The thermal design of this regenerator is the same as of other types of regenerators. Another type of regenerator is called a micro scale regenerative heat exchanger. Catalytic cracking uses reactor and a regenerator. The "Rothemuhle" regenerator is used as an air preheater in some power generating plants. Another type of air preheater is the "regenerator" used in iron or glass manufacture. The allowable pressure level of a rotary regenerator is relatively low, compared to heat exchangers. The cold head contains a compression and expansion space, a regenerator, and a displacer. Lubricants can also clog heat exchangers, especially the regenerator. Usually the regenerator and the displacer are combined in one body. The regenerator section refers to the section and photonic layers. One must also prevent oil vapor from entering the regenerator by high-quality purification traps. On its return the heat stored within the regenerator is transferred back into the gas. The stripped overhead gas from the regenerator is concentrated and . The stripped overhead gas from the regenerator is concentrated HS and CO. This is consistent with the zero-net heat transfer of the regenerator (solid green line).