Biochar’s role in improving soil
Biochar (English: Biochar) is a type of charcoal used as a soil conditioner, which can help plants grow and can be used for agricultural purposes and carbon capture and storage. It is different from traditional charcoal that is generally used for fuel.
Biochar’s role in improving soil
Biochar (English: Biochar) is a type of charcoal used as a soil conditioner, which can help plants grow and can be used for agricultural purposes and carbon capture and storage. It is different from traditional charcoal that is generally used for fuel.
Biochar, like ordinary charcoal, is the product of thermal cracking of biomass energy raw materials, and its main component is carbon molecules. Scientists became interested in biochar because of research on Amazonian black soil. In Japan, biochar has also been used in agriculture for a long time.
In addition, using biochar can increase agricultural productivity by 20%, purify water quality, and help reduce the use of chemical fertilizers.
Pyrolysis manufacturing
People have been using charcoal as fuel for thousands of years. The manufacturing process is simple: wood, straw or crop waste are burned in an oxygen-depleted environment, and the resulting material is charcoal. The traditional method is to cover the ignited biomass with soil to allow it to burn flameless for a long time.
Large-scale industrial production of charcoal using traditional methods is impractical. Researchers have set their sights on the "pyrolysis" method - placing organic substances in an oxygen-deficient state at high temperatures of 500°C to 600°C to conduct controlled pyrolysis. In addition to obtaining charcoal, pyrolysis can also produce by-products such as syngas and liquid tar, both of which can be used as fuel for power generation or heating. The yield of biochar depends on the speed of the pyrolysis process. Rapid pyrolysis can obtain 20% biochar, 20% syngas and 60% bio-oil. Slow pyrolysis can produce 50% charcoal and a small amount of oil. The British Institute of Management and Sustainable Development believes that because modern pyrolysis plants can run entirely on syngas, the energy produced is three to nine times the required energy cost.
Biochar can increase the organic matter content of soil, improve soil structure, and improve soil water retention capacity and fertility. It can adjust the pH value, carbon-nitrogen ratio and water retention rate of the soil, thereby affecting crop growth and fruit development. Biochar can also reduce soil water evaporation, improve soil water-holding capacity, improve acidic soil, increase soil cation exchange capacity, and promote soil microbial growth.
Removal of environmental pollutants. Biochar has a large number of micropores and mesopores, a large surface area, and good adsorption capacity for organic pollutants and heavy metals. It can fix heavy metal ions through physical adsorption and chemical adsorption, and effectively remove a variety of organic pollutants.
Carbon sequestration and emission reduction. As a carbon capture, utilization, and storage technology, biochar has received increasing attention for its application in carbon sequestration and emission reduction, environmental remediation, and soil improvement. The sequestration capacity of biochar combined with the sustainable production of biomass can reduce carbon dioxide emissions in the atmosphere and have an important impact on mitigating climate change. Biomass energy utilization. Some biochar can be used to produce new clean energy sources, such as biomass pellets, biomass gas and biomass liquid fuels, thereby reducing greenhouse gas emissions.
Ways to turn waste into treasure
Many other materials can also be used to make charcoal, such as a large amount of animal and plant waste produced by agriculture - wheat straw, seed husks, dung, etc.; garbage produced by humans - such as sewage sludge or other domestic waste can be used. Using garbage waste to produce biochar also has a double carbon reduction effect. If waste manure is left to rot, it can produce methane. Methane is also a greenhouse gas, and its impact on the greenhouse effect is more than twenty times that of carbon dioxide.
The difficulty, however, is collecting this waste cost-effectively. Chris Goodell writes in "Ten Technologies to Save the Planet": "Activities such as biochar production and carbon sequestration are organized on a global scale on a large scale and farmers are paid for burying biochar in the soil. Implementation It’s a bit difficult.”
In addition, farmers also need to be equipped with new equipment to process these waste materials. For municipal waste disposal, the key is to separate organic waste that can be turned into charcoal from other waste, and to prove that doing so is more cost-effective than burying the waste.
The Institute for Management and Sustainability suggests that char can be produced using a combination of small-scale and industrial methods, and with slight improvements, biochar can be produced cost-effectively in urban, rural and even poor areas.
Making biochar is an economically feasible way to fix carbon dioxide. It not only solidifies the carbon dioxide that has been absorbed by trees and crops, but the product "biochar" is stored in the soil and will not change for thousands of years, producing renewable energy. At the same time, it also improves soil fertility and increases crop yields. Biochar can be buried in abandoned coal mines or buried in the soil during farming. Biochar landfills also help improve soil drainage systems and sequester about 80% of greenhouse gases such as nitric oxide and methane in the soil, preventing them from being released into the atmosphere.