Control method, control module and instrument for oil water content analysis

Abstract

The invention relates to the technical field of oil product analysis, particularly provides a control method, a control module and an instrument for oil water content analysis, and aims to solve the problem that a conventional oil water content analyzer is relatively large in measurement deviation due to the influence of oil product temperature. In order to achieve the purpose, the control method for oil water content analysis comprises the steps that the oil product temperature T and the basic value of the oil product water content are obtained; determining the deviation value epsilon of the water content of the oil product according to the temperature of the oil product, wherein the deviation value epsilon of the water content of the oil product is the sum of at least one of the first temperature deviation value epsilon 1, the second temperature deviation value epsilon 2 and the third temperature deviation value epsilon 3; and according to the basic value of the water content of the oil product and the deviation value epsilon of the water content of the oil product, calculating to obtain a correction value of the water content of the oil According to the method, the deviation value caused by the oil product temperature to the oil product water content measurement is considered, so that correction is performed, the measurement deviation caused by the influence of the oil product temperature is reduced, and the accuracy of the final correction value of the oil product water content is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil analysis, and specifically provides a control method, a control module and an instrument for oil water analysis. Background Art

[0002] The water content of crude oil is an important parameter in the petrochemical industry. Detecting the water content of crude oil is a common concern in the processes of crude oil extraction, dehydration, processing, gathering and transportation, storage, transportation and sales, and oil refining. With the gradual development of automation technology, the detection method has gradually upgraded from manual sampling and testing to automated oil water content analyzers.

[0003] The current oil-water analyzer has a certain degree of detection accuracy, but it is still affected by the crude oil temperature and has measurement deviations. For some links that do not have strict requirements on crude oil quality (such as metering, etc.), the measurement deviation is within an acceptable range. However, for some refining processes that have very strict requirements on crude oil quality, the current oil-water analyzer has a large measurement deviation that will affect the refining process.

[0004] Therefore, there is an urgent need for an oil-water analyzer and a control method to solve the problem that the current oil-water analyzer has a large measurement deviation due to the influence of oil temperature. Summary of the invention

[0005] The present invention aims to solve the above technical problem, that is, to solve the problem that the existing oil-water analyzer has a large measurement deviation due to the influence of oil temperature.

[0006] In a first aspect, the present invention provides a control method for oil-water analysis, comprising: obtaining a basic value of an oil temperature T and an oil water content; determining an offset value ε of the oil water content according to the oil temperature, the offset value ε of the oil water content being the sum of at least one of a first temperature offset value ε1, a second temperature offset value ε2 and a third temperature offset value ε3; wherein the first temperature offset value is ε1=A1×(T-C1)+B1, and A1, B1 and C1 are constants; the second temperature offset value is ε2=A2×(T-C2)²+B2×(T-C2)+D2, and A2, B2, C2 and D2 are constants; the third temperature offset value is ε3=A3×(T-C3)²+B3×(T-C3)+D3, and A3, B3, C3 and D3 are constants; and obtaining a corrected value of the oil water content according to the basic value of the oil water content and the offset value ε of the oil water content.

[0007] By adopting the above technical features, the control method of oil water content analysis takes into account the offset value caused by the oil temperature on the oil water content measurement, and corrects it, reducing the measurement deviation caused by the influence of oil temperature, so as to improve the accuracy of the final corrected value of the oil water content.

[0008] In a specific implementation of the above-mentioned control method for oil-water analysis, A1=0.4235, B1=14.7721, C1=20; and / or, A2=0.1569, B2=-1.8631, C2=20, D2=10.3369; and / or, A3=0.0982, B3=-3.8697, C3=20, D3=39.1465.

[0009] In a specific implementation of the above-mentioned control method for oil-water content analysis, a correction value of the oil water content is calculated based on the basic value of the oil water content and the offset value ε of the oil water content, including: the correction value of the oil water content is the sum of the basic value of the oil water content and the offset value ε of the oil water content.

[0010] In a specific implementation of the above-mentioned control method for oil-water analysis, obtaining the basic value of the water content of the oil product includes: sending pulses with a set transmission frequency; receiving pulses transmitted by the oil product and obtaining the receiving frequency; and obtaining the basic value of the water content of the oil product based on the transmission frequency and the receiving frequency.

[0011] In a second aspect, the present invention provides a control module for oil-water analysis, which is used to implement the above-mentioned control method for oil-water analysis, including: an acquisition unit, used to acquire the oil temperature T; a storage unit, used to store the basic value of the oil water content; a first calculation unit, used to calculate the offset value ε of the oil water content according to the oil temperature T; a second calculation unit, used to calculate the correction value of the oil water content according to the offset value ε of the oil water content and the basic value of the oil water content.

[0012] In a third aspect, the present invention provides an oil-water analyzer, comprising: the above-mentioned control module; a detection sensor, placed in the oil product, configured to emit pulses of a set transmission frequency and capable of receiving pulses transmitted through the oil product to obtain a receiving frequency.

[0013] In a specific embodiment of the above-mentioned oil-water analyzer, the detection sensor includes a sensor body, a sensor base and a protective tube, the sensor body and the protective tube are both connected to the sensor base, and the protective tube is sleeved on the outside of the sensor body.

[0014] In a specific implementation of the above-mentioned oil-water analyzer, the detection sensor is a capacitive sensor.

[0015] In a specific embodiment of the above-mentioned oil-water analyzer, it also includes: a fixing plate, which is detachably connected to the detection sensor; a connecting pipe, which is connected to the fixing plate and can be used for wiring; and a display head, which is connected to the end of the connecting pipe away from the fixing plate.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The control method for oil water content analysis provided by the present invention includes: obtaining the basic values ​​of oil temperature T and oil water content; determining the offset value ε of the oil water content according to the oil temperature, the offset value ε of the oil water content being the sum of at least one of the first temperature offset value ε1, the second temperature offset value ε2 and the third temperature offset value ε3; wherein the first temperature offset value is ε1=A1×(T-C1)+B1, and A1, B1 and C1 are constants; the second temperature offset value is ε2=A2×(T-C2)²+B2×(T-C2)+D2, and A2, B2, C2 and D2 are constants; the third temperature offset value is ε3=A3×(T-C3)²+B3×(T-C3)+D3, and A3, B3, C3 and D3 are constants; and obtaining the corrected value of the oil water content according to the basic value of the oil water content and the offset value ε of the oil water content. The present invention takes into account the offset value caused by the oil temperature on the measurement of the water content of the oil, and makes corrections therefor, thereby reducing the measurement deviation caused by the influence of the oil temperature, so as to improve the accuracy of the final correction value of the water content of the oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which: Figure 1 It is a flow chart of the control method of oil water analysis provided by the present invention; Figure 2 is a cross-sectional view of the oil-water analyzer provided by the present invention; Figure 3 It is a cross-sectional view of a pipeline in the oil-water analyzer provided by the present invention; Figure 4 It is an explosion diagram of the oil-water analyzer provided by the present invention; Figure 5 It is a schematic diagram of the assembly of the detection sensor and the fixing plate in the oil-water analyzer provided by the present invention; Figure 6 It is an exploded view of the detection sensor and the fixing plate in the oil-water analyzer provided by the present invention.

[0018] Description of reference numerals: 1. Pipeline; 11. Fixing seat; 2. Detection sensor; 21. Probe center rod; 211. Limiting protrusion; 22. Sensor base; 221. Mounting groove; 222. Through hole; 23. Protective tube; 24. Locking nut; 25. Pressure ring; 26. Stopper; 3. Fixing plate; 31. Connecting tube; 32. First connecting piece; 4. Connecting tube; 41. Second connecting piece. DETAILED DESCRIPTION

[0019] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0020] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0021] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "setting", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate medium, or the internal connection of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] The water content of crude oil is an important parameter in the petrochemical industry. Detecting the water content of crude oil is a common concern in the processes of crude oil extraction, dehydration, processing, gathering and transportation, storage, transportation and sales, and oil refining. With the gradual development of automation technology, the detection method has gradually upgraded from manual sampling and testing to automated oil water content analyzers.

[0023] The oil water content analyzer currently using radio frequency microwave to measure the water content of oil products includes a detection sensor, which is arranged inside the pipeline. The applicant has found that as the temperature of the oil product changes, the measured water content of the oil product will have a slight deviation, resulting in measurement errors and low accuracy.

[0024] Based on this, Figure 1 As shown, the present invention provides a control method for oil-water analysis, comprising: S1. Obtaining basic values ​​of oil product temperature T and oil product water content. The oil product temperature T may be obtained by using a temperature sensor disposed in the oil product.

[0025] Regarding the acquisition of the basic value of the water content of the oil product, in the embodiment of the present invention, a capacitive detection sensor is used to measure and obtain the basic value of the water content of the oil product, specifically including: S11, send out a pulse of set transmission frequency.

[0026] S12, receiving the pulse transmitted by the oil product and obtaining the receiving frequency.

[0027] S13. Obtain a basic value of the water content of the oil product according to the transmitting frequency and the receiving frequency.

[0028] Specifically, the detection sensor includes a transmitter and a receiver, a capacitor is formed between the transmitter and the receiver, and the medium filled in the middle is oil. The dielectric constant of oil is about 2.3, and the dielectric constant of water is 80. As the water content in the oil is different, the physical and electrical properties of the oil are different (that is, the dielectric constant of crude oil is different), and the capacitance formed between the transmitter and the receiver of the detection sensor is different. A pulse with a set transmission frequency is sent from the transmitter, and after passing through the capacitor formed by the transmitter and the receiver, the pulse can be received by the receiver. As the water content in the oil changes, the capacitance formed between the transmitter and the receiver will change, and the receiving frequency of the pulse received by the receiver will also change. In this way, when the shape and spacing of the transmitter and the receiver remain unchanged, the water content of the oil can be calculated based on the transmission frequency and the receiving frequency. When the transmission frequency remains unchanged, the functional relationship between the receiving frequency and the water content of the oil can be summarized and stored so as to quickly obtain the corresponding water content of the oil according to the receiving frequency.

[0029] The higher the accuracy of the capacitive sensor disclosed in the present invention, the higher the accuracy of the basic value of the measured water content of the oil product.

[0030] It should be specially noted that, regarding the acquisition of the basic value of the water content of oil products, although the present invention provides a solution for obtaining the basic value of the water content of oil products by measuring with a capacitive detection sensor, this does not mean that the method of obtaining the basic value of the water content of oil products of the present invention is limited to the above solution. In other possible implementations, those skilled in the art may also adopt other known methods to obtain the basic value of the water content of oil products, which should all be included in the scope of protection of the present invention.

[0031] S2. Determine the offset value ε of the water content of the oil product according to the oil product temperature T.

[0032] In the example of the present invention, the offset value ε of the water content of the oil product is the sum of the first temperature offset value ε1, the second temperature offset value ε2 and the third temperature offset value ε3. Among them, the first temperature offset value ε1 is the temperature offset of the measuring sensor itself, and the second temperature offset value ε2 is the temperature offset of the measured medium. Both can be attributed to the fact that the temperature change of the oil product will cause the thermal expansion and contraction of the components of the oil-water analyzer, thereby causing the measurement offset. The third temperature offset value ε3 is the temperature offset caused by the structure of the oil-water analyzer, which can be attributed to the fact that the temperature change of the oil product will affect the parameters (such as resistance, voltage, etc.) of the electronic devices in the oil-water analyzer, thereby causing the measurement offset.

[0033] Specifically, the first temperature offset value is ε1=A1×(T-C1)+B1, where A1, B1 and C1 are constants. For example, A1=0.4235, B1=14.7721, and C1=20.

[0034] The second temperature offset value is ε2=A2×(T-C2)²+B2×(T-C2)+D2, where A2, B2, C2 and D2 are constants. For example, A2=0.1569, B2=-1.8631, C2=20, D2=10.3369.

[0035] The third temperature offset value is ε3=A3×(T-C3)²+B3×(T-C3)+D3, where A3, B3, C3 and D3 are constants. For example, A3=0.0982, B3=-3.8697, C3=20, and D3=39.1465.

[0036] It should be noted that, in other possible implementations, according to different situations, the offset value ε of the water content of the oil product can also be the sum of at least one of the first temperature offset value ε1, the second temperature offset value ε2 and the third temperature offset value ε3. For example, ε is any one of ε1, ε2, and ε3; or, ε=ε1+ε2; or, ε=ε1+ε3; or, ε=ε2+ε3.

[0037] S3. Calculate and obtain a correction value of the water content of the oil product according to the basic value of the water content of the oil product and the offset value ε of the water content of the oil product. Specifically, the correction value of the water content of the oil product is the sum of the basic value of the water content of the oil product and the offset value ε of the water content of the oil product.

[0038] In summary, the control method for oil-water analysis provided by the present invention has at least the following advantages: (1) The offset value caused by oil temperature on the measurement of oil water content is taken into account and corrected, reducing the measurement deviation caused by the influence of oil temperature, so as to improve the accuracy of the final correction value of oil water content; (2) Use capacitive detection sensors to accurately obtain the basic value of the oil water content, thereby improving the accuracy of the final correction value of the oil water content.

[0039] The present invention also provides a control module for oil-water analysis, which is used to implement the above-mentioned control method for oil-water analysis. The control module includes: An acquisition unit, used to acquire the oil temperature T; A storage unit, used to store the basic value of the water content of the oil; The first calculation unit is used to calculate the offset value ε of the water content of the oil product according to the oil product temperature T; The second calculation unit is used to calculate a correction value of the water content of the oil product according to a basic value of the water content of the oil product and an offset value ε of the water content of the oil product.

[0040] The first calculation unit includes a first calculation subunit, a second calculation subunit and a third calculation subunit. The first calculation subunit is used to calculate a first offset value ε1 of the water content of the oil product according to the oil product temperature T, the second calculation subunit is used to calculate a second offset value ε2 of the water content of the oil product according to the oil product temperature T, and the third calculation subunit is used to calculate a third offset value ε3 of the water content of the oil product according to the oil product temperature T.

[0041] like Figures 2 to 4 As shown, the present invention also provides an oil-water analyzer, which is installed on a pipeline 1 and includes the above-mentioned oil-water analysis control module and a detection sensor 2. The detection sensor 2 is placed in the oil product and is used to detect the basic value of the water content of the oil product. It is configured to emit a pulse with a set transmission frequency and can receive a pulse transmitted by the oil product to obtain a receiving frequency. The pulse can be a voltage pulse or a mechanical vibration pulse.

[0042] like Figure 5 and Figure 6 As shown, in the example of the present invention, the detection sensor 2 is a capacitive sensor. Specifically, the detection sensor 2 includes a probe center rod 21, a sensor base 22 and a protective tube 23. The probe center rod 21 and the protective tube 23 are both connected to the sensor base 22, and the protective tube 23 is sleeved on the outside of the probe center rod 21. For example, the probe center rod 21 acts as a transmitter to transmit a voltage pulse of a set frequency, and the protective tube 23 acts as a receiver to receive the voltage pulse signal. A capacitor is formed between the probe center rod 21 and the protective tube 23. The capacitance value changes with the water content of the oil product. The frequency of the voltage pulse received by the protective tube 23 changes with the capacitance value. In this way, the water content of the oil product can be calculated based on the voltage pulse frequency measured by the protective tube 23. In addition, the protective tube 23 can also protect the probe center rod 21 and the medium diversion, reducing the impact on the probe center rod 21.

[0043] Of course, in other embodiments, the probe center rod 21 can also be used as a receiving part, and a transmitting part is set on the pipeline 1; or, a receiving part is set on the pipeline 1, and the probe center rod 21 is used as a transmitting part.

[0044] One end of the sensor base 22 is provided with a mounting groove 221, and a through hole 222 is provided at the bottom of the mounting groove 221. The first end of the probe center rod 21 is located in the mounting groove 221 and inserted into the through hole 222. A limiting protrusion 211 is provided on the outer wall of the probe center rod 21 close to the first end, and the limiting protrusion 211 is located in the mounting groove 221. The second end of the probe center rod 21 is sleeved with a locking nut 24 and a clamping ring 25, and the clamping ring 25 can abut against the limiting protrusion 211. The locking nut 24 can be threadedly connected with the inner wall of the mounting groove 221 to force the clamping ring 25 and the probe center rod 21 to approach the sensor base 22. The sheath is sleeved on the outer side of the probe center rod 21 and is threadedly connected with one end of the sensor base 22. In addition, a stopper 26 is provided in the through hole 222, and the first end of the probe center rod 21 passes through the stopper 26 and is inserted into the through hole 222, so that the stopper 26 is located between the sensor base 22 and the first end of the probe center rod 21, and the stopper 26 is used for buffering to avoid rigid contact between the probe center rod 21 and the sensor base 22.

[0045] In addition, a fixing seat 11 is provided on the side wall of the pipeline 1, and the surface of the fixing seat 11 is a plane. The oil product analysis instrument also includes a fixing plate 3, a connecting pipe 4 and a display head (not shown in the figure), the fixing plate 3 is fixed to the fixing seat 11 by a first connecting member 32 (such as a bolt), the sensor base 22 in the detection sensor 2 is fixed to the fixing plate 3 and placed in the pipeline 1, the connecting pipe 4 is connected to the fixing plate 3 and is located outside the pipeline 1, and the display head is connected to the end of the connecting pipe 4 away from the fixing plate 3.

[0046] like Figure 4 As shown, a connecting pipe 31 is provided at one end of the fixing seat 11 close to the connecting pipe 4, and a plurality of sealing rings (such as O-rings) are provided on the outer wall of the connecting pipe 31. The connecting pipe 4 is sleeved on the connecting pipe 31, and the sealing rings are used to seal the connecting pipe 4 and the connecting pipe 31. In addition, after the connecting pipe 4 and the connecting pipe 31 are sleeved, a second connecting member 41 (such as a pin or a bolt, etc.) is passed through the side walls of the connecting pipe 4 and the connecting pipe 31 to fix them.

[0047] like Figure 4 As shown, the sensor base 22, the fixing plate 3 and the connecting tube 4 are all provided with wiring channels for leading the wiring on the probe center rod 21 and the protective tube 23 to the circuit board and the display head.

[0048] In addition, the sensor base 22 and the fixing plate 3, the fixing plate 3 and the connecting pipe 4, and the fixing plate 3 and the fixing seat 11 are all connected in a detachable manner to facilitate regular maintenance of the oil analysis instrument and reduce maintenance costs.

[0049] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A control method for oil-water analysis, characterized in that: include: Obtain the basic values ​​of oil temperature T and oil water content; Determine an offset value ε of the water content of the oil product according to the oil product temperature, the offset value ε of the water content of the oil product being the sum of at least one of a first temperature offset value ε1, a second temperature offset value ε2 and a third temperature offset value ε3; wherein, the first temperature offset value is ε1=A1×(T-C1)+B1, and A1, B1 and C1 are constants; the second temperature offset value is ε2=A2×(T-C2)²+B2×(T-C2)+D2, and A2, B2, C2 and D2 are constants; the third temperature offset value is ε3=A3×(T-C3)²+B3×(T-C3)+D3, and A3, B3, C3 and D3 are constants; The corrected value of the water content of the oil product is obtained by calculation according to the basic value of the water content of the oil product and the offset value ε of the water content of the oil product.

2. The control method for oil-water analysis according to claim 1, characterized in that: A1=0.4235, B1=14.7721, C1=20; and / or, A2=0.1569, B2=-1.8631, C2=20, D2=10.3369; and / or, A3=0.0982, B3=-3.8697, C3=20, D3=39.1465.

3. The control method for oil-water analysis according to claim 1, characterized in that: The correction value of the water content of the oil product is calculated according to the basic value of the water content of the oil product and the offset value ε of the water content of the oil product, including: The correction value of the water content of the oil product is the sum of the basic value of the water content of the oil product and the offset value ε of the water content of the oil product.

4. The control method for oil-water analysis according to claim 1, characterized in that: Obtain the basic value of oil water content, including: Send out pulses of set transmission frequency; Receive the pulse transmitted by the oil and obtain the receiving frequency; The basic value of the water content in the oil is obtained based on the transmitting frequency and the receiving frequency.

5. A control module for oil-water analysis, characterized in that: A control method for implementing the oil-water analysis according to any one of claims 1 to 4, comprising: An acquisition unit, used to acquire the oil temperature T; A storage unit, used to store the basic value of the water content of the oil; A first calculation unit, used for calculating an offset value ε of the water content of the oil product according to the oil product temperature T; The second calculation unit is used to calculate a correction value of the water content of the oil product according to the offset value ε of the water content of the oil product and the basic value of the water content of the oil product.

6. An oil-water analyzer, characterized in that: include: The control module as claimed in claim 5; The detection sensor (2) is placed in the oil product and is configured to emit pulses of a set transmission frequency and to receive pulses transmitted through the oil product to obtain a receiving frequency.

7. The oil-water analyzer according to claim 6, characterized in that: The detection sensor (2) comprises a probe center rod (21), a sensor base (22) and a protective tube (23); the probe center rod (21) and the protective tube (23) are both connected to the sensor base (22), and the protective tube (23) is sleeved on the outside of the probe center rod (21).

8. The oil-water analyzer according to claim 7, characterized in that: The detection sensor (2) is a capacitive sensor.

9. The oil-water analyzer according to claim 6, characterized in that: Also includes: A fixing plate (3) detachably connected to the detection sensor (2); A connecting pipe (4) connected to the fixing plate (3) and capable of being used for wiring; A display meter is connected to an end of the connecting pipe (4) away from the fixing plate (3).

Images