Another benefit of gasification is that it outputs two usable materials. The first, clean syngas mentioned earlier. The second, a “high-carbon biochar.” In a downdraft gasification process, such as the one we deploy and developed by Aries Clean Energy, 95% of the input waste is converted into syngas. 5% becomes biochar, which can be used again. Here are just a few examples of its applications and uses:
- Fuel for kiln type operations or where a solid fuel type is required
- Filtering media in a number of industries and varied applications from liquids, gases and odours
- Growth foundation for in marine applications such as reef regeneration
- Increases water retention, thus reducing irrigation volumes
- Increases beneficial microbial activity and so crop yields whilst reducing fertiliser use, costs and resultant excess nutrient run-off
- Moderates soil acidity
- Reduces leaching of nitrogen into ground water
- Improves cation-exchange capacity
In contrast to other waste-to-energy options like incineration, downdraft gasification does not produce ash. Incineration on the other hand, produces an ash that is sometimes used to cover landfills, but must be carefully controlled to manage leaching of harmful chemicals.
Again, downdraft gasification helps close the loop on waste materials by creating a byproduct with another valuable life.