Preparation method and device for direct phase change heat transfer type gas hydrates

Abstract

The invention relates to a direct phase change heat transfer type hydration method and a direct phase change heat transfer type hydration apparatus. Firstly, an emulsion of liquid phase change material and water is prepared, wherein a freezing point of the emulsion higher than that of water, the emulsion is cooled to obtain slurry containing solid particles of the phase change material; and then, the prepared slurry is sent to a hydrator and fully contacts with introduced small-molecule gases to finish the hydration. Heat produced during the hydration process is removed in a direct phase change heat transfer way by utilizing the characteristic that a solid absorbs heat when being melt and matching melt heat with hydration heat. The method is suitable for separation and storage of the gases. The apparatus comprises a disperser (7), a container (5), a pressure pump (3), a heat exchanger (2), a hydrator (1) and a regulating valve (6). A temperature variation of the hydrator designed by the invention is maintained within 1 DEG C. A temperature rise in the hydrator is restrained, so that the hydration rate is significantly increased.

Description

Technical field

[0001] The invention belongs to the fields of energy and chemical industry, and especially for the storage and separation of small molecular gases such as natural gas, a direct phase change thermal hydration method and device are proposed. Background technique

[0002] Certain small molecular gases, such as methane, ethane, carbon dioxide, etc., under low temperature and high pressure conditions, will form a cage-like solid substance with water in a non-stoichiometric ratio, called gas hydrate. The study of hydrate originates from the discovery of a large amount of cotton-like solids in natural gas transportation pipelines, which can block the pipeline in severe cases. In the beginning, people’s motivation was to try to prevent the formation of this kind of natural gas hydrate, but now more people want to use hydrate to store natural gas, capture carbon dioxide in the air, and separate mixed gas. However, all these applications are limited by a too low hydration ...

Examples

Embodiment 1

[0036] Used devices such as figure 1 Shown: the disperser 7 is used for high-speed shearing of a mixed liquid containing phase change materials, surfactants, nucleating agents and water. Fix the disperser 7 on the top of the container 5 with a bracket, adjust the height of the disperser 7 so that the cutter head of the disperser 7 extends into the liquid in the container 5, and the liquid in the container 5 passes under the action of the pressure pump 3. The suction line 10 and the discharge line 11 are transported to the heat exchanger 2. The heat exchanger 2 is connected to the hydrator 1 through the inlet line 12, and the bottom of the hydrator 1 is provided with an air inlet, and the hydrated gas passes through the air inlet line 13 Enter the hydrator 1, which is equipped with a stirrer 4, which is mainly used to strengthen the mass transfer between gas and liquid and enhance the phase change heat transfer in the hydration process, and try to avoid the formation of hydrate ...

Embodiment 2

[0040] Select the phase change material normal carbon tetradecane, deionized water, surfactant span60 and tween60 and the nucleating agent normal octadecane to make the phase change material 35wt%, water 62.2wt%, surfactant 2wt%, The nucleating agent is a 0.8wt% mixed liquid, in which the mass ratio of span60 and tween60 is 1:2, and this liquid mixing process is completed in container 5. Then the container 5 containing the mixed solution was placed in a constant temperature water bath at 30°C for half an hour. After the temperature stabilized, the disperser 7 was used for processing at 10000 rpm for one hour to obtain an emulsion of the phase change material and water. The emulsion is sent to the heat exchanger 2 by the pressure pump 3 through the suction line 10 and the discharge line 11 at a flow rate of 4 mL / min. After cooling, the phase change material droplets in the emulsion solidify to form a solid particle dispersed in water. Slurry. The slurry enters the hydrator 1 th...

Embodiment 3

[0042] Select the phase change material normal carbon tetradecane and normal carbon pentadecane, deionized water, surfactant span60 and tween 60 and nucleating agent normal octadecane to make the phase change material 60wt%, water 35wt%, surface A mixture of 4wt% active agent and 1wt% nucleating agent, in which the mass ratio of n-carbon tetradecane and n-carbon pentadecane is 4:1, and the mass ratio of span60 and tween60 is 1:2. This liquid mixing process Finished in container 5. Then the container 5 containing the mixed solution was placed in a constant temperature water bath at 30°C for half an hour, and after the temperature stabilized, the disperser 7 was used for processing at a speed of 30,000 rpm for 20 minutes to obtain an emulsion of phase change material and water. The emulsion is sent to the heat exchanger 2 by the pressure pump 3 through the suction line 10 and the discharge line 11 at a flow rate of 2.5 mL / min. After cooling, the phase change material droplets in ...

Technical field

[0001] The invention belongs to the fields of energy and chemical industry, and especially for the storage and separation of small molecular gases such as natural gas, a direct phase change thermal hydration method and device are proposed. Background technique

[0002] Certain small molecular gases, such as methane, ethane, carbon dioxide, etc., under low temperature and high pressure conditions, will form a cage-like solid substance with water in a non-stoichiometric ratio, called gas hydrate. The study of hydrate originates from the discovery of a large amount of cotton-like solids in natural gas transportation pipelines, which can block the pipeline in severe cases. In the beginning, people’s motivation was to try to prevent the formation of this kind of natural gas hydrate, but now more people want to use hydrate to store natural gas, capture carbon dioxide in the air, and separate mixed gas. However, all these applications are limited by a too low hydration ...

Examples

Embodiment 1

[0036] Used devices such as figure 1 Shown: the disperser 7 is used for high-speed shearing of a mixed liquid containing phase change materials, surfactants, nucleating agents and water. Fix the disperser 7 on the top of the container 5 with a bracket, adjust the height of the disperser 7 so that the cutter head of the disperser 7 extends into the liquid in the container 5, and the liquid in the container 5 passes under the action of the pressure pump 3. The suction line 10 and the discharge line 11 are transported to the heat exchanger 2. The heat exchanger 2 is connected to the hydrator 1 through the inlet line 12, and the bottom of the hydrator 1 is provided with an air inlet, and the hydrated gas passes through the air inlet line 13 Enter the hydrator 1, which is equipped with a stirrer 4, which is mainly used to strengthen the mass transfer between gas and liquid and enhance the phase change heat transfer in the hydration process, and try to avoid the formation of hydrate ...

Embodiment 2

[0040] Select the phase change material normal carbon tetradecane, deionized water, surfactant span60 and tween60 and the nucleating agent normal octadecane to make the phase change material 35wt%, water 62.2wt%, surfactant 2wt%, The nucleating agent is a 0.8wt% mixed liquid, in which the mass ratio of span60 and tween60 is 1:2, and this liquid mixing process is completed in container 5. Then the container 5 containing the mixed solution was placed in a constant temperature water bath at 30°C for half an hour. After the temperature stabilized, the disperser 7 was used for processing at 10000 rpm for one hour to obtain an emulsion of the phase change material and water. The emulsion is sent to the heat exchanger 2 by the pressure pump 3 through the suction line 10 and the discharge line 11 at a flow rate of 4 mL / min. After cooling, the phase change material droplets in the emulsion solidify to form a solid particle dispersed in water. Slurry. The slurry enters the hydrator 1 th...

Embodiment 3

[0042] Select the phase change material normal carbon tetradecane and normal carbon pentadecane, deionized water, surfactant span60 and tween 60 and nucleating agent normal octadecane to make the phase change material 60wt%, water 35wt%, surface A mixture of 4wt% active agent and 1wt% nucleating agent, in which the mass ratio of n-carbon tetradecane and n-carbon pentadecane is 4:1, and the mass ratio of span60 and tween60 is 1:2. This liquid mixing process Finished in container 5. Then the container 5 containing the mixed solution was placed in a constant temperature water bath at 30°C for half an hour, and after the temperature stabilized, the disperser 7 was used for processing at a speed of 30,000 rpm for 20 minutes to obtain an emulsion of phase change material and water. The emulsion is sent to the heat exchanger 2 by the pressure pump 3 through the suction line 10 and the discharge line 11 at a flow rate of 2.5 mL / min. After cooling, the phase change material droplets in ...

Images