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The main process steps in the industrial chain for producing methanol and downstream products through coal gasification include: gasifying coal to produce syngas; synthesizing methanol or dimethyl ether; dehydrating methanol to produce dimethyl ether; and catalytically synthesizing hydrocarbon products from methanol or dimethyl ether (mainly propylene). Gasification technology is classified according to the type of gasifier, mainly including fixed-bed, fluidized-bed, and gas-flow bed types. Considering aspects such as technical advancement, energy consumption, and environmental protection, fluidized bed gasification is the preferred choice for large-scale methanol gasification. Representative fluidized bed gasification methods include: Texaco water coal slurry, Shell dry powder, and the multi-nozzle water coal slurry developed by East China University of Science and Technology. The coal water slurry gasification technology developed by Texaco was adopted early on; it is a mature technology, and there are numerous industrial plants using it both domestically and internationally. However, its gasification efficiency is low, and its oxygen consumption is high. Shell’s dry powder fluidized bed gasification technology has been widely used in China over the past two years due to its high thermal efficiency and wide suitability for different types of coal; it has been adopted in more than 10 coal chemical projects, although the investment required is relatively high. The multi-nozzle water-coal slurry gasification technology developed by East China University of Science and Technology has also been put into industrial use; it improves the carbon utilization rate compared to single-nozzle water-coal slurry gasification. However, the multi-nozzle multi-channel control system increases the equipment investment and maintenance workload. Methanol is synthesized from syngas under catalytic conditions, and its production on a commercial scale has already been achieved. The currently used methanol synthesis methods are mainly fixed-bed types, while slurry-bed methods are still in the development stage. The most commonly used type of synthesis tower is the tubular synthesis tower, but it requires significant investment. Large-scale plants are better suited to use shell-and-tube synthesis towers, multi-bed internal heat exchange synthesis towers, and tubular synthesis towers with fixed tube sheets. Methanol is an important chemical raw material, widely used as a basic organic chemical in fields such as fine chemicals, plastics, pharmaceuticals, and forest product processing. It can also be used as a substitute fuel for engines, and the consumption of methanol fuel has become one of the main drivers of demand for this substance. Dimethyl ether can be produced through a two-step process of liquid or gas-phase dehydration of methanol, or it can be synthesized in one step from syngas. Compared with the two-step method, the one-step method offers advantages such as higher efficiency, fewer processing steps, and lower production costs; the large-scale production of dimethyl ether primarily employs the one-step method. Dimethyl ether has many unique applications in the chemical industry, such as in pharmaceuticals and pesticides. More importantly, it can be used as a substitute fuel for diesel in vehicles, as well as a substitute for LPG as a fuel for household use. The MTO technology, which uses methanol as a raw material to produce low-carbon olefins, has become the essential pathway for developing new coal-based chemical industries and realizing the strategy of \"replacing oil with coal\". The products derived from this technology, such as ethylene and propylene, as well as downstream products like ethylene glycol, acrylic acid, polyethylene, and polypropylene, enjoy broad market prospects and hold great economic potential. UOP/Hydro’s MTO technology is ready for industrial application, and the Dalian Institute of Chemical Physics under the Chinese Academy of Sciences is also working on the development of this technology. Lucky Company’s MTP technology for producing propylene from methanol has also completed the process design for its industrial-scale facility, and has entered the phase of actual industrial implementation