Operational problems with acid water stripping equipment?
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The twin-tower acid water stripping unit (which uses hydrocracking, hydrorefining, delayed coking, flare tanks, and water injection in the flare gas screw compressor as raw materials) cannot increase its current processing capacity (when the processing capacity is high, the ammonia stripping tower is old and the alkaline nitrogen in the purified water exceeds 100ppm). It has been continuously declining from the previous 32t/h to only 23t/h now.； I suspected that there was oil in the acidic water. I stopped the tower a few days ago and steamed it for 4 hours. It had no effect, but worsened. Could you please help analyze the reason?
With operating conditions: The acid water feed is 23t/h, the bottom of the deamination tower is 140 degrees, the top of the tower is 130 degrees, and the top pressure is 0.3MPa ； When the tower is flushed, the temperature and pressure at the top of the tower rise. We suspect the tower is clogged, but does anyone have experience with this and what could be causing the clog. This post was last edited by lionangelwkp on 2007-12-31 08:16 ]
It should be that the tray is clogged. Since there is acidic water from the coking unit in the feed to the stripper, the coke powder in this part of the water is serious. Over time, the stripper tray will be clogged. Solution: Stop tower cleaning.
Thank you moderator in advance, but I have the following questions: 1. If it is coke powder, why did I stop the tower a few days ago and steam it for 4 hours, but it had no effect and actually got worse? 2. Could it be scale accumulation (such as salt)? 3. This device always has problems in winter. Why? Our factory is in the north. 4. Is the problem that occurred after the acid water stripping device started up a medium-pressure diesel hydrotreating device related to the startup of the medium-pressure diesel hydrotreating device?
I am also very interested in the question raised by the poster. Our factory also has two sets of acidic water devices. As environmental awareness becomes stronger and stronger, the requirements for acidic water treatment are also getting higher and higher, and our devices often have problems. Let me give you some perspective on your question. Sulfur and ammonia in wastewater mainly exist in the form of NH4HS and (NH4)2S. Ammonia also forms (NH4)2CO3 and NH4HCO3 with CO2. These substances can be decomposed into ammonia, hydrogen sulfide and carbon dioxide under heating and vapor and separated from the water. Tray clogging occurs due to the formation of ammonium salts under certain conditions. The next step is to strengthen the deoiling of raw material tanks.
It is possible for ammonia and hydrogen sulfide to form salts together, but there will be salt in the deamination tower of the double-tower stripping. There is so much water in it that it will be easily dissolved.
Consider whether there are problems with other systems
The top pipeline of the deamination tower is prone to salt formation and generally has a water injection line that can be flushed online. This post was last edited by chengkang on 2009-4-18 22:23 ]
Isn’t there water at the top of the deamination tower? Can’t it dissolve the generated ammonia salt? Is it due to solubility that the ammonia salt is saturated and unable to dissolve?
Nowadays, environmental protection is getting more and more attention. Every refinery has one, and many refineries even have two sets of acid water desulfurization devices. Why is this issue no one paying attention to? Don’t we all encounter it a lot?
Have you measured the pressure difference of the tower? According to you, the downcomer pipe of the feed plate is blocked.
1. Consider the impact of emulsified oil in water, which has a great impact on the tower. 2. Consider the impact of coke powder. 3. Consider the tray problem. There is a problem with the tray, and the gas-liquid contact heat exchange effect is not good. 4. Consider the reboiler problem, whether there is leakage.
The coke powder carryover was serious, and a similar test situation occurred in the stripping tower of a certain factory to strengthen deoiling.
study* Okay, our installation is a single-column stripping, and we have never been exposed to double-column stripping. Thank you for the question!
1. Wash once with water 2. Check the side line extraction 3. Restart the feeding process
It should be salt formation on the tray. Measure the pressure difference from the top of the tower to the bottom of the tower. You should be able to determine where the problem lies.
As your processing capacity increases, you slightly increase the tower top pressure and tower bottom temperature, and at the same time increase the tower bottom liquid level. This will not only increase the downward pressure drop, but also the residence time of the acidic water in the tower, which is beneficial to the operation.
Haha, our unit just had a similar situation, that is, the tower was blocked by burnt powder.
Come in and take a look at the situation. I want to know more about acid stripping towers. That guy has some information on this. Can you please pass it on? Thank you very much.
If the tower is blocked by burnt powder, is there any good solution?
Sometimes changes in water quality will cause the purified water to fail. In our case, it is usually adjusted by injecting alkali. If you have any questions about the acid water gas stripping process, you can go to the sulfur recovery section in the coal chemical industry section to learn more. * Discussion, the acid water problem is mostly there. Please also ask the refining moderator to move the topic of acid water process to the sulfur recovery section when sorting it out, thank you.