Douglas Leslie Bennett

ITM Syngas ceramic membrane technology for synthesis gas production

Publisher Summary The ITM Syngas process is a breakthrough technology that combines air separation and high-temperature synthesis gas generation processes into a single ceramic membrane reactor, with significant savings in the capital cost of synthesis gas production. Because synthesis gas is a feedstock for a range of different processes, ITM Syngas represents a technology platform that has numerous applications, such as gas-to-liquids; hydrogen; clean fuels, including liquid transportation fuels; and chemicals. The basic fabrication methods used to construct ITM Syngas wafers are—tape casting, laser cutting, lamination, and co-sintering. Although these processes are each practiced commercially, the sub-surface open channels found in these wafers required the development of new lamination techniques to prevent collapse of the ribs separating adjacent channels while assuring adequate contact pressure to prevent de-bonding during co-sintering. The ITM Syngas process places severe demands on the membrane material. The membrane must simultaneously meet the criteria of being thermodynamically stable in the high-pressure, reducing, natural gas feed and intermediate synthesis gas; being thermodynamically stable in the low-pressure, oxidizing air feed; having sufficient mixed electronic and oxygen ion conductivity to achieve economically attractive oxygen fluxes; and having the requisite mechanical properties to meet lifetime and reliability criteria.

THE DUAL-ZONE BRAZED ALUMINUM PLATE REBOILER-CONDENSER

The boiling process and characteristics of conventional thermosyphon reboilers using plate-fin or enhanced boiling surface geometries are briefly reviewed. The limitations of these configurations can be overcome by the use of separate heat transfer surfaces in two sequential boiling zones. The heat transfer improvement obtained with the new configuration is described. Data are presented for a pilot scale test unit which demonstrate the capability for reduction of reboiler-condenser temperature difference by more than 1/3.