Reforming technology for syngas production

Methane forming reactions using either steam or CO2 have been known to industry for a long time. These endothermic reactions require the investment of a relatively large amount of energy. German researchers, in the 1970's, conceived and developed the idea to use this reaction and the reverse methanation reaction in a closed loop for the transportation and distribution of nuclear heat. The idea was also adopted for use with solar energy as a heat source. Utilizing solar energy as the heat source, the Weismann Institute of Science has fabricated, installed and operated a complete loop capable of the conversion and transportation of over 400 kW of heat. This system can be operated with a wide range of CO2/H2O/CH4 feed mixtures. Steam reforming is the common reforming reaction in the ''open loop'' mode for the purpose of synthesis gas production. This is accomplished with a large excess of steam on a nickel catalyst. However, it has only recently been recognized that there is also a substantial market for CO2 reforming. The CO2/CH4 mixture in various proportions exists in many places and has, so far, not been used efficiently. The sources for this mixture are biogas produced in anaerobic digestion processes and gas resources such as the NATUNA gas field in Indonesia, and many others. Therefore, the system of CO2/CH4 deserves more attention. Commercial catalysts used for steam reforming based on nickel are not suitable for this system. Therefore, other catalysts based on Rhodium and Ruthenium have been developed and some performance data is presented in this paper. Also presented is a conceptual schematic layout of a CO2 reforming plant and matching methanator. A computer code for a detailed design of the entire loop in a commercial size system has been prepared where optimized operational conditions as well as equipment parameters can be determined. (author). 3 figs, 3 tabs