Study of the influence of pressure, temperature, steam / natural gas ratio on reforming process for ammonia production

Abstract

The purpose of the thesis work is to study the influence of pressure temperature, steam/natural gas ratio on reforming process for ammonia production. The thesis work is divided in two steps. In lirst step, a solution for calculating equilibrium composition of the products of the steam reforming at particular pressure, temperature and steam/natural gas ratio has been found out from the graphical representation of InK vs. I/T involve in the process. A large number of data representing conversion analysis of steam reforming of methane at different pressure, temperature and steam/natural gas ratio have been calculated and graphical representation showing influence of pressure, temperature and steam/natural gas ratio has been plotted. From the calculated values and graphical representation it can be seen that conversion of natural gas increases with the increase of temperature and steamING ratio, and decreases with the increase of operating pressure. If operating pressure has to be increased, for maximum conversion of natural gas both temperature and steam/natural gas ratio or any of them should be increased to compensate the decrease of conversion of natural gas at high pressure. In second step, for testing the validity of the theoretical analysis of steam reforming of natural gas, process conditions of primary reformer and secondary reformer of seven fertilizer factories in Bangladesh have been used to calculate the theoretical outlet compositions of the reformers. The fertilizer factories whose data have been used arc Zia Fertilizer Company Ltd. (ZFCL), Jam una Fertilizer Company Ltd. (.TFCL), Polash Urea Fertilizer Factory (PUFF), Natural Gas Fertilizer Factory (NOFF), Urea Fertilizer Factory Ltd. (UFFL), Chittagong Urea Fertilizer Ltd. (CUFL), and Karnaphuli Fertilizer Company Ltd (KAFCO). A comparison has been performed showing the theoretical values and the actual outlet equilibrium compositions of reflmners of different processes. A small discrepancy of theoretical values and actual values have been observed and the causes for these discrepancy have also been described.