CN103216255B - Compressed air cold conveying cooling system for mine and cooling method thereof - Google Patents

Abstract

The invention discloses a compressed air cooling system for mines and a cooling method thereof. The three parts of the air supply device are connected sequentially through compressed air pipelines; among them: the natural cooling source subsystem is a water circulation cooling system for compressed air pre-cooling formed by connecting the first-level cooling tower and the first-level cooling spray room through pipelines. Passage; The artificial cold source subsystem is a water circulation cooling passage for artificial cooling of compressed air formed by connecting the secondary cooling tower, the secondary cooling spray room and the refrigerating unit through pipelines in sequence. The present invention pre-cools the compressed air by a natural cooling source, which can greatly reduce the cooling load of the artificial refrigeration equipment, and even do not operate the artificial refrigeration system in winter or transitional seasons, thereby greatly reducing the operating cost of the mine cooling system.

Description

A kind of compressed air cooling system and cooling method for mine

technical field

The invention relates to a mine cooling system, in particular to a compressed air cooling mine cooling system. the

Background technique

With the continuous increase of mine mining depth and the continuous improvement of mining mechanization, mine heat damage has become a decisive factor restricting mine mining depth. For deep mines with a mining depth of more than 800 meters, due to the serious problem of heat damage, it is impossible to fundamentally achieve the control goal of mine heat damage only by adopting non-artificial cooling technical measures such as increasing mine ventilation. Therefore, at present, artificial cooling systems are mostly used to control the heat damage of mines. the

The artificial cooling system of a mine usually consists of a large refrigeration station, large air handling equipment, refrigerant delivery system and related auxiliary equipment. According to the different installation locations of refrigeration units, mine cooling systems can be divided into different types such as refrigeration units installed on the ground, refrigeration units installed underground, and refrigeration units installed on the ground and underground at the same time. the

The mine cooling system in which the refrigeration unit is installed on the ground can be divided into two types: water cooling system and ice cooling system according to the different refrigerants. Since the refrigeration unit and the heat dissipation cooling tower are located on the ground, the cooling efficiency of these two systems is relatively high. But for the water cooling system, due to the static pressure of the water, the static pressure at the bottom of the water pipeline can reach hundreds of kilograms, which is difficult for conventional pipelines and conventional air coolers, and the use of high pressure resistant pipelines and air cooling equipment will The project investment is greatly increased, and the heat transfer effect of the air cooler and the utilization efficiency of cooling capacity are greatly reduced. If the cooling in stages is adopted, although the above-mentioned problems can be solved, since there is a heat transfer temperature difference in each stage of heat transfer, the temperature rise of more than 10°C may occur when the cold water is transported to the bottom air cooler, resulting in most of the cooling loss. During cold delivery. For the ice cooling system, it is necessary to realize various functions such as ground ice production, flake ice, ground and underground ice transportation, underground ice melting, and underground cold water transportation. Slow, and once the system is started, it must run continuously. the

The mine cooling system in which the refrigeration unit is installed underground is divided into two types: underground heat removal system and ground heat removal system according to the installation position of the heat removal cooling tower. The cooling tower of the underground heat removal system is generally set in the return air tunnel. Due to the high temperature and humidity in the return air lane (the relative humidity is mostly above 90%), the cooling capacity is small and the cooling effect is extremely poor, resulting in low cooling efficiency of the refrigeration unit. Although the ground heat removal system solves the problem of heat removal, due to the large static pressure generated by the cooling water at the refrigeration unit, it is necessary to configure a refrigeration unit with a high-pressure condenser with a pressure resistance of up to several hundred kilograms, or set a high-pressure condenser on the cooling water pipeline. Low pressure heat exchanger. Both of these measures greatly reduce the cooling efficiency of the refrigeration unit. the

The mine cooling system in which refrigeration units are installed on the ground and underground at the same time is essentially two-stage refrigeration units connected in series for refrigeration. The two-stage cooling efficiency is low, the cold loss is large, and it is necessary to set up a high-pressure refrigeration unit with a condenser and a high-low pressure heat exchanger. The system is complex and the safety is poor. the

The above three types of mine cooling systems also have a common feature, that is, air coolers are installed at places where cooling is required (mining face, pump room, etc.). Due to the high concentration of coal dust, high humidity, and various corrosive gases in the underground environment, the air cooler has the disadvantages of easy dust formation, easy corrosion, poor heat transfer effect, and high explosion-proof requirements. the

The prior art closest to the present invention is the article "New Mine Centralized Air Conditioning System Using Compressed Air for Cooling" published in "Mine Safety and Environmental Protection" 2004, Volume 31, No. 3. The following technology is disclosed in this article, that is, using compressed air as a cooling medium to directly spray refrigeration to the mining face; the system is mainly composed of refrigeration units, air compressors, air pipelines, intermediate heat exchangers, and air supply. Its main feature is that the air compressor is installed on the ground, and the refrigeration unit, auxiliary equipment, and intermediate heat exchanger are installed in the underground chamber; after the ground air is compressed by the ground air compressor, it is transported to the underground intermediate heat exchange by the gas pipeline. (the low-temperature medium of the intermediate heat exchanger is chilled water from the refrigeration unit) for cooling treatment, and then sent to the mining face through the cooling pipeline, where it is ejected by the air blower on the working face to form a cold air jet; the cold air jet passes through Expansion, entrainment, mixing, etc. will exchange heat with the air flow on the working surface, so as to achieve the purpose of cooling the working surface. The mine cooling system disclosed in this document has the following two problems: ① After the air is compressed by the compressor, the internal energy increases and the temperature rises (usually 30°C to 60°C higher than the ambient temperature). The refrigeration load and operating cost of the mine cooling system have been greatly increased; ②The refrigeration unit and heat removal equipment are installed in the underground chamber, which makes it difficult for the system to discharge heat, and the operating efficiency of the refrigeration unit is reduced, and explosion-proof equipment must be used, which is relatively safe Poor, high investment cost. the

Contents of the invention

The object of the present invention is to overcome the shortcomings of the above-mentioned compressed air mine cooling system, and provide an economical, energy-saving, safe and efficient compressed air cooling system for mines through technical improvement. This cooling system installs both cooling and heat removal equipment on the ground, and adopts a cooling method that combines artificial cooling and natural cold source cooling. the

In order to achieve the above purpose, the system of the present invention is composed of three parts: the air compressor installed on the ground, the natural cold source subsystem, the artificial cold source subsystem, and the compressed air injection air supply device installed on the underground working face through the compressed air delivery pipeline. made; of which:

The natural cold source subsystem is a water circulation cooling path for compressed air pre-cooling formed by connecting the primary cooling tower and the primary cooling spray room through pipelines;

The artificial cold source subsystem is a water circulation cooling path for artificial cooling of compressed air formed by sequentially connecting the secondary cooling tower, the secondary cooling spray room and the refrigerating unit through pipelines. the

Utilize cooling system of the present invention to carry out the method for cooling compressed air for mine as follows:

Step 1: Pre-cooling of compressed air

The compressed air prepared by the air compressor passes through the primary cooling spray room of the natural cold source subsystem, and after heat exchange with the circulating cooling water in the primary cooling spray room, the temperature can be reduced to approximately the balance with the ambient air temperature At the same time, the cooling water flowing out of the first-level cooling tower absorbs most of the heat of the compressed air in the first-level cooling spray chamber, and then flows back to the first-level cooling tower 5 to realize pre-cooling of compressed air. Water circulation cooling. the

Step 2: Artificial cooling of compressed air

The compressed air pre-cooled by the natural cold source subsystem enters the secondary cooling spray room of the artificial cold source subsystem, and exchanges heat with the circulating cooling water in the secondary cooling spray room to further cool down to the required low temperature; at the same time, The circulating chilled water supplied by the evaporator of the refrigeration unit enters the secondary cooling spray chamber to absorb the heat of the compressed air, and then flows back to the refrigeration unit to realize the circulation cooling of the artificial cold source chilled water; the cooling water flowing out of the secondary cooling tower After entering the condenser of the refrigeration unit, absorbing the heat released by the refrigerant, it flows back to the secondary cooling tower to realize the circulating cooling of the cooling water of the refrigeration unit. the

The third step: delivery of low temperature compressed air

The low-temperature compressed air cooled by the artificial cold source subsystem is transported to the underground working face through the compressed air insulation pipe and accessories, and is ejected from the jet air supply port. After expansion, entrainment and mixing, the cooling effect of the working face is realized. the

The advantages of the present invention are:

(1) Pre-cooling the compressed air by using natural cooling sources can greatly reduce the cooling load of artificial refrigeration equipment. In winter or transitional seasons, the artificial refrigeration system may not even be operated (at this time, the secondary cooling spray room is only used for compression Air transmission channel), thus greatly reducing the operating cost of the mine cooling system. the

(2) The artificial cooling equipment for compressed air is all installed on the ground, and non-explosion-proof equipment can be used, with low construction cost and high cooling efficiency. the

(3) The volume of compressed air has large specific heat, strong cooling capacity, and small volume flow rate, so the pipe section is small, the investment is low, and it is convenient for layout and heat preservation. the

Description of drawings

Figure 1 is a schematic diagram of an embodiment of the present invention. the

In the figure: 1- air compressor, 2- primary cooling tower, 3- primary cooling spray room, 4- secondary cooling tower, 5- refrigeration unit, 6- secondary cooling spray room, 7a- primary Cooling compressed air delivery pipeline, 7b-secondary cooling compressed air delivery pipeline, 7c-complete cooling compressed air insulation pipeline, 8-well shaft, 9-underground working face, 10-compressed air injection air supply device, 11-working face air intake Ping Lane. the

Detailed ways

The specific implementation manner thereof will be described below in conjunction with the accompanying drawings and the workflow of the present invention. the

As shown in Figure 1, the system of the present invention consists of an air compressor 1 arranged on the ground, a natural cold source subsystem, an artificial cold source subsystem, and a compressed air injection air supply device 10 arranged on the underground working face through compressed air. The pipelines are connected in sequence; among them:

The natural cold source subsystem is a compressed air pre-cooling water circulation cooling passage formed by connecting the primary cooling tower 2 and the primary cooling spray room 3 through pipelines;

The artificial cold source subsystem is a refrigeration unit cooling water circulation cooling passage formed by sequentially connecting the secondary cooling tower 4, the refrigeration unit 5 and the secondary cooling spray chamber 6 through pipelines. the

It can be seen from the figure that:

The process flow of the natural cold source subsystem is: the cooling water flowing out from the primary cooling tower 2 enters the primary cooling spray chamber 3 through the water supply pipe, circulating water pump and accessories, absorbs most of the heat of the compressed air, and then passes through the return The water pipes and accessories flow back to the primary cooling tower 2 to realize the circulating cooling of the compressed air pre-cooling water. the

The process flow of the artificial cold source subsystem is: the cooling water flowing out from the secondary cooling tower 4 passes through the circulating cooling water supply pipe of the refrigeration unit, the circulating water pump and accessories, enters the condenser of the refrigeration unit 5, and absorbs the heat released by the refrigerant , and then flow back to the secondary cooling tower 4 through the circulating cooling water return pipe and accessories of the refrigeration unit to realize the circulating cooling of the cooling water of the refrigeration unit; the circulating chilled water supplied by the evaporator of the refrigeration unit 5 passes through the secondary cooling spray chamber 6, the water supply pipe, circulating water pump and accessories enter the secondary cooling spray chamber 6, and after further absorbing the heat of the compressed air, they flow back to the refrigeration unit 5 through the return pipe and accessories of the secondary cooling spray chamber 6 to realize artificial cooling. Circulating cooling of source chilled water.

It can also be seen from the figure that when the system of the present invention is working, the ambient air is compressed to a certain pressure by the air compressor 1, and then enters the primary cooling spray chamber 3 for pre-cooling by the primary cooling compressed air delivery pipeline 7a and accessories. The pre-cooled compressed air enters the secondary cooling spray chamber 6 through the secondary cooling compressed air delivery pipeline 7b and accessories, and after further cooling to the required low temperature, it is laid on the ground, the well shaft 8, and the air inlet level of the working face. The completely cooled compressed air insulation pipe 7c and its accessories in the lane 11 are transported to the underground working face 9, sprayed out by the jet air supply device 10, and through expansion, entrainment and mixing, the cooling effect of the working face is realized. the

Claims (1)

1. A method that utilizes the cooling system of compressed air to transport cold to carry out cooling to the mine, it is characterized in that, described cooling system consists of being arranged on the air compressor on the ground, natural cold source subsystem, artificial cold source subsystem and setting The three parts of the compressed air injection air supply device in the underground working face are connected sequentially through compressed air pipelines; among them: The natural cold source subsystem is a water circulation cooling passage for compressed air pre-cooling formed by connecting the primary cooling tower and the primary cooling spray room through pipelines; The artificial cold source subsystem is a water circulation cooling path for artificial cooling of compressed air formed by connecting the secondary cooling tower, the secondary cooling spray room and the refrigerating unit sequentially through pipelines; The method of using the cooling system to cool the mine is as follows: Step 1: Pre-cooling of compressed air The compressed air prepared by the air compressor passes through the primary cooling spray room of the natural cold source subsystem, and after heat exchange with the circulating cooling water in the primary cooling spray room, the temperature can be reduced to approximately the balance of the ambient air temperature. At the same time, the cooling water flowing out of the primary cooling tower absorbs most of the heat of the compressed air in the primary cooling spray chamber, and then flows back to the primary cooling tower 5 to realize the compressed air pre-cooling water circulating cooling; Step 2: Artificial cooling of compressed air The compressed air pre-cooled by the natural cold source subsystem enters the secondary cooling spray room of the artificial cold source subsystem, and exchanges heat with the circulating cooling water in the secondary cooling spray room to further cool down to the required low temperature; at the same time, The circulating chilled water supplied by the evaporator of the refrigeration unit enters the secondary cooling spray chamber to absorb the heat of the compressed air, and then flows back to the refrigeration unit to realize the circulation cooling of the artificial cold source chilled water; the cooling water flowing out of the secondary cooling tower After entering the condenser of the refrigeration unit, absorbing the heat released by the refrigerant, it flows back to the secondary cooling tower to realize the circulating cooling of the cooling water of the refrigeration unit; The third step: delivery of low temperature compressed air The low-temperature compressed air cooled by the artificial cold source subsystem is transported to the underground working face through the compressed air insulation pipe and accessories, and is ejected from the jet air supply port. After expansion, entrainment and mixing, the cooling effect of the working face is realized.