KR101802186B1 - Online dissolved gas analysis system - Google Patents

Abstract

The present invention includes: a gas chromatograph (GC) analysis part detecting dissolved gas which is separated from a mixture of the dissolved gas with carrier gas through a column; a membrane module including an oil chamber to pass oil, and extracting and collecting the dissolved gas from the oil chamber into a gas chamber which is isolated from the oil chamber through a membrane; an oil supply discharge part supplying the oil to the oil chamber to discharge the oil; a gas supply discharge part supplying calibration gas to the gas chamber to discharge a mixture of the dissolved gas in the gas chamber to discharge the mixture and the calibration gas; a sample loop filled with the mixture of the dissolved gas discharged by the gas supply discharge part; and a switching part making a switch to fill the sample loop with the mixture of the dissolved gas which is discharged by the gas supply discharge part, or making a switch to supply the mixture of the dissolved gas in the sample loop and the carrier gas to the column by supplying the carrier gas to the sample loop. Accordingly, the present invention is capable of increasing the efficiency of extraction by combining a membrane method with a vacuum method, analyzing all of the eleven types of dissolved gas, which are monitored during the diagnosis of a transformer, through one detector, discovering a column condition to separate all of the eleven types of dissolved gas under an isothermal condition during GC analysis, and analyzing the gas at a higher maximum detection limit of the detector through a dilution chamber.

Description

Online dissolved gas analysis system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-line gas analyzing system, and more particularly, to an on-line gas analysis system for enhancing extraction efficiency of a gas stream and improving reliability of analysis of gas stream.

Generally, if a transformer breakdown occurs, it leads to a big accident such as a large scale power outage caused by a system accident and a large loss is inevitable. Therefore, the condition diagnosis of the transformer is very important in terms of neglecting an accident.

This method is used to diagnose an abnormality that occurs when an overload operation of a large-capacity transformer is being performed. There is a gas analyzer in a transformer in which a gas generated in the insulating oil inside the transformer (hereinafter referred to as a gas in oil) is detected.

Transformer In-line gas analyzer uses an off-line technique to stop the transformer in operation and detect and analyze the dielectric oil sample in the transformer for the detection and analysis of gas in the stream. However, this method requires periodically stopping the transformer, and there has been a problem of inaccuracies of the sample due to air inflow and gas loss in detecting the dielectric oil sample.

In order to solve such a conventional problem, Korean Patent Laid-Open No. 10-2013-0003764, entitled " Transformer oil gas analyzer "has been proposed, which is a device for detecting a gas in the oil in the transformer, A gas analyzer, comprising: a gas detection sensor in direct contact with the gas stream; A gas sensor mounting portion for covering the upper portion of the gas detection sensor and storing the gas in the upper portion of the transformer so that the flowing gas does not leak to the outside of the transformer; And a gas shutoff cap that includes a transformer valve and is detachably coupled to the gas sensor mounting portion and lifts up the wet gas to the upper portion when the transformer valve is operated.

However, the prior art has a limitation in increasing extraction efficiency of oil gas from oil, and it is difficult to analyze various kinds of gas oil by one detector, and it has a problem that it is difficult to raise the maximum detection limit.

In order to solve the problems of the prior art as described above, the present invention can improve the extraction efficiency of the gas in the gas and analyze all the 11 types of gas in the gas to be monitored in the transformer diagnosis by one detector, It is aimed to make it possible to find the column condition that can isolate all 11 kinds of gas in the gas, and to increase the maximum detection limit of the detector to broaden the concentration range to be analyzed.

Other objects of the present invention will become readily apparent from the following description of the embodiments.

According to an aspect of the present invention, there is provided a gas chromatograph (GC) analysis method for detecting a gas stream separated by a column from a mixture of gas streams supplied together with a carrier gas by a single detector part; A membrane module in which an oil chamber is provided to allow oil to pass therethrough and a gas gas is extracted from the oil chamber through the membrane to the gas chamber isolated by the membrane in the oil chamber; An oil supply / discharge unit for supplying oil to the oil chamber and discharging the oil; A gas supply and discharge unit for supplying a calibration gas to the gas chamber to cause a mixture of the inert gas in the gas chamber to be discharged together with the calibration gas; A sample loop in which a mixture of gas in the gas discharged by the gas supply / discharge portion is filled; And a mixture of the gas stream discharged by the gas supply / discharge section is switched to fill the sample loop, or a mixture of the gas in the gas filled in the sample loop is supplied to the column, together with the carrier gas, And a switching unit for switching the supply source to be supplied to the on-line gas analyzing system.

The GC analysis section supplies a carrier gas in which a discharge gas whose flow rate is controlled by the first flow controller is supplied to the detector and a flow rate of which is controlled by the second flow controller is supplied to the column, And can be connected in series.

The membrane module is provided with a hollow membrane so as to vertically pass through the inside of the body, and an upper end and a lower end of the membrane are respectively fixed by fixing rings fixed to the upper and lower ends of the inner surface of the body, Wherein the oil chamber and the gas chamber formed on the outer side and the inner side of the oil chamber are separated from each other by the fixed ring and the direction of the oil passing through the oil chamber by the oil supply / So that the directions of the gases passing through the chamber can be opposite to each other.

Wherein the oil supply / discharge unit includes an oil supply line for providing a path for supplying oil to the oil chamber; An oil pump installed in the oil supply line; A recovery line branched from the front end of the oil pump in the oil supply line and connected to a lower end of the gas chamber; An oil inlet valve installed at a side where the recovery line is branched from the oil supply line and used for recovery of oil to be leaked; A first oil breaker installed in the recovery line to prevent oil from entering the gas area; An oil discharge line for providing a path for oil to be discharged from the gas chamber; And an oil backflow prevention valve installed in the oil discharge line and blocking backflow of the oil.

Wherein the gas supply / discharge unit includes: a circulation line for circulating a mixture of the gas in the gas chamber to the sample loop; A gas pump installed to provide a pumping force for circulation of gas to the circulation line; A calibration gas container for supplying the calibration gas; A gas supply line connected from the calibration gas vessel to the front end of the gas chamber in the circulation line; And a third flow controller installed to control a flow rate of the calibration gas supplied to the gas supply line.

Wherein the gas supply / discharge portion includes: a gas connection line connected to supply a purge gas to a rear end of the third flow controller in the gas supply line; A fourth flow controller for controlling a flow rate of the calibration gas supplied through the gas connection line; A bypass line connected to the circulation line to bypass the membrane module; A second oil circuit breaker installed in the bypass line to prevent oil from entering the gas region; An exhaust line branched from the rear end of the gas pump in the circulation line; A restrictor installed in the exhaust line for increasing a pressure of a mixture of passing-through gas; And a plurality of open / close valves arranged to control the circulation of a mixture of the natural gas through the circulation line, the supply of the calibration gas to the circulation line, and the discharge of the mixture of the natural gas through the exhaust line.

According to the on-line gas analysis system of the present invention, unlike the conventional single extraction method, it is possible to increase the extraction efficiency of the gas in the gas by combining the membrane method and the vacuum method, and 11 kinds of gas It is possible to analyze all of them by one detector. In GC analysis, it is possible to find the column condition that can isolate all 11 kinds of gas in the isothermal condition. And, by using a dilution chamber, So that the concentration range for analyzing can be widened.

1 is a block diagram illustrating an online oil gas analysis system according to one embodiment of the present invention,
FIG. 2 is a view showing an on-line gas analyzing system according to one embodiment of the present invention, and shows a state of extracting gas in the gas stream.
FIG. 3 is a view showing an on-line gas analyzing system according to one embodiment of the present invention, and shows a state in which a gas is injected into a gas.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in detail in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but is to be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention, And the scope of the present invention is not limited to the following examples.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant explanations thereof will be omitted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram illustrating an online on-line gas analysis system according to an embodiment of the present invention, and shows a standby state. FIG.

1, an online on-line gas analysis system 100 according to an embodiment of the present invention includes a GC (Gas Chromatograph) analysis unit 110, a membrane module 120, an oil supply / discharge unit 130, A discharge loop 140, a sample loop 160, and a switch 170.

The GC analysis section 110 allows the single gas detector 113 to detect the gas stream separated by the columns 111 and 112 from the mixture of gas streams supplied together with the carrier gas. Here, the columns 111 and 112 can separate the analyte from the atmosphere using, for example, the difference in the moving speed of each component contained in the atmosphere, and this separation process can be divided into two stages: distribution between the mobile phase and the stationary phase, adsorption, . For example, a porous adsorbent for adsorbing the analyte can be filled in the inside. The columns 111 and 112 may be changed according to an analytical target substance to be separated, for example, a gas in the gas, and may be configured as a plurality of coupled states when necessary, and may be configured as a direct heating system. As the detector 113, various detectors may be used depending on the analyte such as H ₂ , air, CH ₄ , CO, and the like.

The GC analysis unit 110 can supply a discharge gas to the detector 113 through which the flow rate is controlled by the first flow controller 182 through the first line 191, A carrier gas whose flow rate is controlled by the second flow controller 183 can be supplied to the columns 111 and 112 via the second line 192 branching from the first and second flow controllers 191 and 191, And the third and fourth lines 193 and 194 connected to each other by the switching unit 170 so that a pair of columns 111 and 112 can be connected in series. Here, the discharge gas and the carrier gas may be, for example, helium gas supplied from the helium cylinder 181, respectively.

The membrane module 120 is provided with an oil chamber 121 through which the oil passes and a gas chamber 123 isolated from the oil chamber 121 by the membrane 122 is connected to the oil chamber 121 through the membrane 122 The gas is extracted and collected.

The membrane module 120 may include a hollow membrane 122 to be vertically passed through the inside of the body 124 and may be fixed to the upper and lower ends of the inner surface of the body 124, The upper and lower ends of the membrane 122 can be fixed by the fixing rings 125 and 126. The oil chamber 121 and the gas chamber 123 formed on the outer side and the inner side of the membrane 122, respectively, And the directions of the oil passing through the oil chamber 121 and the directions of the gas passing through the gas chamber 123 by the oil supply and discharge unit 130 and the gas supply and discharge unit 140 are mutually So that the extraction efficiency of the gas from the oil can be increased while having a compact structure.

The oil supply / discharge unit 130 supplies oil to the oil chamber 121 to be discharged. The oil supply and discharge unit 130 includes an oil supply line 131 for providing a path for supplying oil to the oil chamber 121 and an oil supply line 131 for supplying oil to the oil supply line 131, A recovery line 133 branched from the front end of the oil pump 132 at the oil supply line 131 and connected to the lower end of the gas chamber 123, An oil inlet valve 134 installed on the side where the recovery line 133 branches from the line 131 and used for recovery of the oil to be leaked and an oil inlet valve 134 installed on the recovery line 133 A first oil circuit breaker 135 for preventing oil from entering the gas region, an oil discharge line 136 for providing a path for oil to be discharged from the gas chamber 123, And an oil backflow prevention valve 137 for blocking backflow of the oil. Further, the oil discharge line 136 may be provided with a first pressure gauge 138 to measure the pressure of the discharged oil.

The gas supply / discharge unit 140 supplies a calibration gas to the gas chamber 123 to allow the mixture of the gas in the gas chamber 123 to be discharged together with the calibration gas. Here, the calibration gas may be a variety of gases, such as purge gas, which helps in the analysis of the gas in the stream or has no effect, and satisfies this.

The gas supply and discharge unit 140 includes a circulation line 141 for circulating the mixture of the gas in the gas in the gas chamber 123 to the sample loop 160, A gas pump 142 installed to reduce the pressure inside the membrane module 120 to atmospheric pressure or less to provide a pumping force for circulation of the calibration gas container 143, a calibration gas container 143 for supplying a calibration gas, A gas supply line 144 connected to the front end of the gas chamber 142 in the circulation line 141 and a third flow controller 145 installed to control the flow rate of the calibration gas supplied to the gas supply line 144 ).

The gas supply and discharge unit 140 includes a gas connection line 146 connected to supply purge gas to the rear end of the third flow controller 145 in the gas supply line 144, A fourth flow controller 147 for controlling the flow rate of the purge gas, a bypass line 148 connected to the circulation line 141 to bypass the membrane module 120, A second oil circuit breaker 149 for preventing the oil from invading the gas region, an exhaust line 151 branched from the rear end of the gas pump 142 in the circulation line 141, A restrictor 152 which is made up of a tube having a small inner diameter so as to increase the pressure of the mixture of passing gas through which the flow of gas is controlled so as to easily control the pressure by keeping the flow rate low; The mixture circulation, the circulation line 141, An on-off valve (153154155156157158159) that are provided in plurality so as to control the supply and discharge of the water-in-oil mixture gas through the exhaust line 151 may further include. The bypass line 148 may also be provided with a second pressure gauge 159 to measure the pressure of the mixture of gas in the gas and the pressure of the gas in the gas after extraction, have. Here, the purge gas may be, for example, helium gas supplied from the helium cylinder 181. [ Similarly to the first oil circuit breaker 135, the second oil circuit breaker 149 may be a level sensor for detecting a liquid.

Closing valves 153 and 154 installed at the front end and the rear end of the membrane module 120 in the circulation line 141 and the third opening and closing valves 153 and 154 installed at the gas supply line 144. The opening and closing valves 153 and 154, A fourth open / close valve 156 installed at the bypass line 148, a fifth open / close valve 157 installed at the rear end of the gas pump 142 in the circulation line 141, And a sixth opening / closing valve 158 installed in the second opening / closing valve 151.

The sample loop 160 allows the mixture of gas stream discharged by the gas supply / discharge unit 140 to be filled. The sample loop 160 may have various shapes and configurations of coils, vessels, etc. to accommodate an amount of atmosphere suitable for gas chromatographic analysis.

The switching unit 170 switches the supply of the gas mixture discharged from the gas supply and discharge unit 140 to the sample loop 160 or supplies the carrier gas to the sample loop 160 And the mixture of the filled gas is supplied to the columns 111 and 112 together with the carrier gas.

The switch 170 may be, for example, a 10-port 2-position valve. The first port 191 is connected to the first port 191, the second port 193 is connected to both ends of the third line 193, A third port and a tenth port to which both ends of the fourth line 194 are connected, a fourth port and a seventh port to which both ends of the sample loop 160 are respectively connected, and both ends of the circulation line 141 A fifth port, a sixth port, and an eighth port to which the second line 192 is connected, respectively.

For example, the online on-line gas analysis system 100 according to the present invention can be used in combination with a transformer, installed in the vicinity of a transformer, and used for detecting a gas in the oil generated in the insulating oil in the transformer. A casing 210 having an external appearance may be provided. The on line online gas analysis system 100 can be configured to operate without stopping the transformer and can receive the sensing signals of the pressure gauges 138, 159, 184 and 185 to calculate the respective pressures, (Not shown) for controlling the flow rate controllers 145, 147, 182 and 183, the switching unit 170, the oil pump 132, the gas pump 142 and the detector 113, But they may be performed by manual operation.

The operation of the on-line gas analyzing system according to the present invention will now be described.

1, in the system standby state, only the discharge gas and the carrier gas flow to the GC analysis section 110 side by the first flow controller 182 and the second flow controller 183.

2, the third and sixth open / close valves 155 and 158 are closed and the first, second, fourth and fifth open / close valves 153, 154, 156 and 157 are opened. By driving the gas pump 142, The pressure in the oil chamber 123 is lower than the atmospheric pressure, the mixture of the in-stream gas is circulated through the circulation line 141, and the oil pump 132 is driven to rotate the oil in the oil chamber 121 in the direction opposite to the mixture of the in- . At this time, since the extracted mixture of the flowing gas is circulated including the sample loop 160, a separate loading process is unnecessary.

3, a mixture of the inert gas in the sample loop 160 is injected into the columns 111 and 112 by driving the switch 170, and the mixture of the inert gas injected into the columns 111 and 112 is supplied to a predetermined inert gas And is supplied to the detector 113 and analyzed. The data analyzed by the detector 113 may be provided to the monitoring device by wire communication using a communication cable, or wireless communication using a wireless communication module such as Wi-Fi, Bluetooth, 3G, or LTE.

According to the present invention, unlike the conventional single extraction method, it is possible to increase the extraction efficiency by combining the membrane method and the vacuum method, and analyze all of the 11 kinds of oil in the gas to be monitored in the transformer diagnosis by using one detector In the GC analysis, it is possible to find the column condition that can isolate all 11 kinds of gas in the isothermal condition. In the dilution chamber, the maximum detection limit of the detector can be increased and the concentration range Can be widened.

Although the present invention has been described with reference to the accompanying drawings, it is to be understood that various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

110: GC analysis unit 111: first column
112: second column 113: detector
120: Membrane module 121: Oil chamber
122: Membrane 123: Gas chamber
124: body 125, 126:
130: Oil supply / discharge unit 131: Oil supply line
132: Oil pump 133: Collection line
134: Oil inlet valve 135: First oil circuit breaker
136: Oil discharge line 137: Oil backflow prevention valve
138: first pressure meter 140: gas supply / discharge unit
141: circulation line 142: gas pump
143: calibration gas container 144: gas supply line
145: third flow controller 146: gas connection line
147: fourth flow controller 148: bypass line
149: second oil circuit breaker 151: exhaust line
152: restrictor 153: first opening / closing valve
154: second open / close valve 155: third open / close valve
156: fourth opening / closing valve 157: fifth opening / closing valve
158: sixth opening / closing valve 159: second pressure measuring instrument
160: Sample loop 170:
181: Helium cylinder 182: first flow controller
183: second flow controller 184: third pressure meter
185: fourth pressure measuring instrument 191: first line
192: second line 193: third line
194: fourth line 210: casing

Claims (6)

A GC (Gas Chromatograph) analyzing unit for detecting a gas stream separated by a column from a mixture of the gas in the gas supplied together with the carrier gas by a single detector;
A membrane module in which an oil chamber is provided to allow oil to pass therethrough and a gas gas is extracted from the oil chamber through the membrane to the gas chamber isolated by the membrane in the oil chamber;
An oil supply / discharge unit for supplying oil to the oil chamber and discharging the oil;
A gas supply and discharge unit for supplying a calibration gas to the gas chamber to discharge a mixture of the inert gas in the gas chamber together with the calibration gas;
A sample loop in which a mixture of gas in the gas discharged by the gas supply / discharge portion is filled; And
A mixture of the gas stream discharged by the gas supply / discharge unit is switched to be filled in the sample loop, or a mixture of the gas stream filled in the sample loop is supplied to the column A switching unit for switching the supply to be supplied;
Lt; / RTI >
The membrane module comprises:
The upper and lower ends of the membrane are fixed by a fixing ring fixed to the upper and lower ends of the inner surface of the body, respectively, and the upper and lower ends of the membrane are fixed to the outer side and the inner side of the membrane, Wherein the oil chamber and the gas chamber formed respectively are separated from each other by the fixed ring, and the direction of the oil passing through the oil chamber by the oil supply / discharge portion and the gas supply / So that the direction of the gas is reversed. The method according to claim 1,
Wherein the GC analysis unit comprises:
A discharge gas whose flow rate is controlled by a first flow controller is supplied to the detector, a carrier gas whose flow rate is controlled by a second flow controller is supplied to the column, and the columns are connected in series , Online oil gas analysis system. delete The method according to claim 1,
The oil supply /
An oil supply line for providing a path for supplying oil to the oil chamber;
An oil pump installed in the oil supply line;
A recovery line branched from the front end of the oil pump in the oil supply line and connected to a lower end of the gas chamber;
An oil inlet valve installed at a side where the recovery line is branched from the oil supply line and used for recovery of oil to be leaked;
A first oil breaker installed in the recovery line to prevent oil from entering the gas area;
An oil discharge line for providing a path for oil to be discharged from the gas chamber; And
An oil backflow prevention valve installed in the oil discharge line and blocking backflow of oil;
And an on-line gas analysis system. The method according to claim 1,
The gas supply /
A circulation line through which a mixture of gas streams in the gas chamber is circulated to the sample loop;
A gas pump installed to provide a pumping force for circulation of gas to the circulation line;
A calibration gas container for supplying the calibration gas;
A gas supply line connected from the calibration gas vessel to the front end of the gas chamber in the circulation line; And
A third flow controller installed to control a flow rate of the calibration gas supplied to the gas supply line;
And an on-line gas analysis system. The method of claim 5,
The gas supply /
A gas connection line connected to supply a purge gas to the rear end of the third flow controller in the gas supply line;
A fourth flow controller for controlling a flow rate of the purge gas supplied through the gas connection line;
A bypass line connected to the circulation line to bypass the membrane module;
A second oil circuit breaker installed in the bypass line to prevent oil from entering the gas region;
An exhaust line branched from the rear end of the gas pump in the circulation line;
A restrictor installed in the exhaust line for increasing a pressure of a mixture of passing-through gas; And
A plurality of open / close valves arranged to control the circulation of the mixture of the gas in the oil through the circulation line, the supply of the calibration gas to the circulation line, and the discharge of the mixture of the gas in the gas through the exhaust line;
And an on-line gas analysis system.

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