In petrochemical crude oil deslagging heat exchangers, severe coking of sludge oil occurs during operation, which affects the heat exchange efficiency
Thread Content
The figure below shows the crude oil deslagging heat exchanger in the atmospheric and vacuum distillation unit of a petrochemical refining plant, where the crude oil flows inside the tubes, while the residue oil is on the outside of the tube bundle. After operating for about 2 years, severe coking occurred on the residue oil side of this heat exchanger, affecting its heat exchange efficiency.
Coking problems are usually caused by high temperatures and poor stability of the oil products, and are particularly common in crude oil desulfurization heat exchangers. Here are some solutions: 1. **Optimize operating conditions**: Reduce the operating temperature to minimize the thermal decomposition of the oil at high temperatures. 2. **Regular cleaning**: Periodically perform physical or chemical cleaning of the heat exchanger to remove fouling from its inner walls. 3. **Use of additives**: Add anti-coking additives to improve the thermal stability of the oil. 4. **Improved materials and design**: Use materials that are more resistant to high temperatures and coking, and optimize the design of the heat exchanger by increasing flow rates and reducing dead zones. 5. **Monitoring System**: Install temperature and pressure monitoring devices to monitor and adjust operating parameters in real time, thereby preventing coking. Through these measures, coking problems can be effectively reduced or prevented, thereby improving heat exchange efficiency. .
In fact, this is the case with almost every residue oil heat exchanger. Indeed, there’s no effective way to prevent diesel from seeping in during shutdowns, and that’s quite problematic. Additionally, it’s necessary to remove the core while the equipment is still hot; otherwise, it’s very difficult to do so