Combination system of rich gas separation technology and thermal separation technology

Abstract

The invention provides a rich gas separation technology and thermal separation technology combined system which comprises an absorption tower, the side part of the absorption tower is provided with a rich gas inlet, the top of the absorption tower is provided with a dry gas outlet, the dry gas outlet is connected with a thermal separator, the upper part of the absorption tower is also connected with an absorption liquid inlet through a cooler, and the upper part of the absorption tower is also connected with a hot separator. The hot separator is connected with the hot dry gas outlet; the separated purified gas flows through the hot separator, cold and hot separation of the purified gas is realized in the depressurization process, and the cold flow of the purified gas exchanges heat with the absorption liquid to reduce the temperature of the absorption liquid or the gas separation temperature so as to improve the separation efficiency of the mixed gas.

Description

Technical Field

[0001] The invention relates to the technical field of rich gas separation, and in particular to a combined system of rich gas separation technology and heat separation technology. Background Art

[0002] In the process of oil refining, gasoline and diesel are used as absorbents to absorb the heavy components (propane, pentane, etc.) in the rich gas (mixed gases such as hydrogen, methane, ethane, propane, pentane, etc.) to obtain dry gas (mainly containing hydrogen, methane, ethane, and the total volume content of propane and pentane is less than 3.0%). At present, the rich gas and the absorption liquid are cooled by natural air or circulating water, and the general absorption temperature is between 40 and 45°C. Under the condition of constant absorption pressure, the absorption temperature is an important factor affecting the absorption effect. The lower the absorption temperature, the greater the solubility of the gas solute, the faster the absorption speed, which is conducive to improving the absorption rate. In order to further improve the separation efficiency of the mixed gas, it is necessary to further reduce the temperature of the absorption liquid.

[0003] The existing rich gas separation process uses higher operating pressure and lower absorption temperature to improve separation effect and economic benefits. The operating pressure is achieved by compressing the rich gas with power equipment. In order to achieve a lower absorption temperature, in addition to conventional cooling methods such as air cooling and circulating water, it is generally necessary to rely on ammonia refrigeration, lithium bromide refrigeration and other means to further reduce the temperature.

[0004] Therefore, there is an urgent need for a combined system of rich gas separation technology and thermal separation technology that can solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a combined system of rich gas separation technology and thermal separation technology to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a combined system of rich gas separation technology and heat separation technology, comprising an absorption tower, wherein a rich gas inlet is provided on the side of the absorption tower, a dry gas outlet is provided on the top of the absorption tower, the dry gas outlet is connected to a heat separator, the upper part of the absorption tower is also connected to an absorption liquid inlet through a cooler, and the heat separator is connected to the hot dry gas outlet.

[0008] Preferably, an absorption oil outlet is provided at the bottom of the absorption tower.

[0009] Preferably, the heat separator comprises a dry gas inlet, a hot flow outlet and a cold flow outlet, the dry gas inlet is connected to the dry gas outlet, the hot flow outlet is connected to the hot dry gas outlet, and the cold flow outlet is connected to the hot dry gas outlet through the cooler.

[0010] Compared with the prior art, the present invention has achieved the following beneficial technical effects:

[0011] The present invention provides a combined system of a rich gas separation technology and a heat separation technology, comprising an absorption tower, wherein a rich gas inlet is provided on the side of the absorption tower, a dry gas outlet is provided on the top of the absorption tower, the dry gas outlet is connected to a heat separator, the upper part of the absorption tower is also connected to an absorption liquid inlet via a cooler, and the heat separator is connected to a hot dry gas outlet; the separated purified gas is allowed to flow through the heat separator, cold and hot separation of the purified gas is achieved during the pressure reduction process, and the cold flow of the purified gas is used to exchange heat with the absorption liquid to reduce the temperature of the absorption liquid or the temperature of gas separation, so as to improve the separation efficiency of the mixed gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0013] Figure 1 A schematic diagram of the structure of a combined system of a rich gas separation technology and a heat separation technology provided by the present invention. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] The purpose of the present invention is to provide a combined system of rich gas separation technology and heat separation technology to solve the problems existing in the prior art.

[0016] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] Embodiment 1:

[0018] This embodiment provides a combined system of rich gas separation technology and thermal separation technology, such as Figure 1As shown, it includes an absorption tower 3, a rich gas inlet 1 is provided on the side of the absorption tower 3, a dry gas outlet 10 is provided on the top of the absorption tower 3, the dry gas outlet 10 is connected to the heat separator 9, the upper part of the absorption tower 3 is also connected to the absorption liquid inlet 5 through the cooler 4, and the heat separator 9 is connected to the hot dry gas outlet 7.

[0019] As an embodiment, an absorption oil outlet 2 is provided at the bottom of the absorption tower 3 .

[0020] As an embodiment, the heat separator 9 includes a dry gas inlet, a hot flow outlet 8 and a cold flow outlet 6, the dry gas inlet is connected to the dry gas outlet 10, the hot flow outlet 8 is connected to the hot dry gas outlet 7, and the cold flow outlet 6 is connected to the hot dry gas outlet 7 through the cooler 4.

[0021] The present invention provides a combined system of a rich gas separation technology and a heat separation technology. The rich gas enters an absorption tower 3 and contacts with an absorption liquid. The absorption liquid absorbs heavy components in the rich gas and is discharged from the bottom of the absorption tower. The rich gas that has absorbed the medium components becomes dry gas and enters a heat separator 9 from the top of the absorption tower. The dry gas generates high-speed swirling motion in the cylindrical or conical inner cavity of the heat separator 9. Hot flow dry gas and cold flow dry gas are obtained at both ends of the cylindrical or conical cylinder, respectively. After the cold flow exchanges heat with the absorption liquid in the cooler 4, the temperature of the absorption liquid and the temperature of the absorption tower are reduced. The cold flow dry gas is mixed with the hot flow dry gas after the temperature rises to obtain hot dry gas. In the process of reducing the pressure, cold and hot separation of the purified gas is realized, and the cold flow of the purified gas is used to reduce the temperature of gas separation or the temperature of the absorption liquid to improve the separation efficiency of the mixed gas.

[0022] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A combined system of rich gas separation technology and thermal separation technology, characterized in that: The absorber comprises an absorption tower, wherein a rich gas inlet is arranged on the side of the absorption tower, a dry gas outlet is arranged on the top of the absorption tower, the dry gas outlet is connected to a heat separator, the upper part of the absorption tower is also connected to an absorption liquid inlet through a cooler, and the heat separator is connected to a hot dry gas outlet.

2. The combined system of rich gas separation technology and thermal separation technology according to claim 1, characterized in that: An absorption oil outlet is provided at the bottom of the absorption tower.

3. The combined system of rich gas separation technology and thermal separation technology according to claim 1, characterized in that: The heat separator comprises a dry gas inlet, a hot flow outlet and a cold flow outlet, the dry gas inlet is connected to the dry gas outlet, the hot flow outlet is connected to the hot dry gas outlet, and the cold flow outlet is connected to the hot dry gas outlet through the cooler.

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