Use of liquefied natural gas

② It is necessary to firmly lock in the international situation through research, attention and other means, and use investment, mergers and acquisitions and other methods to obtain the shares of LNG producers and LNG upstream gas resources. At present, China is in the beginning stage of LNG, and it is necessary to create a good policy environment. Economic interests must not be allowed to stand in the way of LNG. In order to make the development of LNG sustainable, when choosing partners, we must pay attention to the diversification of partners, which can make the technology more convenient and more conducive to development.

Research status

1. Foreign research status

Natural gas now accounts for a third of the world's energy production, and is likely to push the current popularity of oil and coal into secondary status in the near future. By 2020, natural gas will account for 45 to 50 percent of the world's energy needs. At present, the world's annual demand for natural gas exceeds 2.5×10m, and the amount entering international trade is (6250-6500) ×l0m, of which about 33% is sold in the form of LNG. According to the 20th World Gas Congress and related data, the potential demand for natural gas in the world will increase to 4×10m before 2030, and liquefied natural gas has always been a market segment product. Its consumption is growing at 10 per cent a year, with global LNG demand set to rise from 218 million tonnes in 2010 to 310 million tonnes in 2015 and 410 million tonnes by 2020. LNG demand grew 8.5% in the first half of 2011 compared with the same period last year, and 12% for the full year, mainly driven by new demand from Japan, the UK and India, as well as increased demand from traditional buyers in South Korea. It is expected that by 2015, China's natural gas supply structure will be 170 billion cubic meters of domestic gas, 90 billion cubic meters of net imports, and natural gas consumption will reach 260 billion cubic meters, accounting for the proportion of primary energy consumption will rise from the current 4% to 7% to 8%. In 2011, China's natural gas consumption was 131.3 billion cubic meters, and the proportion of natural gas in primary energy consumption is likely to increase to 10% to 15% .

In recent years, with the rapid development of the world natural gas industry, LNG has become an important part of the international natural gas trade. Compared with ten years ago, the world LNG trade volume has doubled, showing strong growth momentum. It is predicted that in 2012, the trade volume of LNG in the international market will account for 36% of the total trade volume of natural gas, and by 2020 it will reach 40% of the trade volume of natural gas and account for 15% of natural gas consumption.

Foreign liquefaction plant large scale, complex process, equipment, high investment, basically adopt step refrigeration and mixed refrigerant refrigeration process, the two types of devices are in operation, the new design is mainly mixed refrigerant refrigeration process, the main purpose of research is to reduce liquefaction energy consumption. The refrigeration process has been improved from step refrigeration to mixed refrigerant refrigeration cycle, and there are reports of a new CⅡ-2 process, which not only has the advantages of pure component cycle, such as simple, no phase separation and easy control, but also has the advantages of mixed refrigerant refrigeration cycle, such as good coordination of natural gas and refrigerant refrigeration temperature, high efficiency and less equipment .

The first industrialisation of Liquefin, an advanced new natural gas liquefaction process developed by Axens in collaboration with the French Institute of Petroleum Research (IFP), has laid the foundation for the LNG market. Its production capacity is 15%-20% higher than the general method, and the production cost is 25% lower. After Liquefin method is used, the output of each unit liquefaction unit can reach more than 600×104t/y. LNG production costs using the Liquefin process can be reduced by 25% per tonne. The main advantages of this process are the use of finned heat exchangers and thermodynamic optimization of the process, which can build a very large capacity liquefaction plant. Axens has proposed the process for use in several major regions, including the United States, Europe and Asia, and is conducting preliminary design and feasibility studies. The safety, environmental, practical and innovative features of the Liquefin process developed by IFP and Axens have recently been recognised worldwide with the Institution of Chemical Engineers' Engineering Excellence Award.

The University of Texas Engineering Experiment Station has developed a new type of natural gas liquefaction technology - GTL technology has been patented. The technology is more suitable for small-scale installations than the currently developed GTL technology and can process 30.5×104m3/d of natural gas. The GTL for the experimental station has been licensed to Synfuels. The company has built a GTL pilot plant near the A&M University campus and is currently conducting economic simulation analysis. The new process, which is much simpler than existing technologies, does not require syngas and does not require the use of oxygen in addition to generating electricity. Its economy, scale and production are different from the ordinary Fischer-Tropsch GTL process. The first industrial plant could be completed in the first half of 2004.