Test your own Biochar

We have developed two simple tests so that you can see how well the biochar you have made performs. 

Water Test

You will need some Methylene Blue, which we can supply. If your biochar has been activated, it will remove all the Methylene Blue out of the water, through a process known as ‘adsorption’,

1

Crush some of your biochar into gravel-size particles.

2

Find a small jar (about 300ml) and fill it with tap water.

3

Add 1 drop of Methylene Blue 2% concentration, or two drops of Methylene Blue 1% concentration, to the jar and stir. Pour a small amount into another jar to use as a comparison at the end of your experiment.

4

Add one tablespoon of your crushed biochar to the test jar and stir. Try and avoid too much charcoal dust.

5

Leave the jar to stand for 1 hr, stirring occasionally during the first half hour only.

6

After 1 hr compare the colour of the water in the jars. If your biochar has been well activated it will have adsorbed all the Methylene Blue and the water will be colourless.

You can strain the water from your test jar through a folded sheet of kitchen roll to see just how clear it is.

Smell Test

1

Crush some of your biochar into gravel-size particles.

2

Find two glass jars the same size with sealable lids. Place a clove of peeled and sliced garlic into each.

3

Sprinkle of teaspoonful of your crushed biochar into one of the jars, then seal the lids onto both jars.

4

The biochar starts to work immediately. Leave the jars sealed for just 5 minutes and then perform a ‘sniff’ test on each. Test again after 20 minutes, again after an hour and again after a whole day. The biochar won’t eliminate the smell entirely, but the reduction should be around 80% after 24hrs.

You can perform the same test with a teaspoon of vinegar in each jar. Banana skins, see photo above, are also a good test medium.

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Carbon Farmer

Buy your own Tawi Stove to begin carbon negative cooking at your home. 

Follow us on social media for frequent updates on recipe ideas, what to do with your biochar and new ways in which to use your stove to help the planet. 

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