KR102209047B1 - Apparatus And Method for Measuring Flux and Velocity of Flow in Drain Based on Measurement of the Electric conductivity - Google Patents

Abstract

The present invention relates to an apparatus and a method for measuring the flow speed and the flux of sewage, which is able to automatically input a certain volume of salty water at a single point of a sewage flow path, where sewage flows, to automatically measure changes in the electric conductivity in accordance with an input of salty water at another point of the sewage flow path, to constantly measure the flow speed and the flux, and to reduce the cost and time required for the measurement. According to the present invention, the apparatus for measuring the flow speed and the flux of sewage comprises: a salty water storage unit which stores salty water of a saturated concentration; a fixed-volume salty water supply unit which inputs a certain volume of salty water of the salty water storage unit each time at regular time intervals at a salty water input point which is apart from the measuring point of the sewage flow path toward an upstream side for a certain distance; a conductivity measuring unit which constantly measures the conductivity of sewage at the measuring point; and a calculation unit which calculates the flow speed and the flux based on the volume of changes in the conductivity measured by the conductivity measuring unit.

Description

Apparatus And Method for Measuring Flux and Velocity of Flow in Drain Based on Measurement of the Electric Conductivity}

The present invention relates to a method of measuring the flow rate and flow rate of sewage, and more particularly, to automatically inject a certain amount of brine at one point of a sewage passage through which sewage flows, and to drop salt water at another point of the sewage passage. The present invention relates to an apparatus and method for measuring the flow rate and flow rate of sewage so that the flow rate and flow rate of sewage can be measured by automatically measuring the change in electrical conductivity according to the result.

The flow rate in the sewer pipe should be maintained at an appropriate flow rate to perform its original functions, such as sediment flow problems, maintenance of proper water flow, and prevention of odor generation. Accordingly, the sewage system standard regulates the flow rate of sewage to be at least 0.6 m/s, and is reflected in the design.

In addition, the flow rate of sewage in the sewage pipe is an index that can confirm problems such as maintenance of water tightness of the pipe and incorrect connection of the pipe, and is an item that requires continuous measurement.

At present, the pressure conversion method using ultrasonic and immersion pressure gauges, which are generally used to investigate the flow of sewage, is being used.These measuring instruments allow the flow of sewage, such as the section where there is a lot of sediment in the sewage pipe, and the section where the reverse slope occurs due to differential settlement. There is a disadvantage that it cannot be installed in the changing section.

In addition, there is a problem that continuous measurement is impossible because artificial manipulation must be accompanied. In particular, to calculate the flow rate, it is necessary to measure the water depth as well as the flow rate, which makes continuous measurement difficult.

Korean Patent Registration No. 10-1015827 (registered on Feb. 11, 2011) Korean Patent Registration No. 10-1855746 (registered on May 2, 2018) Korean Patent Registration No. 10-0791319 (registered on December 27, 2007)

The present invention is to solve the above-described conventional problem, and an object of the present invention is to automatically inject a certain amount of brine at a point in a sewage passage through which sewage flows, and according to the dropping of salt water at another point in the sewage passage. Provides an apparatus and method for measuring the flow rate and flow rate of sewage that can automatically measure changes in electrical conductivity and measure the flow rate and flow rate of sewage, enabling continuous measurement of the flow rate and flow rate, and reducing the cost and time required for measurement. Is to do.

The apparatus for measuring the flow rate and flow rate of sewage according to the present invention for achieving the above object comprises: a salt water storage unit for storing salt water having a saturated concentration; A salt water quantity supply unit for dropping a predetermined amount of salt water from the salt water storage unit at a predetermined time interval at a salt water input point separated from a measuring point of the sewage flow path to an upstream side; A conductivity measurement unit that continuously measures the conductivity of sewage at the measurement point; It includes; a calculation unit for calculating the flow rate and flow rate based on the amount of change in the conductivity measured by the conductivity measurement unit.

When the conductivity measured by the conductivity measurement unit is defined as the base conductivity at a time point (t ₀ ) at which salt water is introduced by the salt water quantity supply unit is defined, the calculation unit measures when the salt water is dropped by the salt solution quantity supply unit. Below from the time difference between the flow rate calculation time point (t ₁ ) and the time point at which the base conductivity is measured (t ₀ ), and the distance from the salt water input point to the conductivity measuring unit (d), at which the measured conductivity becomes n times or more of the base conductivity Equation of

The flow velocity (υ) can be calculated from.

In addition, the calculation unit calculates the average conductivity C _av between the recovery point (t ₂ ) and the flow rate calculation point (t ₁ ) at which the dropping of salt water by the salt water quantity supply unit is terminated and the conductivity is restored to the base conductivity again, and the calculated When the average conductivity is defined as C _av and the ratio of the conductivity of saturated brine is defined as the saline dilution ratio R, for the total saline input volume V and the final flow time t _t (t _t = t ₂ -t ₁ ) of saline , The equation below

The flow rate Q can be calculated by.

N may be 1.5.

The salt water quantitative supply unit may include a timer switch and a metering pump operated at a predetermined period by the timer switch.

The method of measuring the flow rate and flow rate of sewage using the flow rate and flow rate measuring device of the present invention as described above,

(S1) measuring the basal conductivity at a point in time (t ₀ ) at which salt water is introduced at the measurement point of the sewage channel;

(S2) dropping a saturated amount of brine at a predetermined time interval at a salt water input point separated by a predetermined distance upstream from the measurement point, and continuously measuring the conductivity at the measurement point; And,

(S3) The flow rate is determined based on the time difference between the flow rate calculation time point (t ₁ ) at which the conductivity measured in step S2 becomes n times or more of the base conductivity and the time point (t ₀ ) at which the base conductivity is measured in step S1. Calculating;

It may include.

In addition, in step S3, the following equation

The flow velocity (υ) can be calculated from.

In the step S3, the average conductivity C _av is calculated between the recovery point (t ₂ ) and the flow rate calculation point (t ₁ ) at which the dropping of salt water is terminated and the conductivity is restored to the base conductivity again, and the calculated average conductivity is C _When the ratio of the conductivity of _av to the saturated concentration of brine is defined as the brine dilution ratio R, for the total amount of saline input V and the final flow time of brine t _t (t _t = t ₂ -t ₁ ), the following math expression

The flow rate Q can be calculated by.

In the step S2, the salt water having a saturated concentration may be dropped by a predetermined amount at regular time intervals by a salt water quantitative supply unit including a timer switch and a metering pump operated at a predetermined cycle by the timer switch.

According to the present invention, a certain amount of salt water is automatically dropped at one position in a sewage passage (for example, a sewage pipe), and a change in electrical conductivity according to the dropping of salt water at another position in the sewage passage is measured to measure the flow rate and flow rate of sewage. It has the effect of being able to measure continuously and accurately.

1 is a block diagram schematically showing the configuration of a flow rate and flow rate measuring apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a flow rate and a flow rate measurement method according to an embodiment of the present invention.

The embodiments described in the present specification and the configurations shown in the drawings are only preferred examples of the disclosed invention, and there may be various modifications that may replace the embodiments and drawings of the present specification at the time of filing of the present application.

Hereinafter, an apparatus and method for measuring a flow rate and a flow rate of sewage will be described in detail according to embodiments described below with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same components.

1 shows the configuration of a flow rate and flow rate measurement device according to an embodiment of the present invention, wherein the flow rate and flow rate measurement device is a salt water storage unit 10 for storing saturated salt water, and a measurement point of a sewage channel (sewer pipe) A salt water quantity supply unit that drops a certain amount of salt water in the salt water storage unit 10 at a certain time interval at a salt water input point located at a certain distance from the upstream side, and a conductivity measuring unit that continuously measures the electrical conductivity of sewage at the measurement point. (30), and a calculation unit 40 that calculates a flow rate and a flow rate based on the amount of change in conductivity measured by the conductivity measurement unit 30.

The brine storage unit 10 may be formed of a tank for storing saturated brine (NaCl, KCl, etc.) to be introduced into the sewage passage.

The salt water quantitative supply unit transfers the saturated salt water stored in the salt water storage unit 10 to a salt water input point at a certain distance (d) upstream from the measurement point of the sewage channel, preferably a certain amount at a certain time interval in the manhole. It is structured to be able to drop each one continuously. In this embodiment, the salt water quantitative supply unit, a timer switch (not shown) and a metering pump 20 that is operated at a predetermined period by the timer switch (not shown) to drop the salt water in the salt water storage unit 10 to the measurement position. ) Can be included. By continuously dropping salt water into sewage by the salt water quantitative supply unit having such a configuration, it is possible to measure the electrical conductivity.

The conductivity measurement unit 30 may be configured by applying a known conductivity meter capable of measuring electrical conductivity, and measures the electrical conductivity of sewage at a measurement location where salt water is dropped. Electrical conductivity is a value representing the degree to which an electrolyte existing in water can transfer electric charges, and various electrolytes exist in domestic sewage and have an electrical conductivity of about 500 to 2000 µs/cm. When saturated brine is dropped into sewage, the electrical conductivity is greatly increased. Since the electrical conductivity changes according to the flow characteristics of the sewage flow path, the flow rate and flow rate can be calculated by analyzing this pattern.

The calculation unit 40 is programmed to calculate the flow rate and flow rate of sewage based on a predetermined equation by using the change in electrical conductivity. When the conductivity measured by the conductivity measuring unit 30 is defined as the base conductivity at the time point (t ₀ ) at which salt water is introduced by the salt water quantitative supply unit, the conductivity measured when the salt water is dropped by the salt water quantitative supply unit The flow rate (υ) is calculated from Equation 1 below through a time difference between the time point t _{1 of which} is _equal to or greater than n times the base conductivity and the time point t ₀ at which the base conductivity is measured. In Equation 1 below, d is the distance between the salt water dropping point and the installation point of the conductivity measuring unit 30.

In addition, the calculation unit 40 calculates the average conductivity C _av between the recovery point (t ₂ ) and the flow rate calculation point (t ₁ ) at which the dropping of salt water by the salt water quantity supply unit is terminated and the conductivity is restored to the base conductivity again, When the calculated average conductivity is defined as the ratio of the conductivity of C _av and the conductivity of the saturated brine to the saline dilution ratio R, the total amount of saline input V and the final flow time of saline t _t (t _t = t ₂ -t ₁ For ), the flow rate Q is calculated by Equation 2 below.

Since the range of the basal conductivity in sewage is large, it is necessary to drop brine that can increase the conductivity by about 3 to 4 times the basal conductivity in order to determine whether the brine reaches or not. If the amount of brine is excessive, it may affect the flow rate of sewage, so the input amount should be minimized.

A method of measuring the flow rate and flow rate of sewage using the flow rate and flow rate measuring device of the present invention will be described with reference to FIGS. 1 and 2 as follows.

In order to measure the flow rate of sewage, the flow time of the brine is measured. First, the base conductivity at the measurement point is measured with the conductivity measuring unit 30 at the point of time (t ₀ ) just before the brine is introduced at the point of saline water input in the sewage channel.

Subsequently, a predetermined amount of saturated salt water is dropped at a predetermined time interval at a measurement point of a sewage channel using the salt water quantitative supply unit, and the conductivity of the measurement point is continuously measured using the conductivity measuring unit 30. The electrical conductivity measured after dropping of salt water gradually increases. The point in time when the conductivity increases by a certain amount over the base conductivity by salt water is called t ₁ , and this is called the flow rate calculation point (t ₁ ). At this time, it is necessary to distinguish between an increase in conductivity due to the arrival of brine and an increase in conductivity due to the inflow of sewage with high conductivity. That is, even if the conductivity starts to increase than the base conductivity, it is necessary to set a value that cannot be regarded as an increase in conductivity due to the arrival of salt water. For this reason, it is necessary to increase the conductivity by 3-4 times or more compared to the base conductivity. Therefore, if the conductivity increase does not rise to more than 1.5 times the base conductivity, it is not judged that the brine has reached the measurement point.

If the conductivity is continuously increased by 1.5 times or more compared to the base conductivity, the point of increase in conductivity is regarded as the flow velocity calculation point (t ₁ ). If the distance between the salt water dropping point and the installation point of the conductivity measuring unit 30 is d, the flow velocity can be obtained by Equation 1 above.

The time point at which the saline dropping is complete and the conductivity returns to the base conductivity is called t ₂ , and the electrical conductivity is measured from t ₁ to t _2, and the average conductivity C _av of this section is calculated. And the ratio of the calculated average conductivity C _av and the conductivity of the brine at the saturation concentration (approximately 200 ms/cm) is defined as the saline dilution ratio R, and the total amount of saline input V and the final flow time t _t (t _{Based on t} = t ₂ -t ₁ ), the flow rate (Q) is calculated by Equation 2 above.

According to the present invention, a certain amount of salt water is automatically dropped at one position in a sewage passage (for example, a sewage pipe), and a change in electrical conductivity according to the dropping of salt water at another position in the sewage passage is measured to measure the flow rate and flow rate of sewage. Can be measured continuously and accurately.

Currently, a watertightness test is being conducted to select a sewage pipe maintenance project, and such a watertightness test requires a lot of cost and time because expensive equipment and professional manpower to operate it are required. However, the present invention can automatically and continuously measure the change in flow rate and flow rate at a measurement point with a simple configuration, so that the cost and time required for measurement can be greatly reduced.

In addition, the flow rate and flow rate measurement device of the present invention can be utilized to evaluate the point where the flow rate in the pipe is lowered or sewage is stored due to differential settlement, damage, etc. In such a sewage pipe, problems such as leakage, reduction in water flow, and occurrence of odors occur, so a countermeasure can be prepared through automatic measurement of the flow rate and flow rate. In addition, since it is possible to continuously monitor sporadic sections, there is an advantage in that faster data collection is possible in selecting a section for priority maintenance among all sewage pipes.

In the above, the present invention has been described in detail with reference to the embodiments, but those of ordinary skill in the art to which the present invention pertains will be able to make various substitutions, additions, and modifications within the scope not departing from the technical idea described above. It is natural, and it should be understood that such modified embodiments also belong to the protection scope of the present invention defined by the appended claims below.

10: salt water storage unit 20: metering pump
30: conductivity measuring unit 40: calculating unit

Claims (9)

A brine storage unit for storing saturated brine;
A salt water quantity supply unit for dropping a predetermined amount of salt water from the salt water storage unit at a predetermined time interval at a salt water input point separated from a measuring point of the sewage flow path to an upstream side;
A conductivity measurement unit that continuously measures the conductivity of sewage at the measurement point;
An operation unit calculating a flow rate and a flow rate based on the change in conductivity measured by the conductivity measurement unit;
Including,
When the conductivity measured by the conductivity measurement unit is defined as the base conductivity at a time point (t ₀ ) at which salt water is introduced by the salt water quantity supply unit is defined, the calculation unit measures when the salt water is dropped by the salt solution quantity supply unit. Below from the time difference between the flow rate calculation time point (t ₁ ) and the time point at which the base conductivity is measured (t ₀ ), and the distance from the salt water input point to the conductivity measuring unit (d), at which the measured conductivity becomes n times or more of the base conductivity Equation of

Calculate the flow rate (υ) from
The calculation unit calculates the average conductivity C _av between the recovery point (t ₂ ) and the flow rate calculation point (t ₁ ) at which the dropping of salt water by the salt water quantity supply unit is terminated and the conductivity is restored to the base conductivity again, and the calculated average When the conductivity is defined as C _av and the ratio of the conductivity of the saturated brine to the brine dilution ratio R, for the total amount of saline input V and the final flow time t _t (t _t = t ₂ -t ₁ ) of the brine, Equation below

A sewage flow rate and flow rate measuring device that calculates the flow rate (Q) by. delete delete The apparatus of claim 1, wherein n is 1.5. The apparatus of claim 1, wherein the salt water constant amount supply unit includes a timer switch and a metering pump operated at a predetermined period by the timer switch. (S1) measuring the basal conductivity at a point in time (t ₀ ) at which salt water is introduced at the measurement point of the sewage channel;
(S2) dropping a saturated amount of brine at a predetermined time interval at a salt water input point separated by a predetermined distance upstream from the measurement point, and continuously measuring the conductivity at the measurement point; And,
(S3) The flow rate is determined based on the time difference between the flow rate calculation time point (t ₁ ) at which the conductivity measured in step S2 becomes n times or more of the base conductivity and the time point (t ₀ ) at which the base conductivity is measured in step S1. Calculating;
Including,
In step S3, the following equation

The flow rate (υ) is calculated from
The average conductivity C _av is calculated between the recovery point (t ₂ ) and the flow rate calculation point (t ₁ ) at which the saline dropping is finished and the conductivity is restored to the base conductivity, and the calculated average conductivity is C _av and the saturation concentration. When the ratio of the conductivity of the brine is defined as the brine dilution ratio R, for the total amount of saline input V and the final flow time of brine t _t (t _t = t ₂ -t ₁ ), the following equation

The flow rate and flow rate measurement method of sewage to calculate the flow rate (Q) by. delete delete The flow rate of sewage according to claim 6, wherein in the S2 step, the salt water quantitative supply unit including a timer switch and a metering pump operated at a certain period by the timer switch is dropped by a certain amount of salt water having a saturated concentration at a certain time interval. And flow measurement method.

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