JP4406836B2 - Method and apparatus for measuring ice filling amount - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an ice filling amount measuring method and an apparatus therefor, which can directly measure the filling amount of ice in a space such as a liquid tank or a warehouse that can be sealed, and in particular, filling ice in a dynamic ice storage tank. It is suitable for measuring the amount.

  One of the cases where it is necessary to measure the filling amount of ice in the space is ice in a heat storage tank in an ice heat storage device.

  One type of this ice heat storage device is a dynamic type, which makes ice outside the heat storage tank and transports it into the tank.

 For example, supercooled water produced by a refrigerator is discharged to the upper part of the ice heat storage tank by piping, the supercooled state is released by impact etc. at the time of discharge, and it is stored in the ice heat storage tank as frozen sherbet-like ice water There is something to do.

 In addition, the supercooling water produced by the refrigerator is immediately released from the supercooling state at the supercooling release unit to form frozen sherbet-like ice water and stored in the ice heat storage tank by piping in the ice water state. is there.

  In such an ice storage tank, measuring the amount of ice filling and monitoring / controlling the amount of stored heat is an essential element for efficient operation.

For this reason, various measurement methods and apparatuses have been proposed conventionally.
For example, in the dynamic ice heat storage tank of Patent Document 1, a conductivity meter is provided to measure the conductivity of the ice slurry in the ice heat storage tank, and the remaining ice amount is calculated from the correlation between the conductivity obtained in advance and the remaining ice amount. calculate.

  In addition, in the ice filling rate measuring device of Patent Document 2, an acoustic sounding instrument installed at the bottom of the heat storage tank measures the height to the bottom of the ice slurry and the height to the top of the liquid surface without ice, and calculates the ice by calculation. The filling rate is calculated.

Furthermore, in the ice filling rate measuring device of Patent Document 3, a part of the ice slurry is diverted, heated with a heater, and the surface temperature of the heating part is measured, so that the ice filling rate is obtained from a calibration curve obtained in advance. Ask.
JP-A-8-219609 Japanese Patent Laid-Open No. 7-120018 JP 2000-179901 A

  However, each of the conventional measurement methods measures the ice filling amount indirectly from the conductivity, the ice bottom and water surface height, the surface temperature during heating, etc. There is a problem, and depending on the measurement point, there is a problem that the value is not representative of the state of the entire heat storage tank.

  In addition, it is desired to develop a method and apparatus capable of measuring not only the amount of ice in the ice storage tank but also the amount of ice stored and the amount remaining in a closed warehouse with high accuracy.

  The present invention has been made in view of the problems and demands of the prior art, and an object of the present invention is to provide an ice filling amount measuring method and apparatus for directly and accurately measuring the ice filling amount.

  In order to solve the above-described problems of the prior art, the ice filling amount measuring method according to claim 1 of the present invention is configured to supply a pressurized gas for measurement up to a set pressure in a state where the space is sealed, Understand the initial characteristics of the initial supply amount, measure the supply amount of the pressurized gas supplied up to the set pressure in the presence of ice, and fill the ice from the difference between these initial supply amount and supply amount The quantity is calculated.

  According to this ice filling amount measurement method, the initial characteristics of measuring the initial supply amount in the absence of ice by supplying the pressurized gas for measurement up to the set pressure with the space sealed, The supply amount of the pressurized gas supplied up to the set pressure in a certain state is measured, and the ice filling amount is calculated from the difference between the initial supply amount and the supply amount. Thus, the volume of ice can be determined directly from the difference in the amount of pressurized gas to be supplied until the set pressure is reached in the sealed space, and the ice filling amount can be calculated.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, the ice filling amount measuring method is characterized in that the space is sealed only at the time of measuring the supply amount, and is always open to the atmosphere. Is.

  According to this ice filling amount measuring method, the space is sealed only for a few seconds during the measurement of the supply amount, and is always kept open to the atmosphere. By measuring in a sealed state for a very short time, it is not necessary to make a completely sealed space, making it widely applicable.

  Furthermore, the ice filling amount measuring method according to claim 3 of the present invention is the structure according to claim 1 or 2, and the initial supply amount in a state where the space is a liquid tank and the liquid level is kept constant. In addition, the supply amount is measured.

  According to this ice filling amount measuring method, the space is used as a liquid tank, and the initial supply amount and the supply amount are measured in a state where the liquid level is kept constant. Even in such cases, the initial supply amount and the supply amount can always be measured under the same conditions, and the ice filling amount can be measured with high accuracy.

  According to a fourth aspect of the present invention, there is provided an ice filling amount measuring method, wherein, in addition to the configuration according to any one of the first to third aspects, the pressurized gas for measurement is compressed air or compressed nitrogen. It is what.

  According to this ice filling amount measurement method, the pressurized gas for measurement is compressed air or compressed nitrogen, which can be easily obtained and measured without adversely affecting other equipment by the pressurized gas. I am doing so.

  Furthermore, an ice filling amount measuring device according to claim 5 of the present invention is a pressurized gas supply means for supplying a pressurized gas for measurement up to a set pressure in a sealable space, and a pressurization by the pressurized gas supply means An ice filling amount is calculated from a supply amount measuring means for measuring a gas supply amount, and a difference between an initial supply amount of the pressurized gas without ice and a supply amount of the pressurized gas with ice. And a calculating means.

  According to this ice filling amount measuring apparatus, the pressurized gas for measurement is supplied up to the set pressure by the pressurized gas supply means in a state where the space is sealed, and the initial supply amount in the state without ice and the above-mentioned in the state with ice The supply amount of the pressurized gas supplied up to the set pressure is measured by the supply amount measuring means, and the ice filling amount is calculated by the calculating means from the difference between the initial supply amount and the supply amount. The volume of ice can be directly calculated from the difference in the amount of pressurized gas to be supplied until the set pressure is reached in the sealed space in the closed state and in the non-closed state, and the amount of filled ice can be calculated.

  According to a sixth aspect of the present invention, in addition to the configuration of the fifth aspect, the ice filling amount measuring device is configured to hold the liquid level of the liquid tank at a constant level while the space is constituted by a liquid tank. Means is provided.

  According to this ice filling amount measuring apparatus, the space is constituted by a liquid tank, and liquid level holding means for holding the liquid level of the liquid tank constant is provided. Even in such a case, the initial supply amount and the supply amount can always be measured under the same conditions by the liquid level holding means, and the ice filling amount can be measured with high accuracy.

  Even if deformation occurs by pressurizing the ice heat storage tank or the like, since the initial supply pressure and the measurement supply pressure are the same, the deformation amount is the same and does not affect the measurement accuracy.

  According to the ice filling amount measuring method of the first aspect of the present invention, the initial characteristic is obtained by measuring the initial supply amount in a state where there is no ice by supplying the pressurized gas for measurement up to the set pressure with the space sealed. Knowing and measuring the supply amount of the pressurized gas supplied up to the set pressure in the state of ice, and calculating the ice filling amount from the difference between these initial supply amount and supply amount, The volume of ice can be directly calculated from the difference in the supply amount of pressurized gas to be supplied until the set pressure is reached in the sealed space between the presence and absence of ice, and the ice filling amount can be calculated.

  Further, according to the ice filling amount measuring method according to claim 2 of the present invention, the space is sealed only at the time of measuring the supply amount, and is always open to the atmosphere. However, it is possible to measure the filling amount of ice by applying it in a sealed state for a very short time required for measurement, eliminating the need for a completely sealed space and applying it widely.

  Furthermore, according to the ice filling amount measuring method according to claim 3 of the present invention, the initial supply amount and the supply amount are measured while the space is used as a liquid tank and the liquid level is kept constant. Therefore, even with a dynamic ice storage tank or the like, the initial supply amount and the supply amount can always be measured under the same conditions, and the ice filling amount can be measured with high accuracy.

  According to the ice filling amount measuring method of claim 4 of the present invention, the pressurized gas for measurement is compressed air or compressed nitrogen, so that the pressurized gas can be easily obtained and pressurized. Measurement can be performed without adversely affecting other devices due to gas.

  Furthermore, according to the ice filling amount measuring apparatus of the fifth aspect of the present invention, the pressurized gas for measurement is supplied up to the set pressure by the pressurized gas supply means in a state where the space is sealed, and the initial state in which no ice is present. The supply amount and the supply amount of the pressurized gas supplied up to the set pressure with ice are measured by the supply amount measuring means, and the ice filling amount is calculated by the arithmetic means from the difference between the initial supply amount and the supply amount. As a result, the volume of ice can be determined directly from the difference in the amount of pressurized gas to be supplied until the set pressure is reached in the sealed space with and without ice. Can be calculated.

  According to the ice filling amount measuring apparatus of the sixth aspect of the present invention, the space is constituted by a liquid tank, and liquid level holding means for holding the liquid level of the liquid tank constant is provided. Even in the case of a dynamic ice storage tank or the like, the initial supply amount and the supply amount can always be measured under the same conditions by the liquid level holding means, and the ice filling amount can be measured with high accuracy.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram according to an embodiment of an ice filling amount measuring apparatus of the present invention.

  This ice filling amount measuring device 10 is used, for example, for measuring the ice filling amount of a dynamic type ice heat storage tank, and in order to pressurize the pressure in the tank to a specified value in a state where no ice is present in the heat storage tank. When you know the required amount of pressurized gas supply and want to measure the filling amount of ice, pressurize to the same pressure as when no ice is present. The volume of ice floating on the surface of the water is calculated from the difference, and the weight of the ice submerged on the surface of the water and in the water is calculated. In the case of increasing or decreasing the value, there is no change in the water surface, and the ice filling amount cannot be measured from the change in the water surface.

  Therefore, in this ice filling amount measuring device 10, the heat storage tank 11 serving as a space filled with ice is configured to be hermetically sealed, and the overflow pipe 12 and the overflow valve V1 are provided so that the amount of retained water can be kept constant. A blow pipe 13 and a blow valve V2 for providing a constant pressure inside the heat storage tank 11, for example, an atmospheric pressure state, and a blow valve V2 are provided, and the heat storage tank 11 is sealed by closing these valves V1 and V2. I can do it.

  In order to measure the filling amount of ice in the heat storage tank 11 that can be sealed, in the ice filling amount measuring device 10, a pressurized gas supply pipe 14 that supplies a pressurized gas such as compressed air or compressed nitrogen has a heat storage. A flow meter FI, a pressure gauge PI1, and a pressurized gas supply valve V3 are connected to the air layer above the tank 11, and the supply amount and supply pressure of the pressurized gas can be detected.

  Further, in this ice filling amount measuring device 10, the heat storage tank 11 is provided with thermometers TI1 to TI3 for measuring the temperature of air in the tank, and a pressure gauge PI2 for measuring the pressure in the tank.

  In addition, the heat storage tank 11 is provided with a makeup water pipe 15 and a makeup water valve V4 so that water can be replenished, and a rupture disc RD is provided, which is ruptured when the internal pressure is excessively increased. The heat storage tank 11 is protected.

  Further, in the ice filling amount measuring device 10, an arithmetic device 16 is provided as a calculating means, and the measurement results of the flow meter FI, pressure gauges PI1, PI2, thermometers TI1 to TI3 and the like are input, and the ice filling amount is calculated. And the opening / closing control of each of the valves V1 to V4 composed of electromagnetic valves and motor-operated valves.

Next, the ice filling amount measuring method will be described together with the operation of the ice filling amount measuring apparatus 10 configured as described above.
In the case of this heat storage tank 11, first, the blow valve V2 is opened to bring the inside of the tank to an atmospheric pressure state with no ice, and the overflow valve V1 is opened to make the retained water amount constant.

  In this case, when the amount of retained water is large, it is only necessary to open the overflow valve V1, but when there is no overflow from the overflow valve V1, water is replenished from the makeup water valve V4 to keep the retained water constant. It should be noted that the water stored in the heat storage tank 11 may be kept constant only at the time of measurement of at least the filling amount of ice, and does not necessarily need to be kept constant during normal heat storage operation, so long as there is no problem with heat storage. I just need it.

  Thereafter, the overflow valve V1, the blow valve V2, the make-up water valve V4, and the like are closed in order to keep the heat storage tank 11 in a sealed state.

  Then, the pressurized gas supply valve V3 is opened, compressed air, compressed nitrogen, or the like is supplied, and the air layer portion of the heat storage tank 11 is pressurized to a preset pressure, for example, 1,000 Pa. The supply amount of the pressurized gas is stored as the initial supply amount.

  After the initial supply amount is measured, the blow valve V2 is opened, and the heat storage tank 11 is opened to the atmosphere.

  After measuring the initial supply amount in a state where there is no ice in this way, the ice heat storage device is operated, and the heat storage tank 11 is stored with ice water.

  And when measuring the filling amount of ice in the heat storage tank 11 in the floating state of ice, after making the inside of the heat storage layer 11 into an atmospheric pressure state and keeping the amount of retained water constant, as in the case of no ice. The heat storage tank 11 is sealed.

  In the sealed state of the heat storage tank 11, the pressurized gas supply valve V3 is opened to supply pressurized gas such as compressed air or compressed nitrogen until the pressure becomes the same as the pressure set when there is no ice. Measure and store the amount of pressurized gas supplied up to.

  The difference between the initial supply amount without ice and the supply amount with ice thus obtained corresponds to the volume of ice floating on the water surface.

Thus, when the volume of ice floating on the water surface is obtained, the weight of the ice floating portion is obtained by calculation, and the weight of ice submerged is obtained to obtain the filling amount of all ice.
As a result, the ice filling rate IPF can be obtained.

  According to the ice filling amount measuring apparatus 10 and the method thereof, the volume of the floating ice in the heat storage tank 11 removed from the air layer can be directly measured, and the conventional indirect measurement and calibration curve are used. Compared to the case, only pressure measurement, temperature measurement, and flow rate measurement are performed, and measurement can be performed with very high accuracy, and the total weight of ice can be obtained with high accuracy from the specific gravity of water and ice.

  In addition, regardless of whether the ice is present in the heat storage tank 11, the piping, the pump, or the like, whether the ice making apparatus is stopped, in operation, or during ice melting, the heat storage tank The amount of ice filling can be reduced in a short time until the set pressure is reached by supplying pressurized gas with the same accuracy in any condition, such as waving, splashing water droplets, or entraining air into the water. Although it can be measured and depends on the size of the heat storage tank, it can be measured in a few seconds, for example.

  In addition, because it is possible to measure the amount of ice filling with high accuracy, it is possible to prevent energy loss and equipment wear due to excessive ice making, and the problem of insufficient cold heat sources due to insufficient ice making. It is possible to store heat in an optimal state.

  In addition, the ice filling amount measuring apparatus 10 and the method thereof can not only measure the total weight of ice floating in a liquid such as water as in an ice heat storage tank, but also can store and maintain the amount of ice stored in a closed warehouse or the like. It can also be applied to the measurement of the amount of ice, by measuring the initial supply amount of pressurized gas without ice and the supply amount of pressurized gas with ice until the set pressure is reached. The volume of ice can be directly measured, and the amount of ice can be determined with high accuracy.

Next, a specific calculation example of the ice filling amount measuring apparatus according to the present invention will be described.
In this calculation example, a heat storage tank having a length of 8 m, a width of 4.5 m, and a depth of 4.5 m was used, and the height of the water surface was 4 m.

(Measurement example 0)
In order to pressurize and measure the heat storage tank with air, there is a possibility that the heat storage tank expands and deforms when it is pressurized, and it is necessary to correct it.

  Table 1 shows the characteristics of the heat storage tank according to the pressure applied during measurement of the heat storage tank when the ice filling amount of the heat storage tank is “0”.

That is, when an internal pressure of 1,000 Pa is applied as the measurement pressure, the air layer in the heat storage tank is deformed, and what was 18.00 m ³ before pressurization is supplied with 0.86 kg of air. It expands to .48 m ^3, and the weight of the air in the heat storage tank is 23.26 kg before being pressurized to 24.12 kg.

(Measurement example 1)
In this measurement example 1, it is shown in Table 1 as a measurement example when the pressurized pressure of the heat storage tank is 1,000 Pa (g) and the supply amount of pressurized air at the time of ice floating is 0.83 kg. .

In this case, from the difference between the initial air supply amount in the measurement example 0 without ice and the air supply amount in the measurement example 1 in the ice floating state, the volume of the ice floating portion becomes 2.04 m ³ . The total ice volume is 25.48 m ³ , and the total ice filling amount can be calculated as 23.439 kg.
Therefore, the ice filling rate IPF in this case is 16% from the calculation result.

(Calculation Example 2)
In this calculation example 2, the pressurized pressure of the heat storage tank is set to 1,000 Pa (g), and the measurement example in the case where the supply amount of pressurized air at the time of ice floating is 0.79 kg is shown in Table 1. .

In this case, the volume of the ice floating portion is 4.78 m ³ from the difference between the initial air supply amount in the calculation example 0 without ice and the air supply amount in the measurement example 2 in the ice floating state. The total ice volume is 59.78 m ³ , and the total ice filling amount can be calculated as 54.996 kg.
Therefore, the ice filling rate IPF in this case is 38% from the calculation result.

  As described above, as shown in the measurement examples when the initial supply amount of the pressurized gas used for measurement without ice and the supply amount of the pressurized gas with ice are assumed, these supply It can be seen that by measuring the amount, the volume of ice in the floating part can be directly measured, and from these values, the total ice filling amount can be calculated to obtain the ice filling rate.

Further, in these measurement examples, when the valve diameter of the pressurized air is 20 mm and the valve diameter of the discharge air is 32 mm, the time required for pressurization at the time of measurement is 4 to 5 seconds, and the discharge after the measurement is required. The time is 55 to 59 seconds, and it can be measured in a short time and returned to the original atmosphere.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram concerning one Embodiment of the ice filling amount measuring apparatus of this invention.

Explanation of symbols

10 Ice filling amount measuring device 11 Heat storage tank (liquid tank)
12 Overflow pipe 13 Blow pipe 14 Pressurized gas supply pipe 15 Supply water pipe 16 Computation device V1 Overflow valve V2 Blow valve V3 Pressurized gas supply valve V4 Supply water valve FI Flow meter PI1, PI2 Pressure gauges TI1 to TI3 Thermometer RD Rupture Board

Claims (6)

  Supply the pressurized gas for measurement up to the set pressure with the space sealed and grasp the initial characteristics of the initial supply amount measured without ice, and supply it up to the set pressure with ice. An ice filling amount measuring method, comprising: measuring a supply amount of the pressurized gas and calculating an ice filling amount from a difference between the initial supply amount and the supply amount.   2. The ice filling amount measuring method according to claim 1, wherein the space is sealed only at the time of measuring the supply amount, and the atmosphere is always opened to the atmosphere.   3. The ice filling amount measuring method according to claim 1, wherein the space is used as a liquid tank, and the initial supply amount and the supply amount are measured in a state where the liquid level is kept constant.   The ice filling amount measuring method according to any one of claims 1 to 3, wherein the pressurized gas for measurement is compressed air or compressed nitrogen. Pressurized gas supply means for supplying pressurized gas for measurement to a settable pressure in a sealable space;
A supply amount measuring means for measuring the supply amount of the pressurized gas by the pressurized gas supply means;
An ice filling amount comprising: an arithmetic unit for calculating an ice filling amount from a difference between an initial supply amount of the pressurized gas in a state without ice and a supply amount of the pressurized gas in a state with ice Measuring device. 6. The ice filling amount measuring apparatus according to claim 5, wherein the space is constituted by a liquid tank, and liquid level holding means for holding the liquid level of the liquid tank constant is provided.

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