Flue gas condensation and dewatering device and working method

Abstract

The present invention discloses a flue gas condensation and dewatering device and a working method. The evaporative heat exchanger of the present invention uses flue gas and refrigerant for heat exchange, improves heat exchange efficiency, reduces compressor power, and reduces equipment volume, vibration and heat generation. The present invention uses clean flue gas in a double-chamber condenser to pre-cool the original flue gas, which can reduce the inlet flue gas temperature of the evaporative heat exchanger, remove water vapor more thoroughly, and avoid waste caused by temperature rise of the clean flue gas after entering subsequent equipment. The present invention uses a first photoelectric liquid level sensor and a second photoelectric liquid level sensor to respectively collect the condensed water level height in the evaporative heat exchanger and the double-chamber condenser, and cooperates with a micro pump to discharge the condensed water to avoid the formation of a gas passage and cause sampling errors.

Description

Technical Field

[0001] The invention relates to the field of flue gas measurement, and in particular to a flue gas condensation and dehydration device and a working method. Background Art

[0002] In the field of flue gas composition analysis, it is often necessary to remove moisture from flue gas to reduce the interference of water vapor on the accuracy of measurement, and to avoid water vapor entering the flow meter and vacuum pump, causing blockage of the equipment, extending the service life of the equipment, and improving the accuracy of the equipment. The traditional flue gas condensation and water removal device uses a glass condenser filled with antifreeze to allow the antifreeze to exchange heat with the flue gas, and then uses a metal heat exchanger to allow the refrigerant to exchange heat with the antifreeze. Heat exchange oil is also required to increase the contact area between the metal heat exchanger and the glass condenser to improve the heat exchange efficiency. Due to the existence of multiple layers of heat exchange, this solution has a large thermal resistance and low refrigeration efficiency. In order to achieve a higher cooling capacity, the equipment power and heat exchanger size can only be increased, resulting in waste and troublesome use. In addition, a fixed rate drainage method is used for condensed water, which will cause a small amount of gas to escape, resulting in inaccurate flue gas volume. Summary of the invention

[0003] The object of the present invention is to overcome the above-mentioned shortcomings and provide a flue gas condensation and water removal device and a working method, which are compact in size, have high refrigeration efficiency, use a liquid seal to prevent gas escape, and improve measurement accuracy.

[0004] In order to achieve the above-mentioned purpose, a flue gas condensation and water removal device includes a compressor, the outlet of the compressor is connected to a condenser, the outlet of the condenser is connected to the refrigerant inlet of an evaporative heat exchanger, the refrigerant outlet of the evaporative heat exchanger is connected to the inlet of the compressor, the flue gas outlet of the evaporative heat exchanger is connected to the temperature return end inlet of a double-chamber condenser, the temperature return end outlet of the double-chamber condenser is connected to a downstream flue gas device, the flue gas is fed into the pre-cooling end inlet of the double-chamber condenser, and the pre-cooling end outlet of the double-chamber condenser is connected to the flue gas inlet of the evaporative heat exchanger.

[0005] The compressor adopts a variable frequency compressor, and an electronic expansion valve is arranged on the connecting pipeline between the condenser and the evaporative heat exchanger.

[0006] The water outlets of the evaporative heat exchanger and the double-chamber condenser are respectively connected to corresponding check valves, both check valves are connected to micro pumps, and the first photoelectric liquid level sensor and the second photoelectric liquid level sensor are respectively arranged at the water outlets of the evaporative heat exchanger and the double-chamber condenser.

[0007] The evaporative heat exchanger adopts an inner and outer outer tube type heat exchanger, the inner tube of the evaporative heat exchanger is the refrigerant circuit, and the outer tube of the evaporative heat exchanger is the flue gas circuit.

[0008] The outer tube wall of the inner tube of the evaporative heat exchanger adopts a concave-convex pattern structure; the bottom of the outer tube of the evaporative heat exchanger is provided with a water outlet hole, and the water outlet hole is connected to a check valve.

[0009] The double chamber condenser is filled with coolant.

[0010] A temperature probe is provided at the flue gas outlet of the evaporative heat exchanger.

[0011] A working method of a flue gas condensation and water removal device comprises the following steps:

[0012] Start the compressor, the low-pressure gaseous refrigerant becomes high-temperature and high-pressure liquid refrigerant after passing through the compressor, the high-temperature and high-pressure liquid refrigerant becomes high-pressure liquid refrigerant after passing through the condenser, the high-pressure liquid refrigerant becomes low-pressure liquid refrigerant after adjusting the flow rate, and then enters the evaporative heat exchanger;

[0013] When the flue gas sampling starts, the flue gas enters the flue gas cavity of the double-chamber condenser, exchanges heat with the heat exchange medium in the double-chamber condenser, and then enters the evaporative heat exchanger to exchange heat with the low-pressure liquid refrigerant. The flue gas is cooled and becomes low-temperature flue gas. The water vapor in the flue gas forms condensed water in the evaporative heat exchanger and gathers at the bottom of the evaporative heat exchanger. The low-pressure liquid refrigerant becomes a low-temperature and low-pressure gaseous refrigerant and returns to the compressor.

[0014] The low-temperature flue gas enters the clean flue gas cavity of the double-chamber condenser, exchanges heat with the heat exchange medium of the double-chamber condenser, is converted into normal-temperature flue gas, and then enters the downstream equipment.

[0015] The high-pressure liquid refrigerant is adjusted to a low-pressure liquid refrigerant through an electronic expansion valve.

[0016] After the condensed water gathers at the bottom of the evaporative heat exchanger and reaches the height of the first photoelectric liquid level sensor, the first photoelectric liquid level sensor sends a signal to start the micro pump to continuously discharge the condensed water until the signal disappears and then stops after a preset time.

[0017] The condensed water in the double-chamber condenser collects the liquid level through the second photoelectric liquid level sensor. When the liquid level reaches the height of the second photoelectric liquid level sensor, the second photoelectric liquid level sensor sends a signal to start the micro pump to continuously discharge the condensed water until the signal disappears and then stops after the preset time.

[0018] Compared with the prior art, the evaporative heat exchanger of the present invention uses flue gas and refrigerant for heat exchange, which improves heat exchange efficiency, reduces compressor power, and reduces equipment size, vibration and heat generation; the present invention uses clean flue gas in the double-chamber condenser to pre-cool the original flue gas, which can reduce the inlet flue gas temperature of the evaporative heat exchanger, more thoroughly remove water vapor, and avoid waste caused by temperature rise of the clean flue gas after entering subsequent equipment.

[0019] Furthermore, the present invention uses a first photoelectric liquid level sensor and a second photoelectric liquid level sensor to respectively collect the condensed water level heights in the evaporative heat exchanger and the double-chamber condenser, and cooperates with a micro pump to discharge the condensed water to avoid the formation of a gas passage and cause sampling errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention;

[0021] Figure 2 Schematic diagram of the internal structure of the evaporative heat exchanger in the present invention;

[0022] Among them, 1. compressor, 2. condenser, 3. electronic expansion valve, 4. evaporative heat exchanger, 5. double-chamber condenser, 6. temperature probe, 7. first photoelectric liquid level sensor, 8. second photoelectric liquid level sensor, 9. check valve, 10. micro pump. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] See also Figure 1 A flue gas condensation and dehydration device comprises a compressor 1, the outlet of the compressor 1 is connected to a condenser 2, the outlet of the condenser 2 is connected to a refrigerant inlet of an evaporative heat exchanger 4, the refrigerant outlet of the evaporative heat exchanger 4 is connected to the inlet of the compressor 1, the flue gas outlet of the evaporative heat exchanger 4 is connected to the return temperature end inlet of a double-chamber condenser 5, a temperature probe 6 is arranged at the flue gas outlet of the evaporative heat exchanger 4, the temperature probe 6 is used to measure the lowest flue gas temperature at the flue gas outlet, and ensure that the temperature reaches the temperature for condensation and dehydration. The return temperature end outlet of the double-chamber condenser 5 is connected to the downstream flue gas equipment, the precooling end inlet of the double-chamber condenser 5 is fed with flue gas, and the precooling end outlet of the double-chamber condenser 5 is connected to the flue gas inlet of the evaporative heat exchanger 4. The double-chamber condenser 5 is filled with coolant. The water outlets of the evaporative heat exchanger 4 and the double-chamber condenser 5 are respectively connected to corresponding check valves 9, and both check valves 9 are connected to a micro pump 10. The water outlets of the evaporative heat exchanger 4 and the double-chamber condenser 5 are respectively provided with a first photoelectric liquid level sensor 7 and a second photoelectric liquid level sensor 8.

[0025] The compressor 1 is a variable frequency compressor, and an electronic expansion valve 3 is provided on the connecting pipeline between the condenser 2 and the evaporative heat exchanger 4. If the compressor 1 is a fixed frequency compressor, the electronic expansion valve 3 is not required.

[0026] See also Figure 2 The evaporative heat exchanger 4 adopts an inner and outer outer tube heat exchanger, the inner tube of the evaporative heat exchanger 4 is a refrigerant circuit, and the outer tube of the evaporative heat exchanger 4 is a flue gas circuit. The outer tube wall of the inner tube of the evaporative heat exchanger 4 adopts a concave-convex pattern structure; the bottom of the outer tube of the evaporative heat exchanger 4 is provided with a water outlet, and the water outlet is connected to a check valve 9.

[0027] Preferably, the micro pump 10 is a small pump with high precision and low flow rate, such as a peristaltic pump or a pulse pump.

[0028] A working method of a flue gas condensation and water removal device comprises the following steps:

[0029] Step 1: start the compressor 1, the low-pressure gaseous refrigerant becomes a high-temperature and high-pressure liquid refrigerant after passing through the compressor 1, and the high-temperature and high-pressure liquid refrigerant becomes a high-pressure liquid refrigerant after passing through the condenser 2;

[0030] Step 2: The high-pressure liquid refrigerant is adjusted to a low-pressure liquid refrigerant through the electronic expansion valve 3, and then enters the evaporative heat exchanger 4;

[0031] Step 3: When the flue gas sampling starts, the flue gas enters the flue gas cavity of the double-chamber condenser 5, exchanges heat with the heat exchange medium in the double-chamber condenser 5, and then enters the evaporative heat exchanger 4 to exchange heat with the low-pressure liquid refrigerant. The flue gas is cooled and becomes low-temperature flue gas. The water vapor in the flue gas forms condensed water in the evaporative heat exchanger 4 and gathers at the bottom of the evaporative heat exchanger 4. The low-pressure liquid refrigerant becomes a low-temperature and low-pressure gaseous refrigerant and returns to the compressor 1.

[0032] Step 4: The low-temperature flue gas enters the clean flue gas cavity of the double-chamber condenser 5, exchanges heat with the heat exchange medium of the double-chamber condenser 5, is converted into room-temperature flue gas, and then enters the downstream equipment.

[0033] Step 5: After the condensed water gathers at the bottom of the evaporative heat exchanger 4 and reaches the height of the first photoelectric liquid level sensor 7, the first photoelectric liquid level sensor 7 sends a signal, and the micro pump 10 is started to continuously discharge the condensed water until the signal disappears and then stops after the preset time.

[0034] The condensed water in the double-chamber condenser 5 collects the liquid level through the second photoelectric liquid level sensor 8. When the liquid level reaches the height of the second photoelectric liquid level sensor 8, the second photoelectric liquid level sensor 8 sends a signal to start the micro pump 10 to continuously discharge the condensed water until the signal disappears and then continues to run for a preset time and then stops.

Claims

1. A flue gas condensation and dehydration device, characterized in that: The invention comprises a compressor (1), wherein the outlet of the compressor (1) is connected to a condenser (2), the outlet of the condenser (2) is connected to a refrigerant inlet of an evaporative heat exchanger (4), the refrigerant outlet of the evaporative heat exchanger (4) is connected to an inlet of the compressor (1), the flue gas outlet of the evaporative heat exchanger (4) is connected to a temperature return end inlet of a double-chamber condenser (5), the temperature return end outlet of the double-chamber condenser (5) is connected to a downstream flue gas device, the precooling end inlet of the double-chamber condenser (5) is fed with flue gas, and the precooling end outlet of the double-chamber condenser (5) is connected to the flue gas inlet of the evaporative heat exchanger (4); The water outlets of the evaporative heat exchanger (4) and the double-chamber condenser (5) are respectively connected to corresponding check valves (9), and both check valves (9) are connected to a micro pump (10). The water outlets of the evaporative heat exchanger (4) and the double-chamber condenser (5) are respectively provided with a first photoelectric liquid level sensor (7) and a second photoelectric liquid level sensor (8); The double-chamber condenser (5) is filled with coolant; A temperature probe (6) is provided at the flue gas outlet of the evaporative heat exchanger (4).

2. The flue gas condensation and water removal device according to claim 1, characterized in that: The compressor (1) is a variable frequency compressor, and an electronic expansion valve (3) is provided on the connecting pipeline between the condenser (2) and the evaporative heat exchanger (4).

3. The flue gas condensation and water removal device according to claim 1, characterized in that: The evaporative heat exchanger (4) adopts an inner and outer outer tube type heat exchanger, the inner tube of the evaporative heat exchanger (4) is a refrigerant circuit, and the outer tube of the evaporative heat exchanger (4) is a flue gas circuit.

4. The flue gas condensation and water removal device according to claim 3, characterized in that: The outer tube wall of the inner tube of the evaporative heat exchanger (4) adopts a concave-convex pattern structure; the bottom of the outer tube of the evaporative heat exchanger (4) is provided with a water outlet hole, and the water outlet hole is connected to the check valve (9).

5. The working method of the flue gas condensation and water removal device according to claim 1, characterized in that: The following steps are involved: The compressor (1) is started, and the low-pressure gaseous refrigerant is converted into a high-temperature and high-pressure liquid refrigerant after passing through the compressor (1). The high-temperature and high-pressure liquid refrigerant is converted into a high-pressure liquid refrigerant after passing through the condenser (2). The high-pressure liquid refrigerant is converted into a low-pressure liquid refrigerant after adjusting the flow rate, and then enters the evaporative heat exchanger (4); When the flue gas sampling starts, the flue gas enters the flue gas cavity of the double-chamber condenser (5), exchanges heat with the heat exchange medium in the double-chamber condenser (5), and then enters the evaporative heat exchanger (4) to exchange heat with the low-pressure liquid refrigerant. The flue gas is cooled and becomes low-temperature flue gas. Water vapor in the flue gas forms condensed water in the evaporative heat exchanger (4) and gathers at the bottom of the evaporative heat exchanger (4). The low-pressure liquid refrigerant is converted into low-temperature and low-pressure gaseous refrigerant and then returns to the compressor (1). The low-temperature flue gas enters the clean flue gas cavity of the double-cavity condenser (5), exchanges heat with the heat exchange medium of the double-cavity condenser (5), is converted into flue gas at normal temperature, and then enters the downstream equipment.

6. The working method of a flue gas condensation and water removal device according to claim 5, characterized in that: The high-pressure liquid refrigerant is adjusted to a low-pressure liquid refrigerant through the electronic expansion valve (3).

7. The working method of a flue gas condensation and water removal device according to claim 5, characterized in that: After the condensed water gathers at the bottom of the evaporative heat exchanger (4), when it reaches the height of the first photoelectric liquid level sensor (7), the first photoelectric liquid level sensor (7) sends a signal, starts the micro pump (10) to continuously discharge the condensed water until the signal disappears and then stops after a preset time.

8. The working method of a flue gas condensation and water removal device according to claim 5, characterized in that: The liquid level of the condensed water in the double-chamber condenser (5) is collected by the second photoelectric liquid level sensor (8); when the liquid level reaches the height of the second photoelectric liquid level sensor (8), the second photoelectric liquid level sensor (8) sends a signal, starts the micro pump (10) to continuously discharge the condensed water until the signal disappears and then stops after a preset time.

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