Salt formation in high pressure heat exchanger
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Our device is a gasoline and diesel hydrogenation device. Recently, the heat exchange effect of our No. 2 high-pressure heat exchanger is not good. A similar situation occurred before the maintenance. We suspect that it is caused by salt formation. I wonder if you have experienced such a situation? How to deal with it? Thanks!
Generally, it can be treated with water injection. But to do a good job in control and prevention, we use reformed H2, which has a high chloride ion content and has a dechlorination tank. The effect is good and can be used as a reference.
Check the salt content of the raw materials to see what they are like. What is the situation of your raw materials? What kind of equipment are they made of?
You can add water line before your No. 2 heat exchanger tube to play a certain role.
If it is confirmed that it is salt formation, adding water will definitely solve the problem!
Our equipment processes coked gasoline and diesel, and unqualified normal and vacuum diesel. We have a water injection point behind the No. 2 heat exchanger, but not in front.
The inlet temperature of our No. 2 heat exchanger is about 250 degrees. Under normal circumstances, there should be no salt formation. The heat exchange effect of No. 3 is quite good. If there is salt formation, the problem should occur first. And our No. 2 cannot be filled with water during normal production. Brothers, how can we solve it now? Thanks!
The chlorine content of the raw material is too high, and the crystallization point of ammonium chloride is high. If there is no water injection facility, then when the water washing device is shut down for maintenance, add a water injection facility at the pipe entrance of the 2# heat exchanger.
We have two channels of water injection in front of high-pressure air cooling and in front of reaction product heat exchanger
Explain your reaction effluent heat exchange process and the temperatures before and after heat exchange at each level!
The crystallization temperature of ammonium chloride salt is between 220 and 230 degrees. If the inlet temperature of your heat exchanger is around 250 degrees, some ammonium chloride salt will crystallize. Therefore, it is recommended to change the water injection point to the front of the heat exchanger, or increase the inlet temperature of heat exchanger No. 2 and move the ammonium chloride salt crystallization point to the rear end.