is the behaviour of the HT shift reactor. As the ROG/ natural gas ratio increases, the temperature delta of the HT shift becomes smaller and smaller. This change occurs because the H 2 present in the ROG dilutes the syngas from the main reformer, lowering the CO concentration at the inlet of the reactor. So since fewer reactants are entering the reactor, the amount of heat generated is smaller. Results and discussion The possible drawbacks mentioned above were solved by using a suitable amine formulation for the O 2 present, using a reclaimer to remove amine degradation products from the system, and using stainless steel in critical equipment. As a result, production could be increased by around 25 t/d of CO 2 , and obviously this quantity stops emitting into the atmosphere. With a second SMR, the consumption of natural gas was reduced by around 60,000 Nm 3 /d. In total, considering both SMRs, the amount of CO 2 that avoided being sent into the atmosphere is 150 t/d, and the total reduction in the consumption of natural gas is 66,500 Nm 3 /d.
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Figure 3 Fuel supplied to the furnace varies, depending on the ROG/ natural gas ratio
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Figure 4 Temperature profile of the pre-reforming process as a function of the ROG/natural gas ratio
negative, zero or positive, and the process, unlike other reforming processes, can be operated adiabatically. Figure 4 shows the temperature profile of the pre-reforming process as a function of the ROG/natural gas ratio. As can be observed, when only natural gas is processed, the reaction is endothermic since the reforming reaction occurs exclusively. When starting to introduce ROG, the profile becomes increasingly exothermic as both the water-gas shift reaction and methanisation predominate. Another variable that is interesting to mention
References
1 Z Rabiei, Hydrogen management in refineries, Petroleum & Coal 54 (4) 357-368, 2012. 2 S Ratan, S Farnand, J Li, Hydrogen perspectives for 21st century refineries, Hydrocarbon Processing , 71-75, Sept 2014.
Marcelo Tagliabue marcelo.tagliabue@airliquide.com
www.decarbonisationtechnology.com
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