In recent years, the stoichiometry-controlled oxidation (SCO) concept has been developed by Duiker Combustion Engineers to handle the ammonia-rich streams from sulphur recovery units within refineries. These ammonia rich streams are considered as waste streams that need to be destroyed with low NOx emissions. Several full-scale commercial SCO units have already been designed, delivered, installed and put in operation on refinery sites across the world, firing pure ammonia or rich ammonia-containing flows.
The SCO technology has been based upon staged combustion and turns out to be a robust process, which is easy to operate and responds fast to upset conditions. Field test measurements on the full-scale commercial units have confirmed that NOx emission values of 50-80 ppmv (based up on 3 vol% O2 dry flue gas) can be reached, which are far below the emissions created with free ammonia combustion and without the necessity for installing a DeNOx unit.
This practically proven SCO concept is also well suited for applications in the context of ammonia as future carbon-free energy carrier. Such as but not limited to power generation and industrial (high temperature) applications. Especially the high temperature (> 1.600 °C / 2.900 °F) that can be reached in the first stage of the combustion process, makes this SCO technology attractive for industrial processes that require high temperatures, such as steel & cement industry. Also the second combustion stage in this SCO technology generates significant heat for any purpose that can use heat with a temperature from 850°C / 1560°F.
Both the high and medium temperature heat transfer possibilities that can be combined within this technology, makes this SCO technology a very important enabler for the reduction of the CO2 footprint (electrification) of our industry.
Moreover the potential in terms of CO2 reductions by the use of green produced ammonia is huge, when one considers to generate power with ammonia instead of fossil fuels as ammonia does not contain any carbon.
Duiker Combustion Engineers likes to get in contact with Companies in the field of power generation and the process industry to explore the possible applications of the SCO technology for these Companies, to reduce their Carbon footprint. As an example the sustainable multi-fuel coal fired power station has been discussed. This proposition is jointly explored with Proton Ventures.