CN112576235A - Oil and gas well sand production monitoring field noise elimination method - Google Patents
Oil and gas well sand production monitoring field noise elimination method Download PDFInfo
- Publication number
- CN112576235A CN112576235A CN201910947593.5A CN201910947593A CN112576235A CN 112576235 A CN112576235 A CN 112576235A CN 201910947593 A CN201910947593 A CN 201910947593A CN 112576235 A CN112576235 A CN 112576235A
- Authority
- CN
- China
- Prior art keywords
- noise
- sand production
- frequency
- oil
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000004576 sand Substances 0.000 title claims abstract description 122
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 111
- 238000012544 monitoring process Methods 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 title claims abstract description 41
- 230000008030 elimination Effects 0.000 title claims description 8
- 238000003379 elimination reaction Methods 0.000 title claims description 8
- 230000005540 biological transmission Effects 0.000 claims abstract description 20
- 238000001914 filtration Methods 0.000 claims abstract description 19
- 238000002834 transmittance Methods 0.000 claims abstract description 9
- 230000000737 periodic effect Effects 0.000 claims abstract description 4
- 230000033001 locomotion Effects 0.000 claims description 19
- 238000005086 pumping Methods 0.000 claims description 18
- 238000004364 calculation method Methods 0.000 claims description 16
- 239000012530 fluid Substances 0.000 claims description 11
- 238000012937 correction Methods 0.000 claims description 8
- 230000003116 impacting effect Effects 0.000 claims description 5
- 230000007423 decrease Effects 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 4
- 238000011084 recovery Methods 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims 1
- 238000005516 engineering process Methods 0.000 abstract description 6
- 230000015572 biosynthetic process Effects 0.000 description 6
- 238000000605 extraction Methods 0.000 description 6
- 239000000523 sample Substances 0.000 description 6
- 238000003786 synthesis reaction Methods 0.000 description 6
- 238000001514 detection method Methods 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 241001023788 Cyttus traversi Species 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000007781 pre-processing Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000002604 ultrasonography Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2218/00—Aspects of pattern recognition specially adapted for signal processing
- G06F2218/02—Preprocessing
- G06F2218/04—Denoising
Landscapes
- Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Geophysics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention provides a method for eliminating noise on a sand production monitoring site of an oil and gas well, which comprises the following steps: step 1, determining a noise signal by surveying a field; step 2, a sensor collects signals; step 3, calculating the transmission coefficient and energy transmittance of the ultrasonic noise to the medium, and analyzing the noise signal characteristics; step 4, removing low-frequency ultrasonic signals generated by the large machine through high-pass filtering; step 5, determining the time ratio of the sand production signal to the high-frequency noise according to the periodic characteristics of the signals; and 6, removing partial high-frequency noise through time-domain filtering, determining a calibration coefficient, and eliminating the noise influence superposed on the ultrasonic signal. The method for eliminating the field noise of the sand production monitoring of the oil and gas well solves the problems that the existing ultrasonic method sand production monitoring technology of the oil and gas well is influenced by field noise and has large monitoring error, and improves the accuracy of a sand production monitoring system.
Description
Technical Field
The invention relates to the technical field of oilfield development, in particular to a method for eliminating noise on a sand production monitoring site of an oil and gas well.
Background
The sand production of the oil and gas well is a phenomenon that sand grains are moved out of an oil layer along with fluid due to the fact that a sandstone structure near a perforation hole or in a bottom zone is damaged due to loose reservoir colloid, low strength and fluid scouring in the oil and gas production process. Frequently resulting in surface and downhole equipment erosion, casing damage, well abandonment, and a series of safety and environmental issues, so sand production needs to be mastered in order to take sand control measures. At present, sand production of oil and gas wells is monitored in real time mainly by an ultrasonic method so as to guide on-site safe production.
The ultrasonic method oil and gas well sand production monitoring technology has the technical principle that the sand carrying amount of produced liquid is explained by monitoring a well mouth ultrasonic signal, and the technology can be divided into a built-in type and an external type according to the installation mode of a sensor, wherein the former is invasive, and the latter is non-invasive. The invasive sensor is characterized in that a probe made of stainless steel material and a piezoelectric probe are inserted into fluid of a pipeline, solid particles carried in the fluid impact the probe of the sensor, the piezoelectric probe converts the probe into a high-frequency electric signal, the high-frequency electric signal is subjected to signal preprocessing such as filtering, amplification and detection, and then sand production information is obtained by using related signal processing technologies, so that the sand production condition of an oil well is judged. However, the built-in measurement method has a barrier effect on pipeline fluid, the service life of the probe is limited, the installation is complex, the time is not real, and the precision is not high.
The non-invasive sensor is installed in the outside of defeated oil pipe line, fasten in return bend twice pipe diameter department through anchor clamps, the sand grain is at the flow in-process of pipeline, the sand grain can collide the pipeline inner wall and produce ultrasonic signal when meetting the return bend, ultrasonic signal propagates along the pipe wall forward, external sensor detects out the sand signal, through charge amplifier, filter circuit, amplifier circuit, preprocessing circuit such as acquisition circuit after, transmit the transmission circuit again and transmit to the host computer and carry out data processing and corresponding calculation work, obtain information such as sand yield, sand output. The installation position of the external sand production detection method sensor is outside the pipeline, so the method is not suitable for sand production detection of the underground oil pipeline and is limited to sand production detection of the ground oil pipeline. The external sand production detection method has real-time performance, can detect the fluid with low sand content, and has important relation between the measurement of the sand content and the flow speed of the fluid, and when the flow speed of the fluid is small, the measured error is higher.
The existing ultrasonic method sand production monitoring technology for oil and gas wells is characterized in that ultrasonic signals generated by sand bodies impacting oil and gas well pipelines are collected, sand production quantity, sand production rate and other information of the oil and gas wells are obtained through algorithm calculation on the basis of the sand production signals, and noise in the collection process is corrected through standard deviation coefficients in calculation. But the factor correction cannot eliminate the noise effect on site through actual monitoring conditions of the oil production site. The coefficient correction can reduce the interference of white noise on a sand production signal, but the field condition is complex and the white noise is not the main noise influence, and an oil extraction field sensor can collect not only an ultrasonic signal generated by impacting a pipeline, but also noise generated by the operation of a field oil extraction machine. These noises can affect the sand production monitoring system and increase the error of the sand production monitoring system. Therefore, a novel method for eliminating noise on the sand production monitoring site of the oil and gas well is invented, and the technical problems are solved.
Disclosure of Invention
The invention aims to provide a method for eliminating noise on the sand production monitoring site of an oil and gas well, which solves the problems that the existing ultrasonic method sand production monitoring technology of the oil and gas well is influenced by site noise and has large monitoring error.
The object of the invention can be achieved by the following technical measures: the oil and gas well sand production monitoring field noise elimination method comprises the following steps: step 1, determining a noise signal by surveying a field; step 2, a sensor collects signals; step 3, calculating the transmission coefficient and energy transmittance of the ultrasonic noise to the medium, and analyzing the noise signal characteristics; step 4, removing low-frequency ultrasonic signals generated by the large machine through high-pass filtering; step 5, determining the time ratio of the sand production signal to the high-frequency noise according to the periodic characteristics of the signals; and 6, removing partial high-frequency noise through time-domain filtering, determining a calibration coefficient, and eliminating the noise influence superposed on the ultrasonic signal.
The object of the invention can also be achieved by the following technical measures:
in the step 1, through field survey, the noise is determined to mainly come from the oil pumping unit, the noise generated by the oil pumping unit is mainly divided into two parts, the first part is the noise generated when the oil pumping unit operates mechanically, and the characteristic of the noise shows that the amplitude is higher and the frequency is lower; the second part of noise is noise generated by friction of the sucker rod, and the characteristic of the noise is that the amplitude is low and the frequency is high; whether the noise signal is of high or low frequency is determined by surveying the site.
In step 2, detecting an ultrasonic signal generated by the sand body impacting the oil-gas well pipeline by using a sensor, and collecting the ultrasonic signal, wherein the ultrasonic signal is a sand production signal and a noise synthesis signal.
In step 3, according to the incident angle and the maximum critical angle when the sound wave propagates, the transmission coefficient and the energy transmittance of the ultrasonic noise to the medium are calculated, the relationship between the transmittance and the wall thickness of the pipe and the frequency of the sound wave signal is obtained, and then the frequency characteristic of the noise signal is analyzed.
In step 3, the transmission influence of the ultrasonic noise on the medium is determined through calculation, and the transmission coefficient W:
wherein
Obtained according to snell's law
It can be known that
Z1: medium 1 acoustic impedance; zl: medium 2 longitudinal wave acoustic impedance; zt: medium 2 shear wave acoustic impedance; θ: an angle of incidence of the sound wave; thetalThe refraction angle of longitudinal wave corresponding to the incident sound wave; thetatThe refraction angle of the transverse wave corresponding to the incident sound wave; rho1Medium 1 density; rho2Medium 2 density; v. of1 Medium 1 longitudinal wave sound velocity; v. ofl Medium 2 longitudinal wave sound velocity; v. oft Medium 2 transverse wave sound velocity; k is a radical ofly Medium 2 longitudinal wave number; k is a radical ofty Medium 2 transverse wave number; ω 2 pi f: ultrasonic angular frequency;
acoustic energy transmission
Under the condition that each acoustic parameter is constant, obtaining the relation between T ═ g (fd) and the transmissivity, the thickness of the tube wall and the frequency of the sound wave signal; the conclusion is as follows:
(1) the incident angle of the sound wave is within the maximum critical angle, and the transmissivity T is reduced along with the increase of the frequency and thickness product fd;
(2) the relationship between the frequency of the acoustic wave signal and the critical angle of incidence decreases as the incident frequency f increases.
In step 4, the noise of the mechanical motion is collected through the sensor, the frequency range of the low-frequency noise is determined, the capacitance value and the resistance value of the filter circuit are determined through a high-pass filter formula, and finally the built high-pass filter circuit is connected behind the ultrasonic sensor to filter the low-frequency noise collected by the sensor.
In step 5, the ratio of the duration time of the sand production signal to the duration time of the noise is obtained according to the change relation of the signal amplitude along with the monitoring time.
In step 6, the instantaneous sand production value of the oil-gas well is obtained through calculation of a formula (1) and a formula (2) on the basis of the acquired ultrasonic signals; determining the mathematical relationship between the sand production amount of the oil-gas well and the synthetic signal by a calibration method, determining a calibration coefficient C in a formula (2), and adjusting and eliminating the influence of noise on a sand production monitoring system by final calculation:
wherein Qg: air flow rate, unit: wanm3/d；Ql: liquid flow rate, unit: m is3D; d: pipe diameter, unit: mm; v: fluid flow rate, unit: m/s; s: instantaneous sand yield, unit: g; y: originally collecting data; σ: the standard deviation of the original data; n: fitting values of the original data; k: a standard deviation correction factor; c: correction coefficient, unit:gm2/s2。
the method for eliminating the noise on the sand production monitoring site of the oil and gas well determines the signal characteristic of the noise by analyzing the noise condition of the sand production monitoring site. And then, filtering the field ultrasonic noise collected by the sensor by utilizing the time domain and frequency domain combined filtering, wherein the filtered signal also contains noise, and the noise is calibrated by using a coefficient to eliminate the influence, so that the accuracy of the sand production monitoring system is improved. Compared with the prior art, the invention has the following advantages:
1. the method focuses on the noise of an oil extraction site for the first time, and determines the influence of the site noise on sand production monitoring by researching an ultrasonic transmission principle.
2. And the noise of the oil extraction site is filtered by the combined filtering of the three modes. The method comprises the steps of filtering most of noise on site through filtering in a time domain and a frequency domain, and eliminating the noise influence superposed on a sand production signal by using a calibration method to improve the accuracy of a sand production monitoring system.
Drawings
FIG. 1 is a flow chart of one embodiment of a method of noise abatement in an oil and gas well sand production monitoring site of the present invention;
FIG. 2 is a schematic diagram of "regular" noise generation for a pumping unit in accordance with an embodiment of the present invention;
FIG. 3 is a schematic view of the sucker rod cycle of one embodiment of the present invention;
FIG. 4 is a schematic representation of an ultrasonic signal at a production site in an embodiment of the present invention.
Detailed Description
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
As shown in fig. 1, fig. 1 is a flow chart of the oil and gas well sand production monitoring field noise elimination method of the invention: the high-frequency noise generated by the sucker rod and the sand production signal have higher similarity, and the influence on the sand production signal is more serious. For low-frequency signals, acquiring noise of mechanical motion through a sensor to determine the frequency range of the low-frequency noise, determining the capacitance value and the resistance value of a filter circuit through a high-pass filter formula, and finally connecting the built high-pass filter circuit behind an ultrasonic sensor to filter the low-frequency noise acquired by the sensor; for the high-frequency signals, the sand production signals appear regularly and periodically, the high-frequency noise generated by friction of the sucker rod is continuous, the sand production monitoring system is controlled by adopting a certain trigger mechanism through analyzing the ratio of the sand production signal duration time to the noise duration time, the monitoring system is ensured to only collect the ultrasonic signals containing the sand production signals, and the pure noise part is not collected, so that most of the noise can be filtered out from the time domain. Under the condition that time domain and frequency domain filtering cannot be achieved, because the ultrasonic signals collected by the oil and gas well sand production online monitoring system are sand production signals and noise synthesis signals, the characteristics of noise parts are stable, the mathematical relationship between the oil and gas well sand production amount and the synthesis signals is determined through a calibration method, a calibration coefficient is determined, and the influence of noise on the sand production monitoring system is eliminated through final calculation and adjustment. The specific implementation steps are as follows:
the noise signal is determined by surveying the site, step 101.
During oil extraction, the belt pulley drives the balance block to do circular motion, then the balance block transmits the circular motion to the walking beam through the connecting rod, so that the horse head connected with the walking beam does circular reciprocating up-and-down motion, and finally the up-and-down motion of the horse head drives the oil pumping rod to pump oil gas resources to the ground to complete oil extraction operation, see figure 2.
The mechanical motion in the field generates huge noise, and the frequency range of the noise is wide and extends from low frequency to high frequency. The generated noise is transmitted through air, and then part of the noise is transmitted into the steel pipeline and superposed with the sand production signal, so that the sand production monitoring is influenced.
Through site survey, the noise mainly comes from the pumping unit, and the noise generated by the pumping unit can be mainly divided into two parts, (1) the first part is the noise generated when the pumping unit operates mechanically, and the characteristic of the noise shows that the amplitude is higher and the frequency is lower; (2) the second part of noise is noise generated by friction of the sucker rod, and the characteristic of the noise is that the amplitude is low and the frequency is high. Whether the noise signal is of high or low frequency can be determined by surveying the field.
Step 102, a sensor collects a signal.
The ultrasonic signals generated by the sand impacting the oil-gas well pipeline are detected by a sensor and collected, and the ultrasonic signals are sand production signals and noise synthesis signals.
Step 103, obtaining the noise signal characteristics.
The mechanical motion in the field generates huge noise, and the frequency range of the noise is wide and extends from low frequency to high frequency. The generated noise is transmitted through air, and then part of the noise is transmitted into the steel pipeline and superposed with the sand production signal, so that the sand production monitoring is influenced. According to the incident angle and the maximum critical angle of the sound wave during propagation, the transmission coefficient and the energy transmittance of the ultrasonic noise to the medium are calculated, the relation between the transmittance and the wall thickness of the pipe and the frequency of the sound wave signal is obtained, and then the frequency characteristic of the noise signal is analyzed.
Taking a steel pipe at an oil production site as an example, when sound waves propagate in a steel plate, a first critical angle and a second critical angle exist, and the second critical angle is larger than the first critical angle. (1) If the incident angle of the sound wave is larger than the maximum critical angle and the transmission coefficient is 0, total reflection occurs; (2) if the sound wave incident angle is less than the maximum critical angle, there is a transmission problem, and we consider case (2).
The transmission coefficient W of the transmission influence of ultrasonic noise on the medium is determined by calculation
Wherein
Obtained according to snell's law
It can be known that
Z1: medium 1 acoustic impedance; zl: medium 2 longitudinal wave acoustic impedance; zt: medium 2 shear wave acoustic impedance; θ: an angle of incidence of the sound wave; thetalThe refraction angle of longitudinal wave corresponding to the incident sound wave; thetatThe refraction angle of the transverse wave corresponding to the incident sound wave; rho1 Medium 1 density; rho2 Medium 2 density; v. of1 Medium 1 longitudinal wave sound velocity; v. ofl Medium 2 longitudinal wave sound velocity; v. oft Medium 2 transverse wave sound velocity; k is a radical ofly Medium 2 longitudinal wave number; k is a radical ofty Medium 2 transverse wave number; ω 2 pi f: ultrasonic angular frequency.
Acoustic energy transmission
Under the condition that each acoustic parameter is constant, the relation between T ═ g (fd) and the transmissivity, the thickness of the tube wall and the frequency of the sound wave signal is obtained. The conclusion is as follows:
(1) the acoustic incident angle is within the maximum critical angle and the transmission T decreases as the frequency-to-thickness product fd increases.
(2) The relationship between the frequency of the acoustic wave signal and the critical angle of incidence decreases as the incident frequency f increases.
From the above conclusions, it can be seen that ultrasound noise is present in the field, the lower the frequency, the more transmitted into the pipe, and the higher the frequency, the less transmitted into the pipe. Therefore, both high-frequency noise and low-frequency noise can be more or less transmitted into the pipeline, and the sand production signal is influenced.
And 104, removing the low-frequency ultrasonic signals generated by the large machine by high-pass filtering.
Because the mechanical structure movement generates a noise signal with lower frequency and higher amplitude, and the sand production signal is basically a high-frequency ultrasonic signal, the noise generated by the mechanical movement and the sand production signal have larger discrimination on a frequency domain. A high pass filter may be used to filter out low frequency noise. The method specifically comprises the steps of collecting noise of mechanical motion through a sensor, determining the frequency range of low-frequency noise, determining the capacitance value and the resistance value of a filter circuit through a high-pass filter formula, and finally connecting the built high-pass filter circuit behind an ultrasonic sensor to filter the low-frequency noise collected by the sensor.
And 105, determining the time ratio of the sand production signal and the high-frequency noise according to the periodic characteristics of the signals.
Noise generated by friction of the sucker rod and a sand production signal have no great difference on frequency characteristics, so that the noise cannot be filtered by using only a low-pass or high-pass filter. By analyzing the motion principle of the pumping unit, the method tries to remove the noise generated by the friction of the sucker rod from the time domain. The working principle of the pumping unit is the principle of a connecting rod mechanism, and the pumping rod drives an oil pump piston to reciprocate up and down to pump oil in a lower layer out and send the oil to the ground. Therefore, in one motion cycle of the sucker rod, the pumping action only accounts for one part of the whole mechanical motion cycle of the sucker rod, the action of the sucker rod outside the pumping action is only the simple mechanical motion for the piston motion, and the motion cycle of the sucker rod is shown as the attached figure 3.
When the existing sand production monitoring system collects ultrasonic signals, all the ultrasonic signals are collected in an undifferentiated and full time domain. However, by analyzing the working principle of the pumping unit, the pumping rod is essentially all noise to meet the ultrasonic signal generated by the movement of the piston. The monitoring system also uses the noise as a sand production signal, which increases the value of the instantaneous sand production amount and causes errors of the sand production monitoring system. This portion of the noise needs to be filtered out first.
The sand production monitoring system was used to monitor the field signal, the ultrasound signal collected is shown in figure 4. In the figure, the ordinate is amplitude, the abscissa is time, the signal with prominent amplitude is a sand production signal, and the part with constant middle amplitude is high-frequency noise. As can be seen from the figure, the sand production signals appear regularly and periodically, the noise generated by the friction of the sucker rod is continuous, and the ratio of the sand production signal duration to the noise duration is obtained according to the change relation of the signal amplitude along with the monitoring time.
And 106, removing part of high-frequency noise through time-domain filtering, determining a calibration coefficient, and eliminating the noise influence superposed on the ultrasonic signal.
In actual sand production monitoring, a certain trigger mechanism is adopted to control a sand production monitoring system by analyzing the ratio of the sand production signal duration time to the noise duration time, so that the monitoring system is ensured to only collect ultrasonic signals containing sand production signals, and the pure noise part is not collected, so that most of noise can be filtered from the time domain.
The noise generated by the sucker rod exists in the whole time period, even most of noise signals can be filtered in the time domain, the sand production signals collected by the sensor still contain the noise, and the noise and the sand production signals are mixed and kept synchronous in the time domain and cannot be removed through time domain filtering. The frequency difference between the noise frequency generated by the friction of the sucker rod and the sand production signal is not large, and the frequency domain filtering can not be realized. Under the condition that time domain and frequency domain filtering cannot be realized, the method adopts a calibration method to eliminate the influence of noise on sand production calculation. Because the ultrasonic signals collected by the online sand production monitoring system of the oil and gas well are sand production signals and noise synthesis signals, the mathematical relationship between the sand production amount of the oil and gas well and the synthesis signals can be determined by a calibration method, a calibration coefficient is obtained, and the influence of noise on the sand production monitoring system is eliminated by final calculation and adjustment.
The analysis can find that the characteristics of the noise and the white noise generated by the sucker rod are quite similar, the frequency and the amplitude are stable, and the signal has no obvious change. The online monitoring system for sand production of the oil and gas well is used for obtaining the instantaneous sand production value of the oil and gas well through calculation of a formula (1) and a formula (2) on the basis of the acquired ultrasonic signals. The previous analysis revealed that the ultrasonic signal actually involved in the calculation was an ultrasonic signal obtained by synthesizing the sand production signal and the noise. But the noise part in the synthetic signal has stable characteristics, so the mathematical relationship between the sand production amount of the oil-gas well and the synthetic signal can be determined by a calibration method, the calibration coefficient C in the formula (2) is determined, and the influence of the noise on the sand production monitoring system is adjusted and eliminated by final calculation.
The above formula has three parameters, which are respectively data given on site, a value automatically obtained by a program and a calibration value self-obtained according to the site condition. Wherein Qg: air flow rate, unit: wanm3/d；Ql: liquid flow rate, unit: m is3D; d: pipe diameter, unit: mm; are all data provided at the oil recovery site. V: fluid flow rate, unit: m/s; s: instantaneous sand yield, unit: g; y: originally collecting data; σ: the standard deviation of the original data; n: fitting values of the original data; are all values that the program automatically finds. K: a standard deviation correction factor; c: correction coefficient, unit: gm2/s2. The calibration value is obtained according to the noise condition.
In conclusion, the denoising method provided by the invention can eliminate the influence of noise on the sand production monitoring system on the oil production site. In the process of filtering noise, the integrity of the sand production signal is kept to the maximum extent, and the accuracy of the sand production monitoring system can be effectively improved.
Claims (8)
1. The method for eliminating the noise on the sand production monitoring site of the oil and gas well is characterized by comprising the following steps of:
step 1, determining a noise signal by surveying a field;
step 2, a sensor collects signals;
step 3, calculating the transmission coefficient and energy transmittance of the ultrasonic noise to the medium, and analyzing the noise signal characteristics;
step 4, removing low-frequency ultrasonic signals generated by the large machine through high-pass filtering;
step 5, determining the time ratio of the sand production signal to the high-frequency noise according to the periodic characteristics of the signals;
and 6, removing partial high-frequency noise through time-domain filtering, determining a calibration coefficient, and eliminating the noise influence superposed on the ultrasonic signal.
2. The method for eliminating the noise on the sand production monitoring site of the oil and gas well as claimed in claim 1, wherein in the step 1, the noise is determined to be mainly from the oil pumping unit through site survey, the noise generated by the oil pumping unit is mainly divided into two parts, the first part is the noise generated when the oil pumping unit operates mechanically, and the noise is characterized by higher amplitude and lower frequency; the second part of noise is noise generated by friction of the sucker rod, and the characteristic of the noise is that the amplitude is low and the frequency is high; whether the noise signal is of high or low frequency is determined by surveying the site.
3. The method for eliminating the noise on the sand production monitoring site of the oil and gas well as recited in claim 1, wherein in the step 2, an ultrasonic signal generated by the sand body impacting the oil and gas well pipeline is detected by a sensor and collected, and the ultrasonic signal is a sand production signal and a noise composite signal.
4. The oil and gas well sand production monitoring field noise elimination method according to claim 1, characterized in that in step 3, according to the incident angle and the maximum critical angle when the sound wave propagates, the transmission coefficient and the energy transmittance of the ultrasonic noise to the medium are calculated, the relationship between the transmittance and the pipe wall thickness and the sound wave signal frequency is obtained, and then the frequency characteristic of the noise signal is analyzed.
5. The oil and gas well sand production monitoring field noise elimination method according to claim 4, characterized in that in step 3, the transmission influence of ultrasonic noise on the medium is determined by calculation, and the transmission coefficient W is:
wherein
Obtained according to snell's law
It can be known that
Z1: medium 1 acoustic impedance; zl: medium 2 longitudinal wave acoustic impedance; zt: medium 2 shear wave acoustic impedance; θ: an angle of incidence of the sound wave; thetalThe refraction angle of longitudinal wave corresponding to the incident sound wave; thetatThe refraction angle of the transverse wave corresponding to the incident sound wave; rho1Medium 1 density; rho2Medium 2 density; v. of1Medium 1 longitudinal wave sound velocity; v. oflMedium 2 longitudinal wave sound velocity; v. oftMedium 2 transverse wave sound velocity; k is a radical oflyMedium 2 longitudinal wave number; k is a radical oftyMedium 2 transverse wave number; ω 2 pi f: ultrasonic angular frequency;
acoustic energy transmission
Under the condition that each acoustic parameter is constant, obtaining the relation between T ═ g (fd) and the transmissivity, the thickness of the tube wall and the frequency of the sound wave signal; the conclusion is as follows:
(1) the incident angle of the sound wave is within the maximum critical angle, and the transmissivity T is reduced along with the increase of the frequency and thickness product fd;
(2) the relationship between the frequency of the acoustic wave signal and the critical angle of incidence decreases as the incident frequency f increases.
6. The oil and gas well sand production monitoring field noise elimination method according to claim 1, characterized in that in step 4, the noise of mechanical motion is collected through a sensor, the frequency range of low-frequency noise is determined, the capacitance value and the resistance value of the filter circuit are determined through a high-pass filter formula, and finally the built high-pass filter circuit is connected behind the ultrasonic sensor to filter the low-frequency noise collected by the sensor.
7. The method for eliminating noise on site during sand production monitoring of oil and gas wells as claimed in claim 1, wherein in step 5, the ratio of the sand production signal duration to the noise duration is obtained according to the variation of the signal amplitude with the monitoring time.
8. The oil and gas well sand production monitoring field noise elimination method according to claim 1, characterized in that in step 6, the instantaneous sand production value of the oil and gas well is obtained through calculation of formula (1) and formula (2) based on the acquired ultrasonic signals; determining the mathematical relationship between the sand production amount of the oil-gas well and the synthetic signal by a calibration method, determining a calibration coefficient C in a formula (2), and adjusting and eliminating the influence of noise on a sand production monitoring system by final calculation:
wherein Qg: air flow rate, unit: wanm3/d；Ql: liquid flow rate, unit: m is3D; d: pipe diameter, unit: mm; are all data provided at the oil recovery site. V: fluid flow rate, unit: m/s; s: instantaneous sand yield, unit: g; y: originally collecting data; σ: the standard deviation of the original data; n: fitting values of the original data; are all values that the program automatically finds. K: a standard deviation correction factor; c: correction coefficient, unit: gm2/s2。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910947593.5A CN112576235A (en) | 2019-09-30 | 2019-09-30 | Oil and gas well sand production monitoring field noise elimination method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910947593.5A CN112576235A (en) | 2019-09-30 | 2019-09-30 | Oil and gas well sand production monitoring field noise elimination method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112576235A true CN112576235A (en) | 2021-03-30 |
Family
ID=75117181
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910947593.5A Pending CN112576235A (en) | 2019-09-30 | 2019-09-30 | Oil and gas well sand production monitoring field noise elimination method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112576235A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106089188A (en) * | 2016-06-02 | 2016-11-09 | 中国石油大学(华东) | A kind of real-time minimizing technology of mud pulse signal pump noise |
| CN106368675A (en) * | 2016-08-29 | 2017-02-01 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Oil and gas well sand production monitor and sand production monitoring data processing method |
| CN109236272A (en) * | 2018-09-05 | 2019-01-18 | 南通晟霖格尔电子科技有限公司 | A kind of non-built-in mode heavy crude well sand production rate monitoring system and method |
-
2019
- 2019-09-30 CN CN201910947593.5A patent/CN112576235A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106089188A (en) * | 2016-06-02 | 2016-11-09 | 中国石油大学(华东) | A kind of real-time minimizing technology of mud pulse signal pump noise |
| CN106368675A (en) * | 2016-08-29 | 2017-02-01 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Oil and gas well sand production monitor and sand production monitoring data processing method |
| CN109236272A (en) * | 2018-09-05 | 2019-01-18 | 南通晟霖格尔电子科技有限公司 | A kind of non-built-in mode heavy crude well sand production rate monitoring system and method |
Non-Patent Citations (2)
| Title |
|---|
| 朱倩倩;党博;: "基于Labview的油气井出砂在线监测软件设计", 电子制作, no. 19, pages 74 - 75 * |
| 马英;李临华;郭林园;刘玉国;姜国良;: "排砂采油技术适应性分析", 特种油气藏, vol. 15, no. 04, pages 97 - 99 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10472957B2 (en) | Entropy based multiphase flow detection | |
| US10698427B2 (en) | System and method for assessing sand flow rate | |
| US9891335B2 (en) | Wireless logging of fluid filled boreholes | |
| RU2607826C2 (en) | Downhole tool for determining flow velocity | |
| US12055032B2 (en) | Flexural wave measurement for thick casings | |
| US20070019506A1 (en) | Ultrasonic Imaging In Wells Or Tubulars | |
| EA012154B1 (en) | Acoustic fluid analyzer | |
| CN104389586B (en) | The measuring method of fluid level depth of oil well measuring device | |
| EP3879311B1 (en) | Method for determining the integrity of a solid bonding between a casing and a wellbore | |
| CN103994796B (en) | The system for detecting the liquid in both acoustic flowmeters | |
| WO2016112147A1 (en) | Gauge length optimization in distributed vibration sensing | |
| US7069776B2 (en) | Method for measuring particle concentration during injection pumping operations | |
| CN107389786B (en) | A kind of gas incursion check signal processing method based on time domain | |
| WO2019040639A1 (en) | System and method for assessing sand flow rate | |
| Wang et al. | Research on comprehensive and effective acoustic signal processing methods for caculating downhole liquid level depth | |
| CN109188016B (en) | Acoustic-electric bimodal measurement method for phase-splitting flow velocity of oil-gas-water three-phase flow | |
| CN107389787A (en) | A kind of gas incursion check signal processing method based on frequency domain | |
| CN112576235A (en) | Oil and gas well sand production monitoring field noise elimination method | |
| US10961847B2 (en) | Acoustic flow meter tool and related methods | |
| CN115573697A (en) | Multiphase flow pipeline silt particle content and erosion monitoring and early warning device and method | |
| CN109541607B (en) | Multi-phase flow slug flow and mixed flow liquid film thickness distribution type ultrasonic measuring device | |
| Zhou et al. | Measurement of sound velocity in oil wells based on fast adaptive median filtering | |
| US20240167380A1 (en) | Analyzing drill cuttings using acoustic analysis | |
| Zhu et al. | Lost circulation detection method through transient pressure wave based on STA/LTA analysis | |
| CN118148614A (en) | Optical fiber on-line measuring system and method for downhole fluid production profile of oil well |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |