Asking for advice on the catalyst of acetylene hydrogenation reactor---Extra points represent my heart

Basic situation of an ethylene plant: For two-stage beds, the alkyne content at the inlet of the first stage is 1.75% mol, which is common, and the maximum is 2% mol. The alkyne content at the inlet of the second stage is 0.3~0.35% mol, and there are also cases of operation at 0.2% or 0.4~0.45% mol. The processing capacity is 38.5t/h. 1. Never add crude hydrogen, and the initial inlet temperature of the first stage bed is 28~30℃ (new catalyst)/45~47℃ (after 8 years of use) ； The second stage bed corresponds to 45°C (new)/65~70°C (old) 2. The amount of green oil produced is very small. It is discharged twice a year, not much. Due to pipeline blockage, it is discharged directly into a large bucket, with a maximum of 30L/bed each time. 3. At the end of the operation, the outlet temperature reaches a maximum of 120°C, so the selectivity drops below 20%, and the switch can be made. In the final stage, the goal is to control the outlet without leaking acetylene, and there is no need to pay too much attention to the inlet temperature/outlet temperature. The highest stage is about 70℃, and the second stage is 80℃. 4. The operation is relatively stable. Most of the unqualified situations are caused by the abnormality of the hydrogen distribution regulating valve, which causes the hydrogen distribution volume to decrease or fluctuate significantly.: Compared with the domestic BC-H-20B G-58C, the BC-H-20B still has its advantages. The activity is even higher than that of G-58C, the selectivity is close, the operation cycle is good (12 to 18 months), and the price is also advantageous. statement: Not advertising. This post was last edited by dushanzi2000 on 2009-4-21 16:14 ]

What is the flow rate at the reactor inlet on the second floor? What about the reactor regeneration cycle? I would be very grateful if you could introduce the information of BC-H-20B!

G58C acetylene hydrogenation catalyst is used in the front hydrogenation process. There is no problem with hydrogen distribution. The amount of green oil is related to the temperature of the reactor. In the early stage of operation, when the temperature is low, the amount of green oil is small. In the later stage, when the temperature is high, the amount of green oil will increase. In addition, overhydrogenation will also increase the amount of green oil. The key point of operation is to control the temperature rise of each bed layer. In the early stage, it is mainly concentrated on the first bed.

When the 4th floor said this, I was confused. Is G-58C a pre-hydrogenation catalyst or a post-hydrogenation catalyst? Check the information quickly. Application of new carbon dihydrogenation catalyst G-58C in ethylene units "Progress in Chemical Industry", 2000, (03). ==> Post-hydrogenation catalyst Comparison of the operation of carbon dihydrogenation catalyst G-58C and BG-H-20A "Ethylene Industry" 2003, 15 (3) ==> Post-hydrogenation catalyst section answers questions on the third floor: The load has already been mentioned on the second floor, 38.5t/h, the reactor operating pressure is 1720~1760kPaG. In my impression, the shortest regeneration cycle of G-58C is less than 3 months, and the longest is 12 months (because I have to spend the winter, I am worried, so I switch in advance). Regarding the information about BC-H-20B, I will open a separate post when I have time and send out several operation reports. This post was last edited by dushanzi2000 on 2009-4-21 17:32 ]

Looking forward to the post on the 5th floor about the operation of carbon dioxide hydrogenation catalysts G-58C and BG-H-20A. Thank you, brother of Dushanzi!

G-58C is a post-hydrogenation catalyst, and the pre-hydrogenation catalysts are G-83C and G-83D.