This negative emissions technology uses fast pyrolysis to convert waste biomass to bio-oil, which is then pumped into the same deep underground rock formations that stored crude oil for millions of years.

Charm Industrial’s negative emissions

Our partner Charm Industrial converts waste biomass into bio-oil, which is then injected deep underground into the same underground rock formations that stored crude oil for hundreds of millions of years. We can’t put the fossil fuels we’ve burned back where we took them from, but we can get close by producing bio-oil and storing it underground.

Instead of letting waste biomass like excess sawdust and wood, sugar cane bagasse, corn stover, rice straw, or almond shells rot - which releases the stored CO₂ -, Charm makes bio-oil out of it. Bio-oil is produced by heating the biomass up to about 500°C in a few seconds witout any oxygen, this process is called fast pyrolysis.

Bio-oil is a liquid similar to crude oil except for a few characteristics making it a bad fuel but great for geological storage. It is a bad fuel because it is expensive to produce, it’s heavily oxygenated - which makes it have half of the energy content of crude oil - and it has a habit of solidifying over time in storage. The solidification over time and the high carbon content however are extremely useful for permanent storage.

Once produced, the carbon rich bio-oil is transported to an injection well, prepared for injection and pumped underground. Hence in this process CO₂ is taken from the atmosphere and formed to biomass, which is converted to bio-oil and then injected into rock formations to be stored for millions of years.

Life cycle analysis

For every ton of bio-oil the production of bio-oil emits about 0.04 tons of CO₂e, the transport emits 0.05 tons of CO₂e and the injection emits about 0.004 tons of CO₂e. A ton of bio-oil sequestered about 1.53 tons of CO₂e. This results in a net sequestration of 1.44 tons of CO₂e accross the lifecycle of bio-oil.

Impact

We at Carbon Removed think that Charm is a great young company that has an extremely clever approach with the potential to fix a great part of the harm done by replenishing the empty crude oil wells with bio-oil. Compared to other methods, the permanence of CO₂ removal with bio-oil is extremely promising as it is highly likely that the bio-oil will stay underground for milllions of years like crude oil did until humanity took it out.

There are a few environmental impacts that need to be considered, which are particulate and NOx emissions, increased road traffic and the potential for seismic activity. Particulate and NOx emissions and road traffic can be minimised by injecting the bio-oil on the same site where the biomass is processed. If the biomass has to be transported a long way for bio-oil conversion and then the bio-oil needs to be transported a long way to the injection well, this will increase particulate and NOx emissions, and road traffic.

Seismic activity is believed to be increased by lubricating the interfaces between rock layers in the injection wells - this needs further research.

This project is one of many we support - minimising the damage done to the environment and maximising the impact we can all have on climate change. It is important that everyone chooses to reduce their footprint and slow the emissions of dangerous greenhouse gases but combined with carbon removal projects such as this one, it is possible for us to fight and undo the climate crisis.

If you’re interested in supporting carbon removal projects like bio-oil, please start a subscription today and turn your emissions into trees, stone and bio-oil.