JPS6166946A - Measuring method of concentration - Google Patents

Abstract

PURPOSE:To eliminate a pressure drop loss due to tube friction resistance and an error due to the spouting of measurement liquid at a cell peak by detecting pressure differences of constant intervals at a horizontal part and pressure differences of the same intervals with the horizontal part at a vertical part. CONSTITUTION:The liquid 12 reserved in a tank 11 is fed through vertical piping 14 and horizontal piping 15 which are equal in diameter to a pump 18 and made of the same material. Pressure detectors 16-19 are fitted to walls of those pipes 14 and 15 so that the interval between the detectors 16 and 17 of the pipe 14 and that of the detectors 18 and 19 of the pipe 15 are equal to each other. Signals (a) and (b) of pressure detected by the detectors 16 and 17 provided to the pipe 14 are inputted to a differential pressure detector 21, which outputs their pressure difference as a differential pressure signal (f). Similarly, signals (c) and (d) of pressure detected by the detectors 18 and 19 of the pipe 15 are inputted to a differential pressure detector 20, which outputs a differential pressure signal (e). Those signals (e) and (f) are used by a computing element 22 for processing to calculate corrected differential pressure, thereby outputting a pressure signal (g) for concentration arithmetic.

Description

[Detailed description of the invention]

l Industrial Application Fields] Liquids or liquids 71. ) - is a common method to control the concentration of solutes or suspended particles by measuring the density of a fluid such as For product concentration tube 1, the level is 5ff L for d. [Prior Art] The conventional method of continuous phase ', 1' for density determination of liquid or slurry will be explained in detail based on Section 21-2. A pump 3 is used to send a stream 1 (2) from a tank 1 that stores a fluid 2 such as liquid or slurry through an IZ pipe 4.A density measurement pipe 9 branching from the main pipe 4 is connected to one pile. A part of the fluid 2 being sent through the pump 3 is sent to the measuring cell 6 by a predetermined current through the bulge 5, overflowing from the top 7 of the measuring cell, and flowing into the overflow pipe. 8 through 1
After 11 hours, it was returned to tank 2. A pressure detector 10 is attached to one wall of the 611 measurement cell 6,
The pressure detector 10 detects the pressure of the fluid flowing through the measuring cell 6 up to the point 7 with a specific gravity of 41 from the position A.1. The density of the fluid 2 is calculated from the monthly force detected by the pressure detector 10 using the following formula. Z:
Detected from part n4 MH,'? − length l+n l ,
p: dense 751 kg'm"] f, 4 ru. 1 The problem that Zenmei tries to solve +: jjfS-Next J,
In law, the flow 1+2 of τ night or S”i II- etc.
When flowing through the cell 6, the pipe friction resistance 1 causes the loss of 141 during the flow, and there is no L end. Father measurement tenth 6j

[Taking into account the taste of one jet in the first part, when handling the powder, prevent the sedimentation of the powder in the hill 6.
In order to do this, it is easy to make a mistake in IJ [4] because the minimum flow velocity is present in the particles.5. 1. Means to solve the problem ゛] The horn θ of this determination is to separate the ejaculated flow chamber into the horizontal part and the vertical part.
! The flow velocity is caused to flow through a continuous pipe of the same diameter and made of the same material, and the pressure υ between the intervals in the horizontal part is υ! Possible and
Detect the It: JJ difference between the intervals equal to the interval at the horizontal part in 1° 1 part of the I1 wheel, and calculate the difference between the pressure difference at 111 parts of water and the 1.1 horn difference at the di straight part. 1 of the interval where the pressure difference was found This is caused by a low static IF due to frictional resistance.On the other hand, the pressure difference at the vertical portion is the sum of the static pressure drop caused by the frictional resistance between the two fluids and the pipe when they flow, and the back pressure. If the intervals for calculating this pressure difference are made equal for the horizontal and vertical parts, the drop in static pressure will be the same, so by calculating the difference in pressure difference, only the back pressure can be determined. Divide it by the length to get the density. [Example] Below is a drawing showing the method of the present invention. <f I will explain while using L. He who is stored in Tank 11? +'+1111 fluid 12i=t. The liquid is fed by a pump 13 through vertical piping 14 and water IV piping 15, which have the same diameter and are made of the same material. These pipes 14 and 15'l? Pressure detectors 16, 17, 18, and 19 are installed at each 1 m. It's ok, II'i straight pipe 14 l-1-:) J detector 1
6 to pressure detector 1F and water xll piping 15
The distances from the pressure detector 18 to the pressure detector 191 are set to be equal. First, the pressure signals a and 1 detected by the pressure detectors 16 and 17 provided in the vertical pipe 14 are input to the differential pressure detector 21, and the pressure difference is transmitted as a differential pressure signal. Similarly, in the underwater pipe 15, the pressure signal C (1) detected by the pressure detector 18 and the pressure detector 19 is manually input to the differential pressure detector 20, and the pressure difference is transmitted as the differential pressure signal @. Differential pressure signal from differential pressure detector 2° and differential pressure detector 2
Using the differential pressure signal [F] from 1, the computing unit 22 performs arithmetic processing according to the following equation to obtain a supplementary iE differential pressure and outputs a pressure signal @ for density calculation. P, -1',, -P where Pl is vertical differential pressure, P2 is horizontal differential pressure. P: Specific gravity calculation ability. The preset device 24 outputs the installation distance 2 between the pressure detectors 16 and 17 as a signal to the density calculator 23. The density is calculated and displayed using the formula ( ) together with the density calculation confidence g from the calculator 22. The inventors prepared a slurry-like fluid 12 shown in Table 1 in a tank 11, and conducted a test to confirm the method of the present invention by pumping the fluid through a vertical pipe 14 and a horizontal pipe 15 using a pump 13. Note that the distance between the pressure detector] 6 and the pressure detector 17 and the distance between the pressure detector 18 and the pressure detector 19 are both 2.
It was set as m. The composition results of the slurry prepared in Table 1 are shown in Table 2, and the measured results and calculated values were almost in agreement. Table 2 Results (Temperature ゛23°(1) [Effect] According to the method of the present invention), the pressure loss error due to pipe friction resistance observed in the conventional measuring force method and the
It was possible to eliminate the error caused by the spraying of the measurement liquid at the n part.

[Brief explanation of drawings]

Figure 1 shows the flow when measuring specific gravity according to the present invention.
FIG. 2 is a flowchart showing the flow when measuring specific gravity in a conventional method. 11... Tank, 12 Fluid, 13. Pump, 14
・Takuhaku Piping, 15・Water) Do Piping, 16・17・18・
19...Pressure detector, 20.21...Differential pressure detector,'
22... Arithmetic unit 1st tomoe

Claims (1)

[Claims] The fluid to be measured is passed through a continuous pipe of the same diameter and made of the same material, consisting of a horizontal section and a vertical section. The density of the fluid is determined by detecting the pressure difference and dividing the difference between the pressure difference in the horizontal part and the pressure difference in the vertical part by the length of the interval from which the pressure difference was determined. How to measure.