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Activated charcoal


Activated charcoal, also known as activated carbon, is a highly porous form of carbon that has been processed to increase its surface area. This increased surface area gives activated charcoal the ability to adsorb (not absorb) a wide range of substances onto its surface. In simple terms, adsorption is the process by which molecules and particles adhere to the surface of the charcoal.

Why is Activated Charcoal Used in Permaculture Farming?

  1. Water Filtration: Activated charcoal is commonly used in permaculture for water filtration. It can effectively remove impurities, toxins, and organic contaminants from water, making it safer for irrigation and other agricultural uses.
  2. Soil Amendment: Incorporating activated charcoal into the soil can improve soil structure and enhance its ability to retain water and nutrients. It also helps in reducing soil compaction, thereby promoting healthier root development.
  3. Odor and Gas Control: In compost piles or worm bins, activated charcoal can help control odors and absorb unwanted gases that may be produced during the decomposition process.
  4. Toxin and Chemical Remediation: Activated charcoal can help mitigate the impact of certain toxins and chemicals in the environment. It can be used to remove pesticides, herbicides, and heavy metals from soil and water.

How is Activated Charcoal Used in Permaculture Farming?

  1. Water Filtration System: In permaculture farms, activated charcoal can be used in water filtration systems to purify water for irrigation, livestock consumption, and other farm-related uses. It is often integrated into biofilters or slow sand filters.
  2. Compost Amendment: Adding activated charcoal to compost piles helps prevent the loss of nutrients through leaching and provides a favorable environment for beneficial microbes to thrive.
  3. Soil Improvement: Activated charcoal can be mixed into the soil or applied as a top dressing to improve soil fertility, water retention, and aeration. It is especially beneficial in areas with poor or compacted soils.
  4. Aquaponics and Hydroponics: In closed-loop aquaponics and hydroponics systems, activated charcoal can be used to maintain water quality by removing impurities and maintaining a healthy environment for the fish and plants.
  5. Livestock Management: Activated charcoal can be used as a feed additive for livestock to help reduce digestive issues and mitigate the effects of certain toxins in their diet.
  6. Air Purification: In certain cases, activated charcoal may be used to filter air in greenhouses or enclosed growing spaces to remove harmful gases and pollutants.

It’s important to note that while activated charcoal can be beneficial, it should be used judiciously and not excessively, as its adsorption properties can also remove beneficial substances from the environment. As with any permaculture practice, a holistic and sustainable approach should be followed to ensure the best results for the farm’s ecosystem.

Making activated charcoal

Making activated charcoal at home involves a simple process of heating natural materials to create a highly porous and adsorptive form of carbon. Here’s a basic method to make activated charcoal at home:

Materials Needed:

  • Natural carbon-rich material (e.g., coconut shells, wood, or bamboo)
  • Metal container or old metal pot with a lid
  • Drill or hammer and nail
  • Firewood or a heat source
  • Water

Step-by-Step Process:

  1. Prepare the Carbon-Rich Material:
  • Choose a carbon-rich material such as coconut shells, wood, or bamboo. Coconut shells are often preferred due to their high carbon content and availability.
  • Wash and clean the material to remove any dirt or debris.
  1. Create Airflow:
  • The key to creating activated charcoal is to expose the carbon-rich material to high temperatures without oxygen (anaerobic conditions). This is typically achieved by controlling the airflow during the heating process.
  • Using a drill or a hammer and nail, create small holes in the metal container’s lid to allow some airflow while preventing too much oxygen from entering.
  1. Prepare the Metal Container:
  • Place the cleaned carbon-rich material in the metal container.
  • Cover the container with the perforated lid, ensuring there is a tight fit to control the airflow.
  1. Heating the Material:
  • Place the metal container with the carbon-rich material on the firewood or heat source.
  • Start heating the container slowly to drive off volatile compounds and moisture from the material. This process is called pyrolysis.
  • Gradually increase the heat until the temperature reaches around 400 to 600°C (752 to 1112°F). The exact temperature may vary depending on the material used.
  1. Anaerobic Conditions:
  • Once the desired temperature is reached, reduce the airflow to the container as much as possible to create anaerobic conditions inside.
  • Continue heating the material under these conditions for a specific period, typically 1 to 2 hours. The duration can be adjusted based on the desired level of activation.
  1. Cooling and Quenching:
  • After the activation process, carefully remove the metal container from the heat source.
  • Allow the container to cool down naturally for a few hours.
  • Once the container has cooled, open the lid and quench the activated charcoal with water to stop the activation process.
  1. Cleaning and Drying:
  • Rinse the activated charcoal thoroughly with water to remove any residual ash or impurities.
  • Spread the activated charcoal on a clean surface and let it dry under the sun or in a well-ventilated area.

Safety Precautions:

  • The process of making activated charcoal involves high temperatures and fire, so it should be done outdoors in a well-ventilated area.
  • Use appropriate safety gear such as heat-resistant gloves and eye protection during the process.

Please note that homemade activated charcoal may not have the same purity or adsorption capacity as commercial activated charcoal. Therefore, it is essential to use caution and not rely on homemade activated charcoal for critical medical or filtration purposes.

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