Research on the Crucial Pathway of Efficient Development of Coalbed Methane in CNOO

Abstract:As our country’s energy consumption continues to rise, energy security is facing new challenges, and it is urgent to accelerate the progress of unconventional oil and gas exploration and development. As an important unconventional oil and gas resource, coalbed methane has great potential in our country and is an important part of national energy security, energy structure optimization and energy transformation. Focusing on the needs of the new situation of energy security and the overall deployment of coalbed methane development under the “dual carbon” goal, this paper uses practical methods to systematically sort out the efficient exploration and development process of CNOOC in recent years, and explores the efficient development mode of three-dimensional, complementary and all-round gas reservoir development such as medium and shallow layers, thin coal seams, and deep coal seams. The materialist dialectical analysis of CNOOC coalbed methane resources is used to analyze the problems and challenges of resources, policies, technologies, and management in the exploration and development of CNOOC coalbed methane resources. Finally, the main contradictions in the practice of efficient development of CNOOC coalbed methane are summarized, and the key path to further promote the efficient development of CNOOC coalbed methane is formed, and the construction of CNOOC coalbed methane production capacity and onshore trillions of atmospheres is accelerated to help ensure national energy security.
Key words: energy security; dual carbon goals; coalbed methane; efficient development; Critical path

0 Introduction

As the world’s largest energy producer and consumer, China’s energy production has maintained steady growth in recent years, with an energy self-sufficiency rate of more than 80% in 2022. However, as geopolitical conflicts become more frequent, China’s energy imports face greater uncertainty. In 2022, China’s dependence on petroleum and natural gas will be 71.3% and 41.8% respectively, and it is expected that by 2025, the dependence on natural gas will be 45%, and by increasing the development of unconventional oil and gas, the dependence will decrease by an average of 1.2% per year in the past three years.
“Carbon peaking and carbon neutrality” is a major national strategy personally planned, deployed, and promoted by General Secretary Xi Jinping to solve the outstanding problems of resource and environmental constraints and realize the sustainable development of the Chinese nation, and it is also a solemn commitment to build a community with a shared future for mankind. According to the decision-making and deployment of the Party Central Committee on “carbon peaking and carbon neutrality”, the State Council issued the “Notice of the State Council on Printing and Distributing the Action Plan for Carbon Peaking before 2030” on October 24, 2021, which proposes to accelerate the large-scale development of unconventional oil and gas resources such as shale gas, coalbed methane, and tight oil (gas). By 2030, economic and social development will undergo a comprehensive green transformation, and the energy utilization efficiency of key energy-consuming industries will reach the international advanced level. By 2060, the proportion of non-fossil energy consumption will reach more than 80%, and the goal of carbon neutrality will be successfully achieved.
China has abundant coalbed methane resources, and the efficient development of coalbed methane is of great significance to reducing coal mine gas explosion accidents, expanding natural gas supply, reducing environmental pollution, and promoting the realization of the “dual carbon” goal. The development goal of the “14th Five-Year Plan” coal plan “Coalbed Methane (Coal Mine Gas) Development and Utilization Plan” issued by the National Energy Administration in March 2022 is: during the “14th Five-Year Plan” period, 2500×10 m³ of proven geological reserves of coalbed methane will be added, and the development and utilization of CNOOC coalbed methane will be 100×10⁸m³2-3 in 2025. Therefore, it is urgent to explore a key path for breakthroughs in the efficient development of coalbed methane.
Zoomlion Co., Ltd. (hereinafter referred to as “Zoomlion”), as the main force in China’s coalbed methane exploration and development and the pioneer of the national coalbed methane industry demonstration base, uses CNOOC’s advanced offshore oil and gas development technology and international management experience to integrate the new energy security strategy of “four revolutions and one cooperation” into it, emphasizes the company’s active actions in implementing the national energy strategy, and is committed to building a strong coalbed methane industry.
The core task of ensuring the supply of oil and gas resources is to increase reserves and production. This is of great significance to ensure national energy security. After nearly 10 years of rapid and efficient development, Zoomlion’s coalbed methane production has increased from 8.13×10⁸m³ in 2014 to 42.7×108m³ in 2022, an increase of 4.25 times.

1 Analysis of the contradictions in the efficient development of coalbed methane

1.1 Development status of coalbed methane industry

1.1.1 Foreign development status
The world’s coalbed methane resources are about 268×10¹²m³, and the main producing countries are the United States, Canada, Australia and China4. The United States is the birthplace of coalbed methane technology, which has been commercially developed on a commercial scale in the San Juan Basin, the Black Warrior Basin, and the Powder River Basin, with a peak of 556.71×10⁸m³ in 2008, and with the rise of the shale gas industry, the investment and workload of coalbed methane have decreased, and the current annual output is 200×10⁸m³. Canada and Australia have successfully realized the commercial development of coalbed methane based on the theoretical system of the United States by improving and developing coiled tubing construction and nitrogen foam fracturing technologies, and Canada’s coalbed methane production peaked at 95×10⁸m³ in 2009, and the current annual output is about 85×108m³. Australia learned from the experience of the United States and explored the multi-layer co-mining technology of coal seam and tight sandstone gas. By 2018, Australia’s coalbed methane production was about 393×10⁸m³, which is currently above 400×10m³5.
1.1.2 Domestic development status
In 1996, with the approval of the State Council, Zoomlion Coalbed Methane Co., Ltd. was established, and it enjoyed the exclusive right to cooperate with foreign countries in the exploration, development, and production of coalbed methane. At present, China has formed two major coalbed methane industry bases in the eastern margin of the Ordos Basin and the Qinshui Basin, and has developed a number of coalbed methane fields represented by Panzhuang and Fanzhuang.5 In 2022, the national coalbed methane production was 115.7×10⁸m³, a year-on-year increase of 9.9%. Overall, China has made significant progress in the theory and technology of coalbed methane exploration and development in the past 40 years, but there is still a big gap with the national energy planning goals due to factors such as complex resource endowment conditions and poor adaptability of key technologies in some development projects (3).
1.1.3 Development status of CNOOC coalbed methane
The mining rights of Zoomlion Company cover an area of 16,154 square kilometers and are distributed in 6 provinces and regions. In 2011, CNOOC held 50% of Zoomlion, in 2014, CNOOC held 100%, and in 2019, it became a wholly-owned subsidiary of CNOOC, with the basic strength and engineering technology research and gradually increased investment, in the past five years, the cumulative amount of more than 200×108 yuan, the comprehensive growth rate of 42.3%, in recent years, Zoomlion has successively overcome technical problems such as thin coal seam and deep coalbed methane development. In the Ordos Basin, the three-dimensional development of medium and shallow coalbed methane, deep coalbed methane and tight gas has been realized⁶. In October 2020, the average daily gas production jumped to the first place among coalbed methane enterprises. In 2019~2022, the annual gas production increased from 19.11×10⁸m³ to 42.7×108m³, with an average annual growth rate of 41%; The daily gas production increased from 340×10⁴m³ at the beginning of 2019 to 1200×10⁴m³ in 2021, quadrupling the daily production in three years.

1.2 The contradiction between the abundance of overall reserves and the lack of high-quality resources

1.2.1 Abundant resources
China’s coalbed methane geological resources rank among the top three in the world, with 42 major coalbed basins with 30.05×10¹²m³ buried at a depth of less than 2000m, 40×10¹²m³ with a buried depth of more than 2000m, and 4×10¹²m³ of coalbed methane geological resources with real exploitable value.
1.2.2 Low degree of exploration
The problems in the process of industrial development are gradually exposed. In the upstream aspect, due to resource and technical constraints, it is difficult to continue to increase production in the later stage. In terms of industrial support, the industry-related systems and mechanisms are not perfect, and industrial management is still in the stage of exploration and exploration. As of the end of 2022, the resource proven rate of coalbed methane in the country was only 2.58%, which is mainly manifested as follows: First, most of the coalbed methane producing areas are in the early stage of development, and only Qinshui and Ordos basins have basically achieved large-scale development among the nine large coal-gathering basins in the country; second, medium and low-rank coal accounts for 69%, which has not yet been utilized on a large scale; Third, the development of deep coal seam resources faces technical and economic challenges. The coalbed methane resources at a depth of 1500~2000m are about 9.47×10⁸m³, accounting for 31.51% of the total resources. Coalbed methane resources with a depth of more than 2000m are the main and key part of our country’s future coalbed methane industry strategy, but to make full use of this part of the resources, we are currently facing a series of technical problems and lack of relevant supporting policy support5.

1.3 Contradiction between complex development conditions and high technical requirements

1.3.1 Efficient development is challenging
First, the geological conditions of China’s coal seams are complex8-10]. A series of characteristics such as the diversity of coal-forming conditions, coal metamorphism, hydrodynamics, and the diversity of tectonic movements make the accumulation conditions of coalbed methane complex and the types of gas reservoirs highly different. Second, the adaptability of unconventional technology is weak. The development of coalbed methane involves nearly 100 specific technologies in 7 major specialties, and due to the large differences in geological conditions in each block, mature technologies are not universal. Third, the research on low-rank coalbed methane is insufficient. Exploration and development are mainly concentrated in the middle and high-rank coal distribution areas, and the research on low-rank coal areas is generally insufficient. Fourth, the exploration and development of deep coalbed methane is in its infancy, and the differences in the physical properties of coal reservoirs are even more special. At present, there is a lack of in-depth systematic understanding of the sedimentation, diagenesis, and reservoir characteristics of deep coal reservoirs, the in-situ occurrence state is complex, the occurrence characteristics are unclear, and the resource evaluation system is not perfect.
1.3.2 High investment risk
Coalbed methane development has the characteristics of large deployment scale, large investment and poor economic performance. According to statistics on China’s investment in coalbed methane exploration over the years, the intensity of exploration investment reached its peak at 63,600 yuan/square kilometer in 2012, and has been on a downward trend since then. Up to now, the total investment in exploration and development has reached more than 1000×108 yuan, the production scale of coalbed methane in Qinshui and eastern Hubei is 142×108 m³, the production capacity is in place 58%, the initial discharge and production cycle of coalbed methane is long, and the management and supporting mechanisms are also the main factors [5]. Although China introduced many preferential policies to encourage the development and utilization of coalbed methane in the early stage of the development of the coalbed methane industry, the coalbed methane industry is still developing slowly due to large investment and slow return on investment.
1.3.3 Management innovation is urgently needed
Low cost is the core competitiveness of oil companies, and it is also the key to improving profitability and combating the risk of oil price fluctuations. Coalbed methane has always been developed in a low-cost mode and low-cost mode as one of CNOOC’s most competitive strategies, with the long-term goal of reducing costs and increasing efficiency, promoting technology improvement and management optimization, and stimulating grassroots management innovation. At the same time, the safety situation is becoming more and more severe, the control standards are getting higher and higher, and the management requirements are more refined.

1.4 Outstanding contradictions in CNOOC’s development of coalbed methane business

In July 2023, Zoomlion was invited to participate in the seminar on the development of unconventional natural gas industry held by the Shanxi Provincial Development and Reform Commission. The meeting focused on the government-enterprise coordination to promote the high-quality development of the industry, involving the continuation of mining rights, land use, forestry and grass, and scientific and technological innovation in coalbed methane exploration and development, and pointed out the outstanding contradictions currently facing the coalbed methane industry.
1.4.1 The dual pressure of efficient development and land policy
The national energy department has delegated the registration authority of coalbed methane mining rights to provincial departments, and fully implemented the system of competitive transfer and exploration and production. Taking Shanxi Province as an example, in 2020, the first local regulation for coalbed methane, “Administrative Measures for Coalbed Methane Exploration and Mining in Shanxi Province”, stipulates that the first registration of prospecting rights is valid for 5 years and can be renewed twice, each time for 5 years. The coalbed methane exploration right holder shall complete the minimum exploration investment of 10×10⁴ per square kilometer per year from the date of the first registration of the exploration block in accordance with relevant regulations. In addition, with the increasing implementation of national policies on environmental protection and ecological environment year by year, the management authority of national ministries and commissions has gradually been delegated to local governments, and exploration and development work needs to be deployed in advance, involving many preconditions such as forest land procedures, environmental impact assessment, cultural relics survey, energy conservation assessment, soil and water conservation, and reclamation plans.
1.4.2 Multiple problems in exploration, development and reserve management
Since Zoomlion merged into CNOOC in 2019, it has successively formulated and revised a series of management systems, but there are still problems in exploration, reserve management, and development that are not suitable for the actual exploration and development of coalbed methane. In terms of exploration, unconventional natural gas requires multi-point capacity evaluation and trial production, especially the long time of coalbed methane discharge and the lack of supporting facilities such as pipelines, resulting in some waste of resources. In terms of reserve management, to achieve reserve probing, a large number of exploration wells need to be invested, resulting in large exploration investment and may affect the deployment of subsequent development projects. In terms of development, the existing management system is based on proven reserves, but due to the complexity and uncertainty of unconventional natural gas geological conditions, it is decided that exploration and development must be integrated, and the reserves and production capacity scale can be finally determined after the implementation of the integration plan [12]. However, the preparation of EIA needs to be based on a deterministic plan, and the preparation and approval time of EIA is long, which seriously affects the progress of capacity construction.
1.4.3 Technical difficulties and bottlenecks faced
The technical level restricts industrial development. First, the evaluation technology of coalbed methane geological engineering is imperfect, and the evaluation and optimization of coalbed methane enrichment areas and the prediction of coalbed methane development potential are limited, which restricts the development efficiency of coalbed methane. Second, the imperfect technology of coalbed methane well drainage and gas production based on pulverized coal control makes the problem of pulverized coal clogging in the wellbore frequently occurring 1³ in the actual development process. Third, with the gradual transition from shallow to deep and from simple tectonic areas to complex tectonic areas in the exploration and development of coalbed methane, technical bottlenecks such as understanding the law of coalbed methane enrichment under complex geological conditions, evaluating the physical properties of reservoirs, and developing deep coalbed methane have become increasingly prominent.

2 Practice, understanding, and re-practice

2.1 Consolidate the resource base from shallow to deep

At present, it has moved from the stable development of medium and shallow coal seams to the efficient development of marginal resources such as thin coal seams, explored the establishment of a supporting technical system for deep coalbed methane, and has made efforts to advance into new resource fields such as tight oil and gas.

2.1.1 Demonstration and promotion area for efficient exploration and development of medium and shallow coal seams
Zoomlion has accumulated rich experience in the field of coalbed methane development, especially in the successful development practice of medium and shallow coal seams such as Panhe and Shizhuang South, and has iteratively improved the engineering supporting technologies suitable for different geological conditions and the existing comprehensive treatment technologies for inefficient wells, which has provided an important reference for the development of shallow and medium coalbed methane14. At the same time, a set of economical, effective and generalizable diversified drilling and completion technology systems suitable for shallow and medium coalbed methane has been formed, which has promoted the economic production of medium and shallow coalbed methane.
2.1.2 Pilot demonstration area for comprehensive development of thin coal seams
Thin coal seams refer to coal seams with a thickness of less than 1.3 m underground, and these coal seams have large differences in gas content and relatively poor resource abundance, and have long been regarded as forbidden areas for coalbed methane development5. Zoomlion’s P block is China’s first commercially operated coalbed methane demonstration project, which is rich in coal resources, of which thin coal seams account for a large proportion. Despite many difficulties, Zoomlion has made a double breakthrough in the development technology and production of thin coalbed methane in Block P through differentiated technical research and continuous innovation of multiple and thin coal seams, as shown in Figure 1. At present, a total of 212 wells have been built, and the highest daily production of a single well has reached more than 1.1×10⁴m³, which verifies the efficient development mode and effect of thin coalbed methane15.

Fig. 1 Daily production of coalbed methane in block P

2.1.3 Breakthrough area for efficient development of deep coal seams
Deep coalbed methane is the key to increasing oil and gas reserves and production in CNOOC’s unconventional sector, with a resource of 30×10¹²m³, accounting for one-third of coalbed methane resources5. At present, due to technical and geological constraints in China, the development and utilization of deep coalbed methane is still facing many challenges, Zoomlion has conducted in-depth research on the geological conditions and development process of deep coalbed methane, continuously optimized drilling, fracturing and other technical solutions, improved mining efficiency and economy, and aims to build a deep coal seam exploration and development demonstration area. In 2023, Zoomlion discovered China’s first 100 billion cubic meter deep coalbed methane field Yishenfu deep coalbed gas field 16 on the eastern margin of the Ordos Basin. The major breakthrough in the exploration and development of coal seams in the deep eastern margin of the Ordos Basin has important guiding significance for the exploration of resources in similar basins and the increase of unconventional oil and gas reserves and production in China.17

2.2 Break through the main technology and enhance technical capabilities

2.2.1 Improve accumulation research and innovate exploration concepts
Zoomlion has made progress in the study of the accumulation mechanism of deep coalbed methane, and innovatively put forward the “complementary” and “three-dimensional” exploration concepts of tight gas and coalbed methane. The application of this concept makes the exploration of deep coal seams more efficient, and at the same time reduces operating costs, reducing costs and increasing efficiency in deep coal seam development [5.18].
The concept of “complementary” exploration refers to the complementary development of two different types of natural gas resources, tight gas and coalbed methane, in the process of exploration to maximize the utilization of resources.
The “three-dimensional” exploration concept refers to the comprehensive exploration of coalbed methane and sandstone gas resources from multiple angles and layers of vertically distributed reservoir combinations during exploration, so as to achieve all-round reservoir transformation and drainage and production process research, as shown in Figs. 2 and 3.

Fig. 2 Schematic diagram of three-dimensional exploration

Single combined wells

Fig.3 Comparison of combined production wells and single production wells

2.2.2 Technological innovation and practice the “new excellent speed” of land drilling and completion
Based on the practical experience of drilling and completion, Zoomlion has carefully studied the adaptability of coalbed methane drilling well types and drilling and completion processes, carried out research on the optimization design of horizontal wells, and formed the drilling and completion technology of coal-based formations: First, optimize the wellbore structure of horizontal wells, strengthen the wellbore stability technology of complex formations, optimize the wellbore structure of horizontal wells from three to two, ensure the success rate of completion casing, and solve the problem of gradually increasing the depth of coalbed methane development5.19; The second is to improve reservoir protection and drilling rate [20]. The horizontal section uses polymer mud system and near-drill bit guidance technology to reduce reservoir pollution, increase the drilling encounter rate, and shorten the drilling time of the horizontal section. The third is to improve the integrity of the wellbore, and after completion, the bridge plug is lowered, the pressure is tested, and the integrity of the wellbore is improved21].
2.2.3 Deepen the understanding of complex fracture systems in coal reservoirs and innovate large-scale reservoir transformation technologies
In terms of overcoming the technical problems of fracturing deep coalbed methane horizontal wells, Zoomlion has learned from the fracturing technology of medium and shallow coal seams and the formation mechanism of complex fractures in coal seams, innovated fracturing ideas, and optimized the combination of fracturing liquid system and proppant to form a large-scale and effective renovation technology for reservoirs. First, the “ultimate volume fracturing” technology, with the deepening of geological engineering understanding and the clarification of the main controlling factors affecting the transformation effect, it is necessary to realize the development of scale benefits of deep coalbed methane, achieve breakthroughs in fracturing concepts and technologies, and form “ultra-large, ultra-dense, fracture network, and full support” “ultimate volume fracturing” technology. The second is the low-cost multi-cluster transformation technology of horizontal wells22, under the condition of fixed section length, the increase in the number of clusters has more advantages, the fracture height is controlled, the effective fracture propagation range is increased, and the increase of fracture conductivity at the same sand addition scale is more conducive to promoting the desorption degree of coalbed methane in deep ultra-low permeability reservoirs, and effectively promoting the release of production capacity, as shown in Figs. 4 and 5.

Fig.4 Schematic diagram of large-scale fracturing of horizontal wells

Fig.5 Single well production of deep coal seam in block XX

2.3 Deepen the reform of the system and mechanism and improve the level of management

2.3.1 Strengthen the deep integration of geological engineering and the integration of double desserts
In the “double sweet spot” area of geology and engineering [23], the deployment of multiple wells in the same well site can efficiently carry out drilling, completion, renovation and construction and obtain high yields, which is conducive to the efficient exploration and development of complex oil and gas reservoirs and the formation of effective technical management models and methods. Due to the unconventional, diversity and heterogeneity of coalbed methane resources, it is needed
overcoming many challenges in understanding, developing, and transforming coalbed methane reservoirs; The second is to shorten the project construction period, achieve high yield with fewer wells, and effectively improve work efficiency by using information technology to strengthen the tracking of drilling while drilling, real-time collection of fracturing construction parameters, and timely sharing and interaction. The third is to enhance cooperation and efficiency. In the past two years, a total of 9 high-efficiency wells have been built in the two coalbed methane fields of Shenfu and Jinxi, with a total unobstructed flow rate of 1080×10⁴m³/d.
2.3.2 Deeply practice the concept of “new excellent and fast” of CNOOC land
“New Youkuai” is an innovative project carried out by CNOOC for major tasks to increase reserves and production24], which improves the development efficiency and economic benefits of oil and gas fields through technological innovation and management mechanism innovation, and provides experience and reference for the sustainable development of oil and gas fields in the future. In 2023, it is expected to complete 1,072 drilling wells, complete 1,013 wells, and build 10 “new excellent and fast” benchmark wells throughout the year, significantly improving speed and efficiency, saving nearly 600 days and speeding up nearly 30% compared with the design period.
2.3.3 Strengthen the integrated management and coordination mechanism
As a pioneer in the land clean energy sector, Zoomlion has continuously optimized the system and mechanism, improved the contractor management system according to the characteristics of “small Party A and large Party B”, created a contractor management model, strengthened the interconnection and interaction between Party A and Party B, and increased the control of the construction process of many projects, helping to speed up and improve efficiency. Strengthen the integration of geological engineering and production coordination, establish a “three-level” linkage and coordination mechanism through meetings, networks, joint offices, etc., coordinate resources, share information in a timely manner, and jointly promote organization and management.
2.3.4 Optimize the government-enterprise collaborative project management process
In order to cope with the challenges of land use contradictions, Zoomlion has optimized the project management process and improved work efficiency by simplifying approval procedures and strengthening internal collaboration. Before the implementation of the project, Zoomlion will take the initiative to communicate with the local government to understand local policies, regulations and regulations in advance to ensure that the project meets local requirements and standards. At the same time, sufficient research and evaluation should be carried out, detailed plans should be formulated to ensure that all work in the project implementation process can be carried out smoothly, and the efficiency of land use approval has increased by 60% compared with 2018 under the promotion of the reform of “decentralization, management and service”.

2.4 Continuous innovation and optimization of development models

2.4.1 Party building leads and promotes the deep integration of party building production
Under the guidance of party building, Zoomlion has realized the deep integration of party building work and production and operation by adhering to the guidance of party building, strengthening organizational construction, promoting system construction, and strengthening assessment and evaluation, and led high-quality development with high-quality party building.
The first is to strengthen organizational construction and consolidate the grassroots foundation. Strengthen the construction of grassroots party organizations, and set up joint party branches of Party A and Party B, select and strengthen grassroots party organizations, set up a “vanguard” to actively promote the leading role of party building to solve production problems, give full play to the role of party organizations as a fighting fortress and the vanguard and exemplary role of party members, and provide a strong organizational guarantee for the development of enterprises. The second is to strengthen assessment and evaluation and implement responsibility. Incorporate party building work into the overall performance appraisal system of enterprises, clarify assessment standards and weights, and promote and coordinate the development of party building work and production and operation.
2.4.2 Digitalization as a medium to promote the efficient development and construction of digital and intelligent gas fields
Zoomlion’s unconventional intelligent gas field construction is guided by CNOOC’s “14th Five-Year Plan” informatization plan, combined with the requirements of CNOOC’s top-level design of digital transformation, and formulates an implementation plan for intelligent gas fields that meet the characteristics of Zoomlion.
The first is to establish an integrated digital management system for gas reservoirs, wellbores, pipeline networks, gas collection and sales. Real-time monitoring of the operation status of underground equipment, wellhead equipment, and production process equipment, timely improvement of production measures, and improvement of production time; Analyze the adjustment suggestions of each well platform and production system to achieve balanced mining and maximize oil recovery. The second is to establish an integrated support system for exploration and development. This system will grasp the pre-drilling preparation of each well and the preparation of the drillable position of the well platform in real time, adjust the allocation of drilling rigs in a timely manner, and improve the timeliness of pre-drilling operations; Establish real-time information transmission while drilling to provide decision-making basis for timely adjustment of drilling personnel; Based on regional production laws and geological understanding, the sweet spot model of reserves in each region is established in a timely manner through the results of drilling data, which serves to adjust the drilling operation procedure while drilling.
2.4.3 Adhere to the mode of independent development and win-win cooperation
Zoomlion adheres to the development strategy of independent development and win-win cooperation, pays attention to improving its core competitiveness, and actively seeks cooperation and exchanges with all parties, comprehends advanced experience, and builds a learning enterprise and a learning organization.
Recently, Zoomlion and Huaxin Gas Group officially signed a strategic cooperation framework agreement, which is a tangible embodiment of Zoomlion’s independent development and win-win cooperation. In the later stage, we will further explore the exploration and development cooperation model, strengthen the technical exchange of coalbed methane exploration and development, accelerate the construction of pipeline network facilities, and effectively ensure the safe and stable supply of gas.
2.4.4 Focusing on the “dual carbon” goal, systematically promote the construction of “ecological well sites”
Zoomlion focuses on high efficiency, energy conservation, low carbon and environmental protection, and is committed to providing clean and efficient coalbed methane development and utilization solutions. Reduce production costs and energy consumption by optimizing production processes and strengthening management. In the Linxing block, Zoomlion Company formulated a special plan, clarified the node requirements, and established a harmless purification treatment station for tight gas production water on the basis of a number of studies such as “Produced Water Harmless Evaporation Treatment Experiment”. Zoomlion has formulated the “Work Plan for the Construction of Coalbed Methane “Ecological Wells” to promote the construction of “ecological wells” and solve problems such as mining and drainage disposal, greening, and centralized disposal of abandoned wells and wastes in coalbed methane wells.

3 Conclusions and suggestions

In the context of the new situation of energy security and the dual carbon goals, the coalbed methane industry has ushered in new development opportunities. China is rich in coalbed methane resources, but the degree of exploration and development is still at a low level, and the key path of efficient development of CNOOC coalbed methane is summarized by using contradiction theory and practical theory.
(1) Continue to consolidate the resource base. Drawing on the current experience of Zoomlion’s efficient development of multi-layer systems of medium and shallow coal seams, thin coal seams, and deep coal seams in the Shanxi-Shaanxi block, and taking the current practice of coalbed methane development as the leading path, we will seek breakthroughs in new coalbed methane blocks such as Xinjiang, Guizhou, and Yunnan along the “Belt and Road”.
(2) Accelerate the breakthrough of key technologies of the main body. It includes the concept of “complementary” and “three-dimensional” exploration, the excellent and fast drilling and completion technology of horizontal wells in complex formations, the large-scale reservoir transformation technology of horizontal wells, and the effective development technology of thin coalbed reservoirs, providing technical support and guarantee for the efficient development of coalbed methane.
(3) Efficiently coordinate the resources of all parties. Strengthen the deep integration of geological engineering integration, practice the concept of “new excellent and fast”, strengthen the interaction and interconnection of Party A and Party B, optimize the project management process, jointly improve the management level, better coordinate the resources of all parties, and improve development efficiency.
(4) Optimize the win-win sustainable development model. Including party building leadership, deep integration, digital and intelligent intelligent gas field construction, independent development, win-win cooperation, enterprise-local joint construction, high efficiency, energy saving, low-carbon environmental protection, help adapt to policy changes and environmental protection requirements, and achieve sustainable development.
(5) Strengthen the basic theory and key technological innovation of the integration of unconventional resources and geological engineering. With the breakthrough in the development of deep and thin reservoir coalbed methane, it is also necessary to break the inherent barriers and conventional thinking of oil companies, expand the horizontal cooperation between enterprises and universities and research institutes, increase the deep integration of science and technology industry-university-research innovation and geological engineering integration technology, and break through the bottleneck of basic theory and key development technologies of complex reservoir coalbed methane.
(6) The key path of efficient development of coalbed methane will help promote the synchronous development of the broad direction of efficient development of coalbed methane and technological innovation, strengthen the refined management of development, reasonably reduce development costs, improve the comprehensive efficiency of development, guide the basic theoretical innovation and development practice of CNOOC in the future, promote the construction of CNOOC coalbed methane production capacity to improve quality and efficiency, ensure stable production and production in the trillion-dollar atmosphere on land, and give full play to the leading role of CNOOC in the complementary development of shallow and deep coalbed methane, so as to help the national dual carbon goal and ensure national energy security.

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