What Is Biochar And How It Is Produced And Used

Biochar can be a rewarding and environmentally friendly. It is a type of charcoal produced by pyrolysis, which is the process of heating biomass in the absence of oxygen. This guide will take you through the steps of producing biochar using various methods, its benefits, its uses and safety considerations.

What is Biochar?

In simple words, biochar is a type of charcoal made from burning organic materials like wood, agricultural waste, or plant debris in a special way. It is produced through a process called pyrolysis, where these materials are heated without much oxygen. As a result, the organic matter doesn’t burn completely but instead turns into a black, porous, and stable substance known as biochar.

It has a unique structure with lots of tiny holes, which makes it great at storing water and nutrients. When added to soil, biochar helps plants grow better because it acts like a sponge, holding onto water and essential nutrients, and making them available to plants when needed. It also stays in the soil for a long time, which means it can help store carbon and improve soil quality for many years.

It is considered beneficial for the environment because it can help reduce greenhouse gases in the atmosphere and improve soil health, making it a useful tool in fighting climate change and promoting sustainable agriculture.

Uses of Biochar

Biochar has a wide range of applications due to its unique properties and benefits. Some of the common and beneficial uses of biochar include:

  1. Soil Amendment: One of the primary uses of it is as a soil amendment. When mixed into the soil, it improves soil structure, enhances water retention, and promotes nutrient retention. It creates a better environment for beneficial microorganisms, leading to healthier and more productive soils for agriculture and gardening.
  2. Carbon Sequestration: It is a stable form of carbon that can remain in the soil for hundreds or even thousands of years. By incorporating biochar into the soil, it helps sequester carbon, reducing greenhouse gas emissions and mitigating climate change.
  3. Waste Management: Its production can help recycle organic waste that might otherwise end up in landfills or contribute to air pollution through open burning. By converting this waste into biochar, valuable carbon is stored in a beneficial form while reducing waste volumes.
  4. Water Filtration: It’s porous structure makes it an effective material for filtering contaminants from water. It can be used in water treatment systems to remove impurities and pollutants, improving water quality.
  5. Livestock Feed Additive: Some research suggests that biochar can be used as an additive in livestock feed to improve digestion and reduce methane emissions from animals.
  6. Composting Enhancer: Adding biochar to compost piles can accelerate the composting process and improve the quality of the compost by enhancing nutrient retention.
  7. Aquaponics and Hydroponics: It can be used as a growing medium in aquaponics and hydroponics systems, providing a stable substrate for plant roots and enhancing nutrient availability.
  8. Remediation of Contaminated Soils: Biochar has shown promise in remediating contaminated soils by immobilizing and reducing the availability of certain pollutants.
  9. Building Material: In some cases, it is mixed with other materials like clay or cement to create sustainable building materials with improved insulation properties.
  10. Livestock Bedding: It can be used as bedding material for livestock, offering improved moisture retention and reduced odors.

It’s important to note that the effectiveness of biochar can vary based on its production method, the type of feedstock used, and the specific application. Proper testing and evaluation should be done to determine the appropriate use of it in different scenarios. Additionally, it should be used responsibly, considering the specific needs of the environment and agricultural practices, to ensure it provides the desired benefits.

What You’ll Need:

  1. Biomass: Any organic material can be used as biomass, such as wood chips, sawdust, agricultural waste, nut shells, or even yard waste like leaves and branches.
  2. Container: You’ll need a metal or ceramic container with a lid to ensure proper heating and prevent oxygen from entering during the pyrolysis process. A metal drum or a custom-made biochar kiln will work well.
  3. Air Supply: For larger kilns, you might need a way to control the air supply during the pyrolysis process. This can be achieved using vents or holes in the container.
  4. Heat Source: You’ll need a heat source to initiate the pyrolysis process. Common options include a campfire, a wood stove, or even a gas burner.
  5. Thermometer: A thermometer will help you monitor the temperature during the pyrolysis process and ensure that it remains within the optimal range.
  6. Safety Gear: Wear gloves, a mask, and eye protection when handling the biochar and during the pyrolysis process.

Step-by-Step Process:

  1. Prepare the Biomass: Cut or break down the biomass into small pieces. For larger pieces like branches, consider using a wood chipper or a shredder to get smaller-sized materials.
  2. Choose a Location: Find a suitable outdoor location to perform the process. Ensure that it’s well-ventilated and away from flammable materials.
  3. Build the Kiln: If you’re using a metal drum, make sure it has a tight-fitting lid. If not, construct a simple kiln using bricks or other heat-resistant materials.
  4. Load the Kiln: Place the biomass inside the kiln, leaving enough space for air to flow between the pieces. Avoid tightly packing the biomass, as it may impede the pyrolysis process.
  5. Start the Pyrolysis Process: Ignite the heat source and place it under the kiln. Close the lid tightly to minimize oxygen intake. If your kiln has vents, adjust them to control the airflow and regulate the temperature. The pyrolysis process typically occurs between 400°C to 600°C (752°F to 1112°F).
  6. Monitor the Temperature: Use a thermometer to keep track of the internal temperature of the kiln. If it gets too hot, adjust the airflow to cool it down, and if it’s too cold, increase the airflow or add more heat.
  7. Wait for Completion: The pyrolysis process can take several hours to complete, depending on the size of the kiln and the type of biomass used. You’ll know it’s finished when the smoke coming out of the kiln turns from white or gray to thin and bluish.
  8. Cool Down: Once the pyrolysis process is complete, turn off the heat source and let the kiln cool down. Do not open the lid until it’s safe to touch. The biochar should be cool to the touch before handling.
  9. Store the Biochar: Store the produced biochar in a dry and airtight container. This will prevent it from absorbing moisture and losing its beneficial properties.

Safety Considerations:

  1. Fire Safety: Its production involves high temperatures, so be cautious about the risk of fire. Keep a fire extinguisher or a bucket of water nearby, just in case.
  2. Avoid Inhalation: The pyrolysis process releases smoke and harmful gases. Perform the process outdoors or in a well-ventilated area, and wear a mask to avoid inhaling the fumes.
  3. Use Protective Gear: Wear gloves, long-sleeved clothing, eye protection, and a mask to protect yourself from the heat and potential hazards.
  4. Keep Children and Pets Away: Make sure children and pets stay a safe distance from the kiln during the pyrolysis process.

Benefits of Biochar:

  1. Carbon Sequestration: It helps to store carbon in a stable form, reducing greenhouse gas emissions when produced from sustainably harvested biomass.
  2. Soil Enrichment: Adding biochar to soil can improve its fertility, water retention, and nutrient-holding capacity. It creates a favorable environment for beneficial microorganisms.
  3. Waste Reduction: Its production provides a useful way to recycle organic waste that might otherwise end up in landfills or contribute to air pollution through open burning.
  4. Ecosystem Restoration: It can be used to restore degraded soils, aiding in the reestablishment of native vegetation and promoting biodiversity.

Final Thoughts:

Producing biochar at home is an environmentally friendly way to recycle organic waste and create a valuable soil amendment. By following safety guidelines and being mindful of the pyrolysis process, you can successfully create biochar for your gardening or agricultural needs. Always remember to consult local regulations and guidelines related to biochar production and use, and consider experimenting with different biomass sources to find what works best for your specific needs.

Books to enrich your knowledge

It is an interesting and multidisciplinary subject, and there are several books that delve into its production, applications, and environmental benefits. Here are some highly regarded books on biochar that you might find informative:

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  1. The Biochar Solution: Carbon Farming and Climate Change by Albert Bates: This book explores the potential of biochar as a solution to climate change and its role in sustainable agriculture. It covers the history, science, and its practical applications, making it a comprehensive read for anyone interested in the topic.
  2. Biochar for Environmental Management: Science, Technology, and Implementation edited by Johannes Lehmann and Stephen Joseph: This book provides a scientific overview of biochar and its applications in various environmental management contexts. It covers topics such as production techniques, soil improvement, carbon sequestration, and waste management.
  3. The Biochar Revolution: Transforming Agriculture & Environment edited by Paul Taylor: This book features contributions from experts in the field of biochar research and discusses the potential benefits of biochar for agriculture, soil fertility, and climate change mitigation. It also includes practical advice on how to produce and use biochar effectively.
  4. The Biochar Debate: Charcoal’s Potential to Reverse Climate Change and Build Soil Fertility by James Bruges: In this book, the author delves into the potential of biochar as a tool to combat climate change while enhancing soil fertility. It presents both the promises and challenges of biochar adoption, providing a balanced view of the subject.
  5. Biochar: A Guide to Analytical Methods edited by Joseph J. Pignatello and Johannes Lehmann: This book focuses on the analytical methods used to study biochar properties and its impact on soil and the environment. It is an essential resource for researchers and scientists interested in conducting studies related to biochar.
  6. The Biochar Solution: Carbon Farming and Climate Change by Albert Bates: Another book with a similar title but authored by Albert Bates. It explores how biochar can contribute to carbon farming and its role in mitigating climate change while promoting sustainable agricultural practices.

These books cover various aspects of biochar, from the science behind it to its practical applications in agriculture and environmental management. Depending on your specific interests and background, you may find one or more of these books to be a valuable resource for expanding your knowledge on the subject of biochar.


  1. International Biochar Initiative (IBI): https://www.biochar-international.org/
  2. U.S. Department of Agriculture (USDA) Biochar Basics: https://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/national/soils/health/mgnt/?cid=nrcs142p2_053862
  3. Biochar Journal: https://www.biochar-journal.org/
  4. Biochar for Environmental Management: Science, Technology, and Implementation (Book): https://www.routledge.com/Biochar-for-Environmental-Management-Science-Technology-and-Implementation/Lehmann-Joseph/p/book/9780415704152