The researchers found that pine needles, due to their flammability, pose a significant fire hazard in the coniferous forests of India’s vast sub-Himalayan belt. However, they also point out that these needles could become an abundant source of renewable energy.
According to experts from the Central Institute of Agricultural Engineering (CIAE) in India, it is important to remove fallen pine needles from forest soils. This is because during periods of drought these needles can catch fire and cause devastating forest fires. It is a preventive measure that helps maintain the safety and preservation of forests.
A study published in Current Science investigated the potential of charring and briquettes made from pine needles to reduce greenhouse gas emissions. This study analyzed how these techniques could contribute to mitigate the environmental impact.
Leading the research is Lead Scientist Sandip Mandal, Senior Scientist at CIAE’s Energy and Agricultural Energy Division in Bhopal, India, who says: “Pine needles can be easily compressed into high calorie briquettes that can be used for any thermal application or processed to produce high quality biofuel through chemical processes.“.
Pyrolysis as a method to obtain bio-oil from pine needles
Pyrolysis is a process that uses heat to convert organic matter in the absence of oxygen. Through this process, pine needles can be transformed into bio-oil, with a high calorific value of 28.52 megajoules per kilogram, and used in blended fuels for internal combustion engines or as furnace oil, according to the research.
The calorific value of diesel is approximately 45.5 megajoules per kilogram. This measurement tells us the amount of energy that diesel can generate when burned.
“The flash point, flash point and pour point values ​​of the bio-oil were higher than those of the high-speed diesel.“, reports the study, adding that the oil is also compatible with conventional compression injection engines.
An alternative way of using briquettes made from needles is in brickyards or boilers that generate energy. This provides clean, affordable fuel for cooking at home.
Pine needle briquetting process
The briquetting process consists of compressing the “lignocellulosic” biomass, obtained from dry plant matter, into compact blocks of high calorific value. These blocks are ideal for efficient storage and transport.
A study reveals that biomass is a renewable energy source superior to solar, wind and hydropower due to its wide availability. This form of energy is obtained from organic matter and offers a sustainable option to meet our energy needs.
According to the researchers, the pyrolysis of pine needles also generates biochar, an ideal material for sequestering carbon in the soil and helping to mitigate climate change. Biochar is considered an effective form of carbon sequestration that can have a positive impact in the fight against climate change.
After extensive analysis, it has been shown that the combination of all three biomass conversion technologies, such as briquetting, carbonization and pyrolysis, can achieve an impressive 87% energy efficiency. This combination offers an efficient and sustainable way to take advantage of natural resources and reduce energy consumption.
pine needle exploration
Pine needles are distinguished from other forms of plant biomass by their resistance to decomposition by microbes. This leads to them accumulating on the forest floor over time.
According to a study, it is estimated that during summer in India, around 6.3 tons of pine needles fall on every acre of pine forests.
The Himalayan subtropical pine forests stretch along the 3,000 km of the highest mountain range in the world, covering an area of ​​over 77,700 km2 in Pakistan, the Indian states of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh, as well as in Nepal and Bhutan.
Within India, the state of Himachal Pradesh stands out as an important center of research and activity related to the commercial exploitation of pine needles. With almost 3,300 square kilometers of forests full of pine trees, the state produces about 1,300 tons of needles a year.
Most forests are composed mainly of hardy species Pinus roxburghiiwhich adapts particularly well to dry conditions.
Great fire risk
According to the government of Himachal Pradesh, there are an average of 2000 wildfires in the state every year. This statistic highlights the importance of implementing effective measures to prevent and control these fires that put forests and biodiversity at risk.
Between 2001 and 2021, Himachal Pradesh lost over 900 hectares of tree cover due to fires. The most serious losses were in 2004, when 150 hectares were destroyed, according to data from the Global Forest Observation.
The Indian Institute of Technology (IIT) in Mandi, the capital of Himachal Pradesh, is leading a special program at its Uplifting Himalayan Livelihoods center to recognize the potential of pine needles as a source of renewable energy and its impact in causing wildfires. This program seeks to promote sustainable means to improve livelihoods in the Himalayan region.
“During the summer season from April to June, the fall of pine needles makes it difficult for the percolation of the water to the forest floorsays Arti Kashyap, associate professor at IIT-Mandi.
“The resulting dryness and oil content of pine needles causes them to instantly catch fire, often resulting in immense losses to biodiversity, forests, the environment and the local economy.“.
Negative impact on vegetation and local economic activities
According to Kashyap, the thick layer of pine needles can also have a negative impact on vegetation and grazing activities of local residents. This layer blocks sunlight from reaching the ground, making it difficult for the grass needed by livestock to grow.
“This leaves the villagers with no choice but to set the towers on fire.“he adds.
According to Kashyap, the IIT-Mandi program focuses on collecting pine needles and transporting them to processing centers. However, this process presents difficulties in the mountainous terrain of Himachal Pradesh.
“We believe that the installation of small pelletizing or briquetting units scattered throughout is the most viable and important option to provide local subsistence.“, it says.
Through numerous studies and research, IIT-Mandi managed to develop a method to cut and compress pine needles, obtaining clean, dense and easy-to-handle briquettes. These types of briquettes are characterized by being highly sought after as fuel due to their properties, explains Kashyap, adding that a patent application is being made.
With information from: https://www.scidev.net/