Chemical loop combustion uses metal oxides instead of air for fuel combustion, with offgases primarily consisting of CO2 and water vapor. Chemical ring combustion involves two interconnected reactors, with metal oxides used to oxidize fuel. This simplifies exhaust gas content, making it easier and cheaper to sequester carbon dioxide.
Chemical cycle combustion is a technique that uses metal oxides instead of air in the fuel combustion process. These systems typically use a fluidized bed to circulate metal oxides to a reaction chamber, where they provide the oxygen needed for combustion. The metal oxides are then circulated back to a different area where more oxygen can be added. Since only pure oxygen is used in the combustion process, no nitric oxide is produced. The offgases from a chemical loop combustion process typically consist primarily of carbon dioxide (CO2) and water vapour, so this method can be useful for sequestering carbon economically.
In a chemical ring combustion process, there are typically two different reactors that are interconnected in some way. One of these reactors contains fuel of some kind that requires oxygen to burn. The metal oxides are circulated, typically through a fluidized bed, in this reactor. The metal oxides are then used to oxidize the fuel. Once there is oxygen present in the fuel, it can be burned.
After the metal oxides are deprived of oxygen in the first reactor, they are circulated again in an air reactor. As the reduced metal passes into this chamber, it is exposed to air, at which point it can absorb more oxygen atoms and oxidize again. The process is then repeated, as the newly oxidized metal is circulated back into the fuel reactor and used to facilitate another burn cycle.
When any type of fuel is burned in the presence of air, numerous by-products are formed. Each of the different elements in the air and fuel can interact in many different ways, creating a variety of chemical combinations. Carbon dioxide is a major component of most exhaust gases, but due to the presence of nitrogen in the air, most combustion processes also lead to the production of nitric oxide. Oxyfuel combustion refers to a process in which oxygen is separated from the air in some way, which simplifies the chemical reactions that occur during combustion. Chemical ring combustion is a type of oxy-fuel combustion process.
The main advantage of chemical loop combustion is that the exhaust gas content can be simplified. It can be difficult and expensive to separate carbon dioxide from nitrous oxide or to sequester carbon directly from the air. The process of separating water vapor from carbon dioxide is significantly simpler, so the waste gases created by chemical loop combustion contain carbon dioxide which is less expensive to sequester.
Protect your devices with Threat Protection by NordVPN
