Auto-thermal Cracking - Technology
Many technical challenges have been addressed during the development of autothermal cracking
- Mixing fuel and pure oxygen over a wide range of pressures to achieve good mixing with minimum inventories, and deliver mixed feeds uniformly to the catalyst
- Catalyst design to ensure mechanical robustness and chemical stability
- Designing a commercial scale reactor which can safely handle the mechanical challenges of fast heating and cooling at pressures up to 30 barg
- Rapid gas phase quenching, to avoid secondary products and boost olefin yields
- Product purification, including detailed quench tower design
Ethylene and propylene can be made from a wide range of feedstocks using autothermal cracking. We have experience of all feeds from vacuum residue to ethane. Lighter feeds allow access to elevated pressure operation.
Cracking severity can be controlled over a wide range, as can ethylene to propylene product ratio.
Autothermal cracking gives impressive emissions benefits. The process is not air-fed, and reaction temperatures are well below the flame temperatures of steam cracker furnaces, so NOx is almost completely eliminated. Greenhouse gas footprint is also reduced by up to 40% owing to a lower energy demand.
In contrast to steam cracking, unsaturated hydrocarbon streams may be fed to the autothermal reactor without pre-treatment, and without coke formation problems. This allows a wide range of low cost recycle stream options to be considered with an autothermal cracker.
