CN204301389U - In conjunction with evaporative cooling and mechanically refrigerated power generating plant cooling tower water-saving system - Google Patents

Abstract

In conjunction with evaporative cooling and mechanically refrigerated power generating plant cooling tower water-saving system disclosed in the utility model, include the enclosed evaporative cooling handpiece Water Chilling Units, mechanical refrigeration system and the cooling stack that are connected by pipe network.The utility model, in conjunction with evaporative cooling and mechanically refrigerated power generating plant cooling tower water-saving system, can reduce evaporative water loss, also can reduce system back pressure, improves steam turbine power generation efficiency, reduces gross coal consumption rate.

Description

Water saving system for power plant cooling tower combining evaporative cooling and mechanical refrigeration

technical field

The utility model belongs to the technical field of cooling equipment, in particular to a water-saving system for a cooling tower of a power plant combined with evaporative cooling and mechanical refrigeration.

Background technique

Due to its own working principle, the cooling tower of a thermal power plant will cause a large amount of water to be evaporated. According to the theoretical design of the cooling tower, the evaporation loss rate is calculated as a percentage of the total circulating water volume, and the circulating volume can be evaporated within three days. It can be seen that the loss of cooling tower water evaporation is very large.

At present, the most common way to reduce the loss of evaporative water is to install a water eliminator inside the cooling tower, but this method can only recover the droplet water, and the saturated water vapor in the tower will also be discharged with the rotation of the fan. This part of the water loss also accounts for a large part of the cooling tower's water consumption. Another way to reduce the loss of cooling tower evaporation water is to use water as a condensing agent in the cooling tower to condense the water vapor into water, thereby reducing the water evaporation loss of the cooling tower, so as to save water in the cooling tower and reduce water consumption. the goal of. The requirement of this method is that the water temperature must be lower than the wet bulb temperature of the cooling tower outlet air to condense the water vapor into water. At present, enterprises have used high-efficiency atomization devices, which can play the role of dust cleaning and cooling, and can reduce water evaporation loss by about 60%.

Based on the above reasons, the chiller unit composed of evaporative cooling chiller and mechanical refrigeration is applied to the water-saving measures of the cooling tower of the power plant. The cold water produced by the combination of evaporative cooling and mechanical refrigeration is sprayed into the tower through the atomizing nozzle, and the water vapor is condensed. After the water is formed, it falls into the sump together; because the chiller combined with evaporative cooling and mechanical refrigeration can produce cold water at about 18°C, which is lower than the wet bulb temperature of the air, thus meeting the conditions for water vapor condensation and reducing the system temperature. Back pressure improves steam turbine power generation efficiency and reduces coal consumption for power generation.

Utility model content

The purpose of this utility model is to provide a cooling tower water-saving system of a power plant combining evaporative cooling and mechanical refrigeration, which can not only effectively solve the problem of cooling tower evaporation water loss, but also reduce the temperature inside the cooling tower.

The technical solution adopted by the utility model is that the cooling tower water-saving system of a power plant combining evaporative cooling and mechanical refrigeration includes a closed evaporative cooling water chiller connected through a pipe network, a mechanical refrigeration system and a natural ventilation cooling tower.

The utility model is also characterized in that:

The closed evaporative cooling water chiller includes an organic unit casing, and the primary air inlet a and the primary air inlet b are respectively arranged on the opposite side walls of the unit casing; the left and right sides of the unit casing are symmetrically arranged with first Tube-type indirect evaporative cooler, second tube-type indirect evaporative cooler, a direct evaporative cooler is arranged between the first tube-type indirect evaporative cooler and the second tube-type indirect evaporative cooler; the first tube-type indirect evaporative cooler A water baffle c and a fan c are sequentially arranged on the top; a water baffle a and a fan a are sequentially arranged above the second tubular indirect evaporative cooler; a water baffle b and a fan b are sequentially arranged above the direct evaporative cooler; Fan c, fan b, and fan a are provided with air outlets on the top wall of the casing of the unit corresponding to fan c.

The first tubular indirect evaporative cooler includes a tubular heat exchanger a, a first spray device is arranged above the tubular heat exchanger a, a water tank a is arranged below the tubular heat exchanger a, and the water tank a communicates with the first spraying device through the first water supply pipe; the first water supply pipe is provided with a first circulating water pump; a first air duct is formed between the tubular heat exchanger a and the water tank a, and the unit corresponding to the first air duct A secondary air inlet a is arranged on the side wall of the housing; the tubular heat exchanger a is composed of a plurality of horizontally arranged heat exchange tubes.

The second tubular indirect evaporative cooler includes a tubular heat exchanger b, a second spray device is arranged above the tubular heat exchanger b, and a water tank c is arranged below the tubular heat exchanger b. c communicates with the second spraying device through the second water supply pipe; the second water supply pipe is provided with a second circulating water pump; a second air duct is formed between the tubular heat exchanger b and the water tank c, and the unit corresponding to the second air duct The side wall of the casing is provided with a secondary air inlet b; the tubular heat exchanger b is composed of a plurality of horizontally arranged heat exchange tubes.

The direct evaporative cooler includes a V-shaped packing, and a cooling coil and a third spray device are arranged above the V-shaped packing in sequence; a water tank b is arranged below the V-shaped packing, and the water tank b is connected to the first water supply pipe through the third water supply pipe. The three spraying devices are connected, and the third water supply pipe is provided with a third circulating water pump; a third air duct is formed between the V-shaped packing and the water tank b.

The water inlet of the cooling coil is connected to the water outlet at the end of the air conditioner through the first water pipe, and the water outlet of the cooling coil is connected to the water inlet at the end of the air conditioner through the second water pipe; the second water pipe is also connected with the mechanical refrigeration system and the natural ventilation cooling tower respectively. connection; the second water pipe is provided with a valve a.

The mechanical refrigeration system includes a compressor, which is sequentially connected to an evaporator, a throttle valve and a condenser to form a closed circuit, and the evaporator is connected to the second water pipe through a third water pipe.

The third water pipe is provided with a valve b.

The natural ventilation cooling tower includes a tower body, the top wall of the tower body is provided with an exhaust outlet; the tower body is provided with packing, and the top of the packing is successively provided with a water distribution device, a water collector and multiple atomizing nozzles, and multiple mist The spray nozzle is connected to the second water pipe through the fourth water pipe; there is a sump below the packing, and the cold water outlet pipe is connected to the sump, and an air flow channel is formed between the packing and the sump, and the corresponding air flow channel is set on the side wall of the tower body. There are air inlets.

The water distribution device is composed of a hot water inlet pipe and a plurality of nozzles arranged on the hot water inlet pipe, and the plurality of nozzles are evenly arranged; the fourth water pipe is provided with a water pump.

The beneficial effects of the utility model are:

1. The cooling tower water-saving system of the power plant of the present utility model applies the chiller combined with evaporative cooling and mechanical refrigeration to the water-saving measures of the cooling tower. , to reduce the evaporation water loss of the cooling tower; on the other hand, it can also reduce the water temperature of the cooling tower, so that the vacuum degree of the steam turbine can be improved, the back pressure can be reduced, the thermal efficiency can be improved, and the coal consumption of power generation can be saved.

2. In the cooling tower water-saving system of the power plant of the present utility model, the outlet water temperature of the evaporative cooling chiller is between the wet bulb temperature and the dew point temperature of the air, while the outlet water temperature of the mechanical refrigeration chiller can reach about 7°C. After mixing in a certain proportion, the water temperature can reach below the dew point temperature of the outlet air of the cooling tower, thus achieving the conditions for water vapor condensation.

3. In the cooling tower water-saving system of the power plant of the present invention, valves are respectively installed on the cold water outlet pipes of evaporative cooling and mechanical refrigeration, and the flow ratio of the two can be adjusted according to the cooling efficiency in the cooling tower, thereby adjusting the spraying water temperature.

4. In the cooling tower water-saving system of the power plant of the present utility model, part of the cold water generated enters the upper part of the cooling tower for spraying; the other part of the cold water enters the air conditioner terminal of the power plant office, and after heat exchange, enters the heat exchange In the coil, circulate.

5. In the cooling tower water-saving system of the power plant of the present invention, the cooling tower adopts a hyperbolic natural ventilation cooling tower, and no fan is used, which reduces investment.

Description of drawings

Fig. 1 is a structural schematic diagram of a cooling tower water-saving system of a power plant combining evaporative cooling and mechanical refrigeration according to the present invention.

In the figure, 1. Water tank a, 2. Tube heat exchanger a, 3. Water tank b, 4. V-shaped packing, 5. Water tank c, 6. Tube heat exchanger b, 7. Water baffle plate a, 8 .Fan a, 9. Cooling coil, 10. Fan b, 11. Water baffle b, 12. Fan c, 13. Water baffle c, 14. Compressor, 15. Evaporator, 16. Throttle valve, 17. Condenser, 18. Valve a, 19. Valve b, 20. Atomizing nozzle, 21. Natural draft cooling tower, 22. Pool, 23. Air conditioner terminal, 24. First water supply pipe, 25. First circulation Water pump, 26. secondary air inlet a, 27. second water supply pipe, 28. second circulating water pump, 29. secondary air inlet b, 30. third water supply pipe, 31. third circulating water pump, 32. Packing, 33. Hot water inlet pipe, 34. Cold water outlet pipe, 35. Water eliminator, 36. Primary air inlet a, 37. Primary air inlet b, G1. First water pipe, G2. Second water pipe, G3 . The third water pipe, G4. The fourth water pipe.

Detailed ways

The utility model will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

The utility model combines evaporative cooling and mechanical refrigeration power plant cooling tower water-saving system. Its structure is shown in Figure 1, including a closed evaporative cooling water chiller connected through a pipe network, a mechanical refrigeration system and a natural ventilation cooling tower 21.

The closed evaporative cooling chiller, as shown in Figure 1, includes an organic unit shell, and the primary air inlet a36 and the primary air inlet b37 are respectively arranged on the opposite side walls of the unit shell; the left and right sides of the unit shell are symmetrical A first tube-type indirect evaporative cooler and a second tube-type indirect evaporative cooler with the same structure are provided, and a direct evaporative cooler is arranged between the first tube-type indirect evaporative cooler and the second tube-type indirect evaporative cooler; A water baffle c13 and a fan c12 are sequentially arranged above the first tubular indirect evaporative cooler, a water baffle a7 and a fan a8 are arranged sequentially above the second tubular indirect evaporative cooler, and a baffle is arranged sequentially above the direct evaporative cooler The water plate b11, the fan b10, the fan c12, the fan b10 and the fan a8 are all provided with air outlets on the top wall of the casing of the unit.

The first tubular indirect evaporative cooler, as shown in Figure 1, includes a tubular heat exchanger a2, the tubular heat exchanger a2 is composed of a plurality of horizontally arranged heat exchange tubes, and the upper part of the tubular heat exchanger a2 is set There is a first spraying device, a water tank a1 is arranged under the tubular heat exchanger a2, and the water tank a1 communicates with the first spraying device through the first water supply pipe 24; the first water supply pipe 24 is provided with a first circulating water pump 25. A first air duct is formed between the tubular heat exchanger a2 and the water tank a1, and a secondary air inlet a26 is provided on the side wall of the unit housing corresponding to the first air duct.

The second tubular indirect evaporative cooler, as shown in Figure 1, includes a tubular heat exchanger b6, a second spray device is arranged above the tubular heat exchanger b6, and a second spray device is arranged below the tubular heat exchanger b6. The water tank c5 communicates with the second spraying device through the second water supply pipe 27; the second water supply pipe 27 is provided with a second circulating water pump 28. A second air passage is formed between the tubular heat exchanger b6 and the water tank c5, and a secondary air inlet b29 is provided on the side wall of the unit housing corresponding to the second air passage.

The tubular heat exchanger a2 and the tubular heat exchanger b6 are composed of a plurality of horizontally arranged heat exchange tubes.

The direct evaporative cooler includes a V-shaped packing 4, a cooling coil 9 and a third spray device are arranged above the V-shaped packing 4, and a water tank b3 is arranged below the V-shaped packing 4, and the water tank b3 passes through the third water supply pipe 30 communicates with the third spraying device, the third water supply pipe 30 is provided with a third circulating water pump 31, and the third circulating water pump 31 is located in the water tank b3. A third air duct is formed between the V-shaped packing 4 and the water tank b3.

The water inlet of the cooling coil 9 is connected to the water outlet of the air conditioner end 23 through the first water pipe G1, and the water outlet of the cooling coil 9 is connected to the water inlet of the air conditioner end 23 through the second water pipe G2; the second water pipe G2 is also connected with the mechanical The refrigeration system and the natural draft cooling tower 21 are connected; the second water pipe G2 is provided with a valve a18.

The mechanical refrigeration system includes a compressor 14, the compressor 14 is sequentially connected to the evaporator 15, the throttle valve 16 and the condenser 17 through copper pipes to form a closed circuit, and the evaporator 15 is connected to the second water pipe G2 through the third water pipe G3; The third water pipe G3 is provided with a valve b19.

The natural ventilation cooling tower 21 includes a tower body, the top wall of the tower body is provided with an exhaust outlet, the tower body is provided with a packing 32, and the top of the packing 32 is sequentially provided with a water distribution device, a water eliminator 35 and a plurality of atomizing nozzles 20. The water distribution device is composed of a hot water inlet pipe 33 and a plurality of nozzles arranged on the hot water inlet pipe 33, and the plurality of nozzles are evenly arranged; a plurality of atomizing nozzles 20 are connected to the second water pipe through the fourth water pipe G4, The fourth water pipe G4 is provided with a water pump; the bottom of the filler 32 is provided with a sump 22, and the sump 22 is connected with a cold water outlet pipe 34, and an air flow channel is formed between the filler 32 and the sump 22, and the side of the tower body corresponding to the air flow channel Air inlets are provided on the walls.

The utility model combines evaporative cooling and mechanical refrigeration in a power plant cooling tower water-saving system. A valve a18 is set on the second water pipe G2, and a valve b19 is set on the third water pipe G3. To adjust the flow ratio of the two. If the efficiency of the natural draft cooling tower 21 is low, the dry and wet bulb temperature of the exhaust air outlet air will be higher, so the valve b19 of the cold water outlet of the mechanical refrigeration system can be adjusted to reduce the water output, so that the spray water temperature will be lower. The condensation temperature of water vapor in the cooling tower can be reached.

In the natural ventilation cooling tower, the air enters the tower body from the air inlet, passes through the filler through the air flow channel, flows through the filler in the opposite direction to the hot water flow, and recovers the water droplets in the air through the water eliminator 35. The cold air outside the tower After entering the tower body, after evaporating and contacting the lost heat, the temperature increases, the humidity increases, and the density decreases. Therefore, the air above the water eliminator 35 is often saturated or close to saturated, and the air outside the tower has low temperature, low humidity and high density. Due to the difference in air density inside and outside the tower, there is a pressure difference between the inside and outside of the air inlet, which causes the air outside the tower to flow into the tower continuously, without the need for ventilation machinery to provide power, reducing investment and energy waste. In addition, a plurality of atomizing nozzles 20 are arranged on the upper part of the natural draft cooling tower 21 , so that fine particles and water mist can be combined and fixed, and then fall into the sump 22 together.

The utility model combines the evaporative cooling and mechanical refrigeration cooling tower water-saving system of the power plant, and applies the combined evaporative cooling and mechanical refrigeration chiller to the water-saving measures of the power plant cooling tower. The working process is as follows:

1. Wind system:

After being cooled by the first tubular indirect evaporative cooler and the second tubular indirect evaporative cooler, the outdoor air enters the V-shaped packing 4 in the direct evaporative cooler, and exchanges heat and moisture with the water in the water tank b3. Enter the cooling coil 9, and cool the water in the coil 9 together with the spray water; then pass through the water baffle b11, and then discharge it to the outside through the fan b10.

2. Water system:

After being compressed by the compressor 14, the refrigerant becomes a high-temperature and high-pressure gas, then enters the condenser 17 for heat exchange and cooling with the outside air, and becomes a low-temperature and high-pressure liquid, and then passes through the throttle valve 16 to become a low-temperature and low-pressure liquid , the liquid enters the evaporator 15, exchanges heat with the water in the cooling coil 9, and lowers the water temperature. The flow ratio of the two to achieve the required cold water temperature; part of the generated cold water enters the natural draft cooling tower 21, condenses the water vapor and falls into the sump 22 together, and the other part enters the air-conditioning terminal 23 of the power plant office Return to the cooling coil 9 after heat exchange inside, so the reciprocating cycle.

The utility model combines evaporative cooling and mechanical refrigeration with the power plant cooling tower water-saving system, and applies the combined evaporative cooling and mechanical refrigeration chiller to the water-saving measures of the cooling tower. In the sump 22, the evaporation water loss of the natural ventilation cooling tower 21 can be reduced; on the other hand, the temperature of the natural ventilation cooling tower 21 can also be reduced, so that the vacuum degree of the steam turbine is improved, the back pressure is reduced, the thermal efficiency is improved, and the coal consumption of power generation is saved.

Claims (6)

1. in conjunction with evaporative cooling and mechanically refrigerated power generating plant cooling tower water-saving system, it is characterized in that, include the enclosed evaporative cooling handpiece Water Chilling Units, mechanical refrigeration system and the cooling stack (21) that are connected by pipe network;

Described enclosed evaporative cooling handpiece Water Chilling Units, includes machine unit shell, the two side that described machine unit shell is relative is respectively arranged with First air air inlet a (36), First air air inlet b (37); In described machine unit shell, the left and right sides is symmetrically arranged with the first tube type indirect evaporative cooler, the second tube type indirect evaporative cooler, is provided with direct evaporative cooler between described first tube type indirect evaporative cooler and the second tube type indirect evaporative cooler;

Water fender c (13) and blower fan c (12) is disposed with above described first tube type indirect evaporative cooler; The top of described second tube type indirect evaporative cooler is disposed with water fender a (7) and blower fan a (8); The top of described direct evaporative cooler is disposed with water fender b (11) and blower fan b (10); The machine unit shell roof that described blower fan c (12), blower fan b (10) and blower fan a (8) are corresponding is provided with exhaust outlet;

Described mechanical refrigeration system, include compressor (14), described compressor (14) connects and composes closed-loop path with evaporimeter (15), choke valve (16) and condenser (17) successively, and described evaporimeter (15) is connected with the second water pipe (G2) by the 3rd water pipe (G3); Cooling stack (21), includes tower body, and the roof of described tower body is provided with wind exhausting outlet;

Filler (32) is provided with in described tower body, the top of described filler (32) is disposed with water-distributing device, water collection device (35) and multiple atomizer (20), and multiple atomizer (20) is connected with the second water pipe (G2) by the 4th water pipe (G4); The below of described filler (32) is provided with collecting-tank (22), described collecting-tank (22) is connected with cold water outlet pipe (34), form air flow channel between described filler (32) and collecting-tank (22), the tower body sidewall that described air flow channel is corresponding is provided with air intake; Described water-distributing device is made up of hot water inlet pipe (33) and the multiple nozzles be arranged on hot water inlet pipe (33), and multiple nozzle is in evenly arranging; Described 4th water pipe (G4) is provided with water pump.

2. power generating plant cooling tower water-saving system according to claim 1, it is characterized in that, described first tube type indirect evaporative cooler, include pipe heat exchanger a (2), the top of described pipe heat exchanger a (2) is provided with the first spray equipment, the below of described pipe heat exchanger a (2) is provided with water tank a (1), and described water tank a (1) is communicated with the first spray equipment by the first feed pipe (24);

Described first feed pipe (24) is provided with the first water circulating pump (25);

Form the first air channel between described pipe heat exchanger a (2) and water tank a (1), the machine unit shell sidewall that described first air channel is corresponding is provided with Secondary Air air inlet a (26);

Described pipe heat exchanger a (2) is made up of many horizontally disposed heat exchanger tubes.

3. power generating plant cooling tower water-saving system according to claim 1, it is characterized in that, described second tube type indirect evaporative cooler, include pipe heat exchanger b (6), the top of described pipe heat exchanger b (6) is provided with the second spray equipment, the below of described pipe heat exchanger b (6) is provided with water tank c (5), and described water tank c (5) is communicated with the second spray equipment by the second feed pipe (27);

Described second feed pipe (27) is provided with the second water circulating pump (28);

Form the second air channel between described pipe heat exchanger b (6) and water tank c (5), the machine unit shell sidewall that described second air channel is corresponding is provided with Secondary Air air inlet b (29);

Described pipe heat exchanger b (6) is made up of many horizontally disposed heat exchanger tubes.

4. power generating plant cooling tower water-saving system according to claim 1, it is characterized in that, described direct evaporative cooler, includes V-type filler (4), and the top of described V-type filler (4) is disposed with cooling coil (9) and the 3rd spray equipment; The below of described V-type filler (4) is provided with water tank b (3), described water tank b (3) is communicated with the 3rd spray equipment by the 3rd feed pipe (30), and described 3rd feed pipe (30) is provided with the 3rd water circulating pump (31);

The 3rd air channel is formed between described V-type filler (4) and water tank b (3).

5. power generating plant cooling tower water-saving system according to claim 4, it is characterized in that, the water inlet of described cooling coil (9) is connected with the delivery port of air conditioning terminal (23) by the first water pipe (G1), and the delivery port of described cooling coil (9) is connected with the water inlet of air conditioning terminal (23) by the second water pipe (G2);

Described second water pipe (G2) is also connected with mechanical refrigeration system, cooling stack (21) respectively; Described second water pipe (G2) is provided with valve a (18).

6. power generating plant cooling tower water-saving system according to claim 1, is characterized in that, described 3rd water pipe (G3) is provided with valve b (19).