CN105675501A - Fluid component analyzer and detection channel arrangement method thereof - Google Patents

Abstract

The present invention relates to a fluid component analyzer and a method for arranging detection channels thereof, which includes a host computer, a control system, a light source module, an optical probe and several detectors, wherein the optical probe includes several detection channels, and The channels correspond to the detectors one by one; the host computer is for the user to input control commands and send the control commands to the control system, the control system receives the control commands and drives the light source module to emit light, and the light source module sends the emitted light through the optical probe to the On the surface of the fluid, the light is reflected on the surface of the fluid to be tested and sent to the detector through each detection channel. The value is compared with the standard library to determine the composition and ratio of the fluid to be tested. The invention can quickly and real-time determine the proportion of each component in the fluid.

Description

A fluid component analyzer and its detection channel arrangement method

technical field

The invention relates to the field of exploration and collection of oil and gas resources, in particular to a fluid component analyzer and a detection channel arrangement method thereof.

Background technique

In the process of oil and gas exploration and development, bottom testing instruments need to measure various parameters of downhole fluid, such as fluid velocity, fluid composition, etc., and optimize the fluid sampling process according to the measured parameters. The oil-gas ratio parameter in , and the oil-gas ratio parameter is defined as the relative proportion of oil, water and gas in the fluid over a period of time. At present, oil-gas ratio parameters are generally measured by sampling. This measurement method not only cannot achieve fast and real-time measurement, but also has a long measurement cycle and cumbersome measurement operations.

Contents of the invention

In view of the above problems, the object of the present invention is to provide a fluid component analyzer and a method for arranging detection channels thereof, which can quickly and real-time determine the proportion of each component in the fluid.

In order to achieve the above-mentioned technical purpose, the present invention adopts the following technical solutions: a fluid component analyzer, which includes a host computer, a control system, a light source module, an optical probe and several detectors, wherein the optical probe includes Several detection channels, and the detection channels correspond to the detectors one by one; the host computer allows the user to input control commands, and sends the control commands to the control system, and the control system receives the control commands and drives the light source module emit light, the light source module sends the emitted light to the surface of the fluid to be tested through the optical probe, the light is reflected on the surface of the fluid to be tested and sent to the detector through each detection channel, and the detector will detect The reflected light intensity signal is sent to the host computer through the control system, and the host computer compares the light intensity values detected by each detector with the standard library, and then determines the composition and proportion of the fluid to be tested.

A modulation module, a digital lock-in amplifier and a light intensity normalization module are set in the control system; the modulation module generates a modulation signal after receiving the control command from the host computer, and sends the modulation signal to a light source driver circuit, the light source driving circuit receives a modulation signal to drive the light source module to emit light, the light intensity signal sent by the light source module is monitored by a light intensity detector, and the light intensity detector sends the detected light intensity signal To the digital lock-in amplifier, the digital lock-in amplifier receives the light intensity signal, and receives the reflected light intensity signal detected by each detector at the same time, and the digital lock-in amplifier adopts the same modulation signal as that of the modulation module The signal of the light intensity detector is used as a reference signal, and the light intensity signal detected by the light intensity detector and the reflected light intensity signal detected by each detector are phase-sensitively demodulated and then sent to the light intensity normalization module. The light intensity normalization module normalizes the reflected light intensity signals detected by each of the detectors and sends them to the host computer.

The light source module includes a light source, a fiber coupler and a multimode fiber; the light source sends the emitted light to the optical probe through the fiber coupler and the multimode fiber in sequence.

The optical probe includes a sapphire prism, a gland, a polarizer and an optical fiber end, wherein the two ends of the top of the sapphire prism are symmetrically cut into an incident plane and a detection plane; the center of the top of the sapphire prism is spaced apart Two installation holes, the shape of the gland corresponds to the shape of the top of the sapphire prism; the bottom end of the gland corresponding to the detection surface is laterally spaced with each detection channel, corresponding to the position of the installation hole , the center of the bottom of the gland is provided with a blind hole, and the blind hole and the installation hole are fixedly connected by a screw; the other end of the bottom of the gland corresponding to the incident surface is provided with a through hole, and the incident surface is pasted with a fixed place The polarizer, one end of the optical fiber end is perpendicular to the polarizer, and the other end of the optical fiber end is connected to the multimode optical fiber through the through hole.

Each of the detectors detects the reflected light intensity signal through the receiving optical fiber, and converts the detected reflected light intensity signal into a current signal and sends it to a detector amplifying circuit, and the detector amplifying circuit converts each current signal into a voltage signal, and amplify the amplitude of each voltage signal and send it to the control system.

The upper computer is located in the well, the control system, light source module, optical probe and detector are located in the downhole, and the control system, light source module and detector are arranged in a thermal insulation structure.

The standard manufacturing method comprises the following steps: 1) by measuring the light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is pure air, the light intensity monitored by the light intensity detector is Intensity is the standard light intensity, and the light intensity detected by each detection channel is normalized to obtain the standard library of pure air; The light intensity monitored is normalized to the light intensity detected by each detection channel with the light intensity monitored by the light intensity detector as the standard light intensity to obtain the standard library of pure oil; 3) the fluids obtained by measurement are in different proportions The light intensity detected by each detection channel and the light intensity detected by the light intensity detector are used to normalize the light intensity detected by each detection channel with the light intensity detected by the light intensity detector as the standard light intensity 4) by measuring the light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is pure water, the light intensity monitored by the light intensity detector is The light intensity is the standard light intensity, and the light intensity detected by each detection channel is normalized to obtain the standard library of pure water; 5) the light intensity detected by each detection channel is obtained by measurement when the fluid is oil and water in different proportions and the light intensity monitored by the light intensity detector, the light intensity detected by each detection channel is normalized with the light intensity monitored by the light intensity detector as the standard light intensity, and the standard library of oil and water in different proportions is obtained; 6) When the fluids are different proportions of oil and gas and different proportions of oil and water, the normalized light intensity detected by each detection channel is compared with that of pure oil when the fluid is pure oil. The increment of the light intensity, and store all the increments of the light intensity in the standard library.

A method for arranging the detection channels of a fluid component analyzer comprises the following steps: 1) respectively determining the refractive indices of air, water, oil and sapphire prisms, and drawing the interfaces to be measured as prism/air, prism/water and prism/prism respectively 2) According to the curves of reflectivity changing with incident angle when the interface to be measured is prism/air, prism/water and prism/oil, respectively, it is determined that the interface to be measured is prism/ The critical angles for total reflection for air, prism/water, and prism/oil are compared between the critical angles for total reflection from prism/air to prism/water and the critical angles for total reflection from prism/water to prism/oil Correspondingly set the detection channel of the optical probe.

Because the present invention adopts the above technical scheme, it has the following advantages: 1. When the present invention is based on the fact that the fluid is composed of different proportions of different components, the reflected light intensity signals detected by each detection channel are different, and the detected reflected light intensity signals Compared with the standard library, the components and their ratios in the fluid can be determined, avoiding the cumbersome operation of sampling and measurement. 2. The present invention sends the modulation signal by setting the modulation module, and performs phase-sensitive demodulation through the digital lock-in amplifier, so it can not only reduce the interference of noise to the detection signal, but also avoid the complex system structure caused by the lock-in amplifier composed of independent devices and decreased stability. 3. Because the optical probe of the present invention adopts sapphire prism, it can be applied to the downhole high temperature and high pressure environment; because the present invention specifically sets the shape of the optical probe, it is easy to seal and further adapts to the downhole high temperature and high pressure environment. 4. Since the present invention arranges the control system, the light source module and the detector in the heat preservation structure, it can be applied to the underground high temperature and high pressure environment and improve the working life of the equipment. 5. The present invention determines the arrangement of each detection channel according to the graph of the change of reflectivity with the incident angle when the interface to be tested is different substances, so that the component identification of multi-component fluid can be realized. 6. The present invention effectively improves the energy utilization efficiency of the light source due to the arrangement of the fiber coupler. 7. The present invention can effectively control the polarization state of the light emitted from the end of the optical fiber due to the arrangement of the polarizer. 8. Since the present invention is equipped with a light intensity detector and a light intensity normalization module, it can effectively eliminate the measurement error caused by the shaking of the light source and ensure the accuracy of the measurement result. The invention has simple design structure, convenient operation, and high real-time performance and high accuracy of the measurement results, so it can be widely used in technical fields such as oil field downhole fluid oil-gas ratio measurement, drilling fluid pollution detection, and on-site component measurement of fluids in the downhole. Provide basis for oilfield production decision-making.

Description of drawings

Fig. 1 is the functional block diagram of fluid component analyzer of the present invention;

Fig. 2 is the structural representation of fluid component analyzer of the present invention;

Fig. 3 is the schematic diagram of the three-dimensional structure of the sapphire prism of the present invention;

Fig. 4 is the front view structure schematic diagram of sapphire prism of the present invention;

Fig. 5 is the left view structural representation of sapphire prism of the present invention;

Fig. 6 is the top view structural representation of sapphire prism of the present invention;

Fig. 7 is a three-dimensional structural schematic view of the gland of the present invention;

Fig. 8 is a schematic diagram of the bottom view of Fig. 7;

Fig. 9 is a front structural schematic view of the gland of the present invention;

Fig. 10 is a right view structural diagram of the gland of the present invention;

Fig. 11 is a schematic diagram of the cross-sectional structure of A-A in Fig. 10;

Fig. 12 is a schematic cross-sectional structure diagram of Fig. 10;

Fig. 13 is a graph showing the variation of reflectivity with incident angle when the interfaces to be measured are prism/air, prism/water and prism/oil, wherein the abscissa represents the incident angle in degrees, and the ordinate represents the reflectivity.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figures 1-2, the fluid component analyzer of the present invention includes a host computer 1, a control system 2, a light source module 3, an optical probe 4 and several detectors 5, wherein the optical probe 4 includes several detectors Channel 41, the specific number of detection channels 41 is determined according to the accuracy and speed required for the measurement, and is not limited here, and the detection channels 41 correspond to the detectors 5 one by one. In this embodiment, seven detection channels 41 are set, corresponding to The detector 5 sets seven;

The upper computer 1 is for the user to input control commands, and sends the control commands to the control system 2, the control system 2 receives the control commands and drives the light source module 3 to emit light, and the light source module 3 sends the emitted light through the optical probe 4 to the On the surface of the fluid 6, the light is reflected on the surface of the fluid 6 to be tested and sent to the detector 5 through each detection channel 41, and the detector 5 sends the detected reflected light intensity signal to the host computer 1 through the control system 4, and the host computer 1 will The light intensity value detected by each detector 5 is compared with the standard library to determine the composition and ratio of the fluid to be tested.

In a preferred embodiment, the upper computer 1 performs two-way communication with the control system 2 through the serial communication device 7, and uses RS485 or RS232 communication protocol.

In a preferred embodiment, the control system 2 can be composed of FPGA or DSP; a modulation module, a digital lock-in amplifier and a light intensity normalization module are arranged in the control system 2; the modulation module receives the control instruction of the host computer 1 Finally, the modulation signal is generated, and the modulation signal is sent to a light source driving circuit 21, the light source driving circuit 21 receives the modulation signal to drive the light source module 3 to emit light, and the light intensity signal sent by the light source module 3 is monitored by a light intensity detector 22, and the light intensity Detector 22 sends the light intensity signal that it monitors to digital lock-in amplifier, and digital lock-in amplifier receives light intensity signal, receives the reflected light intensity signal that each detector 5 detects simultaneously, and digital lock-in amplifier adopts the same As a reference signal, the light intensity signal monitored by the light intensity detector 22 and the reflected light intensity signal detected by each detector 5 are phase-sensitively demodulated and sent to the light intensity normalization module, and the light intensity normalization The module uses the light intensity signal detected by the light intensity detector 22 as the standard light intensity to normalize the reflected light intensity signal detected by each detector 5 and then sends it to the host computer 1 .

In a preferred embodiment, the light source module 3 includes a light source 31, a fiber coupler 32 and a multimode optical fiber 8; After coupling, it is sent to the optical probe 4 through the multimode optical fiber 8, wherein the light source 31 can be a laser or LED, and the wavelength of the light source 31 can be near-infrared light band or visible light band.

In a preferred embodiment, as shown in Figures 3-12, the optical probe 4 includes a sapphire prism 42, a gland 43, a polarizer 44 and a SMA905 fiber end 45, wherein the sapphire prism 42 is a cylinder Body structure, the two ends of the top of the sapphire prism 42 are symmetrically cut into an incident surface 421 and a detection surface 422; the top center of the top of the sapphire prism 42 is provided with two mounting holes 423 at intervals, and the shape of the gland 43 corresponds to the shape of the top of the sapphire prism 43 , so as to ensure that the gland 43 can be fastened with the top of the sapphire prism 42; the bottom end of the gland 43 corresponding to the detection surface 422 is provided with detection channels 41 at intervals transversely, corresponding to the positions of the mounting holes 423, and the center of the bottom of the gland 43 is set Blind hole 431, the blind hole 431 and the mounting hole 423 are fixedly connected by a screw, so that the gland 43 and the sapphire prism 42 are fixedly connected as one, and the other end of the bottom of the gland 43 corresponding to the incident surface 421 is provided with a through hole, through which A mounting seat 432 is fixed outside the hole, and a fixed polarizer 44 is pasted on the incident surface 421. One end of the SMA905 fiber end 45 is perpendicular to the polarizing plate 44, and the other end of the SMA905 fiber end 45 passes through the through hole and is connected to the mounting seat 432 in turn. Multimode fiber 8.

In a preferred embodiment, each detector 5 detects the reflected light intensity signal through the receiving optical fiber 51, and converts the detected reflected light intensity signal into a current signal and sends it to a detector amplifier circuit 52. The detector amplifier circuit 52 converts each current signal into a voltage signal, amplifies the amplitude of each voltage signal and sends it to the control system 2 .

In a preferred embodiment, the upper computer 1 is located on the well, the control system 2, the light source module 3, the optical probe 4 and the detector 5 are located in the downhole, and the control system 2, the light source module 3 and the detector 4 are arranged in a thermal insulation structure 9 Inside.

The method for arranging the detection channels of the fluid composition analyzer of the present invention comprises the following steps:

1. Determine the refractive indices of air, water, oil and sapphire prisms respectively, and draw the curves of reflectance versus incident angle when the interfaces to be tested are prism/air, prism/water and prism/oil respectively, as shown in Figure 13;

2. According to the plotted curves of the change of reflectivity with the incident angle when the interface to be tested is prism/air, prism/water and prism/oil, respectively, it is determined that the interface to be tested is prism/air, prism/water and prism/oil. The critical angle of total reflection, the detection channel is set on the optical probe corresponding to the critical angle of total reflection from prism/air to prism/water and the critical angle of total reflection from prism/water to prism/oil. Description, the detection channel of the optical probe corresponding to the critical angle of total reflection from prism/air to prism/water is called the first group of detection channels, and between the critical angle of total reflection from prism/water to prism/oil The detection channels provided on the corresponding optical probes are called the second group of detection channels.

The method for making the standard library of the fluid component analyzer of the present invention comprises the following steps:

1. By measuring the light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is pure air, the light intensity detected by the light intensity detector is used as the standard light intensity for each detection channel. Normalize the light intensity to obtain the standard library of pure air, where the calculation formula for normalizing the light intensity detected by each detection channel is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}$

In the formula, Indicates the normalized light intensity value when the fluid is pure air; Represents the light intensity detected by the i-th detection channel, in this embodiment, i=1,2...7; v ₀ represents the light intensity detected by the light intensity detector;

2. When the fluid is pure oil, the light intensity detected by each detection channel and the light intensity detected by the light intensity detector are obtained through measurement, and the light intensity detected by the light intensity detector is used as the standard light intensity to detect the detected light intensity of each detection channel. Normalize the light intensity to obtain the standard library of pure oil, where the calculation formula for normalizing the light intensity detected by each detection channel is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula, Indicates the normalized light intensity value when the fluid is pure oil; Indicates the light intensity detected by the i-th detection channel; v ₁ indicates the light intensity detected by the light intensity detector;

3. The light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is oil and gas in different proportions (the proportion interval value between different proportions is generally 5%) is obtained by measuring the light intensity The light intensity detected by the detector is the standard light intensity. The light intensity detected by each detection channel is normalized to obtain the standard library of oil and gas with different proportions. Among them, the light intensity detected by each detection channel is normalized The calculated formula is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula, Indicates the normalized light intensity value when the fluid is oil and gas in different proportions; Indicates the light intensity detected by the i-th detection channel; v _std1 indicates the light intensity detected by the light intensity detector;

4. When the fluid is pure water, the light intensity detected by each detection channel and the light intensity detected by the light intensity detector are obtained through measurement, and the light intensity detected by the light intensity detector is used as the standard light intensity to detect the light intensity detected by each detection channel. Normalize the light intensity to obtain the standard library of pure water. The calculation formula for normalizing the light intensity detected by each detection channel is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}$

In the formula, Indicates the normalized light intensity value when the fluid is pure water; Indicates the light intensity detected by the i-th detection channel; v ₂ indicates the light intensity detected by the light intensity detector;

5. When the fluid is oil and water in different proportions, the light intensity detected by each detection channel and the light intensity detected by the light intensity detector are obtained through measurement. The light intensity monitored by the light intensity detector is used as the standard light intensity for each The light intensity detected by the detection channel is normalized to obtain the standard library of different proportions of oil and water. The calculation formula for normalizing the light intensity detected by each detection channel is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

In the formula, Indicates the normalized light intensity value when the fluid is oil and water in different proportions; Indicates the light intensity detected by the i-th detection channel; v _std2 indicates the light intensity detected by the light intensity detector;

6. When the fluid is different proportions of oil and gas and different proportions of oil and water through calculation, the normalized light intensity detected through each detection channel is compared to when the fluid is pure oil. The increment of the light intensity, and store all the increments of the light intensity in the standard library, where the calculation formula of the light intensity increment is as follows:

${\mathrm{<span\; class="notranslate">\; Std</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>$

In the formula, Indicates the light intensity increment stored in the standard library when the fluid is oil and gas with different proportions;

When the fluid is oil and water in different proportions, the formula for calculating the light intensity increment is as follows:

${\mathrm{<span\; class="notranslate">\; Std</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>$

In the formula, Indicates the light intensity increment stored in the standard library when the fluid is oil and water in different proportions.

The use of fluid component analyzer of the present invention comprises the following contents:

1. Insert the optical probe 4 into a detection hole 61 provided on a downhole fluid pipeline, and make the bottom surface of the optical probe 4 contact the surface of the fluid 6 to be measured;

2. The host computer 1 sends the control command to the control system 2, the control system 2 receives the control command and drives the light source module 3 to emit light, and the light source module 3 sends the light through the multimode fiber 8 and the SMA905 fiber port 45 to the polarizer 44 in sequence , the polarizing plate 44 converts the outgoing light of the SMA905 fiber port 45 into polarized light in a divergent state, so that the incident light has different incident angles and then enters the sapphire prism 42, and illuminates one of the interfaces between the sapphire prism 42 and the surface of the fluid to be measured 6 An elliptical area where reflections occur;

3. Each detector 5 detects the reflected light intensity signal through the corresponding detection channel 41 and sends it to the host computer 1 through the control system 2 after processing, and the host computer 1 processes each reflected light intensity signal and obtains a period of time (a period of time) respectively The time is usually 30S～60S) when the light intensity detected by each detector 5 is pure oil relative to the fluid, the incremental average value of the light intensity detected by each detection channel will be compared with the light intensity detected by the first group of detection channels When the light intensity is pure oil relative to the fluid, the average value of the light intensity increments detected by each detection channel and the light intensity detected by the second group of detection channels are detected by each detection channel when the light intensity is pure oil relative to the fluid. If there is no significant difference in the comparison results (obvious difference means that the error of the comparison results is greater than the ratio interval value of oil and gas or oil and water in the standard library), it means that the fluid is composed of oil and air. It only needs to calculate the proportion of air in the fluid, and the proportion of oil in the fluid can be calculated through the proportion of air. The calculation process of the proportion of air in the fluid includes the following steps:

1) Normalize the reflected light intensity signals detected by the first group of detection channels and the second group of detection channels respectively, and the calculation formula is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}$

In the formula, Indicates the normalized light intensity value; Indicates the reflected light intensity signal detected by the i (i=1,2...7) detection channel; v _mea1 indicates the light intensity detected by the light intensity detector;

2) Calculate the normalized reflected light intensity signal detected by each detection channel relative to the fluid as pure oil, the increment of light intensity detected by each detection channel, the calculation formula is as follows:

${\mathrm{<span\; class="notranslate">\; Std</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>$

In the formula, Indicates the increment of light intensity;

3) Calculate the increment of light intensity over a period of time and store the average value and the light intensity increment in the standard library when the fluid is different proportions of oil and gas For comparison, use the look-up table method and linear interpolation method to determine the proportion of air in the fluid;

4) Subtract the proportion of air in the fluid by 100% to obtain the proportion of oil in the fluid;

If there is a significant difference in the comparison results, it means that the fluid is composed of air, water and oil. At this time, it is only necessary to calculate the proportion of air and water in the fluid, and the proportion of oil in the fluid can be calculated from the proportion of air and water. Among them, The calculation process of the proportion of air in the fluid is basically the same as the above steps, the only difference is that only the reflected light intensity signal detected by the first group of detection channels is used to calculate the corresponding normalized light intensity value, so it will not be used here repeat;

The calculation process of the proportion of water in the fluid includes the following steps:

1) Normalize the reflected light intensity signals detected by the second group of detection channels, and the calculation formula is as follows:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

In the formula, Indicates the normalized light intensity value; Indicates the light intensity detected by the i (i=6,7) detection channel; _vmea2 indicates the light intensity detected by the light intensity detector;

2) Calculate the normalized reflection light intensity signal detected by the second group of detection channels relative to the fluid as pure oil, the increment of light intensity detected by each detection channel, the calculation formula is as follows:

${\mathrm{<span\; class="notranslate">\; Std</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; e</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>$

In the formula, Indicates the light intensity increment;

3) Calculate the light intensity increment over a period of time The average value, and when the average value and the fluid are different proportions of oil and water, the light intensity increment stored in the standard library For comparison, use the look-up table method and linear interpolation method to determine the proportion of water in the fluid;

4) Subtract the proportion of air and water in the fluid from 100% to obtain the proportion of oil in the fluid.

The foregoing embodiments are only used to illustrate the present invention, wherein the structure, connection mode and manufacturing process of each component can be changed to some extent, and any equivalent transformation and improvement carried out on the basis of the technical solution of the present invention should not be excluded. Outside the protection scope of the present invention.

Claims (8)

1. A fluid component analyzer, characterized in that: it includes a host computer, a control system, a light source module, an optical probe and some detectors, wherein the optical probe comprises several detection channels, and the One-to-one correspondence between detection channels and detectors; The upper computer is for the user to input control commands, and sends the control commands to the control system, and the control system receives the control commands and drives the light source module to emit light, and the light source module passes the emitted light through the optical probe Send to the surface of the fluid to be tested, the light is reflected on the surface of the fluid to be tested and sent to the detector through each detection channel, and the detector sends the detected reflected light intensity signal to the host computer through the control system , the host computer compares the light intensity values detected by each of the detectors with the standard library, and then determines the components and proportions of the fluid to be tested. 2. a kind of fluid component analyzer as claimed in claim 1, is characterized in that: a modulation module, a digital lock-in amplifier and a light intensity normalization module are set in the described control system; The modulation signal is generated after the control command of the host computer, and the modulation signal is sent to a light source driving circuit, the light source driving circuit receives the modulation signal to drive the light source module to emit light, and the light intensity signal sent by the light source module passes through a light source Intensity detector monitoring, the light intensity detector sends the light intensity signal it monitors to the digital lock-in amplifier, and the digital lock-in amplifier receives the light intensity signal and receives the reflections detected by each detector For the light intensity signal, the digital lock-in amplifier uses the same signal as the modulation signal of the modulation module as a reference signal, and the light intensity signal monitored by the light intensity detector and the reflected light detected by each detector The strong signal is sent to the light intensity normalization module after phase-sensitive demodulation, and the light intensity normalization module normalizes the reflected light intensity signal detected by each detector and then sends it to the upper machine. 3. A kind of fluid composition analyzer as claimed in claim 2, is characterized in that: described light source module comprises a light source, a fiber optic coupler and a multimode optical fiber; Described light source passes the light that sends out through described A fiber coupler and multimode fiber are sent to the optical probe. 4. A kind of fluid composition analyzer as claimed in claim 2, it is characterized in that: said optical probe comprises a sapphire prism, a gland, a polarizer and an optical fiber end, wherein, said sapphire prism top two An incident surface and a detection surface are cut symmetrically at the end; two installation holes are arranged at intervals in the center of the top of the sapphire prism, and the shape of the gland is corresponding to the shape of the top of the sapphire prism; the pressure cover corresponding to the detection surface One end of the bottom of the cover is provided with each of the detection channels at intervals laterally, corresponding to the position of the installation hole, and a blind hole is arranged in the center of the bottom of the gland, and the blind hole and the installation hole are fixedly connected by a screw; the corresponding to the incident surface The other end of the bottom of the gland is provided with a through hole, the polarizer is pasted and fixed on the incident surface, one end of the optical fiber end is perpendicular to the polarizer, and the other end of the optical fiber end passes through the through hole Connect the multimode fiber. 5. A kind of fluid component analyzer as claimed in claim 1 or 2 or 3 or 4, characterized in that: each of the detectors detects the reflected light intensity signal through the receiving optical fiber, and the detected reflected light intensity signal Converted into current signals and then sent to a detector amplifier circuit, the detector amplifier circuit converts each current signal into a voltage signal, amplifies the amplitude of each voltage signal and sends it to the control system. 6. A kind of fluid component analyzer as claimed in claim 1 or 2 or 3 or 4, characterized in that: the host computer is located on the well, and the control system, light source module, optical probe and detector are located down the well, and The control system, light source module and detector are arranged in a heat preservation structure. 7. A kind of fluid composition analyzer described in claim 1 or 2 or 3 or 4, is characterized in that: the manufacturing method of described standard, it comprises the following steps: 1) By measuring the light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is pure air, the light intensity detected by the light intensity detector is used as the standard light intensity to detect the light intensity of each detection channel The light intensity is normalized to obtain the standard library of pure air; 2) When the fluid is pure oil, the light intensity detected by each detection channel and the light intensity detected by the light intensity detector are obtained through measurement, and the light intensity detected by the light intensity detector is used as the standard light intensity for each detection channel. Normalize the light intensity to obtain the standard library of pure oil; 3) The light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is different proportions of oil and gas are obtained by measurement, and the light intensity detected by the light intensity detector is used as the standard light intensity for each detection channel. The light intensity detected by the channel is normalized to obtain the standard library of different proportions of oil and gas; 4) When the fluid is pure water, the light intensity detected by each detection channel and the light intensity detected by the light intensity detector are obtained through measurement, and the light intensity detected by the light intensity detector is used as the standard light intensity for each detection channel. Normalize the light intensity to obtain the standard library of pure water; 5) By measuring the light intensity detected by each detection channel and the light intensity detected by the light intensity detector when the fluid is oil and water in different proportions, the light intensity detected by the light intensity detector is used as the standard light intensity for each The light intensity detected by the detection channel is normalized to obtain the standard library of oil and water in different proportions; 6) When the fluids are different proportions of oil and gas and different proportions of oil and water, the normalized light intensity detected by each detection channel is compared with that of pure oil when the fluid is pure oil. The increment of the light intensity, and store all the increments of the light intensity in the standard library. 8. A method for arranging the detection channels of the fluid component analyzer according to any one of claims 1 to 7, characterized in that it comprises the following steps: 1) Determine the refractive indices of air, water, oil, and sapphire prisms respectively, and draw the curves of reflectance versus incident angle when the interfaces to be measured are prism/air, prism/water, and prism/oil respectively; 2) According to the plotted curves of the change of reflectivity with the incident angle when the interface to be tested is prism/air, prism/water and prism/oil, it is determined that the interface to be tested is prism/air, prism/water and prism/oil. The critical angle of total reflection, and the critical angle of total reflection from prism/air to prism/water, and the critical angle of total reflection from prism/water to prism/oil are set corresponding to the detection channel of the optical probe.