Dear ethylene friends, is there any LPG cracking?
Thread Content
Dear ethylene industry peers, do you have any information on LPG cracking? Please share it if you have. Also, what should be the COT value for LPG cracking, and what should be the vapor-to-hydrocarbon ratio? Thank you.
The conditions for ethylene cracking are generally specified in detail in the operating procedures, but this information constitutes trade secrets of the manufacturers or patent holders, so it may not be appropriate to disseminate it online. In ethylene cracking units, one or two cracking furnaces are typically installed for the cracking of light hydrocarbons.
We also have light hydrocarbon cracking, but it’s only the cracking of LPG that has increased. I was wondering what level is generally used to control COT; this shouldn’t be considered confidential, right?
It depends on the type of furnace and the specific composition of the raw materials; generally, it’s around 850
The lighter the raw material, the higher the COT and the lower the gasoline ratio. A certain company’s LPG cracking temperature is 855, with a dilution ratio of 0.3–0.4
Thank you, we have finally decided on 853, with a hydrocarbon to gas ratio of 0.5.
A vapor-to-hydrocarbon ratio of 0.5 is a bit high; generally, it’s 0.3–0.4
At the end of operation, the DS ratio can be appropriately increased in the furnace
Why? Please explain it
Our system works as follows: the diluted steam helps to reduce the partial pressure of hydrocarbons and also serves to remove coke buildup. Towards the end of the furnace’s operation, when coke accumulation becomes severe, the ratio of this diluted steam is increased. With the same cracking outlet temperature, the temperature of the furnace tubes is lower at the beginning but rises to around 1100 degrees towards the end; this also helps to prevent the furnace tubes from being damaged.