The BIG CHAR Continuous Carbonisation Technology (BIG CHAR CCT) was developed after a thorough review of conventional and novel thermal treatment technologies. BIG CHAR CCT is based on the material handling flexibility of the vertical multiple rotary hearth (eg. the Herreshoff hearth) and the principals of updraft gasification. It was developed to satisfy a need for cost effective conversion of waste biomass to charcoal and energy
The BIG CHAR process
The operating principle
Biomass travels from locations 1 to 5 with the assistance of a roasting wiper.
Released volatile matter is partially combusted to provide the required heat.
Off-gases are released to a second oxidation stage for conversion to clean heat.
Some of the key technical features are:
- Controlled two stage oxidation of released volatile matter, allowing efficient control of air pollutants.
- Autothermal operation (ie. no need for supplementary firing).
- Direct heat transfer, resulting in fast pyrolysis of the incoming feedstock. This means there are no heat transfer surfaces in the hearth to foul or corrode. The resulting rapid heating allow solids residence times to be as low as 60 seconds.
- Moderate and controllable temperatures in each stage. These can be optimised to minimise thermal NOx, soot and PAH formation.
- Construction that allows heating from cold to full operating temperature in under 30 minutes without damage to refractory linings or metal fittings.
- Mechanical moving bed arrangement, which provides maximum flexibility for a wide range of feedstocks, including light fluffy materials, clumping materials, chips and materials with a very diverse size range.
The unique characteristics of our technology are:
- Low investment cost compared to both conventional and novel biomass thermal treatment technologies.
- Small footprint and mass, requiring very little site preparation and minimal foundations. This is especially useful for operations that need to be relocate to follow seasonally available biomass.
- Simplicity in in design, which is a great benefit for troubleshooting and maintenance.
- Ease of maintenance. The hearth unit or the just the internals can be completely swapped out in under 6 hours, for on‑site or off-site reconditioning.
- Flexibility. BiGchar CCT systems can not only handle a wide variety of biomass feedstocks but they can be operated to bias for either carbon product or heat yield.
- Separation of the core thermal treatment step from the control of emissions. This allows the optimal processing conditions to be achieved for what are often competing needs.
- Ability to handle feedstocks that cause major fouling, slagging and/or corrosion in other technologies.
- Waste reduction, sterilisation, stabilisation and odour destruction.
- Energy from waste.
- Low cost heat supply for drying and other industrial processes.
- Production of carbons (chars) for a wide variety of end uses.
What BIG CHAR can do for you: