JPS62167204A - Method and device for continuously purifying high-purity gaseous hydrogen - Google Patents

Abstract

PURPOSE:To continuously recover high-purity gaseous hydrogen in high yield from crude gaseous hydrogen by providing >=3 purification vessels, and furnishing >=2 separators for continuously recovering crude gaseous hydrogen from impurities when high-purity hydrogen is produced from crude gaseous hydrogen. CONSTITUTION:Gaseous impurities are removed from crude gaseous hydrogen having about 99.999% purity to obtain gaseous hydrogen having 99.9999% purity. In this case, hydrogen purifying vessels A, B, and C packed with a hydrogen occluding alloy are provided, and two separation vessels (a) and (b) for separating gaseous hydrogen having about the same purity as the crude gaseous hydrogen from the impurities coming out from the separation vessels are furnished. The raw crude gaseous hydrogen is introduced into the purification vessels A-C, the hydrogen is occluded in the hydrogen occluding alloy, the impurities are discharged and introduced into the separation vessels (a) and (b) to separate crude gaseous hydrogen from the impurities, and the crude gaseous hydrogen is returned to the hydrogen purifying vessels A-C. The occlusion of gaseous hydrogen from the crude gaseous hydrogen, the discharge of impurities, and the discharge of purified gaseous hydrogen are performed while providing a time phase difference, and high-purity gaseous hydrogen is continuously recovered in high yield from the crude gaseous hydrogen.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method and apparatus for continuous purification of high-purity hydrogen gas with a high recovery rate.

[Conventional technology]

As shown in Fig. 4, a conventional high-purity hydrogen gas purification method using a hydrogen storage alloy involves introducing crude hydrogen gas (99,999% Hz) into a hydrogen storage alloy container 1 from a t cylinder or line through a pulp 2. Then, only hydrogen gas is stored in the hydrogen storage alloy (A).

At this time, only impurities are concentrated in the space inside the container 1. In order to remove this impurity, when the pulp 3 is opened and closed,
The pressure inside the container 1 (space) decreases due to the release of impurities. As a result of this reduced pressure, hydrogen gas is released from the alloy up to the hydrogen gas equilibrium pressure with the hydrogen storage alloy, so that the content of impurities in the space of the container 1 is reduced. The hydrogen gas purity in the container is successively increased by the effect of such pulp opening/closing operations, and hydrogen gas having a purity of 99.9999% or more is obtained through the pulp 4t.

[Problem that the invention seeks to solve]

When hydrogen gas is purified using a hydrogen storage alloy, one cycle includes (1) selective storage of only hydrogen from crude hydrogen gas, (2) pulp opening/closing operation for releasing impurities, and (
Three steps are required: 3) release (supply) of purified hydrogen gas.

For this reason, it has been difficult to continuously supply purified hydrogen gas to a system that requires the hydrogen gas using two or fewer conventional purification vessels.

Furthermore, the recovery rate of hydrogen gas in the crude gas is low when using only a purification vessel, and no measures have been taken to continuously recover hydrogen gas from impurities containing a small amount of hydrogen gas.

The present invention proposes a method and apparatus for obtaining purified hydrogen gas continuously and with a high recovery rate.

[Means for solving problems]

In the present invention, the above problems are solved by installing three or more purification vessels and two or more separation vessels to continuously recover hydrogen gas at the purity level of crude hydrogen gas from impurities. It is something to do.

That is, the present invention provides the following features: (1) introduction of crude hydrogen gas into a purification vessel containing a hydrogen storage alloy, (2) release of impurity gas containing hydrogen gas, and (6) removal of purified hydrogen gas from the system. The process consisting of discharging into the equipment is carried out at a predetermined time difference among the plurality of refining vessels, and at the same time, the discharging into the separation vessel containing the hydrogen storage alloy is
4) A process consisting of introducing impurity gas from the purification container, (5) discharging the impurity gas, and (6) refluxing the separated gas to the crude hydrogen gas system is performed at a predetermined time difference among the plurality of separation containers. A continuous purification method for high-purity hydrogen gas characterized by: (2) a purification container group consisting of a plurality of containers containing a hydrogen storage alloy; and a separation container group consisting of a plurality of containers containing a hydrogen storage alloy. , a continuous purification device for high-purity hydrogen gas, characterized in that it is comprised of a control device that controls the pulp between the containers, between the container groups, and between an external device and the container groups.

[Effect]

In the present invention, purified hydrogen gas can be obtained continuously by arranging three or more containers in consideration of the time required for three steps for hydrogen gas purification and providing a phase difference in the operation of each container. .

In addition, in the present invention, in order to increase the hydrogen gas recovery rate from crude hydrogen gas, two or more separation vessels are arranged to recover hydrogen gas at the level of crude hydrogen gas from impurities, and separation is performed in accordance with the operation process of the purification vessel. A sequence is set so that operations can be performed, and separation operations can be performed continuously.

The separation operation is basically the same as the purification operation and consists of six steps, but the number of times the pulp is opened and closed to release impurities can be reduced at the crude hydrogen gas purity level.

〔Example〕

FIG. 1 is a diagram for explaining one embodiment of the present invention.
(a) is a diagram of the arrangement and piping of the purification/separation vessels, and (b) is a system diagram of each operation of the individual vessels.

In Fig. 1(a), both the purification and separation vessels are LaN1
Filled with 32.5'Kg, purification containers (A), (B),
(The impurities of carbon are led together to the separation vessels (a) and (b), the impurities in the separation vessels (a) and (b) are sent to the atmosphere, and the separated gas, which has been improved to the purity of crude hydrogen gas, is sent to the purification vessel ( A)
.

(B), (is led to the crude hydrogen gas inlet.

FIG. 1(b) shows an example in which the refining vessels (A), (B), and (0) were operated by changing their phase differences. In FIG. 1(b), α indicates storage of crude hydrogen gas, β indicates release of impurities, and γ indicates release of purified gas or separated gas. In this way, when the purification container (A) is storing crude hydrogen gas α and releasing impurities β, that is, when the purification container (A) cannot supply purified hydrogen gas, the other container (B
), purified hydrogen gas can be supplied from (0). In addition, the impurity gas released from the N container is separated into separation containers (a) and (b).
Although it depends on the alloy capacity of
), one cycle of four purification vessels is
I decided to lead it to the original separation container.

As a result of the above, the conventional hydrogen gas recovery rate was 75% (999 CHH).
2→99.9999chi H2) was able to be increased to 95%. Furthermore, as is clear from the M1 diagram (b), it has become possible to supply both purification and separation continuously.

The operating conditions for the three steps at this time are as follows.

1. Step... (Hydrogen gas storage); Crude hydrogen gas supply pressure 8 Y/ciG Container cooling water temperature L 330°C 2. Step... (Impurity release); Release pressure 7 klF/cm "G Container heating water temperature 280℃ Pulp opening/closing number 240 times 6. Step... (purified hydrogen gas release); Release pressure -
= 4 kli'/cm2G Container heating water temperature 80℃ (Separation container) 1. Step... (Hydrogen gas absorption in impurities); Supply pressure 7 kli'/cm2G Container cooling water temperature Z30℃ 2 steps...・(Release of impurities); Release pressure = 7 to 97cm"G Container heating water temperature 80℃ 10 times 5 steps per pulp opening/closing count... (Rough hydrogen gas release); Release pressure 8yu/(z"G Container Heated water temperature: 380°C. Figure 2 shows how purified hydrogen gas is continuously supplied at this time. Figure 2 is calculated assuming the capacity of each container is 400 tons. For reference, the conventional method is used. are also shown.

Furthermore, Table 1 shows the gas balance at this time.

The recovery rate of purified hydrogen gas in the above case is as follows.

In the above embodiment, the valve operations shown in Table 2 are performed using a sequencer.
Automatically controlled by etc. In Table 2, 1 to 20 in the pulp operation column correspond to valves 1 to 20 shown in Figure 3 (,), and 'ro' T I G in the time column is shown in Figure 3 (b). Corresponds to To-Tlo. In addition, Fig. 3(a), (
1)) is the same as FIGS. 1(a) and (b).

〔Effect of the invention〕

According to the present invention, the above-mentioned system, (1) Continuous supply of hydrogen gas (2) Improving hydrogen gas recovery rate (3) Automation of hydrogen gas purification process can be achieved.

[Brief explanation of drawings]

Figures 1 (a) and (b) are diagrams for explaining an example of the method and apparatus of the present invention, Figure 2 is a diagram showing a continuous supply mode of purified hydrogen gas in an example, and Figure 3 (a). ) and (b) are the same as FIGS. 1(a) and (b), and are diagrams for explaining the mode of valve operation in the embodiment, and FIG. 4 is a diagram showing the prior art. Sub-agents 1) Meifuku agent Ryo Hagiwara - Enoki agent Atsuo Anzai

Claims (2)

[Claims] (1) Introducing crude hydrogen gas into a purification vessel containing a hydrogen storage alloy, (2) releasing impurity gas containing hydrogen gas, and (3) releasing purified hydrogen gas to equipment outside the system. The above steps are carried out at a predetermined time difference among the plurality of refining vessels, and at the same time, (
4) A process consisting of introducing impurity gas from the purification container, (5) discharging the impurity gas, and (6) refluxing the separated gas to the crude hydrogen gas system is performed at a predetermined time difference among the plurality of separation containers. A continuous purification method for high-purity hydrogen gas characterized by the following. (2) A refining container group consisting of a plurality of containers containing a hydrogen storage alloy, a separation container group consisting of a plurality of containers containing a hydrogen storage alloy, and between the containers and container groups, and between external devices and the container group. 1. A continuous purification device for high-purity hydrogen gas, characterized in that it is comprised of a control device for controlling pulp in between.