Weekly Topic 2011.1.1 Issue 10: The Significance of Using Purchased Methanol for Operation

This post was last edited by ivu800 on 2011-1-1 08:23. In the case of large-scale systems, distillation startup holds little significance. Distillation usually uses steam that is a by-product; when the upstream system is not in operation, where does the steam for distillation come from? When starting up with purchased methanol, the production load is certainly low (due to transportation constraints), and steam consumption is not cost-effective.

Starting up with purchased methanol – it’s probably a trial run. I guess no one would buy crude alcohol to produce refined alcohol.

Purchasing methanol serves two purposes: the first is to conduct trials of the distillation system, adjusting various process parameters and operating methods in order to carry out a preliminary assessment of the process and the equipment； The second important step is to clean the system; this is different from acid cleaning of the system. On one hand, it removes any rust that hasn’t been cleaned away through acid cleaning or water treatment, while on the other hand it ensures that the quality of methanol remains satisfactory after trial operation with methanol – an issue related primarily to acidity. Many methanol plants encounter similar problems, where the color of the pure methanol is not up to standard after the system goes into operation. However, the trial operation using purchased methanol is not a necessary step before starting production; a decision can be made after taking into account factors such as the capacity of the crude methanol storage tank, the production load after startup, and the sales of crude methanol. Just like when using methanol as a fuel for driving, there is no need to purchase methanol externally; it can be used directly in the production process. However, during the initial phase of operation, there were issues with the selection of certain pumps, and these issues could not be detected during the trial runs using fake materials.

Testing purchased crude methanol indicates a lack of information regarding the distillation system. There is concern that after the large-scale system is activated, abnormal distillation may prevent the removal of crude methanol. I don’t think it’s necessary to start distillation in advance.

Everyone, where does the methanol used in your low-temperature methanol washing come from? With such a large amount of water to be removed from the original methanol washing system, can a single water separation tower be sufficient to meet the requirements? Since the methanol used in low-temperature methanol washing has to be purchased externally, why not send that methanol back to the methanol distillation unit for re-distillation? By using the methanol distillation process, high-quality methanol can be produced, which can then be sent to the low-temperature methanol washing unit. Just as mentioned on the fourth floor. No experienced person can be sure of getting distillation up and running perfectly on the first try, after all, many things are difficult to predict.

I think it is very necessary to purchase methanol externally, mainly to test various equipment and get the distillation system ready in advance, which is quite useful for getting the entire process up and running.

Do none of the factories really use purchased methanol to operate?

It is pointless to purchase methanol from outside, as high-purity methanol can be used directly in the production process. The quality of high-purity methanol is related to that of crude methanol; if the high-purity methanol is of poor quality, it only results in some waste of steam, and this has nothing to do with purchasing methanol from outside.

We all use purchased methanol for distillation; we don’t produce it ourselves. We purchase hundreds of tons at a time from external suppliers; buying more after that use may not be relevant to your topic, but I’m happy to support you in posting it – we might even be able to exchange ideas

Advantages: First, it enables the testing of the distillation system, allowing for the identification of any issues within the system and their correction. Second, it facilitates the cleaning of the system. Third, for newly built plants that lack technical support from existing plants, it serves as a means of training new operators. Fourth, it allows for the early production of methanol, which can be used to showcase achievements to leaders such as the governor; generally, leaders pay close attention to new projects. Disadvantages: It involves significant consumption of utility resources, as well as labor and materials, in the initial stages