Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants

*Md. Emdadul Hoque and Fazlur Rashid*

## **Abstract**

Reduction of conventional fuel has encouraged to find new sources of renewable energy. Oil produced from the pyrolysis method using biomass is considered as an emerging source of renewable energy. Pyrolytic oil produced in pyrolysis needs to be upgraded to produce bio-oil that can be used with conventional fuel. However, pyrolytic oil contains high amounts of oxygen that lower the calorific value of fuel, creates corrosion, and makes the operation unstable. On the other hand, the upgradation process of pyrolytic oil involves solvent and catalyst material that requires a high cost. In this regard, the co-pyrolysis method can be used to upgrade the pyrolytic oil where two or more feedstock materials are involved. The calorific value and oil yield in the co-pyrolysis method are higher than pyrolytic oil. Also, the upgraded oil in the co-pyrolysis method contains low water that can improve the fuel property. Therefore, the co-pyrolysis of biomass waste is an emerging source of energy. Among different biomasses, solid waste and aquatic plants are significantly used as feedstock in the co-pyrolysis method. As a consequence, pressure on conventional fuel can be reduced to fulfill the demand for global energy. Moreover, the associated operating and production cost of the co-pyrolysis method is comparatively low. This method also reduces environmental pollution.

**Keywords:** co-pyrolysis, pyrolytic oil, biomass solid waste, aquatic plants, conventional fuel

## **1. Introduction**

The reduction of conventional fuel sources such as coal, natural gas, and petroleum encourages to search for new sources of renewable energy. Previous literature predicts that coal would be the sole fossil fuel after 2042 [1]. On the other hand, the increase in fossil fuel prices and sustainable effects on the environment are the primary reasons for the use of alternate renewable energy [2–4]. A number of different ways are now underway to search for alternate sources of energy that are environmentally-friendly. However, environmental impact is more apparent after an environmental summit of the earth [5]. Therefore, to reduce environmental warming and pollution, it is required to control emissions produced by fossil fuels. The effective way of reducing environmental pollution and dependency on conventional fuel is to use renewable sources of energy [3, 6, 7].

There are a number of different alternative sources of available energy that can be utilized to substitute conventional sources of energy. The selection of effective and efficient alternative sources of energy is important. In general, an alternate source of energy is suggested to select based on cost, availability, and

environmental impact [4]. In this case, biomass is a prospective source of future energy that is abundant in nature, less costly, and environmental-friendly. Biomass is a significant source of bioenergy that can be utilized to generate energy and used to reduce environmental warming [8]. Biomass energy source is significant because it is the only available renewable resources that can be used to produce all three types of fuels, such as solid (char), liquid (oil), and gas (CH4) [9]. By comparing different biomass conversion methods, such as composting, incineration, landfill, and pyrolysis, it is found that pyrolysis is an effective biomass conversion process [10]. Pyrolysis method can be used to process biomass solids and produce solid, liquid, and gaseous fuel. The pyrolysis method can be used to process biomass solids and produce solid, liquid, and gaseous fuel. This process can also be able to produce the highest quantity of yield in liquid form (~75 wt.%) at a moderate level of temperature (~550 °C) [9]. The remaining quantity of yield can be reduced by changing different operating parameters in the pyrolysis process. The liquid yield produced from the pyrolysis method is called pyrolytic oil and it can be used directly to operate engines, boilers, furnaces, and turbines [11]. Moreover, pyrolytic oil reduces the environmental emissions and global warming [12].

However, pyrolytic oil generated from the pyrolysis method is less efficient on the basis of fuel combustion when compared to conventional fuels, such as diesel, petrol, etc. This is due to the reason that pyrolytic oil usually contains a high quantity of oxygen that creates unnecessary combustion problems. In different previous research, it was found that pyrolytic oil contained approximately 30–60 wt. % of oxygen in the form of water molecules [11, 13–15]. In addition, high oxygen contents in pyrolytic oil cause lower calorific value and instability of operation. As a consequence, it is required to upgrade and improve pyrolytic oil generated in the pyrolysis process.

To improve the quality of pyrolytic oil, it is required to reduce the quantity of dissolved oxygen. It is possible to reduce the dissolved oxygen from pyrolytic oil by catalytic cracking, co-pyrolysis, and catalytic cracking and hydrodeoxygenation (HDO) process.

In the catalytic cracking and hydrodeoxygenation (HDO) method, external catalysts are added in the pyrolysis process. However, the addition of catalysts increases the operating cost of the pyrolysis process. It also increases the number of solid materials at disposal [16]. Overall, this process is costly, complex, and require higher pressure during operation. In contrast, the co-pyrolysis method is an effective and efficient process that can improve the quality of pyrolytic oil.

Therefore, this chapter presents the co-pyrolysis method of biomass feedstocks. This chapter also presents the generation of liquid fuel from solid waste (wood, plastic) and aquatic plants (water hyacinth) using the co-pyrolysis method. Additionally, by using biomass solid wastes (plastic, wood) as feedstock material, the co-pyrolysis method can reduce environmental pollution and help the global waste management system. This method also uses invasive aquatic plants (water hyacinth) as feedstock material and reduces the negative effects of water hyacinth on aquatic flora, fauna. Hence, solid and aquatic plant biomass would be a potential source of energy that produces less impact on the environment.

The outcomes of this chapter will help to decrease the pressure on conventional fuel. On the other hand, the majority of the recent literature shows the use of rice straw, pinewood, and plastic material as feedstocks in the co-pyrolysis method. However, this chapter shows the generation of product yield for two different combinations of feedstocks and compares the performance of them at a different proportion that is rare in previous research. By effectively maintaining the required proportion of biomass feedstock materials, it is possible to generate a significant quantity of solid, liquid, and gas yield. As a consequence, biomass feedstocks would be a feasible option to fulfill the global energy demand.

**67**

**Figure 1.**

*Biomass conversion techniques.*

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

produce charcoal and combustible gases [17].

Biomass can be converted in a number of different ways. The most significant

ways are pyrolysis, gasification, combustion, and liquefaction, as shown in **Figure 1**. On the other hand, all biomass conversion techniques are performed

Pyrolysis is defined as the method of heating organic biomass in absence of oxygen. This is due to the reason that without oxygen, there is no combustion occurred in biomass materials. However, applying heat decomposes the chemical components of biomass materials such as lignin, cellulose, and hemicellulose and

In the pyrolysis method, the produced combustible gases are condensed to a combustible liquid called pyrolytic oil. The other products of the pyrolysis method are CO2, CO, H2, and HC. Therefore, the pyrolysis method generates three types of products, such as solid (charcoal), liquid (bio-oil/pyrolytic oil), and gas (synthetic gas). **Figure 3** presents the overall schematic diagram of the pyrolysis method that

Moreover, in pyrolysis method, biomass feedstock materials are decomposed in

Residue materials unreacted Volatile matte ( ) → ++ 1 11 rs Charcoal Gases (2)

Biomass feedstocks H O residue materials unr → + <sup>2</sup> ( eacted) (1)

Charcoal Volatile matters Gases Charcoal <sup>1</sup> → ++ 22 2 (3)

using three major process technologies, as depicted in **Figure 2**.

pyrolytic oil by the following reaction mechanism Equations [18]:

**2. Biomass conversion techniques**

**2.1 Pyrolysis**

generates pyrolytic oil.

## **2. Biomass conversion techniques**

Biomass can be converted in a number of different ways. The most significant ways are pyrolysis, gasification, combustion, and liquefaction, as shown in **Figure 1**. On the other hand, all biomass conversion techniques are performed using three major process technologies, as depicted in **Figure 2**.

## **2.1 Pyrolysis**

*Gasification*

(HDO) process.

environmental impact [4]. In this case, biomass is a prospective source of future energy that is abundant in nature, less costly, and environmental-friendly. Biomass is a significant source of bioenergy that can be utilized to generate energy and used to reduce environmental warming [8]. Biomass energy source is significant because it is the only available renewable resources that can be used to produce all three types of fuels, such as solid (char), liquid (oil), and gas (CH4) [9]. By comparing different biomass conversion methods, such as composting, incineration, landfill, and pyrolysis, it is found that pyrolysis is an effective biomass conversion process [10]. Pyrolysis method can be used to process biomass solids and produce solid, liquid, and gaseous fuel. The pyrolysis method can be used to process biomass solids and produce solid, liquid, and gaseous fuel. This process can also be able to produce the highest quantity of yield in liquid form (~75 wt.%) at a moderate level of temperature (~550 °C) [9]. The remaining quantity of yield can be reduced by changing different operating parameters in the pyrolysis process. The liquid yield produced from the pyrolysis method is called pyrolytic oil and it can be used directly to operate engines, boilers, furnaces, and turbines [11]. Moreover, pyrolytic oil reduces the

However, pyrolytic oil generated from the pyrolysis method is less efficient on the basis of fuel combustion when compared to conventional fuels, such as diesel, petrol, etc. This is due to the reason that pyrolytic oil usually contains a high quantity of oxygen that creates unnecessary combustion problems. In different previous research, it was found that pyrolytic oil contained approximately 30–60 wt. % of oxygen in the form of water molecules [11, 13–15]. In addition, high oxygen contents in pyrolytic oil cause lower calorific value and instability of operation. As a consequence, it is required to upgrade and improve pyrolytic oil generated in the pyrolysis process. To improve the quality of pyrolytic oil, it is required to reduce the quantity of dissolved oxygen. It is possible to reduce the dissolved oxygen from pyrolytic oil by catalytic cracking, co-pyrolysis, and catalytic cracking and hydrodeoxygenation

In the catalytic cracking and hydrodeoxygenation (HDO) method, external catalysts are added in the pyrolysis process. However, the addition of catalysts increases the operating cost of the pyrolysis process. It also increases the number of solid materials at disposal [16]. Overall, this process is costly, complex, and require higher pressure during operation. In contrast, the co-pyrolysis method is an effec-

Therefore, this chapter presents the co-pyrolysis method of biomass feedstocks. This chapter also presents the generation of liquid fuel from solid waste (wood, plastic) and aquatic plants (water hyacinth) using the co-pyrolysis method. Additionally, by using biomass solid wastes (plastic, wood) as feedstock material, the co-pyrolysis method can reduce environmental pollution and help the global waste management system. This method also uses invasive aquatic plants (water hyacinth) as feedstock material and reduces the negative effects of water hyacinth on aquatic flora, fauna. Hence, solid and aquatic plant biomass would be a potential

The outcomes of this chapter will help to decrease the pressure on conventional fuel. On the other hand, the majority of the recent literature shows the use of rice straw, pinewood, and plastic material as feedstocks in the co-pyrolysis method. However, this chapter shows the generation of product yield for two different combinations of feedstocks and compares the performance of them at a different proportion that is rare in previous research. By effectively maintaining the required proportion of biomass feedstock materials, it is possible to generate a significant quantity of solid, liquid, and gas yield. As a consequence, biomass feedstocks would

tive and efficient process that can improve the quality of pyrolytic oil.

source of energy that produces less impact on the environment.

be a feasible option to fulfill the global energy demand.

environmental emissions and global warming [12].

**66**

Pyrolysis is defined as the method of heating organic biomass in absence of oxygen. This is due to the reason that without oxygen, there is no combustion occurred in biomass materials. However, applying heat decomposes the chemical components of biomass materials such as lignin, cellulose, and hemicellulose and produce charcoal and combustible gases [17].

In the pyrolysis method, the produced combustible gases are condensed to a combustible liquid called pyrolytic oil. The other products of the pyrolysis method are CO2, CO, H2, and HC. Therefore, the pyrolysis method generates three types of products, such as solid (charcoal), liquid (bio-oil/pyrolytic oil), and gas (synthetic gas). **Figure 3** presents the overall schematic diagram of the pyrolysis method that generates pyrolytic oil.

Moreover, in pyrolysis method, biomass feedstock materials are decomposed in pyrolytic oil by the following reaction mechanism Equations [18]:

$$\text{Biomass feedstocks} \rightarrow \text{H}\_2\text{O} + \text{residue materials} \,(\text{unreacted}) \tag{1}$$

Residue materials unreacted Volatile matte ( ) → ++ 1 11 rs Charcoal Gases (2)

$$\text{Charcoal}\_1 \rightarrow \text{Volatile matiters}\_2 + \text{Gases}\_2 + \text{Charcoal}\_2 \tag{3}$$

**Figure 1.** *Biomass conversion techniques.*

#### **Figure 3.**

Therefore, in the biomass pyrolysis method, firstly, moisture contents, and volatile matters are lost as presents by Eq. (1). Secondly, unreacted residue materials are transformed into volatile matters, as shown in Eq. (2). Finally, charcoal material is re-arranged at a slower step, as shown in Eq. (3).

Depending on the reaction temperature, residence time, and rate of heating, the pyrolysis process can be classified as fast, slow, and flash pyrolysis. Pyrolysis process usually occurs in a fixed bed, fluidized bed, moving bed, suspended bed reactors.

However, the generated pyrolytic oil in the pyrolysis process contains a higher quantity of oxygen that decreases internal combustion engines' efficiency. Therefore, up-gradation of pyrolytic oil generated from the pyrolysis method is necessary. The pyrolytic oil generated from the pyrolysis method can be upgraded by esterification, emulsification, or catalytic cracking. All these up-gradation methods include extra operating costs for the pyrolysis process and they are rather costly. The other effective method of producing high-quality pyrolytic oil is the co-pyrolysis method that can produce high-quality pyrolytic oil with less quantity of oxygen.

**69**

**Figure 5.**

*Overall process of co-pyrolysis [9].*

**2.2 Co-pyrolysis**

*Upgradation methods of pyrolytic oil [19].*

**Figure 4.**

co-pyrolysis, and condensation.

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

Co-pyrolysis is the process where two or more feedstock materials include to improve the quality of pyrolytic oil in absence of oxygen at a moderate temperature (~500 °C). Effectiveness and simplicity are two important characteristics of the

It is seen from **Figure 5** that, in the co-pyrolysis method, two or more feedstock materials are dried and ground to prepare feedstock material. After that inert gases are required to add to the reactor. Inert gases use to speed up the sweeping vapors of feedstock materials from the pyrolysis region to the condenser region. Nitrogen gas is used as an inert gas in the co-pyrolysis process due to its low cost. Initially, charcoal and combustible gases are produced. After condensation, combustible gases generate upgraded pyrolytic oil. Therefore, the co-pyrolysis method requires three steps for the generation of pyrolytic oil, such as preparation of feedstock materials,

Drying of feedstock material can be done using the oven method at a higher temperature (~105 °C) for 1 day. The drying process is required to remove the

co-pyrolysis process. **Figure 5** shows the overall process of co-pyrolysis.

**Figure 4** shows the upgradation methods of pyrolytic oil generated from biomass pyrolysis method.

**Figure 4.** *Upgradation methods of pyrolytic oil [19].*

## **2.2 Co-pyrolysis**

*Gasification*

**Figure 2.**

**Figure 3.**

*Flow diagram of the pyrolysis process.*

*Biomass conversion process technologies [17].*

**68**

of oxygen.

biomass pyrolysis method.

Therefore, in the biomass pyrolysis method, firstly, moisture contents, and volatile matters are lost as presents by Eq. (1). Secondly, unreacted residue materials are transformed into volatile matters, as shown in Eq. (2). Finally, charcoal material

quantity of oxygen that decreases internal combustion engines' efficiency. Therefore, up-gradation of pyrolytic oil generated from the pyrolysis method is necessary. The pyrolytic oil generated from the pyrolysis method can be upgraded by esterification, emulsification, or catalytic cracking. All these up-gradation methods include extra operating costs for the pyrolysis process and they are rather costly. The other effective method of producing high-quality pyrolytic oil is the co-pyrolysis method that can produce high-quality pyrolytic oil with less quantity

**Figure 4** shows the upgradation methods of pyrolytic oil generated from

Depending on the reaction temperature, residence time, and rate of heating, the pyrolysis process can be classified as fast, slow, and flash pyrolysis. Pyrolysis process usually occurs in a fixed bed, fluidized bed, moving bed, suspended bed reactors. However, the generated pyrolytic oil in the pyrolysis process contains a higher

is re-arranged at a slower step, as shown in Eq. (3).

Co-pyrolysis is the process where two or more feedstock materials include to improve the quality of pyrolytic oil in absence of oxygen at a moderate temperature (~500 °C). Effectiveness and simplicity are two important characteristics of the co-pyrolysis process. **Figure 5** shows the overall process of co-pyrolysis.

It is seen from **Figure 5** that, in the co-pyrolysis method, two or more feedstock materials are dried and ground to prepare feedstock material. After that inert gases are required to add to the reactor. Inert gases use to speed up the sweeping vapors of feedstock materials from the pyrolysis region to the condenser region. Nitrogen gas is used as an inert gas in the co-pyrolysis process due to its low cost. Initially, charcoal and combustible gases are produced. After condensation, combustible gases generate upgraded pyrolytic oil. Therefore, the co-pyrolysis method requires three steps for the generation of pyrolytic oil, such as preparation of feedstock materials, co-pyrolysis, and condensation.

Drying of feedstock material can be done using the oven method at a higher temperature (~105 °C) for 1 day. The drying process is required to remove the

**Figure 5.** *Overall process of co-pyrolysis [9].*


#### **Table 1.**

*Optimum operating conditions of co-pyrolysis method [9].*

moisture contents in the feedstock material. However, for industrial purposes, the amount of required heat is higher than lab-scale. Hence, process integration is used to heat feedstock materials [9].

The optimum temperature of the co-pyrolysis process is considered as 400 ~ 600 °C. At this temperature, approximately 45 wt. % of pyrolytic oil is usually produced from feedstock material [9]. **Table 1** presents the optimum operating conditions of co-pyrolysis method for different feedstock materials.

In this chapter, pinewood with plastic material, and rice straw with water hyacinth material is considered as feedstock materials for the co-pyrolysis process. Pinewood [20, 21] and waste plastic [22, 23] materials are commonly available in environment that can create environmental pollution.

## **3. Reaction parameters of co-pyrolysis process**

Reactions of the co-pyrolysis method are complex and it includes a number of different co-pyrolysis reactions. The biomass co-pyrolysis process and their reactions depend on different parameters, such as the effect of feedstock materials, blending ratio, rate of heat, temperature, reactor type, etc. This section of the chapter presents the effect of different parameters on the co-pyrolysis method.

#### **3.1 Effect of different feedstocks**

Biomass feed materials consist of lignin, cellulose, and hemicellulose [24]. These components generate synergistic effects on the thermal behavior of biomass. It is considered that the cracking of biomass depends on the H and OH radicals release during biomass pyrolysis [25, 26]. On the other hand, hemicellulose components serve effects of promotion on biomass conversion during co-pyrolysis process [27].

**Table 2** shows the characteristics of different biomass materials.

#### **3.2 Effect of blending ratio**

The blending ratio is defined as the proportion of biomass in the blend of feedstock materials during co-pyrolysis. In the co-pyrolysis method, the


**71**

feedstock material.

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

degree of synergistic effect.

with the increase in the heating rate.

**3.3 Effect of rate of heat**

higher volatile yields [37].

**3.4 Effect of temperature**

**3.5 Effect of types of reactor**

generated quantity of gas, liquid, and solid materials depends on the blending ratio of feedstock material [33]. It was found that increasing biomass blending ratio reduces the solid charcoal generation, while liquid and gas production increases [34]. The blending ratio of biomass materials can also influence the

The rate of heating is a significant factor that can affect the biomass co-pyrolysis process. The biomass co-pyrolysis process can be distinguished if the rate of heat is low. At a low heating rate, only additive behavior of biomass materials occurs. On the other hand, the devolatilization process of biomass materials becomes slower

Synergism of biomass feedstock materials is favored by the increased heating rate of feedstock material [27, 35, 36]. It was found that low heating rate caused lack of synergies. Moreover, a high rate of heat during co-pyrolysis generally produces

The temperature in the co-pyrolysis process is an important factor for the generation of solid (charcoal), liquid (pyrolytic oil), and gas. By increasing the temperature inside the co-pyrolysis reactor, it is possible to decrease the production of charcoal from biomass co-pyrolysis. As a consequence, the overall efficiency of the co-pyrolysis method can be increased by increasing the temperature [38, 39].

Different types of reactors, such as fixed bed, fluidized bed, TG, drop style, auger are commonly used in pyrolysis and co-pyrolysis process. In this chapter, the fixed bed reactor is considered for biomass feedstock materials. However, the TG

In a fixed bed pyrolysis reactor, a large quantity of feedstock materials provides intimate contact between fuel particles and their generated volatiles. Due to this phenomena, synergistic effect is occurred for gas and pyrolysis product yield [40]. Fluidized bed and drop style type reactors are fast pyrolysis reactors that can be used to carry the co-pyrolysis process. Auger reactor is more effective than fixedbed reactor for co-pyrolysis process. Auger type reactor usually generates higher

Availability is one of the important factors for the selection of alternative energy sources. With respect to this condition, biomass is considered a potential energy source all over the world. It can be generated from the forest (wood), agriculture (rice husk, rice straw), solid waste (plastic), aquatic plants (water hyacinth), etc. In this work, rice straw, plastic, water hyacinth, and pinewood are considered as

Biomass feedstock materials are required to collect from the local market. They contain moisture and volatile matters that can reduce the overall efficiency of the pyrolysis process. To overcome this problem, biomass materials are dried using the oven for lab-scale operation and process heat through industrial applications. After

reactor is most commonly used during the co-pyrolysis method.

**4. Sample preparation and feedstocks for co-pyrolysis**

liquid product yield than fixed-bed reactor [41].

#### **Table 2.**

*Characteristics of different biomass materials.*

generated quantity of gas, liquid, and solid materials depends on the blending ratio of feedstock material [33]. It was found that increasing biomass blending ratio reduces the solid charcoal generation, while liquid and gas production increases [34]. The blending ratio of biomass materials can also influence the degree of synergistic effect.

## **3.3 Effect of rate of heat**

*Gasification*

Wood, plastic, rice husk, rice straw, water

hyacinth

**Table 1.**

to heat feedstock materials [9].

*Optimum operating conditions of co-pyrolysis method [9].*

**3.1 Effect of different feedstocks**

**3.2 Effect of blending ratio**

**70**

**Table 2.**

*Characteristics of different biomass materials.*

**Feedstock materials Lignin (wt. %) Cellulose (wt. %) Hemicellulose (wt. %)** Pinewood 24 [28] 42 [28] 23 [28] Water hyacinth 3 ~ 28 [29] ~30 [30] ~25 [30] Rice straw 16.5 [31] 29.8 [31] 33.3 [31] Waste plastic (polystyrene) 10 ~ 15 [32] 35 ~ 55 [32] 20 ~ 40 [32]

The blending ratio is defined as the proportion of biomass in the blend of feedstock materials during co-pyrolysis. In the co-pyrolysis method, the

moisture contents in the feedstock material. However, for industrial purposes, the amount of required heat is higher than lab-scale. Hence, process integration is used

**Feedstock materials Temperature(°C) Inert gas Pyrolytic oil (wt.%)**

300 ~ 500 N2 45–75

The optimum temperature of the co-pyrolysis process is considered as 400 ~ 600 °C. At this temperature, approximately 45 wt. % of pyrolytic oil is usually produced from feedstock material [9]. **Table 1** presents the optimum operating

In this chapter, pinewood with plastic material, and rice straw with water hyacinth material is considered as feedstock materials for the co-pyrolysis process. Pinewood [20, 21] and waste plastic [22, 23] materials are commonly available in

Reactions of the co-pyrolysis method are complex and it includes a number of different co-pyrolysis reactions. The biomass co-pyrolysis process and their reactions depend on different parameters, such as the effect of feedstock materials, blending ratio, rate of heat, temperature, reactor type, etc. This section of the chapter presents the effect of different parameters on the co-pyrolysis method.

Biomass feed materials consist of lignin, cellulose, and hemicellulose [24]. These components generate synergistic effects on the thermal behavior of biomass. It is considered that the cracking of biomass depends on the H and OH radicals release during biomass pyrolysis [25, 26]. On the other hand, hemicellulose components serve effects of promotion on biomass conversion during co-pyrolysis process [27].

**Table 2** shows the characteristics of different biomass materials.

conditions of co-pyrolysis method for different feedstock materials.

environment that can create environmental pollution.

**3. Reaction parameters of co-pyrolysis process**

The rate of heating is a significant factor that can affect the biomass co-pyrolysis process. The biomass co-pyrolysis process can be distinguished if the rate of heat is low. At a low heating rate, only additive behavior of biomass materials occurs. On the other hand, the devolatilization process of biomass materials becomes slower with the increase in the heating rate.

Synergism of biomass feedstock materials is favored by the increased heating rate of feedstock material [27, 35, 36]. It was found that low heating rate caused lack of synergies. Moreover, a high rate of heat during co-pyrolysis generally produces higher volatile yields [37].

## **3.4 Effect of temperature**

The temperature in the co-pyrolysis process is an important factor for the generation of solid (charcoal), liquid (pyrolytic oil), and gas. By increasing the temperature inside the co-pyrolysis reactor, it is possible to decrease the production of charcoal from biomass co-pyrolysis. As a consequence, the overall efficiency of the co-pyrolysis method can be increased by increasing the temperature [38, 39].

### **3.5 Effect of types of reactor**

Different types of reactors, such as fixed bed, fluidized bed, TG, drop style, auger are commonly used in pyrolysis and co-pyrolysis process. In this chapter, the fixed bed reactor is considered for biomass feedstock materials. However, the TG reactor is most commonly used during the co-pyrolysis method.

In a fixed bed pyrolysis reactor, a large quantity of feedstock materials provides intimate contact between fuel particles and their generated volatiles. Due to this phenomena, synergistic effect is occurred for gas and pyrolysis product yield [40]. Fluidized bed and drop style type reactors are fast pyrolysis reactors that can be used to carry the co-pyrolysis process. Auger reactor is more effective than fixedbed reactor for co-pyrolysis process. Auger type reactor usually generates higher liquid product yield than fixed-bed reactor [41].

## **4. Sample preparation and feedstocks for co-pyrolysis**

Availability is one of the important factors for the selection of alternative energy sources. With respect to this condition, biomass is considered a potential energy source all over the world. It can be generated from the forest (wood), agriculture (rice husk, rice straw), solid waste (plastic), aquatic plants (water hyacinth), etc. In this work, rice straw, plastic, water hyacinth, and pinewood are considered as feedstock material.

Biomass feedstock materials are required to collect from the local market. They contain moisture and volatile matters that can reduce the overall efficiency of the pyrolysis process. To overcome this problem, biomass materials are dried using the oven for lab-scale operation and process heat through industrial applications. After drying, biomass feedstock materials are crushed and sieved to a particle size of 0.5 ~ 2 mm [42]. Thermogravimetric analysis (TGA) can be carried out to find the measurement of moisture content, thermal degradation, fixed, and volatile carbons in biomass feedstock materials.

Characterizing of biomass feed materials is significant because it provides C, H, N, S, moisture, ash, fixed carbon, and volatiles. **Table 3** shows the ultimate analysis and **Table 4** presents a proximate analysis of rice straw, water hyacinth, pinewood, and plastic biomass materials.

The heating value of biomass feedstock materials is another significant property that can affect the overall efficiency of the co-pyrolysis method. **Table 5** presents the heating value of rice straw, water hyacinth, pinewood, and waste plastic materials.

It is seen from **Table 5** that plastic material generates the highest quantity of heat when combusts. On the other hand, they are available as waste material in the natural environment.

The co-pyrolysis method can use two or more feedstock materials, therefore, this chapter presents and compares the performance of pinewood and waste plastic biomass with rice straw and water hyacinth aquatic plants.

In the co-pyrolysis process, rice straw, water hyacinth, pinewood, and waste plastic material was used to perform the experiment in a fixed bed reactor, as shown in **Figure 6**. The feedstock materials were prepared with a nominal size of 5 mm. All the biomass feedstock materials were added in the fixed bed reactor and nitrogen was used as the carrier gas. An external electrical heater was used to externally heat up the reactor during the co-pyrolysis process. The heater increased the reactor temperature to around 60 °C per minute. The final reactor temperature during the co-pyrolysis process was 550 °C. The overall reaction time for the biomass copyrolysis process was ~30 min. The solid and liquid product yields were collected by


#### **Table 3.**

*Ultimate analysis of biomass feedstock materials.*


**73**

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

*Heating value of biomass feedstock materials.*

**Table 5.**

**Figure 6.**

**Feedstock materials Heating value (MJ/kg)** Pinewood 18–21.5 Water hyacinth 14.6 Rice straw 14–15.1 Waste plastic (polystyrene) 40

weight basis, while gas yields collected in a gas reservoir bag. After that, a gas analyzer was required to analyze the composition of gas yield generated in co-pyrolysis

*Schematic diagram of the co-pyrolysis process of rice straw, water hyacinth, pinewood, and plastic biomass.*

Co-pyrolysis of pinewood and waste plastic feedstock material is a potential source

In pinewood and waste plastic feedstocks, the products of charcoal production do not depend on the addition of waste plastics. It was also found that very little quantity of charcoal produced from the co-pyrolysis of waste plastic [45, 46]. While, in the co-pyrolysis of rice straw and water hyacinth feedstocks, the production of bio-oils depends on the reactor temperature, and with the increase of reactor temperature up to 400 °C, the pyrolytic oil production is also increased. After that,

of energy. On the other hand, rice straw and water hyacinth is another significant source of biomass energy that can be used as feedstocks in the co-pyrolysis process. Individually rice straw, plastic, water hyacinth, and pinewood biomass materials, when used in the pyrolysis process, produce less efficient pyrolytic oil that creates unnecessary combustion problems due to high oxygen contents. As a consequence, different proportions of two or more feedstock materials are usually used in the co-pyrolysis method that can provide better performance. This section of the chapter presents the performance analysis of pinewood with waste plastic and rice straw with water hyacinth biomass feedstock materials during the co-pyrolysis method at different proportions of feedstock materials. The product yields were solid (charcoal), liquid (pyrolytic oil), and gas. Likewise. the co-pyrolysis of rice straw, water hyacinth, pinewood, and

plastic materials provide product yield of charcoal, pyrolytic oil, and gas.

above temperature 400 °C, generation of pyrolytic oil decreases [42].

of rice straw, water hyacinth, pinewood, and plastic materials.

**5. Co-pyrolysis using biomass solids and aquatic plants**

#### **Table 4.**

*Proximate analysis of biomass feedstock materials.*


#### **Table 5.**

*Gasification*

materials.

natural environment.

in biomass feedstock materials.

and plastic biomass materials.

**72**

**Table 4.**

**Feedstock materials**

Water hyacinth

Waste plastic (polystyrene) [44]

*Proximate analysis of biomass feedstock materials.*

*Ultimate analysis of biomass feedstock materials.*

[42]

**Table 3.**

**Fixed carbon (wt.%)**

**Feedstock materials Carbon** 

**Moisture (wt.%)**

Pinewood [43] 17.90 14.2 67.70 45

drying, biomass feedstock materials are crushed and sieved to a particle size of 0.5 ~ 2 mm [42]. Thermogravimetric analysis (TGA) can be carried out to find the measurement of moisture content, thermal degradation, fixed, and volatile carbons

Characterizing of biomass feed materials is significant because it provides C, H, N, S, moisture, ash, fixed carbon, and volatiles. **Table 3** shows the ultimate analysis and **Table 4** presents a proximate analysis of rice straw, water hyacinth, pinewood,

The heating value of biomass feedstock materials is another significant property that can affect the overall efficiency of the co-pyrolysis method. **Table 5** presents the heating value of rice straw, water hyacinth, pinewood, and waste plastic

It is seen from **Table 5** that plastic material generates the highest quantity of heat when combusts. On the other hand, they are available as waste material in the

The co-pyrolysis method can use two or more feedstock materials, therefore, this chapter presents and compares the performance of pinewood and waste plastic

In the co-pyrolysis process, rice straw, water hyacinth, pinewood, and waste plastic material was used to perform the experiment in a fixed bed reactor, as shown in **Figure 6**. The feedstock materials were prepared with a nominal size of 5 mm. All the biomass feedstock materials were added in the fixed bed reactor and nitrogen was used as the carrier gas. An external electrical heater was used to externally heat up the reactor during the co-pyrolysis process. The heater increased the reactor temperature to around 60 °C per minute. The final reactor temperature during the co-pyrolysis process was 550 °C. The overall reaction time for the biomass copyrolysis process was ~30 min. The solid and liquid product yields were collected by

> **(C) (wt.%)**

Pinewood [43] 47.5 6.50 0.095 ~0.13 Water hyacinth [42] 34.85 6.50 0.8 1.5 Rice straw [42] 36.1 5.20 0.6 0.30 Waste plastic (polystyrene) [44] 90.40 8.60 0.070 0.080

biomass with rice straw and water hyacinth aquatic plants.

Rice straw [42] 6.90 11.7 78.1 15.2

**Volatile matters (wt.%)**

4.90 13.15 69.2 25.50

**Hydrogen (H2) (wt.%)**

**Nitrogen (N2) (wt.%)**

~0.7–12 0.20 99.31 0.50

**Ash (wt.%)**

**Sulfur (S) (wt.%)** *Heating value of biomass feedstock materials.*

**Figure 6.** *Schematic diagram of the co-pyrolysis process of rice straw, water hyacinth, pinewood, and plastic biomass.*

weight basis, while gas yields collected in a gas reservoir bag. After that, a gas analyzer was required to analyze the composition of gas yield generated in co-pyrolysis of rice straw, water hyacinth, pinewood, and plastic materials.

## **5. Co-pyrolysis using biomass solids and aquatic plants**

Co-pyrolysis of pinewood and waste plastic feedstock material is a potential source of energy. On the other hand, rice straw and water hyacinth is another significant source of biomass energy that can be used as feedstocks in the co-pyrolysis process. Individually rice straw, plastic, water hyacinth, and pinewood biomass materials, when used in the pyrolysis process, produce less efficient pyrolytic oil that creates unnecessary combustion problems due to high oxygen contents. As a consequence, different proportions of two or more feedstock materials are usually used in the co-pyrolysis method that can provide better performance. This section of the chapter presents the performance analysis of pinewood with waste plastic and rice straw with water hyacinth biomass feedstock materials during the co-pyrolysis method at different proportions of feedstock materials. The product yields were solid (charcoal), liquid (pyrolytic oil), and gas. Likewise. the co-pyrolysis of rice straw, water hyacinth, pinewood, and plastic materials provide product yield of charcoal, pyrolytic oil, and gas.

In pinewood and waste plastic feedstocks, the products of charcoal production do not depend on the addition of waste plastics. It was also found that very little quantity of charcoal produced from the co-pyrolysis of waste plastic [45, 46]. While, in the co-pyrolysis of rice straw and water hyacinth feedstocks, the production of bio-oils depends on the reactor temperature, and with the increase of reactor temperature up to 400 °C, the pyrolytic oil production is also increased. After that, above temperature 400 °C, generation of pyrolytic oil decreases [42].

### **5.1 Performance analysis**

In the co-pyrolysis method of pinewood-waste plastic and rice straw-water hyacinth, it was observed that liquid yield generation was higher in pinewoodwaste plastic feedstocks than rice straw-water hyacinth feedstocks. This is due to the higher heating value of pinewood and plastic material than water hyacinth. The porosity of water hyacinth feedstocks can also negatively affect the generation of product yield during the co-pyrolysis process. In addition, the density of rice straw and water hyacinth is lower than the density of pinewood and waste plastic that can negatively influence the generation of pyrolytic oil for the co-pyrolysis method.

In this process, initially pinewood with waste plastic (polystyrene) and rice straw with water hyacinth materials were added in a 1: 1 ratio.

**Figure 7** presents the generation of liquid yield from the co-pyrolysis process for pinewood-plastic (polystyrene) and rice straw-water hyacinth feedstock materials. It is seen from **Figure 7** that the liquid yield (pyrolytic oil) of pinewood with plastic (polystyrene) feedstocks in co-pyrolysis was higher than rice straw with water hyacinth feedstock materials at 400 °C temperature [9, 42].

In the co-pyrolysis method, the amount of solid, liquid, and gas yield depends on the type of biomass feedstocks and the proportion at which they are added in the co-pyrolysis process. In this chapter, three different ratios of feedstocks have been considered to analyze the performance of co-pyrolysis.

The co-pyrolysis of rice straw with water hyacinth feedstock materials produced the highest yield of liquid (pyrolytic oil) than solid (charcoal) and gas yield at an equal proportion of rice straw and water hyacinth (1:1). It was also found that with the increase of water hyacinth proportion with rice straw, the liquid (pyrolytic oil) yield was decreased but solid (charcoal) yield increased, while gas yield remained almost same [42]. This trends were statistically significant. On the other hand, a high proportion of rice straw with water hyacinth reduced the liquid yield from the liquid yield of an equal amount of rice straw and water hyacinth, as shown in **Figure 8**.

**Figure 9** presents the mean and standard deviation of the product yield wt. % for three different compositions of rice straw and water hyacinth. It is seen from **Figure 9** that the variation of solid yield (charcoal) with the change of composition of rice husk and water hyacinth was lower than liquid (pyrolytic oil) and gas yield.

**Figure 10** shows the product yield of co-pyrolysis for different proportions of pinewood and waste plastic (polystyrene) biomass materials. It was found that

**75**

**Figure 9.**

**Figure 8.**

(polystyrene), as shown in **Figure 10**.

*hyacinth (2.5)) in co-pyrolysis process.*

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

co-pyrolysis of pinewood with waste plastic (polystyrene) feedstock materials produced the highest yield of liquid (pyrolytic oil) than solid (charcoal) and gas yield at an equal proportion of pinewood and waste plastic (polystyrene) (1:1). It was also found that with the increase of waste plastic (polystyrene) proportion with pinewood, the liquid (pyrolytic oil) yield was increased but solid (charcoal) yield decreased [47]. This trends were statistically significant. On the other hand, a high proportion of pinewood with waste plastic (polystyrene) reduced the liquid yield from the liquid yield of an equal amount of pinewood with waste plastic

*Statistical analysis of product yield generation from the different proportion of rice straw and water hyacinth feedstocks (rice straw (1): Water hyacinth (1), rice straw (2.5): Water hyacinth (1), and rice straw (1): Water* 

*Product yield generation from different proportion of rice straw and water hyacinth in co-pyrolysis process [42].*

**Figure 7.** *Pyrolytic oil generation from biomass co-pyrolysis process at 400 °C [9, 42].*

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

*Gasification*

**5.1 Performance analysis**

In the co-pyrolysis method of pinewood-waste plastic and rice straw-water hyacinth, it was observed that liquid yield generation was higher in pinewoodwaste plastic feedstocks than rice straw-water hyacinth feedstocks. This is due to the higher heating value of pinewood and plastic material than water hyacinth. The porosity of water hyacinth feedstocks can also negatively affect the generation of product yield during the co-pyrolysis process. In addition, the density of rice straw and water hyacinth is lower than the density of pinewood and waste plastic that can negatively influence the generation of pyrolytic oil for the co-pyrolysis method. In this process, initially pinewood with waste plastic (polystyrene) and rice

**Figure 7** presents the generation of liquid yield from the co-pyrolysis process for pinewood-plastic (polystyrene) and rice straw-water hyacinth feedstock materials. It is seen from **Figure 7** that the liquid yield (pyrolytic oil) of pinewood with plastic (polystyrene) feedstocks in co-pyrolysis was higher than rice straw with water

In the co-pyrolysis method, the amount of solid, liquid, and gas yield depends on the type of biomass feedstocks and the proportion at which they are added in the co-pyrolysis process. In this chapter, three different ratios of feedstocks have been

The co-pyrolysis of rice straw with water hyacinth feedstock materials produced the highest yield of liquid (pyrolytic oil) than solid (charcoal) and gas yield at an equal proportion of rice straw and water hyacinth (1:1). It was also found that with the increase of water hyacinth proportion with rice straw, the liquid (pyrolytic oil) yield was decreased but solid (charcoal) yield increased, while gas yield remained almost same [42]. This trends were statistically significant. On the other hand, a high proportion of rice straw with water hyacinth reduced the liquid yield from the liquid yield of an equal amount of rice straw and water hyacinth, as shown in **Figure 8**. **Figure 9** presents the mean and standard deviation of the product yield wt. % for three different compositions of rice straw and water hyacinth. It is seen from **Figure 9** that the variation of solid yield (charcoal) with the change of composition of rice husk and water hyacinth was lower than liquid (pyrolytic oil) and gas yield. **Figure 10** shows the product yield of co-pyrolysis for different proportions of pinewood and waste plastic (polystyrene) biomass materials. It was found that

straw with water hyacinth materials were added in a 1: 1 ratio.

hyacinth feedstock materials at 400 °C temperature [9, 42].

considered to analyze the performance of co-pyrolysis.

**74**

**Figure 7.**

*Pyrolytic oil generation from biomass co-pyrolysis process at 400 °C [9, 42].*

**Figure 8.** *Product yield generation from different proportion of rice straw and water hyacinth in co-pyrolysis process [42].*

#### **Figure 9.**

*Statistical analysis of product yield generation from the different proportion of rice straw and water hyacinth feedstocks (rice straw (1): Water hyacinth (1), rice straw (2.5): Water hyacinth (1), and rice straw (1): Water hyacinth (2.5)) in co-pyrolysis process.*

co-pyrolysis of pinewood with waste plastic (polystyrene) feedstock materials produced the highest yield of liquid (pyrolytic oil) than solid (charcoal) and gas yield at an equal proportion of pinewood and waste plastic (polystyrene) (1:1). It was also found that with the increase of waste plastic (polystyrene) proportion with pinewood, the liquid (pyrolytic oil) yield was increased but solid (charcoal) yield decreased [47]. This trends were statistically significant. On the other hand, a high proportion of pinewood with waste plastic (polystyrene) reduced the liquid yield from the liquid yield of an equal amount of pinewood with waste plastic (polystyrene), as shown in **Figure 10**.

#### **Figure 10.**

*Product yield generation from different proportion of pinewood and waste plastic (polystyrene) in co-pyrolysis process [47].*

**Figure 11** presents the mean and standard deviation of the product yield wt. % for three different compositions of pinewood and plastic (polystyrene) feedstocks. It is seen from **Figure 11** that the variation of a gas yield with the change of composition of pinewood and plastic (polystyrene) was lower than liquid (pyrolytic oil) and solid yield (charcoal) yield.

#### **5.2 Characteristics analysis**

In the co-pyrolysis process, the quality of the generated pyrolytic oil is better than the pyrolysis process. As a consequence, the oxygen content in the pyrolytic

#### **Figure 11.**

*Statistical analysis of product yield generation from the different proportion of pinewood and plastic (polystyrene) feedstocks (pinewood (1): Plastic (polystyrene) (1), pinewood (1): Plastic (polystyrene) (2.5), and pinewood (2): Plastic (polystyrene) (1)) in co-pyrolysis process.*

**77**

**Acknowledgements**

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

**Feedstock materials Calorific value** 

*Calorific value of product yield of co-pyrolysis process.*

related characteristics.

Pinewood- plastic (polystyrene) [47]

**Table 6.**

**6. Conclusion**

oil generated from the co-pyrolysis method is lower than the pyrolysis process. However, to improve or upgrade pyrolytic oil in the pyrolysis method requires an intermediate process that increases the complexity and cost. Hence, this chapter considers only the co-pyrolysis process of biomass feedstock materials and their

Rice straw-water hyacinth [48] 32 ~ 42 33 ~ 42 45.5

**(MJ/kg) of solids**

**Calorific value (MJ/kg) of liquids**

33 ~ 45 32 ~ 45 45.5

**Calorific value (MJ/kg) of Diesel**

feedstock materials in pyrolysis and co-pyrolysis process.

However, the calorific value of pyrolytic oil and gas generated in the co-pyrolysis process for pinewood-waste plastic or rice straw-water hyacinth was higher than the calorific value of product yield when used only pinewood or rice straw or water hyacinth feedstock biomass. **Table 6** presents the calorific value of different

Overall, the generation of liquid yield (pyrolytic oil) and solid yield (charcoal) in the co-pyrolysis method increases with the increase of temperature of the pyrolysis reactor. However, the required temperature of the co-pyrolysis process (300–450 °C)

Biomass is a bio-renewable source of energy. It can be used to generate energy through the pyrolysis and co-pyrolysis process. The generated liquid and gas yield in the pyrolysis and co-pyrolysis method can be used with conventional fuel. However, due to higher dissolved oxygen in pyrolytic oil produced in the pyrolysis process, they are required to be improved or upgraded that makes the process complex and costly. Therefore, the co-pyrolysis process is used that can generate better quality and, upgraded liquid and gas yield. The co-pyrolysis process requires a lower reactor temperature than the pyrolysis process. In this study, co-pyrolysis of rice straw with water hyacinth and pinewood with waste plastic feedstock materials have been analyzed. It is seen that with the increase of pyrolysis reactor temperature, the liquid yield (pyrolytic oil) production also increases. However, if the reactor temperature exceeds 400 °C then the generation of liquid yield decreases. On the other hand, the generation of solid (charcoal), liquid (pyrolytic oil), and gas yield depend on the proportion of feedstock biomasses in the co-pyrolysis process. The calorific value of product yield in the co-pyrolysis process is higher than the pyrolysis process and comparable with conventional fuel, such as diesel. Therefore, the biomass co-pyrolysis process would be a potential source of bio-renewable energy that can fulfill the global energy demand with conventional fuel.

Authors would like to acknowledge the department of Mechanical Engineering, Rajshahi University of Engineering & Technology, Bangladesh for the support of accessing the laboratory facilities to study the pyrolysis and co-pyrolysis process.

is lower than the temperature required for the pyrolysis process (550–750 °C).

Rice straw-water hyacinth [48] 32 ~ 42 33 ~ 42 45.5

#### *Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

## **Table 6.**

*Gasification*

**Figure 10.**

*process [47].*

**76**

**Figure 11.**

*Statistical analysis of product yield generation from the different proportion of pinewood and plastic (polystyrene) feedstocks (pinewood (1): Plastic (polystyrene) (1), pinewood (1): Plastic (polystyrene) (2.5),* 

**Figure 11** presents the mean and standard deviation of the product yield wt. % for three different compositions of pinewood and plastic (polystyrene) feedstocks. It is seen from **Figure 11** that the variation of a gas yield with the change of composition of pinewood and plastic (polystyrene) was lower than liquid (pyrolytic oil)

*Product yield generation from different proportion of pinewood and waste plastic (polystyrene) in co-pyrolysis* 

In the co-pyrolysis process, the quality of the generated pyrolytic oil is better than the pyrolysis process. As a consequence, the oxygen content in the pyrolytic

*and pinewood (2): Plastic (polystyrene) (1)) in co-pyrolysis process.*

and solid yield (charcoal) yield.

**5.2 Characteristics analysis**

*Calorific value of product yield of co-pyrolysis process.*

oil generated from the co-pyrolysis method is lower than the pyrolysis process. However, to improve or upgrade pyrolytic oil in the pyrolysis method requires an intermediate process that increases the complexity and cost. Hence, this chapter considers only the co-pyrolysis process of biomass feedstock materials and their related characteristics.

However, the calorific value of pyrolytic oil and gas generated in the co-pyrolysis process for pinewood-waste plastic or rice straw-water hyacinth was higher than the calorific value of product yield when used only pinewood or rice straw or water hyacinth feedstock biomass. **Table 6** presents the calorific value of different feedstock materials in pyrolysis and co-pyrolysis process.

Overall, the generation of liquid yield (pyrolytic oil) and solid yield (charcoal) in the co-pyrolysis method increases with the increase of temperature of the pyrolysis reactor. However, the required temperature of the co-pyrolysis process (300–450 °C) is lower than the temperature required for the pyrolysis process (550–750 °C).

## **6. Conclusion**

Biomass is a bio-renewable source of energy. It can be used to generate energy through the pyrolysis and co-pyrolysis process. The generated liquid and gas yield in the pyrolysis and co-pyrolysis method can be used with conventional fuel. However, due to higher dissolved oxygen in pyrolytic oil produced in the pyrolysis process, they are required to be improved or upgraded that makes the process complex and costly. Therefore, the co-pyrolysis process is used that can generate better quality and, upgraded liquid and gas yield. The co-pyrolysis process requires a lower reactor temperature than the pyrolysis process. In this study, co-pyrolysis of rice straw with water hyacinth and pinewood with waste plastic feedstock materials have been analyzed. It is seen that with the increase of pyrolysis reactor temperature, the liquid yield (pyrolytic oil) production also increases. However, if the reactor temperature exceeds 400 °C then the generation of liquid yield decreases. On the other hand, the generation of solid (charcoal), liquid (pyrolytic oil), and gas yield depend on the proportion of feedstock biomasses in the co-pyrolysis process. The calorific value of product yield in the co-pyrolysis process is higher than the pyrolysis process and comparable with conventional fuel, such as diesel. Therefore, the biomass co-pyrolysis process would be a potential source of bio-renewable energy that can fulfill the global energy demand with conventional fuel.

## **Acknowledgements**

Authors would like to acknowledge the department of Mechanical Engineering, Rajshahi University of Engineering & Technology, Bangladesh for the support of accessing the laboratory facilities to study the pyrolysis and co-pyrolysis process.

## **Author details**

Md. Emdadul Hoque\* and Fazlur Rashid Department of Mechanical Engineering, Rajshahi University of Engineering and Technology, Rajshahi, Bangladesh

\*Address all correspondence to: emdadulhoque@gmail.com

© 2021 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.

**79**

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

> [8] Key world energy statistics. 2007: International Energy

[9] Abnisa, F. and W.M.A.W. Daud, A review on co-pyrolysis of biomass: an optional technique to obtain a highgrade pyrolysis oil. Energy Conversion and Management, 2014. 87: p. 71-85.

[10] Wang, C., H. Bi, Q. Lin, X. Jiang, and C. Jiang, Co-pyrolysis of sewage sludge and rice husk by TG–FTIR–MS: Pyrolysis behavior, kinetics, and condensable/non-condensable gases characteristics. Renewable Energy,

[11] Bridgwater, A., D. Meier, and D. Radlein, An overview of fast pyrolysis of biomass. Organic geochemistry, 1999.

[12] Vitolo, S., M. Seggiani, P. Frediani, G. Ambrosini, and L. Politi, Catalytic upgrading of pyrolytic oils to fuel over different zeolites. Fuel, 1999. 78(10): p.

[13] Guillain, M., K. Fairouz, S.R. Mar, F. Monique, and L. Jacques, Attrition-free pyrolysis to produce bio-oil and char. Bioresource technology, 2009. 100(23):

[14] Oasmaa, A. and S. Czernik, Fuel oil quality of biomass pyrolysis oils state of the art for the end users. Energy &

[15] Parihar, M., M. Kamil, H. Goyal, A. Gupta, and A. Bhatnagar, An experimental study on pyrolysis of biomass. Process Safety and

Environmental Protection, 2007. 85(5):

[16] Zhang, Q., J. Chang, T. Wang, and Y. Xu, Review of biomass pyrolysis oil properties and upgrading research. Energy conversion and management,

Fuels, 1999. 13(4): p. 914-921.

2020. 160: p. 1048-1066.

30(12): p. 1479-1493.

1147-1159.

p. 6069-6075.

p. 458-465.

2007. 48(1): p. 87-92.

Agency Paris.

[1] Shafiee, S. and E. Topal, When will fossil fuel reserves be diminished? Energy policy, 2009. 37(1): p. 181-189.

[2] Hoque, M.E., Rashid, F., M. Prodhan, and A. Arman. Analysis of Energy Consumption and Efficiency to Reduce Power Losses in Industrial Equipment.

[3] Hoque, M. E., Biswas, A., Rashid, F., Saad, A.M., and Bir, P.K., production of elcetricity from renewable energy sources for home appliances and nanogrid, in Proceedings of the International Conference on Mechanical Engineering and Renewable Energy, 26-29 November

[4] Rashid, F., Hoque, M.E., K. Peash, and F. Faisal, performance analysis and investigation for the development of energy efficient building, in Proceedings of the International Conference on Mechanical Engineering and Renewable Energy, 18-20 December 2017, CUET,

[5] Agarwal, A.K., Biofuels (alcohols and biodiesel) applications as fuels for internal combustion engines. Progress in energy and combustion science, 2007.

[6] Manzano-Agugliaro, F., A. Alcayde, F.G. Montoya, A. Zapata-Sierra, and C. Gil, Scientific production of renewable energies worldwide: An overview. Renewable and Sustainable Energy Reviews, 2013. 18: p. 134-143.

[7] Uddin, M.S., Islam M.S., Rashid F., I.M. Habibulla, and N. Haque, Energy and Carbon Footprint Analysis of University Vehicles in Bangladesh, in Proceedings of the International Conference on Mechanical, Industrial and Materials Engineering, 28-30 December 2017, RUET, Bangladesh.

in International Conference on Mechanical Engineering, BUET, 18-20

December, 2017, Bangladesh.

2015, CUET, Bangladesh.

Bangladesh.

33(3): p. 233-271.

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*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

## **References**

*Gasification*

**78**

**Author details**

Md. Emdadul Hoque\* and Fazlur Rashid

provided the original work is properly cited.

\*Address all correspondence to: emdadulhoque@gmail.com

Technology, Rajshahi, Bangladesh

Department of Mechanical Engineering, Rajshahi University of Engineering and

© 2021 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, [1] Shafiee, S. and E. Topal, When will fossil fuel reserves be diminished? Energy policy, 2009. 37(1): p. 181-189.

[2] Hoque, M.E., Rashid, F., M. Prodhan, and A. Arman. Analysis of Energy Consumption and Efficiency to Reduce Power Losses in Industrial Equipment. in International Conference on Mechanical Engineering, BUET, 18-20 December, 2017, Bangladesh.

[3] Hoque, M. E., Biswas, A., Rashid, F., Saad, A.M., and Bir, P.K., production of elcetricity from renewable energy sources for home appliances and nanogrid, in Proceedings of the International Conference on Mechanical Engineering and Renewable Energy, 26-29 November 2015, CUET, Bangladesh.

[4] Rashid, F., Hoque, M.E., K. Peash, and F. Faisal, performance analysis and investigation for the development of energy efficient building, in Proceedings of the International Conference on Mechanical Engineering and Renewable Energy, 18-20 December 2017, CUET, Bangladesh.

[5] Agarwal, A.K., Biofuels (alcohols and biodiesel) applications as fuels for internal combustion engines. Progress in energy and combustion science, 2007. 33(3): p. 233-271.

[6] Manzano-Agugliaro, F., A. Alcayde, F.G. Montoya, A. Zapata-Sierra, and C. Gil, Scientific production of renewable energies worldwide: An overview. Renewable and Sustainable Energy Reviews, 2013. 18: p. 134-143.

[7] Uddin, M.S., Islam M.S., Rashid F., I.M. Habibulla, and N. Haque, Energy and Carbon Footprint Analysis of University Vehicles in Bangladesh, in Proceedings of the International Conference on Mechanical, Industrial and Materials Engineering, 28-30 December 2017, RUET, Bangladesh.

[8] Key world energy statistics. 2007: International Energy Agency Paris.

[9] Abnisa, F. and W.M.A.W. Daud, A review on co-pyrolysis of biomass: an optional technique to obtain a highgrade pyrolysis oil. Energy Conversion and Management, 2014. 87: p. 71-85.

[10] Wang, C., H. Bi, Q. Lin, X. Jiang, and C. Jiang, Co-pyrolysis of sewage sludge and rice husk by TG–FTIR–MS: Pyrolysis behavior, kinetics, and condensable/non-condensable gases characteristics. Renewable Energy, 2020. 160: p. 1048-1066.

[11] Bridgwater, A., D. Meier, and D. Radlein, An overview of fast pyrolysis of biomass. Organic geochemistry, 1999. 30(12): p. 1479-1493.

[12] Vitolo, S., M. Seggiani, P. Frediani, G. Ambrosini, and L. Politi, Catalytic upgrading of pyrolytic oils to fuel over different zeolites. Fuel, 1999. 78(10): p. 1147-1159.

[13] Guillain, M., K. Fairouz, S.R. Mar, F. Monique, and L. Jacques, Attrition-free pyrolysis to produce bio-oil and char. Bioresource technology, 2009. 100(23): p. 6069-6075.

[14] Oasmaa, A. and S. Czernik, Fuel oil quality of biomass pyrolysis oils state of the art for the end users. Energy & Fuels, 1999. 13(4): p. 914-921.

[15] Parihar, M., M. Kamil, H. Goyal, A. Gupta, and A. Bhatnagar, An experimental study on pyrolysis of biomass. Process Safety and Environmental Protection, 2007. 85(5): p. 458-465.

[16] Zhang, Q., J. Chang, T. Wang, and Y. Xu, Review of biomass pyrolysis oil properties and upgrading research. Energy conversion and management, 2007. 48(1): p. 87-92.

[17] Pourkarimi, S., A. Hallajisani, A. Alizadehdakhel, and A. Nouralishahi, Biofuel production through microand macroalgae pyrolysis–a review of pyrolysis methods and process parameters. Journal of Analytical and Applied Pyrolysis, 2019. 142: p. 104599.

[18] Demirbas, A., Effects of temperature and particle size on biochar yield from pyrolysis of agricultural residues. Journal of analytical and applied pyrolysis, 2004. 72(2): p. 243-248.

[19] Uzoejinwa, B.B., X. He, S. Wang, A.E.-F. Abomohra, Y. Hu, and Q. Wang, Co-pyrolysis of biomass and waste plastics as a thermochemical conversion technology for high-grade biofuel production: Recent progress and future directions elsewhere worldwide. Energy conversion and management, 2018. 163: p. 468-492.

[20] Sharypov, V., N. Marin, N. Beregovtsova, S. Baryshnikov, B. Kuznetsov, V. Cebolla, and J. Weber, Co-pyrolysis of wood biomass and synthetic polymer mixtures. Part I: influence of experimental conditions on the evolution of solids, liquids and gases. Journal of analytical and applied pyrolysis, 2002. 64(1): p. 15-28.

[21] Sharypov, V., N. Beregovtsova, B. Kuznetsov, L. Membrado, V. Cebolla, N. Marin, and J. Weber, Co-pyrolysis of wood biomass and synthetic polymers mixtures. Part III: Characterisation of heavy products. Journal of analytical and applied pyrolysis, 2003. 67(2): p. 325-340.

[22] Mahari, W.A.W., C.T. Chong, W.H. Lam, T.N.S.T. Anuar, N.L. Ma, M.D. Ibrahim, and S.S. Lam, Microwave co-pyrolysis of waste polyolefins and waste cooking oil: influence of N2 atmosphere versus vacuum environment. Energy Conversion and Management, 2018. 171: p. 1292-1301.

[23] Mourshed, M., M.H. Masud, F. Rashid, and M.U.H. Joardder, Towards the effective plastic waste management in Bangladesh: a review. Environmental Science and Pollution Research, 2017. 24(35): p. 27021-27046.

[24] Gates, B.C., G.W. Huber, C.L. Marshall, P.N. Ross, J. Siirola, and Y. Wang, Catalysts for emerging energy applications. MRS bulletin, 2008. 33(4): p. 429-435.

[25] Sonobe, T., N. Worasuwannarak, and S. Pipatmanomai, Synergies in co-pyrolysis of Thai lignite and corncob. Fuel processing technology, 2008. 89(12): p. 1371-1378.

[26] Blesa, M., J. Miranda, R. Moliner, M. Izquierdo, and J. Palacios, Lowtemperature co-pyrolysis of a low-rank coal and biomass to prepare smokeless fuel briquettes. Journal of Analytical and Applied Pyrolysis, 2003. 70(2): p. 665-677.

[27] Yuan, S., X.-l. Chen, W.-f. Li, H.-f. Liu, and F.-c. Wang, Nitrogen conversion under rapid pyrolysis of two types of aquatic biomass and corresponding blends with coal. Bioresource technology, 2011. 102(21): p. 10124-10130.

[28] Anoop, E., V. Ajayghosh, J. Nijil, and C. Jijeesh, Evaluation of pulp wood quality of selected tropical pines raised in the high ranges of Idukki District, Kerala. Journal of Tropical Agriculture, 2014. 52(1): p. 59-66.

[29] Mukaratirwa-Muchanyereyi, N., J. Kugara, and M.F. Zaranyika, Surface composition and surface properties of water hyacinth (*Eichhornia crassipes*) root biomass: Effect of mineral acid and organic solvent treatment. African Journal of Biotechnology, 2016. 15(21): p. 891-896.

[30] Soetaredjo, F.E., Y.-H. Ju, and S. Ismadji, conversion of water hyacinth

**81**

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

> [39] Onay, Ö., E. Bayram, and Ö.M. Koçkar, Copyrolysis of seyitömer− lignite and safflower seed: influence of the blending ratio and pyrolysis temperature on product yields and oil characterization. Energy & fuels, 2007.

[40] Fei, J., J. Zhang, F. Wang, and J. Wang, Synergistic effects on

[41] Martínez, J.D., A. Veses, A.M. Mastral, R. Murillo, M.V. Navarro, N. Puy, A. Artigues, J. Bartrolí, and T. García, Co-pyrolysis of biomass with waste tyres: Upgrading of liquid biofuel. Fuel Processing Technology, 2014.

[42] Jin, X., N. Chen-yang, Z. Deng-yin, G. Yan-hui, H. Qi-min, and X. Yu-hong, Co-pyrolysis of rice straw and water hyacinth: Characterization of products, yields and biomass interaction effect. Biomass and Bioenergy, 2019. 127:

[43] Nwokolo, N., S. Mamphweli, and G. Makaka, Analytical and thermal evaluation of carbon particles recovered at the cyclone of a downdraft biomass gasification system. Sustainability, 2017.

[44] Yao, D., H. Yang, H. Chen, and P.T. Williams, Co-precipitation,

[45] Bernardo, M., N. Lapa, M. Gonçalves, B. Mendes, F. Pinto, I. Fonseca, and H. Lopes, Physicochemical properties of chars obtained in the co-pyrolysis of waste mixtures. Journal of Hazardous Materials, 2012.

impregnation and so-gel preparation of Ni catalysts for pyrolysis-catalytic steam reforming of waste plastics. Applied Catalysis B: Environmental, 2018. 239:

co-pyrolysis of lignite and high-sulfur swelling coal. Journal of Analytical and Applied Pyrolysis, 2012. 95: p. 61-67.

21(5): p. 3049-3056.

119: p. 263-271.

p. 105281.

9(4): p. 645.

p. 565-577.

219: p. 196-202.

*Eichhornia crassipes* into biofuel intermediate: combination subcritical water and zeolite based catalyst processes, special issue, Renewable

[31] Shawky, B.T., M.G. Mahmoud, E.A. Ghazy, M.M. Asker, and G.S. Ibrahim, Enzymatic hydrolysis of rice straw and corn stalks for monosugars production. Journal of Genetic Engineering and Biotechnology, 2011. 9(1): p. 59-63.

[32] Yang, J., Y.C. Ching, and C.H. Chuah, Applications of lignocellulosic fibers and lignin in bioplastics: A review.

[33] Aboyade, A.O., M. Carrier, E.L. Meyer, H. Knoetze, and J.F. Görgens, Slow and pressurized co-pyrolysis of coal and agricultural residues. Energy Conversion and Management, 2013. 65:

[34] Quan, C., S. Xu, Y. An, and X. Liu, Co-pyrolysis of biomass and coal blend by TG and in a free fall reactor. Journal of Thermal Analysis and Calorimetry,

[35] Zhang, L., S. Xu, W. Zhao, and S. Liu, Co-pyrolysis of biomass and coal in a free fall reactor. Fuel, 2007. 86(3): p.

[36] Yuan, S., Z.-j. Zhou, J. Li, X.-l. Chen, and F.-c. Wang, HCN and NH3 released from biomass and soybean cake under rapid pyrolysis. Energy & fuels,

[37] Demirbas, A., Pyrolysis of ground beech wood in irregular heating rate conditions. Journal of Analytical and Applied Pyrolysis, 2005. 73(1): p. 39-43.

[38] Park, D.K., S.D. Kim, S.H. Lee, and J.G. Lee, Co-pyrolysis characteristics of sawdust and coal blend in TGA and a fixed bed reactor. Bioresource technology, 2010. 101(15): p. 6151-6156.

2010. 24(11): p. 6166-6171.

2014. 117(2): p. 817-823.

Polymers, 2019. 11(5): p. 751.

p. 198-207.

353-359.

energy, 64-69, 2016

*Co-Pyrolysis of Biomass Solid Waste and Aquatic Plants DOI: http://dx.doi.org/10.5772/intechopen.96228*

*Eichhornia crassipes* into biofuel intermediate: combination subcritical water and zeolite based catalyst processes, special issue, Renewable energy, 64-69, 2016

*Gasification*

243-248.

p. 468-492.

[17] Pourkarimi, S., A. Hallajisani, A. Alizadehdakhel, and A. Nouralishahi, Biofuel production through microand macroalgae pyrolysis–a review of pyrolysis methods and process parameters. Journal of Analytical and Applied Pyrolysis, 2019. 142: p. 104599. [23] Mourshed, M., M.H. Masud, F. Rashid, and M.U.H. Joardder, Towards the effective plastic waste management in Bangladesh: a review. Environmental Science and Pollution Research, 2017.

[24] Gates, B.C., G.W. Huber, C.L. Marshall, P.N. Ross, J. Siirola, and Y. Wang, Catalysts for emerging energy applications. MRS bulletin, 2008. 33(4):

[25] Sonobe, T., N. Worasuwannarak, and S. Pipatmanomai, Synergies in co-pyrolysis of Thai lignite and corncob. Fuel processing technology, 2008.

[26] Blesa, M., J. Miranda, R. Moliner, M. Izquierdo, and J. Palacios, Lowtemperature co-pyrolysis of a low-rank coal and biomass to prepare smokeless fuel briquettes. Journal of Analytical and Applied Pyrolysis, 2003. 70(2): p.

[27] Yuan, S., X.-l. Chen, W.-f. Li, H.-f. Liu, and F.-c. Wang, Nitrogen conversion under rapid pyrolysis of two types of aquatic biomass and corresponding blends with coal. Bioresource technology, 2011. 102(21):

[28] Anoop, E., V. Ajayghosh, J. Nijil, and C. Jijeesh, Evaluation of pulp wood quality of selected tropical pines raised in the high ranges of Idukki District, Kerala. Journal of Tropical Agriculture,

[29] Mukaratirwa-Muchanyereyi, N., J. Kugara, and M.F. Zaranyika, Surface composition and surface properties of water hyacinth (*Eichhornia crassipes*) root biomass: Effect of mineral acid and organic solvent treatment. African Journal of Biotechnology, 2016. 15(21):

[30] Soetaredjo, F.E., Y.-H. Ju, and S. Ismadji, conversion of water hyacinth

24(35): p. 27021-27046.

89(12): p. 1371-1378.

p. 429-435.

665-677.

p. 10124-10130.

2014. 52(1): p. 59-66.

p. 891-896.

[18] Demirbas, A., Effects of

temperature and particle size on biochar yield from pyrolysis of agricultural residues. Journal of analytical and applied pyrolysis, 2004. 72(2): p.

[19] Uzoejinwa, B.B., X. He, S. Wang, A.E.-F. Abomohra, Y. Hu, and Q. Wang, Co-pyrolysis of biomass and waste plastics as a thermochemical conversion technology for high-grade biofuel production: Recent progress and future directions elsewhere worldwide. Energy conversion and management, 2018. 163:

[20] Sharypov, V., N. Marin, N. Beregovtsova, S. Baryshnikov, B. Kuznetsov, V. Cebolla, and J. Weber, Co-pyrolysis of wood biomass and synthetic polymer mixtures. Part I: influence of experimental conditions on the evolution of solids, liquids and gases. Journal of analytical and applied

pyrolysis, 2002. 64(1): p. 15-28.

[21] Sharypov, V., N. Beregovtsova, B. Kuznetsov, L. Membrado, V. Cebolla, N. Marin, and J. Weber, Co-pyrolysis of wood biomass and synthetic polymers mixtures. Part III: Characterisation of heavy products. Journal of analytical and applied pyrolysis, 2003. 67(2): p.

[22] Mahari, W.A.W., C.T. Chong, W.H. Lam, T.N.S.T. Anuar, N.L. Ma, M.D. Ibrahim, and S.S. Lam, Microwave co-pyrolysis of waste polyolefins and waste cooking oil: influence of N2 atmosphere versus vacuum environment. Energy Conversion and Management, 2018. 171: p. 1292-1301.

**80**

325-340.

[31] Shawky, B.T., M.G. Mahmoud, E.A. Ghazy, M.M. Asker, and G.S. Ibrahim, Enzymatic hydrolysis of rice straw and corn stalks for monosugars production. Journal of Genetic Engineering and Biotechnology, 2011. 9(1): p. 59-63.

[32] Yang, J., Y.C. Ching, and C.H. Chuah, Applications of lignocellulosic fibers and lignin in bioplastics: A review. Polymers, 2019. 11(5): p. 751.

[33] Aboyade, A.O., M. Carrier, E.L. Meyer, H. Knoetze, and J.F. Görgens, Slow and pressurized co-pyrolysis of coal and agricultural residues. Energy Conversion and Management, 2013. 65: p. 198-207.

[34] Quan, C., S. Xu, Y. An, and X. Liu, Co-pyrolysis of biomass and coal blend by TG and in a free fall reactor. Journal of Thermal Analysis and Calorimetry, 2014. 117(2): p. 817-823.

[35] Zhang, L., S. Xu, W. Zhao, and S. Liu, Co-pyrolysis of biomass and coal in a free fall reactor. Fuel, 2007. 86(3): p. 353-359.

[36] Yuan, S., Z.-j. Zhou, J. Li, X.-l. Chen, and F.-c. Wang, HCN and NH3 released from biomass and soybean cake under rapid pyrolysis. Energy & fuels, 2010. 24(11): p. 6166-6171.

[37] Demirbas, A., Pyrolysis of ground beech wood in irregular heating rate conditions. Journal of Analytical and Applied Pyrolysis, 2005. 73(1): p. 39-43.

[38] Park, D.K., S.D. Kim, S.H. Lee, and J.G. Lee, Co-pyrolysis characteristics of sawdust and coal blend in TGA and a fixed bed reactor. Bioresource technology, 2010. 101(15): p. 6151-6156. [39] Onay, Ö., E. Bayram, and Ö.M. Koçkar, Copyrolysis of seyitömer− lignite and safflower seed: influence of the blending ratio and pyrolysis temperature on product yields and oil characterization. Energy & fuels, 2007. 21(5): p. 3049-3056.

[40] Fei, J., J. Zhang, F. Wang, and J. Wang, Synergistic effects on co-pyrolysis of lignite and high-sulfur swelling coal. Journal of Analytical and Applied Pyrolysis, 2012. 95: p. 61-67.

[41] Martínez, J.D., A. Veses, A.M. Mastral, R. Murillo, M.V. Navarro, N. Puy, A. Artigues, J. Bartrolí, and T. García, Co-pyrolysis of biomass with waste tyres: Upgrading of liquid biofuel. Fuel Processing Technology, 2014. 119: p. 263-271.

[42] Jin, X., N. Chen-yang, Z. Deng-yin, G. Yan-hui, H. Qi-min, and X. Yu-hong, Co-pyrolysis of rice straw and water hyacinth: Characterization of products, yields and biomass interaction effect. Biomass and Bioenergy, 2019. 127: p. 105281.

[43] Nwokolo, N., S. Mamphweli, and G. Makaka, Analytical and thermal evaluation of carbon particles recovered at the cyclone of a downdraft biomass gasification system. Sustainability, 2017. 9(4): p. 645.

[44] Yao, D., H. Yang, H. Chen, and P.T. Williams, Co-precipitation, impregnation and so-gel preparation of Ni catalysts for pyrolysis-catalytic steam reforming of waste plastics. Applied Catalysis B: Environmental, 2018. 239: p. 565-577.

[45] Bernardo, M., N. Lapa, M. Gonçalves, B. Mendes, F. Pinto, I. Fonseca, and H. Lopes, Physicochemical properties of chars obtained in the co-pyrolysis of waste mixtures. Journal of Hazardous Materials, 2012. 219: p. 196-202.

[46] López, A., I. De Marco, B. Caballero, M. Laresgoiti, and A. Adrados, Dechlorination of fuels in pyrolysis of PVC containing plastic wastes. Fuel Processing Technology, 2011. 92(2): p. 253-260.

[47] Paradela, F., F. Pinto, I. Gulyurtlu, I. Cabrita, and N. Lapa, Study of the co-pyrolysis of biomass and plastic wastes. Clean Technologies and Environmental Policy, 2009. 11(1): p. 115-122.

[48] Huang, L., C. Xie, J. Liu, X. Zhang, K. Chang, J. Kuo, J. Sun, W. Xie, L. Zheng, and S. Sun, Influence of catalysts on co-combustion of sewage sludge and water hyacinth blends as determined by TG-MS analysis. Bioresource technology, 2018. 247: p. 217-225.

Section 2

Gasification

**83**
