Discussion on Freezing and Condensation of Heating Lines in Refinery Units
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This problem cannot be avoided in the northern refinery. Let’s discuss how to avoid freezing and condensation of heating wires. When was the most difficult thing you encountered and how difficult was it?
The liquid sulfur is completely condensed. Cut the liquid sulfur line and weld a new one.
There are many reasons, but there are a few main ones: 1. It is best not to install a water trap. 2. If multiple heating lines return steam together, the return steam line must be under pressure. 3. Close your head more during the day and turn it up at night when there are fewer people around.
I think we need to strengthen inspections. I think we need to add drain valves for heat tracing. We can also combine multiple heat tracing lines into one pipeline to recycle condensate water.
It would be a waste not to install a trap. If it is installed, it will sometimes become clogged and cause the mixing line to freeze. I suggest that the vent valve be a valve flange and add 1 or 2 orifice plates. The effect is good, but the main thing is to check it frequently.
If it is steam tracing, it is recommended to use an imported small water trap, which is very easy to use. At the same time, no matter how good the water trap is, it must be well maintained so that it can last a long time. It is impossible not to install a water trap in the current energy-saving environment. Or use forced circulation hot water for heating, which has good energy saving and use effects. There is another type of heat tracing that is currently used in oil refining equipment, that is, electric heat tracing, which has good effects and is relatively easy to maintain.
The most difficult frozen pipeline I have ever encountered was a light hydrocarbon pipeline whose main line and heating wire froze to death at the same time, with a total length of 3,000 meters. We used steam for 3 days and 3 nights to blow it through, which wasted a lot of manpower and material resources. Hi! ! ! ! ! ! ! tired! ! ! ! ! ! ! ! ! ! ! ! ! ! Precautions: 1. Change the long pipeline to steam tracing and add a trap at the drainage point. 2. If the pipeline is long, the semi-heated wire should be divided into multiple sections. 3. Pay more attention to daily inspections. 4. The pipeline with high height should be changed to steam tracing. 5. It is best not to use the same trap for the exhaust outlet of the steam tracing pipeline. They should be separated.
Water heating is mostly used, which requires less maintenance and saves energy. The heating system needs more inspections in winter
This topic is very good. Generally, large companies divide steam into three categories: high, medium and low pressure. The spent steam is used as heat tracing steam for recovery, that is, condensate water is recycled and reused. Of course, oil, impurities, and metals such as Daqing Refinery and Jinan Refinery need to be removed. But smaller refineries like ours have to consider energy conservation issues. I personally think: 1. Consider this issue when installing a new device, reduce the number of heating cables and use isolation fluid such as instruments. 2. It is best to discharge the heating cable centrally, and a better drain trap (such as Armstrong and Gestra from Germany) must be installed at the discharge point.
Heat tracing is very important for oil refining equipment, especially when shutting down in winter. If it is not handled properly, the consequences will be serious. Therefore, based on my personal understanding, I should do the following:: 1. Essentially change the form of heating. For non-lifeline heating locations, water tracing can be considered. First, it can maximize the use of low-temperature heat, and second, it can reduce steam tracing hot spots. After all, it is much easier to care for a hot water pump than to care for multiple steam lines. 2. Reduce the number of steam tracings as much as possible, calculate the maximum length of heat available based on local climate conditions, and make full use of pipelines. One steam line should be accompanied by multiple process pipelines to reduce condensation points. 3. The condensation discharge points should be concentrated as much as possible to facilitate inspection. 4. The heating cable must be purged before being put into use to prevent rust residue inside from clogging the drain trap. 5. Drain traps must be installed, otherwise energy waste will be too serious. 6. Improve personnel quality and strengthen assessment.