Optical fiber detector for oil pollutants in water pollution

Abstract

The invention provides an optical fiber detector for oil pollutants in water pollution, which belongs to the field of measuring equipment and comprises a sensor, a strain optical fiber, a hydrophobic oleophylic film and an oil-sensitive material. The sensor is a closed hollow assembly with a circular truncated cone at the upper part and a cylinder at the lower part, the side surface of the circular truncated cone is enclosed by a stainless steel gauze, the hydrophobic oleophylic film covers the whole outer surface of the circular truncated cone part of the sensor, so that a closed cavity is formed in the sensor, and the oil-sensitive material is filled in the cavity of the sensor. One end of the strain optical fiber is connected with the optical fiber demodulator, and the other end of the strain optical fiber enters the cavity of the sensor. The device can detect the content of oil pollutants in sewage through the optical fiber, is high in measurement precision, simple in structure, small in size and convenient to carry, and is suitable for grease detection in various occasions. In addition, the type of the hydrophobic oleophylic film can be replaced according to the type of the detected grease, detection of various kinds of grease is achieved, and the sensor can be repeatedly used and is easy to operate and low in cost.

Description

Technical Field

[0001] The invention relates to the field of measuring equipment, in particular to an optical fiber detector for oil pollutants in water pollution. Background Art

[0002] Oily wastewater is a kind of harmful waste that harms the environment. It mainly appears in the treatment process of oily waste residues generated by oil extraction, oil refining, chemical industry and other industries. Sewage contains a large amount of grease and chemicals. If it is not effectively treated, it will cause serious pollution to the soil, water and air. At present, there are some detection devices and methods for the oil content of sewage.

[0003] For example, Chinese invention patent document CN118655289A discloses a device for detecting the oil content in the process of washing oil-containing sludge. After using solvent to emulsify oil to form an oil-water body, centrifugal force is used to separate oil and water to detect the oil content. This method requires the addition of solvent and the use of centrifugal equipment, which is cumbersome to operate and costly.

[0004] Chinese invention patent document CN103528960A discloses an online sewage monitoring system using spectral interferometry, which determines the suspended matter and oil content in water by the changes in interference fringes produced when light waves pass through different water qualities. However, the device is large and difficult to move, and can only be used for sampling and testing.

[0005] Chinese invention patent document CN104316496B discloses a device for monitoring oil and grease pollutants in high-power lasers. By changing the refractive index of the micro-nano optical fiber coating material, the transmission characteristics of the evanescent wave on its surface are affected to meet the monitoring of oil and grease pollutants. However, the device requires a high-power laser to operate, the monitoring cost is high, and there is a certain degree of danger.

[0006] In summary, existing monitoring equipment has problems such as limited application range, high cost, and cumbersome operation. Based on this, the present invention designs an optical fiber detector for oil pollutants in water pollution. Summary of the invention

[0007] The technical problem to be solved by the present invention is the defects of the prior art, and the purpose is to achieve accurate sensing of oil pollutants in water pollution in view of the defects of the prior art.

[0008] In order to achieve the above-mentioned purpose, the present invention intends to adopt the following technical scheme.

[0009] An optical fiber detector for oil pollutants in water pollution, comprising a protective tube, a sensor, a weighing plate, a strain optical fiber, a hydrophobic and oleophilic film, an oil-sensitive material, an electric heating wire and an optical fiber demodulator;

[0010] The protective tube is a hollow cylinder composed of stainless steel mesh and including upper and lower end surfaces; the sensor is a closed hollow combination of an upper truncated cone and a lower cylinder, wherein the cylindrical part is composed of a stainless steel plate, the upper end surface of the truncated cone is a stainless steel plate, and the side surface is surrounded by a stainless steel mesh; the hydrophobic and oleophilic membrane covers and is fixedly connected to the entire outer surface of the truncated cone of the sensor, so that a closed cavity is formed inside the sensor; the protective tube and the sensor are coaxial, the protective tube is sleeved on the outside of the sensor, and the upper and lower bottom surfaces of the two are welded together;

[0011] The weighing plate is placed on the top of the cylinder of the sensor, and the oil-sensitive material fills the cavity of the sensor; n+1 lead holes are respectively opened on the top surface of the sensor, one of which is located at the center of the sensor, and the other n lead holes are evenly distributed around the center of the sensor; one end of the strain optical fiber is connected to the optical fiber demodulator, and the other end enters the cavity of the sensor through the lead hole located at the center of the top surface of the sensor, and is connected to the upper surface of the weighing plate; there are n electric heating wires, one end of the n electric heating wires is connected to a power source, and the other end enters the cavity of the sensor through other lead holes and is connected to the upper surface of the weighing plate.

[0012] Preferably, a ventilation hole is provided on the top surface of the sensor.

[0013] Preferably, the outer diameter of the weighing pan is 0.1 mm smaller than the inner diameter of the lower cylinder of the sensor, and can be axially retracted in the lower cylinder of the sensor.

[0014] Preferably, the contact point between the optical fiber and the lead-in hole, and the contact point between the electric heating wire and the lead-in hole are both sealed with sealing materials.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The present invention designs an optical fiber detector for oil pollutants in water pollution, which detects the content of oil pollutants in sewage through optical fiber with high measurement accuracy.

[0017] (2) The present invention has a simple structure, a small size, is easy to carry, and is suitable for oil and fat detection in various occasions.

[0018] (3) The present invention can replace the type of hydrophobic and oleophilic membranes according to the type of grease to be detected, thereby realizing various grease detections. The sensor is reusable, simple to operate, and low in cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the structure of the optical fiber detector for oil pollutants in an embodiment of the present invention.

[0020] Figure 2 Schematic diagram of the sensor structure in an embodiment of the present invention.

[0021] Figure 3 This is an enlarged schematic diagram of the location of the lead-in hole and the air guide hole.

[0022] Figure numerals: 1. protective tube; 2. sensor; 3. weighing plate; 4. strain optical fiber; 5. hydrophobic and oleophilic film; 6. oil-sensitive material; 7. electric heating wire; 8. air guide hole; 9. lead hole. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0024] Figure 1 Schematic diagram of the structure of the optical fiber detector for oil pollutants in an embodiment of the present invention. Figure 2 is a schematic diagram of the sensor structure in an embodiment of the present invention, Figure 3 This is an enlarged schematic diagram of the location of the lead-in hole and the air guide hole.

[0025] As can be seen from the above drawings, the present invention provides an optical fiber detector for oil pollutants in water pollution, including a sheath 1, a sensor 2, a weighing plate 3, a strain optical fiber 4, a hydrophobic and oleophilic film 5, an oil-sensitive material 6, an electric heating wire 7 and an optical fiber demodulator.

[0026] The casing 1 is a hollow cylinder composed of stainless steel mesh and includes upper and lower end surfaces. The sensor 2 is a closed hollow combination of an upper truncated cone and a lower cylinder, wherein the cylindrical part is composed of a stainless steel plate, the upper end surface of the truncated cone is a stainless steel plate, and the side surface is surrounded by a stainless steel mesh. The hydrophobic and oleophilic membrane 5 covers and is fixed to the entire outer surface of the truncated cone of the sensor 2, so that a closed cavity is formed inside the sensor 2. The casing 1 and the sensor 2 are coaxial, and the casing 1 is sleeved on the outside of the sensor 2, and the upper and lower bottom surfaces of the two are welded together.

[0027] The weighing plate 3 is placed on the top of the cylinder of the sensor 2, and the oil-sensitive material 6 fills the cavity of the sensor 2. The top surface of the sensor 2 is provided with n+1 lead holes 9, one of which is located at the center of the sensor 2, and the other n lead holes 9 are evenly distributed around the center of the sensor 2. One end of the strain optical fiber 4 is connected to the optical fiber demodulator, and the other end enters the cavity of the sensor 2 through the lead hole 9 located at the center of the top surface of the sensor 2, and is connected to the upper surface of the weighing plate 3. There are n electric heating wires 7, one end of each of the n electric heating wires 7 is connected to a power source, and the other end enters the cavity of the sensor 2 through other lead holes 9, and is connected to the upper surface of the weighing plate 3.

[0028] In this embodiment, a ventilation hole 8 is further provided on the top surface of the sensor 2 .

[0029] In this embodiment, the outer diameter of the weighing plate 3 is 0.1 mm smaller than the inner diameter of the lower cylinder of the sensor 2 , and the weighing plate 3 can be axially retracted in the lower cylinder of the sensor 2 .

[0030] In this embodiment, the contact portion between the optical fiber 4 and the lead-in hole 9 and the contact portion between the electric heating wire 7 and the lead-in hole 9 are both sealed with sealing materials.

[0031] In this embodiment, n=2, and the distance between the two electric heating wires 7 and the strain optical fiber 4 is 1 cm. The heating wires 7 are connected to a power source to heat and remove moisture in the cavity of the sensor 2 .

[0032] In this embodiment, the hydrophobic and oleophilic membranes 5 can be selectively replaced according to the type of grease to be detected.

[0033] In this embodiment, the function of the casing 1 is to block various objects in the water for the sensor 2 and protect the sensor 2 from erosion.

[0034] In this embodiment, the measurement of different sewage depths can be achieved by adjusting the length of the strain optical fiber 4, and the maximum measurement depth is 100 meters.

[0035] In this embodiment, the hydrophobic and oleophilic membrane 5 plays a role in isolating water and allowing oil to pass, so that oil pollutants can more easily enter the interior of the sensor 2 .

[0036] In this embodiment, the oil-sensitive material 6 functions to absorb oil pollutants.

[0037] In this embodiment, the weighing pan 3 is made of stainless steel to prevent oxidation caused by long-term immersion in water and cause measurement errors.

[0038] In this embodiment, the device of the present invention can be placed in sewage for a long time to achieve long-term in-situ real-time monitoring of oil pollutants in water pollution.

Claims

1. An optical fiber detector for oil pollutants in water pollution, characterized in that: It comprises a protective sleeve (1), a sensor (2), a weighing plate (3), a strain optical fiber (4), a hydrophobic and oleophilic film (5), an oil-sensitive material (6), an electric heating wire (7) and an optical fiber demodulator; The protective tube (1) is a hollow cylinder including upper and lower end surfaces made of stainless steel mesh; the sensor (2) is a closed hollow combination of an upper truncated cone and a lower cylinder, wherein the cylindrical part is made of a stainless steel plate, the upper end surface of the truncated cone is a stainless steel plate, and the side surface is surrounded by a stainless steel mesh; the hydrophobic and oleophilic membrane (5) covers and is fixedly connected to the entire outer surface of the truncated cone of the sensor (2), so that a closed cavity is formed inside the sensor (2); the protective tube (1) and the sensor (2) are coaxial, the protective tube (1) is sleeved on the outside of the sensor (2), and the upper and lower bottom surfaces of the two are welded together; The weighing plate (3) is placed on the top of the cylinder of the sensor (2), and the oil-sensitive material (6) fills the cavity of the sensor (2); n+1 lead holes (9) are respectively opened on the top surface of the sensor (2), one of which is located at the center of the sensor (2), and the other n lead holes (9) are evenly distributed around the center of the sensor (2); one end of the strain optical fiber (4) is connected to the optical fiber demodulator, and the other end enters the cavity of the sensor (2) through the lead hole (9) located at the center of the top surface of the sensor (2) and is connected to the upper surface of the weighing plate (3); there are n electric heating wires (7), one end of each of the n electric heating wires (7) is connected to a power source, and the other end enters the cavity of the sensor (2) through the other lead holes (9) and is connected to the upper surface of the weighing plate (3).

2. The optical fiber detector for oil pollutants in water pollution according to claim 1, characterized in that: The top surface of the sensor (2) is also provided with a ventilation hole (8).

3. The optical fiber detector for oil pollutants in water pollution according to claim 1, characterized in that: The outer diameter of the weighing plate (3) is 0.1 mm smaller than the inner diameter of the lower cylinder of the sensor (2), and can be axially retracted within the lower cylinder of the sensor (2).

4. The optical fiber detector for oil pollutants in water pollution according to claim 1, characterized in that: The contact point between the optical fiber (4) and the lead-in hole (9), and the contact point between the electric heating wire (7) and the lead-in hole (9) are both sealed with sealing materials.

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