Energy efficiency improving type mining anti-explosion refrigerating unit

Abstract

The utility model discloses an energy efficiency improving type mining anti-explosion refrigerating unit which comprises a screw compressor, an oil separator, an oil cooler, a condenser and an evaporator, and is characterized by further comprising a heat regenerator, a refrigerant output end of the condenser is connected with a hot end medium inlet of the heat regenerator, and a refrigerant output end of the oil cooler is connected with a hot end medium inlet of the heat regenerator. A hot-end medium outlet of the heat regenerator is divided into two paths after passing through the drying filter, one path is connected with a refrigerant inlet of the evaporator through the main liquid supply pipe group, a refrigerant outlet of the evaporator is connected with a cold-end medium inlet of the heat regenerator, and a cold-end medium outlet of the heat regenerator is connected with an air suction port of the screw compressor; the other path is connected with a refrigerant inlet of the oil cooler through an auxiliary liquid supply pipe group, a refrigerant outlet of the oil cooler is connected with the screw compressor, and optimally, the refrigerant outlet of the oil cooler is connected with an oil cooling air supplementing opening formed in a compression cavity middle pressure stage area of the screw compressor. The unit refrigeration efficiency can be effectively improved, it is ensured that the unit operates more stably, mine heat damage is reduced, and energy conservation and emission reduction are better achieved.

Description

Technical Field

[0001] The utility model relates to an explosion-proof refrigeration device for mine cooling, specifically an energy efficiency improved mine explosion-proof refrigeration unit. Background Technique

[0002] With the continuous increase of the mine mining depth, the problem of mine geothermal heat becomes more and more prominent. Coupled with the heat generated during the operation of electromechanical equipment, the temperature inside the mine rises sharply. Such a high-temperature and high-humidity environment seriously affects the work efficiency and physical health of miners. As the body temperature of miners rises, especially when the ambient temperature exceeds the human tolerance limit, the risk of heat stroke will also increase significantly. Miners may experience symptoms such as headache, dizziness, tinnitus, nausea, vomiting, and even syncope. In extreme cases, serious symptoms such as heat stroke, heat cramps, and heat exhaustion may occur, endangering life safety. Moreover, the electromechanical equipment inside the mine has its applicable temperature and humidity ranges. When the ambient temperature and humidity exceed their limits, it will make it difficult for the electromechanical equipment to dissipate heat, resulting in overheating, damage or failure of the equipment, thus affecting the work efficiency and service life of the equipment. This not only accelerates the aging of electromechanical equipment, increases the equipment failure rate, increases the maintenance cost, but also may affect the normal production operation of the mine. It can be seen that mine heat harm brings serious hazards to miners' health, labor efficiency, production safety, and the normal operation of equipment. Therefore, effective measures must be taken to control the mine heat harm problem to ensure the physical and mental health of miners and production safety.

[0003] Existing mine refrigeration and cooling facilities mostly adopt piston or screw compression explosion-proof refrigeration units. However, due to the influence of harsh environments such as too high temperature, small and enclosed space, and poor air permeability in the deep mine, many explosion-proof refrigeration units have problems such as poor refrigeration effect, unstable operation of the unit, and low energy efficiency. In severe cases, there may even be an alarm and shutdown phenomenon. How to make the unit operate more stably, improve the operating energy efficiency of the unit, and better save energy and reduce emissions is an important topic faced by current mine refrigeration equipment. Summary of the Invention

[0004] The purpose of the utility model is to provide an energy efficiency improved mine explosion-proof refrigeration unit, which can effectively improve the refrigeration efficiency of the unit, ensure more stable operation of the unit, thereby reducing mine heat harm and better achieving energy conservation and emission reduction.

[0005] To achieve the above object, the energy efficiency improved mine explosion-proof refrigeration unit designed by the utility model includes a screw compressor, an oil separator, an oil cooler, a condenser and an evaporator connected by pipelines and valves. The screw compressor is driven by an explosion-proof high-voltage three-phase asynchronous motor through a coupling. The exhaust port of the screw compressor is connected to the mixed refrigerant inlet of the oil separator, and the refrigerant outlet of the oil separator is connected to the refrigerant input end of the condenser. The oil outlet of the oil separator is sequentially connected to the hot oil inlet of the oil cooler through an oil coarse filter and an oil pump. The oil pump is driven by an explosion-proof three-phase asynchronous motor. The cold oil outlet of the oil cooler is connected to the shaft seals, bearings and rotor cavity oil return ports of the screw compressor through an oil fine filter.

[0006] What is special is that it further includes a regenerator. The refrigerant output end of the condenser is connected to the hot end medium inlet of the regenerator. The hot end medium outlet of the regenerator is divided into two paths after passing through a drying filter: one path is connected to the refrigerant inlet of the evaporator through the main liquid supply pipe group. The refrigerant outlet of the evaporator is connected to the cold end medium inlet of the regenerator, and the cold end medium outlet of the regenerator is connected to the suction port of the screw compressor. The other path is connected to the refrigerant inlet of the oil cooler through the auxiliary liquid supply pipe group, and the refrigerant outlet of the oil cooler is connected to the screw compressor.

[0007] Further, an oil-cooled gas replenishment port is provided in the compression chamber of the screw compressor, and the refrigerant outlet of the oil cooler is connected to the oil-cooled gas replenishment port. Adding an oil-cooled gas replenishment port to the screw compressor can achieve a gas replenishment effect similar to that of an economizer, reduce the waste of the refrigeration capacity of the refrigerant, and effectively improve the working energy efficiency of the compression unit.

[0008] Even further, the opening position of the oil-cooled gas replenishment port is in the intermediate pressure stage area of the compression chamber of the screw compressor. In this way, the refrigeration capacity can be utilized to the maximum extent, which is more conducive to achieving energy conservation and emission reduction.

[0009] Still further, both the regenerator and the oil cooler are plate heat exchangers. Adopting the plate heat exchanger structure, the refrigerant or lubricating oil realizes heat exchange inside the heat exchanger, which can make the overall structure of the unit compact, occupy a small area, and facilitate the transportation and use of the unit in the limited positions of the mine.

[0010] Also further, both the main liquid supply pipe group and the auxiliary liquid supply pipe group are composed of a globe valve, an electric control valve and a throttle valve connected in series. Combining the electric control valve with the throttle valve can facilitate remote control of the opening and closing and the opening degree of the electric control valve, and cooperate with the corresponding throttle valve to improve the throttling effect.

[0011] The advantages of the present utility model are as follows: A regenerator is added to the refrigerant circulation system of the mine explosion-proof refrigeration unit. Its function is to subcool the refrigerant working medium supplied at the hot end of the unit. On the one hand, it can reduce the gas flashing of the main liquid supply and oil cooler liquid supply of the unit, enhance the heat exchange effect of the evaporator, and ensure the heat exchange effect of the oil cooler, thereby ensuring the stability of the lubricating oil temperature of the unit. On the other hand, it can effectively improve the refrigerating capacity and working energy efficiency of the mine explosion-proof refrigeration unit. At the same time, the regenerator superheats the refrigerant working medium returned from the evaporator at the cold end of the unit to the suction port of the compressor, which can reduce the possibility of liquid carry-over of the mine explosion-proof refrigeration unit, ensure more stable operation of the unit, and is also more conducive to controlling the temperature of the underground operation site, reducing the mine heat hazard, and ensuring the health of miners. Description of the Drawings

[0012] Figure 1 It is a schematic connection structure diagram of the energy efficiency improved mine explosion-proof refrigeration unit of the present utility model.

[0013] The reference numerals of each component in the figure are as follows: screw compressor 1; flameproof high-voltage three-phase asynchronous motor 2; oil separator 3; regenerator 4; oil fine filter 5; oil cooler 6, oil pump 7; flameproof three-phase asynchronous motor 8; oil coarse filter 9; auxiliary liquid supply pipe group 10; main liquid supply pipe group 11; evaporator 12; dry filter 13; condenser 14. Detailed Embodiments

[0014] The following further describes the present utility model in detail with reference to the drawings and specific embodiments, but this embodiment should not be construed as a limitation to the present utility model.

[0015] As Figure 1 The energy efficiency improved mine explosion-proof refrigeration unit shown has a screw compressor 1, an oil separator 3, an oil cooler 6, a condenser 14, an evaporator 12, and a regenerator 4 connected through various pipelines and valves. The screw compressor 1 is connected to the flameproof high-voltage three-phase asynchronous motor 2 through a coupling, and is driven by the flameproof high-voltage three-phase asynchronous motor 2 to operate. The exhaust port of the screw compressor 1 is connected to the mixed working medium inlet of the oil separator 3 through a pipeline, and the refrigerant output end of the oil separator 3 is connected to the refrigerant input end of the condenser 14 through a pipeline. The oil outlet of the oil separator 3 is sequentially connected to the hot oil inlet of the oil cooler 6 through the oil coarse filter 9 and the oil pump 7. The oil pump 7 is driven by the flameproof three-phase asynchronous motor 8 to operate. The cold oil outlet of the oil cooler 6 is connected to each shaft seal, bearing, and rotor cavity oil return port of the screw compressor 1 through the oil fine filter 5.

[0016] The refrigerant output end of the condenser 14 is connected to the hot-side medium inlet of the regenerator 4 through a pipeline. The hot-side medium outlet of the regenerator 4 is divided into two paths after passing through the dryer filter 13: one path is connected to the refrigerant inlet of the evaporator 12 through the main liquid supply pipe group 11. The refrigerant outlet of the evaporator 12 is connected to the cold-side medium inlet of the regenerator 4, and the cold-side medium outlet of the regenerator 4 is connected to the suction port of the screw compressor 1; the other path is connected to the refrigerant inlet of the oil cooler 6 through the auxiliary liquid supply pipe group 10, and the refrigerant outlet of the oil cooler 6 is connected to the screw compressor 1.

[0017] More specifically described:

[0018] An oil-cooling gas replenishing port is provided in the compression chamber of the above-mentioned screw compressor 1. The opening position of the oil-cooling gas replenishing port is in the intermediate pressure stage area of the compression chamber of the screw compressor 1. The refrigerant outlet of the oil cooler 6 is connected to the oil-cooling gas replenishing port through a pipeline. Compared with directly connecting the refrigerant outlet of the oil cooler 6 to the suction port of the screw compressor 1, the added oil-cooling gas replenishing port in this embodiment is that the refrigerant working medium is throttled by the auxiliary liquid supply pipe group 10, then exchanges heat and evaporates with the high-temperature lubricating oil in the oil cooler 6, and finally enters the inlet of the screw compressor 1, which can play a role similar to the gas replenishing of an economizer. Cooperating with the regenerator 4, on the one hand, it can increase the suction superheat degree of the evaporator 12, avoid the phenomenon of liquid carry-over of the unit, and ensure the stable operation of the unit; on the other hand, it can subcool the liquid at the refrigerant output end of the condenser 14, ensure the liquid supply and evaporation effect of the evaporator 12, reduce the waste of refrigeration capacity, improve the refrigeration capacity and energy efficiency of the unit, and is more beneficial to energy conservation and emission reduction.

[0019] The above-mentioned regenerator 4 and oil cooler 6 are both plate heat exchangers. Adopting the plate heat exchanger structure, the refrigerant on the cold side and the refrigerant on the hot side in the regenerator 4 exchange heat inside the regenerator 4, and the refrigerant on the cold side and the lubricating oil on the hot side in the oil cooler 6 exchange heat inside the oil cooler 6, which can make the overall structure of the unit compact, save floor space, and facilitate the transportation and operation of the explosion-proof refrigeration unit in the limited space underground.

[0020] The above-mentioned main liquid supply pipe group 11 and auxiliary liquid supply pipe group 10 are both composed of a stop valve, an electric control valve, and a throttle valve connected in series. The two pipe groups adopt the combination of an electric control valve and a throttle valve, and the opening and opening degree of the electric control valve can be remotely controlled, and cooperate with the corresponding throttle valve to improve the throttling effect, timely regulate the refrigerant flow rate of the two pipe groups, prevent liquid carry-over of the unit, and ensure the stable operation of the unit.

[0021] The energy efficiency improved mine explosion-proof refrigeration unit of the utility model uses Freon R22 / R407C as the refrigerant. During operation, the suction port of the screw compressor 1 sucks Freon R22 / R407C from the cold side of the regenerator 4 that comes from the evaporator 12. After compression work, a mixture of high-temperature and high-pressure Freon R22 / R407C gas and high-temperature and high-pressure lubricating oil is formed and enters the oil separator 3 through the exhaust port of the screw compressor 1.

[0022] The high-temperature and high-pressure Freon R22 / R407C gas separated from the oil separator 3 enters the condenser 14 and becomes high-temperature and high-pressure liquid after condensation. This high-temperature and high-pressure liquid passes through the hot side of the regenerator 4 and exchanges heat with the low-temperature and low-pressure Freon R22 / R407C gas from the evaporator 12 to obtain a certain degree of subcooling. Then it passes through the dryer filter 13 and is divided into two paths: one path enters the main liquid supply pipe group 11, undergoes throttling treatment through the main liquid supply pipe group 11, becomes a low-temperature and low-pressure Freon R22 / R407C gas-liquid mixture, then enters the evaporator 12, evaporates into low-temperature and low-pressure Freon R22 / R407C gas, enters the cold side of the regenerator 4, exchanges heat with the high-temperature and high-pressure liquid from the condenser 14 to obtain a certain degree of superheat, and finally returns to the suction port of the screw compressor 1 to complete the refrigeration cycle. The other path enters the auxiliary liquid supply pipe group 10, undergoes throttling treatment through the auxiliary liquid supply pipe group 10, then enters the oil cooler 6, exchanges heat with the high-temperature and high-pressure lubricating oil from the oil separator 3, and finally returns to the oil cooling and gas replenishing port of the screw compressor 1 to complete the refrigeration cycle.

[0023] Meanwhile, the high-temperature and high-pressure lubricating oil separated from the oil separator 3 successively passes through the oil coarse filter 9, oil pump 7, oil cooler 6 and oil fine filter 5, exchanges heat and cools down with the low-temperature and low-pressure Freon R22 / R407C gas-liquid mixture from the auxiliary liquid supply pipe group 10, and then returns to various shaft seals, bearings and rotor cavities of the screw compressor 1 to realize the lubrication of various components of the screw compressor 1.

[0024] To sum up, by means of the technical solution of the utility model, the liquid entering the main liquid supply pipe group and the auxiliary liquid supply pipe group can be subcooled, the generation of flashing gas can be reduced, and the throttling effect of the unit can be ensured; at the same time, the return gas of the evaporator can enter the screw compressor after being in a superheated state, so as to avoid the liquid slugging fault of the compressor caused by the liquid-carrying phenomenon of the unit and ensure the operation stability of the unit. On the other hand, after the refrigerant passes through the throttling of the auxiliary liquid supply pipe group and exchanges heat and evaporates with the high-temperature lubricating oil of the oil cooler and then enters the oil cooling and gas replenishing port of the compressor, the refrigerant can be supplemented at the intermediate pressure stage of the compressor, the refrigerant flow rate and enthalpy difference of the compressor can be increased, the compression efficiency can be improved, and thus the refrigeration capacity of the unit can be enhanced. In this process, although the gas replenishing will increase a certain amount of power consumption, due to the greater increase in refrigeration capacity, the energy efficiency ratio COP of the unit operation is effectively improved.

[0025] The above are only the preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An energy efficiency enhanced explosion-proof mining refrigeration unit, comprising a screw compressor (1), an oil separator (3), an oil cooler (6), a condenser (14) and an evaporator (12) connected by pipelines and valves. The screw compressor (1) is driven by an explosion-proof high-voltage three-phase asynchronous motor (2) through a coupling. The exhaust port of the screw compressor (1) is connected to the mixed working medium inlet of the oil separator (3), and the refrigerant outlet of the oil separator (3) is connected to the refrigerant input end of the condenser (14). The oil outlet of the oil separator (3) is sequentially connected to the hot oil inlet of the oil cooler (6) through an oil coarse filter (9) and an oil pump (7). The oil pump (7) is driven by an explosion-proof three-phase asynchronous motor (8). The cold oil outlet of the oil cooler (6) is connected to the shaft seals, bearings and rotor cavity oil return ports of the screw compressor (1) through an oil fine filter (5). It is characterized in that: It further includes a regenerator (4). The refrigerant output end of the condenser (14) is connected to the hot-end medium inlet of the regenerator (4). The hot-end medium outlet of the regenerator (4) is divided into two paths after passing through a drying filter (13): one path is connected to the refrigerant inlet of the evaporator (12) via a main liquid supply pipe group (11). The refrigerant outlet of the evaporator (12) is connected to the cold-end medium inlet of the regenerator (4), and the cold-end medium outlet of the regenerator (4) is connected to the suction port of the screw compressor (1); the other path is connected to the refrigerant inlet of the oil cooler (6) via an auxiliary liquid supply pipe group (10), and the refrigerant outlet of the oil cooler (6) is connected to the screw compressor (1).

2. The energy efficiency improved explosion-proof mine refrigeration unit according to claim 1, wherein: An oil-cooled gas replenishing port is provided in the compression chamber of the screw compressor (1), and the refrigerant outlet of the oil cooler (6) is connected to the oil-cooled gas replenishing port.

3. The energy efficiency improved explosion-proof mining refrigeration unit according to claim 2, characterized in that: The opening position of the oil-cooled gas replenishing port is in the intermediate pressure stage area of the compression chamber of the screw compressor (1).

4. The energy efficiency improved explosion-proof mine refrigeration unit according to claim 1 or 2 or 3, characterized in that: Both the regenerator (4) and the oil cooler (6) are plate heat exchangers.

5. The energy efficiency enhanced explosion-proof mining refrigeration unit according to claim 1 or 2 or 3, characterized in that: Both the main liquid supply pipe group (11) and the auxiliary liquid supply pipe group (10) are composed of a stop valve, an electric control valve and a throttle valve connected in series.

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