Ethylene plant

If the SD2 of reactor C2 is routed through the large bypass, since acetylene in C2 is lighter than ethylene, it still flows through the normal process from pre-cutting and deethanization to the ethylene column to become part of the product, resulting in substandard products. If the feed to the ethylene column is shut off promptly and the substandard product is sent to the storage tank area from the system before the ethylene column, the ethylene system can operate in a closed loop, which can help reduce the time required to obtain satisfactory-quality products. This is because the ethylene heat pump system is large, and it is difficult to separate acetylene once it contaminates the system, leading to a longer dilution time. As for the impact on the C3 reactor and the propylene column mentioned by the questioner, if such an impact does occur, it indicates that there is a problem with the temperature at the bottom of the high-pressure column; this causes C2 to enter the bottom of the column and from there proceed to the low-pressure column, the C3 reactor, and the propylene feed pre-separation column. First, it is necessary to determine whether the catalyst used in the C2/C3 reactors exhibits selectivity toward both propyne and acetylene, as well as to understand the order of this selectivity, in order to analyze the effect of acetylene on the C3 reactor. Secondly, if the light components cannot be returned to the cracking gas interstage tank in a timely manner within the low-pressure column system and the propylene feed pre-separation column, it will ultimately lead to an excess of C2 at the top of the propylene column, resulting in substandard propylene product.

Our carbon dioxide hydrogenation reactor allows both acetylene and MAPD to react within it; approximately 50% of the MAPD undergoes hydrogenation in this reactor. In order to reduce the load on the carbon triplet hydrogenation reactor, the feed for that reactor is obtained by mixing the reflux from the low-pressure depropanization tower with the bottom stream from the degasification tower, with a feed ratio of approximately 3:1 between the degasification tower stream and the low-pressure depropanization tower stream

Sorry, I forgot to remove the feed from the bottom of the ethane stripper. That being said, if acetylene is brought to the deethanizer, it still flows from the top of the tower, as acetylene is lighter than ethylene. If we don’t go down the route of propylene hydrogenation, the selectivity of the catalyst still needs to be determined by the manufacturer. The conditions you mentioned for introducing acetylene into the C3 hydrogenation unit and the propylene distillation column are too stringent; under normal operating procedures, it should not be introduced there.

I’ll check in the evening to see if our C2 reactor reacts to MAPD; from what I remember, it doesn’t react. Speaking of this, I know what’s bothering you – it’s the concern that the C3 reactor might be overloaded, right? I got the starting point wrong.