On-line continuous sampling and detecting device for fluid in vertical non-pressure self-flowing pipeline

Abstract

The utility model relates to the field of fluid sampling detection, in particular to an on-line continuous sampling detection device for fluid in a vertical non-pressure self-flowing pipeline, which comprises a sampling groove, a liquid guide pipe, a sampling valve, an exhaust pipe, a floating cylinder, a flow cell, a liquid discharge pipe, a sensor and a display meter which are connected in sequence. The sampling groove is a semicircular flow groove with an open upper part and extends upwards to the middle part of the pipeline, and the groove surface faces the water falling direction, so that continuous and stable fluid sampling is realized; the ratio of the pipe diameter of the floating cylinder to the pipe diameter of the liquid guide pipe is (1.5-2.5): 1; the flow speed of the fluid in the floating cylinder is slow, bubbles in the fluid are gathered and enlarged and are gradually separated from the liquid, and the separated bubbles are discharged through the exhaust pipe; according to the utility model, accurate and continuous sampling can be realized in a complex and unstable fluid state, and the interference of bubbles in a sample on a measurement result can be effectively eliminated.

Description

Technical Field

[0001] The utility model belongs to the field of fluid sampling and detection, and in particular relates to an online continuous sampling and detection device for fluid in a vertical pressure-free gravity pipeline. Background Art

[0002] In the water treatment and environmental monitoring industries, fluid sampling and testing is a critical water quality assessment tool and is crucial for measuring water quality. Accurate sampling and measurement results not only rely on advanced analytical sensor technology but are also closely related to sample collection procedures. In practice, the inventors faced two distinct pipeline conditions: the common, relatively simple, pressurized pipeline sampling; and the more rare, vertical, unpressurized, gravity-fed pipeline sampling, which is more challenging.

[0003] In vertical, unpressurized, gravity-fed pipelines, effective and continuous sampling is difficult, especially when gas-liquid two-phase flow and flow patterns are unstable. Furthermore, samples are often contaminated with bubbles. Once a bubble-laden sample passes through an online analytical sensor, the bubbles can adhere to or float around the sensor probe, causing the measurement results to deviate from normal values and introduce errors. This error can mislead operators into making incorrect decisions, leading to deviations from the intended production process and, in severe cases, significant economic losses.

[0004] Therefore, how to achieve accurate and continuous sampling under complex and unstable fluid conditions, and effectively eliminate the interference of bubbles in the sample on the measurement results, is an urgent issue to be overcome in the field of fluid sampling and detection. Summary of the Invention

[0005] The purpose of the present invention is to provide an online continuous sampling and detection device for fluid in a vertical pressure-free self-flowing pipeline, which can realize effective and continuous sampling in a vertical pressure-free self-flowing pipeline environment, eliminate bubbles in the sample, and reduce detection errors.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The present invention provides an online continuous sampling and detection device for fluid in a vertical pressure-free gravity pipe, comprising a vertical pressure-free gravity pipe, a sensor and a display meter, as well as a sampling trough and a liquid guide tube. The sampling trough is arranged inside the gravity pipe and extends upwardly and obliquely to the middle of the pipe. The sampling trough is a flow trough with an open top, and the trough surface faces the direction of falling water. The root of the sampling trough passes through the pipe wall of the gravity pipe and is connected to the liquid guide tube. The outer end of the liquid guide tube is connected to a sampling valve, and the outer end of the sampling valve is connected to the lower end of an exhaust pipe through a pipe. The lower end of the exhaust pipe is connected to an air float. The exhaust pipe and the air float are vertically arranged and are connected to the sampling valve in a three-way manner. The lower end of the air float is connected to a circulation pool through a pipe. The circulation pool is also provided with a drain pipe, and the drain pipe is an inverted U-shaped structure for maintaining the liquid level in the circulation pool. The sensor is arranged in the circulation pool and electrically connected to the display meter.

[0008] Preferably, the sampling trough is a semicircular flow trough with an open top.

[0009] Preferably, the ratio of the diameter of the float cylinder to the diameter of the liquid guiding tube is 1.5-2.5:1; the function of the float cylinder is to slow down the sample flow rate, prolong the residence time of the sample in the float cylinder, and allow sufficient time for gas-liquid separation of the gas mixed in the sample.

[0010] Preferably, the height of the inverted U-shaped top of the drainage pipe is higher than the bottom height of the sensor; first, the sample liquid level in the circulation pool is submerged above the detection probe to ensure the accuracy of the detection; second, when the process is stopped or the sampling valve is closed, the sample liquid level in the circulation pool is ensured to be submerged above the detection probe to protect the detection probe.

[0011] Preferably, the height of the air outlet at the top of the exhaust pipe is higher than the height of the upper end of the sampling tank; the function is to prevent the sample from overflowing from the exhaust pipe when the sample flow rate in the float cylinder is too slow.

[0012] Preferably, a short tube is further provided on the outside of the liquid guide tube, one end of the short tube is fixed to the outer wall of the pipeline, and the other end is sealed by a flange. The liquid guide tube passes through the short tube and the flange and is connected to the sampling valve; it is convenient to install and disassemble the sampling device.

[0013] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0014] (1) The fluid on the cross section of a vertical non-pressure gravity-fed pipe is mainly distributed in a ring shape, that is, the fluid distribution characteristics on both sides of the center line of the pipe are similar, and the fluid distribution on one side is uneven. According to its distribution characteristics, a sampling slot is set along the radial direction of the pipe cross section at the sampling port, and the sampling slot is facing the direction of water drop, with the top extending to the middle of the pipe. The sampling slot has a larger area than the sampling port, ensuring the continuous and stable sampling of fluid samples under the condition of uneven fluid distribution; under the action of gravity, the fluid sample enters the inclined sampling slot, and under the blocking action of the sampling slot, the fluid is adjusted from vertical flow to flow along the pipe direction, ensuring that the sample has the power to continue to flow in the liquid guide tube and subsequent pipe fittings.

[0015] (2) The ratio of the diameter of the float cylinder to the diameter of the liquid guide tube is 1.5-2.5:1; the fluid flows slowly in the float cylinder, which is conducive to the accumulation and upward movement of bubbles. When the fluid sample enters the float cylinder, the flow rate slows down, the bubbles gather and grow larger, and gradually separate from the liquid. The separated bubbles are discharged through the exhaust pipe. In this way, the gas mixed in the sample can be easily discharged, preventing the bubbles from affecting the test results.

[0016] (3) Through the combination of some simple materials, continuous sampling and sample pretreatment are achieved on the vertical pressure-free gravity pipeline. The relevant chemical properties of the samples do not change during the treatment process, and the original state of the process medium is fully restored. Accurate fluid sampling and measurement are achieved, which prevents operators from misjudging the process operation status due to inaccurate test results, resulting in unnecessary process adjustments and economic losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the utility model

[0018] Figure 2 Front view of the sampling unit

[0019] Figure 3 Top view of the sampling unit

[0020] Figure: 1. Vertical pressure-free gravity pipe 2. Sampling trough 3. Liquid guide tube 4. Short pipe 5. Sampling valve 6. Exhaust pipe 7. Air cylinder 8. Circulation pool 9. Drain pipe 10. Sensor 11. Display 12. Flange DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to the accompanying drawings and implementation examples.

[0022] like Figure 1-3As shown, the present invention provides an online continuous sampling and detection device for fluid in a vertical non-pressure gravity pipe, comprising a vertical non-pressure gravity pipe 1 sensor 10 and a display meter 11, characterized in that it also includes a sampling trough 2 and a liquid guide tube 3, the sampling trough 2 is arranged inside the gravity pipe 1, and extends upwardly and obliquely to the middle of the pipe 1, the sampling trough 2 is a flow trough with an open top, and the sampling trough 2 is preferably a semicircular flow trough with an open top, the trough surface facing the direction of falling water, and the root of the sampling trough 2 passes through the wall of the gravity pipe 1 and the liquid guide tube 3. The outer end of the liquid guide tube 3 is connected to a sampling valve 5, which is connected to the lower end of an exhaust pipe 6 via a pipe. The lower end of the exhaust pipe 6 is connected to a float cylinder 7. The exhaust pipe 6 and float cylinder 7 are arranged vertically and connected to the sampling valve 5 in a three-way connection. The lower end of the float cylinder 7 is connected to a circulation pool 8 via a pipe. The circulation pool 8 is also provided with a drain pipe 9, which is an inverted U-shaped structure and is used to maintain the liquid level in the circulation pool 8. A sensor 10 is disposed in the circulation pool 8 and is electrically connected to a display meter 11. The ratio of the diameter of the float cylinder 7 to the diameter of the liquid guide tube 3 is 1.5-2.5:1. The function of the float cylinder 7 is to slow the sample flow rate and prolong the sample's residence time in the float cylinder, allowing sufficient time for gas mixed with the sample to separate from the liquid before being discharged through the exhaust pipe 6. The drainage pipe 9 has an inverted U-shaped structure, with the top of the inverted U-shaped portion being higher than the bottom of the sensor 10. This ensures that the sample level in the circulation pool 8 is submerged above the detection probe, ensuring detection accuracy. Furthermore, when the process is shut down or the sampling valve is closed, the sample level in the circulation pool 8 is submerged above the detection probe, protecting the detection probe. The top outlet of the exhaust pipe 6 is higher than the top of the sampling tank 2. This prevents the sample from overflowing from the exhaust pipe 6 when the sample flow rate in the air cylinder 7 is too slow. A short tube 4 can also be provided on the outside of the liquid guide tube 3. One end of the short tube 4 is fixed to the outer wall of the pipeline 1, and the other end is sealed by a flange 12. The liquid guide tube 3 passes through the short tube 4 and the flange 12 to connect to the sampling valve 5, facilitating installation and removal of the sampling device.

[0023] The following describes the workflow of the above-mentioned online continuous sampling and detection device for fluids in a vertical, pressureless, gravity-fed pipeline, using turbidity detection as an example. When the process medium flows through sampling slot 2, located within vertical, pressureless, gravity-fed pipeline 1, it is accurately captured by sampling slot 2 and flows through liquid conduit 3, sampling valve 5, exhaust pipe 6, and air cylinder 7 into circulation pool 8. Sampling valve 5 regulates the fluid flow rate, and the fluid undergoes gas-liquid separation within vertically mounted air cylinder 7. The separated gas is discharged through upper exhaust pipe 6. Sensor 10, a turbidity sensor, is located within circulation pool 8. It detects the fluid sample within circulation pool 8 and transmits the detection signal to turbidity display meter 11 for display. Once the detection is complete, the sample flows out of the sampling device through discharge pipe 9. Accurate and continuous sampling is achieved under complex and unstable fluid conditions, as well as the effective removal of gas from the sample, ensuring accurate detection of turbidity parameters of the process medium.

[0024] The above description is only a specific embodiment of the present invention, but the structural features protected by the present invention are not limited thereto. Any changes or modifications made by any technician in this field within the scope of the present invention are included in the patent scope of the present invention.

Claims

1. An online continuous sampling and detection device for fluid in a vertical non-pressure gravity-flowing pipe, comprising a vertical non-pressure gravity-flowing pipe (1), a sensor (10) and a display meter (11), characterized in that: The invention also includes a sampling trough (2) and a liquid guide tube (3). The sampling trough (2) is arranged inside the gravity pipe (1) and extends upward to the middle of the pipe (1). The sampling trough (2) is a flow trough with an open top and a trough surface facing the direction of falling water. The root of the sampling trough (2) passes through the wall of the gravity pipe (1) and is connected to the liquid guide tube (3). The outer end of the liquid guide tube (3) is connected to a sampling valve (5). The outer end of the sampling valve (5) is connected to the lower end of the exhaust pipe (6) through a pipe. The exhaust The lower end of the tube (6) is connected to a float cylinder (7), the exhaust pipe (6) and the float cylinder (7) are vertically arranged and are connected to the sampling valve (5) in a three-way manner; the lower end of the float cylinder (7) is connected to a circulation pool (8) through a pipeline, and a drain pipe (9) is also provided on the circulation pool (8), and the drain pipe (9) is an inverted U-shaped structure for maintaining the liquid level in the circulation pool (8); the sensor (10) is arranged in the circulation pool (8) and is electrically connected to the display meter (11).

2. The online continuous sampling and detection device for fluid in a vertical non-pressure gravity-fed pipeline according to claim 1 is characterized in that: The sampling trough (2) is a semicircular flow trough with an open top.

3. The online continuous sampling and detection device for fluid in a vertical non-pressure gravity-fed pipeline according to claim 1 is characterized in that: The ratio of the diameter of the air float cylinder (7) to the diameter of the liquid guide tube (3) is 1.5-2.5:

1.

4. The online continuous sampling and detection device for fluid in a vertical non-pressure gravity-fed pipeline according to claim 1 is characterized in that: The height of the inverted U-shaped top of the liquid discharge pipe (9) is higher than the height of the bottom of the sensor (10).

5. The online continuous sampling and detection device for fluid in a vertical non-pressure gravity-fed pipeline according to claim 1 is characterized in that: The height of the air outlet at the top of the exhaust pipe (6) is higher than the height of the upper end of the sampling tank (2).

6. The online continuous sampling and detection device for fluid in a vertical non-pressure gravity-flowing pipeline according to claim 1 is characterized in that: A short tube (4) is further provided on the outside of the liquid guiding tube (3). One end of the short tube (4) is fixed to the outer wall of the pipeline (1), and the other end is sealed by a flange (12). The liquid guiding tube (3) passes through the short tube (4) and the flange (12) to be connected to the sampling valve (5).

Images