Mineral resources are an important material basis for the survival and development of human society. Drilling is an important engineering method and technical method used by humans to develop mineral resources. In deep prospecting work, in addition to using more effective geological theories as guidance and applying more advanced geophysical prospecting, geochemical prospecting, remote sensing and other new detection technologies and methods, drilling is still the most basic and important detection method to achieve final results.
7.1.1 Main technological progress in deep hole drilling
Since the 21st century, my country has entered the stage of scientific drilling and deep hole drilling. In order to ensure the realization of the goal of deep geological prospecting, a number of major scientific research and technical research results have been carried out around deep hole drilling. The main technological progress is as follows.
(1) The development of deep hole drilling equipment, machinery and instruments has achieved fruitful results
1) XY-6B, XY-8, XY-9, FYD-2200, KZ3000 The successful development and application of vertical shaft type deep-hole, fully hydraulic power head core drilling rigs and mud pumps such as BW300/12A, BW300/16, BW280/30, BW160/10 and BW240/9 have greatly improved drilling capabilities and drilling capabilities. The efficiency has been greatly improved.
2) SQ series wireline coring drill pipe hydraulic tongs, hydraulic clamps, wireline coring elevators, and single-cylinder self-centering hydraulic extruders for handling accidents and other orifice auxiliary devices, The successive introduction of tools has initially formed a mechanized system for orifice operations.
3) The SYZX series of wireline coring hydraulic hammer drilling tools have made breakthroughs in simplifying the structure, improving the working life and reliability, greatly improving the drilling efficiency and footage, improving the core recovery rate and The quality of drilling makes my country's application technology in this field at the international leading level.
4) New breakthroughs have been made in the development and application of Φ73 mm and Φ89mm wireline coring drill pipes and long-life new diamond drill bits for XJY-850 high-grade alloy pipes.
5) A high-precision drilling parameter monitoring system with working condition identification, accident alarm, parameter storage and wireless remote transmission functions has been successfully developed and applied, such as the CUG-2 full-scale drilling system developed by China University of Geosciences (Wuhan) Hydraulic drilling rig drilling parameter monitoring system.
(2) Scientific drilling leads to new breakthroughs in deep hole drilling technology
Since the 21st century, in order to improve the understanding of the earth and improve the level of resource exploration and disaster early warning in our country, our country Major scientific drilling projects such as "China Continental Scientific Drilling" (5118.2m), "China's Cretaceous Continental Scientific Drilling Songke 1 Well" (South Well 1915m, North Well 1811.18m) and "Wenchuan Earthquake Fault Zone Scientific Drilling" were successively launched. The implementation of the scientific drilling project not only established a new scientific drilling technology system with Chinese characteristics, but also achieved innovative results that have great guiding significance and application value for deep hole drilling, such as: combined drilling technology, screw motor hydraulic hammer Bottom-hole power-driven coring drilling technology with dual-tube coring drilling technology as the core - three-in-one drilling tools (screw motor + hydraulic hammer + wireline coring), two-in-one drilling tools (hydraulic hammer + Wireline coring), well inclination control and deflection drilling technology in strongly deviated formations based on rigid, straight, full and heavy bottom hole assembly and diamond drill bit reducing sidetracking technology, integrated guide cone The drill bit's large-diameter reaming drilling technology for long well sections in hard rock, single-action three-pipe conformal sampling drilling technology for loose sand layers and semi-joined pipe coring drilling technology for broken rock layers are installed with small gap casing and movable casing. Casing cementing technology characterized by recovery and recovery, prevention and treatment of in-hole accidents, and drilling data collection and processing, with "vibrating desander + high-speed centrifugal desander centrifuge + 30m circulation tank + sedimentation tank + slurry delivery tank" Mud purification measures, etc.
(3) Positive progress has been made in the research and development of new flushing fluid systems
The successful development and application of new mud materials and leakage plugging materials have paved the way for the implementation of deep hole drilling and the implementation of advanced technology. The application provides certain material guarantee and technical support.
1) Five new flushing liquid treatment agents: high-efficiency lubricant (GLUB), non-dispersing high-temperature polymer diluent, high-efficiency wall protecting agent, KL vegetable gum and grafted starch polymer.
2) Five new flushing fluid systems: PHP-GSP solid-phase flushing fluid system, GSP low-solid flushing fluid system, biopolymer solid-phase flushing fluid system, and low friction resistance salt intrusion flushing liquid system and KL vegetable gum type environmentally friendly flushing liquid system.
3) New plugging materials: LHDLX plugging king and SZ plugging while drilling, anti-collapse plugging agent while drilling (GPC), composite plugging agent (CBM), high Water loss plugging agent GSDL, etc.
4) The TGLW350-692T mud solid control centrifuge developed by Beijing Exploration Engineering Research Institute has been used in deep hole rope core drilling and achieved good results.
(4) Significant progress has been made in the formulation and revision of drilling technical regulations, specifications, and standards
For example: "Geological Core Drilling Regulations" (DZ/T0227-2010) as the land and resources industry The technical standards were released on November 11, 2010 and implemented on December 31, 2010.
7.1.2 Overview of key technologies for deep hole drilling and their research
The research and solution of key technologies for deep hole drilling is an urgent and important new topic for core drilling. Deep hole core drilling has the characteristics of large drilling depth, many technical problems, strict quality requirements and high drilling costs. Compared with general core drilling, in addition to the need to be equipped with a high-power deep hole drilling rig, a reliable variable pump, and the ability to withstand high loads In addition to drilling towers and other equipment, there are also many technical problems related to drilling quality, drilling safety, mechanical drilling speed, etc. that need to be discussed and solved. When carrying out deep hole drilling in mining areas under complex geological conditions, there are more constraints and it is more difficult to solve problems. For example, the geological conditions of deep strata are unclear and there is a lack of experience for reference; the drilling structure is restricted, and under complex geological conditions The technical problems of wall protection are more prominent and severe; deep hole tripping operations take a long time, and various in-hole accidents are more likely to be induced and worsened; etc. Therefore, in order to make deep ore body exploration and drilling high-quality, efficient, safe, low-cost and effectively reduce the overall drilling cost, the key technical issues of deep hole drilling should be studied and solved according to the rules of deep hole core drilling, and relevant drilling technology and methods should be carried out. Optimization discussion.
(1) Main key technologies for deep hole drilling
As we all know, deep ore body exploration drilling will encounter more technologies than shallow and medium-deep ore body exploration drilling. problem. According to the solid core drilling survey of the Fujian Provincial Geological Prospecting Bureau, due to insufficient research on deep hole drilling process methods and single technical measures, when the drilling depth exceeds 800m, the accident rate in the hole often increases and the drilling efficiency decreases significantly. Drilling costs have doubled.
my country's geological core drilling has experienced more than 60 years of development. Although the technical level has reached a very high level, with numerous drilling scientific research results and rich drilling experience, deep ore body exploration and drilling has not There are many technical problems that need to be solved urgently, such as: insufficient equipment capacity, inability of machines to work properly, the impact of shallow goafs on exploration, difficulties in retaining walls and coring in complex formations when the hole depth is large, and the experience of medium-deep drilling Problems include ineffective application of methods, difficulty in handling accidents in the hole, and low drilling efficiency. Therefore, it can effectively solve the problems of low comprehensive drilling efficiency in drilling deep holes (hole depth ≥ 800m), wall protection and plugging of complex formations when the hole depth is large, difficulty in extracting rock cores, and excessive hole inclination, which directly affect geological prospecting and exploration. The technical and technological methods that solve the main problems of results and benefits constitute the key technology of deep hole drilling.
Looking at the deep hole drilling for iron ore exploration across the country, due to the complexity of the strata, the problem of hole protection and leakage has become the main technical problem that restricts the results of iron ore exploration.
(2) A brief introduction to the research on key technologies of deep hole drilling
Deep hole core drilling generally faces the difficulties of wall protection and plugging in complex formations, low rock core recovery rate, excessive hole inclination, Major technical problems such as slow drilling speed directly affect the results and benefits of geological prospecting and exploration. Therefore, relevant drilling units and scientific research institutions have carried out key technology research and research in combination with scientific drilling and deep hole drilling.
The Exploration Technology Research Institute used the "2000m geological core drilling key technology and equipment" ("863" key project) project undertaken by the Institute to successfully apply the YDX-5 fully hydraulic geological core drilling rig and N-level caliber (Φ76mm ) The rope coring drilling tool constructed the ZK43-1 hole in the Jinqingding Gold Mine in Rushan, Shandong Province (on April 10, 2010, the final hole depth reached 2212.8m), creating the first H-class diameter (Φ95mm) rope coring The drilling tool drilled 1461.9m and drilled Φ91mm×4.5mm technical casing to the same depth, which were the two deepest records at the time; the Anhui Province 313 Geological Team will undertake the key scientific and technological research project of Anhui Province "Research on Deep Ore Body Exploration Drilling Technology and Methods" Combined with the deep prospecting project of Huoqiu Zhouji Iron Mine in Anhui Province, we researched and solved the drilling problems of complex stratigraphic conditions such as water inflow, water leakage, and collapse in the borehole. After one year, the ZK1725 hole was completed on June 28, 2010. The construction set a record for the deepest small-diameter rope core drilling in China at that time (final hole diameter 77mm, final hole depth 2706.68m); in November 2010, the Third Geological Exploration Institute of Shandong Provincial Bureau of Geology and Mineral Resources undertook the "design hole depth of 4000m" In the "China's First Deep Drilling for Rock and Gold Exploration" drilling project (Xiling Mining Area, Sanshan Island, Laizhou City, Shandong Province), a series of drilling scientific research and key research work were carried out based on the stratigraphic characteristics of the drilling and the technical difficulties encountered during drilling; July 2009 As of December 2010, the "Research on Optimization of Technology and Methods for Deep Ore Body Exploration and Drilling" scientific research project approved and carried out by the Fujian Provincial Bureau of Geology and Mineral Resources has also comprehensively collected, digested and absorbed previous research results in response to technical difficulties encountered in drilling, and has initially carried out Discussions on leakage plugging strategies and technical measures for long hole sections and multi-characteristic complex formations were conducted.
There is no doubt that special drilling research or technical research based on the characteristics of deep holes has effectively supported the development of deep prospecting geology. It has not only continuously set domestic core drilling hole depth records, but also provided a The research has left a wealth of valuable experience, but so far no research results have been seen that can effectively solve the technical problems of drilling complex formations in iron ores.
(3) Optimization research on drilling technology
In the 1980s, with the increase in the number of drilling projects across the country and the development of drilling technology, many professionals To meet the needs, FTA analysis, variance analysis, analytic hierarchy process (AHP), gray situation decision-making comprehensive evaluation, geometric planning, fuzzy optimization and other theories were used to carry out research on drill bit types and structures, wall protection mud countermeasures and formulas, drilling technical parameters, etc. Optimizing selection improves drilling efficiency, reduces in-hole accidents, reduces drilling costs, promotes the improvement of drilling technology and technology, and also provides relevant experience for this study. However, the main applications and results of previous work research are basically the optimization of a single technology process, and the drilling depth is not large (generally less than 700m).
my country’s first continental scientific deep drill conducted a technical and economic analysis of lift-drill coring and rope coring based on the special requirements of scientific drilling for rock cores, and carried out diamond rope coring and drill bit bottom-hole motor driving. Comprehensive research on drilling methods such as , percussion and rotation, their drill tool combinations, and the optimization of drilling parameters have achieved good results. This is the first time that China has effectively explored the optimization of deep hole drilling technology and methods.
In 2007, Dr. Zhang Wei, Director of the New Technology Division of the Department of Science and Technology and Foreign Affairs of the China Geological Survey, combined with the practice of scientific deep drilling in mainland China, believed that “carrying out technical economics research can achieve the optimization of technical solutions and technical measures. To point out the direction for research and development work so that the implementation of drilling projects can achieve the best economic results", the theory of "drilling technology economics" was proposed. This theory provides working ideas for the research on the optimal combination of drilling technology and process methods, builds a system framework and lays a theoretical foundation.
(4) Research directions of the main key technologies of deep hole drilling
Looking at the domestic special research or technical research on deep hole drilling, most of them are to ensure the smooth progress of deep ore body exploration. It is carried out based on the stratigraphic characteristics and certain problems in the mining area. Due to the lack of systematic and comprehensive consideration, the cost is often heavy or the situation in the hole is complicated, resulting in the drilling time of a single hole lasting half a year, a year, or even longer. It is not uncommon.
Due to the constraints of the topography, stratigraphic lithological characteristics, hydrogeology and engineering geology, operating environment and other conditions, the drilling construction of deep ore body exploration must be based on the design purpose and purpose of deep ore body exploration drilling. Drilling requirements require a reasonable, effective and optimal combination of technical and organizational measures such as drilling tools, drilling structures, drilling methods, drill bits, mud, drilling technical parameters and organizational management measures to achieve high drilling speed, fewer accidents, Good quality, low cost and other goals.
Therefore, due to the particularity of deep ore body exploration, in order to solve the technical problems encountered reliably, effectively and at low cost, deep hole drilling is regarded as a complex system engineering and various factors and conditions are comprehensively considered. Research on the optimized combination of process technology methods is the development direction, that is, in addition to formulating technical and process measures to solve problems through scientific research or research work (including the development and application of new technologies, new processes, and new methods), it is also necessary to target deep Optimize the geological characteristics of ore body exploration drilling and select effective technical measures and their combinations.