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1. Development of Linda dimethyl ether technology: In recent years, with the development of China’s coal chemical industry, the production of methanol and dimethyl ether has been moving rapidly toward larger-scale operations. A question that arises is: what should be the approach for building large-scale facilities for methanol and dimethyl ether production? Is it better to use a one-step process or a two-step process for converting syngas into dimethyl ether? We believe that scaling up methanol and dimethyl ether production cannot rely on simply enlarging the equipment or increasing the number of units used; the two-step process is mature and easy to implement, while the one-step process is more energy-efficient and cost-effective, giving it an advantage in terms of development potential. Linda Company has been engaged in technical development for many years, achieving a series of significant advancements in technology and engineering. 1.1 Technology for producing dimethyl ether from methanol dehydration: In the early days, the liquid-phase method of methanol dehydration was used to produce dimethyl ether. In 1965, the American company Mobil proposed a gas-phase dehydration method using zeolite molecular sieves as catalysts; subsequently, the Japanese company Mitsui Toyo Chemical introduced the use of Al2O3 as a dehydration catalyst. In the synthesis of methanol and dimethyl ether, the key technologies are catalysts and reactors. At present, the main research institutions in China responsible for developing catalysts for the gas-phase dehydration of methanol to dimethyl ether include the Southwest Research Institute of Chemical Industry, Shanghai Petrochemical Research Institute, Dalian Institute of Chemical Physics, Shanxi Coal Chemistry Research Institute, Zhejiang University, Nankai University, Northeast Normal University, and others. Currently, there are two types of solid catalysts. One type is gamma-alumina, which has good heat resistance and can be used at temperatures ranging from 260 to 360°C; it also has a long service life. However, its disadvantages include high reaction temperatures, low activity, and a tendency to produce hydrocarbon by-products, which is detrimental to the catalyst’s stability. Another category consists of zeolite molecular sieves such as ZSM-5, which have high activity and can operate at low temperatures; however, they have poor heat resistance, tend to form carbon deposits, and require regeneration. To this end, the Dalian Institute of Chemical Physics proposed using a method of staged and mixed loading of these two catalysts in a fixed-bed reactor, taking advantage of the high activity of zeolite molecular sieves and the stability of alumina, in order to achieve a low initial reaction temperature and extend the service life of the catalysts. At present, gas-phase dehydration catalysis in our country can meet the requirements for the two-step production of dimethyl ether. In 1998, Linda Company developed \"a process for the synthetic modification of alcohols and ethers along with a corresponding synthesis reactor,\" and a **patent was granted in 2001.\" In November 2003, the **Chemical Production Capacity Promotion Center arranged for East China University of Science and Technology, Linda Company, and Tianke Co., Ltd. of the Southwest Chemical Research Institute to sign a contract for jointly developing a new process for dimethyl ether production. At that time, Linda also provided a technical solution using its isothermal cold-tube reactors for the methanol dehydration to dimethyl ether process for Hebei XinAo’s project with an annual production capacity of 400 kt of dimethyl ether. Linda Company has leveraged its expertise in reactor development to successfully create technologies for producing dimethyl ether via one-step or two-step processes for syngas. It holds a total of 12 related patents, of which 7 have been granted (see Table 1). http://www.nmtech.com.cn/jishuwang/upload1/0804211138505019.jpg LinDa’s two-step process for producing dimethyl ether employs a gas-phase dehydration method, and process optimization is carried out using simulation software; this approach enables full recovery of the heat generated during the DME reaction, thereby reducing the consumption of utilities such as steam. The process flow is shown in Figure 1: http://www.nmtech.com.cn/jishuwang/upload1/0804211140133020.jpg 1. Methanol storage tank 2. Methanol preheater 3. Evaporator 4. Gas-to-gas heat exchanger 5. Startup electric furnace 6. DME reactor 7. Crude DME condenser 8. DME reboiler 9. DME distillation column 10. DME condenser 11. DME reflux tank 12. Methanol recovery column 13. Methanol condenser 14. Methanol reflux tank 15. Methanol column reboiler Figure 1: Process flow diagram of LinDa’s dimethyl ether production process. Advantages of this technology: (1) Small temperature difference across the catalyst layer, fewer by-products, and low methanol consumption. The isothermal DME reactor utilizes continuous heat exchange, combining both reaction and heat transfer functions; gas flows inside the reactor tubes while catalysts are filled outside them, resulting in a high catalyst loading factor. The temperature difference in the catalyst layer is small, which prevents overheating in the adiabatic reactor due to sudden cooling; as a result, the methanol conversion rate is high, there are few by-products, and the methanol consumption per ton of product is low. (2) Isothermal reaction, high catalyst production intensity. At the same catalytic dosage, the production capacity is increased by 50% compared to the quenched adiabatic reactor; combined with the improved catalyst loading efficiency of this reactor, this offers favorable conditions for large-scale dimethyl ether plants. (3) The process is simple, and production operations are convenient. The process mainly includes methanol vaporization and DME distillation for methanol recovery; it is simple to operate and the production process is easy to control. If there is a methanol synthesis unit, the methanol and water coming from the bottom of the DME distillation column can also be sent to the methanol synthesis process for methanol recovery. (4) With a low temperature at the inlet of the tower and a high temperature at the outlet, the reaction heat generated in the production of fuel-grade DME can be used in place of steam for heating the DME reboiler, requiring a lower steam pressure level. The inlet temperature of the isothermal reactor is around 160°C, which is much lower than that of cold-shock and adiabatic reactors, while the outlet temperature of the reactor is above 300°C. The gas from the reactor outlet can first be used to produce high-quality steam as a by-product or directly to heat the bottom of the separation tower, before being used to preheat the gas entering the DME reactor. For methanol vaporization and recovery, heating with 0.7 MPa steam is sufficient; DME plants do not require steam at pressures higher than 1.0 MPa. (5) Heat recovery from the reaction is efficient, resulting in low steam consumption. The reaction heat is used not only to preheat the methanol feed gas entering the tower but also for heating the DME or methanol reboilers, enabling efficient utilization of heat and reducing the consumption of steam and cooling water. The structure of the isothermal methanol dehydration reactor developed by Linda Company is shown in the attached drawings (Figure 2 depicts a reactor designed by another company with an annual production capacity of 500 kt of dimethyl ether). The heat generated during methanol dehydration is removed from the reactor in a continuous manner. The reactor serves both as a reaction vessel and as a heat exchange unit; gas flows inside the reactor tubes, while catalysts are filled outside these tubes. Methanol gas enters the DME reactor from the top of the reactor at around 160°C. It is evenly distributed in the upper space through a distributor 2, and then guided to the upper ring tubes 6 via gas guide pipes 16 (three ring tubes are shown in the diagram). The upper ring tubes are connected to the U-tubes 9 within the catalyst layer 10; from there, the gas is distributed to various tubes. Inside these tubes, the gas first flows from top to bottom, being heated to around 270°C, and then flows from bottom to top in counterflow mode to exchange heat with the catalyst layer outside the tubes, reaching a temperature of 300°C before entering the catalyst layer for reaction. The peak temperature during the reaction is around 320°C, and after the reaction, the gas exits the catalyst layer at around 310°C. The gas after the reaction exits the reactor from its lower part, while the catalyst outside the tubes can be removed through the discharge hole 14. The internal cooling tube bundle in the reactor adopts a U-tube structure or an upper and lower ring tube structure; using U-tubes reduces the number of welding points, resulting in a more reliable design. http://www.nmtech.com.cn/jishuwang/upload1/0804211141134237.jpg The reaction heat is exchanged through counterflow between the gas inside the tube, thereby reducing the axial temperature difference in the catalyst layer. Linda Company has developed its own simulation software for optimizing the reactor, which enables the axial temperature difference of the catalyst to be kept within 30°C ； This thereby increases the production efficiency of the catalyst, reduces the amount of catalyst required, and minimizes the formation of side reactions. (In China, the temperature difference in cold-quench type dimethyl ether towers is around 120°C; the temperature at the catalyst layer is less than 160°C, while the operating temperature is around 380°C. In one Chinese factory, insulated towers with inter-stage heat exchange also result in quite high temperatures, as shown in Table 2.) http://www.nmtech.com.cn/jishuwang/upload1/0804211144227111.jpg 1.2 LinDa’s one-step process for producing dimethyl ether 1.2.1 Problems associated with the one-step production of dimethyl ether There are three reactions involved in the conversion of syngas into dimethyl ether: Methanol synthesis: CO + 2H2 = CH3OH; Methanol dehydration: 2CH3OH = (CH3)2O + H2O; Carbon monoxide conversion: CO + H2O = H2 + CO2. The one-step process involves using a catalyst for methanol synthesis to produce methanol from syngas, without first condensing and separating it from the syngas; instead, the methanol is directly dehydrated using the same catalyst to yield dimethyl ether. This can be achieved by using a catalyst that has both methanol synthesis and dehydration functions in a single reactor, or by first synthesizing methanol in a methanol synthesis tower and then dehydrating it in a methanol dehydration tower, with the dimethyl ether being separated from the syngas afterward. Both approaches constitute one-step processes. The two-step method involves synthesizing methanol from syngas, and then producing dimethyl ether either by condensing and separating liquid crude methanol from the syngas, or through liquid-phase dehydration of pure methanol or gas-phase dehydration of methanol vapor. The existing one-step processes mainly use bimodal catalysts for methanol synthesis and dehydration; some also employ shift catalysts, with reactors available in fixed-bed and slurry-bed types. In recent years, both domestically and internationally, the view has been expressed that the two-step process is more rational and economically advantageous than the one-step process, which has led to difficulties in making breakthroughs in the key technologies of the one-step process and a perception that it lacks economic advantages. The main reasons are as follows: (1) Lower raw material utilization efficiency in the one-step process. One-step process: 3CO + 3H2 = (CH3)2O + CO2 ………(1); raw material utilization efficiency is 51%, with molecular weights of 46 and 44 respectively. Two-step process: Synthesis step: 2CO + 4H2 = 2CH3OH ………(2); raw material utilization efficiency is 100%. Dehydration step: 2CH3OH = (CH3)2O + H2O ……………(3); raw material utilization efficiency is 72%, with molecular weights of 46 and 18 respectively. This may seem logical, but in reality there is no such difference between the two processes. The reason is that the one-step synthesis does not require a H2/CO ratio of 1 in the synthetic gas; a ratio of H2/CO = 2 can also be used. Thus, the overall reaction becomes 2CO + 4H2 = (CH3)2O + H2O ………(4), which is essentially the combined reaction of equations (2) and (3) in the two-step process. In fact, in the production of methanol and dimethyl ether from syngas, 1 mole of CO and 1 mole of H2 play equivalent roles. Both CO2 and H2O have a heat value of zero. In the production of methanol and dimethyl ether from coal-based syngas, there is an excess of carbon, and CO2 is either converted to CO2 for decarburization before methanol synthesis or left as is until dimethyl ether synthesis. (2) The one-step process uses a bifunctional composite catalyst, but the two types of catalysts do not match well; the active center of the methanol catalyst is prone to being deactivated by the water vapor generated from the dehydration of methanol. This is an issue that needs to be addressed, but it can be solved by carrying out the methanol synthesis and dehydration reactions in separate reactors. (3) The one-step synthesis of methanol, as well as the dehydration of methanol and CO conversion, are all exothermic reactions, resulting in a large overall heat effect. If heat cannot be removed effectively, the methanol catalyst will overheat and become deactivated, which represents another technical challenge that must be addressed. (4) Using a dual-functional catalyst slurry-bed single-tower process, Nippon Steel Corporation has successfully built a DM ether production facility with a capacity of 100 tons per day based on a one-step slurry-bed process. The reactor has a diameter of 2.3 m and a height of 22 m, with a static slurry level of 15 m; this configuration ensures uniform temperature in the internally cooled slurry bed. The downside is that more than twice as much inert oil as catalyst is required, and the reactor is quite large in size. In the three-phase bed, the reactant gas first diffuses from the gas phase to the liquid phase, and then from the liquid phase to the catalyst surface; as a result, the reaction rate is slow, while the catalyst deactivates relatively quickly. 1.2.2 Linda’s isothermal methanol synthesis-methanol dehydration and separation one-step process for dimethyl ether production: After a thorough analysis of the advantages and disadvantages of existing one-step methods for producing dimethyl ether from syngas using bifunctional catalysts in fixed-bed or slurry-bed configurations, Linda developed the isothermal methanol synthesis-methanol dehydration and separation one-step process. This method involves converting syngas into dimethyl ether, with the methanol synthesis catalyst and the methanol dehydration catalyst being arranged in two layers within a single reactor, or separately in two reactors placed one after the other; both reactions take place in heat-exchange type reactors. One of the advantages of this method is that it overcomes the problem mentioned earlier, namely the mismatch in performance between catalysts with dual functions when they are used in the same reactor. It provides the most suitable temperature conditions for each type of catalyst used in methanol synthesis and methanol dehydration: 220–280°C for copper-based catalysts used in methanol synthesis, 260–360°C for alumina-based catalysts used in methanol dehydration, and a lower temperature than that required for methanol for HZSM-5 molecular sieves. This approach avoids the situation where one aspect is prioritized at the expense of another. The second advantage is that it prevents the two active centers in the composite bifunctional catalyst from interfering with each other, thus avoiding a situation in which both catalysts are used simultaneously for methanol synthesis and methanol dehydration; the products of the dehydration reaction, namely large amounts of steam, can damage the activity of the methanol synthesis catalyst. The third advantage is that the water vapor produced by the dehydration of methanol does not promote the conversion reaction of CO in the syngas; the products of this reaction are dimethyl ether, water, and methanol, with low levels of CO2, which thus does not increase the difficulty of separation. The aforementioned one-step hierarchical process is difficult to implement under the existing methanol synthesis conditions. The current net value of methanol synthesis and the methanol concentration at the outlet of the synthesis tower is around 5%. With such a high concentration of methanol in the syngas, only about 2% dimethyl ether is produced as a result of the methanol dehydration reaction. Under these conditions of low dimethyl ether concentration, the cost of producing dimethyl ether and separating it from the syngas is high. Obviously, the key here is to increase the content of methanol and dimethyl ether in the reaction gas. This requires increasing the aforementioned methanol dimethyl ether concentration by a factor of 1 or even more than 2, which necessitates addressing the issue from both the catalyst and reactor perspectives. Calculations show that it is difficult to overcome this challenge using the existing catalysts along with other existing domestic and foreign fixed-bed methanol synthesis reactors. Linda Company has developed a patented one-step process for producing dimethyl ether from syngas, using a new type of homogeneous methanol synthesis and methanol dehydration techniques. This patent uses a high-efficiency water-cooled reactor to synthesize methanol and dimethyl ether at concentrations several times higher than those achieved by existing technologies. 2 Engineering Progress of Linda’s Methanol Dimethyl Ether Technology: Linda Company’s achievements in the field of methanol have been recognized by China’s chemical industry; to date, it holds 18 authorized domestic and international patents. In particular, in terms of large-scale low-pressure methanol production, its low-pressure methanol synthesis technology won the Second Prize for Technical Invention in 2004 – this being the highest award ever granted to an enterprise in China’s chemical equipment sector. Linda’s isothermal reactors have been used in hundreds of projects for methanol production; 27 units utilize Linda’s low-pressure methanol synthesis technology along with corresponding synthesis towers, giving a total capacity of 4110 kt. Currently, 12 units have been successfully put into operation, with a total capacity of over 1,000 kt. Among the operational projects, the large-scale methanol plant in Inner Mongolia operated by Tianye, which uses natural gas as raw material and has an annual production capacity of 200 kt, has passed the assessment and verification procedures, exceeding its designed capacity ； The 200kt methanol produced at Shaanxi Weihua using Texaco water-coal slurry for gas generation was evaluated by experts from the Shaanxi Provincial Department of Science and Technology ； Yunnan Dawa’s methanol production plant, which utilizes 200 kt of coke oven gas per year, was also successfully put into operation recently (see Table 3 for details). Twelve units are set to come online in the near future, with a total capacity of 2,450 kt. These include the methanol synthesis unit at Dalian Dahuahua, which has its LEF already installed and is ready for operation; the methanol synthesis units at Shanxi Lanhua and Hulunbuir Dongneng, each with an annual capacity of 200 kt, have been completed and are awaiting shipment (see Table 4 for details). http://www.nmtech.com.cn/jishuwang/upload1/0804211145178182.jpg http://www.nmtech.com.cn/jishuwang/upload1/0804211145556424.jpg LinDa Company adopts an objective attitude toward its patented methanol synthesis reactor technology and its actual performance – one that is based on openness, a realistic approach, and evidence from real data. Hundreds of people have visited the 12 low-pressure methanol synthesis units that are already in operation to examine them firsthand and analyze the data on their online operation, which is rare among other patent developers both domestically and internationally. Through on-site inspections, it has been clearly demonstrated that the JW isothermal large-scale low-pressure methanol tower reactor boasts advantages such as a small volume, a small temperature difference in the catalytic bed, a high CO conversion rate, high productivity, low consumption of feed gas, low catalyst usage, and a high packing efficiency. Here are just three examples to illustrate: (1) The methanol plant in Weihua, Shaanxi, with an annual production capacity of 200 kt, uses Linde JWφ3000 isothermal methanol reactors; it was the first large-scale methanol plant to use Texaco-derived gas as raw material. This unit uses pressurized gasification of water-coal slurry; the purified syngas is fed to the isobaric methanol synthesis unit without compression. It is equipped with a domestically produced methanol catalyst, NC307, in a volume of 46.5 m3. Four sets of 28 temperature measurement points have been installed within the catalyst layer, which is over 7 meters thick, to comprehensively monitor the temperature distribution across the bed. This project, which is part of Shaanxi Province’s major science and technology initiatives, was successfully put into operation in May 2006, and on July 14, 2007, it passed the evaluation for scientific and technological achievements by the Shaanxi Provincial Department of Science and Technology. On the day of the evaluation, at the production site it was observed that the volume of raw gas was 63,000 m3 per hour (under standard conditions), the volume of recycled gas was 267,000 m3 per hour (under standard conditions). The synthesis pressure was 4.76 MPa, the temperature inside the reactor was 108°C, while the temperature outside the reactor was 244°C. The average temperature difference across the catalyst layer was less than 10°C, and the axial temperature difference was less than 15°C℃ ； Under the condition of 9.04% CO at the inlet of the tower, 2.28% CO2 was present at the outlet, with a one-pass conversion rate of CO of 75%. The daily production of pure methanol reached 660 t on August 13; the average daily production over the 3 days from August 11 to 13 was 647.86 t. The methanol production rate, thanks to the catalyst used, is higher than that of shell-and-tube methanol reactors with a diameter of 4 m under identical process conditions. The power consumption for circulation is 1,300 kWh, with 48 kWh of electricity required per ton of methanol. When the feed gas reaches a volume of 68,000 standard cubic meters and a synthesis pressure of 5.5 MPa, the daily methanol production will exceed 700 tons. The expert group’s assessment states that \"the air-cooled, evenly temperature-controlled large-scale methanol synthesis tower developed in this project has been successfully applied to the isobaric synthesis process using water-coal slurry pressurized gasification as the feed gas.\" Under strong exothermic conditions, it possesses excellent properties such as uniform temperature both radially and axially in the fixed-bed methanol synthesis catalyst bed, small temperature differences, stable operation, easy control, high catalyst production efficiency, and a high CO conversion rate. ”“Structurally, through the optimized design of the upper and lower cold tubes, it is possible to reduce the axial and planar temperature differences as well as raise the temperature at the hot spots ； The chemical agents are filled between the tubes, with a filling coefficient of over 70%; the reactor has a small volume, and the shell and internal components can expand and contract freely, thereby avoiding thermal stress ； The Kangti structure features a rational design, being simple and reliable; the catalyst is easy to load and unload, and its manufacturing, installation, and maintenance are straightforward ； Replacing imported duplex stainless steel with low-alloy steel and domestically produced stainless steel **reduced investment costs. ”“Major technological innovations related to the methanol synthesis tower” ； Through the expert evaluation of the 200kt large-scale methanol synthesis tower at Shaanxi Weihua, it has been clearly demonstrated that pressure-based methanol synthesis using water-coal slurry has a significant advantage in reducing energy consumption. It has also been shown that Linda’s large-scale homogeneous-temperature methanol towers not only offer advantages related to their larger scale but are also suitable for various types of feed gases. These represent a low-pressure methanol reactor technology with independent intellectual property rights, advanced process design, and cost savings. (2) CNOOC Inner Mongolia Tianye Group’s project with an annual production capacity of 200 kt of methanol utilized Linde’s patented JW low-pressure isothermal methanol synthesis tower technology. It was successfully put into operation in December 2005 and passed the assessment in July 2006. With a raw gas volume of 78,000 m3 (at standard conditions), the raw gas contains 12% CO and 14% CO2, and the daily output of pure methanol is 673–678 tons, which has exceeded the designed capacity. Asanobu’s system uses natural gas as a raw material and operates under the same process conditions as current methanol plants abroad, making it comparable to them. The actual operating data are more advanced than the specifications of similar methanol synthesis units provided abroad. Using the actual plant performance data from this facility, Linda Company verified the mathematical simulation software developed by Bai Xing for designing the methanol tower. The verification results showed that the model parameters used in the reactor design were reasonable, and the simulation outcomes were very close to the actual plant data. According to the calculations, under the operating conditions of synthetic pressure, raw gas composition, and gas flow rate required by the original design, the daily output of pure methanol will reach 719 tons. (3) Harbin Gasification Plant installed Lindahl’s first low-pressure isothermal methanol synthesis tower in 2000 to upgrade its original imported ICI quench tower. After the modification, the temperature difference across the catalyst layer in the methanol tower was reduced from over 60°C to around 10°C. With the same tower diameter and unchanged catalyst, feed gas, and inlet gas flow rate, increasing the conversion rate results in a production increase of over 50%. The 80 kt/a methanol plant built by Harbin Gasification in 2001 utilized Linde’s second low-pressure methanol column, with a catalyst volume of only 23 m3; it produced 240 tons of pure methanol per day. These performance figures are better than those of advanced foreign companies using similar types of columns with gas cooling, where the catalyst volume is 43 m3 and the production capacity is 375 tons per day. In addition to successfully developing various types of gas-cooled, isothermal, low-pressure methanol synthesis towers such as those with U-shaped tubes and upper/lower ring tubes, and putting more than 10 such units into operation, Linda Company has also developed vertical water-cooled types, horizontal water-cooled types, water-cooled axial towers, water-cooled radial towers, gas-cooled–water-cooled (water-tube type) combined reactors, and gas-cooled–water-tube type series reactors. It holds numerous patents granted both domestically and internationally, and these technologies are being gradually put into industrial use. At present, Linda is working on the completion of the horizontal water-cooled methanol synthesis tower at Inner Mongolia Sutianhua, which has an annual production capacity of 200 kt of methanol, as well as the vertical water-cooled methanol tower with an annual production capacity of 150 kt. In particular, the horizontal water-cooled methanol tower features a design pressure of 11.5 MPa, an inner diameter of 3400 mm, and a wall thickness of 137 mm; its weight is nearly 200 tons. The selection of materials for such high-pressure, high-temperature, large-diameter, thick-walled synthesis tower shells, as well as the processing techniques and the optimized design of the water-cooled heat exchange elements, were all taken into consideration during its development. Hangzhou Linda Company developed a reactor for the one-step fixed-bed synthesis of DME from water gas many years ago; it also designed an industrial reactor for the production of DME using bifunctional catalysts at Zhejiang University, and the catalytic production efficiency for DME synthesis in this reactor was twice that required originally. In recent years, Linda Company has signed contracts with various enterprises and design firms in Shanxi, Shaanxi, Inner Mongolia, Sichuan, Henan, and other regions for reactors using the methanol dehydration to dimethyl ether technology, with an annual production capacity of 200 kt each. Currently, the 100-hydrogen dimethyl ether production reactor of Asia New Energy Holding (Xinyang) Company is in the equipment manufacturing phase, and it will be delivered around the end of the year. Linda Company has filed patents for the one-step process for producing dimethyl ether, and has so far completed the mathematical modeling and structural design of an efficient water-cooled methanol synthesis reactor, as well as a dehydrating reactor for methanol using gas-cooled or water-cooled syngas as the reaction medium. The development of high-efficiency water-cooled reactors not only enables a significant increase in production capacity per methanol synthesis tower within a single production line, but also makes it possible to use a one-step process for dimethyl ether production, thus establishing a new technology for large-scale dimethyl ether manufacturing. The economic advantages of producing dimethyl ether directly from syngas are very evident. Obviously, one-step investment is cheaper. The methanol distillation unit and the methanol storage tanks (for crude and refined methanol) can be omitted; only dimethyl ether distillation and a dimethyl ether storage area are required. Basically, with an investment equivalent to that of a methanol production facility of similar capacity, the methanol production unit and the unit for producing dimethyl ether through methanol dehydration can be combined into one facility, thereby eliminating the costs associated with transporting methanol, reducing the number of employees, and lowering production costs. The one-step method is more energy-efficient and reduces consumption, with steam production of around 3 tons. Just as the achievements made in the field of large-scale low-pressure methanol synthesis have been significant, it is believed that LinDa Company’s dimethyl ether synthesis technology will also play an important role in the development of large-scale dimethyl ether production in China.