L. V. Kuznetsova’s research while affiliated with Russian Academy of Sciences and other places

Today, millions of tons of coil remain in the subsoil and are written off as losses. These include hard-to-recover reserves unfit for mining with traditional high-performance means of integrated mechanization. One of the all-purpose technical solutions to the problem of developing such reserves can be technologies using robotic mobile mining equipment based on a heading-and-winning machine and a self-propelled car. Flowcharts for coal deposit development have been designed for seams unfit for mining with integrated mechanization means (medium thick seams, thick seams, flat and steeply inclined seams). These include open-pit and underground mining of marginal reserves from the side of the pit wall and limited reserves from the daytime surface performed by mobile mechanization means. During the operation of these means, the following process operations are repeated: coal breaking, loading into a self-propelled car, transportation along a preset trajectory, unloading into a reloader or other transport vehicle, or a warehouse on the bench. These operations can be robotized, which will increase both the safety and efficiency of coal mining. In order to perform coal-mining operations without constant attendance of maintenance staff, the existing mechanization means must be retrofitted with machine vision and a remote control system. Moreover, a robotized control system for the set of equipment must be developed to resolve the following problems. For the heading-and-winning machine: transportation (feed) along a straight line; transportation along the preset curve (formation of a diagonal entry); coal breaking at the preset thickness; coal breaking within coal-rock boundaries or along a preset cross-sectional contour; loading of broken coal into a self-propelled car; and control of the car loading level. For a self-propelled car: transportation along a preset trajectory from the loading point to the unloading point; control and management of the completeness of loading (unloading).

Introduction. When developing coal deposits using underground method, the greatest success was achieved for the seams with the thickness of up to 7 m by means of complex mechanization in one layer. The productivity of a cleared face reaches 6–8 thousand tons per day. A method of coal extraction from the top coal layer is used to mine seams of greater thickness. The limiting factor is the inability to control of the extraction process and, as a result, significant operational losses. Objective. The research aims to develop promising technologies for efficient and safe mining of thick flat coal seams using a robotic complex with controlled extraction from the top coal layer. Methods. The research is based on the analogy method. Results. By closing the gates installed on the extended sides of the line conveyor sections during the operation of the coal cutterloader and opening them during the release of coal, penetration of the loosened coal into the “pockets” of the support sections is eliminated. This reduces the operational loss of coal, the likelihood of “floating” sections of the support, as well as risks of emergencies. Due to the presence of an additional bunker on the side of the mined-out space, the coal from the top layer is collected, temporarily withheld, and then gravity fed into the outlet opening. Elimination of the advance preparation of the top coal layer in the area above the planned break-down chamber prevents man-induced discontinuities inside the rock mass above the breakdown chamber, which increases its stability. Construction of the break-down chamber with an inclination against the working face provides a sequential introduction of the support sections into the break-down chamber, one at a time, which allows timely preparation and release of coal.

In the development of coal deposits, the leading place in the world is occupied by an open-pit mining method. However, millions of tons of coal in the coal mines sides are written off as losses. To refine such reserves, the Metec miner system technology, widely known in the world, is used — Deep Reservoir Development Complex. Often the top of the developed formation has local discontinuities, which are also formed as a result of drilling and blasting operations. The exposure of these local violations leads to the occurrence of emergency situations, namely, the collapse of the roof rocks into the conducted part of the excavation chamber, and the inability to extract the equipment of the complex. The Institute of Coal of the Federal Research Center of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences (Kemerovo) developed a design of a mechanized walking support, which can be used to refine coal reserves from the side of the mine by means of the complex in order to ensure safe working conditions and prevent unauthorized dumping. On the working platform, built at the level of the soil of the developed reservoir, the equipment of the complex is mounted, including, in particular, the cutting body and the screw conveyor. After notching the cutting body into the coal seam and forming the mouth of the working, the walking support is mounted, placing it behind the cutting body. By means of technical vision installed on the walking support, the condition of the roof of the mine is diagnosed as it is exposed. Maintenance of the roof of the formation in the zone of possible rock fallout is carried out by a walking support, operating together with the complex, which ensures not only a reduction in the accident rate of the face, but also an increase in safety and efficiency of the coal mining. At the end of the extraction of coal in the conducted chamber, the walking support can independently exit the working without interfering with the extraction of the equipment of the complex, or it is forcibly removed to the working site after the expansion force is removed from all the hydraulic racks, for example, by a winch.

A combined opencast-to-underground mining method is widely used for final extraction of border zone coal reserves and extracting areas with limited and non-technological reserves. The idea of the method is that coal is extracted by opencast method and continued by underground mining using highwall mining complex, mobile mining mechanical equipment, augers, mechanized complexes and water jetting facilities.

The technology of thick seam development with roof coal release on the face conveyor which allows increasing the coal flow, reducing the losses and stand-by-time of the stope is worked out by the Institute of Coal of FRC CCC SB RAS. Disintegration of roof coal preparing it for release can be done during gradual advancing of a stope or in advance, applying the method of interval hydraulic fracturing before starting stoping.

Significant coal resources situated in open-pit recovered sides and bottom being non-demanded are considered to be irretrievably lost and written off as losses. Integrated (open and underground) technologies for final extraction of contour reserves applying a highwall miner complex and mobile mechanical equipment which improve coal recovery ratio are introduced in the article.

Some kinds of coal in Kuzbass are metalliferous and should be used to the best advantage both as fuel and as a source of valuable components recoverable from ash and slag. It is proposed to initiate a production system composed of a coal mine, heat power plant with multi-stage coal preparation for combustion and a waste treatment plant for: furnace refuses and light-end products in the form of pregnant solution and fly ash.

The urgency of the problem. Sapropelite coals of the Barzas deposit of Kuzbass are good raw materials for producing liquid fuel, lubricating oils, paraffin, etc. Apart from that, they are enriched with molybdenum, niobium, rubidium, yttrium and titanium. The content of these deposits is higher than the minimal content, which determines the industrial importance of coal as a source of ore raw materials. However, until now, the field is not being developed because of the economic inexpediency and the lack of a solution to the problem of recycling of incineration and semi-coking waste, which have high ash content and a large volume. The purpose of the study: to develop the concept of integrated development of the Barzas sapropelite coal deposit on the basis of creating efficient, environmentally friendly and low-waste production. Research methodology. The analysis of geological and mining conditions of the formation, which is called the Main, the results of its geochemical studies of existing technologies of mining and processing the high-ash solid fuels. The promising areas of their development were also considered. Cluster approach to the development of sapropelite coal deposits. Results. Coal mining at the sites with different geological conditions can be carried out with openly-underground mobile means of mechanization. The First mine field can be developed by the underground way on the development system called “Long poles along the strike”. This can be attained by means of the comprehensive mechanization of the Second mine field. Also, “Long poles along strike, take out the strips by the drop” are combined sections of a mechanized roof support with mobile means of cutting and transportation of coal – the Third mine field. The energy-chemical cluster of the Barzas deposit of sapropelite coals is a complex of the enterprises, which are technologically connected among them. They are concentrated on the same territory, which includes the enterprises for extraction of coal, semi-coking plant, boiler room, the chemical enterprise for processing of ash-slag from burning of waste of pyrolysis. The enterprise for receiving ore raw materials and construction materials are also among them. Summary. The organization of the main processes (from coal mining to commercial production) within the framework of the energy chemical cluster will create an efficient, environmentally friendly and low-waste production. The consumer value of the obtained commodity products (resin, pyrogenetic water, fuel gas, thermal energy, ore concentrate and building materials) will be much higher than the cost of raw high-ash coal.