Problems in the dimethyl ether production process
Thread Content
During the dimethyl ether production process, the methanol temperature at the reactor inlet remained almost unchanged; only the temperature in the stripping section of the vaporization tower changed, which resulted in excessively high bed temperatures in both the first and second sections of the reactor. What is the relationship between these two factors?
First of all, it’s clear that your description isn’t very detailed; moreover, the production processes are not well understood, and there aren’t many companies in China that produce dimethyl ether. It seems to be Tianyi Technology’s technology. What you might be referring to is a decrease in the temperature of the stripping section of the vaporization tower. Of course it will have an impact; lower temperatures can cause liquid to enter the reactor, and this may also lead to the reactor overheating
Reply to 2# Kuju Kaiso: Does the liquid you’re referring to mean methanol or water? ? ?
Reply to 3# Yunying: Where does the water come from in the dimethyl ether process? ? Dizzy
Reply to 4# Kuju Kaiso: If crude methanol is chosen as the feed material, will there be water present in it? And if the vaporization tower is not operated properly, could this water end up in the reactor?
Reply to 5# Yunying: Will introducing water into the dimethyl ether reactor cause the bed temperature to rise?
Reply to 6# Kuju Kaisei: It will increase the temperature of the reactor bed, and may even lead to excessive temperature rise.
Even with pure methanol, water is generated during the operation of the vaporization tower; in fact, the vaporization tower serves as a separator for methanol and water. If the temperature in the vaporization tower becomes too high, water vapor will be carried into the reactor. Once this water vapor enters, the temperature in the reactor can rise rapidly to over 400 degrees, which is harmful to the catalyst. Therefore, it is essential to strictly control the temperatures at the bottom and top of the vaporization tower within the specified ranges during operation.
What was said upstairs is one aspect of the issue; from my experience, water can end up in the reactor. But when that happens, the effect is a decrease in the temperature of the bed material inside the reactor, rather than an overtemperature. Overheating likely occurs due to an excessively low temperature in the retention section of the vaporization tower, which results in too little steam entering the reactor and insufficient driving force; this leads to localized concentration of reactions within the reactor and thus overheating. This kind of situation often occurs while driving.
We often encounter the situation described by the original poster while driving; in my opinion, the main reason is an uneven control of the amount of methanol vaporized in the vaporization tower, which causes a large amount of methanol to enter the reactor in an instant and leads to a spike in the reactor’s temperature. The operation of the vaporization tower is crucial; during startup, the increase in temperature and pressure must be gradual
The operation of the vaporization tower must be stable; even the slightest change can lead to variations in the amount of methanol that vaporizes, which in turn affects the temperature of the catalyst in the reactor