Correct understanding and objective analysis of dimethyl ether fuel

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Dimethyl ether is an important green industrial product. Its main previous uses were: Aerosols, refrigerants, foaming agents, organic synthetic raw materials, etc. In recent years, due to the similar combustion characteristics of dimethyl ether to LPG, it has been favored to replace LPG (liquefied petroleum gas) as a civilian fuel and can also be used as a diesel additive. Therefore, dimethyl ether has become one of the main varieties of alcohol ether fuel. As a fuel substitute, dimethyl ether is said to have the following characteristics: It has good flammability, is easy to compress, and is safer. It can be blended into city gas or natural gas for peak shaving purposes. It can also improve gas quality and increase calorific value. The cost of large-scale production is lower than diesel, propane and compressed natural gas. This product was once very popular, and now there are about 60 units under construction at the same time. 　However, the current publicity of dimethyl ether is a bit excessive, and dimethyl ether fuel also has many shortcomings, which are mainly reflected in the following points:: 　　There are high requirements for engine design, and vehicles using dimethyl ether must undergo engine modifications. The rubber sealing ring of the cylinder valve used to hold liquefied gas is easily corroded by dimethyl ether, causing leakage. The latent heat of vaporization of dimethyl ether is relatively high. If pure dimethyl ether is used as household bottled fuel, the combustion will be unstable and the use time will be shortened. 　　In order to promote the benefits of dimethyl ether fuel, some scientific researchers and economists claim that CO2 can be used to produce dimethyl ether. They did not understand that the research topic of CO2 hydrogenation to produce dimethyl ether was to solve the catalytic process and product gas composition problems in the one-step production of dimethyl ether, and mistakenly believed that this topic could become a standard production method of dimethyl ether. Therefore, they proposed to use the results of this topic for the production of dimethyl ether. Such publicity interfered with the formulation of dimethyl ether production policies. 　　Industrial development suffered setbacks and once pinned its hopes on dimethyl ether as an alternative fuel. * * Due to the ban imposed by the General Administration of Quality Supervision, Inspection and Quarantine, it cannot be added to liquefied gas, which will have a certain impact on the development of dimethyl ether. 　　The meaning of this document is that the use of dimethyl ether and mixed fuel of dimethyl ether and LPG should be dedicated to gas, bottle, and use. The document does not prohibit the mixing of dimethyl ether into LPG, but does not prohibit the mixing of dimethyl ether into cylinders containing LPG. 　　Dimethyl ether is currently under serious attack as an alternative fuel. In 2008, my country's total large-scale production capacity of dimethyl ether exceeded 4.8 million tons/year. In 2007 alone, a dimethyl ether project with a production capacity of over one million tons was put into operation. Nowadays, most devices are difficult to operate normally, and the average operating rate is generally less than 50%. The dimethyl ether industry has shown a situation of large production capacity and low output. 　　In fact, solving the problem of dimethyl ether is very simple, just like the problem of methanol gasoline. Dimethyl ether is the intermediate product of methanol to gasoline, so as long as the coal-to-methanol and methanol-to-gasoline (MTG) processes are completed, or dimethyl ether is directly made into gasoline and a part of LPG is produced as a by-product, the problem will be solved.