JP5559709B2 - Volatilization measuring apparatus and method - Google Patents

Description

  The present invention relates to an apparatus and a method for measuring the volatilization amount of a narrow tube effluent.

  Conventionally, in order to calibrate a medium-sized flow meter and a large-sized flow meter used in chemical plants and steel plants, there are liquid flow rate calibration facilities of medium flow rate and large flow rate, respectively.

  An outline of a conventional liquid flow rate calibration facility will be described. FIG. 8 is a diagram showing an outline of a conventional liquid flow rate calibration facility. FIG. 9 is a diagram illustrating a conventional nozzle. In FIG. 8, the liquid flow rate calibration facility guides the liquid from the test liquid tank 906 in which the liquid is stored to the test pipe line 908, and generates a stable flow in the test pipe line 908. The generated stable flow passes through the flow meter 905 provided in the test pipe 908 and flows into the weighing container 907 via the diverter 901 provided between the sample nozzle 902 and the weighing container 907. Thereafter, the liquid flow rate calibration facility switches the flow at a high speed by the diverter 901 after a predetermined time (inflow time) has elapsed, and stops the flow of the liquid into the weighing container 907. Then, the liquid flow rate calibration facility obtains the flow rate of the liquid per unit time from the inflow amount and the inflow time of the liquid that has flowed into the weighing container 907, and the flow rate is calculated based on the obtained flow rate and the flow rate measured by the flow meter 905. Calibrate the total 905. Further, as shown in FIG. 9, in the case of a small flow rate, a needle 921 is attached to the center of the tube of the sample nozzle 902 and used in order to create a stable flow.

  In such a calibration device for the flow meter 905, in order to perform high-precision calibration of the flow meter 905 in a small flow rate region, it is necessary to make the liquid flowing out of the sample nozzle 902 and flowing into the weighing container 907 into a continuous flow. In the case of continuous flow, liquid volatilization occurs before the flow enters the weighing container 907. Therefore, it is necessary to accurately measure how much the liquid flowing out from the sample nozzle 902 and flowing into the weighing container 907 evaporates before flowing into the weighing container 907.

  For example, Patent Document 1 that discloses a technique for estimating fuel dilution of engine oil is known. The dilution monitoring computer disclosed in Japanese Patent Laid-Open No. 2004-228561 each time the regeneration control of the exhaust purification device by the post-injection of fuel is executed, the new amount of fuel mixed into the engine oil during the regeneration control execution period, and the previous time of regeneration control And the volatilization amount of the fuel from the engine oil in the regeneration interval from the execution to the current execution. Then, the difference between the calculated new mixing amount and the volatilization amount is integrated every time the regeneration control is executed to calculate the fuel mixing amount in the engine oil.

JP 2006-9597 A

  However, the technique disclosed in Patent Document 1 is not a technique for measuring a volatilization amount of a liquid flow rate in a small flow rate region that flows out from a nozzle and flows into a weighing container. If the volatilization amount of the liquid in the small flow rate region can be measured in advance, the measured volatilization amount is used as a correction value, and the flow meter is accurately calibrated in the small flow rate region without being affected by the volatilization amount. be able to.

  Therefore, there is a need for an apparatus that accurately measures the volatilization amount of a liquid in a small flow rate region that flows out from a nozzle and flows into a weighing container.

  It is an object of the present invention to provide a volatilization amount measuring apparatus and method for accurately measuring the volatilization amount of a liquid in a small flow rate region that flows out from a nozzle and flows into a weighing container.

  The present invention provides the following solutions.

  (1) A nozzle for discharging liquid, a weighing container for storing the liquid flowing out from the nozzle, and a weighing meter for measuring the weight of the liquid flowing into the weighing container, and the liquid flowing out from the nozzle is measured by the weighing A volatilization amount measuring apparatus for measuring a volatilization amount until it accumulates in a container, wherein a thin tube nozzle that forms a laminar continuous flow when the flow rate is smaller than a certain value at the tip of the nozzle, and a tip of the thin tube nozzle And a distance changing means for changing a relative distance between the weighing container and a bottom of the weighing container, and a control means for controlling the change of the distance by the distance changing means, the control means from the capillary tube to the weighing Measuring means for measuring the weight of the liquid flowing into the container by the weighing instrument; first measuring means for performing a first measurement by the measuring means; and changing the distance, and a second measuring means by the measuring means. A second measuring means for performing constant, said the weight measured by the first measuring means further comprises a calculating means for calculating the weight was measured, the difference of the said second measuring means, volatilization amount measuring device.

  According to the configuration of (1), the volatilization amount measuring apparatus according to the present invention includes a thin tube nozzle that forms a laminar continuous flow when the flow rate is smaller than a certain value, and a tip of the thin tube nozzle. Distance changing means for changing the relative distance from the bottom of the weighing container, and control means for controlling the change of the distance by the distance changing means are provided. The volatilization amount measuring device has a measuring means for measuring the weight of the liquid flowing into the weighing container from the thin tube nozzle by a weighing meter, performs the first measurement by the measuring means, and the tip of the thin tube nozzle and the bottom of the weighing container. And the second measurement is performed by the measuring means, and the difference between the weight measured by the first measurement and the weight measured by the second measurement is calculated.

  That is, the volatilization amount measuring device forms a laminar continuous flow by the thin tube nozzle, ensures a constant flow rate of the flow rate flowing into the weighing container, and determines the weight of the liquid flowing into the weighing vessel from the tip of the thin tube nozzle. Measure by changing the distance to the bottom of the weighing container. Therefore, the volatilization amount measuring apparatus according to the present invention can accurately measure the volatilization amount of the liquid in the small flow rate region that flows out from the nozzle and flows into the weighing container.

(2) a nozzle for discharging liquid, a weighing container for storing the liquid flowing out from the nozzle, and a weighing meter for measuring the weight of the liquid flowing into the weighing container, and the liquid flowing out from the nozzle is measured by the weighing It is a method executed by a volatilization amount measuring device that measures the volatilization amount until it accumulates in a container,
The volatilization amount measuring device includes a capillary tube nozzle that forms a laminar continuous flow when the flow rate is smaller than a certain value, and a relative relationship between the tip of the capillary tube nozzle and the bottom of the weighing container. A distance changing means for changing the distance; and a control means for controlling the change of the distance by the distance changing means, wherein the control means measures the weight of the liquid flowing into the weighing container from the capillary tube nozzle. Having measuring means to measure by
The method includes a first measurement step in which the control means measures with the measurement means, a change step in which the control means changes the distance, and a second measurement step in which the control means measures with the measurement means. And a calculation step of calculating a difference between the weight measured by the first measurement step and the weight measured by the second measurement step.

  Therefore, the method according to the present invention can accurately measure the volatilization amount of the liquid in the small flow rate region that flows out from the nozzle and flows into the weighing container, as in (1).

  ADVANTAGE OF THE INVENTION According to this invention, the volatilization amount of the liquid in the small flow area which flows out out of a nozzle and flows in into a weighing container can be measured accurately. As a result, the present invention can provide a correction value for the volatilization amount so that the flow meter can be accurately calibrated in a small flow rate region without being affected by the volatilization amount.

It is a schematic diagram which shows the outline | summary of the volatilization amount measuring apparatus which is one Embodiment of this invention. It is a figure which shows an example of the thin tube nozzle which concerns on one Embodiment of this invention. It is a figure which shows an example of the hardware constitutions of the control part in the volatilization amount measuring apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows the processing content of the control part in the volatilization amount measuring apparatus which concerns on one Embodiment of this invention. It is a figure which shows the measurement of the volatilization amount in the volatilization amount measuring apparatus which concerns on one Embodiment of this invention. It is a figure which shows the measurement of the volatilization amount by changing distance in the volatilization amount measuring apparatus which concerns on one Embodiment of this invention. It is a figure which shows estimation of the volatilization amount in the volatilization amount measuring apparatus which concerns on one Embodiment of this invention. It is a figure which shows the outline | summary of the conventional liquid flow volume calibration equipment. It is a figure explaining the conventional nozzle.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing an outline of a volatilization amount measuring apparatus 10 according to an embodiment of the present invention. The volatilization amount measuring apparatus 10 is installed at a tip of the test liquid tank 504 for storing liquid, a pipe line 505 connected to the test liquid tank 504, a nozzle 200 through which the liquid flowing through the pipe line 505 flows out, and the nozzle 200. A thin tube nozzle 201, a weighing container 300 for storing liquid flowing out from the thin tube nozzle 201, a moving device 301 as a distance changing means for changing the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300, and weighing A weigher 400 that measures the weight of the liquid that has flowed into the container 300, and measures the volatilization amount until the liquid that flows out of the thin tube nozzle 201 accumulates in the weighing container 300.

  In FIG. 1, the liquid is guided to the pipe line 505 from the test liquid tank 504 in which the liquid is stored. In the pipe 505, a constant pressure is formed before the narrow tube nozzle 201 by the pressure adjustment valve 502 and the liquid amount adjustment valve 501.

  The liquid with a constant pressure formed by the pressure adjustment valve 502 and the liquid amount adjustment valve 501 flows out from the narrow tube nozzle 201 installed at the tip of the nozzle 200. The flow flowing out of the thin tube nozzle 201 does not become a dripping state as shown in FIG. 9 of the prior art, but forms a continuous laminar flow 95 (see FIG. 2 described later).

  The laminar flow 95 is a rotating paraboloid in which the liquid flow velocity distribution has the center of the narrow tube nozzle 201 as the rotation axis, and is a steady flow that does not include irregular fluctuations such as vortices. Specifically, a laminar flow 95 is formed by the tube inner diameter, length, liquid flow velocity, density, and viscosity of the thin tube nozzle 201 through which the liquid flows. In the laminar flow 95, if the fluid is the same and the differential pressure across the narrow tube is constant, the flow rate flowing through the tube is determined.

  The weight of the liquid flowing into the weighing container 300 is measured by the weighing meter 400. The weighing scale 400 transmits the measured weight value to the control unit 410.

The moving device 301 (for example, a lifting platform) moves the weighing container 300 up and down and changes the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300.
In addition, a device that is installed in the nozzle 200 and moves the position of the tip of the thin tube nozzle 201 (for example, a device that changes the position of the nozzle 200) is a relative relationship between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300. The distance may be changed. Alternatively, the moving device 301 may be installed under the weighing scale 400, and the weighing scale 400 may be moved up and down to change the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300.

The control unit 410 controls the change of the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300 by the moving device 301.
Specifically, the control unit 410 causes the moving device 301 to position the tip of the thin tube nozzle 201 near the bottom of the weighing container 300. Next, the control unit 410 continuously receives and stores the weight of the liquid flowing into the weighing container 300 every predetermined time for a predetermined time (referred to as a first measurement).
Next, the control unit 410 changes the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300 using the moving device 301, for example, when using a diverter (not shown). The distance between the top of the weighing container and the bottom of the weighing container 300 is set.
Next, similarly, the control unit 410 continuously receives and stores the weight of the liquid flowing into the weighing container 300 every predetermined time for a predetermined time (referred to as second measurement).
Then, the control unit 410 calculates the difference between the weight by the first measurement and the weight by the second measurement, and estimates the volatilization amount.

  Specifically, the control unit 410 calculates a relational expression (for example, a linear expression by the least square method) between a predetermined time (measurement time) and the weight based on the weight for each predetermined time stored in the first measurement. . Similarly, the control unit 410 calculates a relational expression (for example, a linear expression by the least square method) between a predetermined time (measurement time) and the weight based on the weight for each predetermined time stored in the second measurement. Then, the volatilization amount is calculated from the difference between the calculated relational expressions (for example, the difference between the linear expressions).

It is assumed that dynamic verification is performed in advance on an electronic balance (not shown) used for the weighing scale 400. Usually, the measurement with an electronic balance is a static measurement, so the calibration is a static calibration with a weight. However, the measurement of the volatilization amount of the liquid flowing out from the narrow tube nozzle requires dynamic calibration of the reference electronic balance. In particular, the correction of the volatilization amount of the liquid flowing out from the thin tube nozzle is necessary for calibration of the flow meter at a small flow rate. Therefore, the method will be described only for dynamic calibration of the electronic balance at a small flow rate.
The dynamic calibration of the electronic balance at a small flow rate is performed according to the following procedures (1) to (4).
(1) A liquid with a negligible volatilization amount, and a constant flow rate is created by a laminar flow by the thin tube nozzle 201.
(2) Perform static confirmation of the electronic balance. That is, the weight before the start of inflow into the weighing container 300 and the weight at the sample time t are measured after flowing into the weighing container 300 with a diverter, and the sample weight is calculated from the difference.
(3) Record the continuous data and read timing time of the electronic balance after the start of the flow into the weighing container 300, and confirm the weight during the sample time t from the result.
(4) The dynamic accuracy of the electronic balance is evaluated from the values of (2) and (3). The value of (3) may be the case where the measured value is used as it is as the weight, or the value obtained from the equation obtained from the measured value by the least squares method as the weight.

  FIG. 2 is a diagram illustrating an example of a thin tube nozzle 201 according to an embodiment of the present invention. For example, by using a tube having an inner diameter of φ0.08 to φ0.3 as the thin tube nozzle 201, the thin tube nozzle 201 forms a continuous laminar flow 95 even when the flow rate is a small flow rate smaller than a certain value. Can do. For example, when a liquid having a liquid viscosity of 0.00077 [Pa · s] is flowed in a continuous flow with a flow rate of 0.3 L / h, a laminar flow 95 is realized with a capillary inner diameter of 0.15 mm, a length of 15 mm, and a front-back differential pressure of 100 kPa. be able to. A constant flow rate can be realized by the thin tube nozzle 201 configured as described above.

  FIG. 3 is a diagram illustrating an example of a hardware configuration of the control unit 410 in the volatilization amount measuring apparatus 10 according to an embodiment of the present invention. The control unit 410 includes a CPU (Central Processing Unit) 1010, a bus line 1005, a communication I / F 1040, a main memory 1050, a BIOS (Basic Input Output System) 1060, an I / O controller 1070, a keyboard / mouse 1100, a display 1022, and An input / output I / F device / moving device controller 2000 is provided.

  The BIOS 1060 stores a boot program executed by the CPU 1010 when the control unit 410 is activated, a program depending on the hardware of the control unit 410, and the like.

  Storage means such as a hard disk 1074 and a semiconductor memory 1078 can be connected to the I / O controller 1070.

  The hard disk 1074 stores a program for the control unit 410 to execute the function of the present invention, and further stores the calculated volatilization amount, the received measurement value, and the like, and can constitute various databases.

  The program provided to the control unit 410 is provided by being stored in a recording medium such as the hard disk 1074 or a memory card. This program may be installed in the control unit 410 and executed by being read from the recording medium via the I / O controller 1070 or downloaded via the communication I / F 1040.

  The above-described program may be provided to the control unit 410 via a communication line using a storage device such as a hard disk or an optical disk library provided in a server system connected to a dedicated communication line as a recording medium.

  Here, the display unit 1022 displays the calculation processing result by the control unit 410, for example, the calculated volatilization amount, the received measurement value, and the like, and displays a display device such as a cathode ray tube display device or a liquid crystal display device. Including.

  The communication I / F 1040 is a network adapter for enabling the control unit 410 to be connected to a terminal or the like via a dedicated network.

  The input / output I / F device / moving device controller 2000 is a device including an I / F device that connects the control unit 410, the moving device 301 and the weighing meter 400, and a moving device controller that controls the moving device 301. The control unit 410 outputs a movement control signal to the moving device 301 via the input / output I / F device / moving device controller 2000 and receives the weight from the weighing scale 400.

  FIG. 4 is a flowchart showing the processing contents of the control unit 410 in the volatilization amount measuring apparatus 10 according to an embodiment of the present invention.

  In step S <b> 101, the CPU 1010 receives the weight as the measurement value from the weighing meter 400 every predetermined time (for example, every second), and stores the received weight.

  In step S102, the CPU 1010 determines whether or not a certain time has elapsed. If this determination is YES, the CPU 1010 moves the process to step S103, and if NO, the CPU 1010 moves the process to step S101.

  In step S <b> 103, the CPU 1010 changes the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300. More specifically, the CPU 1010 outputs a movement control signal via the input / output I / F device / movement device controller 2000 to change the position of the weighing container 300, and the tip of the thin tube nozzle 201 and the bottom of the weighing container 300. The relative distance is changed to a predetermined distance.

  In step S <b> 104, the CPU 1010 receives the weight that is the measurement value from the weighing meter 400 every predetermined time (for example, every second), and stores the received weight.

  In step S105, the CPU 1010 determines whether or not a certain time has elapsed. If this determination is YES, the CPU 1010 moves the process to step S106, and if NO, the CPU 1010 moves the process to step S104.

  In step S106, the CPU 1010 calculates the difference between the weight value stored in step S101 and the weight value stored in step S104. Specifically, the CPU 1010 calculates a linear expression between the predetermined time and the weight by the least square method based on the weight for each predetermined time stored in step S101. Next, the CPU 1010 similarly calculates a linear expression of the predetermined time and the weight by the least square method based on the weight for each predetermined time stored in step S104. Then, the CPU 1010 calculates the volatilization amount from the difference between the weight based on the linear formula in step S101 and the weight based on the linear formula in step S104.

FIG. 5 is a diagram illustrating measurement of the volatilization amount in the volatilization amount measurement apparatus 10 according to the embodiment of the present invention. As shown in FIG. 5 (1), the volatilization amount measuring apparatus 10 positions the tip of the thin tube nozzle 201 near the bottom of the container, shortens the distance 401 between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300, A first measurement is performed. That is, the volatilization amount measuring apparatus 10 discharges the liquid from the thin tube nozzle 201 at a predetermined flow rate, and continuously measures and stores the weight of the liquid flowing into the container with the weighing meter 400. Next, as shown in FIG. 5 (2), the volatilization amount measuring apparatus 10 calculates an equation (weight W ₀ = a × time t + c) from the stored digital value and the reading time by the least square method. Ask for. Further, to evaluate the linearity of the measurement results from the value of the correlation coefficient R ^2.

FIG. 6 is a diagram illustrating measurement of the volatilization amount at different distances in the volatilization amount measurement apparatus 10 according to the embodiment of the present invention. As shown in FIG. 6 (1), the volatilization amount measuring device 10 is different from FIG. 5 (1) in that the tip of the thin tube nozzle 201 is positioned away from the container bottom to a predetermined position, and the tip of the thin tube nozzle 201 and the weighing container The second measurement is performed in the same manner as the first measurement by increasing the distance 401 from the bottom of 300. That is, as in FIG. 5, the volatilization amount measuring apparatus 10 discharges the liquid from the thin tube nozzle 201 at the same prescribed flow rate as in FIG. 5, and continuously measures and stores the weight of the liquid flowing into the container with the weighing meter 400. . Next, as shown in FIG. 6 (2), the volatilization amount measuring apparatus 10 calculates an equation (weight W = b × time t + d) by the least square method from the digital value of the stored measurement value and the reading time. Ask. Further, to evaluate the linearity of the measurement results from the value of the correlation coefficient R ^2.

  FIG. 7 is a diagram illustrating estimation of the volatilization amount in the volatilization amount measuring apparatus 10 according to the embodiment of the present invention. It can be estimated that the difference between the inclination in FIG. 5 (2) and the inclination in FIG. 6 (2) is the amount 402 that the liquid that has flowed out of the thin tube nozzle 201 has volatilized before reaching the bottom of the weighing container 300. Therefore, if the initial values are the same, the volatilization amount Vtp with respect to the sample time becomes Vtp = a × t−b × t = (ab) × t (t: constant time (sample time)). Here, the volatilization after collecting in the container is the same amount in FIG. 5 and FIG. However, if the measurement value acquisition time is not evenly spaced, the sample is taken in a time that allows the time difference to be ignored. Also, when starting from an empty container, volatilization due to an increase in the surface area of the liquid in contact with air can be considered until the liquid fills the bottom surface in the initial stage. Start from the state.

  According to the present embodiment, the volatilization amount measuring apparatus 10 includes a thin tube nozzle 201 that forms a laminar flow 95 that flows continuously when the flow rate is smaller than a certain value at the tip of the nozzle 200, a tip of the thin tube nozzle 201, and weighing. A moving device 301 that changes a relative distance from the bottom of the container 300 and a control unit 410 that controls the change of the distance by the moving device 301 are provided. Then, the volatilization amount measuring apparatus 10 continuously measures the weight of the liquid flowing into the weighing container 300 from the thin tube nozzle 201 with the weighing meter 400 for a certain period of time. Then, the volatilization amount measuring apparatus 10 performs the first measurement, changes the relative distance between the tip of the thin tube nozzle 201 and the bottom of the weighing container 300, performs the second measurement, and performs the measurement by the first measurement. The difference between the measured weight and the weight measured by the second measurement is calculated. Therefore, the volatilization amount measuring apparatus 10 can accurately measure the volatilization amount of the liquid in the small flow rate region.

  As mentioned above, although embodiment of this invention was described, this invention is not restricted to embodiment mentioned above. The effects described in the embodiments of the present invention are only the most preferable effects resulting from the present invention, and the effects of the present invention are limited to those described in the embodiments of the present invention. is not.

DESCRIPTION OF SYMBOLS 10 Volatilization amount measuring device 95 Laminar flow 200 Nozzle 201 Narrow tube nozzle 300 Weighing container 301 Moving device 400 Weighing meter 410 Control part 501 Liquid quantity adjustment valve 502 Pressure adjustment valve 504 Test liquid tank 505 Pipe line

Claims (2)

A nozzle through which the liquid flows out, a weighing container for storing the liquid flowing out from the nozzle, and a weighing meter for measuring the weight of the liquid flowing into the weighing container, and the liquid flowing out from the nozzle is collected in the weighing container. A volatilization amount measuring device for measuring the volatilization amount up to
A capillary nozzle that forms a laminar continuous flow when the flow rate is smaller than a certain value at the tip of the nozzle;
Distance changing means for changing the relative distance between the tip of the thin tube nozzle and the bottom of the weighing container;
Control means for controlling the change of the distance by the distance changing means,
The control means includes
Measuring means for measuring the weight of the liquid flowing into the weighing container from the narrow tube nozzle by the weighing meter;
First measuring means for performing a first measurement by the measuring means;
A second measuring means for changing the distance and performing a second measurement by the measuring means;
A calculation unit that calculates a difference between the weight measured by the first measurement unit and the weight measured by the second measurement unit;
Volatilization measuring device. A nozzle through which the liquid flows out, a weighing container for storing the liquid flowing out from the nozzle, and a weighing meter for measuring the weight of the liquid flowing into the weighing container, and the liquid flowing out from the nozzle is collected in the weighing container. It is a method executed by a volatilization amount measuring device that measures the volatilization amount up to
The volatilization amount measuring device is
A capillary nozzle that forms a laminar continuous flow when the flow rate is smaller than a certain value at the tip of the nozzle;
Distance changing means for changing the relative distance between the tip of the thin tube nozzle and the bottom of the weighing container;
Control means for controlling the change of the distance by the distance changing means,
The control means has a measuring means for measuring the weight of the liquid flowing into the weighing container from the thin tube nozzle by the weighing meter,
The method
A first measuring step in which the control means measures by the measuring means;
A changing step in which the control means changes the distance;
A second measuring step in which the control means measures by the measuring means;
The method, wherein the control means includes a calculating step for calculating a difference between the weight measured by the first measuring step and the weight measured by the second measuring step.

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