Basic conception of intelligent open-pit mine construction

1 One of intelligent systems: intelligent system of open pit foundation support

The intelligent system (as shown in Figure 4) is an important cornerstone for the construction of intelligent open-pit mine, which mainly includes the construction of network environment, hardware environment and software environment. Including supporting the construction and operation of intelligent open-pit mine big data information network platform, comprehensive database system, communication perception facilities, network transmission, data warehouse, application support, high-performance computing, mass storage, information security and all kinds of intelligent terminal systems and other basic security systems]. Network environment construction mainly includes data communication and network security; Hardware environment construction mainly includes data center, control and command center and office environment construction; Software environment construction mainly includes expert knowledge base, big data foundation and analysis platform. The intelligent system of opencast mine foundation support provides a full range of services for the construction of various business systems in the later stage to ensure reliable data collection, transmission, storage, application, etc. And with the construction of the smart mine business unit, maintain a certain advanced nature, so as to escort the construction of the entire smart open-pit coal mine.

2 Intelligent system II: Intelligent system of spatio-temporal evolution of open-pit mine

The whole life cycle of an open-pit mine can be summarized as various stages before, during and after development. All behaviors of open-pit design, production and management are nothing more than the dynamic development and change of three-dimensional space-time of an open-pit mine. Therefore, intelligent construction is first to build a visual and digital dynamic model of three-dimensional space-time evolution of an open-pit mine. Dynamic record and query, display the surface mine resources development and environment at any time of the three-dimensional space form, equipment and process system layout and operation status, production planning, construction and management and other economic and technical status.

The intelligent system for the spatio-temporal evolution of open-pit mines (as shown in Figure 5) can collect and display all relevant data of geology, survey, safety and production, etc. All information of open-pit mines can be queried and visually reflected through the spatio-temporal evolution model. Such as the backtracking of the historical production status of the open-pit mine and simulation mining, testing the pros and cons of the production plan, verifying the incompatibility between the project implementation and the production plan, etc., to form the basis for visual analysis and intelligent application of the mechanical and electrical equipment management, production plan and project management system.

3 Intelligent system III: open pit equipment and process intelligent system

Intelligent planning of drill rig, mixed explosive truck, electric shovel, dump truck, soil discharge machine and raw coal ground production system (including crushing station, belt conveyor, stacker and reloader, loading station), etc., mainly realizes the digitization and automation of equipment operation process, remote control of operation link and intelligent operation. To achieve the goal of reducing repetitive simple work of field personnel and reducing field operators. The Internet of Things collects the operating conditions of devices, analyzes the correlation and measurement among devices, and realizes intelligent functions such as identification, comparison, analysis, transmission and receiving instructions [74-80]. It mainly includes:

1) Intelligent mining equipment. As shown in Figure 6, mining sensors, artificial intelligence and 3S (GIS, GPS, RS) and other technologies are used to realize the intelligent and accurate operation of the electric shovel, and the correct and reasonable position of the electric shovel and the reasonable mining mode of the bucket are determined during the operation process. Accurately identify rock size and coal-rock mixed steps, and transmit geological data to the production technology center in real time to make reasonable plans for the next advance of the working face; When loading, it can accurately identify the position of the truck and the accumulation shape of the materials in the bucket, provide guidance for the hover position of the bucket, and ensure the full load rate of the truck.

2) Intelligent transportation equipment. As shown in Figure 7, 3S (GIS, GPS, RS), sensors and other technologies are used to realize the positioning of large transport trucks, assignment of working position, planning of optimal transport routes, automatic docking in soil discharge operations and other functions, and realize unmanned truck driving under simple road conditions. The intelligent belt conveyor is used to realize the automatic detection and distribution of coal samples, automatic detection of material particle size, and adjustment of crusher speed; Research on the application of high Angle conveyor (tape or chain plate) in open pit coal mine to reduce the transportation cost.

3) Intelligent discharge equipment. As shown in Figure 8, the application of wireless remote control bulldozer in open-pit soil discharge operation is studied, and the full hydraulic bulldozer is operated unmanned in remote control mode. By using the global positioning system (GPS) and the sensors installed on the construction machinery to grasp the position of the bulldozer itself, the status of the shovel and the robot arm and the ground conditions in real time, the operation indication data is transmitted to the control box equipped with the construction machinery, and the construction can be confirmed by the measurement system while the construction is carried out.

4) Intelligent perforation blasting operation. As shown in Figure 9, the intelligent three-dimensional design system for open-pit mine blasting engineering is developed by using geographic information system, virtual reality, geostatistics and other methods, combined with rock blasting theory and blasting technology, to realize blasting parameter design, blasting process simulation and blasting effect prediction and analysis. The application of GPS, strapdown inertial navigation system and other technologies to achieve accurate positioning of drilling equipment, and real-time drilling position and depth verification, to achieve the intelligent and accurate operation of drilling rig.

5) Crusher (station) intelligent. As shown in Figure 10, the image recognition of material lumpiness, vibration sensing during crushing process, automatic control and adjustment of electrical appliances and other technologies are used to judge the shape and lumpiness of materials through real-time image processing, build a classification standard to distribute materials and statistically analyze the proportion of different lumpiness. Based on the real-time monitoring and judgment of the lumpiness of the material and the vibration frequency and amplitude of the crushing process, the feedback blasting effect is analyzed through the lumpiness. On the other hand, the feed speed, the crushing roll steering and the rotational speed are intelligently adjusted to achieve efficient operation.

6) Real-time intelligent diagnosis of equipment failure. The technology of high-speed synchronous acquisition and long-distance transmission of parameter signals is studied. Based on embedded technology, real-time analysis of massive data is studied to realize local real-time analysis of mechanical and electrical equipment faults. The feature extraction and quantitative intelligent diagnosis technology of equipment weak fault are discussed to overcome the over-dependence of equipment fault diagnosis on professionals. This paper discusses the remote centralized monitoring and diagnosis technology of electromechanical equipment to realize information sharing and multi-point access.

3.4 Intelligent system IV: Intelligent system for open pit production planning and project management

Based on the integrated logic relationship planning of production and construction, the intelligent system of open-pit mine production planning and project management mainly realizes the intelligent design of piercing, mining, loading, transportation and discharge links, deduction and analysis of local operation processes, refinement and quantification of key points in operation links, standardization of construction standards, automatic accounting of production costs and automatic performance assessment. The intelligent control of mine construction quality can realize the dynamic simulation of mining process, the interactive analysis and optimization of mining design and construction, and the automatic decision-making and construction of each process link under the optimal production target, and finally achieve the purpose of intelligent decision-making.

On the basis of intelligent equipment, combined with comprehensive scheduling optimization to achieve the optimal automatic decision-making of all process links under the optimal production objectives, and at the same time to achieve the intelligence of auxiliary production links, that is, to build a comprehensive intelligent supervision and decision-making platform of production process system (or called the open-pit whole system (man-machine environmental management) intelligent decision-making platform). According to the production objectives determined in time and stage (optimization objectives such as the lowest cost, maximum overall production capacity, etc.), apply the Internet of Things + to calculate the real-time spatial location, running track, operation status, intact condition of a single device, as well as various economic and technical indicators, etc., comprehensive scheduling optimization. The sub-objective optimization operation of the main process systems of perforation, blasting, mining, transportation and discharge is realized under the overall optimal goal. Accurate positioning, exchange and optimal matching between each device; Complete main information push at any time (ranking of key equipment performance, failure, performance assessment, etc.); Gradually extended to the intelligence of auxiliary production links: later cover the drainage, road maintenance, power supply maintenance and other auxiliary operating equipment.

Intelligent mine engineering, such as open-pit production plan, working face extension project, promotion project, development of transportation road construction, etc. Focus on the production organization and construction of intelligent engineering: According to the existing process equipment and design and the short and medium term plan, determine the best perforation, blasting, mining, transportation, discharge, road maintenance, reclamation and other works or production operations construction design/plan, the best technical parameters, equipment system layout and scheduling, personnel and material support, auxiliary works, etc.; The actual operation location, operation status, quantity and quality indicators and other information are collected/shared through the Internet/Internet of Things/big data, such as their location, operation conditions or inter-correlation and measurement, etc., and the intelligent operation process and management can be realized through identification, comparison, analysis, transmission and receiving of instructions [81-83].

3.5 Intelligent system V: Intelligent system for open pit integrated management

The intelligent system of open-pit integrated management is based on the data collected by the spatiotemporal evolution model, the data generated by the intelligent mechanical and electrical equipment and the data generated by production planning and project management. It adopts advanced technical means such as big data analysis, expert evaluation and expert system to study the intelligent management method of green, safe and efficient production. For example, fully automated analysis of production efficiency, real-time control of production costs, and ubiquitous performance appraisal can be achieved to maximize the production cost of open-pit mines. Realize the intelligent command of production equipment, the intelligent management of mine engineering and the intelligent optimization of process system, further realize the operation of fewer people, reduce or even eliminate the safety hazards of the open-pit mine itself, and realize the essential safety of the open-pit mine; Improve the quality of ecological reclamation, reduce the cost of ecological reclamation, realize the value of ecological restoration, realize the essence of open pit mining green, and finally realize the construction of harmonious, beautiful and sustainable development of open pit mine.

As shown in Figure 12, the intelligent system of integrated open-pit management realizes the comprehensive and centralized control of all intelligent systems in open-pit mines, including the intelligent management of mine personnel, finance, materials, safety and outsourcing projects. Intelligent management of auxiliary links such as ecological protection and energy conservation. Realize network-based cross-space network query, management, operation, scheduling, security, service and so on. Open-pit slope safety, network security, safety training, anti-collision technology and equipment, dust control, toxic and harmful substances management, rational use of dewatering water, clean energy utilization, large expert knowledge base and data warehouse, visual intelligent decision platform, intelligent decision platform based on big data, data communication, office automation, intelligent office environment.

4. Key technologies of intelligent open-pit mine construction

According to the hierarchical level of the system, the whole intelligent mine system is divided into three levels: intelligent unit, intelligent system and intelligent large system.

4.1 Intelligent unit level - Sensor hardware and software technology

The technical requirements of the intelligent unit are the technical requirements that need to be met when building a most basic intelligent open-pit mine unit. From the perspective of the architecture of the intelligent unit, the sensor is the source of the intelligent open-pit mine to obtain relevant data information, and is the primary link to realize automatic detection and automatic control. Therefore, at the intelligent unit level, the most core key technology is the sensor analysis technology that includes software and hardware.

4.2 Intelligent system level - unit communication technology

On the basis of the technical requirements of the smart unit, referring to the hierarchical architecture of the smart mine system, it is necessary to further emphasize the interconnection between the unit components, and on this basis, focus on the real-time and dynamic information control of different components, so as to achieve the coordination and unity of the information space and the physical space. At the same time, the integrated computing system, sensing system, control system and network system need to be unified management, so at the level of intelligent system, it needs the support of unit communication technology.

4.3 Intelligent large system level - system integration technology

Based on the technical requirements of the intelligent system and the hierarchical structure of the intelligent mine system, the data of the intelligent large system is more real, rich and diverse, so a new processing mode is needed to integrate and analyze the data to extract the potential value, so as to provide stronger decision-making power, insight and process optimization ability. Then systematic and comprehensive mining mining data in the potential value. Therefore, at the level of intelligent large systems, the support of system integration technology is needed [90-93].

To sum up, the hierarchical structure of the smart open-pit mine and the core key technologies required by each level are shown in Table 1.