DE102016221779A1 - Method for filling a pressure vessel - Google Patents

Abstract

The invention relates to a method for filling a pressure vessel with gas, comprising the following steps in a given order: providing a pressure vessel with a bubble arranged in the pressure vessel, wherein the bubble is filled with a starting gas, in particular air, and filling the gas into the pressure vessel, wherein the gas is filled between the inner wall of the pressure vessel and the bladder.

Description

The technology disclosed herein relates to a pressure vessel and a method for filling a pressure vessel with gas. The gas is in particular a fuel gas. The pressure vessel is preferably used in a vehicle.

Pressure vessels considered here are used, for example, in vehicles for storing fuel gas. The fuel gas is, for example, hydrogen or natural gas. The fuel gas is stored in the gaseous state of aggregation in the pressure vessel. The pressure vessels must be filled after manufacture and before commissioning or after emptying at a service with the fuel gas. The pressure vessel is filled after its production with air at ambient pressure. For reasons of explosion protection, it is not possible to perform a filling with the fuel gas directly. In this case, an ignitable mixture could arise from the fuel gas and atmospheric oxygen.

Therefore, in the prior art, the fuel gas is not directly filled in the air-filled pressure vessel, but it is initially an intermediate filling with an inert gas. The resulting mixtures of air and inert gas or inert gas and fuel gas are each harmless from the point of view of explosion protection. Especially with pressure vessels with only one opening, the air can not be easily replaced by the inert gas or the inert gas against the fuel gas. Instead, pressure change rinses generally take place: the gas to be filled in (inert gas or fuel gas) is introduced into the pressure vessel. It creates an overpressure against the environment while maintaining the pressure limit of the pressure vessel. Subsequently, the overpressure is released again approximately to a possibly necessary minimum container pressure and the procedure is repeated until the gas to be filled with the required purity is present in the pressure container. A minimum container pressure may be required, for example, to avoid detachment of a (plastic) liner wall from the surrounding fiber reinforcement.

Furthermore, especially if the pressure vessel does not require a minimum pressure of the vessel due to the design, an evacuation of the pressure vessel is also possible, so that the gas originally contained therein is almost completely removed before the gas to be filled is filled into the pressure vessel. Both the pressure swing flushing and the evacuation is relatively expensive in terms of time and the required equipment. Furthermore, in the pressure swing rinse gas mixtures, which must be disposed of accordingly.

It is a preferred object of the technology disclosed herein to reduce or eliminate at least one disadvantage of a previously known solution or to suggest an alternative solution. In particular, it is an object of the technology disclosed herein to provide a fast, safe and efficient method for filling a pressure vessel and a corresponding pressure vessel. Other preferred objects may result from the beneficial effects of the technology disclosed herein. The object (s) is / are solved by the subject matter of claim 1. The dependent claims are preferred embodiments.

The object is achieved by a method for filling a pressure vessel with gas. The pressure vessel is used in particular in a vehicle. The pressure vessel may already be in the vehicle during filling. The method comprises at least the following steps in the given order:

First, a pressure vessel is provided. In the pressure vessel is a bubble. The bladder is in particular made of a flexible material. The bubble is filled with a source gas. The starting gas is in particular air. In particularly critical cases, due to the explosion safety, an inert gas can also be used as the starting gas. The air originally in the interior of the pressure vessel in the bubble can be exchanged for example by a conventional method against the inert gas.

The pressure vessel may include a liner. The liner forms the hollow body in which the gas is stored. The liner may for example be made of aluminum or steel or of their alloys. Further preferably, the liner may be made of a plastic. It can also be used a linerless pressure vessel.

In particular, it is provided that the interior of the pressure vessel is completely filled by the bubble filled with the starting gas.

In the next step, the filling of the gas, in particular fuel gas, takes place in the pressure vessel. It is envisaged that the gas is filled between the inner wall of the pressure vessel and the bladder. The introduced gas is thus initially limited by the inner wall of the pressure vessel and the decreasing bubble. The inflowing gas reduces the size of the bubble and displaces the starting gas. An opening of the bladder is arranged at an opening of the pressure vessel, so that the displaced starting gas flows out of the bladder and thus also out of the pressure vessel. At the Filling of the gas, the volume of the starting gas formed by the bubble is steadily smaller until the bubble is completely empty and the complete volume of the pressure vessel is occupied by the gas to be filled.

The method presented here ensures that the starting gas originally contained in the pressure vessel is always separated from the gas to be filled. A use of inert gas is therefore not absolutely necessary.

The process can be carried out very quickly, since no repeated passages as in the pressure swing flushing are necessary.

Preferably, it is provided that the bubble rests at least partially against the inner wall of the pressure vessel before filling the gas. Particularly preferably, it is provided that before the filling of the gas, the bladder rests completely on the inner wall of the pressure vessel.

Furthermore, it is preferably provided that there are no air-filled cavities between the bubble and the inner wall before the gas is introduced.

In particular, it is provided that the bubble adheres to the inner wall before filling the gas. Preferably, the bubble adheres cohesively to the inner wall. This adhesion of the bubbles to the inner wall is achieved, in particular, by producing the pressure vessel from a plurality of layers, the layers adhering to one another. The innermost layer represents the bubble. By filling the gas between the bubble and the inner wall, the bubble is peeled off the inner wall. The "adhesion" is preferably so strong as to ensure a secure abutment of the bladder on the inner wall and on the other hand so weak as to allow peeling. Depending on the embodiment, a release agent and / or an adhesion promoter between the bladder and the inner wall may be useful in order to design this "adhesion" accordingly and / or a surface-active substance to in the formation or production of the bladder, preferably from the liquid phase To achieve a sufficiently good wetting of the inner wall by the bubble forming medium.

In a particularly preferred embodiment, it is provided that the bladder is manufactured together with the inner wall of the pressure vessel. The bladder, like the liner itself, can be made by rotational molding, blow molding or injection molding. It is preferably ensured in the production by use of a release agent that the bubble later easily dissolves again from the inner wall of the container.

Alternatively, it is preferably provided that the bladder is inserted into the pressure vessel after the production of the inner wall. For this purpose, it is preferably provided that a liquid hardenable material, in particular rubber or plastic, is poured into the pressure vessel. Particularly preferably, the pressure vessel is pivoted about several axes during the curing of this material, so that the material rests against the inner wall. After curing, this material represents the bubble.

Further, it is preferably provided that the bladder, such as an empty balloon, is inserted into the pressure vessel and is inflated in the pressure vessel until the entire volume of the pressure vessel is occupied by the bladder. The bubble is preferably inflated with air or inert gas.

Preferably, the bubble is removed after filling the gas, in particular after complete filling of the pressure vessel with the gas from the pressure vessel.

As described above, can be dispensed with the use of an inert gas as a rule. For particularly critical cases, however, it is also preferable to use a further bladder in the pressure vessel and in the first bladder already described. In this case, before the filling of the gas, in particular the fuel gas, an additional gas, preferably an inert gas, is introduced between the two bubbles. Once the additional gas and thus the outer bladder occupies the entire volume of the pressure vessel, the gas to be filled can be filled between the outer bladder and the inner wall of the pressure vessel.

The gas that is introduced into the pressure vessel is, in particular, a fuel gas. The fuel gas is in particular hydrogen or a carbon-containing fuel gas. The carbonaceous fuel gas is especially natural gas.

The method presented here is used in particular in a pressure vessel with only one opening.

In a preferred variant, the method described here is carried out on a pressure vessel which is installed in a vehicle.

The technology disclosed herein further includes the pressure vessel. The pressure vessel is preferably designed for carrying out the described method. In the pressure vessel at least one bubble is arranged. The bladder is open at an opening of the pressure vessel to the outside. Between the inner wall of the pressure vessel and the bubble, the gas, in particular fuel gas can be filled.

The subclaims and advantageous embodiments described in the context of the disclosed method also find correspondingly advantageous application to the pressure vessel. In particular, it is preferably provided that the bubble rests at least partially against the inner wall of the pressure vessel before filling the gas. Particularly preferably, it is provided that before the filling of the gas, the bladder rests completely on the inner wall of the pressure vessel. Furthermore, it is preferably provided that there are no air-filled cavities between the bubble and the inner wall before the gas is introduced. In particular, it is provided that the bubble adheres to the inner wall before filling the gas. Preferably, the bubble adheres cohesively to the inner wall. By filling the gas between the bladder and the inner wall, the bladder is peeled off the inner wall.

• 1 bis 3 schematische Ansichten eines Druckbehälters zur Erläuterung des offenbarten Verfahrens.

The technology disclosed herein will now be explained with reference to the figures. Show it:

• 1 to 3 schematic views of a pressure vessel for explaining the disclosed method.

The 1 to 3 show schematically simplified the flow of the method for filling a pressure vessel 1 with a gas 6 , The pressure vessel 1 is used in particular in a vehicle for storing a fuel gas.

As 1 shows, the pressure vessel points 1 an opening 2 on. In the pressure vessel 1 there is a bubble 8th , The bubble 8th is to the opening 2 open. The bubble 8th lies on the inner wall of the pressure vessel 1 completely on.

Further clarified 1 that the bubble 8th with a source gas 3 , in particular air, is filled while keeping the whole volume of the pressure vessel 1 occupies.

2 shows the pressure vessel 1 during filling with the gas 6 , The gas 6 will be over the opening 2 between the inner wall of the pressure vessel 1 and the bubble 8th initiated. This reduces the bubble 8th and the starting gas 3 from the bubble 8th flows over the opening 2 outward.

The inner wall of the pressure vessel 1 is here preferably together with the bladder 8th made, so the bubble 8th in the initial state on the inner wall of the pressure vessel 1 liable. As 2 shows, the bubble dissolves 8th when the gas flows 6 from the inner wall.

3 shows a condition where the bubble 8th is completely emptied. The entire volume of the pressure vessel 2 gets off the gas 6 ingested. The empty bubble 8th can be taken in a following steps.

The foregoing description of the present invention is for illustrative purposes only, and not for the purpose of limiting the invention. Various changes and modifications are possible within the scope of the invention without departing from the scope of the invention and its equivalents.

LIST OF REFERENCE NUMBERS

1

pressure vessel

2

opening

3

air

6

Gas, especially fuel gas

8th

bladder

Claims (10)

Method for filling a pressure vessel (1) with gas (6), comprising the following steps in a given order: Providing a pressure vessel (1) with a bladder (8) arranged in the pressure vessel (1), the bladder (8) being filled with a starting gas (3), in particular air, and • filling the gas (6) in the pressure vessel (1), wherein the gas (6) between the inner wall of the pressure vessel (1) and the bladder (8) is filled. Method according to Claim 1 , wherein the bladder (8) before filling of the gas (6) at least partially, preferably completely, abuts the inner wall of the pressure vessel (1). Method according to one of the preceding claims, wherein the bladder (8) adheres to the inner wall before filling the gas (6) and is peeled off by the filling of the gas (6). Method according to one of the preceding claims, wherein the bladder (8) is manufactured together with the inner wall of the pressure vessel (1). Method according to one of Claims 1 to 3 , wherein the bladder (8) after the manufacture of the inner wall in the pressure vessel (1) is used. Method according to one of the preceding claims, wherein the bladder (8) after the filling of the gas (6) from the pressure vessel (1) is removed. Method according to one of the preceding claims comprising a further bladder (8), wherein before the filling of the gas (6) between the two Bubbles an additional gas, preferably inert gas, is filled. Method according to one of the preceding claims, wherein the gas (6) is a fuel gas, preferably hydrogen or carbon-containing fuel gas. Method according to one of the preceding claims, wherein the pressure vessel (1) is located in a vehicle during the implementation of the method. Pressure vessel (1), preferably for carrying out the method according to one of the preceding claims, wherein a bubble (8) is arranged in the pressure vessel (1), wherein the bubble (8) at an opening (2) of the pressure vessel (1) to the outside is, and wherein between the inner wall of the pressure vessel (1) and the bladder (8), a gas (6) can be filled.

Images