An online monitoring device and method for multiple oil content in water based on oil type determination

Abstract

This invention proposes an online monitoring device and method for the content of multiple oil types in water based on oil type identification. The invention includes a housing, a light source assembly, a light source monitoring detector, a fluorescence monitoring assembly, and a control circuit board. The housing is a sealed housing, equipped with a temperature sensor and a watertight connector. The light source assembly is positioned on the axis of the housing and has multiple excitation light sources. The light source monitoring detector is tilted to one side of the light source assembly and connected to the light source assembly via an optical channel. Multiple fluorescence monitoring components are evenly distributed around the circumference of the light source assembly and are tilted. The control circuit board is located inside the housing, and the light source assembly, light source monitoring detector, fluorescence monitoring assembly, and temperature sensor are all connected to the control circuit board. The control circuit board is connected to a host computer via a watertight connector. This invention determines the oiliness of unknown oil types in the water body under test, achieving high accuracy and wide applicability in determining the content of unknown oil types.

Description

Technical Field

[0001] The present invention relates to the technical field of oil monitoring in water, and in particular to an online monitoring device and method for multiple oil content in water based on oil type determination. Background Art

[0002] Petroleum and its products enter the aquatic environment during the processes of extraction, refining, storage, transportation and use. For example, oily wastewater from refineries is injected into the ocean through rivers or directly; oil tankers leak, discharge or accidents cause oil products to enter the ocean directly; oil spills and blowouts in submarine oil fields during the extraction process cause oil to enter the ocean water; and local natural oil spills in the ocean bottom.

[0003] For application scenarios such as tracking and monitoring of oil spills, monitoring of pollution discharge in offshore oil exploration and development, and real-time monitoring of ship desulfurization washing water discharge, laboratory analysis methods are usually used to determine the content of petroleum pollutants in water bodies. This monitoring method collects samples on site and then sends them to the laboratory for monitoring. During the process of sending the water body for inspection, the water body is static. When the water body is left for too long, physical and chemical changes such as sedimentation and dissolution are prone to occur, causing the samples to be unstable, thus affecting the validity of the monitoring data; moreover, the testing process of this detection method is time-consuming and cannot achieve real-time control. Summary of the invention

[0004] The purpose of the present invention is to provide an online monitoring device and method for multiple oil types in water based on oil type determination, aiming to solve the problems that the monitoring method of petroleum pollutant content in water in the prior art cannot achieve real-time monitoring, resulting in a long time consumption, inconvenient monitoring and poor effectiveness of monitoring data.

[0005] In order to solve the above technical problems, the technical solution of the present invention is achieved as follows:

[0006] In one aspect, the present invention provides an online monitoring device for multiple oil types in water based on oil type determination, comprising a shell, a light source assembly, a light source monitoring detector, a fluorescence monitoring assembly and a control circuit board; the shell is a sealed shell, a first end of the shell is provided with a temperature sensor, the temperature sensor is used to measure the temperature of the water body to be measured, and the second end of the shell is provided with a watertight joint; the light source assembly is arranged at the first end of the shell and is located on the axis of the shell, a plurality of excitation light sources are arranged on the light source assembly, and the excitation light sources are used to emit ultraviolet light and irradiate it into the water body to be measured; the light source monitoring detector is arranged at the first end of the shell and Located on one side of the light source assembly, the light source monitoring detector is tilted and connected to the light source assembly through an optical channel; the fluorescence monitoring components are also arranged in a plurality at the first end of the shell and are evenly distributed around the light source assembly, and the fluorescence monitoring components are tilted to receive the fluorescence generated by the oil in the water to be tested being irradiated with ultraviolet light; the control circuit board is arranged inside the shell, and the light source assembly, the light source monitoring detector, the fluorescence monitoring assembly and the temperature sensor are all connected to the control circuit board, and the control circuit board is connected to a host computer through the watertight joint.

[0007] The present invention has multiple excitation light sources and multiple fluorescence monitoring components. Since the content of aromatic compounds in crude oil and natural gas in water affects the fluorescence intensity, different regions and different oil and gas sources have their own characteristics, and the fluorescence spectra also have their own characteristics, which lays the foundation for the identification of oil species. The present invention can determine the oiliness of unknown oil species in the water to be tested, and realizes the corresponding determination of the content of unknown oil species. It can not only determine the content of light oil, but also determine the content of medium oil and heavy oil, and realizes the determination of the content of different types of oil species in water. The control circuit board is used to control the opening and closing of the light source component, the light source monitoring detector and the fluorescence monitoring component, the calculation of the oiliness index, the collection and calculation of the fluorescence signal, the light source intensity fluctuation signal and the temperature signal to obtain the concentration of the oil species in the water. The temperature is measured and transmitted to the host computer. Under the action of the light source monitoring detector, temperature sensor and control circuit board, the compensation of light source intensity and temperature in the process of oil content determination is realized, the influence of environmental factors such as light source intensity and temperature is eliminated, the detection accuracy is improved, the measurement result is accurate and reliable, and the real-time online monitoring of unknown oil content in water is realized. It can be used for monitoring the oil content in water during pollutant discharge and detecting the type of oil in water during oil exploration and development. It has a wide range of applications and can be used for tracking and monitoring of oil spill accidents, monitoring of sewage discharge in marine oil exploration and development, and real-time monitoring of ship desulfurization washing water discharge. It can accurately discover the nature of oil in oil exploration and development; it has simple structure, small size, low cost, low power consumption and high monitoring accuracy.

[0008] As a preferred embodiment, the majority of the excitation light sources are arranged on a mounting seat, and the majority of the excitation light sources are distributed in a circular array on the mounting seat with the axis of the shell as the center line. The majority of the excitation light sources arranged on the mounting seat form a light source assembly, and the upper computer controls the excitation light sources on the light source assembly to turn off or on through the control circuit board; the selection of the excitation light source is determined according to the type of oil, and multiple excitation light sources can be selected at any time, which is convenient to use.

[0009] As a preferred embodiment, the excitation light source is an LED, and there are three LEDs, and the central wavelengths of the three LEDs are 254nm, 320nm, and 360nm respectively. The three LEDs can meet the determination of the content of different types of oils, and the LED with the corresponding wavelength is selected according to the oiliness of the oil.

[0010] As a preferred embodiment, the fluorescence monitoring component includes a photodetector and a filter disposed at the front end of the photodetector. The photodetector receives the fixed wavelength fluorescence generated by the ultraviolet light irradiation of the petroleum pollutants (also called oil products, which are unknown oil species) in the water body to be tested through the filter control, and then performs photoelectric conversion through the photodetector to convert it into the value of the fluorescence intensity of the oil species in the water body to be tested. The fluorescence intensity in the water body is linearly related to the oil species content in the water body, and then the value of the oil species concentration in the water body is calculated and displayed in the host computer.

[0011] As a preferred embodiment, there are three fluorescence monitoring components, and the central wavelengths of the three filters are 320nm, 360nm, and 460nm, respectively, and the bandwidth is 10nm. The wavelengths that can be passed by the three filters are 310-330nm, 350-370nm, and 450-470nm, respectively. The three filters can be selectively applied to match different types of oil, thereby accurately measuring the content of unknown oil.

[0012] As a preferred embodiment, a first mounting groove is provided at the first end of the housing, the light source assembly is arranged in the first mounting groove, and a first light-transmitting glass sheet is provided at the top of the first mounting groove. The center line of the first mounting groove is in the same straight line as the axis of the housing, and the arrangement of the first mounting groove facilitates the installation of the light source assembly; the first light-transmitting glass sheet is a high-light-transmitting glass, also known as a high-light-transmitting optical window, and the first light-transmitting glass sheet covers the top of the first mounting groove to seal the first mounting groove to prevent the water body to be measured from entering the interior of the first mounting groove; this first light-transmitting glass sheet has good light transmittance and does not affect the ultraviolet light emitted by the excitation light source.

[0013] As a preferred embodiment, a second mounting groove is provided on the circumference of the first mounting groove, the second mounting groove is inclined, the fluorescence monitoring assembly is provided in the second mounting groove, and a second light-transmitting glass sheet is provided on the top of the second mounting groove. The second mounting groove is inclined on the circumference of the first mounting groove, and the center line of the fluorescence monitoring assembly and the center line of the second mounting groove are on the same straight line; the second light-transmitting glass sheet and the first light-transmitting glass sheet are located in the same plane, and the second light-transmitting glass sheet seals the top of the second mounting groove to prevent the water body to be tested from entering the interior of the second mounting groove; the second light-transmitting glass sheet is also a highly light-transmitting glass, and the setting of the second light-transmitting glass sheet does not affect the reception of the fluorescence generated by the ultraviolet light emitted by the excitation light source when the oil in the water body to be tested is irradiated by the filter on the fluorescence monitoring assembly.

[0014] As a preferred embodiment, a cleaning brush is further provided at the first end of the housing, and the cleaning brush is used to clean the first light-transmitting glass sheet and the second light-transmitting glass sheet. The cleaning brush is connected to a motor, and the motor is located inside the housing. The motor is connected to the control circuit board, and a positioning column for limiting the rotation angle of the cleaning brush is provided on the housing. The control circuit board controls the cleaning brush to work or stop through the motor, and controls the rotation time and rotation angle of the cleaning brush to realize automatic cleaning of the cleaning brush. The cleaning brush cleans the first light-transmitting glass sheet and the second light-transmitting glass sheet in time to prevent the water body to be tested from contaminating the first light-transmitting glass sheet and the second light-transmitting glass sheet, and maintains the high light transmittance performance of the first light-transmitting glass sheet and the second light-transmitting glass sheet.

[0015] As a preferred embodiment, a third mounting slot is provided on one side of the first mounting slot, the third mounting slot is arranged at an angle, the light source monitoring detector is installed in the third mounting slot, and the optical channel is used to connect the first mounting slot and the third mounting slot. The third mounting slot is arranged inside the housing, the center line of the third mounting slot is on the same straight line as the center line of the light source monitoring detector, a small hole, i.e., the optical channel, is provided on the side wall of the first mounting slot, so as to realize real-time monitoring of the stability of the excitation light source; using this light source monitoring detector, compensation of the light source intensity is realized, the influence of the intensity fluctuation of the light source itself on the measurement result is reduced, and the monitoring accuracy is improved.

[0016] In another aspect, the present invention provides an online monitoring method for multiple oil content in water based on oil type determination, comprising the following steps:

[0017] S1 Determination of oil type in the water to be tested

[0018] Table 1 Correspondence between crude oil properties and oiliness index in water

[0019] Oil Type Oiliness Index Condensate <1.2 Light oil 1.2-2.8 Medium oil 2.8-4.2 Heavy oil >4.2

[0020] 1) placing the online monitoring device for multiple oil content in water based on oil type determination according to any one of the above items in a water body to be tested, turning on the excitation light source with a central wavelength of 254 nm in the light source assembly to emit ultraviolet light and irradiate the water body to be tested;

[0021] 2) Turn on the two fluorescence monitoring components with the center wavelengths of the filters being 360 nm and 320 nm, receive the fluorescence generated by the oil species in the water to be tested being irradiated by ultraviolet light, and obtain the fluorescence intensity;

[0022] 3) Take the ratio of the two fluorescence intensities to obtain the oiliness index, and use the oiliness index as the basis for determining the oil type. By comparing with Table 1, the oil type in the water to be tested can be obtained;

[0023] S2 Determination of the content of multiple oil species in the water body to be tested

[0024] Table 2 Comparison table of oil types and fluorescence characteristic peak position identification

[0025]

[0026] 4) According to the oil type in the water body to be tested obtained in step 3), refer to Table 2, select the corresponding excitation light source and the fluorescence monitoring component in the light source assembly, turn on the excitation light source and the fluorescence monitoring component in the light source assembly, and the control circuit board obtains the fluorescence intensity of the oil type in the water body. At the same time, turn on the light source monitoring detector and the temperature sensor. Through light source intensity compensation and temperature compensation, the control circuit board compensates and corrects the obtained fluorescence intensity. The control circuit board obtains the content of the oil type in the water body to be tested and transmits it to the host computer, and the content of the oil type in the water body to be tested is read in the host computer.

[0027] The method for online monitoring of the content of multiple oil species in water based on oil species determination of the present invention is a method that can realize real-time online differentiation and determination of multiple oil species. First, the oiliness of unknown oil species is measured and determined. After the oiliness is determined, a suitable band light source and a fluorescence monitoring component are selected for corresponding measurement, so that the oil content of different types of oil species in water can be accurately measured in real time. The light source monitoring detector and the temperature sensor are used to realize the light source intensity and temperature compensation for environmental factors, thereby improving the detection accuracy. Since the excitation light source has a certain instability, it will affect the detection effect of the entire online monitoring device. The intensity of the fluorescence in the water body to be measured is proportional to the light intensity of the excitation light source. The intensity of the excitation light source is monitored through the optical channel, and the excitation light intensity and the monitored fluorescence intensity are normalized, which can effectively eliminate the influence of the change of the excitation light intensity on the measurement result, thereby improving the measurement accuracy and stability. Since the temperature of the water body to be measured will also change the fluorescence excitation efficiency of the oil species in the water body, the temperature of the water body is measured by a temperature sensor, and then the temperature is compensated by setting a control program. The temperature compensation method is as follows: configure a water body with known oil concentration, actively change the temperature of the water body, use an online monitoring device to test the water body under a certain temperature gradient, and record relevant test data, including test concentration, temperature, true concentration, etc.; use common data processing methods such as binary regression and neural network methods to establish an oil concentration prediction model for the online monitoring device, and calculate the model coefficients; use the corrected prediction model to calculate the test data to obtain the temperature compensation result of the online monitoring device.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention has multiple excitation light sources and multiple fluorescence monitoring components, which can determine the oiliness of unknown oil species in the water body to be tested, realize the determination of the content of unknown oil species, and can not only determine the content of light oil, but also determine the content of medium oil and heavy oil, thereby realizing the determination of the content of different types of oil species in water; under the action of the light source monitoring detector, the temperature sensor and the control circuit board, the compensation of the light source intensity and temperature in the process of oil species content determination is realized, the influence of environmental factors such as light source intensity and temperature is eliminated, the detection accuracy is improved, the measurement results are accurate and reliable, and the real-time online monitoring of the content of unknown oil species in the water body is realized, which can be used for monitoring the oil content in the water body during the pollutant discharge process and detecting the type of oil in the rock sample in the oil exploration and development; the structure is simple, the volume is small, the cost is low, the power consumption is low, the application range is wide, and the monitoring accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the three-dimensional structure of an embodiment of an online monitoring device for multiple oil content in water based on oil type determination provided by the present invention;

[0030] Figure 2 for Figure 1 Schematic diagram of the main structure;

[0031] Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure along the AA direction;

[0032] Figure 4 for Figure 3 A schematic diagram of the structure enlarged at C in the middle;

[0033] Figure 5 for Figure 2 Schematic diagram of the cross-sectional structure along the middle BB direction;

[0034] Figure 6 for Figure 1 An enlarged schematic diagram of the structure of the central light source assembly;

[0035] Figure 7 for Figure 1 Schematic diagram of the connection structure of the cleaning brush;

[0036] In the figure: 10-housing; 11-temperature sensor; 12-watertight joint;

[0037] 20-light source assembly; 21-first light-transmitting glass sheet; 22-mounting seat; 23-excitation light source;

[0038] 30-fluorescence monitoring component; 31-photoelectric detector; 32-filter; 33-second light-transmitting glass sheet;

[0039] 40-cleaning brush; 41-positioning column; 42-motor;

[0040] 50-control circuit board;

[0041] 60-light source monitoring detector; 61-optical channel. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Embodiment 1

[0044] See attached Figure 1 , Attachment Figure 2 , Attachment Figure 3 , Attachment Figure 4 , Attachment Figure 5 , Attachment Figure 6 and attached Figure 7The present invention provides an online monitoring device for the content of multiple oil species in water based on oil species determination. This online monitoring device can determine the oiliness of unknown oil species in the water body to be tested, and realizes the determination of the content of unknown oil species. It can not only determine the content of light oil, but also determine the content of medium oil and heavy oil, and realizes the determination of the content of different types of oil species in water. It is a real-time online monitoring device that can determine the oil content of multiple unknown oil species, and has high measurement accuracy.

[0045] See attached Figure 1 , Attachment Figure 2 , Attachment Figure 3 , Attachment Figure 4 , Attachment Figure 5 , Attachment Figure 6 and attached Figure 7The on-line monitoring device for multiple oil content in water based on oil type determination comprises a housing 10, a light source assembly 20, a light source monitoring detector 60, a fluorescence monitoring assembly 30 and a control circuit board 50; the housing 10 is a sealed housing 10, the housing 10 is waterproof, a temperature sensor 11 is provided at the first end of the housing 10, the temperature sensor 11 is used to measure the temperature of the water body to be measured, and a watertight joint 12 is provided at the second end of the housing 10; the light source assembly 20 is arranged at the first end of the housing 10 and is located on the axis of the housing 10, a plurality of excitation light sources 23 are provided on the light source assembly 20, the excitation light source 23 is used to emit ultraviolet light and irradiate the water body to be measured; the light source monitoring detector 60 is arranged at the first end of the housing 10 and is located on the axis of the housing 10, a plurality of excitation light sources 23 are provided on the light source assembly 20, and the excitation light source 23 is used to emit ultraviolet light and irradiate the water body to be measured; the light source monitoring detector 60 is arranged at the housing The first end of the shell 10 is located on one side of the light source assembly 20, the light source monitoring detector 60 is arranged at an angle, and the light source monitoring detector 60 is connected to the light source assembly 20 through an optical channel 61; a plurality of fluorescence monitoring assemblies 30 are also arranged at the first end of the shell 10 and are evenly distributed on the circumference of the light source assembly 20, and the fluorescence monitoring assembly 30 is arranged at an angle to receive the fluorescence generated by the oil in the water body to be tested being irradiated with ultraviolet light; the control circuit board 50 is arranged inside the shell 10, and the light source assembly 20, the light source monitoring detector 60, the fluorescence monitoring assembly 30 and the temperature sensor 11 are all connected to the control circuit board 50, and the control circuit board 50 is connected to the host computer through a watertight joint 12. The present invention has multiple excitation light sources 23 and multiple fluorescence monitoring components 30. The control circuit board 50 is used to control the opening and closing of the light source component 20, the light source monitoring detector 60 and the fluorescence monitoring component 30, the calculation of the oiliness index, the collection and calculation of the fluorescence signal, the light source intensity fluctuation signal and the temperature signal to obtain the concentration of the oil species in the water body and transmit it to the host computer. Under the action of the light source monitoring detector 60, the temperature sensor 11 and the control circuit board 50, the compensation of the light source intensity and temperature in the process of oil species content determination is realized, the influence of environmental factors such as light source intensity and temperature is eliminated, the detection accuracy is improved, the measurement results are accurate and reliable, and the real-time online monitoring of the unknown oil species content in the water body is realized. It has a wide range of applications and can be used for tracking and monitoring of oil spill accidents, monitoring of pollution discharge in marine oil exploration and development, and real-time monitoring of ship desulfurization washing water discharge. It can accurately discover the properties of oil in oil exploration and development; it has a simple structure, small size, low cost, low power consumption and high monitoring accuracy.

[0046] See attached Figure 2 , Attachment Figure 3 , Attachment Figure 4 , Attachment Figure 5 and attached Figure 6As a preferred embodiment, a plurality of excitation light sources 23 are arranged on a mounting base 22, and a plurality of excitation light sources 23 are distributed in a circular array on the mounting base 22 with the axis of the shell 10 as the center line. The plurality of excitation light sources 23 arranged on the mounting base 22 form a light source assembly 20, and the upper computer controls the excitation light source 23 on the light source assembly 20 to turn off or on through the control circuit board 50; the selection of the excitation light source 23 is determined according to the type of oil, and a plurality of excitation light sources 23 can be selected at any time, which is convenient to use. Furthermore, the excitation light source 23 is an LED, and there are three LEDs, and the central wavelengths of the three LEDs are 254nm, 320nm, and 360nm, respectively. The three LEDs can meet the determination of the content of different types of oils, and the LED with the corresponding wavelength is selected according to the oiliness of the oil. See the attached Figure 3 and attached Figure 5 As a preferred embodiment, the fluorescence monitoring component 30 includes a photodetector 31 and a filter 32 disposed at the front end of the photodetector 31. The photodetector 31 controls the reception of the fixed wavelength fluorescence generated by the oil species in the water body to be tested by ultraviolet light irradiation through the filter 32, and then performs photoelectric conversion through the photodetector 31, and converts it into the value of the fluorescence intensity of the oil species in the water body to be tested. According to the linear relationship between the fluorescence intensity in the water body and the oil content in the water body, the value of the oil species concentration in the water body is calculated and displayed in the host computer. Further, there are three fluorescence monitoring components 30, and the central wavelengths of the three filters 32 are 320nm, 360nm, and 460nm, respectively, and the bandwidth is 10nm. The wavelengths that can be passed by the three filters 32 are 310-330nm, 350-370nm, and 450-470nm, respectively. The three filters 32 can be selectively applied to match different types of oil species, thereby accurately realizing the content measurement of unknown oil species.

[0047] See attached Figure 3 , Attachment Figure 4 and attached Figure 5As a preferred embodiment, a first mounting groove is provided at the first end of the shell 10, the light source assembly 20 is arranged in the first mounting groove, and a first light-transmitting glass sheet 21 is provided on the top of the first mounting groove. The center line of the first mounting groove is in the same straight line as the axis of the shell 10. The provision of the first mounting groove facilitates the installation of the light source assembly 20; the first light-transmitting glass sheet 21 is a high-light-transmitting glass, also known as a high-light-transmitting optical window. The first light-transmitting glass sheet 21 covers the top of the first mounting groove and is used to seal the first mounting groove to prevent the water body to be measured from entering the interior of the first mounting groove; this first light-transmitting glass sheet 21 has good light transmittance and does not affect the ultraviolet light emitted by the excitation light source 23. Furthermore, a second mounting groove is provided on the circumference of the first mounting groove, and the second mounting groove is inclined. The fluorescence monitoring assembly 30 is provided in the second mounting groove, and a second light-transmitting glass sheet 33 is provided on the top of the second mounting groove. The second mounting groove is inclined in the circumferential direction of the first mounting groove, and the center line of the fluorescence monitoring assembly 30 is on the same straight line as the center line of the second mounting groove; the second light-transmitting glass sheet 33 and the first light-transmitting glass sheet 21 are located in the same plane, and the second light-transmitting glass sheet 33 seals the top of the second mounting groove to prevent the water body to be tested from entering the interior of the second mounting groove; the second light-transmitting glass sheet 33 is also a high-transmittance glass, and the setting of the second light-transmitting glass sheet 33 does not affect the reception of the fluorescence generated by the ultraviolet light emitted by the excitation light source 23 when the oil in the water body to be tested is irradiated by the filter 32 on the fluorescence monitoring assembly 30.

[0048] See attached Figure 1 , Attachment Figure 2 , Attachment Figure 3 , Attachment Figure 4 and attached Figure 7 As a preferred embodiment, a cleaning brush 40 is further provided at the first end of the housing 10. The cleaning brush 40 is used to clean the first light-transmitting glass sheet 21 and the second light-transmitting glass sheet 33. The cleaning brush 40 is connected to a motor 42. The motor 42 is located inside the housing 10. The motor 42 is connected to the control circuit board 50. The housing 10 is provided with a positioning column 41 for limiting the rotation angle of the cleaning brush 40. There are two positioning columns 41, see the attached Figure 1 and attached Figure 2, the three fluorescence monitoring components 30 are located on the upper half of the circumference of the light source component 20. When the cleaning brush 40 cleans in the counterclockwise direction, it reaches the left side and is restricted by the left positioning column 41 and stops rotating. Then, the cleaning brush 40 continues to clean in the clockwise direction and reaches the right side. It is restricted by the right positioning column 41 and stops rotating. This is repeated to complete the cleaning work. Normally, the control circuit board 50 controls the cleaning brush 40 to work or stop through the motor 42, and controls the rotation time and rotation angle of the cleaning brush 40 to achieve automatic cleaning of the cleaning brush 40. The cleaning brush 40 cleans the first light-transmitting glass sheet 21 and the second light-transmitting glass sheet 33 in time to prevent the water body to be tested from polluting the first light-transmitting glass sheet 21 and the second light-transmitting glass sheet 33, and maintains the high light transmission performance of the first light-transmitting glass sheet 21 and the second light-transmitting glass sheet 33. Further, a third mounting groove is provided on one side of the first mounting groove, and the third mounting groove is inclined. The light source monitoring detector 60 is installed in the third mounting groove, and the optical channel 61 is used to connect the first mounting groove and the third mounting groove. The third mounting groove is arranged inside the shell 10, and the center line of the third mounting groove is on the same straight line as the center line of the light source monitoring detector 60. A small hole, namely the light channel 61, is opened on the side wall of the first mounting groove to realize real-time monitoring of the stability of the excitation light source 23; the light source monitoring detector 60 is used to compensate for the light source intensity, reduce the influence of the light source intensity fluctuation on the measurement result, and improve the monitoring accuracy.

[0049] Embodiment 2

[0050] The present invention also provides an online monitoring method for the content of multiple oil species in water based on oil species determination, comprising the following steps:

[0051] S1 Determination of oil type in the water to be tested

[0052] Table 1 Correspondence between crude oil properties and oiliness index in water

[0053] Oil Type Oiliness Index Condensate <1.2 Light oil 1.2-2.8 Medium oil 2.8-4.2 Heavy oil >4.2

[0054] 1) The online monitoring device for multiple oil content in water based on oil type determination described in Example 1 is placed in a water body to be tested, and the excitation light source 23 with a central wavelength of 254 nm in the light source assembly 20 is turned on to emit ultraviolet light and irradiate the water body to be tested;

[0055] 2) Using quantitative fluorescence analysis technology, two fluorescence monitoring components 30 with central wavelengths of filters 32 of 360nm and 320nm are turned on respectively to receive the fluorescence generated by the oil species in the water body to be tested when irradiated with ultraviolet light. The fluorescence emitted by the irradiated water body to be tested passes through the respective filters 32 and then undergoes photoelectric conversion through the corresponding photodetector 31 to convert it into the value of the fluorescence intensity of the water body to be tested within different wavelength ranges, thereby obtaining the fluorescence intensity;

[0056] 3) Taking the ratio of the above two fluorescence intensities to obtain the oiliness index, the oiliness index is used as the basis for determining the oil type, and the oil type in the water body to be tested is obtained by comparing with Table 1;

[0057] S2 Determination of the content of multiple oil species in the water body to be tested

[0058] Table 2 Comparison table of oil types and fluorescence characteristic peak position identification

[0059]

[0060] 4) According to the oil type in the water body to be tested obtained in step 3), refer to Table 2, select the excitation light source 23 and the fluorescence monitoring component 30 in the corresponding light source assembly 20, turn on the excitation light source 23 and the fluorescence monitoring component 30 in the light source assembly 20, control the circuit board 50 to obtain the fluorescence intensity of the oil type in the water body, and at the same time, turn on the light source monitoring detector 60, and through light source intensity compensation and temperature compensation, control the circuit board 50 to compensate and correct the obtained fluorescence intensity, control the circuit board 50 to obtain the content of the oil type in the water body to be tested and transmit it to the host computer, and read the content of the oil type in the water body to be tested from the host computer.

[0061] The method for online monitoring of the content of multiple oil species in water based on oil species determination of the present invention is a method for realizing real-time online differentiation and determination of multiple oil species. First, the oiliness of unknown oil species is measured and determined. After the oiliness is determined, the excitation light source 23 and the fluorescence monitoring component 30 of the appropriate band are selected for corresponding measurement, so that the oil content of different types of oil species in water can be accurately measured in real time. The light source monitoring detector 60 and the temperature sensor 11 are used to realize the light source intensity and temperature compensation for environmental factors, thereby improving the detection accuracy. Since the excitation light source 23 has a certain instability, it will affect the detection effect of the entire online monitoring device. The intensity of the fluorescence in the water body to be measured is proportional to the light intensity of the excitation light source 23. The intensity of the excitation light source 23 is monitored through the optical channel 61, and the excitation light intensity and the monitored fluorescence intensity are normalized, which can effectively eliminate the influence of the change of the excitation light intensity on the measurement result, thereby improving the measurement accuracy and stability. Since the temperature of the water body to be measured will also change the fluorescence excitation efficiency of the oil species in the water body, the temperature of the water body is measured by the temperature sensor 11, and the temperature is compensated by setting the control program. The temperature compensation method is as follows: configure a water body with known oil concentration, actively change the temperature of the water body, use an online monitoring device to test the water body under a certain temperature gradient, and record relevant test data, including test concentration, temperature, true concentration, etc.; use common data processing methods such as binary regression and neural network methods to establish an oil concentration prediction model for the online monitoring device, and calculate the model coefficients; use the corrected prediction model to calculate the test data to obtain the temperature compensation result of the online monitoring device.

[0062] Embodiment 3

[0063] The present invention provides a method for determining whether an unknown oil type is light oil and determining its content in tracking and monitoring an oil spill accident, comprising the following steps:

[0064] 1) The online monitoring device for multiple oil content in water based on oil type determination described in Example 1 is placed in a water body to be tested where an oil spill accident has occurred, and the excitation light source 23 with a central wavelength of 254 nm in the light source assembly 20 is turned on to emit ultraviolet light and irradiate the water body to be tested;

[0065] 2) Using quantitative fluorescence analysis technology, two fluorescence monitoring components 30 with central wavelengths of filters 32 of 360nm and 320nm are turned on to receive the fluorescence generated by the oil species in the water to be tested. The fluorescence emitted by the irradiated water to be tested passes through the filter 32 and then undergoes photoelectric conversion by the photodetector 31 to convert it into the fluorescence intensity values ​​of the water to be tested within different wavelength ranges, i.e., 324 and 230;

[0066] 3) Taking the ratio of the above two fluorescence intensities, the oiliness index is 1.4. According to Table 1, since 1.4 < 2.8, it can be judged that the oil in the water to be tested is light oil;

[0067] 4) Referring to Table 2, the excitation light source 23 with a central wavelength of 254 nm and the fluorescence monitoring component 30 with a central wavelength of 320 nm in the light source component 20 are turned on, and the control circuit board 50 obtains the fluorescence intensity of the light oil in the water body to be tested. At the same time, the light source monitoring detector 60 and the temperature sensor 11 are turned on, and the fluorescence intensity is compensated and corrected by light source intensity compensation and temperature compensation. According to the linear relationship between the fluorescence intensity of the light oil in the water body to be tested and the content of the light oil, the control circuit board 50 calculates the content of the light oil in the water body to be tested and transmits it to the host computer, and the content of the light oil in the water body to be tested is read from the host computer as 12 ppm.

[0068] Embodiment 4

[0069] The present invention provides a method for determining whether an unknown oil type is medium oil and determining its content in monitoring the discharge of pollutants in offshore oil exploration and development, comprising the following steps:

[0070] 1) The online monitoring device for multiple oil content in water based on oil type determination described in Example 1 is placed in a water body to be tested formed by the discharge of sewage from a certain offshore oil exploration and development, and the excitation light source 23 with a central wavelength of 254 nm in the light source assembly 20 is turned on to emit ultraviolet light and irradiate the water body to be tested;

[0071] 2) Using quantitative fluorescence analysis technology, two fluorescence monitoring components 30 with central wavelengths of 360nm and 320nm of the filter 32 are turned on to receive the fluorescence generated by the oil species in the water to be tested. The fluorescence emitted by the irradiated water to be tested passes through the filter 32 and then undergoes photoelectric conversion through the photodetector 31 to convert it into the numerical value of the fluorescence intensity of the water to be tested within different wavelength ranges, i.e., 424 and 115;

[0072] 3) Taking the ratio of the above two fluorescence intensities, the oiliness index is 3.7. According to Table 1, since 2.8<3.7<4.2, it can be judged that the oil in the water to be tested is medium oil;

[0073] 4) Referring to Table 2, the excitation light source 23 with a central wavelength of 320 nm and the fluorescence monitoring component 30 with a central wavelength of 360 nm in the light source component 20 are turned on, and the control circuit board 50 obtains the fluorescence intensity of the medium oil in the water body to be tested. At the same time, the light source monitoring detector 60 and the temperature sensor 11 are turned on. Through light source intensity compensation and temperature compensation, the control circuit board 50 compensates and corrects the obtained fluorescence intensity. According to the linear relationship between the fluorescence intensity of the medium oil in the water body to be tested and the content of the medium oil, the control circuit board 50 calculates the content of the medium oil in the water body to be tested and transmits it to the host computer. The content of the medium oil in the water body to be tested is read from the host computer as 16 ppm.

[0074] Embodiment 5

[0075] The present invention provides a method for determining whether an unknown oil type is heavy oil and determining its content in real-time monitoring of ship desulfurization washing water discharge, comprising the following steps:

[0076] 1) The online monitoring device for multiple oil content in water based on oil type determination described in Example 1 is placed in a water body to be tested formed by desulfurization discharge washing water of a certain ship, and the excitation light source 23 with a central wavelength of 254 nm in the light source assembly 20 is turned on to emit ultraviolet light and irradiate the water body to be tested;

[0077] 2) Using quantitative fluorescence analysis technology, two fluorescence monitoring components 30 with central wavelengths of 360nm and 320nm of the filter 32 are turned on to receive the fluorescence generated by the oil species in the water to be tested. The fluorescence emitted by the irradiated water to be tested passes through the filter 32 and then undergoes photoelectric conversion by the photodetector 31 to convert it into the fluorescence intensity values ​​of the water to be tested within different wavelength ranges, i.e., 662 and 124;

[0078] 3) Taking the ratio of the above two fluorescence intensities, the oiliness index is 5.3. According to Table 1, since 5.3>4.2, it can be judged that the oil in the water to be tested is heavy oil;

[0079] 4) Referring to Table 2, the excitation light source 23 with a central wavelength of 360 nm and the fluorescence monitoring component 30 with a central wavelength of 460 nm in the light source component 20 are turned on, and the control circuit board 50 obtains the fluorescence intensity of the heavy oil in the water body to be tested. At the same time, the light source monitoring detector 60 and the temperature sensor 11 are turned on. Through light source intensity compensation and temperature compensation, the control circuit board 50 compensates and corrects the obtained fluorescence intensity. According to the linear relationship between the fluorescence intensity of the heavy oil in the water body to be tested and the content of the heavy oil, the control circuit board 50 calculates the content of the heavy oil in the water body to be tested and transmits it to the host computer. The content of the heavy oil in the water body to be tested is read from the host computer as 24 ppm.

[0080] Therefore, compared with the prior art, the beneficial effects of the present invention are as follows: the present invention has multiple excitation light sources 23 and multiple fluorescence monitoring components 30, which can determine the oiliness of unknown oil species in the water body to be tested, and realize the determination of the content of unknown oil species. Not only can the content of light oil be determined, but also the content of medium oil and heavy oil can be determined, and the content of different types of oil species in water can be determined; under the action of the light source monitoring detector 60, the temperature sensor 11 and the control circuit board 50, the compensation of the light source intensity and temperature in the process of oil species content determination is realized, the influence of environmental factors such as light source intensity and temperature is eliminated, the detection accuracy is improved, the measurement results are accurate and reliable, and the real-time online monitoring of the content of unknown oil species in the water body is realized, which can be used for monitoring the oil content in the water body during the pollutant discharge process and detecting the type of oil in the rock sample in the oil exploration and development; the structure is simple, the volume is small, the cost is low, the power consumption is low, the application range is wide, and the monitoring accuracy is high.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An online monitoring method for the content of multiple oil species in water based on oil species determination, characterized in that: The method for online monitoring of the content of multiple oil species in water based on oil species determination is completed by using an online monitoring device for the content of multiple oil species in water based on oil species determination. The online monitoring device for the content of multiple oil species in water based on oil species determination comprises: A shell, wherein the shell is a sealed shell, a temperature sensor is provided at a first end of the shell, the temperature sensor is used to measure the temperature of a water body to be measured, and a watertight joint is provided at a second end of the shell; A light source assembly, the light source assembly is arranged at the first end of the shell and is located on the axis of the shell, the light source assembly is provided with three excitation light sources, the excitation light sources are used to emit ultraviolet light and irradiate into the water body to be tested, the excitation light sources are LEDs, and the central wavelengths of the three LEDs are 254nm, 320nm, and 360nm respectively; A light source monitoring detector, which is arranged at the first end of the housing and located on one side of the light source assembly, the light source monitoring detector is arranged obliquely, and the light source monitoring detector is connected to the light source assembly through an optical channel; A fluorescence monitoring assembly, wherein three fluorescence monitoring assemblies are also arranged at the first end of the shell and are evenly distributed around the light source assembly. The fluorescence monitoring assembly is arranged obliquely to receive the fluorescence generated by the oil in the water body to be tested when irradiated with ultraviolet light. The fluorescence monitoring assembly includes a photodetector and a filter arranged at the front end of the photodetector. The central wavelengths of the three filters are 320nm, 360nm, and 460nm, respectively, and the bandwidth is 10nm. A control circuit board, wherein the control circuit board is arranged inside the housing, the light source assembly, the light source monitoring detector, the fluorescence monitoring assembly and the temperature sensor are all connected to the control circuit board, and the control circuit board is connected to a host computer through the watertight joint; The method for online monitoring of multiple oil content in water based on oil type determination comprises the following steps: S1 Determination of oil type in the water to be tested 1) placing the online monitoring device for multiple oil content in water based on oil type determination in a water body to be tested, turning on an excitation light source with a central wavelength of 254 nm in the light source assembly to emit ultraviolet light and irradiate the water body to be tested; 2) Turn on the two fluorescence monitoring components with the center wavelengths of the filters being 360nm and 320nm, receive the fluorescence generated by the oil species in the water body to be tested when irradiated with ultraviolet light, and obtain the fluorescence intensity; 3) Take the ratio of the two fluorescence intensities to get the oiliness index, and use the oiliness index as the basis for oil type determination. According to the corresponding relationship between the properties of crude oil in the water body and the oiliness index, when the oiliness index is less than 1.2, the oil type is condensate oil; when the oiliness index is not less than 1.2 and not greater than 2.8, the oil type is light oil; when the oiliness index is greater than 2.8 and not greater than 4.2, the oil type is medium oil; when the oiliness index is greater than 4.2, the oil type is heavy oil. The oil type in the water body to be tested is obtained; S2 Determination of the content of multiple oil species in the water body to be tested 4) According to the oil species in the water body to be tested obtained in step 3), the oil species and the characteristic wavelength required for fluorescence characteristic peak position identification are compared. When the oil species is condensate oil and light oil, the excitation wavelength Ex of its fluorescence characteristic peak is 254 nm and the receiving wavelength Em is 320 nm. When the oil species is medium oil, the excitation wavelength Ex of its fluorescence characteristic peak is 320 nm and the receiving wavelength Em is 360 nm. When the oil species is heavy oil, the excitation wavelength Ex of its fluorescence characteristic peak is 360 nm and the receiving wavelength Em is 460 nm. Select the corresponding excitation light source and the fluorescence monitoring component in the light source assembly, turn on the excitation light source and the fluorescence monitoring component in the light source assembly, and the control circuit board obtains the fluorescence intensity of the oil species in the water body. At the same time, turn on the light source monitoring detector and the temperature sensor. Through light source intensity compensation and temperature compensation, the control circuit board compensates and corrects the obtained fluorescence intensity. The control circuit board obtains the content of the oil species in the water body to be tested and transmits it to the host computer, and the content of the oil species in the water body to be tested is read in the host computer.

2. The method for online monitoring of multiple oil content in water based on oil type determination according to claim 1 is characterized in that: The three excitation light sources are all arranged on a mounting base, and the three excitation light sources are distributed in a circular array on the mounting base with the axis of the shell as the center line.

3. The method for online monitoring of multiple oil content in water based on oil type determination according to claim 1 is characterized in that: A first mounting groove is provided at the first end of the housing, the light source assembly is arranged in the first mounting groove, and a first light-transmitting glass sheet is provided at the top of the first mounting groove.

4. The method for online monitoring of multiple oil content in water based on oil type determination according to claim 3 is characterized in that: A second mounting groove is provided on the circumference of the first mounting groove, the second mounting groove is inclined, the fluorescence monitoring component is arranged in the second mounting groove, and a second light-transmitting glass sheet is provided on the top of the second mounting groove.

5. The method for online monitoring of multiple oil content in water based on oil type determination according to claim 4 is characterized in that: A cleaning brush is also provided at the first end of the shell, and the cleaning brush is used to clean the first light-transmitting glass sheet and the second light-transmitting glass sheet. The cleaning brush is connected to a motor, and the motor is located inside the shell. The motor is connected to the control circuit board, and a positioning column is provided on the shell for limiting the rotation angle of the cleaning brush.

6. The method for online monitoring of multiple oil content in water based on oil type determination according to claim 3 is characterized in that: A third mounting groove is provided on one side of the first mounting groove, the third mounting groove is inclined, the light source monitoring detector is installed in the third mounting groove, and the optical channel is used to connect the first mounting groove and the third mounting groove.

Images