Dong Ming Guo

Energy Consumption Analysis of Level Circulating Cooling System in Sanhejian Deep Coal Mine

With the deep mining in coal mine, heat damage is one of the technical issues need to be solved. HEMS cooling system in Sanhejian Coal Mine is a process system for high-temperature heat damage controlling in deep coal mine, in which cool energy extracted to reduce work face’s ambient temperature to achieve heat damage controlling. Part of the cool energy is from the level circulating of cooling water in -700 level main raodway, the other is from the mine water. We analyze the energy consumption of every subsystem during operation of the HEMS system, which could provide a theoretical basis and technical guidance on more efficiently running of cooling system deep in the future.

Research of the Best Combination of Cooling Parameters in High Temperature Work Deep Stope

When designing cooling engineering in deep stope, the three parameters, air temperature, air velocity and distance between cooling air and work place, are three key factors to determine cooling effect. Lowering air temperature, increasing air velocity and shortening the distance between cooling air and work place can all achieve the purpose of cooling work place. Not only to achieve the purpose of cooling, but also to reduce operating costs, save energy and extend the service life of cooling equipments, these three parameters should be chosen and combinated rationally, to gain the fine operation conditions. Taking 7446 work face in Jiahe coal mine as an example, on the base of analysis of multiple sets of cooling parameters in a variety of conditions, it proposes the range of parameters which can gain better cooling effect, more economical run and longer cooling equipments service life. It provides a wider choice of reasonable parameters for 7446 work face cooling engineering.

Experimental Study on Impermeability and Frost Resistance of High Strength Concrete Used in Shaft of Coal Mine

This paper presents results of impermeability and frost resistance tests of a series of high strength concrete which will be used in Yuncheng coal mine shaft lining. And the shaft is one of the most difficult to construct using freezing method because of the extreme thick overburden soil. The results show the impermeability and frost resistance of the selected concrete mix proportion options can meet the special requirements of the shaft construction. It’s due to the low water-cement ratio, admixture and water-reducing agent decreases void caused by excess water. And the composite mineral admixture forms bubbles to cut off the tiny water permeable channels in cement stone. Also the filling effect and pozzolanic effect caused by fly ash contribute a lot. The research on high strength concrete used in shaft of coal mine with thick overburden soil is still rare worldwide.

Physical Model Test on Thick Gravel Layer Inclined Shaft Deformation and Failure in Yili No.1 Coal Mine

There exists a thick layer of gravel in Quaternary alluvium surface soil layer in most areas of Xinjiang, China. When passing through the gravel layer during mine construction, mine workings collapse and rib spalling often happen, which influences the mine working’s construction and bring hidden danger to safe construction. This article took the engineering geological characteristics of thick gravel layer in Ili mining area in Xinjiang as background, carried out the gravel layer roadway’s deformation and failure tests based on the principle of similar model test, and analyzed and summarized the law of the surrounding rock deformation and failure. The results indicates that: Seepage is the decisive factor in the destruction of gravel layer surrounding rock; roof displacement increased from 1.8mm up to 3.4mm when the gravel layer roadway surrounding rock’s water content grows from 7% to 12.67%, which shows that displacement of surrounding rock increased with the increase of water content; coupling support has the best effect in gravel layer roadway. The research results play a guidance role and have a reference value for the engineering with the same type of roadway design and construction.

Combination of Coal and Rock Uniaxial Compression Test Image Processing of CT

The use of industrial CT systems, and special loading equipment, combination of coal and rock under uniaxial compression load test real-time CT scan obtained at different loads under various stages of the CT images. Using digital image processing technology to coal combination of the CT image gray stretch and pseudo-color enhancement to improve image contrast, highlighting the cracks and pores of the edge information. To establish a combination of coal to the coal from the rock micro-crack interaction and its associated macro-deformation, further study coal - roof and floor damage and the impact of mechanical systems to the mechanism of pressure to provide experimental basis.

Temperature Field of Single-Well Aquifer Thermal Energy Storage in Sanhejian Coal Mine

The technology of aquifer thermal energy storage(ATES) is an energy-saving technology which can provide a solution to energy shortages and resources expasion. The first key point of this technology is whether the aquifer can be use to store energy. In this paper, taking Sanhejian Coal Mine as an example, we choose Quaternary upper loose sandy porosity confined aquifer to bottom clayed glavel porosity confined aquifer as aquifers thermal energy storage, to discuss whether the aquifers can be used to store energy. The simulation results of aquifer temperature field show that the selected aquifers reach the goal of energy storage. And with the same irrigation flow, the lower the temperature, the more the cold water and the larger the low temperature region in aquifers thermal energy storage. With the same irrigation temperature, the lager the irrigation flow the more the cold water and the larger the low temperature region in aquifers thermal energy storage.

Utilization and Research on Medium-Enthalpy and Low-Enthalpy Geothermal Energy in WSHP System

Geothermal energy is a stable energy, stored underground and not influenced by the geographical, seasonal weather and the change of day and night. Medium-enthalpy and low-enthalpy geothermal energy are distributed in many areas of China, having a broad prospect for development. Taking water resources heat pump (WSHP) engineering in Tianqiao District as an example, medium-enthalpy and low-enthalpy geothermal energy is combined with the technology of aquifer thermal energy storage (ATES), providing cold energy in summer and warm energy in winter for the buildings. On the base of analysis of hydrogeological conditions in Tianqiao District, the temperature field of energy storage aquifers is numerically analyzed in the period of heating and cooling. The results show that the energy storage well can meet the requirement of heating and cooling conditions. The system of WSHP greatly utilizes medium-enthalpy and low-enthalpy geothermal energy, making the running costs economical.

Effect of Cold Energy Storage of Multi-Wells Aquifer Thermal Energy Storage in Sanhejian Coal Mine

Effective implementation of technology of aquifer thermal energy storage (ATES) must form a ground cold water reservoir or ground warm reservoir. In this paper, taking Sanhejian Coal Mine as an example, we analyze the effect of cold energy storage in single-well by analyzing the volume change of cold water body within different temperature ranges. Through the analysis of volume change of cold water body, it can prove that with the same irrigation temperature, the increase of irrigation flow makes the volume and percentage of cold water body in aquifer within different temperature ranges. And the impact on the cold water of 2-5°C is more obvious. With the same irrigation flow, both the cold water body and its percentage of 2-10°C in the condition of 2°C irrigation temperature are more than those in the condition of 5°C. The increase of irrigation flow and the decrease of irrigation temperature are beneficial to cold energy storage, and the effect of cold energy storage of the condition 3 (100m3/h irrigation flow and 2°C irrigation temperature) is the best in these four conditions.

Design and Field Test of Bolt-Mesh-Cable Support of Extraction Drift in Soft Thick Seam with a Large Angle

Considering the poor support results of extraction drift in soft thick seam with a large angle in Dujiacun Mine, and there’s no similar design in such engineering geological conditions. Firstly, determined surrounding rock stability classification of the drift and obtained that roadway surrounding rock of this mine is type. According to the approximate range of this type roadway surrounding rock, selected parameters of bolt support, then using FLAC3D software simulated support effect of the roadway with different parameters of bolt support, analyzed the extent of the support effect of various parameters. The simulation results show that the optimal program is φ2200mm round steel bolt in the roof andφ2500mm equal strength thread steel in the two sides. Monitoring results of ground pressure displacement of surface, load of bolt and amount of roof separation show that bolt-mesh-cable support is safe and effective.

Thermal Environment Simulation of Buildings on the Ground in Low Enthalpy Geothermal Engineering

By using a variety of energy-saving technologies, low-grade geothermal energy will be efficiently used for improving the indoor thermal environment with few high-grade electric energy in low enthalpy geothermal engineering. In order to be more targeted and precise, geothermal energy conservation engineering should be designed and controlled on the basis of characteristics and variation of indoor thermal environment. Taking the low enthalpy geothermal engineering in the Air Force Command Academy veteran cadre living area as an example, it generalizes the building and simulates the indoor thermal environment by DeST software. The results show that the thermal enironment of rooms which are on the different storeies and different orientations is different. it is be obvious regularity, the thermal enironment of rooms in the high storey and low storey is worse than the middle storey in winter, the thermal enironment of rooms in north is worse than in south, the thermal enironment of rooms in west is worse than in east, and the thermal enironment of rooms in the corner is worse than in the middle. All of these may be a guide to equipment selection, layout of pipe network and terminal equipment, and can provide a theoretical basis for energy conservation design and operations control.