There is provided a ventilation apparatus with counter-rotating impellers driven by long shaft, wherein an electric motor and a gearbox are placed outside the air duct by using a long shaft with an internally disposed slim shaft extending therefrom, and are connected with the first stage impeller and second stage impeller inside the air duct by using the long shaft and slim shaft extending therefrom. In this ventilation apparatus with counter-rotating impellers, the components of the ventilation apparatus are placed inside and outside the air duct respectively by using the transmission shaft, which is convenient for maintenance and operation. By remotely arranging the impellers at an axial distance, the hub of the impellers will no longer be affected by an internally disposed electric motor, so as to reduce the ventilation resistance to ventilation. The impellers can be switched between the single impeller rotation and the counter rotation of two impellers.

A longitudinally yieldable support for underground roof support includes first and second outer shell portions having a first wall thickness and a third outer shell portion having a second wall thickness that is greater than the first wall thickness. The support is filled with a solid compressible filler material. At least one air ventilation tube extends between opposite sides of the third outer shell portion to allow a flow of air through the support as the first and second outer shell portions and filler material therein yield under load.

The present disclosure relates to the technical field of mine ventilation, and in particular, to a three-dimensional ventilation method and system for mining by 110 construction method in coal and gas outburst mines. The three-dimensional ventilation method comprises: constructing a first process roadway and/or a second process roadway before stopping the working face; forming a first roof-cutting and roadway retaining section by a part of the working face track gate located in the goaf, and/or forming a second roof-cutting and roadway retaining section by a part of the working face transport gate located in the goaf during the stopping process of the working face, so that the air inlet of the first roof-cutting and roadway retaining section enters the gas drainage air return roadway through the first process roadway to form return air, and/or the inlet air of the second roof-cutting and roadway retaining section enters the gas drainage air inlet roadway through the second process roadway to form return air, the three-dimensional ventilation system is constructed by using the gas drainage air inlet roadway and the gas drainage air return roadway, during the conversion from the 121 construction method to the 110 construction method, a complete ventilation system can be formed in the roadway retaining section, real-time monitoring of the roadway retaining section can be carried while eliminating harmful gas accumulation in the retaining section.

A mining method is provided without coal pillars with roof-cutting and roadway retaining. This includes, comprising: constructing a gas drainage roadway and eliminating outbursts in a working face transport gate area and track gate area on opposite sides of a first mining working face; constructing various components with an air return roadway. Another end is communicated with the gas drainage roadway by the first process roadway, one end of the working face track gate is communicated with the air return roadway, the other end is communicated with the gas drainage roadway. A ventilation system is formed. This makes full use of the existing gas drainage roadway to meet the roadway layout requirements using the 110 construction method, increasing the use function of the roadway and increasing the reuse rate of the roadway, reducing the roadway engineering quantity before production, shortening the construction period and reduce the cost.

A mining method is provided without coal pillars with roof-cutting and roadway retaining. This includes, comprising: constructing a gas drainage roadway and eliminating outbursts in a working face transport gate area and track gate area on opposite sides of a first mining working face; constructing various components with an air return roadway. Another end is communicated with the gas drainage roadway by the first process roadway, one end of the working face track gate is communicated with the air return roadway, the other end is communicated with the gas drainage roadway. A ventilation system is formed. This makes full use of the existing gas drainage roadway to meet the roadway layout requirements using the 110 construction method, increasing the use function of the roadway and increasing the reuse rate of the roadway, reducing the roadway engineering quantity before production, shortening the construction period and reduce the cost.

A mine cooling and dehumidifying system includes a compressor, a gas-liquid separator, an evaporator, a condenser and an expansion valve. The evaporator is in an air supply well, and the condenser is in a return air well; the compressor, the gas-liquid separator and the expansion valve are all between the air supply well and the return air well; an inlet of the compressor is connected to a refrigerant outlet of the evaporator through the gas-liquid separator, and a refrigerant inlet of the evaporator is connected with an outlet of the expansion valve; an inlet of the expansion valve is connected with a refrigerant outlet of the condenser, and a refrigerant inlet of the condenser is connected with an outlet of the compressor. In the present disclosure, by vapor compression type refrigeration cycle, the downhole air heat is transferred to the return air and then discharged to the ground.

A mine cooling and dehumidifying system includes a compressor, a gas-liquid separator, an evaporator, a condenser and an expansion valve. The evaporator is in an air supply well, and the condenser is in a return air well; the compressor, the gas-liquid separator and the expansion valve are all between the air supply well and the return air well; an inlet of the compressor is connected to a refrigerant outlet of the evaporator through the gas-liquid separator, and a refrigerant inlet of the evaporator is connected with an outlet of the expansion valve; an inlet of the expansion valve is connected with a refrigerant outlet of the condenser, and a refrigerant inlet of the condenser is connected with an outlet of the compressor. In the present disclosure, by vapor compression type refrigeration cycle, the downhole air heat is transferred to the return air and then discharged to the ground.

A tunnel ventilation system located in an upper section of a tunnel has a ventilation section divided into two or three ventilation ducts. One or more of the ducts are connected to reversible fan units so the ducts can serve as either an air infeed or an air exhaust system. The ducts contain a series of remotely controlled flaps which can be opened to ventilate different tunnel zones or closed to isolate other parts of the tunnel. Air blowers at tunnel entrances create an air screen that prevents unintended air circulation into the tunnel. Heat, smoke and other sensors and a software control system enable the system to detect smoke and fire, then to isolate and control ventilation in the fire zone. A fire suppression system using low oxygen air or other fire suppression fluids to blanket and smother the fire operates in conjunction with the ventilation system.

An overcast system to block an intersection between two or more mine passageways so as to prevent the mixture of intake air with return air. The overcast system includes a first sidewall formed of one or more prefabricated panels, a second sidewall formed of one or more prefabricated panels, and a top member formed of one or more prefabricated panels, such that the top side spans the width between the first sidewall and the second sidewall. A fire-resistant coating is applied to at least a portion of the first sidewall, the second sidewall, or the top member to provide an air-tight, fire-resistant structure. Each of the one or more prefabricated panels is formed from a composite material having one or more structural studs embedded at least partially therein.

A modular controlling system for controlling and/or interfacing sophisticated power, communication, monitoring, lighting, ventilation and/or other services systems in complex environments such as underground mines, pharmaceutical laboratories and production facilities and nuclear plants comprises a main processing unit, several communication interface units, several equipment interface units, and a user interface unit. The modular controlling system is configured to be installed in a complex environment such as an underground mine and connected to various mining equipment, including ventilation equipment and environmental sensors. The modular controlling system is generally preprogrammed and preconfigured with all the necessary operating programs, control algorithms and equipment drivers such as to required minimal customization upon installation.