【MTBE】What are the problems with MTBE purging?
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This post was last edited by Xiao Gong 1985 on 2016-3-7 at 10:51. After several days of MTBE purging, I would like to discuss with everyone the various issues that arose during this process. . . 1. During the nitrogen purging process in the reactor (expansion bed, with material entering from below and exiting from above), the bed temperature drops to below zero, sometimes even by more than ten degrees below zero. What is the reason, and how can it be avoided? 2. With a catalyst container, after nitrogen purging reduces the content of flammable gases to 5%, methanol and other ethers can account for up to 50% of the mixture after washing – what is the reason for this, and how should such a washed mixture be handled? 3. How do experienced managers handle MTBE containers with catalysts? @Guan Gongyu
@Fengshan @xutaotao xu I haven’t seen him. We use a fixed-bed system
In this set of equipment, except for the distillation tower which is packaged, the rest consists of ceramic balls plus loose catalyst
1. Are you sure the temperature display is normal? Is it the endothermic gasification of tetrahydrocarbons attached to the catalyst that causes the temperature to drop? It seems that one can only empty it as much as possible. But it cannot be replaced in the catalyst. If a catalyst is not needed, consider cleaning it directly with deionized water.
Yes, it’s possible that the alcohol cleaning effect wasn’t good at that time, with too much C4 component. . On top of that, the purging effect of N2 gas is not as significant as that of steam
Do you plan to keep using your catalyst, or dispose of it? If used, steam cannot be used either. Did you wash it with methanol before nitrogen displacement? Isn’t it replaced after it’s emptied? It is likely that tetrahydrocarbon attaches to methanol. I haven’t seen the actual emptying and replacement process, so I can only analyze these aspects for you.
I think it would be better to keep the reactor pressure above 0.4 MPaG during reactor purging
I think it would be better to keep the reactor pressure above 0.4 MPaG during reactor purging
You mean to keep butane in the liquid phase? But the nitrogen pressure is around 6 kilograms, I guess. Replacement pressure relief isn’t very convenient either, is it?
During the material withdrawal process, maintain a pressure of around 0.4 MPaG. Once the material withdrawal is complete, if the reactor catalyst needs to be replaced, it can be purged and replaced using steam; if the catalyst does not need to be replaced, nitrogen is used for purging. The reactor is pressurized to around 0.55 MPaG, then the pressure is reduced to around 0.35 MPaG by releasing it to the flare, and this process is repeated. But this replacement process is very slow.
During the material withdrawal process, maintain a pressure of around 0.4 MPaG. Once the material withdrawal is complete, if the reactor catalyst needs to be replaced, it can be purged and replaced using steam; if the catalyst does not need to be replaced, nitrogen is used for purging. The reactor is pressurized to around 0.55 MPaG, then the pressure is reduced to around 0.35 MPaG by releasing it to the flare, and this process is repeated. But this replacement process is very slow.