procedures of the IPCC. The Netherland: Inter Academy Council; 2014. Available from: https://www.ipcc.ch/pdf/IAC\_report/

[4] IPCC. Special report on carbon dioxide capture and storage. In: Metz B, Davidson O, de Coninck HC, Loos M, Meyer LJ, editors. Prepared by Working Group III of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom/New York, NY, USA: Cambridge University Press; 2005. p. 442

[5] IEA. IEA Technology Essentialsbiofuel Production. International Energy Agency; 2007. pp. 1-4. Available from: http://www.iea.org/techno/

[6] REN21. Renewables Global Status Report: 2009 Update. Deutsche Gesellschaft für Technische

Zusammenarbeit (GTZ) GmbH; 2009. Available from: http://www.ren21.net

[7] Energy Information Administration. The Annual Energy Outlook 2009 (AEO2009), Prepared by the Energy Information Administration (EIA), Presents Long-term Projections of Energy Supply, Demand, and Prices Through 2030, Based on Results from EIA's National Energy Modeling System (NEMS). EIA Published an "Early Release" Version of the AEO2009 Reference Case in December 2008. 2009

2011;**90**:1128-1132

IAC%20Report.pdf

essentials2.pdf

**References**

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review DOI: http://dx.doi.org/10.5772/intechopen.91398*

## **References**

*Renewable Energy - Technologies and Applications*

materials, they have well in heating energy.

0.5–6%, except rice and husk materials) for less in erosion, corrosion and ash fouling problems [45]. Due to high volatile matter of studied agricultural biomass

**Table 5** shows the physical, chemical and combustion properties of biomass, coal and studied biomass samples. Biomass has significantly lower heating values than most of the coals. This may be caused, due to higher moisture and oxygen content. It was also to be seen that the lower heating values lead to lower burning temperatures. Agricultural biomass also has higher volatile matter [47] than coals. Agricultural biomass usually consists of 70–80% VM whereas coal consists of 10–50% VM [48].

From above discussion, it can be concluded that the high volatile matter contents of agricultural biomass have a significant effect on the combustion mechanisms. The volatiles consist mainly of combustibles and a significant amount of energy is released during their combustion. Biomass samples have ash content less than 5%, which is much less than any other fossil fuel used for combustion processes. Range obtained for VM content i.e., 60–85% in studied biomass is as high as any of the fossil fuels [49, 50], which can initiate ignition even at lower temperature (150–250°C) and support combustion processes, whereas in other fossil fuels like coal for initiating any combustion process the required ignition temperature ranges 260–450°C. Biomass also have less in nitrogen and sulphur content than any other fossil fuels (coal), which indicates less evaluation of NOx and SOx during combustion processes [48]. These above characteristics of biomass are importance with respect to the design and operation of combustion systems for agricultural biomass. The combustion significances of the biomass composition, particularly the fuel

**162**

**Author details**

**4. Conclusions**

Swapan Suman1

\*, Anand Mohan Yadav2

volatility, involve changing the process of combustion [51].

\*Address all correspondence to: er.ssuman@gmail.com

Technology, Meerut, Uttar Pradesh, India

effect on the combustion characteristics.

Technology, Meerut, Uttar Pradesh, India

provided the original work is properly cited.

, Nomendra Tomar1

1 Department of Mechanical Engineering, Meerut Institute of Engineering and

An attempt has also being made in this chapter to overview and understanding the different characteristics and properties of biomass samples and to evaluate their

2 Department of Chemical Engineering, Meerut Institute of Engineering and

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

and Awani Bhushan1

[1] Halder PK, Paul N, Beg MRA. Assessment of biomass energy resources and related technologies practice in Bangladesh. Renewable and Sustainable Energy Reviews. 2014;**39**:444-460

[2] Yin CY. Prediction of higher heating values of biomass from proximate and ultimate analyses. Fuel. 2011;**90**:1128-1132

[3] IPCC. Climate change assessments Review of the processes and procedures of the IPCC. The Netherland: Inter Academy Council; 2014. Available from: https://www.ipcc.ch/pdf/IAC\_report/ IAC%20Report.pdf

[4] IPCC. Special report on carbon dioxide capture and storage. In: Metz B, Davidson O, de Coninck HC, Loos M, Meyer LJ, editors. Prepared by Working Group III of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom/New York, NY, USA: Cambridge University Press; 2005. p. 442

[5] IEA. IEA Technology Essentialsbiofuel Production. International Energy Agency; 2007. pp. 1-4. Available from: http://www.iea.org/techno/ essentials2.pdf

[6] REN21. Renewables Global Status Report: 2009 Update. Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH; 2009. Available from: http://www.ren21.net

[7] Energy Information Administration. The Annual Energy Outlook 2009 (AEO2009), Prepared by the Energy Information Administration (EIA), Presents Long-term Projections of Energy Supply, Demand, and Prices Through 2030, Based on Results from EIA's National Energy Modeling System (NEMS). EIA Published an "Early Release" Version of the AEO2009 Reference Case in December 2008. 2009 [8] Demirbas A. Potential applications of renewable energy sources, biomass combustion problems in boiler power systems and combustion related environmental issues. Progress in Energy and Combustion Science. 2005;**31**:171-192

[9] Gonzalez JF, Garcia CMG, Ramiro A, Gonzalez J, Sabio E, Ganan J, et al. Combustion optimisation of biomass residue pellets for domestic heating with a mural boiler. Biomass and Bioenergy. 2004;**27**(2):145-154

[10] Energy for cooking in developing countries. In: World Energy Outlook. Int Energy Agency (IEA); 2006. pp. 419- 445. Available from: https://www.iea. org/publications/freepublications/ publication/cooking.pdf [Accessed: 23 May 2016]

[11] Demirbas A. Combustion characteristics of different biomass fuels. Progress in Energy and Combustion Science. 2004;**30**:219-230

[12] Marks J. Wood powder: An upgraded wood fuel. Forest Products Journal. 1992;**42**:52-56

[13] Fujii S. Baiomasu Enerugino Riyo, Kenchiku, Toshi Enerugi Sisutemuno Shingijutsu. Kuuki Chowa Eisei Kogakkai Ed; 2007. pp. 212-218 [in Japanese]

[14] Mizutani Y. Nensho Kogaku. 3rd ed. Morikita Shuppan; 2002. pp. 169-181 [in Japanese]

[15] McKendry P. Energy production from biomass (part 1): Overview of biomass. Bioresource Technology. 2002;**83**(1):37-46

[16] Goyal HB, Seal D, Saxena RC. Biofuels from thermochemical conversion of renewable resources: A review. Renewable and Sustainable Energy Reviews. 2008;**12**:504-517

[17] Brown RC. Biomass refineries based on hybrid thermochemical/ biological processing—An overview. In: Kamm B, Gruber PR, Kamm M, editors. Biorefineries, Biobased Industrial Processes and Products. Weinheim: Wiley-VCH Verlag GmbH; 2005

[18] Bridgwater AV, Peacocke GVC. Fast pyrolysis processes for biomass. Renewable and Sustainable Energy Reviews. 2000;**4**:1-73

[19] Allen SG, Kam LC, Zemann AJ, Antal MJ Jr. Fractionation of sugar cane with hot, compressed, liquid water. Industrial & Engineering Chemistry Research. 1996;**35**:2709-2715

[20] Elliott DC, Beckman D, Bridgwater AV. Developments in direct thermochemical liquefaction of biomass: 1983-1990. Energy and Fuels. 1991;**5**(3):399-410

[21] Ravandranath NH, Hall DO. Biomass, Energy and Environment—A Developing Country Perspective from India. New York, USA: Oxford University Press; 1995

[22] Amigun B, Musango JT, Stafford W. Biofuels and sustainability in Africa. Renewable and Sustainable Energy Reviews. 2011;**15**:1360-1372

[23] National Association of Forest Industries (NAFI). Report 4 Converting Wood Waste into Renewable Energy: A Summary of Biomass Energy Conversion Technologies. Australia: Forest and Wood Products Research and Development Corporation; 2005

[24] Gumisiriza R, Hawumba JF, Okure M, Hensel O. Biomass waste-to-energy valorisation technologies: A review case for banana processing in Uganda. Biotechnology for Biofuels. 2017;**10**:11

[25] Demirbas A. Mechanism of liquefaction and pyrolysis reactions of biomass. Energy Conversion and Management. 2000;**41**:633-646

[26] Bushnell DJ, Haluzok C, Nikoo AD. Biomass Fuel Characterization Testing and Evaluating the Combustion Characteristics of Selected Biomass Fuels. Corvallis, OR: Bonneville Power Administration; 1989

[27] Ragland KW, Aerts DJ, Baker AJ. Properties of wood for combustion analysis. Bioresource Technology. 1991;**37**:161-168

[28] Yılmaz S, Selim H. A review on the methods for biomass to energy conversion systems design. Renewable and Sustainable Energy Reviews. 2013;**25**:420-430

[29] Gasparovic L, Korenova Z, Jelemensky L. Kinetic study of wood chips decomposition by TGA. Chemical Papers. 2010;**64**(2):174-181. DOI: 10.2478/s11696-009-0109-4

[30] Jones JL, Radding SB, Takaoka S, Buekens AG, Hiraoka M, Overend R. Thermal conversion of solid wastes and biomass. In: Symposium Series 130. Washington, DC: American Chemical Society; 1980. pp. 209-603

[31] Demirbaş A. Relationships between heating value and lignin, moisture, ash and extractive contents of biomass fuels. Energy Exploration and Exploitation. 2002;**20**:105-111

[32] Vassilev SV, Baxter D, Vassileva CG. An overview of the behaviour of biomass during combustion: Part I. Phasemineral transformations of organic and inorganic matter. Fuel. 2013;**112**:391-449

[33] Chiang K-Y, Chien K-L, Lu C-H. Characterization and comparison of biomass produced from various sources: Suggestions for selection of pretreatment technologies in biomass-to-energy. Applied Energy. 2012;**100**:164-171

[34] Vassilev SV, Baxter D, Andersen LK, Vassileva CG. An overview of the chemical composition of biomass. Fuel. 2010;**89**:913-933

**165**

215-225

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review*

materials. Energy Conversion and Management. 2003;**44**:155-162

[43] Kaferstein P, Gohla M, Tepper H, Reimer H. Fluidization: Combustion and emission behaviour of biomass in fluidized bed combustion units. In: Preto FDS, editor. Proceedings of the 14th International Conference on Fluidized Bed Combustion. Vancouver, Canada, New York: ASME; 1997.

[44] Hellwig G. Basic of the combustion

[45] Jenkins BM, Baxter LL, Miles TR Jr, Miles TR. Combustion properties of biomass. Fuel Processing Technology.

[46] Tian J et al. A biomass combustion chamber: Design, evaluation, and a case study of wheat straw combustion emission tests. Aerosol and Air Quality

Research. 2015;**15**:2104-2114

Effects. 2017;**39**(9):933-940

10.5772/intechopen.73833

[47] Suman S, Gautam S. Effect of pyrolysis time and temperature on the characterization of biochars derived from biomass. Energy Sources Part A: Recovery, Utilization, and Environmental

[48] Suman S, Gautam S. Biochar Derived from Agricultural Waste Biomass Act as a Clean and Alternative Energy Source of Fossil Fuel. Energy System and Environment. Rijeka: InTechOpen; 2018. pp. 207-220. DOI:

[49] Suman S, Gautam S. Pyrolysis of coconut husk biomass: Analysis of its biochar properties. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2017;**39**(8):761-767. DOI: 10.1080/15567036.2016.1263252

of wood and straw. In: Palz W, Coombs J, Hall DO, editors. Energy from Biomass: 3rd E.C. Conference. London, UK: Elsevier Applied Science;

pp. 15-27

1985. pp. 793-798

1998;**54**:17-46

*DOI: http://dx.doi.org/10.5772/intechopen.91398*

[35] Demirbas A. Relationships between lignin contents and fixed carbons of biomass samples. Energy Conversion and Management. 2003;**44**:1481-1486

[36] Vassilev SV, Baxter D, Vassileva CG. An overview of the behaviour of

biomass during combustion: Part II. Ash fusion and ash formation mechanisms of biomass types. Fuel. 2014;**117**:152-183

[37] Reid JS, Koppmann R, Eck TF, Eleuterio DP. A review of biomass burning emissions part II: Intensive physical properties of biomass burning particles. Atmospheric Chemistry and

Physics. 2005;**5**:799-825

[38] Bapat DW, Kulkarni SV,

Bhandarkar VP. Design and operating experience on fluidized bed boiler burning biomass fuels with high alkali ash. In: Preto FDS, editor. Proceedings of the 14th International Conference on Fluidized Bed Combustion. Vancouver, New York, NY: ASME; 1997. pp. 165-174

[39] Zhang FS, Yamasaki S, Nanzyo M. Waste ashes for use in agricultural production: I. Liming effect, contents of plant nutrients and chemical characteristics of some metals. Science of the Total Environment. 2002;**284**:

[40] Southern Centre for Energy Environment. Implementation of renewable energy technologies opportunities and Barriers: Zimbabwe Country Study. Denmark: UNEP Collaborating Centreon Energy and

[41] Gadde B, Bonnet S, Menke C, Garivait S. Air pollutant emissions from rice straw open field burning

Philippines. Environmental Pollution.

characteristics of different biomass

in India, Thailand and the

[42] Acma HH. Combustion

Environment; 2001

2009;**157**:1554-1558

*Combustion Characteristics and Behaviour of Agricultural Biomass: A Short Review DOI: http://dx.doi.org/10.5772/intechopen.91398*

[35] Demirbas A. Relationships between lignin contents and fixed carbons of biomass samples. Energy Conversion and Management. 2003;**44**:1481-1486

*Renewable Energy - Technologies and Applications*

[26] Bushnell DJ, Haluzok C, Nikoo AD. Biomass Fuel Characterization Testing and Evaluating the Combustion Characteristics of Selected Biomass Fuels. Corvallis, OR: Bonneville Power

[27] Ragland KW, Aerts DJ, Baker AJ. Properties of wood for combustion analysis. Bioresource Technology.

[28] Yılmaz S, Selim H. A review on the methods for biomass to energy conversion systems design. Renewable and Sustainable Energy Reviews.

[29] Gasparovic L, Korenova Z, Jelemensky L. Kinetic study of wood chips decomposition by TGA. Chemical Papers. 2010;**64**(2):174-181. DOI: 10.2478/s11696-009-0109-4

[30] Jones JL, Radding SB, Takaoka S, Buekens AG, Hiraoka M, Overend R. Thermal conversion of solid wastes and biomass. In: Symposium Series 130. Washington, DC: American Chemical

[31] Demirbaş A. Relationships between heating value and lignin, moisture, ash and extractive contents of biomass fuels. Energy Exploration and Exploitation.

[32] Vassilev SV, Baxter D, Vassileva CG. An overview of the behaviour of biomass

during combustion: Part I. Phasemineral transformations of organic and inorganic matter. Fuel. 2013;**112**:391-449

[33] Chiang K-Y, Chien K-L, Lu C-H. Characterization and comparison of biomass produced from various sources: Suggestions for selection of pretreatment technologies in biomass-to-energy. Applied Energy. 2012;**100**:164-171

[34] Vassilev SV, Baxter D, Andersen LK, Vassileva CG. An overview of the chemical composition of biomass. Fuel.

Society; 1980. pp. 209-603

2002;**20**:105-111

2010;**89**:913-933

Administration; 1989

1991;**37**:161-168

2013;**25**:420-430

[18] Bridgwater AV, Peacocke GVC. Fast

pyrolysis processes for biomass. Renewable and Sustainable Energy

[19] Allen SG, Kam LC, Zemann AJ, Antal MJ Jr. Fractionation of sugar cane with hot, compressed, liquid water. Industrial & Engineering Chemistry

Bridgwater AV. Developments in direct thermochemical liquefaction of biomass: 1983-1990. Energy and Fuels.

Research. 1996;**35**:2709-2715

[20] Elliott DC, Beckman D,

[21] Ravandranath NH, Hall DO. Biomass, Energy and Environment—A Developing Country Perspective from India. New York, USA: Oxford

1991;**5**(3):399-410

University Press; 1995

[22] Amigun B, Musango JT,

Stafford W. Biofuels and sustainability in Africa. Renewable and Sustainable Energy Reviews. 2011;**15**:1360-1372

[23] National Association of Forest Industries (NAFI). Report 4 Converting Wood Waste into Renewable Energy: A Summary of Biomass Energy Conversion Technologies. Australia: Forest and Wood Products Research and

Development Corporation; 2005

[25] Demirbas A. Mechanism of liquefaction and pyrolysis reactions of biomass. Energy Conversion and Management. 2000;**41**:633-646

[24] Gumisiriza R, Hawumba JF, Okure M, Hensel O. Biomass waste-to-energy valorisation technologies: A review case for banana processing in Uganda. Biotechnology for Biofuels. 2017;**10**:11

Reviews. 2000;**4**:1-73

[17] Brown RC. Biomass refineries based on hybrid thermochemical/ biological processing—An overview. In: Kamm B, Gruber PR, Kamm M, editors. Biorefineries, Biobased Industrial Processes and Products. Weinheim: Wiley-VCH Verlag GmbH; 2005

**164**

[36] Vassilev SV, Baxter D, Vassileva CG. An overview of the behaviour of biomass during combustion: Part II. Ash fusion and ash formation mechanisms of biomass types. Fuel. 2014;**117**:152-183

[37] Reid JS, Koppmann R, Eck TF, Eleuterio DP. A review of biomass burning emissions part II: Intensive physical properties of biomass burning particles. Atmospheric Chemistry and Physics. 2005;**5**:799-825

[38] Bapat DW, Kulkarni SV, Bhandarkar VP. Design and operating experience on fluidized bed boiler burning biomass fuels with high alkali ash. In: Preto FDS, editor. Proceedings of the 14th International Conference on Fluidized Bed Combustion. Vancouver, New York, NY: ASME; 1997. pp. 165-174

[39] Zhang FS, Yamasaki S, Nanzyo M. Waste ashes for use in agricultural production: I. Liming effect, contents of plant nutrients and chemical characteristics of some metals. Science of the Total Environment. 2002;**284**: 215-225

[40] Southern Centre for Energy Environment. Implementation of renewable energy technologies opportunities and Barriers: Zimbabwe Country Study. Denmark: UNEP Collaborating Centreon Energy and Environment; 2001

[41] Gadde B, Bonnet S, Menke C, Garivait S. Air pollutant emissions from rice straw open field burning in India, Thailand and the Philippines. Environmental Pollution. 2009;**157**:1554-1558

[42] Acma HH. Combustion characteristics of different biomass materials. Energy Conversion and Management. 2003;**44**:155-162

[43] Kaferstein P, Gohla M, Tepper H, Reimer H. Fluidization: Combustion and emission behaviour of biomass in fluidized bed combustion units. In: Preto FDS, editor. Proceedings of the 14th International Conference on Fluidized Bed Combustion. Vancouver, Canada, New York: ASME; 1997. pp. 15-27

[44] Hellwig G. Basic of the combustion of wood and straw. In: Palz W, Coombs J, Hall DO, editors. Energy from Biomass: 3rd E.C. Conference. London, UK: Elsevier Applied Science; 1985. pp. 793-798

[45] Jenkins BM, Baxter LL, Miles TR Jr, Miles TR. Combustion properties of biomass. Fuel Processing Technology. 1998;**54**:17-46

[46] Tian J et al. A biomass combustion chamber: Design, evaluation, and a case study of wheat straw combustion emission tests. Aerosol and Air Quality Research. 2015;**15**:2104-2114

[47] Suman S, Gautam S. Effect of pyrolysis time and temperature on the characterization of biochars derived from biomass. Energy Sources Part A: Recovery, Utilization, and Environmental Effects. 2017;**39**(9):933-940

[48] Suman S, Gautam S. Biochar Derived from Agricultural Waste Biomass Act as a Clean and Alternative Energy Source of Fossil Fuel. Energy System and Environment. Rijeka: InTechOpen; 2018. pp. 207-220. DOI: 10.5772/intechopen.73833

[49] Suman S, Gautam S. Pyrolysis of coconut husk biomass: Analysis of its biochar properties. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2017;**39**(8):761-767. DOI: 10.1080/15567036.2016.1263252

*Renewable Energy - Technologies and Applications*

[50] Vassilev SV, Vassileva CG, Vassilev VS. Advantages and disadvantages of composition and properties of biomass in comparison with coal: An overview. Fuel. 2015;**158**:330-350

[51] Hroncova E, Ladomersky J, Valicek J, Dzurenda L. Combustion of Biomass Fuel and Residues: Emissions Production Perspective. Developments in Combustion Technology. Rijeka: InTechOpen; 2016. DOI: 10.5772/63793

**167**

**Chapter 11**

**Abstract**

prospects.

**1. Introduction**

Potential of Microalgal Biodiesel:

*Ashokkumar Veeramuthu and Chawalit Ngamcharussrivichai*

In the present scenario, rapid industrialization and urbanization have led to a dramatic increase in the levels of various hazardous pollutants in the environment, and this creates a serious threat to humankind. Today, most of the energy production comes from fossil fuel combustion, which is the key source of CO2 emissions. Research studies show that the utilization of microalgae could be the best option for the production of renewable and sustainable energy and for the mitigation of CO2 emission. Production of biofuels from microalgae can be classified as solid (biochar), liquid (bioethanol, biodiesel, bio-kerosene), and gaseous (biogas, bio-syngas, biohydrogen) fuels. Among these biofuels, biodiesel garners a lot of interest and attention because of its high accumulation of lipids (20–75%), which could be a potential alternative fuel for diesel engines. Algal lipids usually have a higher viscosity than petro-diesel; therefore, the transesterification process is required to decrease the viscosity of microalgal lipids before they can be combusted in the engines. However, microalgae are considered as a potential resource in the current biofuel industries; still, it fails at the commercial level. Thus, in this book chapter, we have discussed the microalgal biofuel production and the challenges behind and the future

Challenges and Applications

**Keywords:** microalgae, cultivation, biomass, biodiesel, challenges

production market to fulfill the demands and desires of society.

Today's scientific reports revealed that the world's commercial primary energy needs are mostly coming from fossil fuel sources. It is forecasted that the primary energy demand by 2035 will increase to 54% and still fossil fuels contribute 82% of the global need [1]. Besides, an increase in the world population and their anthropogenic activities, such as transportation, land use, deforestation, industrialization, waste generation, etc., has been changing the natural structure of the earth. These activities lead to severe global climate problems in the present scenario. A remarkable change in the lifestyle of human beings is also building extra pressure on the

Nevertheless, the recent production and consumption models mainly rely on fossil fuel resources, which are affecting the environment and natural resources adversely and irreversibly. It has been reported that the majority of the global CO2 emissions are due to the transport sector and the number of light motor vehicles is estimated to increase to over 2 billion by 2050 [2]. Hence, to address the significant

## **Chapter 11**

*Renewable Energy - Technologies and Applications*

[50] Vassilev SV, Vassileva CG, Vassilev VS. Advantages and disadvantages of composition and properties of biomass in comparison

with coal: An overview. Fuel.

[51] Hroncova E, Ladomersky J, Valicek J, Dzurenda L. Combustion of Biomass Fuel and Residues: Emissions Production Perspective. Developments in Combustion Technology. Rijeka: InTechOpen; 2016. DOI: 10.5772/63793

2015;**158**:330-350

**166**
