Turning waste CO2 into feedstock
CO2 capture and CO2 utilization technologies are receiving a lot of attention in the context of combating climate change. ReShift™, Topsoe’s CO2 reforming technology, offers a new way to utilize CO2 to produce tailor-made synthesis gas.
From waste product to feedstock
CO2 is a greenhouse gas generated as a waste product in many industries and is often emitted to the atmosphere. However, reforming of methane with mixtures of steam and carbon dioxide, or CO2 reforming, is a way to actually use the CO2 as feedstock to produce valuable synthesis gas. CO2 reforming, used in Topsoe’s ReShift™ technology, is a chemical process that can be designed with overall negative CO2 emissions, providing a way to convert waste CO2 to valuable products.
An increase in the amount of CO2 added to the process will result in an increased fraction of CO in the produced synthesis gas. Through CO2 reforming, synthesis gas can be produced covering a wide range of H2/CO ratios. These CO-rich gasses are typically used in the production of functional chemicals and fuels.
New high temperature reactor for production of CO-rich synthesis gas
Increasing CO2 in the feed, however, moves operating conditions closer to and even beyond the carbon formation limits for nickel -based reforming catalysts. This can be mitigated by Topsoe’s ReShift™ technology.
ReShift™ is based on a two-reactor system, where classical steam reforming is done initially in a SMR or ATR, followed by CO2 addition to the hot synthesis gas and subsequent conversion in an adiabatic post convertor (APOC).
The central element of the ReShift™ technology is that it utilizes the high temperature of the main reformer product gas to circumvent the carbon limits. This allows for operating at overall steam-to-carbon ratios of below 1.5, irrespective of overall CO2 addition - something that is not possible in a classic fired reformer. The central element of the APOC is that the temperature is kept higher than 700–800°C to circumvent the carbon limits. For grassroot plants, the ReShift™ technology allows for design of significantly more compact reformers (up to 30% reduced size), which in turn also reduces firing, and thereby CO2 emissions from the reformer.
ReShift™ technology offers a solution for producing synthesis gas with a high content of CO at a low steam-to-carbon ratio. The technology can be used to retrofit an existing unit towards more CO production or it can be included in new builds. ReShift™ is an excellent match in cases where synthesis gas with high CO-content is required and excess CO2 is available. ReShift™ is reducing overall CO2 emissions and turning waste CO2 into valuable chemicals and fuels.