Catalytic cracking startup

This information should be included in the catalyst-related documentation. The process starts differently in various plants; generally, it varies when removing the oil and gas blind flanges. The process can be divided into several main stages: 1) Introduction of main air and ensuring airtightness; 2) Ignition and heating – at this stage, steam from the vapor drum can be introduced; 3) Maintaining constant temperatures at 350 degrees and 550 degrees, followed by thermal compression – at this point, water can be added to the vapor drum. After adding water, the pressure is monitored, and if it’s appropriate, the valve connecting to the pipeline system is gradually opened, allowing steam to flow into the pipeline network. If steam is generated in the vapor drum, it can then enter the pipeline network. 4) Separation of the two vessels and replacement of the sedimentator; 5) In some places, catalysts are added, while in others, the oil and gas blind flanges are removed and combustion oil is sprayed to stabilize the temperature. After the oil slurry in the distillation tower circulates, the two vessels are fluidized. 6) The reaction temperature is slightly increased to prepare for oil injection. Basically, the general steps are the same; however, the specific procedures may vary from one factory to another. This is my opinion, and I hope we can learn from each other and encourage one another.

With such high temperatures, is there water hammer in the incoming water?

After testing the seals of the two devices, fill them with water and raise the temperature along with drying

Is this your facility’s first time starting up? Our approach is to pressurize each steam drum at the beginning of operation, including the external heat exchangers. After the pressure testing is complete, water will still remain inside the heat transfer tubes. During the drying process, we maintain a liquid level in the steam drums, and depending on the amount of steam generated, we decide whether to vent the excess water on-site or feed it into the steam network

You bring in water like this to extract heat externally. Will the heat transfer tube not burst after the device starts operating?

External heat extraction provides protection at 100 degrees with water.

No problem at all; the water that enters the air tank is deoxygenated water, and its temperature is over 100 degrees, so there’s no issue.

No, the water is hot; as long as you can see the liquid level, adding a large amount of water will suffice.

Our approach here is basically the same as yours – we introduce water at an early stage; all that’s needed is to make sure the liquid level is maintained! However, the steam connection valve is opened directly, the vent valve remains closed, and once the vapor generation pressure in the drum exceeds the system pressure, it automatically connects to the pipeline network!