Design scale and composition of the methanation unit
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This post was last edited by jensse on 2012-6-14 06:38. The methanation unit produces a substitute for natural gas by subjecting the purified gas from the low-temperature methanol washing unit to methanation, natural gas compression, and natural gas drying. The methanation unit consists of three processes: methanation, natural gas drying, and natural gas compression. The production methods and process characteristics: Methanization is carried out using the David Company process, or sometimes the Topsoe process; nickel-based catalysts are employed in this process. The methanization technology has the following advantages: (1) It enables the production of high-purity alternative natural gas, with a methane volume fraction of up to 96% and a high calorific value of 37,000 kJ/Nm3. (2) The nickel-based CRG catalysts have been proven effective in industrial applications, having been used in various projects such as the coal-to-natural gas plants in the American Great Plains. These catalysts are of the pre-reduced type, which eliminates the need for equipment, hydrogen, and related operations required for reducing the catalyst during the initial startup phase ； (3) CRG catalysts have a wide range of applications, exhibit high and stable activity, and possess high mechanical strength at high temperatures ； (4) It can produce medium-pressure superheated steam, with high energy efficiency. In accordance with the requirements regarding the water dew point of natural gas transported to external locations, triethylene glycol dehydration technology is used for natural gas drying; this process is mature, reliable in performance, and widely applied. It has the following advantages: (1) Suitable for the dehydration of natural gas with high flow rates and high requirements for dew point reduction ； (2) It has high water absorption properties under operating conditions and is easy to regenerate; (3) it results in a low pressure drop in the absorption tower ；
Could someone upstairs explain David’s skills in more detail?
Upstairs, could you explain why methanation in the Tang Dynasty project used the David process instead of the Rucho process, which is already well-established in the American Great Plains? After all, the David methanation synthesis technique is being used for the first time.
Note: The Great Plains uses David’s technology
Correction for floor 4. The Great Plains is Ruchi’s technique.
This post was last edited by lflsedin on 2012-6-13 at 17:58. Could the original poster please explain the Davy technology used by the Tang Dynasty? I want to learn!*
David and Topsoo each have their own strengths. In methaneation, the key factors are catalysts and temperature control; for these aspects, they have adopted cyclic approaches of their own, but the paths of these cycles differ, which means their processes are different as well. Personally, I think Topsoo’s catalysts are better, while David excels in terms of process design and engineering. Therefore, when choosing a methaneation technology, it depends on what aspect the client prioritizes.
If we go into more detail, it comes down to confidentiality issues. Hehe, the Great Plains uses the UHDE process; the catalysts are supplied by BASF and Davy (there are documents in China mentioning this, though I can’t recall where exactly). Davy’s catalysts have withstood 20 years of use and are now quite mature. It’s not clear why the UHDE technology isn’t used; it’s likely that UHDE’s technology is being employed, as it covers everything from gasification at the upstream stage to methane synthesis at the downstream stage. (The gasifiers and methanol washing technologies currently in use come from UHDE, although significant improvements have been made, especially in terms of the gasifiers.)
Upstairs, I think it should be easier to integrate the entire setup if all parts are made of Luchi.
(4) It can produce medium-pressure superheated steam (5.2 MPaG, 460°C) with high energy efficiency. Why is it medium-pressure steam? “ Can David’s not produce high-pressure superheated steam? The methanation in the Great Plains is a Lurgi medium-pressure methanation process. It’s different from today’s high-temperature methanization processes; David’s methanization catalyst isn’t even 20 years old yet. Steam pre-conversion is somewhat similar, but don’t mix up the concepts.
According to a friend from Great Tang, the current progress of Great Tang is stuck on David’s manufacturing process； There’s also the issue of the waste heat boiler, which David simply can’t solve.