About subsodium preparation
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This post was last posted by sunjl1981 on 2013-1-6 23:44 The editor has seen the quiet processes of several companies. The subsodium used is basically prepared and reacted on site. However, everyone knows that the chlorine and acetylene used to prepare subsodium are very easy to react and cause explosion. Therefore, there is a certain risk in terms of safety. Can subsodium be prepared outside the area where acetylene occurs, and then transported to the area for use? Please express your opinion. # , , &
The method mentioned by the poster is completely feasible, but production costs must be considered. Preparing sub-sodium outside the boundary will increase the operating costs of the pump and operators for sub-sodium transportation, and because sub-sodium will decompose in the air and cannot be stored for a long time, its utilization rate is higher when it is prepared and used now.
From a safety perspective, the explosion caused by reaction with acetylene mainly depends on the concentration and pH value of sodium subsodium (containing free chlorine). It has nothing to do with where hyposodium is deployed.
There is no problem in preparing hyposodium outside the boundary area for acetylene purification.
As long as the liquid levels of the sub-sodium storage tank and the sub-sodium high-level tank are maintained without fluid interruption, there will be no safety issues you are worried about. Of course, you can also take precautions just in case. In addition to the liquid level display alarm, you can also add a U-shaped liquid seal at the outlet of the sub-sodium high-level tank to ensure that there will be no problems even if the instrument fails or is powered off. However, the height of this liquid seal is a bit too high. Of course, off-site preparation is also a good option, and using subsodium for waste gas treatment is also an option.
What you are talking about is the old process configuration of subsodium. The current configuration is basically that concentrated subsodium is transported from chlorine treatment to the acetylene workshop, and it is OK to mix it directly with water or waste subsodium!
I would like to ask why the liquid level of the sub-sodium storage tank and the sub-sodium high-level tank is maintained without liquid interruption, and the safety issues you are worried about will not occur? And how to add the U-shaped liquid seal?
Because as long as the storage tank is constantly liquid, there is no possibility for acetylene to escape from the pipeline into the chlorine system. As long as there is no contact, how can there be any safety issues? In addition, you can add a U-shaped liquid seal at the outlet of the high-level tank. Anyway, the location and height are sufficient.
What if chlorine and acetylene are leaked at the same time? Will chlorine gas explode if it comes into direct contact with acetylene?
It is completely feasible to prepare subsodium outside the boundary area where acetylene occurs and then transport it to the boundary area for use. This is how my company handles it.
The possibility of simultaneous leakage of chlorine and acetylene is very small. All you have to do is to prepare for a rainy day, solve the possibility of simultaneous leakage from a management perspective, increase inspections, regularly inspect all dynamic and static seals, and solve the leakage problem as soon as possible. If the inspection is in place, there will be no simultaneous leaks, and trace amounts of acetylene and chlorine will not explode even if they are mixed with air.
Using a remote pressure transmitter to introduce the liquid level of the sub-sodium high-level tank into the DCS system and monitoring the presence of liquid can avoid the above situation.