CN110424937A - Nitrogen-carbon dioxide combined transformation yield increasing method for low-yield well of coal bed gas - Google Patents
Nitrogen-carbon dioxide combined transformation yield increasing method for low-yield well of coal bed gas Download PDFInfo
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- 239000003245 coal Substances 0.000 title claims abstract description 42
- 238000000034 method Methods 0.000 title claims abstract description 25
- KPAMAAOTLJSEAR-UHFFFAOYSA-N [N].O=C=O Chemical compound [N].O=C=O KPAMAAOTLJSEAR-UHFFFAOYSA-N 0.000 title claims abstract description 17
- 230000009466 transformation Effects 0.000 title claims abstract description 11
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 120
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 115
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 87
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 60
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 60
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 53
- 239000007789 gas Substances 0.000 claims abstract description 17
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims description 38
- 239000007788 liquid Substances 0.000 claims description 19
- 238000012544 monitoring process Methods 0.000 claims description 16
- 230000000638 stimulation Effects 0.000 claims description 13
- 238000005422 blasting Methods 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 9
- 238000004458 analytical method Methods 0.000 claims description 5
- 238000004140 cleaning Methods 0.000 claims description 2
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 2
- 230000003631 expected effect Effects 0.000 claims description 2
- 239000012530 fluid Substances 0.000 claims description 2
- 230000003068 static effect Effects 0.000 claims 1
- 238000010276 construction Methods 0.000 abstract description 17
- 238000000605 extraction Methods 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 4
- 238000004364 calculation method Methods 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 description 8
- 238000011010 flushing procedure Methods 0.000 description 3
- 238000004880 explosion Methods 0.000 description 2
- 239000006260 foam Substances 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 229920002907 Guar gum Polymers 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 229960002154 guar gum Drugs 0.000 description 1
- 235000010417 guar gum Nutrition 0.000 description 1
- 239000000665 guar gum Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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- 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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/164—Injecting CO2 or carbonated water
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- 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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/166—Injecting a gaseous medium; Injecting a gaseous medium and a liquid medium
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- 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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/25—Methods for stimulating production
- E21B43/26—Methods for stimulating production by forming crevices or fractures
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Abstract
Description
技术领域technical field
本发明涉及一种煤层气低产井氮气-二氧化碳联合改造增产方法，属煤层气勘探开发技术领域。The invention relates to a nitrogen-carbon dioxide combined transformation and production increase method for coalbed methane low-production wells, belonging to the technical field of coalbed methane exploration and development.
背景技术Background technique
我国煤层气产业始于1996年中联煤层气公司的成立和运行。2003年晋城蓝焰煤层气公司在潘庄区块30口煤层气生产试验井的产量突破引导了中国煤层气的方向和步伐。到2014年底，我国已经完成煤层气钻井15000多口。但是我国煤层气开发仍然面临两个重大技术挑战。一是低渗透煤储层的有效的增产改造技术，二是生产衰竭低产井的增产改造技术。形成这一局面的地质与技术背景是，我国煤储层渗透率普遍偏低以及继而形成的煤层气井产量普遍偏低，平均单井日产700m3/d左右；二是早期的高产井逐步进入产量衰竭期，日产低于300m3/d的老井数量逐渐增加，目前预计至少5000口，低产井改造在中国煤层气行业具有探索和试验意义。my country's coalbed methane industry began in 1996 with the establishment and operation of China United Coalbed Methane Company. In 2003, the production breakthrough of Jincheng Lanyan Coalbed Methane Co., Ltd. in 30 coalbed methane production test wells in Panzhuang block guided the direction and pace of China's coalbed methane. By the end of 2014, more than 15,000 coalbed methane wells had been drilled in my country. However, my country's coalbed methane development still faces two major technical challenges. One is the effective stimulation technology for low-permeability coal reservoirs, and the other is the stimulation technology for production-depleted and low-yield wells. The geological and technical background for this situation is that the permeability of coal reservoirs in China is generally low and the production of coalbed methane wells formed thereafter is generally low, with an average daily production of about 700m 3 /d per well; During the depletion period, the number of old wells with a daily production of less than 300m 3 /d is gradually increasing, and it is currently estimated that there are at least 5,000 wells. The reconstruction of low-production wells has exploration and test significance in China's coalbed methane industry.
当前在对煤层气低产井进行二次增产改造时，常用的技术有常规水力压裂、氮气泡沫压裂、氮气泡沫压裂、活性水-氮气伴注压裂、胍胶压裂、滑溜水压裂等，这些常用技术都有优缺点，一方面对煤层污染二次污染性大；另一方面难以形成复杂裂缝，增产效果单一。Currently, the commonly used techniques for secondary stimulation of low-production CBM wells include conventional hydraulic fracturing, nitrogen foam fracturing, nitrogen foam fracturing, active water-nitrogen co-injection fracturing, guar gum fracturing, slippery hydraulic fracturing. These commonly used technologies have advantages and disadvantages. On the one hand, they cause secondary pollution to coal seam pollution; on the other hand, it is difficult to form complex cracks, and the effect of increasing production is single.
因此针对这一现状，迫切需要一种全新的煤层气低产井增产改造工艺，以满足煤层气开采工作的需要。Therefore, in view of this situation, there is an urgent need for a new stimulation technology for low-production coalbed methane wells to meet the needs of coalbed methane mining.
发明内容Contents of the invention
本发明目的就在于克服上述不足，提供一种煤层气低产井氮气-二氧化碳联合改造增产方法。The purpose of the present invention is to overcome the above-mentioned shortcomings, and provide a method for increasing the production of coalbed methane low-yield wells through nitrogen-carbon dioxide combined reformation.
为实现上述目的，本发明是通过以下技术方案来实现：To achieve the above object, the present invention is achieved through the following technical solutions:
S1，预制改造井孔，根据待改造煤层气井地质构造条件和历史排采数据，对该作业井进行通洗井作业；S1, prefabricate the wellbore for reconstruction, and carry out the well cleaning operation for the operating well according to the geological structure conditions and historical drainage data of the coalbed methane well to be reformed;
S2，预制设备和材料，根据作业井的煤层厚度、井径、煤层顶底板岩性等数据预制氮气压裂作业和二氧化碳气相压裂所需的设备和材料；S2, prefabricate equipment and materials, prefabricate the equipment and materials required for nitrogen fracturing operations and carbon dioxide gas phase fracturing according to the coal seam thickness, well diameter, coal seam roof and floor lithology and other data of the operating well;
S3，氮气压裂作业，即对作业井煤层段进行氮气压裂作业，并在地面对井下裂缝进行微地震监测；S3, nitrogen fracturing operation, that is, nitrogen fracturing operation is performed on the coal seam section of the operation well, and microseismic monitoring is performed on the underground fractures on the ground;
S4，二氧化碳气相压裂，完成S3步骤氮气压裂作业后，对煤层进行二氧化碳气相压裂，并在地面对井下裂缝进行微地震监测；S4, carbon dioxide gas phase fracturing, after completing the S3 step nitrogen gas fracturing operation, carbon dioxide gas phase fracturing is performed on the coal seam, and microseismic monitoring is performed on the underground fractures on the ground;
S5，数据汇总分析，完成S4步骤后，对S3、S4步骤获得的裂缝数量、宽度、深度及延伸方向数据进行分析，如果没有达到预期效果，则可重复S3、S4。S5, data summary analysis, after step S4 is completed, analyze the number, width, depth and extension direction data of cracks obtained in steps S3 and S4, if the expected effect is not achieved, repeat S3 and S4.
进一步的，所述的S1步骤中的待改造煤层气井为衰竭井、堵塞井、低产井中的任意一种。Further, the coalbed methane well to be reformed in the S1 step is any one of depleted wells, plugged wells, and low-yield wells.
进一步的，所述的S2步骤中，所述的设备和材料包括氮气泵车、高压二氧化碳爆破管、液态二氧化碳等。Further, in the step S2, the equipment and materials include a nitrogen pump truck, a high-pressure carbon dioxide explosion tube, liquid carbon dioxide, and the like.
进一步的，所述的S3步骤中，所述的氮气压裂作业中，所用压裂液为氮气，不再使用任何其他介质。Further, in the step S3, in the nitrogen fracturing operation, the fracturing fluid used is nitrogen, and no other medium is used.
进一步的，所述的S3步骤中，所述的氮气压裂作业中,氮气温度为煤层温度±3℃，氮气排量为200-400m3/min，氮气用量计算方法为：Further, in the step S3, in the nitrogen fracturing operation, the nitrogen temperature is ±3°C of the coal seam temperature, the nitrogen displacement is 200-400m 3 /min, and the nitrogen consumption is calculated as follows:
其中：Dt：氮气用量，单位m3；Among them: D t : nitrogen consumption, unit m 3 ;
H：煤厚，单位m；H: coal thickness, unit m;
R：压裂影响半径，单位m；R: fracturing influence radius, unit m;
进一步的，所述S3步骤中，微地震的监测基站平均分布在以井口为中心、半径150-250m的圆形上，微地震监测基站数量不少于8个，相邻两个监测基站直线间距不小于80m。Further, in the step S3, the microseismic monitoring base stations are evenly distributed on a circle with the wellhead as the center and a radius of 150-250m, the number of microseismic monitoring base stations is not less than 8, and the linear distance between two adjacent monitoring base stations Not less than 80m.
进一步的，所述S4步骤中，二氧化碳爆破压力为80-300MPa，液态二氧化碳用量计算方式为：Further, in the step S4, the explosion pressure of carbon dioxide is 80-300MPa, and the calculation method for the amount of liquid carbon dioxide is:
其中：in:
二氧化碳用量，单位kg； Carbon dioxide consumption, unit kg;
dg：高压爆破管内径，单位m，取值0.089m；d g : Inner diameter of the high-pressure blasting pipe, in m, with a value of 0.089m;
H：煤厚，单位m；H: coal thickness, unit m;
液态二氧化碳密度，单位kg/m3。 The density of liquid carbon dioxide, in kg/m 3 .
进一步的，所述S4步骤中，二氧化碳气相压裂时，二氧化碳温度为-5℃-5℃，且实施气相压裂时，时间为20-40毫秒，爆破后静置保压时间为10-60分钟。Further, in the S4 step, when the carbon dioxide gas phase fracturing is performed, the temperature of the carbon dioxide is -5°C-5°C, and when the gas phase fracturing is performed, the time is 20-40 milliseconds, and the standing pressure holding time after blasting is 10-60 minute.
进一步的，所述的S5步骤中，当重复进行S3步骤和S4步骤的压裂气相压裂时，相邻两次S3步骤和S4步骤的压裂气相压裂中，后一次的压裂气相压裂时使用的氮气和二氧化碳量为前一次的压裂气相压裂使用的氮气和二氧化碳量的0.5—2.5倍。Further, in the S5 step, when the fracturing gas phase fracturing of the S3 step and the S4 step is repeated, in the gas phase fracturing of the fracturing steps of the two adjacent steps S3 and S4, the gas phase fracturing of the latter fracturing The amount of nitrogen and carbon dioxide used in fracturing is 0.5-2.5 times the amount of nitrogen and carbon dioxide used in the previous fracturing gas phase fracturing.
本发明一方面施工便捷，施工作业自动化程度、施工控制精度高，能量转换率高，施工工艺通用性好，较传统压裂改造技术施工成本低，对煤层二次污染小。另一方面本发明在实施增产改造时，在可进行精确公式计算的同时，另可对压裂作业效果进行精确检测，提高了压裂作业中氮气和二氧化碳介质用量和使用的控制精度，从而有效克服了传统压裂改造技术控制精度差、资源浪费等现象，从而极大的提高煤层气低产井增产改造作业的工作效率和质量，并有效的降低了施工成本和施工作业风险。On the one hand, the invention has convenient construction, high automation degree of construction operation, high construction control precision, high energy conversion rate, good construction technology versatility, lower construction cost than traditional fracturing transformation technology, and less secondary pollution to coal seams. On the other hand, when the present invention implements production stimulation, it can not only perform accurate formula calculation, but also accurately detect the effect of fracturing operations, which improves the control accuracy of the amount and use of nitrogen and carbon dioxide media in fracturing operations, thereby effectively It overcomes the poor control accuracy and resource waste of traditional fracturing technology, thereby greatly improving the work efficiency and quality of stimulation operations in low-production coalbed methane wells, and effectively reducing construction costs and construction risks.
附图说明Description of drawings
图1为本发明方法流程示意图；Fig. 1 is a schematic flow sheet of the method of the present invention;
图2、图3、图4为同一煤层气低产井改造前和改造后煤层气日产量曲线示意图。Figure 2, Figure 3, and Figure 4 are schematic diagrams of the daily production curves of the same coalbed methane low production well before and after reconstruction.
具体实施方式Detailed ways
实施例1Example 1
结合某衰竭井为例，该井井口坐标：X＝200-4008116.77m Y＝38408278.37m H＝922.66m；预裂缝影响范围70m，煤层厚度为7.6m。Taking a depleted well as an example, the wellhead coordinates of this well are: X＝200-4008116.77m Y＝38408278.37m H＝922.66m; the pre-fracture influence range is 70m, and the coal seam thickness is 7.6m.
如图1和2所示，该煤层气低产井氮气-二氧化碳联合改造增产方法，包括以下步骤：As shown in Figures 1 and 2, the nitrogen-carbon dioxide combined stimulation method for low-production wells of coalbed methane includes the following steps:
S1，预制抽采井孔，根据待改造煤层气井地质构造条件和历史排采数据，对该井进行通洗井作业。S1, prefabricated drainage wellbore, according to the geological structure conditions and historical drainage data of the coalbed methane well to be reformed, carry out well flushing operation on the well.
S2，预制设备和材料，该井煤层厚度7.6m，井径0.124m，煤层温度为15℃，煤层顶板为砂岩，底板为砂质泥岩，准备氮气泵车、二氧化碳高压管、液态氮气、液态二氧化碳等；S2, prefabricated equipment and materials, the coal seam thickness of the well is 7.6m, the well diameter is 0.124m, the temperature of the coal seam is 15°C, the roof of the coal seam is sandstone, and the floor is sandy mudstone. Prepare nitrogen pump truck, carbon dioxide high-pressure pipe, liquid nitrogen, liquid carbon dioxide Wait;
S3，氮气压裂作业，对该井进行氮气压裂作业，氮气用量为58466m3，氮气排量为350m3/min，氮气排出温度为14-17℃，微地震监测基站布展方式是以井口为中心、半径为200m圆形上，微地震监测基站数量8个，相邻两个基站直线距离153m；S3, nitrogen fracturing operation, nitrogen fracturing operation is carried out on this well, the nitrogen consumption is 58466m 3 , the nitrogen discharge rate is 350m 3 /min, the nitrogen discharge temperature is 14-17°C, and the deployment method of the microseismic monitoring base station is based on the wellhead On a circle with a center and a radius of 200m, there are 8 microseismic monitoring base stations, and the straight-line distance between two adjacent base stations is 153m;
S4，二氧化碳气相压裂，利用二氧化碳高压管对煤层段进行爆破，二氧化碳爆破压力为120MPa，二氧化碳高压管内液态二氧化碳用量为47.5kg；S4, carbon dioxide gas phase fracturing, using carbon dioxide high-pressure pipe to blast the coal seam section, the carbon dioxide blasting pressure is 120MPa, and the amount of liquid carbon dioxide in the carbon dioxide high-pressure pipe is 47.5kg;
S5，数据汇总分析，完成S4步骤后，对S3、S4步骤获得的裂缝数量、宽度、深度及延伸方向数据分析，满足煤层气井增产抽采工艺要求，本增产施工结束，并拆除相关设备转而进行煤层气抽采作业。S5, data summary analysis, after completing step S4, analyze the data on the number, width, depth and extension direction of fractures obtained in steps S3 and S4, and meet the production and extraction process requirements of coalbed methane wells. Carry out coalbed methane extraction operations.
S3步骤中氮气用量计算公式为： The formula for calculating the amount of nitrogen used in step S3 is:
其中：Dt：氮气总量，单位m3；Among them: D t : total amount of nitrogen, unit m 3 ;
H：煤厚，单位m；H: coal thickness, unit m;
R：压裂影响半径，单位m，R＝70m；R: Fracturing influence radius, unit m, R=70m;
S4步骤中二氧化碳用量计算公式为： The formula for calculating the amount of carbon dioxide in the step S4 is:
其中：in:
二氧化碳用量，单位kg； Carbon dioxide consumption, unit kg;
dg：高压爆破管内径，单位m，取值0.089m；d g : Inner diameter of the high-pressure blasting pipe, in m, with a value of 0.089m;
H：煤厚，单位m；H: coal thickness, unit m;
液态二氧化碳密度，单位kg/m3； Liquid carbon dioxide density, unit kg/m 3 ;
实施例2Example 2
结合某堵塞井为例，该井井口坐标：X＝200-4009495.33 Y＝19677698.30 H＝927.10m；预裂缝影响范围75m；煤层厚度为6.5m。Taking a plugged well as an example, the wellhead coordinates of this well are: X＝200-4009495.33 Y＝19677698.30 H＝927.10m; the pre-fracture influence range is 75m; the coal seam thickness is 6.5m.
如图1和图3所示，该煤层气低产井氮气-二氧化碳联合改造增产方法，包括以下步骤：As shown in Figure 1 and Figure 3, the nitrogen-carbon dioxide combined stimulation method for low-production wells of coalbed methane includes the following steps:
S1，预制抽采井孔，根据待改造煤层气井地质构造条件和历史排采数据，对该井进行通洗井作业。S1, prefabricated drainage wellbore, according to the geological structure conditions and historical drainage data of the coalbed methane well to be reformed, carry out well flushing operation on the well.
S2，预制设备和材料，该井煤层厚度6.5m，井径0.124m，煤层温度为16℃，煤层顶板为砂岩，底板为泥岩。准备氮气泵车、二氧化碳高压管、液态氮气、液态二氧化碳等；S2, prefabricated equipment and materials, the thickness of the coal seam of this well is 6.5m, the well diameter is 0.124m, the temperature of the coal seam is 16°C, the roof of the coal seam is sandstone, and the floor is mudstone. Prepare nitrogen pump truck, carbon dioxide high-pressure pipe, liquid nitrogen, liquid carbon dioxide, etc.;
S3，氮气压裂作业，对该井进行氮气压裂作业，氮气用量为57403m3，氮气排量为400m3/min，氮气排出温度为15-18℃，微地震监测基站布展方式是以井口为中心、半径为250m圆形上，微地震监测基站数量10个，相邻两个基站直线距离154m；S3, nitrogen fracturing operation, nitrogen fracturing operation is carried out on this well, the nitrogen consumption is 57403m 3 , the nitrogen discharge rate is 400m 3 /min, the nitrogen discharge temperature is 15-18°C, and the deployment method of the microseismic monitoring base station is based on the wellhead On a circle with a center and a radius of 250m, there are 10 microseismic monitoring base stations, and the straight-line distance between two adjacent base stations is 154m;
S4，二氧化碳气相压裂，利用二氧化碳高压管对煤层段进行爆破，二氧化碳爆破压力为185MPa，二氧化碳高压管内液态二氧化碳用量为40.66kg；S4, carbon dioxide gas phase fracturing, using carbon dioxide high-pressure pipe to blast the coal seam section, the carbon dioxide blasting pressure is 185MPa, and the amount of liquid carbon dioxide in the carbon dioxide high-pressure pipe is 40.66kg;
S5，数据汇总分析，完成S4步骤后，对S3、S4步骤获得的裂缝数量、宽度、深度及延伸方向数据分析，满足煤层气井增产抽采工艺要求，本增产施工结束，并拆除相关设备转而进行煤层气抽采作业。S5, data summary analysis, after completing step S4, analyze the data on the number, width, depth and extension direction of fractures obtained in steps S3 and S4, and meet the production and extraction process requirements of coalbed methane wells. Carry out coalbed methane extraction operations.
S3步骤中氮气用量计算公式为： The formula for calculating the amount of nitrogen used in step S3 is:
其中：Dt：氮气总量，单位m3；Among them: D t : total amount of nitrogen, unit m 3 ;
H：煤厚，单位m；H: coal thickness, unit m;
R：压裂影响半径，单位m，R＝70m；R: Fracturing influence radius, unit m, R=70m;
S4步骤中二氧化碳用量计算公式为： The formula for calculating the amount of carbon dioxide in the step S4 is:
其中：in:
二氧化碳用量，单位kg； Carbon dioxide consumption, unit kg;
dg：高压爆破管内径，单位m，取值0.089m；d g : Inner diameter of the high-pressure blasting pipe, in m, with a value of 0.089m;
H：煤厚，单位m；H: coal thickness, unit m;
液态二氧化碳密度，单位kg/m3； Liquid carbon dioxide density, unit kg/m 3 ;
实施例3Example 3
结合某衰竭井为例，该井井口坐标：X＝200-4008524.40 Y＝19677479.17 H＝916.00m；预裂缝影响范围80m，煤层厚度为6.7m。Taking a depleted well as an example, the wellhead coordinates of this well are: X＝200-4008524.40 Y＝19677479.17 H＝916.00m; the pre-fracture influence range is 80m, and the coal seam thickness is 6.7m.
如图1和图4所示，该煤层气低产井氮气-二氧化碳联合改造增产方法，包括以下步骤：As shown in Figure 1 and Figure 4, the nitrogen-carbon dioxide combined stimulation method for low-production wells of coalbed methane includes the following steps:
S1，预制抽采井孔，根据待改造煤层气井地质构造条件和历史排采数据，对该井进行通洗井作业。S1, prefabricated drainage wellbore, according to the geological structure conditions and historical drainage data of the coalbed methane well to be reformed, carry out well flushing operation on the well.
S2，预制设备和材料，该井煤层厚度6.7m，井径0.124m，煤层温度为18℃，煤层顶板为砂质泥岩，底板为泥质砂岩。准备氮气泵车、二氧化碳高压管、液态氮气、液态二氧化碳等；S2, prefabricated equipment and materials, the coal seam thickness of the well is 6.7m, the well diameter is 0.124m, the temperature of the coal seam is 18°C, the roof of the coal seam is sandy mudstone, and the floor is argillaceous sandstone. Prepare nitrogen pump truck, carbon dioxide high-pressure pipe, liquid nitrogen, liquid carbon dioxide, etc.;
S3，氮气压裂作业，对该井进行氮气压裂作业，氮气用量为67321m3，氮气排量为300m3/min，氮气排出温度为17-20℃，微地震监测基站布展方式是以井口为中心、半径为250m圆形上，微地震监测基站数量8个，相邻两个基站直线距离191m；S3, nitrogen fracturing operation, nitrogen fracturing operation is carried out on this well, the nitrogen consumption is 67321m 3 , the nitrogen discharge rate is 300m 3 /min, the nitrogen discharge temperature is 17-20°C, and the deployment method of the microseismic monitoring base station is based on the wellhead On a circle with a center and a radius of 250m, there are 8 microseismic monitoring base stations, and the straight-line distance between two adjacent base stations is 191m;
S4，二氧化碳气相压裂，利用二氧化碳高压管对煤层段进行爆破，二氧化碳爆破压力为120MPa，二氧化碳高压管内液态二氧化碳用量为41.9kg；S4, carbon dioxide gas phase fracturing, using carbon dioxide high-pressure pipe to blast the coal seam section, the carbon dioxide blasting pressure is 120MPa, and the amount of liquid carbon dioxide in the carbon dioxide high-pressure pipe is 41.9kg;
S5，数据汇总分析，完成S4步骤后，对S3、S4步骤获得的裂缝数量、宽度、深度及延伸方向数据分析，满足煤层气井增产抽采工艺要求，本增产施工结束，并拆除相关设备转而进行煤层气抽采作业。S5, data summary analysis, after completing step S4, analyze the data on the number, width, depth and extension direction of fractures obtained in steps S3 and S4, and meet the production and extraction process requirements of coalbed methane wells. Carry out coalbed methane extraction operations.
S3步骤中氮气用量计算公式为： The formula for calculating the amount of nitrogen used in step S3 is:
其中：Dt：氮气总量，单位m3；Among them: D t : total amount of nitrogen, unit m 3 ;
H：煤厚，单位m；H: coal thickness, unit m;
R：压裂影响半径，单位m，R＝70m；R: Fracturing influence radius, unit m, R=70m;
S4步骤中二氧化碳用量计算公式为： The formula for calculating the amount of carbon dioxide in the step S4 is:
其中：in:
二氧化碳用量，单位kg； Carbon dioxide consumption, unit kg;
dg：高压爆破管内径，单位m，取值0.089m；d g : Inner diameter of the high-pressure blasting pipe, in m, with a value of 0.089m;
H：煤厚，单位m；H: coal thickness, unit m;
液态二氧化碳密度，单位kg/m3； Liquid carbon dioxide density, unit kg/m 3 ;
本发明一方面施工便捷，施工作业自动化程度、施工控制精度高，能量转换率高，施工工艺通用性好，另一方面本发明在实施增产改造时，在可进行精确公式计算的同时，另可对压裂作业效果进行精确检测，提高了压裂作业中氮气和二氧化碳介质用量和使用压力的控制精度，从而极大的提高煤层气低产井增产改造作业的工作效率和质量，并有效的降低了施工成本和施工难度。On the one hand, the present invention is convenient in construction, with high degree of automation in construction work, high construction control precision, high energy conversion rate, and good versatility in construction technology. Accurate detection of the effect of fracturing operations improves the control accuracy of the amount of nitrogen and carbon dioxide media and the pressure used in fracturing operations, thereby greatly improving the work efficiency and quality of stimulation operations for low-production coalbed methane wells, and effectively reducing the Construction cost and construction difficulty.
以上显示和描述了本发明的基本原理和主要特征和本发明的优点。本行业的技术人员应该了解，本发明不受上述实施例的限制，上述实施例和说明书中描述的只是说明本发明的原理，在不脱离本发明精神和范围的前提下，本发明还会有各种变化和改进，这些变化和改进都落入要求保护的本发明范围内。本发明要求保护范围由所附的权利要求书及其等效物界定。The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. What are described in the above-mentioned embodiments and the description only illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have Variations and improvements are possible, which fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112377166A (en) * | 2020-12-14 | 2021-02-19 | 西南石油大学 | Shale oil reservoir nitrogen-assisted carbon dioxide fracturing and development integrated method |
Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102287176A (en) * | 2011-05-09 | 2011-12-21 | 河南理工大学 | Coal bed pressing crack liquid system |
| EP2527586A1 (en) * | 2011-05-27 | 2012-11-28 | Shell Internationale Research Maatschappij B.V. | Method for induced fracturing in a subsurface formation |
| US20140124208A1 (en) * | 2006-03-03 | 2014-05-08 | Gasfrac Energy Services Inc. | Liquified petroleum gas fracturing system |
| CN104481462A (en) * | 2014-11-18 | 2015-04-01 | 山西潞安环保能源开发股份有限公司 | Coal-bed gas aging well production capacity increasing method |
| CN105332684A (en) * | 2015-11-13 | 2016-02-17 | 重庆大学 | A Coalbed Methane Displacement Drainage Technology Combined with High Pressure Water Explosion and CO2 Fracturing |
| CN106285768A (en) * | 2016-08-04 | 2017-01-04 | 重庆大学 | CO2 Directional Blast Initiation and Hydraulic Fracturing Coupling Enhanced Gas Drainage Method |
| CN106481328A (en) * | 2016-09-23 | 2017-03-08 | 太原理工大学 | A kind of utilization graininess dry ice builds the hot dry rock method that manually heat is stored up |
| US20170152433A1 (en) * | 2014-05-09 | 2017-06-01 | Halliburton Energy Services, Inc. | Cationic Polymers for Foam Fracturing Applications |
| CN107842351A (en) * | 2016-09-20 | 2018-03-27 | 中国石油大学(北京) | A kind of anhydrous energization composite fracturing method of liquefied petroleum air carbon dioxide |
| CN107905832A (en) * | 2017-11-06 | 2018-04-13 | 北京九尊能源技术股份有限公司 | The outburst elimination method of pump drainage is combined on a kind of nitrogen pressure break and ground with underground |
| CN108729897A (en) * | 2018-05-22 | 2018-11-02 | 中国石油大学(北京) | A kind of carbon dioxide-slippery water batch-mixed fracturing design method |
| CN109113701A (en) * | 2017-06-24 | 2019-01-01 | 高九华 | Using air as the anti-reflection technology of pulsating pressure-air creep pressure break and device of medium |
| CN109630085A (en) * | 2019-01-15 | 2019-04-16 | 中北大学 | A method for deep hole high-energy pulse fracturing step by step in coal seam |
| CN109736767A (en) * | 2019-01-18 | 2019-05-10 | 大庆中联信实石油科技开发有限公司 | A kind of supercritical carbon dioxide fracturing yield increasing technique |
| CN109751029A (en) * | 2017-11-01 | 2019-05-14 | 中国石油化工股份有限公司 | A kind of method of deep layer shale gas pressure break |
| CN209043750U (en) * | 2018-05-29 | 2019-06-28 | 西安科技大学 | A kind of coal and rock fracturing, anatonosis, desorption coupling experiment device |
-
2019
- 2019-07-15 CN CN201910634771.9A patent/CN110424937A/en active Pending
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140124208A1 (en) * | 2006-03-03 | 2014-05-08 | Gasfrac Energy Services Inc. | Liquified petroleum gas fracturing system |
| CN102287176A (en) * | 2011-05-09 | 2011-12-21 | 河南理工大学 | Coal bed pressing crack liquid system |
| EP2527586A1 (en) * | 2011-05-27 | 2012-11-28 | Shell Internationale Research Maatschappij B.V. | Method for induced fracturing in a subsurface formation |
| US20170152433A1 (en) * | 2014-05-09 | 2017-06-01 | Halliburton Energy Services, Inc. | Cationic Polymers for Foam Fracturing Applications |
| CN104481462A (en) * | 2014-11-18 | 2015-04-01 | 山西潞安环保能源开发股份有限公司 | Coal-bed gas aging well production capacity increasing method |
| CN105332684A (en) * | 2015-11-13 | 2016-02-17 | 重庆大学 | A Coalbed Methane Displacement Drainage Technology Combined with High Pressure Water Explosion and CO2 Fracturing |
| CN106285768A (en) * | 2016-08-04 | 2017-01-04 | 重庆大学 | CO2 Directional Blast Initiation and Hydraulic Fracturing Coupling Enhanced Gas Drainage Method |
| CN107842351A (en) * | 2016-09-20 | 2018-03-27 | 中国石油大学(北京) | A kind of anhydrous energization composite fracturing method of liquefied petroleum air carbon dioxide |
| CN106481328A (en) * | 2016-09-23 | 2017-03-08 | 太原理工大学 | A kind of utilization graininess dry ice builds the hot dry rock method that manually heat is stored up |
| CN109113701A (en) * | 2017-06-24 | 2019-01-01 | 高九华 | Using air as the anti-reflection technology of pulsating pressure-air creep pressure break and device of medium |
| CN109751029A (en) * | 2017-11-01 | 2019-05-14 | 中国石油化工股份有限公司 | A kind of method of deep layer shale gas pressure break |
| CN107905832A (en) * | 2017-11-06 | 2018-04-13 | 北京九尊能源技术股份有限公司 | The outburst elimination method of pump drainage is combined on a kind of nitrogen pressure break and ground with underground |
| CN108729897A (en) * | 2018-05-22 | 2018-11-02 | 中国石油大学(北京) | A kind of carbon dioxide-slippery water batch-mixed fracturing design method |
| CN209043750U (en) * | 2018-05-29 | 2019-06-28 | 西安科技大学 | A kind of coal and rock fracturing, anatonosis, desorption coupling experiment device |
| CN109630085A (en) * | 2019-01-15 | 2019-04-16 | 中北大学 | A method for deep hole high-energy pulse fracturing step by step in coal seam |
| CN109736767A (en) * | 2019-01-18 | 2019-05-10 | 大庆中联信实石油科技开发有限公司 | A kind of supercritical carbon dioxide fracturing yield increasing technique |
Non-Patent Citations (3)
| Title |
|---|
| 凌云 等: "CO2复合压力技术在鄂尔多斯盆地东部的应用", 《IFDC》 * |
| 孙鑫 等: "二氧化碳压裂技术研究综述", 《油田化学》 * |
| 巩跃斌 等: "高瓦斯矿井长钻孔CO2气相压裂增透试验研究", 《试验研究》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112377166A (en) * | 2020-12-14 | 2021-02-19 | 西南石油大学 | Shale oil reservoir nitrogen-assisted carbon dioxide fracturing and development integrated method |
| CN112377166B (en) * | 2020-12-14 | 2021-11-09 | 西南石油大学 | Shale oil reservoir nitrogen-assisted carbon dioxide fracturing and development integrated method |
| US11371328B1 (en) | 2020-12-14 | 2022-06-28 | Southwest Petroleum University | Integrated method for nitrogen-assisted carbon dioxide fracturing and development of shale oil reservoirs |
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