JP4992828B2 - Low acid concentration adsorption system for storage cases - Google Patents

Description

This invention was developed to remove oxygen in a low oxygen concentration case that prevents mold and pests previously invented in a short period of time, and in particular, improved the bellows to prevent abnormal expansion of gas due to atmospheric pressure and temperature, etc. This is a system equipped with a safety valve.

In order to preserve the exhibits in an environmentally friendly manner, oxygen in the case was removed using an oxygen adsorbent, but the oxygen concentration was 0 for the growth in the mold and death of pests relative to the volume in the case. 1% or less, depending on the temperature difference, it takes a considerable amount of time due to room temperature convection, and there are also devices in which nitrogen gas is poured into the case using a nitrogen gas generator. This method has a problem that nitrogen gas must always be discharged out of the case.

In cases where conventional oxygen adsorbents are used, it is difficult to determine whether the adsorbent in the adsorbent has sustained the effect of the oxygen adsorbent when used for many years. When replacing the adsorbent, it can be replaced without removing the case lid. There wasn't.

Problems that the invention can solve

  As described above, using an oxygen adsorbent, it takes a considerable amount of time to reach a low oxygen concentration of 0.1%, and injecting nitrogen gas from a conventional nitrogen gas generator is always outside. There was a problem that had to be continued.

  The bellows used in previous cases has been improved to withstand abnormal pressure changes due to temperature, atmospheric pressure, adsorbent, and other factors, which have a small tolerance for gas pressure and are somewhat unsafe for safety. I had to.

Since the conventional oxygen adsorbent of the low oxygen concentration display case is stored in the case, it is troublesome and difficult, so the oxygen adsorbent must be replaced without opening the case.

Means to solve the problem

The expansion rate of gas is usually said to be 1%, but in the course of repeated experiments, multiple causes such as atmospheric pressure and temperature overlap, and there is a fact that experimental results far exceeded 1%. Improvements were made to absorb about 2% expansion of the gas to volume.

Although the decrease in oxygen concentration in previous cases depends on the influence of room temperature, it took 24 hours or more in a room temperature room with an experimental case volume of 4500 ml, but nitrogen gas was supplied from one side using two pipes. When the oxygen concentration is 0 or 2%, the discharge valve is closed and circulated with a small air pump when the oxygen concentration is 0 or 2%. The oxygen adsorbent stored in the case can be absorbed.

Equipment such as oxygen adsorption tanks, humidity control tanks, pumps, safety valves, etc., were put together in a small storage room to facilitate the management and maintenance of the gas in the case.

The invention's effect

The newly developed low oxygen concentration adsorption system circulates the nitrogen gas once injected without flowing outside, and oxygen leaking from the outside is slowly absorbed by the oxygen adsorbent, and the adsorbent carbon dioxide gas is stored by what is stored. It is easy to select and replace the adsorbent to be generated or the adsorbent that does not emit carbon dioxide, and two types can be selected in one case.

With this invention, in any sealed case, it is possible to make a low oxygen concentration display case by connecting an oxygen absorbing system with capacity suitable for the volume to the bottom and side with a pipe. It is.

In conventional low oxygen concentration display cases, oxygen adsorbents are stored together in the case, so it took too much time to replace the oxygen adsorbents as needed. The agent can be exchanged, and it can be offered at a lower price than the conventional nitrogen gas generator, and the maintenance cost can be reduced.

Embodiment 1
FIG. 1 is a configuration diagram in the case where an oxygen removal / humidity control system 2 according to Embodiment 1 of the present invention is applied to an exhibition storage device 1 composed of a transparent display case (for example, a volume of 87.8 liters) and its pedestal. Show. A thick line connecting each element is a pipe for a gas flow path. In order to reduce the oxygen in the exhibition storage device 1 as quickly as possible, the manual valves 3, 4, 5, 7, and 8 are first opened (6 is closed), and the manual valve 3, the flow meter (from the nitrogen gas cylinder 10) is opened. FM) 11, nitrogen gas is press-fitted into the exhibition storage device 1 via the manual valve 4. Since the manual valves 5 and 7 are open, the air in the case is discharged from the gas discharge pipe 20 through these valves. The oxygen concentration in the exhibition storage device 1 is measured by the oxygen concentration meter (OM) 12 through the oxygen concentration measurement pipes 22 and 23, and nitrogen gas is introduced until the oxygen concentration is reduced to about 2.0%. . In order to reach the concentration, for example, the press-in flow rate is 3.0 l / min. In this case, it takes about 1 hour.

When the oxygen concentration is 2.0% or less, the gas in the exhibition storage device 1 is circulated through a closed circuit composed of the oxygen adsorption device (AB) 14 and the humidity control device 13 to perform oxygen removal and humidity control operations. After the manual valves 3 and 7 are closed and the manual valves 4, 5, 6 and 8 are opened, the air pump (AP) 15 is driven, and the manual valve 5, the air pump 15, the oxygen adsorber (AB) 14 are adjusted. The gas in the exhibition storage device 1 is circulated through a route passing through the wet device (HC) 13, the manual valve 6, the flow meter 11, and the manual valve 4. Oxygen in the exhibition storage device 1 is adsorbed by an oxygen adsorbent in the adsorption device 14 with an appropriate circulation flow rate to reduce the oxygen concentration in the gas, and the humidity in the humidity control device 13 is reduced to humidity. adjust. The circulation flow rate is, for example, 0.5 l / min. In this case, it takes about 24 hours to reduce the oxygen concentration to 0.1% or less. After the oxygen concentration is reduced to 0.1% or less, the manual valves 4 and 5 are closed to shift to a long-term storage state. The difference between the gas pressure and the atmospheric pressure in the exhibition storage device 1 and the oxygen concentration are regularly observed.

When nitrogen gas is injected into the exhibition storage device 1, the gas pressure in the exhibition storage device 1 becomes higher than the external atmospheric pressure, which may cause damage to the exhibition storage device 1. Further, since the gas is circulated in a sealed state and the residual oxygen is absorbed by the oxygen adsorption device 14, the gas pressure in the display storage device 1 becomes lower than the external atmospheric pressure, and the display storage device 1 is damaged as described above. Fear arises. In order to alleviate this differential pressure, telescopic bellows 25 and 26 are arranged on the inside and outside of the exhibition storage device 1. For the differential pressure that cannot be covered by the bellows 25, 26, a differential pressure regulator (DPR) 9 having the ability to make the differential pressure between the gas pressure in the exhibition storage device 1 and the atmospheric pressure equal to or lower than an arbitrary pressure is used. . This device is composed of a differential pressure sensor and an electromagnetic valve. For example, when the set value of the differential pressure sensor (DPS) in the differential pressure adjusting device (DPR) 9 shown in FIG. 2 is set to +1 kPa and −1 kPa, the gas pressure in the exhibition storage device 1 increases and the differential pressure becomes 1 kPa. When reaching, the electromagnetic valve A operates, the gas in the exhibition storage device 1 is discharged from the gas discharge pipe 21 through the gas pressure adjusting pipe 17, and the differential pressure is lowered. When the gas pressure in the exhibition storage device 1 decreases due to oxygen adsorption and the differential pressure becomes −1 kPa, the electromagnetic valve B operates and nitrogen gas is injected into the display storage device 1 from the gas pressure adjusting pipe 17 through the gas introduction pipe 24. Differential pressure is relieved. Although the differential pressure rises due to the temperature change around the exhibition storage device 1, the bellows 25 and 26 and the differential pressure adjusting device 9 can cope with this case.

Embodiment As shown in FIG. 1, an oxygen adsorption tank, a humidity control tank and a small vacuum pump are used to circulate the gas and adsorb the permeating oxygen. There is no device or the like, and there is almost no heat generation of power. This system is a system that does not generate power noise during operation and heat generation.

The present invention is a preservation system that keeps valuable cultural assets as well as old documents and valuable slips by sealing with nitrogen gas in the atmosphere with special consideration to the labor costs of medicine preservation, health and the environment. Since conventional compressors are not used, the system noise and the need for maintenance are minimized, and the demand can be expanded.

It is sectional drawing which shows embodiment of this invention. It is a figure inside a differential pressure regulator (DPR) explaining the codes A and B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cross-sectional view of an exhibition preservation apparatus 2 Plan view of an oxygen removal / humidity control system 3-8 Manual valve 9 Differential pressure adjustment device 10 Nitrogen gas cylinder 11 Flow meter 12 Oxygen concentration meter 13 Humidity control device 14 Oxygen adsorption device 15 Air pump 16 Gas Pipe for press fitting 17 Gas pressure adjusting pipe 18 Gas circulation pipe 19 Pipe for differential pressure sensor 20, 21 Gas exhaust pipe 22, 23 Oxygen concentration measuring pipe 24 Gas introduction pipe 25, 26 Bellows

Claims (3)

Oxygen adsorption device containing oxygen adsorbent, humidity control device containing humidity conditioning agent, pipe for injecting nitrogen gas into transparent acrylic or transparent glass case, pipe for circulating and exhausting gas, small size It consists of a nitrogen gas cylinder, an internal pressure regulator, an oxygen concentration meter, and a small vacuum pump. After nitrogen gas is injected into the case, the small vacuum pump circulates the gas through the system path consisting of the case, oxygen adsorber, and humidity controller. Oxygen removal / conditioning system that removes residual oxygen in the case and adjusts humidity. Made of plastic such as metal bellows with the ability to flexibly adjust the pressure drop and rise in the case or in the middle of the pipe, rubber or fluororesin bellows that are difficult to deteriorate, and polyethylene that is difficult to pass oxygen 2. The system according to claim 1, further comprising a pressure adjusting device using a bellows and having an ability to suppress a differential pressure between the internal atmospheric pressure and the external atmospheric pressure to an arbitrary value or less. The system according to claim 1, wherein the system can be connected to a plurality of storage cases by attaching to a highly airtight storage case to enable long-term storage in an oxygen-free state.

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