Bring Carbon Back Into Ground

Bring carbon back into ground and improve your gardens soil.

Climate change is undeniable. Since the beginning of industrialization, the average temperatures on our planet have risen measurably. The consequences are not only higher temperatures alone, but also a more chaotic course of weather phenomena.

In short, the cause is the carbon that we put into the atmosphere as CO₂. For millions of years, plants have used CO₂ from the air through photosynthesis to build their structures (wood). Many tropical forests were covered over, and the pressure and exclusion of air turned the wood into coal, oil and natural gas, sealing it into the ground for millions of years.

It was only mankind that liberated the carbon, used it for its own purposes, made a profit from it, burned it and released it into the atmosphere.

There are efforts to capture CO₂ by technical means and press it into deep caves. But apart from stopping climate change, this has no benefit for the individual, no direct profit. That's why very few countries will be able to afford such measures, let's not even talk about political will. The motivation is low.

CO₂ binding must therefore be profitable. The liberation of carbon was also lucrative.

Reforestation? With pleasure! But after 60-100 years the tree decays back into its component parts and most of the carbon is released back into the atmosphere.

Wild method:

Fire pit, shovel, tub of water.

Technical method:

2 metal barrels from the scrap yard (one must fit into the other)

chimney pipe (1.5 meter)

Here is the solution:

CO₂ can be brought into the soil as (wood) charcoal without complicated technical aids. A piece of charcoal acts like a sponge that can absorb water and nutrients and provide a habitat for countless microbes thanks to its enormous surface area. The surface of a single piece of coal can be the size of half a football pitch.

The principle is not new; it was practiced a long time ago by the indigenous peoples of South America in the form of “Terra Preta”.

Where does the coal come from?

Producing charcoal separately means little profit or high costs. We don't want to use our charcoal as barbecue charcoal. Our charcoal must therefore be a by-product.

Do not buy barbecue charcoal! That would be a waste of valuable wood. Only use dry waste materials.

As I proved in experiments back in 2014, not only waste wood, but also hay, coconut shells, bamboo and apricot kernels can be carbonized by pyrolysis. The important thing is that the material is reasonably dry.

In my area I am allowed to burn garden waste outside a village if there is no risk of forest fire. You mean burning wood is bad? Well, but if I leave the waste wood to rot, the CO₂ is still released into the atmosphere, just a little later. However, I don't let the branches and twigs burn completely, but use a shovel to

1. take the glowing coals out of the fire,
2. put them in a tub of water to cool down,
3. leave them there for a few minutes,
4. and then take them out again and pile them up.

In this way, I can preserve a great part of the wood for further use.

In my area, many farmers have a wood chip heating system. It is imaginable that some of the heat for the pyrolysis process could be used to produce coal from the same material (wood chips). Put simply, you only need heat and the absence of air to carbonise material.

Pyrolysis Oven

You will need only a few tools to make a pyrolytic oven: hammer, pointed chisel and tin scissors. I assume that the barrels are open and empty. Only the large barrel needs a lid.

We make air holes all round the bottom of the side wall of the large barrel using the pointed chisel. Find the centre of the lid and mark the future opening with the stovepipe. Starting from the centre of the circle, cut to the edge of the circle and bend the metal strips upwards. We can then place our stovepipe on this corona. This is important to create the necessary chimney effect and draught in our stove. It also keeps the smoke away from you.

Now we fill the small barrel tightly with the material to be carbonised: wood, hay, straw, nutshells, bamboo, bark, etc.

We place this small barrel with the opening facing downwards into the large barrel. The space in between both barrels is now filled tightly with wood. Firewood is also placed on the small barrel, which is then lit. Once the fire is strong enough, the lid with the chimney is placed on top. It now takes about three hours for the wood to burn and for the heat to char our material. No further work needed, just wait.

The outer fire provides the heat for the process. The inner barrel does not get any oxygen, so burning does not take place. However, the heat causes the material to gas out, carbon monoxide escapes and in turn feeds the outer fire.

When no more smoke is emitted, allow the barrel to cool slightly and open it.

Years ago I used small cans and a metal hoover tube to make charcoal for art lessons :-)

I have been adding the charcoal to my compost heap for years, where it stores nutrients and improves the soil. A little nettle manure or sheep manure from my neighbor's barn also helps with the rotting process.

Even years later, the smallest pieces of coal can still be found in the fertile soil of my vegetable garden. The carbon is thus stored in a permanently useful way and the soil is improved. So my work benefits me AND the climate.

If you're interested, check out my simple presentation on Terra Preta as pdf from 2014 (in German).

How can this be applied on a large scale? By the farmers! They already have to do a lot: grow food, maintain the landscape, look after animal welfare,... Often the profits are small. Why should they have to do this work as well?

Suggestion:

There is a lively trade in CO₂ certificates: Anyone who blows CO2 into the atmosphere has to pay for it. Why not pay farmers when they put carbon back into the soil? It could be profitble for them. They have the best prerequisites:

1. wood chip heating systems are often already available and can be easily upgraded
2. organic waste material
3. suitable heavy machinery
4. fields for spreading the carbon
5. Improving the soil: instead of just harvesting for decades and removing material from the soil, useful mass is added
6. the coal serves as a fertiliser reservoir and reduces the harmful effects of liquid manure on soil and groundwater.
7. prevents soil degradation

From a technical point of view, it would not be difficult to upgrade wood chip heating and install a container for the material to be carbonised next to the firing boiler, together with a gravity using transport system.

In any case, I continue with my charcoal. My gain is the improvement of my soil and the good feeling of contributing at least a tiny part to saving the climate as an individual.

Save this planet - bring carbon back into ground today!