C F Braun Description of Ammonia Synthesis essays

C F Braun Description of Ammonia Synthesis essays There are several processes to produce ammonia synthesis gas. The C F Braun (now may be referenced as Kellogg) process is one of the most current and acceptable processes due to the fact that the natural gas feed is less expensive than hydrogen generated from coke and water. This process has several stages of reaction and catalytic conversion that make it more presentable to industry, which are discussed in further detail. For the present time, the steam/air reforming concepts based on natural gas and other light hydrocarbons are considered to be the dominating group for ammonia synthesis. The first stage of the process is a preliminary purification section, where impurities, primarily sulfur compounds, are removed from the gas stream. The desulfurization vessel contains a catalyst that hydrogenates organic sulfur to H2S, R-SH + H2 > H2 S + RH which is then absorbed. The purpose of removing the sulfur is to increase the life span of the instruments down stream that may be sensitive to this particular compound. The gas, along with steam, is then fed into the primary reformer. This is the only place within the process where an endothermic reaction takes place. The main steam reforming reactions are: The reforming is furnaced by fuel, and escapes from the top as the flue gas. This flue gas is further used to heat the convection section of the compressor system. Due to lower temperatures within the primary reactor, low conversion is accomplished. Therefore, the gas stream is sent to a secondary reformer where at higher exothermic temperatures a higher conversion is accomplished. Process air is introduced to help provide the elevated temperatures necessary along with the stoichiometric amounts of N2 needed in the synthetic gas stream. The gas stream exiting the reforming section contains too much carbon monoxide (CO), and is ...