JP5370836B2 - Steam property monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To sufficiently monitor steam property even when the steam is condensed and a quality of the condensate water generated at that time is measured without using special cooling water. <P>SOLUTION: In this steam property monitoring device 1 for monitoring properties of the steam S by condensing the steam S generated in a boiler by using a heat exchanging means, and measuring the quality of the condensate water W2 generated at that time by a water quality measurement instrument 4, the heat exchanging means is an air-cooling type cooler 3 for forcibly cooling the steam S by the air A in the atmosphere. When the air-cooling type cooler 3 is used, a heat transferring coefficient is small in comparison with when the water-cooling type cooler using the cooling water is used, and a flow rate of the condensate water is necessarily reduced, but a result nearly similar to that when the water-cooling type cooler is used, is achieved. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a steam property monitoring device that monitors the properties of steam generated in a boiler.

  Conventionally, various methods for estimating the amount of impurities contained in steam and the corrosiveness of steam by cooling the steam generated from the boiler and measuring the properties of the condensed water have been implemented.

  For example, in the vapor property monitoring apparatus disclosed in Patent Document 1, after sampling a sufficient amount of vapor, the vapor is cooled with cooling water to obtain condensed water having a temperature close to room temperature (25 ° C.). By measuring water quality stably, the properties of steam are accurately judged and evaluated. Moreover, in the monitoring apparatus for boiler condensate systems shown by patent document 2, the corrosiveness of steam is evaluated by condensing the vapor | steam received in the apparatus using cooling water, and immersing a test piece in the condensed water. ing.

JP 2007-93128 A JP-A-8-28803

  However, even in the case of the steam property monitoring device and the boiler condensate monitoring device, a large amount of stable cooling water is required to condense the steam. For this reason, when performing on-site tests in permanent installations or arbitrary periods using these devices, it is not easy to secure cooling water and it is not easy to secure a destination for cooling water disposal. There was a problem.

  In view of the above points, the present invention is a vapor property monitor that can sufficiently monitor the property of steam even when the water is condensed without using cooling water and the quality of the condensed water generated at this time is measured. An object is to provide an apparatus.

According to the first aspect of the present invention, the steam generated in the boiler is condensed using heat exchange means, and the quality of the steam is monitored by measuring the quality of the condensed water generated at this time with a water quality measuring device. A steam property monitoring device, wherein the heat exchanging means is an air-cooled cooler that forcibly cools the steam with air in the atmosphere , and the water quality measurement is performed upstream of the air-cooled cooler. The condensed water cooler which cools the vapor | steam introduce | transduced into the said air-cooling type cooler with the said condensed water after water quality is measured with the vessel is characterized by the above-mentioned.

In this invention, the steam from the boiler is cooled by the condensed water after the water quality measurement using the condensate cooler, and is forcedly cooled by the air in the atmosphere using the air-cooled cooler, It is converted into condensed water, and then the quality of the condensed water is measured by a water quality measuring device. When using an air-cooled cooler, the heat transfer coefficient is small and the flow rate of condensed water must be reduced compared to using a water-cooled cooler that uses cooling water. As a result, almost the same result can be obtained as when the water-cooled cooler is used.

The invention of claim 2, wherein the present invention is, in the case of the invention of claim 1, wherein, between the water quality measuring device and the air-cooled condenser, and agitated condensed water exiting from the air-cooling type cooler A uniform stirring cell is provided.

The amount of condensed water of the steam generated using an air-cooled cooler or the like is a relatively small flow rate, and is difficult to be stirred while flowing in the flow path, and the water quality tends to be biased. For this reason, using a stirring cell, a predetermined amount of condensed water was accumulated and stirred to achieve uniform water quality.

According to a third aspect of the present invention, in the case of the first or second aspect of the present invention, the gas in the condensed water discharged from the air-cooled cooler is interposed between the air-cooled cooler and the water quality measuring device. A degassing cell is provided for collecting and extracting the gas.

  The steam from the boiler contains nitrogen, etc. in a gas state. When the steam is cooled to condensate, some of these gases are not dissolved in the water and exist in the water in the gas state. There is also a case. For this reason, while using the degassing cell, the gas present in the condensed water was collected, and this gas was released to the outside to prevent the gas that adversely affects the water quality measurement from moving to the water quality measuring instrument side.

According to a fourth aspect of the present invention, in the case of the invention according to any one of the first to third aspects, the water quality measuring device includes boiler feed water, boiler can water, Alternatively , a signal transmission means is provided for transmitting a signal to a water treatment agent injecting apparatus for injecting the water treatment agent into at least one of the steams to improve the steam property.

  In this invention, along with the change in the vapor properties, a signal is sent to the water treatment agent injection device to increase or decrease the injection amount of the water treatment agent injected into the boiler feed water or the like, or the injection of the water treatment agent into the boiler feed water or the like. Start or stop.

  According to the first aspect of the present invention, since the heat exchange means for converting steam into condensed water is an air-cooled cooler, cooling water is unnecessary, and not only a cooling water source but also piping to the apparatus is not required. It becomes. For this reason, in this invention, the monitoring operation | work of a vapor | steam property can be facilitated.

Further, according to the present invention , the steam can be cooled not only by the air-cooled cooler but also by the condensed water cooler, so that the flow rate of the condensed water can be increased and the air-cooled cooler can be reduced in size. Can be achieved. Moreover, in this invention, since the used condensed water is used for the cooling medium of a condensed water cooler, the cooling efficiency of a vapor | steam can also be improved.

According to invention of Claim 2 of this invention, the bias | inclination of the water quality in the condensed water supplied to a water quality measuring device can be eliminated, and the water quality of condensed water can be measured accurately using a water quality measuring device. .

According to invention of Claim 3 of this invention, it can prevent that the gas which exists in condensed water adheres to the circumference | surroundings of the measurement part of a water quality measuring device, and falls a measurement precision.

According to the invention described in claim 4 of the present invention, the amount of the water treatment agent injected into the boiler feed water or boiler can water can be controlled in accordance with the change in the properties of the steam. The resulting corrosion can be quickly suppressed.

It is a flowchart which shows the vapor property monitoring apparatus which concerns on one embodiment of this invention. The graph of the dissolved oxygen concentration measured with the vapor | steam property monitoring apparatus using an air-cooling-type cooler is shown. The graph of the dissolved oxygen concentration measured with the conventional vapor | steam property monitoring apparatus using a water cooling type cooler is shown.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a vapor property monitoring apparatus according to an embodiment of the present invention.
The steam property monitoring device 1 cools and condenses the steam S generated in the boiler, and monitors the quality of the steam S while determining the quality (quality) of the condensed water W2 by measuring the quality of the condensed water W2. For example, when the property of the steam S deteriorates, the amount of the water treatment agent injected is changed in the water treatment agent injection device to improve the steam property.

  As shown in FIG. 1, the steam property monitoring device 1 includes a condensate cooler 2, an air-cooled cooler 3 that is a heat exchange means, a water quality measuring device 4, a steam line 5, and a primary condensate water line. 6, a secondary condensed water line 7, and a measured condensed water line 8. In addition, although the piping size in the steam line 5, the primary condensate water line 6, and the secondary condensate water line 7 is a stainless steel 1/16 inch pipe (inner diameter 0.8mm), it is very thin. The piping size of the measured condensed water line 8 is a carbon steel ½ inch pipe, which is relatively large.

  As shown in FIG. 1, the condensate cooler 2 cools the steam S with measured condensate W3 to produce primary condensate W1, and includes a casing 20, a casing lid 21, heat, and the like. It is comprised from the exchange part 22. FIG. The casing 20 stores the measured condensed water W3 and brings the measured condensed water W3 into contact with the heat exchanging unit 22 installed inside. The overflow pipe 20a of the measured condensed water W3 is provided on the upper side. Is provided.

  The casing lid 21 covers the upper part of the casing 20 whose upper end is opened easily, and is connected to the steam line 5, the primary condensed water line 6, and the secondary condensed water line 7 on the upper surface side. Is provided. The casing lid 21 is provided with a vent pipe 21 a for opening to the atmosphere on the upper side, and a nozzle 21 b connected to the measured condensed water line 8 on the lower side. The heat exchanging unit 22 exchanges heat between the steam S and the measured condensed water W3, and has an inlet side connected to the steam line 5 and an outlet side connected to the primary condensed water line 6. This heat exchange part 22 is formed from a thin stainless steel tube.

  The air-cooled cooler 3 forcibly cools the primary condensate water W1 with air A in the atmosphere to produce secondary condensate water W2 for water quality measurement. The air blower 30, the duct 31, the heat transfer The coil 32 is configured. The inlet side of the heat transfer coil 32 housed in the duct 31 is connected to the primary condensed water line 6, and the outlet side is connected to the secondary condensed water line 7. The blower 30 is attached to one end side of the duct 31, that is, the outlet side of the heat transfer coil 32, and the air A from the blower 30 is discharged from the other end side of the duct 31, that is, the inlet side of the heat transfer coil 32. Is open for.

The heat transfer coil 32 has, for example, an inner diameter of 0.1 to 2.0 mm (preferably 0.5 to 1.0 mm) and a length of 5 to 20 m in consideration of heat transfer and pressure loss. A thin tube is used. Moreover, the thing with an air volume of 0.3-0.4 m < ³ > / min is used for the air blower 30, for example.

  As shown in FIG. 1, the water quality measuring device 4 includes a measurement unit 4A and a display transmission unit 4B. The measurement unit 4A measures various water qualities of the secondary condensed water W2, for example, in this embodiment, dissolved oxygen concentration (DO), electrical conductivity (EC), and pH. In the measurement unit 4A, a DO measurement unit 42 and an EC measurement unit 43 are provided in the first measurement cell 40, and a pH measurement unit 44 is provided in a second measurement cell 41 communicating with the first measurement cell 40. Is provided. In the measurement unit 4 </ b> A, the first measurement cell 40 is connected to the secondary condensed water line 7, and the second measurement cell 41 is connected to the measured condensed water line 8.

  The display transmission unit 4B receives a measurement signal from the measurement unit 4A, displays the dissolved oxygen concentration value, the electrical conductivity value, and the pH value measured by the measurement unit 4A, and records these values. It is. Moreover, this display transmission part 4B is based on the measurement signal from the measurement part 4A to the water treatment agent injection | pouring apparatus which inject | pours the water treatment agent into at least 1 place in boiler feed water, boiler can water, and steam, It has signal transmission parts 45, 46 and 47 which emit signals for controlling these water treatment agent injection devices.

  That is, the signal transmission units 45, 46, and 47 of the display transmission unit 4B increase the injection amount of the water treatment agent into the water treatment agent injection device or the necessary water treatment agent injection device if the properties of the steam S deteriorate. When the steam S is improved, the signal for reducing the amount of the water treatment agent injected into the water treatment agent injection device or stopping the operation of the unnecessary water treatment agent injection device. To emit.

  The steam line 5 cools the steam S on the boiler side, specifically the steam S from the branch pipe side for the pressure gauge 101 provided in the steam header 100 of the boiler, as shown in FIG. It is a line for taking in to the container 2 side. In the pipe of the steam line 5, a pressure reducing valve 50, an electromagnetic valve 51, and a filter 52 are provided along the flow of the steam S, and a flushing valve 53 is provided in front of the pressure reducing valve 50. It has been.

  The secondary condensed water line 7 is a line for sending the secondary condensed water W2 to the measuring unit 4A side of the water quality measuring device 4, and a thermostat 70 is provided along the flow of the secondary condensed water W2 in the piping of this line. And a stirring gas venting cell 72 are provided. The thermostat 70 is a bimetal type, and prevents high-temperature condensed water and steam from flowing into the measuring unit 4A side of the water quality measuring device 4, and at the same time, when the temperature of the secondary condensed water W2 reaches a high temperature of a predetermined value or more, This is for closing the solenoid valve 51 in the steam line 5.

  The stirring gas vent cell 72 stores a certain amount of secondary condensed water W2 inside, discharges the gas in the secondary condensed water W2 to the outside, and stirs the accumulated secondary condensed water W2. This is to make the properties uniform. The stirring gas vent cell 72 has a shape in which the upper portion of the main body portion 72a is gradually narrowed so that the gas can be easily degassed. Is provided. A stirrer 72d is attached to the lower end of the main body 72a of the stirring gas vent cell 72 so that the secondary condensed water W2 in the main body 72a can be stirred by the blades Y.

  The primary condensed water line 6 is for supplying the primary condensed water W1 generated in the condensed water cooler 2 to the air-cooled cooler 3, and the measured condensed water line 8 is the measured condensed water. W3 is supplied to the condensate cooler 2 from the measuring unit 4A of the water quality measuring device 4.

Next, the function and effect of the vapor property monitoring apparatus 1 will be described.
In this steam property monitoring device 1, most of the pipe size is a thin tube of 1/16 inch and is likely to be clogged. Therefore, it is necessary to sufficiently remove foreign matters in the steam S on the steam header 100 side. For this reason, when the vapor S is taken in, sufficient flushing is performed using the valve 53 or the like, and foreign matters in the vapor S are removed by the filter 52 during the measurement. Further, when taking in the steam S, the blower 30 of the air-cooled cooler 3 is operated, and the stirrer 72d of the stirring gas venting cell 72 is operated. Further, cooling water is put in the condensed water cooler 2 in advance.

  For example, after the steam S having a pressure of 0.7 MPa is taken into the steam line 5 through the pressure reducing valve 50 and the steam S is passed through the condensate cooler 2 to be converted into the primary condensate W1, this primary condensate is obtained. W1 is passed through the air-cooled cooler 3 and changed to secondary condensed water W2 having a temperature lower than that of the primary condensed water W1. And after passing this secondary condensed water W2 through the stirring degassing cell 72 and the water quality measuring device 4, this secondary condensed water W2, ie, the measured condensed water W3, is supplied to the condensed water cooler 2. In this case, the secondary condensed water W2 is cooled to a temperature close to room temperature (for example, 25 ° C.), and the pressure is also reduced to a pressure close to atmospheric pressure, depending on the temperature of the outside air.

  The above operation is continued for a certain period of time, and a necessary amount of the secondary condensed water W2 is accumulated in the stirring gas venting cell 72 and the like, and the cooling medium in the condensed water cooler 2 is used as the secondary condensed water W2 (measured condensed water). Replace with W3). During this time, the secondary condensed water W2 in the main body 72a of the stirring gas venting cell 72 is stirred uniformly by the stirrer 72d and supplied to the measuring section 4A side of the water quality measuring instrument 4. Further, by operating the valve 72b of the stirring gas release cell 72 at regular time intervals, the gas stored in the upper end portion of the main body 72a is discharged to the outside through the atmosphere release pipe 72c.

  When the temperature of the secondary condensate water W2 reaches a constant value close to room temperature, the operator operates the water quality measuring device 4 to measure the dissolved oxygen concentration in the secondary condensate water W2 and the secondary by the measuring unit 4A. The electrical conductivity and pH of the condensed water W2 are measured, and these measured values are displayed and recorded on the display transmitter 4B. Subsequently, the worker monitors the property of the steam S while checking the water quality of the secondary condensed water W2 indicated by the display transmission unit 4B. Further, when the water quality of the secondary condensate W2 is reduced, the display transmission unit 4B issues a signal to a water treatment agent injection device (not shown) and assumes that the property of the steam S has decreased, The amount of the water treatment agent injected into the boiler can water is increased, and the quality of the steam S is improved.

  As described above, the steam property monitoring device 1 uses the air-cooled cooler 3 for cooling the steam S, and it is not necessary to use cooling water as in the conventional device. The property of the steam S generated in the boiler can be easily and quickly monitored, and there is no problem with the treatment of the cooling water after use. Further, the steam property monitoring device 1 can monitor the property of the steam S from the boiler even in a place where there is no cooling water, and can also reduce the monitoring cost because the cooling water is not used. In addition, in this vapor property monitoring apparatus 1, compared with the conventional monitoring apparatus using a water-cooled cooler, the amount of condensed water of the steam S must be reduced in order to avoid an increase in the size of the apparatus. The quality of the measured condensate does not change.

  In addition, the steam property monitoring device 1 includes the condensate cooler 2 so that the measured condensate W3 can be used for cooling the steam S, so that the steam S can be efficiently cooled. The air-cooled cooler 3 can be downsized, and the flow rate of the secondary condensed water W2 can be increased.

  Further, the vapor property monitoring device 1 is provided with a stirring gas venting cell 72 to secondary-condensate a gas such as nitrogen present in a small amount in the vapor S that could not be dissolved during the condensation of the vapor S. Since it is removed from the water W2, these gases adhere to the DO measuring unit 4 and the EC measuring unit 43 of the water quality measuring instrument 4, and the trouble that the dissolved oxygen concentration and electrical conductivity cannot be measured correctly is avoided. can do.

  In addition, in this steam property monitoring device 1, the flow rate of the condensed water (the flow rate of the secondary condensed water W2) that can be supplied to the water quality measuring device 4 is cooled due to the performance of the cooler (air-cooled cooler 3) that condenses the steam. Since the amount is considerably reduced as compared with the conventional one using water, the secondary condensate water W2 is less likely to be agitated, and the secondary condensate water W2 is likely to be uneven in water quality. However, in this steam property monitoring device 1, the stirring degassing cell 72 is provided, and the secondary condensed water W2 is stirred in a state where a certain amount of the secondary condensed water W2 is stored in the cell 72. The secondary condensed water W2 supplied to the vessel 4 is not biased in water quality, and the water quality measuring device 4 can measure the average quality of the secondary condensed water W2.

  Furthermore, in this steam property monitoring apparatus 1, since the signal transmission parts 45, 46 and 47 which send a signal to the water treatment agent injection device are provided in the display transmission part 4B of the water quality measuring instrument 4, the property deterioration of the steam S, etc. On the other hand, the necessary water treatment agent can be quickly injected into the boiler feed water and boiler can water, etc., and the rapid improvement of the properties of the steam S, that is, the rapid prevention of corrosion due to the steam S and condensate. Can be planned.

  In this embodiment, the steam S is changed to 100% condensed water (primary condensed water W2) at the outlet of the condensate cooler 2, but the steam S may be partially mixed. Of course.

  The water quality measured by the water quality measuring device 4 includes dissolved oxygen concentration, electrical conductivity, pH value, hardness component, absorbance, chromaticity, silica concentration, chloride ion concentration, potassium ion concentration, sodium ion concentration, ORP value. , May be at least one of the TOC values.

  Further, in the vapor property monitoring device 1, the condensed water cooler 2 may not be provided, and the steam S may be cooled only by the air-cooled cooler 3 to be condensed water.

  2 and 3 show the dissolved oxygen concentration (DO (mg / L)) in the condensed water of steam S generated from one small once-through boiler having a pressure of 0.7 MPa. The result of having measured simultaneously with the conventional steam property monitoring apparatus (for example, what is shown by patent document 1) which used the cooling water for cooling of the steam | steam S is shown. FIG. 2 shows a case in which the flow rate of the condensed water is measured using the steam property monitoring device 1 and FIG. 3 shows a case where the flow rate of the condensed water is large (for example, a number compared with the case of the steam property monitoring device 1). Double the flow rate), measured with a conventional vapor property monitoring device. The data in FIG. 2 and FIG. 3 show the results output to the data logger at 1 minute intervals. In addition, the dissolved oxygen concentration in FIGS. 2 and 3 is low because the oxygen scavenger is injected into the boiler feed water, and the dissolved oxygen concentration is high in FIGS. 2 and 3. Shows a state in which the injection of the oxygen scavenger into the boiler feed water is stopped.

  When this vapor property monitoring device 1 is used, in the state where the oxygen scavenger is injected, although the peak height is slightly different from the case where the conventional vapor property monitoring device is used, As for, the dissolved oxygen concentration measured using this vapor property monitoring apparatus 1 is substantially in agreement with the case where the conventional vapor property monitoring apparatus is used. That is, FIGS. 2 and 3 show that the property of the steam S can be accurately monitored even when the steam property monitoring device 1 is used.

1 Steam property monitoring device 2 Condensate cooler 3 Air-cooled cooler (heat exchange means)
4 Water quality measuring device 45, 46, 47 Signal transmission part (signal transmission means)
72 Stirring air release cell (stirring cell, degassing cell)
S steam W2 secondary condensate (condensate)

Claims (4)

A steam property monitoring device that monitors the properties of the steam by condensing the steam generated in the boiler using a heat exchange means, and measuring the quality of the condensed water generated at this time with a water quality measuring device,
After the heat exchange means is an air-cooled cooler that forcibly cools the steam with air in the atmosphere , and the water quality is measured by the water quality meter upstream of the air-cooled cooler. A steam property monitoring device , comprising: a condensed water cooler for cooling the steam introduced into the air-cooled cooler with the condensed water . The steam according to claim 1 , wherein a stirring cell is provided between the air-cooled cooler and the water quality measuring device to stir and homogenize the condensed water from the air-cooled cooler. Property monitoring device. Between the water quality measuring device and the air-cooling type cooler according to claim 1, characterized in that there is provided a degassing cell for pulling collect condensation water gas discharged from the air-cooling type cooler or 2. The vapor property monitoring apparatus according to 2. The water quality measuring device transmits a signal to a water treatment agent injecting device that injects the water treatment agent into at least one of boiler feed water, boiler can water, or steam based on the measurement result of the water quality. 4. The vapor property monitoring apparatus according to claim 1 , further comprising a signal transmission means for improving the property.

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