Direct large-scale industrialization of the hottes

2022-08-26
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The direct large-scale industrialization of natural gas into ethylene has become a reality

there are two routes for the production of ethylene from natural gas (the main component is methane): direct method and indirect method. Compared with the tedious process of indirect method, direct method can convert methane into ethylene in only one step, which has high economic value and is very attractive

the efforts of the chemical industry for more than 30 years have finally become a reality - natural gas with rich reserves and low prices can be directly converted into ethylene, the world's largest chemical basic raw material

recently, Siluria technology company (hereinafter referred to as Siluria company) of the United States held a grand start-up ceremony for its pilot plant in Texas, becoming the first enterprise in the world to realize the direct industrialization of natural gas into ethylene on a large scale, so as to avoid the undeveloped industry of experimental machines caused by earthquakes in the application process. The new route may bring major changes to the traditional ethylene industry with oil as raw material

Holy Grail in the chemical industry

as a basic industrial raw material, ethylene plays an important role in the petrochemical industry. Ethylene production is one of the important symbols to measure the development level of a country's petrochemical industry

except North America and the Middle East, most countries and regions in the world, including China, use naphtha as raw material to produce ethylene by steam cracking. This method not only consumes high energy, emits many greenhouse gases and costs high, but also needs to occupy expensive oil resources because the raw materials are from oil

in order to reduce oil dependence, countries have carried out research on the production of olefins from natural gas, the main component of which is methane. There are two ways to produce ethylene from natural gas: direct method and indirect method. Compared with the tedious process of indirect method, direct method can convert methane into ethylene in only one step, which has high economic value and is very attractive

however, since the selective activation and directional conversion of methane is a world-class problem, known as the "Holy Grail" of the entire chemical community, from the 1980s to the beginning of this century, the academic community has not been able to develop an industrially feasible process for direct production of ethylene from methane

The key to the breakthrough lies in the catalyst. In 2010, Siluria creatively used biological templates to accurately synthesize nanowire catalysts, used high-throughput technology to select the most suitable element composition from a large number of alternative catalysts, and developed an industrially feasible catalyst for directly preparing ethylene from methane

the catalyst can efficiently catalyze the conversion of methane to ethylene at 5 ~ 10 atmospheres under the operating temperature of 200 ℃ ~ 300 ℃ lower than that of the traditional steam cracking method, and its activity is more than 100 times that of the traditional catalyst

the reactor designed by Silvia company is divided into two parts, one part is used to convert methane into ethylene and ethane, and the other part is used to crack the by-product ethane into ethylene. The heat required for the cracking reaction comes from the heat released from the methane conversion reaction. This design enables the feed of the reactor to be either natural gas or ethane, while maximizing energy savings

promotion of oil substitution strategy

the technical advantages of the direct ethylene production process from natural gas (hereinafter referred to as the new route) developed by Silvia company are mainly reflected in five aspects: compared with the traditional naphtha cracking to ethylene, it has low cost, less greenhouse gas emissions, energy conservation and high economic value; Ethylene can be further converted into liquid fuel, further improving the economic value of the whole route; The requirements for raw materials are not harsh. Methane can come from natural gas or biomass. The oxygen source can be pure oxygen, oxygen enriched air, compressed air, etc; The existing ethylene production plant and recovery equipment can be used, and the transformation cost is low; It has important strategic value for countries rich in natural gas resources

in addition to the impact on the olefin industry, the new route will also affect the production of liquid fuels, including gasoline, diesel and aviation fuel. At the same time, Siluria company has developed the technology of producing liquid fuel from ethylene, which means that there is an additional route to produce liquid fuel from natural gas when it is installed on the vehicle. Compared with the current route based on Fischer Tropsch synthesis, this route of Siluria company does not need to go through Fischer Tropsch synthesis with high energy consumption, and only the investment cost can be saved by 25% - 30% Both ethylene and liquid fuels are traditionally produced from oil. The new route can save valuable oil resources and promote the oil substitution strategy

in June 2014, Germany Linde Group, the world's largest gas and engineering group, reached a cooperation agreement with Siluria company. The two sides will cooperate in the final amplification and verification process of this technology in a pilot plant in Texas. According to the agreement, both parties will optimize and integrate their respective technical and professional solutions into a package. Linde Group will be responsible for authorizing the use license of this package to the petrochemical industry for the reconstruction or expansion of existing ethylene plants or the construction of world-class ethylene plants. The authorization work is expected to start in the second half of 2015

in August 2014, Saudi Aramco, the world's leading integrated energy and chemical enterprise, invested in Siluria and planned to take the lead in deploying new routes in Saudi Arabia

previously, the production of ethane in the Middle East was insufficient to support new ethylene plants, so new enterprises were forced to turn to high-cost naphtha raw materials

the new route of Siluria company has quickly attracted the attention of petrochemical enterprises in the Middle East and become its potential market

not only overseas, the new route has also attracted the attention of the US government. In March, 2014, the CEO of Siluria was invited to attend and deliver a speech at the high-level 2020 energy policy forum, and was the only natural gas industry company among the invited enterprises. Subsequently, Siluria executives were invited to the White House to discuss the future energy policy of the United States with the Secretary of energy and other officials

the U.S. government has realized the strategic value of the new route to its energy and manufacturing industries, and is considering formulating policies to promote employment and economic development

experience reference

naphtha is the main raw material of ethylene in China, accounting for about 65% of the total raw materials Previously, with the sharp rise in international crude oil prices and the intensification of the contradiction between domestic supply and demand, the supply of olefin raw materials was tight, which restricted the development of the ethylene industry. It is estimated that the ethylene gap in China will reach 13.7 million tons in 2015

not only that, China has the problems of high production cost and weak competitiveness of ethylene. In 2013, the production cost of ethylene in the Middle East was only $100/ton, while the production cost of ethylene in North America was basically maintained at about $300/ton, while the cost of introducing the structure of microcomputer controlled cylinder pressure testing machine for assaying of ethylene in China was more than $900/ton

therefore, it is necessary for China to develop new ethylene production routes. In the research field of direct production of ethylene from natural gas, China has laid a good research foundation, and research institutions such as the Chinese Academy of Sciences and universities have deployed strong research forces

therefore, it is suggested that China should learn from the successful experience of the development of methanol to olefins in the 12th Five Year Plan and include the research on direct production of ethylene from natural gas in the relevant C plan of the 13th five year plan. Organize research institutions to carry out R & D cooperation with petrochemical enterprises, promote the transformation of basic research results into industrial production as soon as possible, break the current bottleneck of raw material sources in the ethylene industry, reduce production costs, and enhance the competitiveness of China's ethylene industry and downstream industries

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