Method for preparing gas hydrate

Abstract

The invention provides a method for preparing a gas hydrate, belonging to the field of gas storage and transportation. An internal helix groove structure is adopted for the tube pass of a reactor; a falling-film type heat exchange component is adopted for the shell pass of the reactor; after pressurized by a compressor, gas enters the reactor from a high-pressure gas inlet valve at the bottom of the reactor, then fully contacts with low-temperature and high-pressure reaction liquid and undergoes a hydration reaction with the low-temperature and high-pressure reaction liquid to generate hydrateslurry; the reactor is provided with an internal circulator for adjusting reaction residence time and hydrate morphology to realize multiphase separation; the hydrate slurry enters an intermediate storage tank for gas-slurry separation after passing through the internal circulator and then enters a separator for liquid-solid separation, separated liquid and gas are circulated back to a reaction system, and a separated product is conveyed to a refrigeration house for storage; and heat released by the reaction is removed by the refrigerating unit. By means of the method, a natural gas hydrate,a coalbed methane hydrate, a biogas hydrate and a landfill gas hydrate can be generated conveniently, efficiently and stably.

Description

technical field [0001] The invention relates to a method for preparing gas hydrates in a reactor with an endogenous force field, which belongs to the field of gas storage and transportation. The method is used for efficiently and stably preparing gas hydrates, mainly including natural gas hydrates, coalbed methane hydrates, Biogas hydrate and landfill gas hydrate, thereby improving the comprehensive utilization effect of natural gas, coal bed methane, biogas, landfill gas and other gases. Background technique [0002] Energy is the material basis of national economic development and the "blood" in the process of social and economic development. There is a close relationship between energy and social and economic development. With the rapid development of our country, the energy gap has become an important factor restricting development. In recent years, my country's social energy demand has been increasing day by day, and it has become the second largest energy consumption i...

AI Technical Summary

Problems solved by technology

Although natural gas has achieved certain results in the development of natural gas in recent years, and the understanding of natural gas has also been popularized, there are still many people who do not really enjoy the convenience brought by natural gas. The reason is that the construction of pipeline networks caused by unbalanced regional development Insufficient strength to make natural gas transport smoothly

[0010] The problem of entering the pipeline network: coalbed methane and natural gas pipeline networks are generally constructed by large state-owned enterprises, and there is a monopoly in operation. It is very difficult to transport the coalbed methane produced by other enterprises through their pipelines

In addition, coalbed methane with a methane concentration of less than 90% cannot directly enter the pipeline. It needs to undergo dehydration, desulfurization, purification, etc. to make the methane concentration reach about 95% before connecting to the pipeline network. However, the technical requirements are high and the cost is high.

[0011] Waste of energy resources in small-scale gas wells: For small-scale gas wells exploited by a single well, whether it is pipeline transportation, CNG, or LNG, there are problems of high cost and low income, which makes coalbed methane resources unable to be well utilized, and often It had to be scrapped, especially in the early stages of development, resulting in a large amount of CBM venting

[0012] Low-concentration gas emission problem: As of 2017, the total amount of gas drainage in coal mines in the country exceeded 12.8 billion cubic meters, and about 4.9 billion cubic meters of gas with a concentration above 8% could be used. More than 7.8 billion cubic meters of gas are directly emptied every year, which not only causes waste of resources, but also aggravates air pollution and greenhouse effect

[0013] (2) The use of biogas

Although some villages built ponds early, they discarded biogas slurry and biogas residues in vain, which not only wasted high-quality resources, but also caused secondary pollution to the environment.

[0015] (3) Landfill gas recovery and utilization issues

[0016] The main problems of landfill gas recovery and utilization are as follows: ① The geographical distribution of landfill sites in my country is relatively scattered; ② my country’s landfill gas utilization lacks experience in landfill gas recovery and utilization; ③ The gas production rate, gas production rate and Prediction and control technology for gas production cycle, etc., optimize landfill process, improve site gas production and stability, maximize the use of landfill gas resources and equipment, and avoid idle or idling operation of equipment; ④ Improve the technical level and energy of equipment The conversion efficiency and joint utilization efficiency, and the degree of integration of related technologies need to be improved; ⑤ my country's landfill gas utilization has not yet formed a corresponding industrialization foundation and business operation mode, and it is necessary to learn from foreign advanced landfill gas utilization industrialization experience and business operation mode , establish a modern landfill gas utilization industry and business operation model

For the preparation of hydrates in a smooth tube, since the formation of hydrates is carried out in a low-temperature, high-pressure environment, during the process of removing the reaction heat, the temperature of the inner wall of the reaction tube is lower than the temperature inside the tube, resulting in the formation of hydrates on the wall The rate is faster, and at the same time, due to the existence of the velocity boundary layer, the hydrate on the wall is attached, which further inhibits the formation of hydrate in the reactor, so that the equipment cannot continuously and effectively generate hydrate

[0026] To sum up, these technologies all have some weaknesses, such as: low heat transfer efficiency, complex process, difficult to control, unstable and continuous operation, etc. Therefore, it is necessary to develop an efficient, stable and applicable gas hydrate generation method for industrial production and installation

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