KR20040027820A - dreg sludge height and flow rate measurement system using pressure gauge and sewage water level and velocity gauge - Google Patents

Abstract

PURPOSE: A system for measuring height and flow rate of sewage sludge in a sewage water pipe is provided to instantly measure the height and flow rate of sewage sludge by transmitting data about the sewage sludge to a control center in real time. CONSTITUTION: A system for measuring height and flow rate of sewage sludge includes a pressure meter(3) capable of precisely measuring height of sewage sludge and flow rate of sewage water in a sewage water pipe. A water gauge(2) and a current meter(1) are provided to measure a water level and flux of sewage water in the sewage water pipe. A device is provided to calculate real height of sewage sludge and real flow rate of sewage water in a sewage water pipe based on measuring values detected by the pressure meter(3), the water gauge(2) and the current meter(1). Data stored in a memory are displayed in a display panel.

Description

Dreg sludge height and flow rate measurement system using pressure gauge and sewage water level and velocity gauge

The present invention is installed on the inner wall of the sewage pipe and flow gauge and sewage gauge applicable to the sewer pipe and underground and underwater, the upper part is a built-in level gauge for measuring the level of the flowing fluid, the lower part The present invention relates to a sediment height and flow measurement system capable of accurately measuring sediment height of a sewer pipe and a flow rate of a flowing fluid by installing a seismograph capable of simultaneously measuring sediment pressure and fluid pressure.

The apparatus for measuring a pipeline of a conventional sewage system is only installed / operated in a specific part of the sewer system by measuring a flow rate in the pipeline using a flow rate and a water level measurement system. However, there is a problem that the flow rate is changed by the height of the sediment in the sewer pipe can not be measured accurately.

The technical problem to be achieved by the present invention is to recognize the problems of the prior art to install a flowmeter inside the sewage pipe and to install a water gauge to measure the water level at the top of the sewer pipe, the bottom of the sediment pressure and flowing fluid The purpose is to implement a device that can accurately measure the flow rate and sediment height in the pipeline by properly monitoring all sewage pipeline systems with sediment by incorporating a pressure gauge to measure the combined pressure. That is, the sum of the sediment and the flowing fluid and the pressure of the fluid and the sediment can be measured using the flowmeter and the manometer, which are the respective measuring systems. It measures the exact flow rate by height and flow rate, and each measured value is transmitted to the control center in real time through the relevant information and communication network so that the sediment height and flow rate of the sewage pipe can be monitored without time delay. The aim is to enable more accurate and quicker maintenance and repair.

In addition, the present invention by using the measurement system designed and manufactured as described above to accurately measure the height of the sediment of the sewer pipe or the flow rate of the flowing fluid to significantly improve the operating efficiency of the sewage system (system) to peak summer demand (peak time), etc. It is another purpose to prevent the accidents occurring in advance and to maximize the operational efficiency of the sewage terminal treatment plant by accurately predicting the time of dredging pipeline.

1 is a position and the sewer pipe structure of the sensor according to the invention.

2 is a sewer pipe structure for measuring the height of the sediment.

3 is a structure of a commercial earth pressure gauge

<Explanation of symbols for main parts of drawing>

One ; Flowmeter 2; water gauge

3; Pressure gauge 4; Box

The present invention relates to a device that can accurately measure the flow rate and the sediment height of the flowing fluid by excluding the flow measurement error due to the sediment by measuring the height and the flow rate of the sediment accumulated in the sewer pipe at the same time. Looking specifically at the constituent means according to the present invention, by installing a suitable protective structure inside the sewer pipe in the form of a box (box) to withstand a strong flow rate to the wall inside the flow rate, water gauge and earth pressure gauge inside the box Fix and install. 1 is a cross-sectional view of various sewer pipes of a general round and square shape, a flow meter is located inside the sewer pipe, the central top end of the sewer pipe is installed with a Doppler-type ultrasonic level measurement system for measuring the level of the flowing fluid, The lower part is equipped with a vibrating string and diaphragm type earth pressure measuring system that can measure the pressure of the flowing fluid and the deposit. A typical measuring instrument capable of measuring the flow rate is a Doppler type ultrasonic flow meter, which generates ultrasonic waves at a transmitter and receives reflected waves reflected from bubbles or suspended particles in water, which are flow liquids. do. That is, the flow velocity is measured by using the ultrasonic frequency emitted by the measuring instrument and the scattering movement of the particles or the scattering movement of the flowing fluid.

In FIG. 2, the non-contact ultrasonic level meter for measuring the water level emits sound waves from the detector surface, and detects the water level by measuring the time when the ultrasonic wave is reflected from the fluid surface to return. Therefore, the installation is simple and easy to maintain. The object to be measured in the tube can be used for liquids, powders and solids and can measure up to 50M. Various types of water level meters are located at the top of the inside of the upper wall of the sewer pipe, and are installed using a box made of waterproof inside the sewer pipe or inside the concrete wall.

Fig. 3 is a tonometer designed / manufactured to simultaneously measure the hydraulic pressure of the fluid and the pressure of the sediment. The vibration expression pressure measuring system using bellows according to the present invention is connected to the high-pressure pipe when the bellows is directly pressurized by any force on the bellows surface, so that the bellows inner glycol cell is connected. This is indicated by the pressure value at the pressure sensor at one end. The earth pressure gauge can be used for liquid, powder, and solid, and in the present invention, it can be measured up to about 1.0 kg / cm 2 in consideration of the internal diameter of the sewer pipe. This is equivalent to about 10 m in terms of sewer pipe height.

Therefore, the structure to be inserted into the wall of the sewer pipe into which the measuring device with the sensors embedded therein is made of steel or plastic material in the form of a box, and the measuring structure is made waterproof to protect the measuring device. It is manufactured in a structure that protects against the damage, facilitates measurement and installation, and increases the durability of the measuring instrument. In addition, the meter protection box is provided with power and communication ports inside and outside the sewer pipe to transmit measured data to the outside. It is designed / manufactured to increase the flexibility of the transmission system by transmitting the measured values of the height of the soil, etc. to the central control computer to facilitate monitoring of sewer pipes, and to allow the sewage pipes to be selectively transmitted externally or internally. .

The following relevant calculations are sediment height, flow height and flow rate measurement. In general, the specific gravity of the fluid and accumulated sediment flowing in the sewer pipe is as follows.

Specific gravity of the sediment (dreg sewage sludge) (Dd) = about 1.5

Sewage water specific gravity (Sd) = about 1.1

The pressure applied to the earth pressure gauge located in the lower part of the sewer pipe is determined by the level and specific gravity of the fluid flowing in the sewer pipe, and the height and specific gravity of the sediment. Considering this, the pressure applied to the earth pressure gauge is as follows.

Here, the display pressure of the earth pressure gauge is a case where the pressure on the ground surface, which is the standard altitude, is expressed as 0, which indicates the pressure excluding the standard atmospheric pressure. The calculation process will be derived based on the displayed pressure of the pressure gauge which does not include the standard atmospheric pressure, and the head pressure of the pressure gauge 1 kg / ㎠ is converted into approximately 10 m.

Earth pressure (P) = dreg sludge pressure + sewage water pressure

= (Dd * Sediment Height (Dm) + Sd * Sewage Height (Sm)) / 10 (1)

In addition, the height of the sewage measured by the water gauge can be expressed as follows.

Water Level Height (Tm) = Sediment Height (Dm) + Sewage Height (Sm) (2)

The measured pressure can be converted to the height in consideration of the specific gravity of the sediment and sewage, it can be used to calculate the actual sediment height. The calculated sediment height and actual sewage height are given by equations (3) and (4).

Actual dr sludge height (m)

= (10 * P (kg / ㎠)-Sd * Tm (m)) / (Dd-Sd) (3)

Actual sewage water height (m)

= (Dd * Tm (m)-10 * P (kg / ㎠)) / (Dd-Sd) (4)

Can be displayed as

The height of the sediment and the height of the sewage of the equations (3) and (4) can be used to derive the height of the actual sediment using the pressure of the earth pressure gauge and the height of the water gauge measured in the equations (1) and (2). In addition, the fluid level flowing in the actual sewer pipe can also be calculated with relative accuracy.

A very important factor in determining dredging timing in sewer pipes is sediment height.

The actual flow rate into the sewer pipe can be expressed as shown in equation (5).

Actual sewage water flow rate = flow rate * actual sewage height * square sewer pipe width

(5)

There are two types of cross-sections of sewer pipes, which consist of a rectangular box shape and a circular shape. The cross-sectional size of the sewer pipe can be expressed as

Square box type sewer pipe width: W (m)

Radius of circular sewer pipes: R (m)

The flow rate obtained from the tachometer can be expressed as follows.

Flow rate obtained from the tachometer: S (m / min)

Equation (6) is a formula for measuring the flow rate of the rectangular box type sewer pipe using the actual sewer level relational expression obtained from the terms defined above.

Flow rate of square box sewer pipe (㎥ / min)

= Actual sewage water height (m) * sewer pipe width (m) * flow rate (m / min)

= (Dd * Tm (m)-10 * P (kg / ㎠)) / (Dd-Sd) * W (m) * S (m / min)

(6)

Equation (7) is a formula representing the actual sewage flow rate in a circular sewer pipe using the terms defined above. The actual sewer area of the circular sewer pipe can be represented by the cross-sectional area of the sewer system using the height measured by the water level, except for the sediment cross-sectional area.

Flow rate of circular sewer pipes (㎥ / min)

= (Water level height cross section (㎡)-Sediment height cross section (㎡)) * Flow rate (m / min)

(7)

In Equation (7), it can be calculated by dividing the measured value of the water gauge or the sediment into a case where the height is less than the radius (R) of the circular tube and a large case.

If the radius is less than the height of the sewage or sediment measured value (H), the cross-sectional area can be expressed as in Equation (8).

Cross-section = arcCOS [(R-H) / R] * 2/360 * R * R * PI (3.14)

SIN [arcCOS [(R-H) / R]] * R * (R-H) (8)

If the radius is larger than the height of sewage or sediment measured value (H), the cross-sectional area can be expressed as shown in Eq. (9).

Cross-sectional area = (1-arcCOS [(H-R) / R] * 2/360) * R * R * PI (3.14)

+ SIN [arcCOS [(H-R) / R]] * R * (H-R) (9)

Therefore, even in the case of a circular pipe, the flow rate of the fluid is calculated by considering the relationship between the diameter of the sewer pipe, the height measured by the level gauge, and the calculated sediment height according to the above formulas (7), (8) and (9). Able to know.

EXAMPLES

Looking at the specific embodiment according to the present invention by substituting a virtual value, the sewer pipe is mainly used in the passage of the circular and rectangular cross section. However, the shape of the sewage pipes made has a certain size. That is, since the cross-sectional area of the manufactured sewer pipe is known from the time of design / manufacturing, the flow rate of the flowing fluid can be accurately measured by measuring the height of the sediment and the flowing fluid.

Dreg sludge specific gravity (Dd) = about 1.5

Sewage water specific gravity (Sd) = about 1.1

The pressure applied to the seismograph located below the sewer pipe is determined by the sewer pipe level and specific gravity, and the sediment height and specific gravity. Here, the display pressure of the earth pressure gauge is a case where the pressure on the ground surface, which is the standard altitude, is expressed as 0, which indicates the pressure excluding the standard atmospheric pressure. The calculation process will be derived based on the displayed pressure of the pressure gauge which does not include the standard atmospheric pressure, and the head pressure of the pressure gauge 1 kg / ㎠ is converted into approximately 10 m. Considering this, the magnitude of the pressure applied to the earth pressure gauge is shown in Equation (10).

Earth pressure gauge = dreg sludge pressure + sewage water pressure

= (1.5 * sediment height + 1.1 * sewage height) / 10 (10)

The measured pressure can be converted into height by Equation (3), and it can be calculated as the actual sediment height. Equations (11) and (12) are equations representing the height of sediment and the actual sewage converted when the value shown on the hydraulic pressure gauge is 1 kg / cm 2 and the value measured on the water gauge is about 8 m.

Actual dr sludge height (m)

= (10 * pressure gauge (kg / ㎠)-1.1 * level gauge height (m)) / (1.5-1.1)

= 3.0 m (11)

Actual sewage water height (m)

= (1.5 * level gauge height (m)-10 * earth pressure gauge (kg / ㎠)) / (1.5-1.1)

= 5.0 m (12)

This is based on the water level and pressure measured by the water gauge and the earth pressure gauge located in the sewer pipe, and the height of the actual sediment (Eq. (11)) and the actual sewage height (Eq. (12)) using equations (3) and (4). Can be calculated In sewer pipelines, sediment height is a very important factor in determining dredging time. When calculated using the above equations (3) and (4), it is possible to know the height of the fluid flowing in the actual pipe and the height of the sediment relatively accurately.

1) In a box-type pipeline, the pressure gauge is 1 kg / cm 2, the water gauge measures about 8 m, the square box sewer pipe is 5 m wide, and the fluid flow rate is 3 m / min, the actual sewage height 5.0 m can be easily obtained by the above formula. In addition, the actual sewage flow rate flowing into the rectangular sewer pipe by equation (5) is calculated by equation (13).

Actual sewage water flow rate = flow rate * actual sewage height * square sewer pipe width

Actual sewage flow rate: 75 ㎥ / min = 3m / min * 5.0 m * 5m (13)

2) In the box-type pipeline, the pressure gauge value is 1 kg / ㎠, the water level measurement is about 8 m, the radius R of the circular sewer pipe is 5 m, and the flow velocity of the fluid is 3 m / min. In the case of Equation 12, the actual sewage height of 5.0 m, the height of the sediment can be easily obtained by 3.0 m by the formula (11).

In addition, since the actual measured height is larger than the radius of the circular sewer pipe, the cross-sectional area of the height measured by the water gauge in the circular sewer pipe by Equation (9) is calculated by Equation (14).

Cross-sectional area measured with water level = (1-arcCOS [(8-5) / 5] * 2/360) * 5 * 5 * 3.14

+ SIN [arcCOS [(8-5) / 5]] * 5 * (8-5) = 67.33 ㎡

(14)

In addition, since the actual calculated sediment height is smaller than the radius of the circular sewer pipe, the cross-sectional area of the sediment height deposited in the circular sewer pipe by Eq. (8) is calculated by Eq. (15).

Sediment cross section = arcCOS [(5-3) / 5] * 2/360 * 5 * 5 * 3.14

SIN [arcCOS [(5-3) / 5]] * 5 * (5-3) = 19.8 m 2 (15)

Therefore, the actual sewage flow rate flowing through the circular sewer pipe is calculated by equation (16).

Actual sewage water flow rate = flow rate * (cross section measured by water gauge-sediment cross section)

Actual sewage flow rate: 142.59 ㎥ / min = 3m / min * (67.33 ㎡-19.8 ㎡) (16)

The values measured by the tachometer, water gauge and earth pressure gauge are transmitted externally to calculate the height of the actual sediment (Eq. (11)), the actual sewage height and the actual sewage water flow rate by computer and use them. The maintenance and monitoring system of the entire sewer line is operated. Since the connection part for data transmission is buried underground under the same conditions as underwater, the structure is designed / manufactured with durability to maintain the function even under waterproof and earth pressure. The transmission method for transmitting the measurement value is a method commonly used to connect the precise sewerage measurement system in which measurement values are transmitted to a modem, which is a conventional general data transmission method using a small computer. Was adopted.

The central control system controls the height of the actual sediment (Equation (11)), the actual sewage height and the actual sewage water flow rate, etc. calculated using the data inputted from the sensors installed at the various places and the input data. It can be stored in the database in memory and the monthly or yearly changes and necessary data can be printed and viewed on a monitor or printer as needed.

The flowmeter, water gauge, and earth pressure gauge may be used by selecting another type of flow meter or earth pressure gauge. In addition to the present invention, the existing DO meter surface scattering light measurement turbidimeter, glass electrode method (composite glass electrode) PH meter, neutralization-type alkalimeter, AC two-electrode conductivity meter, polarograph residual When chlorine measuring device, UV absorption type, UV ray 254nm / visible ray organic measuring automatic measuring device and infrared ray scattering light SS meter are installed together with necessary sensors as needed, Information can be obtained and the obtained information is stored in a database on the memory of the central control system so that the change in the degree of contamination inside the sewer pipe and the current degree of contamination can always be checked on a computer monitor.

The precision sewage sediment height and flow measurement system according to the present invention is designed / manufactured in a suitable structure and size so that most sediment heights and flow rates can be effectively measured in all types of sewage pipelines. By installing and using the water level measurement system, it is possible to measure the flow rate of sewage pipes by the lower sediment more quickly and accurately. In addition, it is possible to more accurately measure the flow rate of the sewage pipe according to the type of sewage, which is slightly different depending on the season, by using the sediment density according to the type of deposit.

It is possible to know the actual sediment height by calculating the pressure measured by the earth pressure gauge in terms of the water level measured by the existing level gauge.

It is possible to monitor the flow rate, flow rate, and sediment volume in the current and past sewage pipelines by section, and objectively know the inflow and outflow of sewage by section or time, and information about the flow rate and rainfall in the sewer pipe It is effective to monitor the monitoring and analysis in real time, and by acquiring accurate measurement of this essential information, it is possible to determine the time and location of dredging pipeline, calculate the maximum treatment capacity of sewage pipe, and optimize the operation of sewage terminal treatment plant. It works.

Claims (6)

In the precision sewer flow measurement system that accurately measures the height and flow rate of the optimum water in the sewer pipe, A torometer capable of simultaneously measuring the pressure and water pressure of the precipitate; A water level meter and a flow rate meter which can measure the water level and the flow rate, Means for calculating the actual sediment height and the actual sewage height inside the sewer pipe using the values measured from the earth pressure gauge, water gauge and flow meter; A memory for storing the values detected by the earth pressure gauge, water gauge and flow meter, the actual sediment height calculated from these values, and the height of the actual sewage; Measurement of the height and flow rate of sewage sediment consisting of a tonometer, a flow meter and a water level meter, characterized in that it has a display panel or a printer capable of displaying the values obtained by the sensors and various data stored in the memory so as to be visible when necessary. system. The method according to claim 1, The means for calculating the height of the actual sediment and the actual sewage is made of a tonometer, flowmeter and water gauge characterized by more accurate measurement by applying different calculation methods according to the type of soil and sewage and pipe structure. System for measuring the height and flow of sewage sediment. The method according to claim 1 or 2, The earth pressure gauge is a sewage sediment height and flow rate measuring system consisting of a earth pressure gauge, a flow meter and a water level gauge, characterized in that fixed to be located at the center lower or lowermost on the sewer pipe structure. The method according to claim 1 or 2, The water gauge and the flow meter is a sewage sediment height and flow rate measurement system consisting of a seismograph, a flow meter and a water gauge, characterized in that fixed to be located inside or on the top of the sewer pipe structure. The method according to claim 1 or 2, The memory storing the various data is systematically separated by time or interval by separating the height of the actual sediment and the height of the actual sewage calculated by the data obtained from the various types of sensors and the data obtained by the sensors. A sewage sediment height and flow rate measurement system comprising a torometer, a flow meter and a water gauge, characterized in that it has a means stored in the. The method according to claim 5, Means for transmitting the data obtained from the various sensors in real time to the central control unit is a modem (MODEM) characterized in that the sewer sediment height and flow rate measurement system consisting of a tonometer, a flow meter and a water gauge.