**1. Introduction**

One problem in the rice industry is the accumulation of rice husks in high volumes, which are charred and thrown into rivers due to little interest in recycling these by-products for industrial sub-processes, thus constituting an opportunity to economically value an agricultural waste product within the value chain of paddy rice. The rice industry has a significant participation in the Peruvian economic sector, as the crop with the greatest contribution to agricultural development and GDP, producing approximately 44.7 million day wages and generating 161,300 jobs per year, representing its strong social and economic influence in rural areas. [1]. **Figure 1** shows the importance of the rice industry in Peru, which figures among the 20 countries with the highest production of paddy rice worldwide, processing a

#### **Figure 1.**

*Hectares of rice husk planted during the 2013–2014 agricultural campaign in Peru.*

total of 2200 tonnes during the 2013–2014 agricultural campaign, the second Latin American country in this agricultural sector, since most of the production of this crop is found in Asian countries [2].

At the national level, San Martín is the region with the largest paddy rice area, annually reaching 86,053 hectares in the months of July and August [3]. Within this region, a rice industry company produces 45 tonnes of paddy rice daily; therefore, there is a large supply of rice husks around the mill or in the company's growing areas, many of which are dumped into rivers or nearby roads, harming the local environment and people.

The rice husk represents 20% of total paddy rice production [4]. Approximately 9 tonnes of this agricultural waste accumulates daily [5]. Thus, rice industry companies seek opportunities to recycle these waste products, with the purpose of converting their lineal production into a circular economy, based on the economic valorization of the rice husk through the elaboration of ecological products using clean technology, which does not generate additional costs with respect to obtaining raw material.

Within the concept of a sustainable energy model, several alternatives for rice husk recycling should be analyzed, which is why it analyzed the current situation of the area, where this agricultural waste product is abundant. One of the factors with the greatest environmental impacts is the use of firewood for cooking, exacerbating local pollution, which is currently damaged by burning rice husks. Therefore, biofuels are being developed through scientific research to replace firewood. It was determined that briquettes and pellet biofuels, also known as "ecological coal," have the highest energy efficiency. Both resources have been developed worldwide for projects with similar criticality to the current situation in San Martín regarding deforestation and high firewood consumption in rural and agricultural areas.

The present case determined that the briquette is the best option to replace firewood. Unlike pellets, briquettes may be used in domestic activities, notably in individual boilers, traditional ovens, or fireplaces. These briquettes generate greater opportunities for new markets, since they can be elaborated in different forms and sizes, unlike pellets which are necessarily cylindrical and smaller [6].

**111**

to rice husk burning.

production.

*Sustainable Energy Model for the Production of Biomass Briquettes Based on Rice Husks…*

Briquette development is by no means a new technology in agricultural areas, where there are many types of biomass or resources for biofuel material. Projects with similar characteristics have already been implemented, from an environmental perspective and with a vision to maximize energy resource use. However, some did not achieve successful results, and not necessarily because of product quality but because of the way in which the proposal was developed. Others were successful but

Among the most important aspects regarding briquette proposals is the determination of raw material costs assumed by rice companies and the way in which it would impact their current budget. For example, "Corinay Briquettes" is a producer, exporter, and marketer of coal briquettes, whose initial objective was to exploit the abundance of this resource in rural areas. In addition, it would substitute domestic use of firewood, thus reducing the rate of deforestation in the region [7]. One of the main problems is the increase in the cost of coal, since "Corinay Briquettes" increased its installed capacity to 5000 tonnes per year [8], due to the large supply of briquettes that exists in rural areas, where production is concentrated. In comparison with the present proposal for briquette production under a sustainable energy model, the difference is that the rice husk will have zero costs, at

Another important aspect from other projects is the determination of different briquette production programs. For example, the company "North Wood" established different production scenarios for sawdust briquettes, focusing its business on an analysis of supply and demand, providing knowledge regarding the number of briquettes necessary to satisfy current consumption of the population using firewood in a certain area [9]. Thus, energy model sustainability will focus on the fulfillment of short- and medium-term demands so that different production scenarios may be established which respond to demand variability for this innova-

Energy model sustainability also focuses on societal acceptance and perception of briquettes. For example, the company "Eco Amazonia" did not succeed in its coconut husk briquette business because the biofuel was sold under the name of "Ecocarbón," with a coal shape and color. For this reason, society perceived that it was not an ecological product, since it was composed of charred coconut husk, which would later generate a large amount of volatile matter [10]. Therefore, the present proposal considers the inclusion of non-charred rice husks for briquette

Additionally, one of the main factors within the energy model is determining a specific place where the proposal will be developed. As mentioned above, the San Martín region is an ideal place for briquette production due to its great potential for growing rice husks coupled with high levels of firewood consumption. In this region, the sector with the highest quantity of processed rice is central Huallaga, with a total of 73,343 tonnes, divided between the provinces of Picota, Huallaga, Bellavista, and Mariscal Cáceres. However, the high volume of rice husks is not the only factor for determining the location; it is also necessary to consider environmental awareness of disadvantaged residents. For example, the municipality of San Hilarión, located in the central sector Huallaga, established Municipal Ordinance No. 013-2004/MDSH/A, which prohibits the burning of husks by mill owners. The economic sanction is valued at 2 UIT [11]. The opportunity to invest in clean technology becomes an obligation for several mills in the area; hence, they seek alternatives to recycle rice husks, economically valuing the produced biomass. **Figure 2** presents the regions with the highest rates of environmental pollution due

tive ecological product, as it may succeed based on market acceptance.

*DOI: http://dx.doi.org/10.5772/intechopen.81817*

could have had greater economic impacts.

least in the first years of operation.

#### *Sustainable Energy Model for the Production of Biomass Briquettes Based on Rice Husks… DOI: http://dx.doi.org/10.5772/intechopen.81817*

Briquette development is by no means a new technology in agricultural areas, where there are many types of biomass or resources for biofuel material. Projects with similar characteristics have already been implemented, from an environmental perspective and with a vision to maximize energy resource use. However, some did not achieve successful results, and not necessarily because of product quality but because of the way in which the proposal was developed. Others were successful but could have had greater economic impacts.

Among the most important aspects regarding briquette proposals is the determination of raw material costs assumed by rice companies and the way in which it would impact their current budget. For example, "Corinay Briquettes" is a producer, exporter, and marketer of coal briquettes, whose initial objective was to exploit the abundance of this resource in rural areas. In addition, it would substitute domestic use of firewood, thus reducing the rate of deforestation in the region [7]. One of the main problems is the increase in the cost of coal, since "Corinay Briquettes" increased its installed capacity to 5000 tonnes per year [8], due to the large supply of briquettes that exists in rural areas, where production is concentrated. In comparison with the present proposal for briquette production under a sustainable energy model, the difference is that the rice husk will have zero costs, at least in the first years of operation.

Another important aspect from other projects is the determination of different briquette production programs. For example, the company "North Wood" established different production scenarios for sawdust briquettes, focusing its business on an analysis of supply and demand, providing knowledge regarding the number of briquettes necessary to satisfy current consumption of the population using firewood in a certain area [9]. Thus, energy model sustainability will focus on the fulfillment of short- and medium-term demands so that different production scenarios may be established which respond to demand variability for this innovative ecological product, as it may succeed based on market acceptance.

Energy model sustainability also focuses on societal acceptance and perception of briquettes. For example, the company "Eco Amazonia" did not succeed in its coconut husk briquette business because the biofuel was sold under the name of "Ecocarbón," with a coal shape and color. For this reason, society perceived that it was not an ecological product, since it was composed of charred coconut husk, which would later generate a large amount of volatile matter [10]. Therefore, the present proposal considers the inclusion of non-charred rice husks for briquette production.

Additionally, one of the main factors within the energy model is determining a specific place where the proposal will be developed. As mentioned above, the San Martín region is an ideal place for briquette production due to its great potential for growing rice husks coupled with high levels of firewood consumption. In this region, the sector with the highest quantity of processed rice is central Huallaga, with a total of 73,343 tonnes, divided between the provinces of Picota, Huallaga, Bellavista, and Mariscal Cáceres. However, the high volume of rice husks is not the only factor for determining the location; it is also necessary to consider environmental awareness of disadvantaged residents. For example, the municipality of San Hilarión, located in the central sector Huallaga, established Municipal Ordinance No. 013-2004/MDSH/A, which prohibits the burning of husks by mill owners. The economic sanction is valued at 2 UIT [11]. The opportunity to invest in clean technology becomes an obligation for several mills in the area; hence, they seek alternatives to recycle rice husks, economically valuing the produced biomass. **Figure 2** presents the regions with the highest rates of environmental pollution due to rice husk burning.

*Green Energy Advances*

crop is found in Asian countries [2].

environment and people.

raw material.

**Figure 1.**

total of 2200 tonnes during the 2013–2014 agricultural campaign, the second Latin American country in this agricultural sector, since most of the production of this

*Hectares of rice husk planted during the 2013–2014 agricultural campaign in Peru.*

At the national level, San Martín is the region with the largest paddy rice area, annually reaching 86,053 hectares in the months of July and August [3]. Within this region, a rice industry company produces 45 tonnes of paddy rice daily; therefore, there is a large supply of rice husks around the mill or in the company's growing areas, many of which are dumped into rivers or nearby roads, harming the local

The rice husk represents 20% of total paddy rice production [4]. Approximately

Within the concept of a sustainable energy model, several alternatives for rice husk recycling should be analyzed, which is why it analyzed the current situation of the area, where this agricultural waste product is abundant. One of the factors with the greatest environmental impacts is the use of firewood for cooking, exacerbating local pollution, which is currently damaged by burning rice husks. Therefore, biofuels are being developed through scientific research to replace firewood. It was determined that briquettes and pellet biofuels, also known as "ecological coal," have the highest energy efficiency. Both resources have been developed worldwide for projects with similar criticality to the current situation in San Martín regarding deforestation and high firewood consumption in rural and agricultural areas. The present case determined that the briquette is the best option to replace firewood. Unlike pellets, briquettes may be used in domestic activities, notably in individual boilers, traditional ovens, or fireplaces. These briquettes generate greater opportunities for new markets, since they can be elaborated in different forms and

9 tonnes of this agricultural waste accumulates daily [5]. Thus, rice industry companies seek opportunities to recycle these waste products, with the purpose of converting their lineal production into a circular economy, based on the economic valorization of the rice husk through the elaboration of ecological products using clean technology, which does not generate additional costs with respect to obtaining

sizes, unlike pellets which are necessarily cylindrical and smaller [6].

**110**

**Figure 2.** *Environmental pollution due to rice husk burning during 2013–2014 agricultural campaign in Peru.*

**Figure 3.** *Dimensions of rice husk briquettes.*

As mentioned above, the briquette is not a new technology, so determining briquette design will depend on product use and specifications of the briquette machine. For industrial processes or businesses, lengths vary between 300 and 1000 mm, for producers length varies between 100 and 500 mm, and for domestic sector, length varies between 30 and 80 mm. **Figure 3** shows the ideal prototype of briquettes for domestic use.

The inclusion of an interior hole will endow the briquette with greater oxygenation capacity but could increase volatile matter, so the shape of the product will depend directly on its use, be it industrial or domestic. Another variable is the market approach to briquette production, since it will not necessarily be used as fuel but can also act as a heating resource in locations with low temperatures or may be exported to the European market. Density is another main characteristic, since as it becomes denser; less volume will be occupied, which will mean easier handling, optimum storage, and easier transport, compared to firewood. Its weight should be 1000 kg/m3 [12], and this depends mainly on rice husk density and the pressure exerted by briquette machines. Finally, humidity directly influences heating capacity, for they contain a large percentage of moisture and the energy released is lower during combustion, causing evaporation to consume heat. Humidity should vary between 8 and 10% [13].
