A hydrate-promoting composition, its use and a method for storing and transporting gas

Abstract

The present application relates to natural gas safe storage and transportation technical field, specifically relates to a kind of hydrate promoting composition and its application and gas storage and transportation method.The composition contains neutralizing agent and hydrate formation promoter;Wherein, the neutralizing agent contains component A;The component A is selected from one or more than two of methylcyclohexane, methyl tert-butyl ether, oxidized cyclopentene and tetrahydrofuran-3-ketone.The hydrate promoting composition can still improve the generation rate of hydrate, gas storage capacity and recovery rate in hydrate decomposition recovery stage under the adverse conditions that alcohol and / or salt exist in water source.

Description

Technical Field

[0001] This invention relates to the field of natural gas safe storage and transportation technology, specifically to a hydrate promoting composition and its application, as well as a gas storage and transportation method. Background Technology

[0002] Natural gas, as one of the most widely distributed energy sources, is characterized by stable combustion, high calorific value, and cleanliness, making it the most ideal and practical clean and efficient energy source currently available. Among the various methods of natural gas storage and transportation, the solid hydrate method, which utilizes water to form crystalline compounds from natural gas for storage and transportation, has become a key area of ​​research due to its advantages such as large theoretical gas storage capacity, relatively mild reaction conditions, and relatively safe process.

[0003] Hydrate gas storage technology suffers from drawbacks such as slow formation rate, unsatisfactory actual storage capacity, and easy decomposition during transportation. Simple physical methods like pressurization and cooling are insufficient to address these issues, thus chemical additives are commonly used for improvement. Chemical additives are generally classified into thermodynamic promoters and kinetic promoters. Thermodynamic promoters improve the thermodynamic conditions for hydrate formation, shifting the phase equilibrium towards a more favorable formation direction. Kinetic promoters accelerate the nucleation and growth rate of hydrates, increasing their storage capacity. In practical industrial applications, the amount of pure water required for hydrate formation is extremely large. If ordinary industrial water or circulating water is used, substances such as alcohols or salts may significantly inhibit hydrate formation. Currently, research on promoters for solid hydrate gas storage technology largely focuses on pure water and natural gas as reaction raw materials; promoters for reactants containing alcohols or similar substances are rarely reported. Summary of the Invention

[0004] Currently, reagents for the hydrate formation stage all use pure water as the water source for hydrate formation. There is little research on cases where the water source contains substances such as alcohols. The presence of alcohol salts further exacerbates the thermodynamic and kinetic conditions for hydrate formation. Therefore, the purpose of this invention is to overcome the adverse effects of the presence of alcohols and salts on the storage and transportation of natural gas containing hydrates, as well as problems such as slow hydrate formation rates, unsatisfactory actual gas storage capacity, and easy decomposition during transportation. This invention provides a hydrate-promoting composition, its application, and a method for gas storage and transportation.

[0005] To achieve the above objectives, the present invention provides a hydrate-promoting composition, wherein the composition contains a neutralizing agent and a hydrate formation promoter;

[0006] The neutralizing agent contains component A;

[0007] Component A is selected from one or more of methylcyclohexane, methyl tert-butyl ether, cyclopentene oxide, and tetrahydrofuran-3-one.

[0008] Preferably, the neutralizing agent further contains synergistic components;

[0009] Preferably, the synergistic component is tetrabutylammonium bromide;

[0010] Preferably, the weight ratio of component A to synergistic component is 1:0.1-5.

[0011] Preferably, the hydrate formation promoter is an amino acid-based promoter;

[0012] Preferably, the hydrate formation promoter is selected from one or more of leucine, valine, and phenylalanine.

[0013] Preferably, the weight ratio of the neutralizing agent to the hydrate formation promoter is 1:0.01-0.5.

[0014] Preferably, the composition further comprises a dispersant;

[0015] Preferably, the dispersant is metal oxide nanoparticles;

[0016] Preferably, the dispersant is selected from one or more of CuO nanoparticles, ZnO nanoparticles, Al2O3 nanoparticles and MgO nanoparticles.

[0017] Preferably, the weight ratio of neutralizing agent to dispersant is 1:0.005-0.1.

[0018] Preferably, the composition further contains an auxiliary agent;

[0019] Preferably, the auxiliary agent is an anionic surfactant;

[0020] Preferably, the auxiliary agent is selected from one or more of sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and polyethylene glycol.

[0021] Preferably, the weight ratio of the neutralizing agent to the auxiliary agent is 1:0.01-0.2.

[0022] Preferably, the composition further comprises a stabilizer;

[0023] Preferably, the stabilizer is lecithin.

[0024] Preferably, the weight ratio of neutralizing agent to stabilizer is 1:0.001-0.1.

[0025] A second aspect of the present invention provides the use of the composition described above in the hydrate method for storing and transporting gases.

[0026] A third aspect of the present invention provides a gas storage and transportation method, the method comprising contacting a gas with the aforementioned hydrate-promoting composition in an aqueous system under hydrate formation conditions.

[0027] Preferably, the aqueous system contains alcohol and / or salt;

[0028] Preferably, the aqueous system contains an alcohol, and the weight ratio of alcohol to water is ≤20%;

[0029] Preferably, the aqueous system contains salt, and the weight ratio of salt to water is ≤10%.

[0030] Preferably, the water-bearing system is wastewater from the gas field gathering station.

[0031] Preferably, the hydrate formation conditions include a temperature of 0-10℃ and a pressure of 5-7 MPa.

[0032] This invention discloses a hydrate-promoting composition that can still improve the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage, even under harsh conditions where alcohols and / or salts are present in the water source. Based on this hydrate-promoting composition, wastewater (such as sewage from gas field gathering stations) can be used as a water source to generate hydrates for natural gas storage and transportation. Therefore, this invention is of great significance for the development of hydrate safe storage theory and corresponding gas storage technology. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the performance evaluation device used in this invention.

[0034] Explanation of reference numerals in the attached figures

[0035] 1. Gas cylinder 2. First temperature sensor

[0036] 3 top valves and 4 pressure sensors

[0037] 5. Air bath 6. Sapphire reactor

[0038] 7 Magnets 8 Data Acquisition System

[0039] 9. Stirrer; 10. Second temperature sensor Detailed Implementation

[0040] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0041] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0042] Furthermore, terms such as "upper," "lower," "inner," and "outer" indicating orientation or positional relationships are based on the orientation or relative positional relationships shown in the accompanying drawings. They are merely simplified descriptions for the convenience of describing this application and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0043] Furthermore, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0044] In one aspect, the present invention provides a hydrate-promoting composition, the composition comprising a neutralizing agent and a hydrate formation promoter;

[0045] The neutralizing agent contains component A;

[0046] Component A is selected from one or more of methylcyclohexane, methyl tert-butyl ether, cyclopentene oxide, and tetrahydrofuran-3-one.

[0047] In a preferred embodiment, the neutralizing agent further contains a synergistic component. The addition of the synergistic component helps to promote the effect of component A and further reduces the adverse effects of alcohols and salts on hydrate formation.

[0048] More preferably, the synergistic component is tetrabutylammonium bromide.

[0049] In a preferred embodiment, the weight ratio of component A to the synergistic component is 1:0.1-5; specifically, it can be 1:0.1, 1:0.2, 1:0.4, 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5 or 1:5.

[0050] In this invention, the combination of a hydrate formation promoter and a neutralizing agent not only mitigates the adverse effects of alcohols and salts present in water on hydrate formation but also improves the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage. Preferably, the hydrate formation promoter is an amino acid-based promoter; more preferably, the hydrate formation promoter is selected from one or more of leucine, valine, and phenylalanine.

[0051] To further improve the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage, the dosage of neutralizing agent and hydrate formation promoter can be reasonably controlled. In a preferred embodiment, the weight ratio of neutralizing agent to hydrate formation promoter is 1:0.01-0.5, more preferably 1:0.01-0.1.

[0052] In specific embodiments, the weight ratio of the neutralizing agent to the hydrate formation promoter can be 1:0.01, 1:0.02, 1:0.03, 1:0.05, 1:0.06, 1:0.1, 1:0.12, 1:0.15, 1:0.16, 1:0.18, 1:0.2, 1:0.25, 1:0.28, 1:0.3, 1:0.32, 1:0.35, 1:0.37, 1:0.4, 1:0.42, 1:0.45, 1:0.48, or 0.5.

[0053] In this invention, to further improve the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage, in a preferred embodiment, the composition further contains a dispersant. The dispersant can enhance gas-liquid interface mass transfer and provide nucleation sites. More preferably, the dispersant is a metal oxide nanoparticle.

[0054] More preferably, the dispersant is selected from one or more of CuO nanoparticles, ZnO nanoparticles, Al2O3 nanoparticles and MgO nanoparticles.

[0055] To further improve the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage, the dosage of neutralizing agent and dispersant can be rationally controlled. In a preferred embodiment, the weight ratio of neutralizing agent to dispersant is 1:0.001-0.1, more preferably 1:0.005-0.01.

[0056] In specific embodiments, the weight ratio of the neutralizing agent to the dispersant can be 1:0.005, 1:0.006, 1:0.007, 1:0.008, 1:0.009, 1:0.01, 1:0.015, 1:0.02, 1:0.025, 1:0.03, 1:0.04, 1:0.045, 1:0.05, 1:0.055, 1:0.06, 1:0.065, 1:0.07, 1:0.075, 1:0.08, 1:0.085, 1:0.09, 1:0.095, or 1:0.1.

[0057] In a preferred embodiment, the composition further comprises an adjuvant. The adjuvant can promote the dissolution of the neutralizing agent and the hydrate formation promoter. More preferably, the adjuvant is an anionic surfactant.

[0058] More preferably, the auxiliary agent is selected from one or more of sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and polyethylene glycol.

[0059] In a specific implementation, the molecular weight of polyethylene glycol can be 300-600.

[0060] To further improve the hydrate formation rate, gas storage capacity, and recovery rate during the hydrate decomposition and recovery stage, the dosage of neutralizing agent and auxiliary agent can be rationally controlled. In a preferred embodiment, the weight ratio of neutralizing agent to auxiliary agent is 1:0.01-0.2, more preferably 1:0.01-0.05.

[0061] In specific embodiments, the weight ratio of the neutralizing agent to the auxiliary agent can be 1:0.01, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.08, 1:0.1, 1:0.11, 1:0.12, 1:0.14, 1:0.15, 1:0.16, 1:0.18, or 1:0.2.

[0062] In a preferred embodiment, the composition further contains a stabilizer to further reduce the decomposition of hydrates. More preferably, the stabilizer is lecithin.

[0063] In a preferred embodiment, the weight ratio of the neutralizing agent to the stabilizer is 1:0.001-0.1, more preferably 1:0.003-0.01.

[0064] In specific embodiments, the weight ratio of the neutralizing agent to the stabilizer can be 1:0.001, 1:0.005, 1:0.01, 1:0.015, 1:0.02, 1:0.025, 1:0.03, 1:0.035, 1:0.04, 1:0.045, 1:0.05, 1:0.055, 1:0.06, 1:0.07, 1:0.075, 1:0.08, 1:0.085, 1:0.09, or 1:0.1.

[0065] A second aspect of the present invention provides the use of the composition described above in the hydrate method for storing and transporting gases.

[0066] When applying the hydrate promoting composition of the present invention, the components are mixed together before use.

[0067] A third aspect of the present invention provides a gas storage and transportation method, the method comprising contacting a gas with the aforementioned hydrate-promoting composition in an aqueous system under hydrate formation conditions.

[0068] The hydrate-promoting composition of this invention can still improve the hydrate formation rate, gas storage capacity, and recovery rate of the hydrate decomposition and recovery stage, even under harsh conditions where alcohols and / or salts are present in the water source (i.e., the aqueous system). Preferably, the aqueous system contains alcohols and / or salts.

[0069] More preferably, when the aqueous system contains alcohol, the weight ratio of alcohol to water is ≤20%.

[0070] In a preferred embodiment, the alcohol may be a fatty alcohol, specifically one or more of methanol, ethanol, and ethylene glycol.

[0071] More preferably, when the aqueous system contains salt, the weight ratio of salt to water is ≤10%.

[0072] In a preferred embodiment, the salt is an inorganic salt, specifically one or more of sodium chloride, potassium chloride, calcium chloride, and sodium sulfate.

[0073] In one specific implementation, the aqueous system can be wastewater from a gas field gathering station.

[0074] In a preferred embodiment, the hydrate formation conditions include a temperature of 0-10°C and a pressure of 5-7 MPa.

[0075] In this invention, the gas from which hydrates are to be formed can be a single gas requiring storage and transportation, such as methane, propane, carbon dioxide, and hydrogen, or a mixture of gases, such as natural gas. The aqueous system can be a simple aqueous phase or an oil-water two-phase system.

[0076] In this invention, unless otherwise specified, all pressures are gauge pressures.

[0077] Wastewater from gas gathering stations is characterized by large volume, complex composition, high alcohol content, and high mineralization, making it difficult to recover and reuse. Based on the hydrate-promoting composition described in this invention, wastewater from gas gathering stations can be used as a water source to generate hydrates for natural gas storage and transportation, thereby enabling the resource utilization of wastewater from gas gathering stations.

[0078] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.

[0079] In the following examples and comparative examples, the following are used: Figure 1 The performance evaluation device shown was used in the experiment. The working volume of this device is 50 cm³. 3 The maximum working pressure is 15MPa, and the working temperature range is 183K-423K.

[0080] See also Figure 1 The performance evaluation device shown includes: gas cylinder 1, first temperature sensor 2, top valve 3, pressure sensor 4, high and low temperature test chamber 5, sapphire reactor 6, magnet 7, data acquisition system 8, stir bar 9, and second temperature sensor 10.

[0081] Among them, gas cylinder 1 is connected to sapphire reactor 6 via pipeline, responsible for providing the methane gas and pressure required for hydrate formation; first temperature sensor 2 is connected to the top of sapphire reactor 6 for real-time monitoring of the reactor's internal temperature; pressure sensor 4 is connected to the top of sapphire reactor 6 for real-time monitoring of the reactor's internal pressure; top valve 3 is responsible for controlling the entry and exit of gas inside the reactor; magnet 7 is used to control the stir bar 9 inside the reactor to provide impact stirring; sapphire reactor 6 is a fully transparent sapphire reactor, located inside high and low temperature test chamber 5; second temperature sensor 10 is connected to high and low temperature test chamber 5 for monitoring the internal temperature of high and low temperature test chamber 5; data acquisition system 8 is a computer-based automatic data acquisition system for recording system temperature, pressure, and reaction time.

[0082] The specific steps for conducting performance evaluation experiments using the aforementioned performance evaluation device are as follows:

[0083] (1) Clean the reaction vessel, add the test solution (about 10 mL), install the reaction vessel, evacuate the system, and purge with methane gas 3 times;

[0084] (2) Set the system temperature to the experimental temperature. When the temperature inside the reactor reaches the preset value and remains stable for 1 hour, introduce methane gas to the experimental pressure, turn on the impact stirring, observe the macroscopic morphological changes in the system, and the computer data acquisition system records the temperature and pressure changes of the system.

[0085] (3) When white hydrate particles appear in the system, record the time as the hydrate induction time, and record the system pressure at 30 min and 120 min of the reaction.

[0086] (4) After 120 min, the system pressure was basically stable and the hydrate formation process ended. The experimental temperature was adjusted to 25℃ to decompose the hydrate, and the macroscopic morphological changes of the system during the decomposition process were observed.

[0087] The test solution was prepared by mixing laboratory-prepared water sample and the sample to be tested. The laboratory-prepared water sample was prepared by mixing pure water, methanol and NaCl, wherein the weight ratio of methanol to water was 20% and the weight ratio of NaCl to water was 10%.

[0088] The purity of the methane gas is 99.99%.

[0089] The calculation method for gas storage capacity during the solid hydrate formation stage is as follows:

[0090] At the moment when methane hydrate first appears, the molar molecular weight of methane in the system is obtained from the real gas law:

[0091]

[0092] At the end of the generation phase, the molar molecular weight of the gas in the system is obtained from the real gas law:

[0093]

[0094] Where: n0 and n e The initial methane consumption and the final methane consumption are given in mol; P0 and P e The pressures at the initial moment and the end of the generation phase of the system are Pa and V. g The volume of the gas phase in the reactor is m. 3 Z0 and Z e R is the gas compressibility coefficient of the system at the beginning and end of the hydrate formation stage, calculated by the Penn-Robinson equation; R is the gas constant, J / (mol*K); T is the experimental set temperature, K.

[0095] The methane gas consumption for hydrate formation in the hydrate formation stage system is:

[0096] Δn=n0-n e

[0097] The gas storage capacity during the hydrate formation stage is:

[0098]

[0099] in, This represents the molar amount of water in the system solution.

[0100] Example 1

[0101] This embodiment provides a hydrate promoting composition S1, which is obtained by mixing methylcyclohexane, tetrabutylammonium bromide, leucine, CuO nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:0.05:0.01:0.05:0.005; that is, the weight ratio of component A to synergistic component is 1:0.5, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.033:0.007:0.033:0.003.

[0102] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S1 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S1 was 5% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 14.2 min.

[0103] From the appearance of hydrate particles in the system, the system pressure was 5629 kPa and 5221 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0405 mol / mol.

[0104] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0105] Example 2

[0106] This embodiment provides a hydrate promoting composition S2, which is obtained by mixing cyclopentene oxide, tetrabutylammonium bromide, valine, ZnO nanoparticles, hexadecyltrimethylammonium bromide, and lecithin in a weight ratio of 1:0.1:0.03:0.02:0.05:0.01, that is, the weight ratio of component A to synergistic component is 1:0.1, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.027:0.018:0.045:0.009.

[0107] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S2 was added to the laboratory-prepared water sample to obtain the test solution. The amount of hydrate promoting composition S2 was 5% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 17.9 min.

[0108] From the appearance of hydrate particles in the system, the system pressure was 5729 kPa and 5327 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0351 mol / mol.

[0109] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0110] Example 3

[0111] This embodiment provides a hydrate promoting composition S3, which is obtained by mixing tetrahydrofuran-3-one, tetrabutylammonium bromide, phenylalanine, MgO nanoparticles, polyethylene glycol, and lecithin in a weight ratio of 1:0.8:0.03:0.02:0.08:0.01, that is, the weight ratio of component A to synergistic component is 1:0.8, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.017:0.011:0.044:0.006.

[0112] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A test solution was obtained by adding hydrate promoting composition S3 to a laboratory-prepared water sample. The amount of hydrate promoting composition S3 was 5% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 15.3 min.

[0113] From the appearance of hydrate particles in the system, the system pressure was 5729 kPa and 5217 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0407 mol / mol.

[0114] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0115] Example 4

[0116] This embodiment provides a hydrate promoting composition S4, which is obtained by mixing methyl tert-butyl ether, tetrabutylammonium bromide, leucine, Al2O3 nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:0.05:0.01:0.05:0.005, that is, the weight ratio of component A to synergistic component is 1:05, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.033:0.007:0.033:0.003.

[0117] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S4 was added to the laboratory-prepared water sample to obtain the test solution. The amount of hydrate promoting composition S4 was 8% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 11.9 min.

[0118] From the appearance of hydrate particles in the system, the system pressure was 5529 kPa and 5172 kPa at 30 min and 120 min, respectively, and the calculated gas storage capacity was 0.0430 mol / mol.

[0119] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0120] Example 5

[0121] This embodiment provides a hydrate promoting composition S5, which is obtained by mixing methylcyclohexane, tetrabutylammonium bromide, valine, nano-CuO particles, hexadecyltrimethylammonium bromide, and lecithin in a weight ratio of 1:1:0.02:0.02:0.07:0.003, that is, the weight ratio of component A to synergistic component is 1:1, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.01:0.01:0.035:0.0015.

[0122] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S5 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S5 was 8% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 12.1 min.

[0123] From the appearance of hydrate particles in the system, the system pressure was 5483 kPa and 5085 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0475 mol / mol.

[0124] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0125] Example 6

[0126] This embodiment provides a hydrate-promoting composition S6, which is obtained by mixing cyclopentene oxide, tetrabutylammonium bromide, phenylalanine, ZnO nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.3:0.04:0.01:0.06:0.02; that is, the weight ratio of component A to synergistic component is 1:0.3, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.031:0.008:0.0462:0.0153.

[0127] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S6 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S6 was 8% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 10.7 min.

[0128] From the appearance of hydrate particles in the system, the system pressure was 5608 kPa and 5126 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0454 mol / mol.

[0129] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0130] Example 7

[0131] This embodiment provides a hydrate-promoting composition S7, which is obtained by mixing methylcyclohexane, tetrabutylammonium bromide, leucine, MgO nanoparticles, polyethylene glycol, and lecithin in a weight ratio of 1:0.4:0.07:0.01:0.05:0.005; that is, the weight ratio of component A to synergistic component is 1:0.4, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.05:0.007:0.036:0.0036.

[0132] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S7 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S7 was 10% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 9.3 min.

[0133] From the appearance of hydrate particles in the system, the system pressure was 5385 kPa and 4938 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0549 mol / mol.

[0134] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0135] Example 8

[0136] This embodiment provides a hydrate promoting composition S8, which is obtained by mixing cyclopentene oxide, tetrabutylammonium bromide, leucine, CuO nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.8:0.1:0.01:0.05:0.005, that is, the weight ratio of component A to synergistic component is 1:0.8, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.056:0.006:0.028:0.0028.

[0137] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. The test solution was obtained by adding hydrate promoting composition S8 to the laboratory water sample. The amount of hydrate promoting composition S8 was 10% of the weight of water in the laboratory water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 10.2 min.

[0138] From the appearance of hydrate particles in the system, the system pressure was 5429 kPa and 5007 kPa at 30 min and 120 min, respectively, and the calculated gas storage capacity was 0.0514 mol / mol.

[0139] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0140] Example 9

[0141] This embodiment provides a hydrate promoting composition S9, which is obtained by mixing methyl tert-butyl ether, tetrabutylammonium bromide, leucine, Al2O3 nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:0.05:0.01:0.05:0.01, that is, the weight ratio of component A to synergistic component is 1:0.5, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.033:0.007:0.033:0.007.

[0142] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. The test solution was obtained by adding hydrate promoting composition S9 to the laboratory water sample. The amount of hydrate promoting composition S9 was 10% of the weight of water in the laboratory water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 9.8 min.

[0143] From the appearance of hydrate particles in the system, the system pressure was 5430 kPa and 4962 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0537 mol / mol.

[0144] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0145] Example 10

[0146] This embodiment provides a hydrate promoting composition S10, which is obtained by mixing cyclopentene oxide, tetrabutylammonium bromide, valine, MgO nanoparticles, hexadecyltrimethylammonium bromide, and lecithin in a weight ratio of 1:0.3:0.03:0.01:0.1:0.01, that is, the weight ratio of component A to synergistic component is 1:0.3, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.023:0.008:0.077:0.008.

[0147] In this embodiment, the performance evaluation device described above was used to evaluate the performance. A hydrate promoting composition S10 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S10 was 15% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 7.4 min.

[0148] From the appearance of hydrate particles in the system, the system pressure was 5427 kPa and 4849 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0594 mol / mol.

[0149] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0150] Example 11

[0151] This embodiment provides a hydrate promoting composition S11, which is obtained by mixing tetrahydrofuran-3-one, tetrabutylammonium bromide, leucine, nano-ZnO particles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:0.05:0.02:0.05:0.005, that is, the weight ratio of component A to synergistic component is 1:0.5, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.033:0.013:0.033:0.003.

[0152] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S11 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S11 was 15% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 6.8 min.

[0153] From the appearance of hydrate particles in the system, the system pressure was 5329 kPa and 4857 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0590 mol / mol.

[0154] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0155] Example 12

[0156] This embodiment provides a hydrate-promoting composition S12, which is obtained by mixing methylcyclohexane, methyl tert-butyl ether, tetrabutylammonium bromide, leucine, CuO nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:1:0.5:0.1:0.04:0.01:0.01; that is, the weight ratio of component A to synergistic component is 1:0.25, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.04:0.016:0.004:0.004.

[0157] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S12 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S12 was 15% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 5.7 min.

[0158] From the appearance of hydrate particles in the system, the system pressure was 5402 kPa and 4937 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0550 mol / mol.

[0159] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0160] Example 13

[0161] This embodiment provides a hydrate promoting composition S13, which is obtained by mixing cyclopentene oxide, tetrahydrofuran-3-one, tetrabutylammonium bromide, leucine, Al2O3 nanoparticles, hexadecyltrimethylammonium bromide, and lecithin in a weight ratio of 0.3:0.7:0.3:0.05:0.05:0.05:0.005, that is, the weight ratio of component A to synergistic component is 1:0.3, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.038:0.038:0.038:0.0038.

[0162] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S13 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S13 was 20% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 3.9 min.

[0163] From the appearance of hydrate particles in the system, the system pressure was 5408 kPa and 4746 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0646 mol / mol.

[0164] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0165] Example 14

[0166] This embodiment provides a hydrate promoting composition S14, which is obtained by mixing tetrahydrofuran-3-one, tetrabutylammonium bromide, phenylalanine, CuO nanoparticles, polyethylene glycol, and lecithin in a weight ratio of 1:0.5:0.08:0.01:0.1:0.01, that is, the weight ratio of component A to synergistic component is 1:0.5, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.053:0.007:0.067:0.007.

[0167] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S14 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S14 was 20% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 4.1 min.

[0168] From the appearance of hydrate particles in the system, the system pressure was 5389 kPa and 4784 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0627 mol / mol.

[0169] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0170] Example 15

[0171] This embodiment provides a hydrate promoting composition S15, which is obtained by mixing methylcyclohexane, tetrabutylammonium bromide, leucine, MgO nanoparticles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:0.05:0.02:0.05:0.005, that is, the weight ratio of component A to synergistic component is 1:0.5, and the weight ratio of neutralizer, hydrate formation promoter, dispersant, auxiliary agent, and stabilizer is 1:0.033:0.013:0.033:0.003.

[0172] In this embodiment, the above-mentioned performance evaluation device was used for performance evaluation. A hydrate promoting composition S15 was added to the laboratory-prepared water sample to obtain a test solution. The amount of hydrate promoting composition S15 was 20% of the weight of water in the laboratory-prepared water sample. The experimental pressure was 6.0 MPa and the experimental temperature was 0.5℃. It was found through the sapphire reactor that the hydrate induction time was 3.7 min.

[0173] From the appearance of hydrate particles in the system, the system pressure was 5418 kPa and 4754 kPa at 30 min and 120 min respectively, and the calculated gas storage capacity was 0.0642 mol / mol.

[0174] After the hydrate is completely formed, heating will decompose the hydrate. Observation from the reaction vessel shows that almost no bubbles are generated during the hydrate decomposition process, which proves that the methane in the system can be successfully recovered.

[0175] Comparative Example 1

[0176] This comparative example does not use a accelerator; instead, it uses laboratory-prepared water samples directly for hydrate formation. The experimental temperature was set at 0.5℃. After the temperature inside the reactor stabilized, methane gas was introduced to 6.0 MPa, and the hydrate formation was observed.

[0177] Observations from the sapphire reactor showed that no hydrates were formed within 12 hours of gas introduction, and the system pressure was 5938 kPa at 720 minutes.

[0178] Comparative Example 2

[0179] This comparative example provides a composition D2, which is obtained by mixing leucine, nano-CuO particles, sodium dodecyl sulfate, and lecithin in a weight ratio of 1:0.5:2:0.5.

[0180] In this embodiment, the performance evaluation device described above is used to evaluate the performance. Composition D2 is added to the laboratory-prepared water sample to obtain the test solution. The amount of composition D2 is 2% of the weight of water in the laboratory-prepared water sample. The experimental temperature is set to 0.5℃. After the temperature inside the reactor stabilizes, methane gas is introduced to 6.0MPa, and the formation of hydrates is observed.

[0181] Observations from the sapphire reactor showed that no hydrates were formed within 12 hours of gas introduction, and the system pressure was -5954 kPa at 720 minutes.

[0182] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A hydrate-promoting composition, characterized in that, The composition contains a neutralizing agent, a hydrate formation promoter, a synergistic component, a dispersant, an auxiliary agent, and a stabilizer; The neutralizing agent contains component A; Component A is selected from one or more of methylcyclohexane, methyl tert-butyl ether, cyclopentene oxide, and tetrahydrofuran-3-one; The synergistic component is tetrabutylammonium bromide; The hydrate formation promoter is an amino acid-type promoter; The dispersant is metal oxide nanoparticles; The auxiliary agent is an anionic surfactant; The stabilizer is lecithin; The weight ratio of component A to synergistic component is 1:0.1-5, the weight ratio of neutralizer to hydrate formation promoter is 1:0.01-0.5, the weight ratio of neutralizer to dispersant is 1:0.005-0.1, the weight ratio of neutralizer to auxiliary agent is 1:0.01-0.2, and the weight ratio of neutralizer to stabilizer is 1:0.001-0.

1.

2. The hydrate-promoting composition according to claim 1, characterized in that, The hydrate formation promoter is selected from one or more of leucine, valine, and phenylalanine.

3. The hydrate-promoting composition according to claim 1, characterized in that, The dispersant is selected from one or more of CuO nanoparticles, ZnO nanoparticles, Al2O3 nanoparticles, and MgO nanoparticles.

4. The hydrate-promoting composition according to claim 1, characterized in that, The auxiliary agent is selected from sodium dodecyl sulfate.

5. The use of the composition according to any one of claims 1-4 in the hydrate method for storing and transporting gases.

6. A method for storing and transporting a gas, characterized in that, The method includes contacting a gas in an aqueous system with the hydrate-promoting composition of any one of claims 1-4 under hydrate-forming conditions.

7. The method according to claim 6, characterized in that, The amount of the hydrate promoting composition is 1-20% of the weight of water in the aqueous system.

8. The method according to claim 6, characterized in that, The aqueous system contains alcohol and / or salt.

9. The method according to claim 8, characterized in that, The aqueous system contains alcohol, and the weight ratio of alcohol to water is ≤20%.

10. The method according to claim 8, characterized in that, The aqueous system contains salt, and the weight ratio of salt to water is ≤10%.

11. The method according to any one of claims 8-10, characterized in that, The water-bearing system consists of wastewater from the gas field's gas gathering station.

12. The method according to any one of claims 8-10, characterized in that, The conditions for hydrate formation include a temperature of 0-10℃ and a pressure of 5-7MPa.

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