JP2013019736A - Steam usage measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To individually and easily measure steam usages of respective steam using apparatuses already installed in a factory etc., without using a steam flowmeter.SOLUTION: There is provided a steam usage measurement device 11 which measures the steam usage of a steam using apparatus 6 connected to a boiler 1 through a steam line 5, and includes: differential pressure detection means 13 of detecting the differential pressure between an upstream side and a downstream side of a steam valve 7 provided to the steam line 5; time measurement means 14 of measuring the operation time of the steam valve 7; and calculation means 15 of calculating the steam usage on the basis of preset characteristic values of the steam valve 7, the differential pressure detected by the differential pressure detection means 13, and the operation time measured by the time measurement means 14.

Description

  The present invention relates to a steam usage measuring device for measuring a steam usage in a steam using device.

  Steam is generally used as a heat source in factories and buildings, and a boiler is installed as a device for generating the steam. A plurality of such boilers are usually installed, and the steam generated in each boiler is supplied to each steam using equipment such as a factory via a steam line. A steam header that functions as a buffer tank is provided in the middle of the steam line, and the operation (combustion amount) of each boiler is controlled based on the steam pressure in the steam header.

  In the factory or the like, the amount of steam used is measured as an energy saving diagnosis. This is for discovering the loss of steam due to heat dissipation or leakage, and for setting the optimum boiler unit control pattern according to the variation in the amount of steam used. As a means for measuring the amount of steam used, there is a steam flow meter. However, even if this steam flow meter is installed, it is often only the main pipe in the steam line, and in the branch pipe branched from the main pipe and connected to each steam using device, the steam flow meter Is rarely provided. If the amount of steam used in each steam-using device at the end of the branch pipe cannot be grasped, it is difficult to perform highly effective energy saving diagnosis.

  If a steam flow meter is additionally attached to the branch pipe, extra work is required, which is not practical. Moreover, although there exists a thing of patent document 1 as an apparatus which measures a steam usage amount without using a steam flow meter, this is to the function which measures the steam usage amount in each said steam usage apparatus separately. There was no need for further improvement.

JP-A-9-119602

  The problem to be solved by the present invention is to enable individual and simple measurement of the amount of steam used in each steam-using device already installed in a factory or the like without using a steam flow meter.

  This invention is made in order to solve the said subject, The invention of Claim 1 is a steam usage measurement which measures the steam usage in the steam usage apparatus connected to the boiler via the steam line. A pressure difference detecting means for detecting a pressure difference between an upstream side and a downstream side in a differential pressure generating member provided in the steam line; and a time for which the steam flows through the differential pressure generating member. Time measuring means and calculating means for calculating a steam usage based on a preset characteristic value of the differential pressure generating member, a differential pressure detected by the differential pressure detecting means, and a time measured by the time measuring means It is characterized by having.

  According to the invention of claim 1, based on the characteristic value of the differential pressure generating member, the differential pressure between the upstream side and the downstream side of the differential pressure generating member, and the time during which steam flows through the differential pressure generating member, The amount of steam used in the steam-using device can be calculated, and the amount of steam used in each existing steam-using device can be measured individually and simply without using a steam flow meter.

  The invention according to claim 2 is the invention according to claim 1, wherein the differential pressure generating member is a steam valve, the characteristic value is a Cv value of the steam valve, and the time is an operation of the steam valve. It is characterized by time.

  According to the second aspect of the present invention, since the Cv value is a known numerical value as a flow characteristic value in a commercially available steam valve, the amount of steam used can be easily obtained without performing a complicated calculation.

  According to the present invention, it is possible to individually and easily measure the amount of steam used in each steam-using device already installed in a factory or the like without using a steam flow meter. Therefore, highly effective energy saving diagnosis can be performed, which is effective in realizing energy saving.

It is explanatory drawing which shows one Example of this invention. It is explanatory drawing which expands and shows the structure of the principal part of FIG.

  Next, an embodiment for carrying out the present invention will be described. The steam usage measuring device according to the present invention is used to measure the steam usage in an existing steam using equipment in a factory or a building.

  The said steam using apparatus is connected to the boiler via the steam line. This steam line is provided with a differential pressure generating member. The differential pressure generating member is a steam valve, a flow rate adjusting orifice member, or the like. The steam valve controls the supply of steam, and is electrically controlled using an electric valve or an electromagnetic valve. The steam consumption measuring device according to the present invention includes a differential pressure detecting means, a time measuring means, and a calculating means.

  First, the differential pressure detecting means detects a differential pressure between the upstream side and the downstream side of the differential pressure generating member. In detecting the differential pressure, if there is an existing pressure sensor in the steam line, a signal from the pressure sensor is taken in. Alternatively, the pressure value obtained by visually observing the pressure sensor may be manually input. Further, when there is no pressure sensor, a pressure sensor for detecting a differential pressure may be temporarily attached to the steam line. Compared to the installation of the steam flow meter, the installation of the pressure sensor is relatively easy.

  Next, the time measuring means measures the time during which steam flows through the differential pressure generating member. When the differential pressure generating member is the steam valve, the operation time of the steam valve is measured. That is, the time for which the steam valve is open is measured. In measuring the time, an operation signal to the steam valve is taken in. The operation signal may be captured directly or the current may be measured without contact with the signal line. It is also possible to manually input data by measuring the time separately.

Further, the calculating means uses the steam based on the preset characteristic value of the differential pressure generating member, the differential pressure detected by the differential pressure detecting means, and the time measured by the time measuring means. The amount is calculated. As the characteristic value, in the case of the steam valve, the Cv value of the steam valve is used. The Cv value is a numerical value representing the flow rate in terms of gal / min when water of 60 ° F. (15 ° C.) is flowed while maintaining the differential pressure before and after the valve at 1 psi (6.9 kPa). If so, it is a numerical value published by the manufacturer. When the flow rate is Q [gal / min], the specific gravity is G, and the differential pressure is ΔP [psi], the Cv value is represented by Cv = Q × (G ÷ ΔP) ^1/2 . Based on this formula, after performing unit conversion, the steam flow rate, that is, the steam usage [kg / h] is obtained. Since steam is supplied by the amount used in the steam-using device, the steam flow rate in the steam line corresponds to the amount of steam used in the steam-using device.

  As for the steam usage, the time zone is divided into predetermined sub-sections (for example, every minute), and the flow rate in this sub-section is multiplied by the operating time of the steam valve to obtain the steam usage [kg / h] and save the data. If the horizontal axis is time and the vertical axis is the steam usage, the change in the steam usage can be seen well. Also, by integrating the amount of steam used, the accumulated amount of steam used per day can be obtained. Furthermore, if the flow rate of steam flowing through the steam line is substantially constant, the amount of steam used per day is obtained by multiplying this by the operating time of the steam valve.

  As described above, since the amount of steam used in the steam-using device can be determined, even when there are a plurality of the steam-using devices, the amount of steam used for each steam-using device can be measured individually and simply. . Therefore, highly effective energy saving diagnosis can be performed, and whether or not there is any steam loss due to heat dissipation or leakage can be individually and simply determined for each steam-using device. Moreover, the fluctuation | variation of the steam usage in each said steam using apparatus can be grasped | ascertained correctly, the optimal boiler number control pattern can be set according to the fluctuation | variation (a steam is generated efficiently and efficiently), It is effective in realizing energy saving.

  An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, three boilers 1 are installed, and a multi-can installation system for the boiler 1 is configured. Each boiler 1 is provided with a main steam valve 2, and a main steam line 3 is connected to each outlet thereof. The downstream end of the main steam line 3 is connected to a steam header 4 that functions as a buffer tank. The operation (combustion amount) of each boiler 1 is controlled based on the steam pressure in the steam header 4.

  In addition, a plurality of steam lines 5 are connected to the steam header 4, and each of these steam lines 5 is directly or branched and each downstream end thereof is connected to a plurality of steam using devices 6. . Each steam line 5 is provided with a steam valve 7 for controlling the supply of steam to each steam using device 6 corresponding to the number of the steam using devices 6 (in this embodiment). The steam valve 7 corresponds to a differential pressure generating member). These steam valves 7 are respectively connected to a steam flow rate control device 8 via signal lines (reference numerals omitted). The steam flow rate control device 8 depends on the operating status of each steam-using device 6. The opening / closing or opening of each steam valve 7 is controlled. In each of the steam using devices 6, a drain line 10 having a steam trap 9 is connected.

  Furthermore, a steam flow rate measuring device 11 according to the present invention is provided, and a pressure sensor 12 is connected to the steam flow rate measuring device 11 via a signal line (reference number omitted). One pressure sensor 12 is provided on each of the upstream side and the downstream side of the steam valve 7. The pressure sensor 12 may be an existing one in the steam line 5 or may be additionally attached for measurement. The pressure sensor 12 may be a single sensor as long as it detects the differential pressure between the upstream side and the downstream side of the steam valve 7. Further, the steam flow measuring device 11 receives an operation signal of the steam valve 7 via a signal line (reference number omitted). This operation signal may be taken in from the steam flow control device 8 that issues a control signal to the steam valve 7.

  FIG. 2 shows an enlarged configuration of the main part of FIG. The differential pressure detecting means 13 detects a differential pressure between the upstream side and the downstream side of the steam valve 7 based on signals from the two pressure sensors 12. The time measuring means 14 measures the operation time (open time) of the steam valve 7 based on the operation signal taken from the steam valve 7. Further, the calculating means 15 is based on the preset characteristic value of the steam valve 7, the differential pressure detected by the differential pressure detecting means 13, and the operating time measured by the time measuring means 14. Calculate the steam consumption.

  The Cv value of the steam valve 7 is used as the characteristic value. The Cv value is input in advance to the steam flow rate measuring device 11 as a table corresponding to the diameter and type of the steam valve 7, and is selected therefrom. When the steam valve 7 adjusts the opening degree, the Cv value also changes according to the opening degree, but the correspondence data between the opening degree and the Cv value is also stored in the table and used. In this case, the opening information of the steam valve 7 is also taken into the steam flow measuring device 11.

  In this way, the amount of steam used in each steam-using device 6 is calculated. The calculated steam usage is stored as data in the steam flow measuring device 11. And this data is analyzed suitably and an energy saving diagnosis is performed. For example, the steam usage measured by the steam flow measuring device 11 is compared with the steam usage calculated from the operating state of each steam-using device 6 to determine whether there is any steam loss due to heat dissipation or leakage. To do. Moreover, it is also possible to apply to the abnormality detection of each said steam using apparatus 6. FIG. Furthermore, an optimal boiler number control pattern is set in accordance with the temporal fluctuation of the steam usage in each steam-using device 6.

  According to the above configuration, the amount of steam used in each steam-using device 6 can be measured individually and simply without using a steam flow meter, and a highly effective energy-saving diagnosis can be performed. .

  By the way, when the steam valve 7 is also provided in the main steam line 3, the differential pressure between the upstream side and the downstream side of the steam valve 7, the operation time, and the Cv are similar to the above-described configuration. The steam flow rate of the main steam line 3 may be obtained based on the value. By doing so, the fluctuation | variation of the total value of the steam usage-amount of each said steam using apparatus 6 can be measured.

DESCRIPTION OF SYMBOLS 1 Boiler 5 Steam line 6 Steam use apparatus 7 Steam valve 11 Steam flow measuring device 13 Differential pressure detection means 14 Time measurement means 15 Calculation means

Claims (2)

  A steam usage measuring device for measuring a steam usage in a steam using device connected to a boiler via a steam line, between an upstream side and a downstream side in a differential pressure generating member provided in the steam line A differential pressure detecting means for detecting a differential pressure; a time measuring means for measuring a time during which steam flows through the differential pressure generating member; and a preset characteristic value of the differential pressure generating member, which is detected by the differential pressure detecting means. And a calculating means for calculating the steam usage based on the differential pressure and the time measured by the time measuring means. The steam usage measurement according to claim 1, wherein the differential pressure generating member is a steam valve, the characteristic value is a Cv value of the steam valve, and the time is an operation time of the steam valve. apparatus.

Images