JPS5930057A - Diaphragm type gas electrode support apparatus - Google Patents

Abstract

PURPOSE:To enable the measurement of the concentration of carbon dioxide in the exhaust gas during the fermentation process by protecting the opening of a cylinder housing a diaphragm type gas electrode with a heat resistant gas permeating membrane for permeating a gas to be inspected and a porous sheet made of a metal material impervious to a liquid or a gas to be inspected. CONSTITUTION:The opening of a cylinder made of a pressure and heat resistant material such as stainless steel pipe is closed with a gas permeating membrane 2 made of a silicone rubber film selectively permeating carbon dioxide and a porous sheet 3 impervious to a liquid and a gas to be inspected such as a stainless screen arranged outside the gas permeating membrane 2 with a slight clearance left from the gas permeating membrane 2. A diaphragm type gas electrode 10 is inserted into the cylinder 1 from the other end thereof so that a diaphragm 1 formed at one end thereof can be retained with a box nut 5 or the like as approaching the gas permeating membrane 2. When using this apparatus, one end of the cylinder 1 is inserted inside through a hole provided on the wall 7 or the like of a fermentation tank with, for example, an aid of a flange 8 provided almost in the center of the circumference thereof and fixed on the wall 7 with a box nut 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support device for a diaphragm type gas electrode used for measuring gas concentration in gas exhaust pipes and the like.

Generally, in the fermentation industry, it is important to measure the concentration of carbon dioxide gas dissolved in the culture solution in a fermenter during cultivation and the concentration of carbon dioxide gas in exhaust gas in order to observe the state during cultivation.

Conventionally, non-dispersive infrared carbon dioxide concentration meters have often been used to measure the carbon dioxide concentration in fermenters and exhaust gas during culture, but the equipment is expensive and the water vapor contained in the exhaust gas is often used. absorbs infrared rays, so it is necessary to take measures to compensate for the effects of this, and the measurement cell is easily contaminated and maintenance is troublesome. There are problems such as the inability to directly measure the concentration of gas.

Various attempts have been made to measure the carbon dioxide concentration in the exhaust gas or the dissolved carbon dioxide concentration in the culture solution during the fermentation process using the diaphragm electrode method, but the electrodes are exposed to high temperatures during the steaming sterilization process during the process. As a result of exposure, the gas absorption liquid inside the electrode becomes alkaline due to alkaline content eluted from the glass film of the glass electrode of the detection part, and the deterioration of the detection glass electrode and reference electrode is accelerated. However, the measurement was not easy and the accuracy was not good, so it was not possible to achieve sufficient results.

The Ig invention solves the above problem and provides a diaphragm type gas electrode that can be used by attaching it to the fermenter and its exhaust pipe passage even when the fermenter is sterilized by steaming at high temperature and high pressure. The purpose is to provide a support device.

In order to achieve this object, the present invention includes a gas permeable membrane that permeates a test gas and has heat resistance; The opening at one end is closed with a porous sheet made of a material that is not corroded by water, and a diaphragm-type gas electrode is inserted through the opening at the other end, and the diaphragm formed on one end surface of the diaphragm-type gas electrode is connected to the gas permeable membrane. A support device for a diaphragm gas electrode was constructed from a cylinder made of a heat-resistant and pressure-resistant material formed so as to be able to hold the diaphragm gas electrode in close proximity to each other, and a model having the same external shape as the diaphragm gas electrode. It is something.

To explain one embodiment of the device of the present invention, / is a cylinder made of a pressure- and heat-resistant material such as a stainless steel pipe, and the opening at one end is made of silicone rubber, for example, which selectively transmits the gas to be detected, such as carbon dioxide gas. A gas permeable membrane consisting of a membrane, a test liquid like a stainless steel mesh placed outside the gas permeable membrane with a small distance from the gas permeable membrane, and a gas permeable membrane with sufficient air permeability to avoid being attacked by the test gas. It is closed by a porous sheet 3 having strength. DA is a cap nut with a gas permeable membrane λ and a porous sheet f3 attached to one end of the cylinder.

The diaphragm type gas electrode 10 is inserted into the cylinder from the other end as shown in Fig. 2, and the diaphragm formed on one end surface of the cylinder / is held close to the gas permeable membrane by a cap nut S or the like. It is designed so that it can be done.

B shown in FIG. 1 is a model having the same external shape as the diaphragm gas electrode 10 shown in FIG. /2 allows it to be retained.

The cylinder is used by inserting one end thereof into the inside of the fermentation tank through a hole provided in the wall 7 etc. of the fermentation tank using a flange provided at the center of the outer periphery and fixing it to the wall 7 with a cap nut 9.

When sterilizing a fermenter, etc. at high temperature and pressure, insert model A into the cylinder as shown in Figure 1, and fix model B inside the cylinder with a blind lid for safety. Perform sterilization procedures. After the sterilization operation, the model 6 is replaced with a diaphragm type gas electrode/θ as shown in FIG. 2 to perform measurements during the fermentation operation.

When the sterilization operation is performed in this way, the pressure inside the wall 7 is applied to the gas permeable membrane through the porous sheet 3, but since there is a model A inside to support the gas permeable membrane, the gas This can prevent the permeable membrane from being damaged.

After heating and pressurizing, when the pressurized gas is discharged from inside the wall 7, the wall 7
As the temperature inside the tube decreases, the internal pressure inside the wall 7 may become lower than that inside the cylinder. At this time, the gas permeable membrane λ is sucked into the wall 7, but since the porous sheet 3 is placed on the outside, the gas permeable membrane is supported by this and the gas permeates through the suction. The membrane is protected.

As the porous sheet 3, other than stainless steel mesh, porous plastic or plastic mesh can be used. In the case of mesh, it is best to use one with a finer mesh than 20 mesh, and use stainless steel [1 mesh is better.

~JOO mesh level is best.

The reason for providing a gap between the gas permeable membrane and the porous sheet 3 is that if pressure is suddenly applied when they are in close contact, the gas permeable membrane will be pushed into the holes or mesh of the porous sheet 3. This is because the contact area may break, but if the gap is too large, when holding the diaphragm type gas electrode 10 as shown in Figure 1 to measure the fermentation status, etc., the indication response will be slow, and the pressure will increase. The maximum limit of the gap is 1/3, since the protective effect against

By using the device of the present invention, the diaphragm gas electrode can be used without being subjected to heat and pressure during heat sterilization of fermenters, etc., so the accuracy can be maintained without deterioration of the electrode during heat sterilization, and the gas The permeable membrane λ blocks the inside and outside and prevents bacteria and foreign matter from entering the inside of the fermenter, etc.

Furthermore, since the gas permeable membrane can be protected against pressure by the model 6 and the porous sheet 3, a gas permeable membrane with quick response and high accuracy can be used, and measurement with high sensitivity and accuracy can be performed.

[Brief explanation of drawings]

Both FIGS. 1 and 2 are longitudinal cross-sectional views of the electrode support device according to the present invention attached to the wall of a fermentation tank or the like. /...Cylinder, λ...Gas permeable membrane, 3...Porous sheet, q
1st night: bag nut, 6: model, 7: wall, g...7 lunge, wa... bag nut, 10: diaphragm gas electrode, //
... septum, /λ... blind lid. Applicant Toa Denpa Kogyo Co., Ltd.

Claims (1)

[Claims] (1) A gas permeable membrane that allows the test gas to pass through and has heat resistance, and a porous sheet made of a material that is not attacked by the test liquid and the test gas, which is placed at a distance from the gas permeable film and outside the gas permeable film. Then, the opening at one end is closed, and the diaphragm gas electrode is inserted through the opening at the other end, and the diaphragm gas electrode is closed with the diaphragm formed on one end surface of the diaphragm gas electrode close to the gas permeable membrane. A diaphragm-type gas electrode support device comprising a cylinder made of a pressure- and heat-resistant material formed to be able to hold the diaphragm-type gas electrode, and a model having the same external shape as the diaphragm-type gas electrode.