I have a question regarding catalytic cracking
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:@I recently got a math problem; I don’t understand the questions in it, so I’m asking the experts for help! Title: A certain catalytic cracking unit has a fresh feed processing capacity of 131 t/hr, a recycle oil volume of 150 t/hr, and a catalyst circulation volume between the two reactors of 1700 t/hr. The product distribution of this unit is as follows (all values are in mass percentage): feed oil 100, dry gas 4.27, liquefied gas 15.00, gasoline 41.53, diesel 31.61, coke 6.65, and losses 0.93. Is the amount of re-refined oil here the total mass of the product distribution? If I want to calculate the one-way conversion rate, how should I do it?
How can the amount of reprocessed oil be greater than the amount of fresh feed? Such a thing is impossible! It must be a mistake!
No! This is still an exam question from East China Petroleum this year; someone asked me to work on it. I’m stunned! I didn’t quite understand it either, but what I gave them was the original question.
The one-way conversion rate refers to the conversion rate of the total feedstock (including fresh feed, reprocessed oil, and reprocessed oil slurry) upon a single pass through the reactor. One-way conversion rate = (dry gas + liquefied gas + gasoline + coke) / total feed * 100% = (4.27 + 15 + 41.53 + 6.65) / (131 + 150) * 100% = 24%. 1. The amount of oil reprocessed in this calculation is too large. 2. The catalyst circulation rate is provided to help you calculate the catalyst-to-oil ratio: Catalyst-to-oil ratio = Catalyst circulation rate / Total feed volume = 1700 / (131 + 150) = 6.08 file:///C:%5CDOCUME%7E1%5CADMINI%7E1%5CLOCALS%7E1%5CTemp%5Cmsohtmlclip1%5C01%5Cclip_image002.pngfile:///C:%5CDOCUME%7E1%5CADMINI%7E1%5CLOCALS%7E1%5CTemp%5Cmsohtmlclip1%5C01%5Cclip_image002.png
I’m sorry! The product distribution of the device is given as a mass percentage, and I have no idea what the actual mass of each product is! This exam question is really frustrating!
The formula given here uses mass percentage as the basis for calculation. As for the calculation of the yield (conversion rate) for each product, you can refer to the “FAQ on Catalytic Cracking Technology”. There are download links on the forum!