Midrex has developed a new concept, employing a CO₂ removal system that allows for even lower emissions. This option uses an amine-type system that removes CO₂ from the top gas. This stream is then preheated, with part of it added to the reformed gas, which goes to the shaft furnace. The remainder is used for top gas fuel in the reformer burners.

The advantage of this option is the flexibility it provides the plant operator, with relatively small changes in capital cost, operating consumptions, and operating costs. The use of CO₂ removal allows for higher DRI production without adding additional reformer bays, and lowers natural gas consumption, in addition to the benefits of lower CO₂ emissions.