JP2014202458A - Boiler efficiency calculation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly accurate boiler efficiency calculation device using a new flow rate measurement device.SOLUTION: A boiler efficiency calculation device 10 includes: a feed water tank 20 having a feed water level measurement chamber 25 formed therein; a feed water amount measurement device 30 that has a feed water level measurement member 31 for measuring a first feed water level within the feed water level measurement chamber 25 and a second feed water level lower than the first feed water level and that measures feed water amount to a boiler 80 on the basis of frequency of movement between the first feed water level and the second feed water level; a blow tank 40 having a blow level measurement chamber 45 formed therein; a blow water amount measurement device 50 that has a blow level measurement member 51 for measuring a first blow level within the blow level measurement chamber 45 and a second blow level lower than the first blow level and that measures blow water amount of the boiler 80 on the basis of frequency of movement between the first blow level and the second blow level; and an efficiency calculator 75 for calculating efficiency of the boiler from the feed water amount and the blow water amount.

Description

  The present invention relates to a boiler efficiency calculation device that calculates boiler efficiency by an input / output heat method.

  In factories and buildings, steam generated in boilers is used as a heating and heating means, but due to the recent increase in interest in energy conservation, the total amount of heat generated when the fuel supplied to the boiler is completely burned. There is a growing need to understand the boiler efficiency, which is the proportion of the amount of heat used to produce steam.

  About the method of calculating the boiler efficiency of a boiler by the heat input / output method, it is disclosed by the following patent documents 1, 2, for example. Here, in order to calculate the boiler efficiency, it is necessary to measure the amount of water supplied to the boiler and the amount of blown water. In Patent Documents 1 and 2 below, the flow rate of the water supply line and the like is measured by a flow meter.

JP-A-9-119602 Japanese Patent No. 2530427

  However, the flow meter is relatively expensive, and if there is a problem with the construction method or measurement range, the measurement error of the water supply amount or blow water amount becomes large, and there is a problem that the calculation accuracy of the boiler efficiency is greatly reduced. .

  This invention is made | formed in view of such a subject, and it aims at providing the highly accurate boiler efficiency calculation apparatus using a novel flow volume measuring apparatus.

In order to solve the above problems, a boiler efficiency calculation apparatus according to the present invention is a boiler efficiency calculation apparatus that calculates boiler efficiency based on a boiler water supply amount and a blow water amount, and is installed in a water supply line of the boiler. A water supply tank in which a water supply liquid level measurement chamber is formed, and a water supply amount measurement device that is installed in the water supply tank and measures the amount of water supplied to the boiler, the first water supply liquid level in the water supply liquid level measurement chamber A feed water level measuring member that measures a second feed water level lower than the first feed water level; the first feed water level and the second feed water at a liquid level in the feed water level measurement chamber; A water supply amount measuring device for measuring the amount of water supplied to the boiler from the number of movements between them, a blow tank installed in a blow line of the boiler and having a blow liquid level measurement chamber formed therein, and the blow tank Installed in the A blow water level measuring device for measuring the amount of blow water in a blower, which measures a first blow liquid level in the blow liquid level measuring chamber and a second blow liquid level lower than the first blow liquid level. A blow water amount measuring device having a measurement member and measuring the blow water amount of the boiler from the number of movements between the first blow liquid level and the second blow liquid level of the liquid level in the blow liquid level measurement chamber;
An efficiency calculator that calculates the efficiency of the boiler from the water supply amount and the blow water amount.

  According to the boiler efficiency calculating apparatus according to the present invention, it is possible to calculate the boiler efficiency with high accuracy using a novel flow rate measuring apparatus.

FIG. 1 is a schematic diagram schematically showing the configuration of a boiler efficiency calculation apparatus according to an embodiment of the present invention. FIG. 2 is a diagram for explaining the operation when the water supply amount is measured by the water supply amount measuring device.

  Hereinafter, a boiler efficiency calculating apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram schematically showing a configuration of a boiler efficiency calculation apparatus according to the present embodiment.

  The boiler efficiency calculation device 10 is installed in the boiler 80 and shares a part of the components with the boiler 80. Here, the boiler 80 includes a can 81, a fuel supply line 85 that supplies fuel for combustion to the burner 82 of the can 81, a steam extraction line 88, a water supply line 90, a blow line 95, and a boiler 80. And a controller 70 for controlling the whole.

  The boiler efficiency calculation device 10 includes a fuel flow meter 15, a feed water tank 20, a feed water amount measuring device 30, a feed water temperature sensor 37, a blow tank 40, a blow water amount measuring device 50, a blow water temperature sensor 57, A vapor pressure sensor 60 and an efficiency calculator 75 are provided.

  The fuel flow meter 15 is a flow meter installed in the fuel supply line 85 of the boiler 80, and measures the amount of combustion fuel supplied to the burner 82.

  The water supply tank 20 is installed in the water supply line 90 of the boiler 80 and temporarily stores the water supplied to the can 81. The water supply tank 20 includes a first water supply partition 21 and a second water supply partition 22 that divide the tank into three rooms.

  Thereby, in the water supply tank 20, three rooms of the 1st water supply chamber 24, the 2nd water supply chamber 25, and the 3rd water supply chamber 26 are formed toward the downstream from the upstream of the water supply line 90. FIG. The 2nd water supply chamber 25 is a water supply liquid level measurement chamber by which a water supply liquid level is measured by the water supply liquid level measurement member 31 mentioned later.

  In addition, the water supply tank 20 is connected to the first water pipe 24 connecting the first water supply chamber 24 and the second water supply chamber 25 and the second water supply chamber 25 connecting the second water supply chamber 25 and the third water supply chamber 26. Two communication pipes 28 are provided, and the water supply can move between the water supply chambers through the communication pipes 27 and 28. Here, the first communication pipe 27 is a water supply inflow path of the second water supply chamber 25 that is a water supply liquid level measurement chamber, and the second communication pipe 28 is a water supply outflow path of the second water supply chamber 25.

  The water supply tank 20 includes a first on-off valve 271 installed in the first series communication pipe 27 and a second on-off valve 281 installed in the second communication pipe 28. The first on-off valve 271 is provided in the first series communication pipe 27. The pipe 27 is opened and closed, and the second on-off valve 281 opens and closes the second communication pipe 28. That is, the first on-off valve 271 is a water supply inflow path opening / closing member of the second water supply chamber 25, and the second on-off valve 281 is a water supply outflow path opening / closing member of the second water supply chamber 25.

  The water supply amount measuring device 30 is installed in the water supply tank 20 and has a function of measuring the amount of water supply from the water supply tank 20 to the can 81. The water supply amount measuring device 30 includes a water supply liquid level measuring member 31 that measures the liquid level in the second water supply chamber 25, and a water supply amount calculator 35 that calculates the water supply amount from the measured value of the water supply liquid level measuring member 31. ing. The water supply amount calculator 35 is configured integrally with the controller 70 of the boiler 80.

  The feed water level measuring member 31 includes a first feed water level electrode 311 and a second feed water level electrode 312 that extend vertically in the second feed chamber 25. The first water supply liquid level electrode 311 is an electrode for detecting a predetermined first liquid level in the second water supply chamber 25, and the second water supply liquid level electrode 312 is lower than the first liquid level. It is an electrode for detecting a predetermined second liquid level. Therefore, the second water supply liquid level electrode 312 is longer than the first water supply liquid level electrode 311, and the lower end thereof is positioned lower.

  The water supply amount calculator 35 obtains the number of times that the water supply liquid level in the second water supply chamber 25 has moved from the first liquid level to the second liquid level by the detection of the water supply liquid level measuring member 31, and from this number of liquid level movements The amount of water supplied from the water supply tank 20 to the boiler 80 is calculated, and the opening / closing of the first on-off valve 271 and the second on-off valve 281 is controlled in measuring the amount of water supply.

  Specifically, the water supply amount calculator 35, in measuring the water supply amount, includes a first on-off valve 271 that is a water supply inflow path opening / closing member of the second water supply chamber 25 and a second on-off valve 281 that is a water supply outflow path opening / closing member. So that the water supply liquid level in the second water supply chamber 25 is lowered from the first liquid level to the second liquid level, the first on-off valve 271 is always closed. The second on-off valve 281 is opened, and the first on-off valve 271 is always opened with the second on-off valve 281 closed while the feed water level is rising from the second liquid level to the first liquid level. Control to keep.

  Thus, while the water level in the second water supply chamber 25 is descending from the first liquid level to the second liquid level, there is no new inflow into the second water supply chamber 25, and the liquid level reaches the second liquid level. When the position is lowered, the water supply has moved from the second water supply chamber 25 to the third water supply chamber 26 by the amount of water existing between the first liquid level and the second liquid level in the second water supply chamber 25. This movement amount corresponds to the amount of water supplied from the water supply tank 20 to the boiler 80.

  Therefore, by setting a constant volume between the first liquid level and the second liquid level in the second water supply chamber 25 in the water supply amount calculator 35 in advance, the water supply amount calculator 35 is set to the second water supply chamber 25. The volume flow rate of the feed water to the boiler 80 can be calculated from the number of movements from the first liquid level to the second liquid level (the number of constant volume changes).

  Water supply from the outside to the water supply tank 20 is performed by, for example, a ball tap or the like so that the liquid level in the first water supply chamber 24 of the water supply tank 20 becomes a predetermined liquid level. Water supply from the chamber 26 to the boiler 80 is appropriately performed according to the boiler load in the boiler 80 and the like. Therefore, since the inflow and the outflow are performed at the same time when viewed from the entire water supply tank 20, it is difficult to calculate the volume flow rate of the water supplied through the water supply tank 20 due to the fluctuation of the liquid level in the water supply tank 20.

  On the other hand, by dividing the inside of the water supply tank 20 into the three water supply chambers 24, 25, and 26 as in the present embodiment, the second water supply chamber can be appropriately inflow and outflow simultaneously. In 25, control was performed so that inflow and outflow into the room would not be performed simultaneously, and calculation of the amount of water supply due to liquid level fluctuations was made possible.

  FIG. 2 is a diagram for explaining the operation when the water supply amount is measured by the water supply amount measuring device 30. The water supply liquid level in the second water supply chamber 25, the first on-off valve 271 and the second on-off valve 281 are shown. It is a figure which shows the relationship at the time of water supply amount measurement of the open / close state of this and the frequency | count of the movement of the liquid level which the water supply amount calculator 35 counts. As shown in the figure, first, the water supply amount calculator 35 sets the number of movements to zero when the water supply liquid level reaches the first liquid level, closes the first on-off valve 271, and closes the second on-off valve 281. Is in an open state.

  Then, since the liquid level of the 2nd water supply chamber 25 and the 3rd water supply chamber 26 which are connected by the 2nd communicating pipe 28 becomes the same, the liquid level in the 3rd water supply chamber 26 is accompanied with the water supply to the boiler 80. If it falls gradually, the liquid level in the 2nd water supply chamber 25 will also fall together. At this time, since the first on-off valve 271 is closed, water does not move from the first water supply chamber 24 into the second water supply chamber 25.

  When the water supply liquid level in the second water supply chamber 25 decreases to the second liquid level as the water is supplied to the boiler 80, the water supply amount calculator 35 counts the number of times the liquid level moves from the first liquid level to the second liquid level. Is counted once, and the first on-off valve 271 is opened and the second on-off valve 281 is closed.

  If it does so, between the 2nd water supply chamber 25 and the 3rd water supply chamber 26 will be interrupted | blocked, and the liquid level of the 2nd water supply chamber 25 will be the same as the liquid level of the 1st water supply chamber 24 connected by the 1st continuous pipe 27. Become. When the liquid level in the first water supply chamber 24 decreases due to the movement of the water supply to the second water supply chamber 25, water is supplied into the first water supply chamber 24 sequentially from the upstream portion (supply water line) of the water supply line 90. The liquid level in the second water supply chamber 25 that has decreased to the liquid level gradually rises to the first liquid level by the water supply from the first water supply chamber 24.

  When the water supply liquid level in the second water supply chamber 25 rises to the first liquid level, the water supply amount calculator 35 again controls the first open / close valve 271 and the second open / close valve 281 to be opened. Thereby, the inflow from the first water supply chamber 24 into the second water supply chamber 25 is stopped, and the outflow from the second water supply chamber 25 to the third water supply chamber 26 is resumed. And if the liquid level in the 2nd water supply chamber 25 falls to a 2nd liquid level again, the water supply amount calculator 35 will count the frequency | count of a movement twice.

  By repeating such control, the water supply amount calculator 35 obtains the number of movements of the liquid level in the second water supply chamber 25 from the first liquid level to the second liquid level, and based on this number of movements, the water supply The amount of water supplied from the tank 20 to the boiler 80 is calculated.

  Note that the amount of water supply is not calculated by calculating the outflow amount from the second water supply chamber 25 based on the number of times of movement from the first liquid level to the second liquid level, but from the second liquid level to the first liquid level. The amount of water supplied may be obtained by calculating the amount of inflow into the second water supply chamber 25 based on the number of times of movement.

  The water supply temperature sensor 37 is installed in the water supply tank 20 and measures the water temperature in the second water supply chamber 25.

  The blow tank 40 is installed in the blow line 95 of the boiler 80 and temporarily stores blow water from the can 81. The blow tank 40 includes a first blow partition 41 that partitions the inside of the tank into two rooms.

  As a result, two chambers, a first blow chamber 44 and a second blow chamber 45, are formed in the blow tank 40 from the upstream side to the downstream side of the blow line 95. The second blow chamber 45 is a blow liquid level measurement chamber in which the blow liquid level is measured by a blow liquid level measurement member 51 described later.

  The blow tank 40 also includes a first series pipe 47 that connects the first blow chamber 44 and the second blow chamber 45, and the blow water passes between the blow chambers through the first series pipe 47. Move. The first series pipe 47 is a blow inflow path of the second blow chamber 45 which is a blow liquid level measurement chamber, and a blow line 95 connected to the outlet of the blow tank 40 is a blow out path of the second blow chamber 45. is there.

  The blow tank 40 includes a first on-off valve 471 installed on the first series pipe 47 and a second on-off valve 481 installed on the blow line 95 which is a blow out path. The series passage 47 is opened and closed, and the second on-off valve 481 opens and closes a blow line 95 that is a blow out path. That is, the first opening / closing valve 481 is a blow inflow path opening / closing member of the second blow chamber 45, and the second opening / closing valve 481 is a blow outflow path opening / closing member of the second blow chamber 45.

  The blow water amount measuring device 50 is installed in the blow tank 40 and has a function of measuring the blow water amount discharged from the can 81. The blow water amount measuring device 50 includes a blow liquid level measuring member 51 that measures the liquid level in the second blow chamber 45, and a blow water amount calculator 55 that calculates the blow water amount from the measurement value of the blow liquid level measuring member 51. ing. The blow water amount calculator 55 is configured integrally with the controller 70 of the boiler 80.

  The blow liquid level measuring member 51 includes a first blow liquid level electrode 511 and a second blow liquid level electrode 512 that extend vertically in the second blow chamber 45. The first blow liquid level electrode 511 is an electrode for detecting a predetermined first liquid level in the second blow chamber 45, and the second blow liquid level electrode 512 is lower than the first liquid level. It is an electrode for detecting a predetermined second liquid level. Therefore, the second blow liquid level electrode 512 is longer than the first blow liquid level electrode 511, and the lower end thereof is positioned at a low level.

  The blow water amount calculator 55 obtains the number of times the blow liquid level in the second blow chamber 45 has moved from the first liquid level to the second liquid level by detection of the blow liquid level measuring member 51, and from this number of liquid level movements While calculating the blow water amount of the boiler 80, the opening / closing of the first on-off valve 471 and the second on-off valve 481 is controlled in measuring the blow water amount.

  Specifically, the blow water amount calculator 55 determines the blow water amount by measuring the first on-off valve 471 that is a blow inflow path opening / closing member of the second blow chamber 45 and the second on-off valve 481 that is a blow out path opening / closing member. So that the first open / close valve 471 is always closed while the blow liquid level in the second blow chamber 45 is descending from the first liquid level to the second liquid level. The second on-off valve 481 is opened, and the first on-off valve 471 is always opened while the second on-off valve 481 is closed while the blow liquid level is rising from the second liquid level to the first liquid level. Control to keep.

  As a result, while the liquid level in the second blow chamber 45 is descending from the first liquid level to the second liquid level, there is no new inflow into the second blow chamber 45. When the liquid level drops from the liquid level to the second liquid level, the amount of water existing between the first liquid level and the second liquid level in the second blow chamber 45 is discharged from the second blow chamber 45 to the outside. It becomes the amount of drainage.

  Therefore, by setting a constant volume between the first liquid level and the second liquid level in the second blow chamber 45 in the blow water amount calculator 55 in advance, the blow water amount calculator 55 is connected to the second blow chamber 45. Based on the number of times of movement from the first liquid level to the second liquid level, the volume flow rate of blow water discharged from the boiler 80 can be calculated.

  Since the inflow of the blow water from the boiler 80 to the blow tank 40 is performed at a predetermined timing, if the inflow to the blow tank 40 is performed while the blow water is being discharged from the blow tank 40, the blow tank It is difficult to calculate the volume flow rate of the blow water that has passed through the blow tank 40 due to the fluctuation of the liquid level in the 40.

  On the other hand, by dividing the inside of the blow tank 40 into two blow chambers 44 and 45 as in this embodiment, while the drainage of the boiler 80 is performed at an arbitrary timing, Control was made so that inflow and outflow into the room do not occur at the same time, making it possible to calculate the amount of blown water due to liquid level fluctuations.

  When the blow water amount is measured by the blow water amount measuring device 50, the same control process as that of the water supply amount measuring device 30 is performed on the first on-off valve 471 and the second on-off valve 481 as shown in FIG. The blow water amount calculator 55 obtains the number of movements from the first liquid level to the second liquid level in the second blow chamber 45, and can calculate the amount of blow water from the boiler 80 based on the number of movements. .

  In the blow water amount measuring device 50, the second liquid is not calculated by calculating the outflow amount from the second blow chamber 45 based on the number of times of movement from the first liquid level to the second liquid level. The inflow amount into the second blow chamber 45 may be calculated based on the number of times of movement from the first to the first liquid level to obtain the blow water amount.

  The blow water temperature sensor 57 is installed in the blow tank 40 and measures the water temperature in the second blow chamber 45. The vapor pressure sensor 60 is installed in the can body 81 and measures the pressure of the vapor generated by the boiler 80.

  The efficiency calculator 75 includes a fuel supply amount to the boiler 80 measured by the fuel flow meter 15, a water supply amount to the boiler 80 measured by the water supply amount measuring device 30, a blow water amount of the boiler 80 measured by the blow water amount measuring device 50, The boiler efficiency is calculated based on the feed water temperature measured by the feed water temperature sensor 37, the blow water temperature measured by the blow water temperature sensor 57, and the vapor pressure measured by the vapor pressure sensor 60. The efficiency calculator 75 is configured integrally with the controller 70 of the boiler 80.

Specifically, since the following relational expression (input / output heat method) is established with respect to the boiler efficiency, the efficiency calculator 75 calculates the boiler efficiency based on the third stage (Expression 1) of the following relational expression.

  Here, the “water supply amount” uses the measurement value of the water supply amount measurement device 30, and the “blow water amount” uses the measurement value of the blow water amount measurement device 50. “Water supply density” is obtained from the measured value of the feed water temperature sensor 37, and “Blow water density” is obtained from the measured value of the blow water temperature sensor 57.

  “Steam heat quantity” is obtained from the measured value of the vapor pressure sensor 60, but the average value is used because the steam pressure varies somewhat during the measurement period. “Feed water heat amount” is obtained from the measured value of the feed water temperature sensor 37. As the “combustion amount”, the measured value of the fuel flow meter 15 is used. The “low fuel heating value” is a value determined by the type of fuel.

  As described above, the boiler efficiency calculation device 10 has been described in detail. In the present embodiment, the water supply is performed from the fluctuation of the liquid level in the water supply tank 20 or the blow tank 40 without installing a flow meter in the water supply line 90 or the blow line 95. The amount of water and the amount of blow water are measured, and the amount of water supply and the amount of blow water can be accurately measured at low cost, and the boiler efficiency can be calculated with high accuracy.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the number of rooms in the tank used for measuring the flow rate can be changed as appropriate, and one room may be used as long as a room that does not flow into and out of the room at the same time can be configured.

  In the above embodiment, a fuel flow meter is used to measure the amount of fuel supplied. However, when the fuel is liquid fuel, the water supply amount measuring device and the blow water amount measuring device of the above embodiment are used. The fuel supply amount may be measured based on the fluctuation of the liquid level in the tank installed in the fuel supply line.

DESCRIPTION OF SYMBOLS 10 Boiler efficiency calculation apparatus 15 Fuel flow meter 20 Water supply tank 21 1st water supply partition 22 2nd water supply partition 24 1st water supply chamber 25 2nd water supply chamber 26 3rd water supply chamber 27 1st continuous pipe 271 1st on-off valve 28 1st Double communication rod 281 Second on-off valve 30 Water supply amount measuring device 31 Water supply liquid level measuring member 311 First water supply liquid level electrode 312 Second water supply liquid level electrode 35 Water supply amount calculator 37 Water supply temperature sensor 40 Blow tank 41 First Blow partition 44 First blow chamber 45 Second blow chamber 47 First series pipe 471 First on-off valve 481 Second on-off valve 50 Blow water amount measuring device 51 Blow liquid level measuring member 511 First blow liquid level electrode 512 Second Blow liquid level electrode 55 Blow water amount calculator 57 Blow water temperature sensor 60 Vapor pressure sensor 70 Controller 75 Efficiency calculator 80 Boiler 81 Can body 2 burner 85 fuel supply line 88 steam extraction line 90 water supply line 95 blowline

Claims (3)

In the boiler efficiency calculation device that calculates the boiler efficiency based on the amount of water supplied and the amount of blow water in the boiler,
A water supply tank installed in the boiler water supply line, in which a water supply liquid level measurement chamber is formed;
A water supply amount measuring device that is installed in the water supply tank and measures the amount of water supplied to the boiler, the first water supply liquid level in the water supply liquid level measurement chamber and the second water supply lower than the first water supply liquid level A feed water level measuring member for measuring the liquid level, and water supply to the boiler from the number of movements between the first feed water level and the second feed water level of the liquid level in the feed water level measurement chamber A water supply measuring device for measuring the amount,
A blow tank installed in the blow line of the boiler, in which a blow liquid level measurement chamber is formed;
A blow water amount measuring device that is installed in the blow tank and measures the blow water amount of the boiler, the first blow liquid level in the blow liquid level measuring chamber and the second blow liquid lower than the first blow liquid level A blow liquid level measuring member for measuring the level of the boiler, and the amount of blow water in the boiler is determined from the number of movements between the first blow liquid level and the second blow liquid level of the liquid level in the blow liquid level measurement chamber. A blow water volume measuring device to measure,
An efficiency calculator for calculating the efficiency of the boiler from the water supply amount and the blow water amount;
A boiler efficiency calculating device comprising:   2. The boiler efficiency calculating apparatus according to claim 1, wherein the feed water tank is partitioned into at least three rooms connected in series, and the feed water level measuring chamber is an intermediate room. The water supply tank includes a water supply inflow path opening / closing member installed in an inflow path of the water supply liquid level measurement chamber, and a water supply outflow path opening / closing member installed in an outflow path of the water supply liquid level measurement chamber,
The water supply amount measuring device is configured to provide a water supply inflow path opening / closing member of the water supply liquid level measurement chamber while the liquid level in the water supply liquid level measurement chamber is lowered from the first water supply liquid level to the second water supply liquid level. And while the liquid level in the feed water level measurement chamber rises from the second feed water level to the first feed water level, the feed water outflow path opening / closing member of the feed water level measurement chamber is Control to keep it closed,
The blow tank includes a blow inflow path opening / closing member installed in an inflow path of the blow liquid level measurement chamber, and a blow outflow path opening / closing member installed in an outflow path of the blow liquid level measurement chamber,
The blow water amount measuring device is configured to open and close the blow inflow path of the blow liquid level measuring chamber while the liquid level in the blow liquid level measuring chamber is lowered from the first blow liquid level to the second blow liquid level. Is closed, and while the liquid level in the blow liquid level measurement chamber is rising from the second blow liquid level to the first blow liquid level, the blow outflow path opening / closing member of the blow liquid level measurement chamber is Control to keep it closed,
The boiler efficiency calculation apparatus according to claim 1 or 2, characterized by the above-mentioned.

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