Calculation of gross calorific value
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UOP conversion between oxygen for regeneration coking and raw coke! Which expert can do it? In other words, the relationship between the carbon content of the catalyst to be used and the instrument air! It’s not the kind of universal curve for regenerative charring! Fresh catalysts produce less coking, and the instrument air used for regeneration is also in small quantities! The one from UOP isn’t very clear!
This post was last edited by che7420 on 2011-1-15 09:38. Calculating the amount of coke in uop has little significance in actual production, as the deviations are too large; after all, we rely on the results from laboratory analyses. Let’s talk about plain cooking: at a rate of 100%, the value for the two conversion constants is 0.1, with an air volume of 400 NM3. Calculate the amount of coke. 1+100%=2/400*0.1=0.05 The coke content is 5%.
To calculate the coke content using the air consumption, the following formula can be used: X (wt%) = 100 / Where: X = Coke content in the raw catalyst, % (by weight) CCR = Catalyst circulation rate, kg/hr (pounds/hour) CCR = Designed maximum catalyst circulation rate * Percentage of actual catalyst circulation rate Y = Oxygen concentration at the inlet to the coking zone, molar fraction AT = Total combustion air consumption, Nm3/hr (standard cubic feet/hour) Note: For white catalyst combustion conditions (where only air is injected from below), AT = AL – VL Where: AL = Air flow rate to the drying zone, Nm3/hr (standard cubic feet/hour) VL = Excess air vent volume, Nm3/hr (standard cubic feet/hour) For black catalyst combustion conditions (where only air is injected from above), AT = AU Where: AU = Air flow rate leaving the coking zone, Nm3/hr (standard cubic feet/hour) This formula can be presented in chart form for easier use. The catalyst coke content calculated by this method merely represents the coke content of the catalyst that is currently entering the regenerator for coking. There is no function to predict the catalyst carbon deposition rate in the reforming reaction. It can only be used by operators to observe the trend in the catalyst carbon content over a certain period of time, as well as to determine whether the carbon buildup on the catalyst exceeds the expected levels and whether it is necessary to reduce the severity of the reforming reaction. Regarding what was said above, I disagree that the catalyst carbon content calculated in this way is inaccurate. On the contrary, I believe that the catalyst carbon content calculated using this method is very accurate and can fully correspond to actual production levels. The sampling and analysis of catalysts involve randomness, which makes the determination of carbon content less reliable compared to the calculation of continuous oxygen consumption.