Finally, the latest weekly topic: Large-scale Methanol
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2015 is coming to an end, and 2016 is upon us. Here, I wish everyone fruitful results and success in their endeavors in the new year! The family’s wish has come true! This is the final and most up-to-date weekly topic for the methanol section; we hope everyone will participate actively, as the rewards will be very generous! There are still true friends close at home; though rivers flow far, my heart remains not far away. I’m even more glad to receive wishes for a clean New Year. I hope winter will pass and spring will fill the garden. Methanol: Weekly topic – Whose technology is used in large-scale methanol production? What are the advantages and disadvantages? December 28, 2015 – January 4, 2016: As technologies such as coal-to-olefins have improved, the scale of coal-to-methanol production in the emerging coal chemical industry has also increased. A capacity of 600,000 tons is considered to be a medium-scale facility. Companies like Davy, Lurgi, Topsoe, and Cassali have already demonstrated their superiority in terms of methanol production on a million-ton scale; Davy and Lurgi are at par with each other, while companies such as Cassali and Topsoe, along with Linde, Guochang, Anchun, and Jutuo, can only compete at the 600,000-ton level. There is hope for domestically developed million-ton methanol production processes – something that has been awaited for over 10 years. Let’s hope that 2016 will bring some surprises!
The Topsoo adiabatic shell-and-tube tower uses Casari internals in the form of heat exchange plates; Topsoo’s advantage lies in its catalysts, while the Casari synthesis tower has its own advantages. In my opinion, a combination of the Casari synthesis tower with a Lurgi air cooling tower would be even more effective
Original poster, I really haven’t used this before, so I don’t know
Domestic technologies, LinDa and Huali Technology, can both reach 600,000 tons. For the next stage of development, I personally believe that adding rare earth elements as catalysts – by making them smaller in size – can increase their activity and surface area, thereby improving the one-way conversion rate. Rather than trying to make the reactors and heat exchangers larger, my goal is to achieve a synthesis pressure of 5 megapascals with an air velocity of over 12,000. If the average yield can be increased to 1.5–1.75 tons per cubic meter of catalyst per hour, then a synthesis tower with a capacity of 600,000 tons would require 45–50 cubic meters of catalyst, which significantly reduces the technical barriers involved in its production.
The key to reducing the investment and cost per ton of methanol in large methanol plants lies in increasing the capacity of each series and each tower, rather than simply combining multiple towers and series. Currently, the major foreign methanol production technologies are Lurgi and DAVY technologies. Lurgi’s 1.57 million tons per year large-scale methanol process consists of 3 methanol towers; one of these, which is air-cooled, serves both as a reactor and as a heat exchanger, with a capacity of 556,000 tons per year per tower. With this water-cooled and air-cooled combined technology, the unit is an axial tower; the total pressure difference between the inlets and outlets of the two synthetic towers connected in series is as high as 0.7 MPa, and the amount of steam generated per ton of alcohol produced is less than 1 ton. According to Lurgi’s latest information, this major methanol technology is still under development and improvement. The original technical plan for DAVY’s large methanol plant involved two radial towers with a diameter of 5 meters, each with a capacity of 1.8 million tons per year, along with one circulation unit connected in series and parallel; during operation, the temperature exceeded 300°C. It is now modified to consist of two identical series of towers, each with a capacity of 900,000 tons per year; each set includes a pre-methanol synthesis tower and a large radial tower, as well as circulation equipment, heat exchange units, and separation equipment. However, the maximum synthesis temperature is set at 315°C. Although these two foreign large-scale methanol production technologies can utilize the heat-resistant and highly active methanol catalysts produced by Clariant and Dow Chemical, their large-scale methanol production processes and the design of their methanol reactors are not optimized to work in conjunction with these high-quality catalysts, which limits the further realization of their overall advantages.
A catalyst is truly good only when it is well-made! So you get it: lol
In a tower, gas flow and heat exchange are the key factors; due to the short flow path in David’s design, the methanol concentration at the outlet can only reach around 5%, which results in a large volume of circulating gas as well as a high density for it. The flow channel of the Luchi 2+1 gas contact catalyst is about eighteen meters long; the vast majority of the carbon is converted during a single pass. Due to high resistance, the pressure difference is large, and because the flow channel is long, there are naturally more impurity components in the reaction mixture. The alcohol content at the outlet is around 16%, the recycle ratio is low, the gas density is low, and the bleed loss is also small, making the operation very economical.
There is no shortage of GUO production technologies at the moment; what’s lacking is support in the form of policies and incentives. No one is willing to take risks. Things would be different if there were favorable conditions
Mainly, everyone wants to use what’s already available. They aren’t very interested in local production. In the best case, following the DMTO model, a joint venture between the technical unit and the construction unit should be established to boost enthusiasm for cooperation between the two parties.
It’s a big problem: engineering companies look down on research institutions, while research institutions have difficulty finding engineering companies. Research institutions are even less willing to give their achievements to companies for free, and of course companies are also reluctant to take on the risks associated with testing. As a precaution, follow the modular approach suggested by the design institute to ensure seamless integration of the processes. This is the current situation in the domestic market: as a result, new technologies fail to see the light of day and cannot be widely adopted, while businesses face high investment costs for construction and elevated operating expenses. Companies have similar manufacturing processes; they compete by lowering product prices, resulting in no profits for any of them. There is a severe surplus of products, and there is no way to find solutions for reforming these situations. Engineering companies focus on construction work, with rigid approaches to manufacturing processes. Under the current circumstances, they still have to take on projects just to make ends meet, otherwise they risk losing business and having to dissolve their teams. The tasks of research are primarily carried out between research institutes and universities; these institutions lack the necessary capabilities in process engineering, and although they produce many results, there are very few cases where process validation is achieved, that is, few pilot projects are conducted. If (ˇˍˇ) wants to～-----connect process research with enterprises, and conduct trials and experiments within those enterprises once results are achieved; in this way, the results can be quickly refined and perfected before being brought to market. But this practice is very rare in the domestic industry.
Ruchita, I’ve always heard that it couldn’t be transported to the interior areas. Has that problem been resolved now? With a diameter of 6.1 meters and mounted on a large transport vehicle, starting from the port and taking the highway – can it pass through the toll gates?