Heat exchanger and air conditioning system with same
Technical Field
The invention relates to the technical field of heat exchange equipment, in particular to an energy-saving and emission-reducing heat exchanger mainly applicable to a mine and an air conditioning system with the heat exchanger.
Background
Traditional cooling tower sets up the fan at the top, and convulsions through the fan make cause that the cooling tower is inside to be the negative pressure environment, and make ambient air get into in the closed cooling tower. After air enters from the bottom of the cooling tower, heat and mass exchange is carried out between the air and spray water dropping from top to bottom at the heat exchange tubes and the filler, and the spray water on the surfaces of the heat exchange tubes and the filler is evaporated and is pumped away together with the air, so that the purpose of cooling the secondary refrigerant in the refrigerant tubes is achieved. However, the traditional cooling tower has the problems of poor spraying uniformity of spraying water and the like, so dry spots are easy to appear in the local area of the heat exchange tube, the heat exchange performance of the closed cooling tower is reduced, and the unit efficiency is influenced. The traditional closed cooling tower generally needs external installation, can produce flying water and great noise, influences the surrounding environment. In addition, the problem that the occupied space is large and the requirements for water and fresh air are large is also solved. If the high-pressure high-efficiency heat exchange local refrigeration equipment is used underground, the underground conveying distance of the mining high-pressure high-efficiency heat exchange local refrigeration equipment is long, the equipment installation space is narrow, the environmental conditions are severe, and strict requirements on air consumption and water consumption are met. Therefore, the traditional closed cooling tower is not suitable for underground working environment of a mine.
Therefore, how to overcome the defects of large occupied space, poor heat exchange performance, large demand for water and fresh air and environmental pollution of the traditional closed cooling tower is a problem to be solved in the industry.
Disclosure of Invention
The invention provides an energy-saving emission-reducing heat exchanger with small occupied space and good heat exchange performance and an air-conditioning system with the heat exchanger, aiming at solving the problems of large occupied space and poor heat exchange performance of the existing closed cooling tower.
The invention provides a heat exchanger which comprises a shell pipe, a heat exchange pipe and a spraying device. The heat exchange tube is partially immersed in the cooling water in the shell tube, and the bottom of the shell tube is provided with an air inlet.
Preferably, the bottom of the shell tube is provided with a water outlet, and the cooling water is communicated with the spraying device through a water pump.
Preferably, the upper part of the shell tube is provided with a water replenishing port.
Preferably, a water level sensor for monitoring the water level of the cooling water is further arranged in the shell pipe.
Preferably, the bottom in the shell pipe is also provided with a liquid equalizing plate.
Preferably, the water outlet is arranged below the plane of the liquid homogenizing plate.
Preferably, the heat exchange tube is integrally arranged on the plane of the liquid homogenizing plate.
Preferably, the heat exchange tubes immersed in the cooling water are 2/4-3/4 of the height of the heat exchange tube bundle.
The invention also provides an air conditioning system which comprises the heat exchanger provided by the invention.
The invention adopts a shell-and-tube heat exchanger structure, compared with the traditional closed cooling tower, a part of heat exchange tubes are completely immersed in water, and a part of heat exchange tubes are covered by spray water which drips from top to bottom. Air with normal temperature and pressure enters from the bottom of the shell-and-tube heat exchanger, absorbs the heat of water outside the heat exchange tube, then is changed into high-temperature high-humidity nearly saturated vapor, and is discharged into the environment through the fan. Because part of the heat exchange tubes of the heat exchanger are completely immersed in water, and the other part of the heat exchange tubes are covered by the spray water dripping from top to bottom, the contact area between the water and the heat exchange tubes is increased, and the heat exchange performance of the heat exchanger is further improved. Therefore, when the same heat exchange benefit of the unit is kept, the size of the heat exchanger can be reduced, and the occupied area is reduced. The closed cooling tower is particularly suitable for high-temperature and high-humidity environments of mines, and under the condition that the heat exchange performance of the traditional closed cooling tower cannot meet the requirements.
Drawings
FIG. 1 is a schematic illustration of a heat exchanger embodiment of the present invention;
fig. 2 is a sectional view taken along a-a in fig. 1.
Detailed Description
The invention is further illustrated by the following examples and figures.
As shown in fig. 1 and 2, the embodiment of the invention provides a novel energy-saving emission-reducing heat exchanger for a mine air conditioning system. The embodiment is a shell and tube heat exchanger, which comprises a shell and tube 1, a heat exchange tube 8 arranged in the shell and tube 1, a spraying device 9 arranged at the inner top of the shell and tube 1, and a fan 3 arranged on the shell and tube 1. The heat exchange tube 9 is partially immersed in cooling water 10 at the middle lower part of the shell tube 1, and the bottom of the shell tube 1 is provided with an air inlet 11. The bottom of the shell tube 1 is also provided with a water outlet 5, and cooling water 10 in the shell tube 1 is communicated with a spraying device 9 through a water pump 6 and a water inlet pipe 2. The height of the heat exchange tubes 8 immersed in the cooling water 10 may be about 2/4-3/4 of the height of the integral heat exchange tube bundle. The height of the cooling water 10 can be adjusted according to the heat exchange requirement.
As shown in fig. 1 and 2, in another embodiment of the present invention, a water level sensor (not shown) is further provided in the casing 1 for monitoring the level of the cooling water 10, and a water replenishing port 4 is provided at the upper part of the casing 1. The bottom in the shell tube 1 is also provided with a liquid equalizing plate 7, and the heat exchange tube 8 is integrally arranged on the plane of the liquid equalizing plate 7, so that the cooling water 10 is conveniently and uniformly distributed, and the input pressure air can be uniformly distributed. The water outlet 5 is arranged below the plane of the liquid equalizing plate 7, so that the water can be recycled conveniently.
The invention also provides an air conditioning system which comprises the heat exchanger.
As shown in fig. 1 and 2, the heat exchanger provided by the invention uses water and air as cooling media, and when the heat exchanger works, high-temperature cooling water circulating in the main machine section of the mine air-conditioning system enters the heat exchange tube 8 of the heat exchanger to exchange heat with low-temperature spray water from top to bottom outside the heat exchange tube 8. Wherein, a part of spray water is deposited at the middle lower part in the shell tube 1, one part of heat exchange tubes 8 in the shell tube 1 are immersed, and the other part of heat exchange tubes 8 which are not immersed are sprayed down from top to bottom by the top of the shell tube 1 to form a film. Pressure air enters through an air inlet 11 at the bottom of the shell and tube 1, enters the cooling water 10 fully soaking the heat exchange tube 8 group through the liquid equalizing plate 7, and carries out heat and mass transfer with deposition water outside the heat exchange tube 8, namely, the pressure air exchanges heat with spray water deposited at the bottom of the shell and tube 1, a water film outside the heat exchange tube 8 which is not soaked and water drops sprayed at the top of the shell and tube 1 in sequence to become saturated wet air.
According to the invention, the cooling water 10 deposited on the lower heat exchange tube 8 of the shell tube 1 is pumped out by the water pump 6 and is conveyed to the spraying device 9 at the top of the shell tube 1 by the water pump 6, so that the spraying water drops from top to bottom, and the problem of inconsistent heat exchange at the upper part and the lower part of the heat exchange tube 8 in the shell tube 1 is solved. The bottom heat exchange tube 8 exchanges heat with the pressure air entering from the bottom of the shell tube 1, the air can absorb the amount of the air deposited in the cooling water 10 at the lower part of the shell 1, the temperature and the humidity are increased, and meanwhile, the spray water from top to bottom is cooled by the air which passes through the cooling water 10 at the bottom of the shell tube 1 and rises. Along with the rising of the air, the air gradually approaches to saturation, the cooling water 10 with the temperature reduced at the bottom of the heat exchanger in the shell tube 1 is pumped to the top of the shell tube 1 and then drops from top to bottom, and the heat exchange performance of the upper heat exchange tube bundle can be further improved. The top of the heat exchanger is provided with an exhaust port of a fan 3, so that lower pressure is maintained in the heat exchanger. A part of the cooling water 10 is evaporated at a low pressure, mixed with saturated humid air after heat exchange with shower water, and discharged to the atmosphere. The water level sensor arranged on the shell pipe 1 monitors the water level in the heat exchanger in real time, and the water replenishing port 4 is used for replenishing cooling water lost due to evaporation in time so as to maintain the stability of the water level of spray water in the heat exchanger. The heat exchanger can reduce the occupied area of the heat exchanger and the heat exchanger under the condition of realizing the same cooling capacity by using the heat exchanger, thereby realizing the cost reduction.
The heat exchanger adopts a shell-and-tube heat exchanger structure, and a part of spray water is deposited at the middle lower part of a shell tube 1 and immerses a middle-lower heat exchange tube 8. The upper part of the heat exchanger is provided with a spraying device 9, spraying water is sprayed from top to bottom, water is distributed on the heat exchange tubes 8 which are not immersed to form a film, and the film exchanges heat with air from the bottom of the heat exchanger. The bottom of the shell tube 1 is provided with a water outlet 5, the water pump 6 pumps cooling water 10 deposited at the bottom of the shell tube 1 to the top of the shell tube 1 continuously, and the cooling water drops in a spray water mode, so that closed circulation of spray water outside the shell tube is realized. The top of the shell tube 1 is provided with a fan 3, so that the spray water in the shell tube 1 is evaporated at low pressure. The heat exchange area is fully utilized by completely soaking the heat exchange tube 8 in the cooling water 10, and the heat exchange effect is improved. The liquid level is monitored by a water level sensor to control circulating spraying water supplement to realize the balance of the water level outside the heat exchange pipe.
The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.