JP2010144947A - Condensation water quality monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for monitoring inclusion of impurities from a boiler and a steam use facility to condensation with good sensitivity. <P>SOLUTION: Part of condensation discharged from the steam use facility 4 is distributed from an introduction pipe 6, is set to have set temperature via a heat exchanger 11 and an air cooling column 13, and then is introduced to a measuring instrument 17 to measure properties. The measurement result is sent from the measuring instrument 17 to a control means 20. When the measurement result exceeds a reference value, a signal is transmitted from the control means 20 to valves 5a, 7a, 8a, and an alarm is transmitted to a control center. Thus, the valve 5a is closed and the valve 7a is opened. The condensation discharged from the steam use facility 4 is not supplied to raw water piping 1 and is discharged to outside of a system from water discharge piping 7. An opening of the valve 8a is increased, so as to increase the chemical feeding amount of water treatment agent from piping 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an apparatus for monitoring the quality of condensate water formed by condensation of steam generated in a boiler.

  Impurities in the boiler feed water can cause scale in the boiler.

  For example, if the boiler feedwater contains substances with very low solubility, that is, hardness components such as calcium and magnesium, insoluble solids are generated due to temperature rise and concentration, and some of them are sludge in the boiler. Or deposited on the boiler inner wall as a scale. In particular, on the heat transfer surface, the concentration becomes remarkable and the scaling is promoted.

  Also, if the boiler feedwater contains organic impurities, the organic impurities may concentrate in the boiler and cause corrosion, or carryover may occur in which the boiler water bubbles and enters the steam. There are things to do.

  Conventionally, in order to prevent such scale, corrosion, carry-over, and the like from occurring in a boiler, it has been practiced to remove the impurities in the raw water before supplying water to the boiler.

For example, Japanese Patent No. 4139938 describes that raw water is softened with a water softener and then supplied to a boiler. In the same issue, the hardness component concentration of raw water treated with this water softener is measured with a hardness detector, and when the hardness component concentration is higher than the set value, the supply of raw water to the boiler device is stopped. Yes.
Japanese Patent No. 4139938

  As energy-saving measures, condensate (drain) discharged by using steam produced in a boiler in a steam-using facility may be collected, and this condensate may be mixed with boiler raw water and used as boiler feed water. . As a result, it is possible to effectively use a high amount of heat of the condensate discharged from the steam use facility and reduce the amount of makeup water used.

  However, since such condensate passes through the boiler and the steam using facility, impurities from the boiler and the steam using facility may be mixed in the condensate. For example, a tube of a heat exchanger in a boiler or steam use facility has a broken hole, and impurities may be mixed into the condensate from the broken hole.

  Thus, when recovering condensate and mixing it with make-up water and using it as supply water, according to the method of monitoring only the impurity of make-up water like patent document 1, the impurity in condensate is monitored. I can't. For this reason, there is a problem that impurities resulting from this condensate are brought into the boiler and cause scale generation.

  Also, a method for monitoring the properties of the mixed water of the condensate and the makeup water may be performed. However, when monitoring the properties of the mixed water in this way, there is a problem that the detection sensitivity of impurities due to the condensate is low because the condensate is diluted with makeup water.

  An object of this invention is to provide the apparatus which monitors the mixing of the impurity to a condensate from a boiler and steam use equipment with sufficient sensitivity in view of the said prior art.

  The condensate water quality monitoring device of the present invention (Claim 1) is a device for monitoring the water quality of the condensate formed by condensing steam generated in a boiler, an air-cooled cooler for cooling the condensate, And a measuring instrument for measuring the quality of the condensate cooled by the air-cooled cooler.

  The condensate water quality monitoring apparatus according to claim 2 is the heat exchange means for exchanging heat between the condensate after the water quality is measured by the measuring instrument and the condensate introduced into the air-cooled cooler. It is characterized by having.

  The condensate quality monitoring device according to claim 3 is characterized in that, in claim 1 or 2, means for injecting a water treatment chemical into boiler feed water or boiler can water to which the condensate has been added is based on the measurement result of the measuring instrument. It is characterized by having.

  The condensate quality monitoring device according to claim 4 is the system according to any one of claims 1 to 3, wherein the condensate is not recovered as supply water to the boiler based on the measurement result of the measuring instrument. It has the means to discharge | emit to.

  The condensate water quality monitoring device according to claim 5 is characterized in that in any one of claims 1 to 4, the condensate water quality monitoring device has means for issuing an alarm based on the measurement result of the measuring instrument.

  A condensate water quality monitoring device according to a sixth aspect is characterized in that in any one of the first to fifth aspects, the condensate water quality monitoring device has a transmission means for transmitting the measurement result of the measuring instrument to the management center.

  The condensate water quality monitoring device according to claim 7 is the condensate water quality monitoring device according to any one of claims 1 to 6, wherein the measuring device is an electrical conductivity measuring device, a hardness component measuring device, an absorbance measuring device, a dissolved oxygen concentration meter, a pH meter, It is at least one of a chromaticity measuring instrument, a silica concentration measuring instrument, a chloride ion concentration measuring instrument, and an M alkalinity measuring instrument.

  In the present invention, the water quality of the condensate formed by condensing the steam generated in the boiler is monitored, so it is possible to monitor the mixing of impurities into the condensate from the boiler and the steam using equipment with high sensitivity.

  In addition, by continuously measuring the water quality of the condensate with a measuring instrument, it becomes possible to detect contamination of the condensate at an early stage.

  In the present invention, it is preferable to have heat exchange means for exchanging heat with the condensate introduced into the air-cooled cooler after the water quality is measured by the measuring instrument. Thereby, the cooling efficiency of condensate (drain) improves.

  In this invention, it is preferable to have a means to inject | pour a water treatment chemical | medical agent into the boiler feed water or boiler can water to which condensate was added based on the measurement result of a measuring device. As a result, when the water quality of the condensate deteriorates (deteriorates), it is possible to quickly start injecting water treatment chemicals or increase the amount of chemical injection, preventing the generation of scale in the boiler can. Can be suppressed.

  In the present invention, it is preferable to have means for discharging condensate out of the system based on the measurement result of the measuring instrument. Thereby, when the quality of the condensate falls, the condensate is quickly discharged out of the system and the condensate is prevented from being supplied into the boiler. As a result, scale generation in the boiler can can be prevented or suppressed.

  In the present invention, there may be a means for issuing an alarm based on the measurement result of the measuring instrument, and a transmission means for transmitting the measurement result of the measuring instrument to the management center. This ensures that the water quality deterioration of the condensate is recognized by workers and managers of the management center.

  As measuring instruments, electrical conductivity measuring instrument, hardness component measuring instrument, absorbance measuring instrument, dissolved oxygen concentration meter, pH meter, chromaticity measuring instrument, silica concentration measuring instrument, chloride ion concentration measuring instrument and M alkalinity measuring instrument At least one of these is preferably used.

  Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a system diagram of a boiler system in which a condensate water quality monitoring device according to an embodiment is installed, FIG. 2 is a system diagram of the condensate water quality monitoring device of FIG. 1, and FIG. It is a graph which shows a measurement result.

  As shown in FIG. 1, makeup water (boiler water) is supplied to the boiler 2 via the water supply pipe 1 to be steam. This steam is supplied to the steam using facility 4 through the steam pipe 3. The steam used in the steam use facility 4 is condensed into condensate, mixed with raw water in the feed water pipe 1 through the condensate pipe 5, and then supplied to the boiler 2. A water supply tank may be installed, and the condensate may be returned to the water supply tank.

  The water supply pipe 1 is connected to a pipe 8 for injecting a water treatment chemical provided with a valve 8a. A condensate water quality monitoring device 10 is connected to the condensate pipe 5 through an introduction pipe 6, and a drain pipe 7 having a valve 7a is connected thereto. The condensate pipe 5 is provided with a valve 5 a on the downstream side of the branch point of the drain pipe 7. In addition, you may provide a three-way valve in the branch part of the drainage piping 7 instead of valve 5a, 7a.

  Next, the configuration of the condensate water quality monitoring device 10 will be described.

  As shown in FIG. 2, the condensate in the condensate pipe 5 is fed to one end of the spiral metal capillary coil 14 of the air-cooled cooler 12 through the introduction pipe 6 and the heat exchanger 11 branched from the pipe 5. be introduced. The metal thin tube coil 14 is disposed in a cylindrical air cooling column 13, and a blower 15 is installed on one end side of the air cooling column 13.

  The metal capillary coil 14 preferably has an inner diameter of 0.1 to 2.0 mm, particularly 0.5 to 1.0 mm.

  In order to accurately observe the water quality of the condensate, it is preferable that the cooler 12 cools the condensate introduced into the measuring instrument 17 so that the temperature of the condensate falls within a certain range. In the present invention, since the water cooler 12 is air-cooled rather than water-cooled, it is easy to maintain the cooled condensate within the target temperature range.

  The other end of the metal thin tube coil 14 is connected to the inlet of the measuring instrument 17 through the pipe 16. The outlet of the measuring instrument 17 is connected to the cooling medium flow path 11 a of the heat exchanger 11 through the drain pipe 18.

  As the measuring instrument 17, an electrical conductivity measuring instrument, a hardness component measuring instrument, an absorbance measuring instrument, a dissolved oxygen concentration meter, a pH meter, a chromaticity measuring instrument, a silica concentration measuring instrument, a chloride ion concentration measuring instrument, and an M alkalinity measuring instrument. At least one of the vessels is preferably used.

  At the time of measurement by the measuring device 17, condensate may be introduced periodically into the measuring device 17 and measured in a batch manner. However, the condensate is constantly passed through the measuring device 17 and continuously measured. Is preferred.

  The measurement signal of the measuring instrument 17 is input to the control means 20. The control means 20 is configured to transmit a control signal to the valves 5a, 7a, 8a based on a measurement result from the measuring instrument 17, and to transmit a measurement result to a management center (not shown).

  A branch pipe 19 branches from the introduction pipe 6 in a branch shape, and the branch pipe 19 is provided with an on-off valve 19a. This on-off valve 19a is used to remove residual condensate at the start and end of the test.

  An example of the water quality monitoring method using the condensate water quality monitoring apparatus 10 configured as described above will be described.

  A part of the condensate discharged from the steam use equipment 4 through the condensate pipe 5 is taken out from the introduction pipe 6 and cooled by the heat exchanger 11 and the air-cooled cooler 12 and then introduced into the measuring instrument 17. The water quality is measured. A small amount of about 5 to 10 mL / min is sufficient for collecting the condensate (drain) into the introduction pipe 6. The measurement result is transmitted from the measuring instrument 17 to the control means 20 and from the control means 20 to a management center (not shown).

  As shown in FIG. 3, when the measured value by the measuring instrument 17 exceeds the reference value, a signal is transmitted from the control means 20 to the valves 5a, 7a, 8a and an alarm signal is transmitted to the management center. As a result, the valve 5 a is closed and the valve 7 a is opened, and the condensate discharged from the steam use facility 4 is discharged from the drain pipe 7 to the outside without being supplied to the raw water pipe 1. Moreover, the opening degree of the valve 8a increases, and the chemical injection amount of the water treatment chemical from the pipe 8 to the raw water pipe 1 is increased.

  The degree of opening of the valves 5a and 7a is controlled so as to reduce the return amount of the condensate to the raw water as the condensate water quality decreases (deteriorates). You may control to stop the return of. Further, the amount of chemical injection may be increased by increasing the opening of the valve 8a as the water quality of the condensate decreases.

  In this embodiment, since the quality of the condensate added to the makeup water is monitored, the condensate is compared with the case where the quality of the water after the condensate and the makeup water are mixed is monitored. It is possible to monitor the water quality with high sensitivity.

  Moreover, in this Embodiment, it becomes possible to detect mixing of the impurity to condensate at an early stage by measuring the quality of the condensate water continuously with the measuring instrument 17.

  In the present embodiment, condensate is discharged out of the system from the drain pipe 7 when a change occurs in the measurement value of the measuring instrument 17. Thereby, it is prevented that the impurities mixed in the condensate due to the boiler 2 and the steam using facility 4 are supplied into the boiler. As a result, scale generation in the boiler can can be prevented or suppressed.

  In the present embodiment, an alarm signal is transmitted to the management center when a change occurs in the measurement value of the measuring instrument 17, so that the contamination of the condensate is reliably recognized by the management center managers. It will be. You may make it contact the manufacturer of a water treatment chemical | medical agent or an apparatus via the internet. Note that an alarm device may be installed in the vicinity of the measuring instrument 17 so that an alarm is issued from the alarm device when the measurement value of the measurement value 17 changes. As a result, the worker in the vicinity of the measuring instrument 17 can reliably recognize the contamination of impurities in the condensate.

  In this embodiment, since the heat exchanger 11 is installed in the previous stage of the metal thin tube coil 14, the cooling efficiency of condensate (drain) is improved.

  In addition, in this Embodiment, although the injection | pouring point of a water treatment chemical | medical agent is a downstream (boiler side) rather than the connection location of the condensate piping 5 among the raw | natural water piping 1, it is not limited to this, For example, you may make it inject | pour directly into the boiler 2, and may make it inject | pour upstream from the connection location of the condensate piping 5 among the raw | natural water piping 1. FIG.

  The water quality of the condensate was monitored using the boiler system shown in FIGS. In this example, an electrical conductivity measuring instrument, an M alkalinity measuring instrument, a hardness component measuring instrument, a chloride ion concentration measuring instrument, and a silica concentration measuring instrument were installed as the measuring instrument 17.

  The steam using facility 4 is a heat exchanger that produces hot water from city water. The condensate flow rate in the introduction pipe 6 was 5 mL / min. During operation, the valve 5a was opened and the valves 7a and 8a were closed.

  FIG. 4 shows changes with time in the detected values of the measuring instruments.

  On the ninth day from the start of operation, the heat exchanger (steam use equipment 4) broke through. As is clear from FIG. 4, the condensate properties were stable up to the broken hole of the heat exchanger (steam using equipment 4), but after the broken hole, the electrical conductivity, M alkalinity, total hardness, Both chloride ion concentration and silica concentration increased greatly.

It is a systematic diagram of the boiler system provided with the condensate water quality monitoring apparatus which concerns on embodiment. It is a systematic diagram of the condensate water quality monitoring apparatus of FIG. It is a graph which shows the measurement result by a measuring device. It is a graph which shows a test result.

Explanation of symbols

2 Boiler 4 Steam Use Facility 10 Condensate Water Quality Monitoring Device 11 Heat Exchanger 13 Air Cooling Column 14 Metal Capillary Coil 15 Blower
17 Measuring instrument 20 Control means

Claims (7)

A device for monitoring the quality of the condensate water, which is formed by condensing steam generated in the boiler,
An air-cooled cooler for cooling the condensate;
A condensate water quality monitoring device comprising a measuring device for measuring the quality of the condensate water cooled by the air-cooled cooler.   The condensate water quality monitor according to claim 1, further comprising heat exchange means for exchanging heat between the condensate after the water quality is measured by the measuring instrument and the condensate introduced into the air-cooled cooler. apparatus.   3. A condensate water quality monitoring device according to claim 1 or 2, further comprising means for injecting a water treatment chemical into boiler feed water or boiler can water to which the condensate has been added based on the measurement result of the measuring instrument. . In any one of Claims 1 thru | or 3,
A condensate water quality monitoring device comprising means for discharging the condensate out of the system without collecting the condensate as supply water to the boiler based on the measurement result of the measuring instrument.   The condensate water quality monitoring device according to any one of claims 1 to 4, further comprising means for issuing an alarm based on a measurement result of the measuring instrument.   The condensate water quality monitoring device according to any one of claims 1 to 5, further comprising transmission means for transmitting a measurement result of the measuring instrument to a management center.   7. The measuring device according to claim 1, wherein the measuring device is an electrical conductivity measuring device, a hardness component measuring device, an absorbance measuring device, a dissolved oxygen concentration meter, a pH meter, a chromaticity measuring device, a silica concentration measuring device, a chloride measuring device. A condensate water quality monitoring device characterized by being at least one of a physical ion concentration measuring device and an M alkalinity measuring device.

Images