Location: Hawaiian Mahogany Farm Lawai on the island of Kauai in Hawai’i
Featuring: Jeff Wallin and Josiah Hunt
Five properties that make biochar valuable in agriculture:
1. A biochar partivle is porous; its high surface area allows it to capture and retain many times its weight in water.
2. It increases nutrient efficiency by attracting cations (positively charged ions, which include plant nutrients like calcium, magnesium and potassium) and anions (negatively charged ion, which include nitrates and phosphates), sharing them with the soil food web.
3. Biochar is resistant to biological and environmental decay. It can last in the soil for hundreds to thousands of years, making it an effective form of carbon sequestration.
4. Provides a secure habitat for fungi, bacteria and other microorganisms.
5. It enhances soil aeration.
How to make biochar:
1. Fast growing Albizia Trees are cut down
2. A chipper turns the timber into wood ships
3. The wood chips are shoveled into a feed conveyor
4. The conveyor maintains a constant flow of chips into the kiln
5. A kiln converts the wood chips into biochar via the process of pyrolysis [from the Greek: pyro (fire) + lysis (separatint)]. The combination of intense heat + limited oxygen makes it possible to convert organic carbon (wood) into stable carbon (biochar)
6. Steaming hot char travels out of the kiln and drops into a wheelbarrow
7. The biochar is now ready for agricultural use, either by adding it directly to the soil or mixing it with additional soil amendments.