CN106401547B - Coal bed gas mining method for regulating desorption diffusion - Google Patents
Coal bed gas mining method for regulating desorption diffusion Download PDFInfo
- Publication number
- CN106401547B CN106401547B CN201510450303.8A CN201510450303A CN106401547B CN 106401547 B CN106401547 B CN 106401547B CN 201510450303 A CN201510450303 A CN 201510450303A CN 106401547 B CN106401547 B CN 106401547B
- Authority
- CN
- China
- Prior art keywords
- pressure
- coal bed
- gas
- underground
- water level
- 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.)
- Expired - Fee Related
Links
- 239000003245 coal Substances 0.000 title claims abstract description 95
- 238000000034 method Methods 0.000 title claims abstract description 47
- 238000003795 desorption Methods 0.000 title claims abstract description 39
- 238000009792 diffusion process Methods 0.000 title claims abstract description 31
- 230000001105 regulatory effect Effects 0.000 title claims abstract description 19
- 238000005065 mining Methods 0.000 title description 6
- 238000004519 manufacturing process Methods 0.000 claims abstract description 53
- 238000004422 calculation algorithm Methods 0.000 claims abstract description 32
- 230000000694 effects Effects 0.000 claims abstract description 16
- 238000011161 development Methods 0.000 claims abstract description 15
- 230000000737 periodic effect Effects 0.000 claims abstract description 13
- 238000005516 engineering process Methods 0.000 claims abstract description 10
- 230000009471 action Effects 0.000 claims abstract description 8
- 239000011159 matrix material Substances 0.000 claims abstract description 5
- 230000015572 biosynthetic process Effects 0.000 claims abstract 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 110
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 26
- 238000005086 pumping Methods 0.000 claims description 22
- 239000007788 liquid Substances 0.000 claims description 20
- 230000001276 controlling effect Effects 0.000 claims description 17
- 230000005540 biological transmission Effects 0.000 claims description 11
- 230000008859 change Effects 0.000 claims description 11
- 230000007704 transition Effects 0.000 claims description 10
- 238000004891 communication Methods 0.000 claims description 9
- 238000000605 extraction Methods 0.000 claims description 7
- 230000003213 activating effect Effects 0.000 claims description 6
- 238000004364 calculation method Methods 0.000 claims description 6
- 239000012530 fluid Substances 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 6
- 238000012544 monitoring process Methods 0.000 claims description 5
- 230000008901 benefit Effects 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 4
- 238000012546 transfer Methods 0.000 claims description 4
- 238000004458 analytical method Methods 0.000 claims description 3
- 230000006870 function Effects 0.000 claims description 3
- 238000011084 recovery Methods 0.000 claims description 3
- 238000009530 blood pressure measurement Methods 0.000 claims description 2
- 238000012790 confirmation Methods 0.000 claims description 2
- 238000009826 distribution Methods 0.000 claims description 2
- 238000004146 energy storage Methods 0.000 claims description 2
- 238000011156 evaluation Methods 0.000 claims description 2
- 238000002474 experimental method Methods 0.000 claims description 2
- 230000010354 integration Effects 0.000 claims description 2
- 238000012886 linear function Methods 0.000 claims description 2
- 238000002715 modification method Methods 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 230000004044 response Effects 0.000 claims description 2
- 230000033764 rhythmic process Effects 0.000 claims description 2
- 239000004576 sand Substances 0.000 claims description 2
- 239000010865 sewage Substances 0.000 claims description 2
- 230000006835 compression Effects 0.000 claims 2
- 238000007906 compression Methods 0.000 claims 2
- 230000008602 contraction Effects 0.000 claims 1
- 230000035485 pulse pressure Effects 0.000 claims 1
- 238000007670 refining Methods 0.000 abstract 1
- 238000006073 displacement reaction Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 230000005012 migration Effects 0.000 description 2
- 238000013508 migration Methods 0.000 description 2
- 238000012502 risk assessment Methods 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000002844 continuous effect Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000008398 formation water Substances 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000010349 pulsation Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000011426 transformation method Methods 0.000 description 1
Images
Landscapes
- Flow Control (AREA)
Abstract
A low-cost high-efficiency coal bed gas development solution method including a coal bed gas desorption and diffusion regulation method comprises three parts, namely wellhead equipment, a remote control system and a system control algorithm, wherein N wells are integrated to form a network, the whole gas production area is monitored and managed, modern technologies such as infrasonic waves, matrix control, big data and the like are comprehensively utilized, and the coal bed desorption and diffusion gas production in the area is integrally regulated and controlled to achieve the best effect. The well mouth equipment is controlled to produce gas at the frequency below the audible sound wave (including infrasonic wave), so that the pressure with certain period fluctuation is continuously applied to the coal bed in the gas production process, the coal bed microstructure generates periodic elastic shrinkage and relaxation micro deformation under the action of the force, different frequencies and unit integral driving schemes are changed, the desorption and diffusion characteristics of the refining unit are searched, the characteristics are tracked to find optimal period data, and the optimal period data are adopted to activate the formation energy, so that the aim of quickly producing the coal bed gas at low cost is fulfilled.
Description
Technical Field
The invention belongs to the technical field of underground energy exploitation, and particularly relates to an efficient coal bed methane exploitation method.
Background
The coal bed gas is a clean and environment-friendly energy source and is rich in reserves, however, from the development conditions of the two countries in the United states, the reserves which are easy to exploit are only about 10%, 90% of the coal bed gas belongs to the coal bed gas which is difficult to exploit, and if the coal bed gas is exploited as a resource, the technical problem of exploitation of the coal bed gas which is difficult to exploit must be solved.
The existing drainage and depressurization gas production process is completed by a process of desorption → diffusion → seepage → gas production which occurs in series, and the single well yield (the amount of coal bed gas which is transported from the inner part of a coal bed to a shaft in each day) depends on the slowest step in the first 3 steps.
For coal bed gas wells difficult to produce, after the initial drainage period, little or even no water is produced, and the gas production enters a relatively stable period, namely a low production period. For such coal seams, the seepage of free methane gas is not dominant in its migration, and desorption and diffusion are often the dominant factors in its migration. The difficult-to-produce coal bed gas is difficult to desorb and diffuse, other factors are not interfered, the completion of the two processes needs a long time, so that the single-well yield of the coal bed gas is low, and the currently adopted series production technology cannot directly regulate and control the main control factors to improve the single-well yield, so that the difficult-to-produce coal bed gas is not completely suitable for the coal bed gas development of the coal bed.
In order to recover the coal bed gas as soon as possible and complete desorption and diffusion, i.e. to discharge the water from the coal bed gas as much as possible, depressurize the coal bed gas and then accelerate desorption and seepage, many methods have been devised for this purpose, among them:
CN/201410511073.7 discloses a method for improving coal seam permeability by using a high-energy sound-electricity composite technology, which comprises the steps of injecting water into a drill hole and a drilled well, placing a sound-electricity composite operator at a specified position, enabling the operator to act as equipment such as the sound-electricity composite operator after repeated action of each section of the coal seam, and extracting the drill hole of the coal seam.
CN/201110027312.8 discloses a ground extraction coal bed gas well transformation method based on repetition frequency shock waves, which comprises the steps of continuously injecting underground water pumped and discharged from a local well or an adjacent well into a coal bed gas well to the height of a well mouth, sending underground equipment of a high energy-gathering high-power electric pulse device to the coal bed, carrying out repetition frequency shock wave treatment on the underground equipment of the electric pulse device at each operation point, pulling out the underground equipment after the treatment is finished, and putting the underground equipment into drainage and extraction.
The two methods have three problems, one is that the water injection of the low-pressure well can damage the output of the coal bed gas, the second is a short-term operation measure, the effective period is short even if the method is adopted under the environment of the high-pressure well, and the third problem is that the action distance of the high-pressure pulse is not far influenced by the gas absorption of the coal bed, so that the local coal bed is crushed into powder to cause difficulty in the subsequent gas production;
CN/201310114263.0 discloses a coal bed gas pressure reduction and extraction method and a device, a SY water ring vacuum compressor is adopted, the bottom hole flowing pressure is reduced by reducing the wellhead casing pressure, the desorption radius is increased, and the single well yield and the final recovery ratio are improved; a proper amount of water is filled in a machine body of the SY water ring vacuum compressor to be used as working liquid; when the impeller rotates, water is thrown to the periphery by the impeller, a central low-pressure area is formed under the action of centrifugal force, coal bed gas is sucked, the coal bed gas and the water enter the separator together, the separated gas enters the gas production pipeline, the water returns to the pump for recycling, and the gas in the well is continuously pumped out.
The method has three problems, one is that the water-ring vacuum pump system has low air extraction efficiency and high energy consumption, and is not necessarily reasonable economically, the other is that after a stable pressure difference is generated, partial desorption → diffusion → seepage channel is blocked and closed due to the increase of the pressure difference, and the third is that steam-water separation equipment is required to be arranged at a wellhead, so that the equipment investment is increased, and the energy consumption is also increased.
CN/201310697940.6 discloses a capillary pressure test system for coal bed gas, in order to prevent liquid in the well from entering a pressure transmission cylinder, a one-way constant pressure difference conduction valve is arranged at the bottom of the pressure transmission cylinder, if the downhole pressure is measured through the valve, only a fixed pressure difference needs to be added to the gas supply pressure, and the capillary pressure test system is a long-term pressure test monitoring system suitable for the production of a coal bed gas well.
The problems of the invention are: the constant pressure difference is only the nominal pressure difference of the valve opening, different pressure differences of the opening degree can change, if the purging airflow is small, the micro leakage of the valve meets the condition that the airflow does not generate the pressure difference when passing, and the pressure difference does not exist at the moment.
From the above analysis, there is no centralized mining solution for controlling desorption and diffusion of coal bed gas, which can not be achieved even by simply combining the existing inventions.
Disclosure of Invention
The invention aims to solve the existing problems, and aims to provide a comprehensive development solution with functions of regulating and controlling desorption and diffusion of coal bed gas, so as to achieve the aim of economically and efficiently exploiting the coal bed gas.
The storage and transport of coal bed gas in coal seams is quite complex, with most coal seams containing 80% to 90% methane in the micropores of the dense matrix of coal in an adsorbed state, and formation water mainly distributed in the cleats and cracks of the coal seam (generally not entering the micropores). The adsorbed methane is firstly desorbed from the solid microstructure of the coal to the surface to form free gas, then is diffused from the surface of the coal to the fine cracks, seeps to the large cracks in the fine cracks, then is seeped and moved to a shaft, and rises to the ground to form produced gas.
The invention provides a low-cost high-efficiency coal bed gas development solution method including a method for regulating and controlling desorption and diffusion of coal bed gas. The network can be a well at minimum and a coal bed gas geological structure unit at maximum, gas is produced at a frequency below audible sound waves (including infrasonic waves) by controlling wellhead equipment, so that the pressure with certain periodic fluctuation is continuously applied to a coal bed in gas production, a coal bed microstructure generates periodic elastic shrinkage relaxation micro deformation under the action of the force, desorption conditions are improved, pore channel enlargement communication is promoted, desorption and diffusion characteristics of an extraction unit are searched by changing different frequencies and a unit integral driving scheme, optimal periodic data are searched by tracking the characteristics, and stratum energy is activated by adopting the optimal periodic data, so that the aim of quickly producing the coal bed gas at low cost is fulfilled.
Well head equipment
The wellhead equipment includes but is not limited to an optimal water level control device arranged at a gas production wellhead, a wave generator, a control valve and a wellhead controller.
The optimal water level control device of the wellhead equipment comprises drainage equipment and an underground water level detection control device, and the optimal water level control device has two structures according to different underground environments:
one is a structure for directly detecting and controlling the water level by a buoyancy valve, and the structure is suitable for coal bed gas wells with little water or even without water sometimes. The drainage principle is that the hydraulic pump is connected with a motor through a pipeline to drive a water pump to drain water. The method is characterized in that: the ground is provided with a power pump, a buffer tank, a flowmeter, a filter and a transition water tank, and the underground is provided with a drainage pump driven by a hydraulic motor. The underground and the aboveground are connected by two pipelines which are respectively a power liquid pipeline and a drainage pipeline. The ground of the power liquid pipeline is connected with the outlet of the flowmeter, and the underground of the power liquid pipeline is connected with the inlet of the buoyancy valve; the ground of the drainage pipeline is connected with the transition water tank, and the ground is connected with the water outlet of the underground pump.
The transition water tank carries water produced from the well and has at least one inlet and two outlets. The inlet is the water drained by the underground drainage pump, and the water is firstly transferred into the transition water tank to be used as the source of the power liquid. The two outlets are: one outlet is a sewage draining outlet and a final water draining outlet for extracting underground water, and is arranged at the lower part in consideration of facilitating sand draining. In order to keep the water tank at a certain water level, the drainage control mode is completed by a buoyancy valve in the transitional water tank. The other outlet is clean water which is filtered by a filter to be the power liquid.
The filtered clean water is delivered to the inlet of a power pump, the outlet of the power pump is connected with a buffer tank, the outlet of the buffer tank is connected with a flow meter, and the flow meter is connected with a power liquid pipeline leading to the underground. The pressure of the power pump is pumped into a buffer tank which is sealed and provided with a pressure instrument, the buffer tank is used as an energy storage element between the power pump and the underground motor, certain pressure is kept, and the start and stop of the power pump are controlled according to the pressure of the buffer tank.
Since the hydraulic motor and the positive displacement drain pump are a unit, the motor drives the pump to drain the groundwater. When the underground water level is lowered, the buoyancy valve is closed to reduce the pumping speed, and when the water level is raised, the buoyancy valve is opened to increase the drainage speed. Because the motor and the water pump are both positive displacement connectors with relatively fixed movement tracks, and the volume of the motor and the volume of the water pump are in a fixed proportion, the instantaneous flow of the ground power liquid flow meter is a linear function of the drainage speed of the underground water level, and the underground water level and the water yield are known after the flow is known. The buoyancy valve controls the entering amount of power water, the water level is high, the underground pump pumps quickly, and the control valve is closed completely when no water exists, so that the optimal control of the underground water level is realized.
Another downhole water level control structure monitors the water level by a capillary pressure measuring device and then controls the rate of drainage. The method is characterized in that: the ground part of the pressure measuring device is provided with an air source which is connected with a pressure transmitting cylinder with a buoyancy valve underground through a throttling device and a capillary tube. Meanwhile, on the ground, the downhole capillary is also connected with the positive pressure end of a differential pressure transmitter (sensor), and the negative pressure end of the transmitter (sensor) is connected with the pressure of the sleeve. The buoyancy valve is arranged in the underground pressure transmission cylinder, and the air inlet valve is closed when the buoyancy valve enters liquid in the pressure transmission cylinder, so that liquid cannot enter the pressure measurement capillary. When the underground water level sensor works normally, an air source (any gas) with the pressure on the ground higher than the underground pressure outputs a tiny uninterrupted air flow through a throttling device, the air flow enters an underground pressure transfer cylinder through a capillary tube, water in the pressure transfer cylinder is discharged and then enters underground liquid, the pressure of the capillary tube is measured from the ground, the pressure is subtracted by the pressure of a sleeve and then multiplied by the density of the underground fluid, the underground water level is obtained, and therefore the water discharging speed can be controlled according to the water level monitoring condition.
The wave generator in the wellhead equipment is coal bed gas pumping and compressing equipment, which is an execution unit for generating pressure fluctuation in the system, and a certain gas production fluctuation curve can be generated by controlling the running rhythm speed of the gas pumping and compressing equipment by a control algorithm. The gas pumping and compressing device can be a turbine type device or a positive displacement type device.
The control valve in the wellhead equipment is a pipeline fluid circulation control actuator, can be opened and closed by receiving a control signal, and aims to match the action of a wave generator, prevent produced gas from flowing backwards and reduce gas production and drainage resistance loss.
The wellhead controller in the wellhead equipment can be a general electrical control device, and can also be an intelligent programmable equipment, such as a relay equipment combination, a PLC, an RTU, a singlechip, a computer or some combination thereof. The selection principle of the combination condition is determined according to the used target requirement, for example, the simplest relay equipment combination is selected only by simple control of a single well, and if complex comprehensive utilization of a big data technology and overall regulation and control of a matrix control technology are required, the configuration with a network communication control function is adopted.
Second, remote control system
The invention relates to a coal bed gas mining method for regulating desorption diffusion, wherein a remote control system comprises a generalized computer (such as a database, a server, a client terminal and communication switching network equipment thereof) and the like or a combination of the generalized computer, the server, the client terminal and the communication switching network equipment. The remote control system needs to be built with a certain foresight, and simultaneously, the principles of reliability, meeting the requirements and being economical and practical are considered.
Third, system control algorithm
The invention relates to a coal bed gas exploitation method for regulating desorption diffusion, wherein a system control algorithm comprises a drainage control algorithm and an optimal gas exploitation control algorithm.
The drainage control algorithm analyzes the causes of the rapid rise in water level that may occur in addition to the conventional downhole water level control to determine a reasonable drainage rate. The analysis of the reason for the rapid rise of the water level is to compile various reasons and a response plan in advance, quantify and queue various possible factors, incorporate monitoring data (water level change rate, gas production change rate) and preset data (geological original data and risk assessment data) into a unified algorithm, and finally obtain a control conclusion. The algorithm is characterized in that rules extracted from original data of a specific geological block, a specific gas production layout, a specific gas production well and a production process of the gas production well are used for finding out the influence degree of each rule on water level rise and the influence of drainage speed on coal bed stress (risk analysis) and gas production, the complete empirical data are incorporated into a unified calculation method compiled by the algorithm, and the algorithm is repeatedly modified to be in line with the actual development. The algorithm modification method comprises the following steps: and (3) arbitrarily intercepting certain section data of the development history, and substituting the section data into an algorithm to obtain a result with a basic coincidence rate not lower than an expected value (such as 85%). The original frame of the algorithm model is established by referring to relevant data according to the specific conditions of development geology and production of the coal bed gas, so that the integration of the actual conditions on site is avoided, and the final selection and confirmation of the calculation method are determined by the coincidence degree of the calculation control result and the objective actual rule.
The optimal gas production control algorithm is characterized in that the comprehensive economic benefit of expanding the desorption range, accelerating the desorption and diffusion speed and dredging the water-gas channel of the coal bed so as to increase the gas production effect by activating the energy of the coal bed by adopting the method is compared with the investment of achieving the same gas production effect by adopting other methods and prediction of the same gas production effect.
The invention relates to a coal bed gas exploitation method for regulating desorption diffusion, wherein the mode of activating stratum energy is to continuously supply fluctuating pressure with frequency below continuously fluctuating audible sound waves to a coal bed in the gas exploitation process so as to achieve the effects of regulating and controlling desorption and diffusion. The choice of the pulsation frequency should be based on the gas production effect, not only on the well, but also on the proximity of the well and the whole unit, where proximity is not necessarily a physical location, but on the magnitude of the effect.
The method for determining the maximum amplitude of the pressure change comprises the following steps: and starting wellhead equipment to extract coal bed gas, so that wellhead casing pressure is continuously reduced, and is not reduced when the wellhead casing pressure is reduced to a lower balance point, pumping is stopped at the moment, casing pressure can be automatically and gradually recovered, and pumping is started when the wellhead casing pressure is recovered to an upper balance point which is not increased, so that repeated circulation is realized, and the purposes of automatically tracking characteristics, searching for optimal periodic data and activating stratum energy by adopting the optimal periodic data are also realized. In the process, water drainage is taken care of, so that the underground water level is always kept below a reasonable water level line.
The frequency or waveform is adjusted by changing the pumping speed so that the frequency is higher when pumping is fast and is lower when pumping is fast. Similarly, to obtain a certain waveform, a speed regulation method may be used, for example, to obtain an output similar to a sine wave, a suction period should be determined based on a natural pressure recovery period, which is realized by means of speed regulation. To increase the frequency while maintaining the maximum amplitude of the pressure change, the pumping speed of the wellhead should be increased so that the cycle time is shortened, but the waveform is closer to the pulse wave. The sine wave transmission distance is farther, the pulse wave transmission distance is close, the period (frequency) is selected, which waveform is reasonable, how the multiple wells in the unit cooperate with each other is selected, and the waveform is determined by field experiment effects according to factors such as the nature of the coal bed and the distribution of the block structure well pattern. Experience should be gradually summarized in the production process using big data technology and turned into automatic learning and control programs to achieve efficient development of unit coal bed gas fields.
Description of the drawings:
description attached figure 1 is a schematic diagram of a structure for directly detecting and controlling water level through a buoyancy valve in the method for mining the coal bed methane by regulating and controlling desorption and diffusion.
In the figure: 1 is a down-hole positive displacement hydraulic drainage pump, and the upper part 2 is a water pump drainage pipeline; 3 is a transition water tank; 4 is a filter; 5 is a power pump; 6 is a buffer tank equipped with a pressure detection instrument; 7 is a pressure/differential pressure transmitter; 8 is a wellhead controller, 9 is a gas production flowmeter; 10 is a control valve; 11 is a wave generator; 12 is a flow meter; 13 is a downhole control water line; 14 is a power fluid conduit; 15 is a downhole buoyancy valve;
description attached figure 2 is a schematic diagram of controlling underground water level by a capillary pressure measuring mode in the coal bed methane exploitation method for regulating desorption diffusion.
In the figure: 7-12 have the same meaning as the mark of the first figure; 16 is a downhole pump and drain string; 17 is a pressure transmission cylinder with a buoyancy valve underground; 18 is an oil pumping machine (for pumping water, and can be other pumping equipment); and 19 is a gas source.
The specific implementation mode is as follows:
according to the coal bed gas exploitation method for regulating desorption diffusion, relevant implementation schemes are made according to the geological condition of the coal bed on site. A small number of experimental wells should be selected first for preliminary experimental evaluation and then be expanded gradually.
Before the test, the following characteristics should be fully considered:
1. because the frequency of the pressure wave is very low, the pressure wave can be transmitted very far in the coal bed, and the opportunity of wave trough superposition can be formed in the process that the microstructure of the coal bed absorbs the pressure wave, and the wave trough superposition can promote the desorption, the cutting and the expansion and the communication of cracks of the coal bed gas;
2. because the fluctuation pressure is very small compared with the conventional operation, only the elastic change of the microstructure can be formed, the stress damage of the natural structure of the coal bed can not be caused, and the coal bed is protected in the gas production process;
3. the fluctuation is formed by the operation mode of the gas production process, so that the fluctuation has long-term and continuous performance, and the continuous effect can make the coal bed gas communication area larger and larger;
4. the block is easy to be integrally controlled, so that the regulation and control scheme can be closely combined with the characteristics of the geological structure to achieve the best development effect;
5. the flexible adjustment scheme utilizes big data obtained by integral regulation and control and network communication, and can solve the optimal mining scheme by adopting an advanced algorithm and implement the scheme practically.
Claims (7)
1. A low-cost high-efficiency coal bed gas development solution method including a method for regulating and controlling desorption and diffusion of coal bed gas comprises three parts, namely well head equipment, a remote control system and a system control algorithm, wherein N wells are integrated to form a network, the whole gas production area is monitored and managed, modern technologies such as infrasonic waves, matrix control, big data and the like are comprehensively utilized, and the desorption and diffusion of the coal bed gas production in the area are integrally regulated and controlled to achieve the best effect; the network is a well at the minimum and a coal bed gas geological structure unit at the maximum, gas is extracted by controlling wellhead equipment at a frequency below an audible sound wave, so that the pressure with certain periodic fluctuation is continuously applied to a coal bed in gas extraction production, a coal bed microstructure generates periodic elastic contraction relaxation micro deformation under the action of the force, the desorption condition is improved, the pore channel is promoted to be enlarged and communicated, the desorption and diffusion characteristics of an extraction unit are searched and refined by changing different frequencies and a unit integral driving scheme, the characteristics are tracked to find optimal periodic data, and the optimal periodic data are adopted to activate formation energy, so that the aim of quickly extracting the coal bed gas at low cost is fulfilled;
the wellhead equipment comprises but is not limited to an optimal water level control device, a wave generator, a control valve and a wellhead controller which are arranged at a gas production wellhead;
the optimal water level control device comprises drainage equipment and an underground water level detection control device, and has two structures according to different underground environments:
the utility model provides a structure that is the buoyancy valve direct detection control water level, characterized by: the ground is provided with a power pump, a buffer tank, a flowmeter, a filter and a transition water tank, and a drainage pump driven by a hydraulic motor is arranged underground; the underground and the aboveground are connected by two pipelines which are respectively a power liquid pipeline and a drainage pipeline; the ground of the power liquid pipeline is connected with the outlet of the flowmeter, and the underground of the power liquid pipeline is connected with the inlet of the buoyancy valve; the ground of the drainage pipeline is connected with the transition water tank, and the underground of the drainage pipeline is connected with the drainage outlet of the drainage pump;
the transition water tank carries water produced from the underground and is provided with at least one inlet and two outlets; the inlet is the water discharged by the underground drainage pump, and the water is firstly transferred into the transition water tank and used as the source of the power liquid; the two outlets are: one outlet is a sewage discharge outlet and is also a final water discharge outlet for extracting underground water, and the outlet is arranged at the lower part in consideration of facilitating sand discharge; in order to keep the water tank at a certain water level, the drainage control mode is completed by a buoyancy valve in the transition water tank; the other outlet is clear water which is filtered by a filter to form power liquid;
delivering the filtered clear water to an inlet of a power pump, connecting an outlet of the power pump with a buffer tank, and connecting an outlet of the buffer tank with a flowmeter which is connected with a power fluid pipeline leading to the underground; pumping the pressurized gas into a buffer tank which is hermetically provided with a pressure instrument after being pressurized by a power pump, wherein the buffer tank is used as an energy storage element between the power pump and a downhole motor, keeping a certain pressure, and controlling the start and stop of the power pump according to the pressure of the buffer tank;
when the underground water level is lowered, the buoyancy valve is closed to reduce the pumping speed, and when the water level is raised, the buoyancy valve is opened to increase the drainage speed; because the motor and the drainage pump are both volumetric connectors with relatively fixed motion tracks, and the volumes of the motor and the drainage pump are in a fixed proportion, the instantaneous flow of the flow meter is a linear function of the drainage speed of the underground water level, and the flow is known, namely the underground water level and the water yield are known; the buoyancy valve controls the inlet amount of the power water, the water level is high, the drainage pump pumps quickly, and the control valve is closed completely when no water exists, so that the optimal control of the underground water level is realized;
the other underground water level control structure monitors the water level through a capillary pressure measuring device and then controls the drainage speed; the method is characterized in that: the ground part of the pressure measuring device is provided with an air source which is connected with a pressure transmitting cylinder with a buoyancy valve underground through a throttling device and a capillary tube; meanwhile, on the ground, the downhole capillary is also connected with the positive pressure end of a differential pressure transmitter, and the negative pressure end of the differential pressure transmitter is connected with the pressure of the sleeve; a buoyancy valve is arranged in the underground pressure transmission cylinder, and the air inlet valve is closed when the buoyancy valve enters liquid in the pressure transmission cylinder, so that liquid cannot enter the pressure measurement capillary; when the underground water level sensor works normally, an air source with the pressure on the ground higher than the underground pressure outputs a tiny uninterrupted airflow through a throttling device, the airflow enters an underground pressure transfer cylinder through a capillary tube, water in the pressure transfer cylinder is discharged and then enters underground liquid, the capillary tube pressure is measured from the ground, the pressure is subtracted by the casing pressure and then multiplied by the underground fluid density, the underground water level is obtained, and therefore the water drainage speed is controlled according to the water level monitoring condition.
2. The method for developing and solving the coalbed methane with low cost and high efficiency comprises the method for regulating and controlling desorption and diffusion of the coalbed methane according to claim 1, wherein the wave generator of the wellhead equipment is coalbed methane suction and compression equipment which is an execution unit for generating pressure fluctuation in a system, and a control algorithm controls the running rhythm speed of the gas suction and compression equipment to generate a certain gas production fluctuation curve; wherein the gas pumping and compressing device is a turbine type device or a volumetric type device.
3. The method for developing coalbed methane with low cost and high efficiency, comprising a method for regulating desorption and diffusion of coalbed methane according to claim 1, wherein the wellhead equipment is characterized in that: the control valve is a pipeline fluid circulation control actuator, can be opened and closed after receiving a control signal, and aims to match the action of a wave generator, prevent produced gas from flowing backwards and reduce resistance loss of gas production and drainage.
4. The method for developing and solving the coal bed gas with low cost and high efficiency comprising the method for regulating and controlling the desorption and diffusion of the coal bed gas as claimed in claim 1, wherein the wellhead controller is a general electric control device or an intelligent programmable device, such as a relay type device combination, a PLC, an RTU, a single chip microcomputer, a computer or some combination thereof; the selection principle of the combination condition is determined according to the used target requirement, for example, the simplest relay equipment combination is selected only by simple control of a single well, and if complex comprehensive utilization of a big data technology and overall regulation and control of a matrix control technology are required, the configuration with a network communication control function is adopted.
5. The method of claim 1, wherein the remote control system comprises a general computer, such as a database, a server, a client terminal, a communication switching network device thereof, or a combination thereof; the remote control system needs to be built with a certain foresight, and simultaneously, the principles of reliability, meeting the requirements and being economical and practical are considered.
6. The method of claim 1, wherein the system control algorithm comprises a drainage control algorithm and an optimal gas production control algorithm;
the drainage control algorithm analyzes the reason that the water level is likely to rise rapidly except the conventional control according to the underground water level so as to determine the reasonable drainage speed; the analysis of the reason for the rapid rise of the water level is to compile various reasons and a response plan in advance, and to quantitatively queue the various possible factors, the monitoring data is: water level change rate, gas production change rate and preset data: bringing the geological original data and the risk evaluation data into a unified algorithm, and finally obtaining a control conclusion; the algorithm is characterized in that rules extracted from original data of a specific geological block, a specific gas production layout, a specific gas production well and a production process of the gas production well are used for finding out the influence degree of each rule on water level rise and the influence of drainage speed on coal bed stress and gas production, the complete empirical data are incorporated into a unified calculation method compiled by the algorithm, and the algorithm is repeatedly modified to be in line with the actual development; the algorithm modification method comprises the following steps: arbitrarily intercepting certain section data of the development history, substituting the section data into an algorithm, and basically ensuring that the obtained result coincidence rate is not lower than an expected value; the original frame of the algorithm model is established by referring to relevant data according to the specific conditions of development geology and production of the coal bed gas, so that the integration of the actual conditions on site is avoided, and the final selection and confirmation of the calculation method are determined by the coincidence degree of the calculation control result and the objective actual rule;
the optimal gas production control algorithm is characterized in that the comprehensive economic benefit of activating the energy of the coal bed, expanding the desorption range, accelerating the desorption and diffusion speed and dredging the water-gas channel of the coal bed so as to increase the gas production effect is compared with the investment of achieving the same gas production effect by combining other methods and prediction of the comprehensive economic benefit.
7. The method for developing and solving the coalbed methane with low cost and high efficiency including the method for regulating and controlling desorption and diffusion of the coalbed methane according to claim 6, wherein the optimal gas production control algorithm is an algorithm for activating the energy of the coalbed, so as to expand the desorption range and accelerate the desorption and diffusion speed, and dredge the water-gas passage of the coalbed, so as to increase the comprehensive economic benefit of the gas production effect, and the pulse pressure with the frequency below the continuously downward fluctuating audible sound wave is continuously supplied to the coalbed in the gas production process, so that the effects of regulating and controlling the desorption and diffusion are achieved; the selection of the pulse frequency should be based on the gas production effect, which is not only on the well, but also on the adjacent well and the whole unit, where the adjacent well is not necessarily the physical location, and the impact size is used as the division;
the method for determining the maximum amplitude of the pressure change comprises the following steps: starting wellhead equipment to extract coal bed gas, so that wellhead casing pressure is continuously reduced, and is not reduced when the wellhead casing pressure is reduced to a lower balance point, pumping is stopped at the moment, casing pressure can be automatically and gradually recovered, and pumping is started when the wellhead casing pressure is recovered to be not increased, and the circulation is repeated, so that the purposes of automatically tracking characteristics, searching for optimal periodic data and activating stratum energy by adopting the optimal periodic data are achieved; in the process, water drainage is paid attention to, so that the underground water level is always kept below a reasonable water level line;
the method for adjusting the frequency or the waveform is to change the pumping speed, so that the frequency is high when the pumping speed is high, and the frequency is reduced when the pumping speed is low; similarly, in order to obtain a certain waveform, a speed regulation method is used, for example, to obtain an output approximate to a sine wave, a suction period is determined based on a pressure natural recovery period, which is realized by means of speed regulation; in order to increase the frequency while keeping the amplitude of the pressure change at a maximum, the pumping speed of the wellhead equipment should be increased, so that the period is shortened, but the waveform is closer to the pulse wave; the sine wave transmission distance is farther, the pulse wave transmission distance is close, the cycle frequency is large, which waveform is reasonable, how many wells in the unit cooperate with each other is selected, and the waveform is determined by field experiment effect according to factors such as the nature of the coal bed and the distribution of the block structure well pattern; experience should be gradually summarized in the production process using big data technology and turned into automatic learning and control programs to achieve efficient development of unit coal bed gas fields.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510450303.8A CN106401547B (en) | 2015-07-28 | 2015-07-28 | Coal bed gas mining method for regulating desorption diffusion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510450303.8A CN106401547B (en) | 2015-07-28 | 2015-07-28 | Coal bed gas mining method for regulating desorption diffusion |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106401547A CN106401547A (en) | 2017-02-15 |
| CN106401547B true CN106401547B (en) | 2021-06-25 |
Family
ID=58008725
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510450303.8A Expired - Fee Related CN106401547B (en) | 2015-07-28 | 2015-07-28 | Coal bed gas mining method for regulating desorption diffusion |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106401547B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111749644B (en) * | 2020-07-28 | 2023-07-21 | 山东安益矿用设备有限公司 | Device and method for dredging holes and cracks of coal seam gas extraction drill holes |
| CN114737928B (en) * | 2022-06-13 | 2022-09-06 | 中煤科工集团西安研究院有限公司 | Nuclear learning-based coalbed methane intelligent drainage and mining method and system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7246662B2 (en) * | 2004-03-30 | 2007-07-24 | Core Laboratories Canada Ltd | Systems and methods for controlling flow control devices |
| WO2007072172A1 (en) * | 2005-12-20 | 2007-06-28 | Schlumberger Technology B.V. | Method and system for development of hydrocarbon bearing formations including depressurization of gas hydrates |
| CN102182452B (en) * | 2011-04-28 | 2014-09-10 | 北京昊科航科技有限责任公司 | Capillary-type pressure measuring device |
| CN102373908B (en) * | 2011-10-08 | 2014-08-13 | 龚大建 | Underground ultrasonic yield-increasing pumping device for coalseam gas |
| CN103867147A (en) * | 2012-12-13 | 2014-06-18 | 中国石油天然气股份有限公司 | Coal bed gas well parallel pipe no-killing well coal powder discharging system |
| CN103527148B (en) * | 2013-09-26 | 2015-02-11 | 中煤科工集团西安研究院有限公司 | Technology and device for controlling pressure in layered mode and discharging and extracting oil in layer combined mode through double bushes and single pump |
| CN203947568U (en) * | 2014-06-24 | 2014-11-19 | 国网山东夏津县供电公司 | A kind of intelligent substation water drainage device |
-
2015
- 2015-07-28 CN CN201510450303.8A patent/CN106401547B/en not_active Expired - Fee Related
Non-Patent Citations (2)
| Title |
|---|
| 声波作用下煤体瓦斯解吸与放散特征研究;李建楼;《中国博士学位论文全文数据库工程科技Ⅰ辑》;20120531;全文 * |
| 大功率声波作用下煤层气吸附特性及其模型;姜勇东等;《煤炭学报》;20140531;第39卷;第152-157页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106401547A (en) | 2017-02-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101884163B (en) | Hydroelectric pumped-storage | |
| CN102839954B (en) | A kind of pressure pulse realizes the method for layering water distribution | |
| CN103998783A (en) | Horizontal and vertical well fluid pumping system | |
| CN103498648A (en) | Method and device for exploiting aquo-complex through combination of pressure reducing technology and hydraulic fracturing technology | |
| US20150060083A1 (en) | Systems and Methods for Artificial Lift Via a Downhole Piezoelectric Pump | |
| US8638004B2 (en) | Apparatus and method for producing electric power from injection of water into a downhole formation | |
| US11346186B2 (en) | Oil recovery tool and system | |
| RU2417306C1 (en) | Procedure for development of oil deposit | |
| CN105909228A (en) | Pulse high-pressure hydraulic slotting and fracturing device and method | |
| CN109057757B (en) | Natural gas hydrate exploitation method and device | |
| CN109882138A (en) | Self-flowing water injection oil replacement exploitation device and method | |
| CN106401547B (en) | Coal bed gas mining method for regulating desorption diffusion | |
| Sazonov et al. | Development of an automated compressor unit for gas compression at the periodic connection of an ejector | |
| CN207620776U (en) | Gas hydrates pilot production simulator | |
| CN211448630U (en) | Device for extracting natural gas hydrate by depressurization and double-pipe injection of modified fluid | |
| CN205955715U (en) | Pulsed high voltage water conservancy slot fracturing device | |
| CN113027387A (en) | Oil well interval pumping control system and method | |
| CN103470233A (en) | Heavy oil reservoir natural gas huff-puff oil production process system and oil production method | |
| CN106769756B (en) | Method for determining scale of water drainage with water and gas reservoirs in crack-pore type | |
| CN201835785U (en) | Oil-water well device capable of automatically controlling pressure relief and liquid discharge as well as pumping discharged liquid to production pipeline | |
| RU105938U1 (en) | DEVICE FOR FLUID PUMPING INTO A WELL | |
| CN109252840A (en) | Device and method based on the raising thin heavy oil recovery ratio that Gelled Foam on Production drives | |
| US11821293B2 (en) | Oil recovery tool and system | |
| CN206972212U (en) | A kind of double vibration source low-frequency high-power vibrational systems in underground | |
| CN208280912U (en) | Drilling apparatus and volume increase tubing string with it |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20210625 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |