阅读说明：本技术 一种常温提取超高纯度氦气的方法及生产装置 (Method for extracting ultra-high purity helium gas at normal temperature and production device ) 是由 李保军 贺高红 范瑛琦 于 2020-12-31 设计创作，主要内容包括：一种常温提取超高纯度氦气的方法及生产装置属于石油化工技术领域。本发明将膜分离、变压吸附、低温催化和脱硫脱碳技术集成在一起,对原料气中的氦进行提纯时,根据原料气的组成使原料气先后通过脱硫脱碳、膜分离、变压吸附、低温催化等多技术集群系统,得到体积分数不低于99.9999％的产品氦。该流程通过多技术间的相互协作,成功打破了单一分离技术的发展瓶颈,大大提高了产品氦的产率,降低了制氦过程的投资和能耗,提高了分离系统的使用寿命,拓宽了可利用的氦气资源。(A method for extracting ultra-high purity helium gas at normal temperature and a production device belong to the technical field of petrochemical industry. The invention integrates membrane separation, pressure swing adsorption, low temperature catalysis and desulfurization and decarburization technologies, when purifying helium in raw gas, the raw gas passes through a multi-technology cluster system of desulfurization and decarburization, membrane separation, pressure swing adsorption, low temperature catalysis and the like according to the composition of the raw gas, and the product helium with the volume fraction not less than 99.9999% is obtained. The process successfully breaks the development bottleneck of a single separation technology through mutual cooperation among multiple technologies, greatly improves the yield of the product helium, reduces the investment and energy consumption in the helium production process, prolongs the service life of a separation system, and widens the available helium resources.)

1. A method for extracting ultra-high purity helium gas at normal temperature is characterized in that: the method comprises the following steps of desulfurization and decarburization, gas membrane separation, pressure swing adsorption and low-temperature catalysis, wherein helium-containing feed gas is subjected to desulfurization and decarburization treatment and then enters a membrane separation process; enabling the helium-rich gas subjected to membrane separation to enter a primary low-temperature catalysis process to remove a hydrogen component in the helium-rich gas; the dehydrogenated helium-rich gas enters a secondary gas membrane separation process, and the treated helium-rich gas with higher helium concentration is sent to a primary pressure swing adsorption process; the obtained pure helium enters a secondary low-temperature catalysis process to remove trace hydrogen; the dehydrogenated helium enters a secondary pressure swing adsorption process; and sending qualified ultrapure helium gas out of the room after treatment.

2. The method of extracting ultra-high purity helium gas at ambient temperature as recited in claim 1, further comprising: the desorbed gas in the primary pressure swing adsorption process returns to the secondary gas membrane separation inlet; the desorbed gas in the secondary pressure swing adsorption process returns to the primary pressure swing adsorption process or a secondary gas membrane separation inlet; the secondary pressure swing adsorption adopts double-reflux pressure swing adsorption.

3. The method of extracting ultra-high purity helium gas at ambient temperature as recited in claim 1, further comprising: the volume content of carbon dioxide in the feed gas entering the primary or secondary membrane separation system is not higher than 20 percent, and preferably not higher than 0.4 percent; the volume content of hydrogen in the feed gas entering the secondary pressure swing adsorption system is not higher than 0.08ppm, preferably not higher than 0.01ppm, and the volume content of helium is not lower than 90%, preferably not lower than 99%, and most preferably not lower than 99.9%.

4. The method of extracting ultra-high purity helium gas at ambient temperature as recited in claim 1, further comprising: gas pressurization is carried out before the desulfurization and decarburization processes, and gas dehydration is carried out after the desulfurization and decarburization processes; gas pressurization is carried out before the low-temperature catalysis process, and gas dehydration is carried out after the low-temperature catalysis process; before the gas membrane separation process, gas pressurization, condensation, gas-liquid separation and heating are carried out; before the pressure swing adsorption process, gas pressurization, condensation and gas-liquid separation are carried out.

5. A production device for extracting ultra-high purity helium gas at normal temperature is characterized in that: the device comprises a desulfurization and decarburization system, a low-temperature catalysis system, a gas membrane separation system and a pressure swing adsorption system; wherein the purified gas outlet pipeline of desulfurization decarbonization system links to each other with membrane separation system's inlet pipeline once, membrane separation system's rich helium outlet pipeline links to each other with low temperature catalytic system's inlet pipeline once, catalytic system's dry dehydrogenation gas outlet pipeline links to each other with secondary membrane separation system's inlet pipeline, secondary membrane separation system's rich helium outlet pipeline links to each other with pressure swing adsorption system's inlet pipeline once, pressure swing adsorption system's helium outlet pipeline links to each other with secondary low temperature catalytic system's import, secondary low temperature catalytic system's dry dehydrogenation gas outlet pipeline links to each other with secondary pressure swing adsorption system's inlet pipeline.

6. A production device for extracting ultra-high purity helium gas at normal temperature is characterized in that: the desulfurization and decarburization system comprises a compressor, a cooler, a desulfurization and decarburization tower, a regeneration tower and a dehydration tower, wherein the compressor, the cooler, the desulfurization and decarburization tower and the dehydration tower are sequentially connected; the low-temperature catalytic system comprises a compressor, a cooler, a low-temperature catalytic tower and a drying tower, and the compressor, the cooler, the low-temperature catalytic tower and the drying tower are sequentially connected; the gas membrane separation system comprises a compressor, a condenser, a gas-liquid separator, a heater and a membrane component, and the compressor, the condenser, the gas-liquid separator, the heater and the membrane component are sequentially connected; the pressure swing adsorption system comprises a compressor, a condenser, a gas-liquid separator and a pressure swing adsorption tower group, and the sequentially connected equipment comprises the compressor, the condenser, the gas-liquid separator and the pressure swing adsorption tower group; the lean helium gas outlet pipeline of the gas membrane separation system is directly out of the boundary, the desorbed gas outlet pipeline of the primary pressure swing adsorption system is connected with the compressor inlet pipeline of the gas membrane separation system, and the desorbed gas outlet pipeline of the secondary pressure swing adsorption system is connected with the compressor inlet pipeline of the primary pressure swing adsorption system.

Technical Field

The invention belongs to the technical field of petrochemical industry. The invention integrates membrane separation, pressure swing adsorption, low temperature catalysis, desulfurization and decarburization technologies, and when purifying helium in the feed gas, the feed gas passes through a plurality of technology cluster systems of desulfurization and decarburization, membrane separation, pressure swing adsorption, low temperature catalysis and the like according to the composition of the feed gas to obtain qualified product helium. The invention can produce byproducts such as carbon dioxide, nitrogen and the like with higher purity according to the raw material condition besides helium and natural gas.

Background

So far, helium gas is mainly from natural gas containing helium, so that natural gas helium extraction technology becomes a main research direction in the field of helium extraction.

The related patents related to helium recovery or helium production looked up at present mainly comprise two types, one type is process tail gas purification and separation; the other is helium extracted from natural gas or air separation tail gas, in the patents, most of the helium is cryogenic cooling or combination of cryogenic cooling and other technologies, the method can obtain a helium product with high purity, but the production energy consumption is high, and the economical efficiency of the method can not meet the requirement when the method is operated under the working condition of not by-producing LNG; some pure membrane methods or pressure-swing/temperature-swing adsorption technologies can obtain helium products with certain purity, but the application range is narrow, the helium products with high purity cannot be obtained, and the helium product yield is not high; the method is characterized in that a small part of the method adopts catalysis, membrane separation, pressure swing adsorption and temperature swing adsorption technologies, but related patents adopt common pressure swing adsorption technologies in an adsorption link, the purity of the obtained helium gas does not meet the requirement of ultra-pure helium, only one-time dehydrogenation is carried out in a dehydrogenation link, the requirement of the ultra-pure helium on the content of hydrogen not exceeding 0.1ppm is difficult to achieve, and corresponding measures are not taken on the influence caused by the increase of heat in the dehydrogenation link.

Disclosure of Invention

Aiming at the situations, the invention adopts a secondary low-temperature catalysis technology to ensure the hydrogen removal effect, and adopts constant-temperature dehydrogenation to eliminate the influence of the exothermic reaction in the dehydrogenation link; the invention also innovatively introduces a double-reflux pressure swing adsorption technology, and obviously reduces equipment investment and operation consumption under the condition of fully ensuring that the purity of helium can reach the ultra-pure helium. Compared with the currently granted or published patents at home and abroad, the method has obvious innovation.

The double-reflux pressure swing adsorption technology is characterized in that three adsorption towers which are connected in parallel in a form are utilized to form a separation unit, the top and the bottom of the separation unit are respectively provided with a buffer tank, a compressor is connected between the bottom buffer tank and the bottoms of the three adsorption towers, the feeding position is arranged at the bottom of the adsorption towers, gas which is difficult to adsorb is discharged to a light component buffer tank at the top of the separation unit, and the reflux operation of light component streams in the three adsorption towers is realized through control valves on connecting pipelines; the impurity gas is discharged to a 'heavy component' buffer tank at the bottom of the separation unit, and the reflux operation of 'heavy component' flow in the three adsorption towers is realized through a compressor connected with the impurity gas and a control valve on a connecting pipeline. The gas is refluxed for many times between the top and the bottom of the adsorption tower which are connected in parallel in the form, so that the high-precision separation of light and heavy components in the raw material gas is realized.

The low-temperature catalytic technology is a technology which can still normally react when the temperature of oxidative dehydrogenation reaction is reduced to be lower than the reaction temperature of the oxidative dehydrogenation reaction in the absence of a catalyst by using palladium catalyst. In order to ensure the safety of the reaction device, a heat transfer device is additionally arranged in the reactor, and the heat transfer device additionally arranged in the reactor is used for transferring reaction heat out in time during reaction, so that the temperature of the system is always kept at a constant temperature.

A method for extracting ultra-high purity helium gas at normal temperature is a multi-technology cluster method, the cluster technology comprises desulfurization and decarburization, gas membrane separation, pressure swing adsorption and low-temperature catalysis technologies, and helium-containing feed gas enters a membrane separation process after being subjected to desulfurization and decarburization; enabling the helium-rich gas subjected to membrane separation to enter a primary low-temperature catalysis process to remove a hydrogen component in the helium-rich gas; the dehydrogenated helium-rich gas enters a secondary gas membrane separation process, and the treated helium-rich gas with higher helium concentration is sent to a primary pressure swing adsorption process; the obtained pure helium enters a secondary low-temperature catalysis process to remove trace hydrogen; the dehydrogenated helium enters a secondary pressure swing adsorption process; and sending qualified ultrapure helium gas out of the room after treatment.

The helium-poor tail gas of the secondary membrane separation returns to the inlet of the primary membrane separation process, the desorbed gas of the primary pressure swing adsorption process returns to the inlet of the secondary gas membrane separation process, the desorbed gas of the secondary pressure swing adsorption process returns to the primary pressure swing adsorption process or the inlet of the secondary gas membrane separation process, and the secondary pressure swing adsorption adopts double-reflux pressure swing adsorption.

The volume content of carbon dioxide in the feed gas entering the primary or secondary membrane separation system is not higher than 20 percent, and preferably not higher than 0.4 percent; the volume content of hydrogen in the feed gas entering the secondary pressure swing adsorption system is not higher than 0.08ppm, preferably not higher than 0.01ppm, and the volume content of helium is not lower than 90%, preferably not lower than 99%, and most preferably not lower than 99.9%.

Gas pressurization is carried out before the desulfurization and decarburization processes, and gas dehydration is carried out after the desulfurization and decarburization processes; gas pressurization is carried out before the low-temperature catalysis process, and gas dehydration is carried out after the low-temperature catalysis process; gas pressurization and pretreatment are carried out before the gas membrane separation process; gas pressurization and pretreatment are carried out before the pressure swing adsorption process.

In order to achieve the aim, the invention provides a production device for extracting the ultra-high purity helium at normal temperature, which comprises a desulfurization and decarburization system, a low-temperature catalysis system, a gas membrane separation system and a pressure swing adsorption system; wherein the purified gas outlet pipeline of desulfurization decarbonization system links to each other with membrane separation system's inlet pipeline once, membrane separation system's rich helium outlet pipeline links to each other with low temperature catalytic system's inlet pipeline once, catalytic system's dry dehydrogenation gas outlet pipeline links to each other with secondary membrane separation system's inlet pipeline, secondary membrane separation system's rich helium outlet pipeline links to each other with pressure swing adsorption system's inlet pipeline once, pressure swing adsorption system's helium outlet pipeline links to each other with secondary low temperature catalytic system's import, secondary low temperature catalytic system's dry dehydrogenation gas outlet pipeline links to each other with secondary pressure swing adsorption system's inlet pipeline. The raw material gas firstly enters a desulfurization and decarburization system;

the desulfurization and decarburization system comprises a compressor, a cooler, a desulfurization and decarburization tower, a regeneration tower and a dehydration tower, wherein the compressor, the cooler, the desulfurization and decarburization tower and the dehydration tower are sequentially connected; the low-temperature catalytic system comprises a compressor, a cooler, a low-temperature catalytic tower and a drying tower, and the compressor, the cooler, the low-temperature catalytic tower and the drying tower are sequentially connected; the gas membrane separation system comprises a compressor, a condenser, a gas-liquid separator, a heater and a membrane component, and the compressor, the condenser, the gas-liquid separator, the heater and the membrane component are sequentially connected; the pressure swing adsorption system comprises a compressor, a condenser, a gas-liquid separator and a pressure swing adsorption tower group, and the sequentially connected equipment comprises the compressor, the condenser, the gas-liquid separator and the pressure swing adsorption tower group; the lean helium gas outlet pipeline of the gas membrane separation system is directly out of the boundary, the desorbed gas outlet pipeline of the primary pressure swing adsorption system is connected with the compressor inlet pipeline of the gas membrane separation system, and the desorbed gas outlet pipeline of the secondary pressure swing adsorption system is connected with the compressor inlet pipeline of the primary pressure swing adsorption system.

Drawings

The invention is further described with reference to the following figures and detailed description.

FIG. 1 is a flow chart of the present invention, and is a schematic process flow chart of example 1. FIG. 2 is a schematic flow diagram of the process of the present invention for treating non-hydrogen containing natural gas to extract helium and is also a schematic flow diagram of the process of example 2. FIG. 3 is a schematic flow diagram of the process of the present invention for extracting helium from non-sour carbon-containing natural gas, along with a schematic flow diagram of the process of example 3.

Detailed Description

Example one

For an understanding of the present embodiment, refer to FIG. 1. The figure shows the main devices and their mutual connection relation of the present invention.

And the helium-containing feed gas I enters a primary membrane separation system after being subjected to desulfurization and decarburization treatment. The membrane module operating pressure was 2.90MPag, the operating temperature was 60 ℃. After the treatment of the gas separation membrane, the helium-removed tail gas is sent out, and the concentrated hydrogen-containing raw gas is sent into a primary low-temperature catalytic system. And (4) feeding the dehydrogenation feed gas subjected to dehydrogenation treatment by the primary low-temperature catalytic system into a secondary membrane separation system. The membrane module operating pressure was 2.90MPag, the operating temperature was 60 ℃. After the gas separation membrane treatment, the helium-removed tail gas returns to the inlet of the primary membrane separation system, the feed gas with high helium content is sent into the primary pressure swing adsorption system, the operating pressure of the pressure swing adsorption tower is 2.9MPag, and the operating temperature is 30 ℃. After the first pressure swing adsorption treatment, the desorbed gas of the first pressure swing adsorption system returns to the inlet of the secondary membrane separation system, the concentration of the extracted helium reaches 99.9 percent, and the extracted helium is sent to a secondary low-temperature catalytic system for continuous dehydrogenation. The dehydrogenated helium enters a secondary pressure swing adsorption system, the operating pressure of the secondary pressure swing adsorption system is 1.0MPag, and the operating temperature is 30 ℃. The helium concentration of the product after the secondary purification reaches more than 99.9999 mol%, the product is sent out, and the desorbed gas returns to the inlet of the primary pressure swing adsorption system.

The specific process flow parameters for this example are shown in Table 1.

TABLE 1 data sheet for hydrogen and carbon containing natural gas helium purification and recovery

In this example, the total helium recovery for the cluster technique was 92.7%.

Example two

For an understanding of the present embodiment, reference is made to FIG. 2. The figure shows the main devices and their mutual connection relation of the present invention.

And feeding the helium-containing feed gas II into a membrane separation system. The membrane module operating pressure was 6.90MPag, the operating temperature was 70 ℃. After the treatment of the gas separation membrane, the helium-removed tail gas is sent out, the feed gas with high helium content is sent into a primary pressure swing adsorption system, the operating pressure of a pressure swing adsorption tower is 2.9MPag, and the operating temperature is 30 ℃. After the primary pressure swing adsorption treatment, desorbed gas of the primary pressure swing adsorption system returns to the inlet of the membrane separation system, the concentration of the extracted helium reaches 99.9 percent, and the desorbed helium enters a secondary pressure swing adsorption system, wherein the operating pressure of the secondary pressure swing adsorption system is 0.9MPag, and the operating temperature is 30 ℃. The secondary purified helium product with concentration over 99.9999 mol% is sent out and the desorbed gas is returned to the inlet of the primary pressure swing adsorption system.

The specific parameters of this example are shown in Table 2.

TABLE 2 helium-containing natural gas helium purification recovery data sheet

In this example, the total helium recovery for the cluster technique was 96.88%.

EXAMPLE III

For an understanding of the present embodiment, refer to FIG. 3. The figure shows the main devices and their mutual connection relation of the present invention.

And feeding the helium-containing feed gas III into a primary membrane separation system. The membrane module operating pressure was 2.90MPag, the operating temperature was 70 ℃. After the treatment of the gas separation membrane, the helium-removed tail gas is sent out, and the concentrated hydrogen-containing raw gas is sent into a primary low-temperature catalytic system. And (4) feeding the dehydrogenation feed gas subjected to dehydrogenation treatment by the primary low-temperature catalytic system into a secondary membrane separation system. The membrane module operating pressure was 2.90MPag, the operating temperature was 70 ℃. After the gas separation membrane treatment, the helium-removed tail gas returns to the inlet of the primary membrane separation system, and the feed gas with high helium content is sent to the secondary low-temperature catalytic system for continuous dehydrogenation. The dehydrogenated helium enters a pressure swing adsorption system, the operating pressure of the pressure swing adsorption system is 1.9MPag, and the operating temperature is 30 ℃. The purified product helium with the concentration of more than 99.9999mol percent is sent out, and the desorbed gas returns to the inlet of the secondary membrane separation system.

The specific parameters of this example are shown in Table 2.

TABLE 2 helium-containing natural gas helium purification recovery data sheet

In this example, the total helium recovery for the cluster technique was 97.38%.