ENERGY CONSERVATION IN THE SYNTHESIS GAS PLANT

Abstract

This thesis presents a theoretical investigation on energy conservation in the manufacture of synthesis gas. This has been carried out by incorporating two modifications in the conventional process. These are the use of secondary reformer outlet gases as heat source in the primary reformer to supply partial heat requirement and the use of gas turbine in place of steam turbine for driving the process air compressor. The exhaust gases of the gas turbine have been utilized as combustion air in the primary reformer furnace and in the steam superheater. The effect of these modifications on various operating parameters have been considered. It has been observed that for the same operating parameters like steam/carbon ratio, primary reformer exit temperature etc, the proposed modifications decreases the fuel consumption in the modified process by about 14 % as compared to the conventional process. The results were obtained using a computer program. Therefore,the proposed modification process seems to be promising for energy conservation in synthesis gas.. In this investigation, the effects of primary reformer exit temperature and steam/carbon has also been discussed. As a result of data analysis, it has been found that steam/carbon ratio plays an important role to affect all the operating parameters as well as the total fuel requirement. Although, exit temperature of the primary reformer affects the operating parameters, it does not effect total fuel consumption of the process. From the investigation, it was concluded that the total fuel requirement of the process is minimum at a steam/carbon ratio of 2.5 and primary reformer exit temperature at 830°C. Under these conditions, the total fuel requirement of the modified process was found to be 16 % less as compared to the conventional process.