Polyester turbine power generation system for high-speed axial steam exhaust

Abstract

The utility model discloses a polyester high-speed axial steam exhaust turbine power generation system which comprises a polyester axial steam exhaust turbine power generation system, a refrigeration system, a cooling water system and a vacuum system. The polyester axial steam exhaust turbine power generation system comprises a first steam-water separator, a high-speed axial steam exhaust turbine, a synchronous generator, a condenser, a condensate pump and a condensate tank. Polyester steam enters a high-speed axial steam exhaust turbine through a steam-water separator for acting, dead steam is formed after acting and enters a condenser for heat exchange, condensate is formed after heat exchange and enters a hot water well of the condenser, and the condensate enters a condensate tank through a condensate pump for recycling; compared with the prior art, by arranging the chilled water system and the rear cooler, acetaldehyde in steam can be condensed into esterified water as much as possible, the influence of acetaldehyde non-condensable gas in the esterified steam on vacuum is reduced, the vacuum degree of the system is greatly improved, and the power generation load of the system is optimized.

Description

Technical Field

[0001] This utility model relates to the field of steam waste heat utilization equipment, specifically to a high-speed axial exhaust turbine power generation system for polyester. Background Technology

[0002] In the current polyester (PET) production process in the chemical fiber and dyeing industry, the heat from the esterification steam at the top of the ethylene glycol separation tower, which originally required cooling, is used to produce low-temperature water for polyester process cooling and spinning workshop cooling during periods of high ambient temperature in summer. However, due to seasonal changes, the produced low-temperature water cannot be consumed on-site during spring, autumn, and winter, posing a challenge for low-temperature water treatment. Some companies directly cool and recover the esterification condensate using methods such as air cooling and water cooling, resulting in a significant loss of the heat energy in the esterification steam and an increase in the company's electricity costs.

[0003] The comprehensive utilization of polyester vapor produced by polyester reactors has become a key focus of energy conservation and consumption reduction in the chemical fiber industry. Various methods, such as organic Rankine cycle power generation and lithium bromide refrigeration, are used to utilize waste heat. However, the utilization effect of waste heat is often poor, and the maximum utilization of polyester vapor is not achieved. This leads to various problems such as oil leakage, leakage of organic working fluid, and low power generation efficiency in organic Rankine cycle power generation. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing polyester steam recovery and utilization devices, which have problems such as insufficient utilization of waste heat and easy to cause oil leakage, leakage of organic working fluid, and low power generation efficiency in organic Rankine cycle power generation. To address these shortcomings, a turbine power generation system with high-speed axial exhaust of polyester is proposed.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A high-speed axial exhaust turbine power generation system for polyester includes a polyester axial exhaust turbine power generation system, a refrigeration system, a cooling water system, and a vacuum system; the polyester axial exhaust turbine power generation system includes a first steam-water separator, a high-speed axial exhaust turbine, a synchronous generator, a condenser, a condensate pump, and a condensate tank.

[0007] Among them, polyester vapor enters the high-speed axial exhaust turbine through the steam-water separator to do work. After doing work, it forms exhaust steam that enters the condenser for heat exchange. After heat exchange, it forms condensate that enters the hot water well of the condenser and is then pumped into the condensate tank for recovery.

[0008] The cooling water system generates cooling water. Part of the cooling water enters the condenser to exchange heat with the exhaust steam. After heat exchange, the water flows back to the cooling water system for cooling, forming a cooling water circulation. The other part of the cooling water enters the refrigeration system to form chilled water, which is then sent to the vacuum system and the polyester axial exhaust turbine power generation system. After heat exchange, it flows back to the refrigeration system, forming a chilled water circulation.

[0009] The polyester axial exhaust turbine power generation system generates non-condensable gas, which is extracted by a vacuum system and discharged to the exhaust gas treatment system.

[0010] As a further preferred embodiment of this utility model, a main steam speed-closing valve, a main steam regulating valve, and a spool regulating valve are provided between the first steam-water separator and the high-speed axial exhaust turbine, wherein the main steam regulating valve and the spool regulating valve are connected in parallel.

[0011] As a further preferred embodiment of this invention, the condenser is connected to the aftercooler, and the aftercooler is connected to the liquid seal tank.

[0012] In this process, chilled water enters the aftercooler, and exhaust steam enters the condenser and condenses to produce non-condensable gas. The non-condensable gas enters the aftercooler and exchanges heat with the chilled water in the aftercooler. After the heat exchange, condensate is formed and flows into the liquid seal tank by gravity, and then flows into the condensate tank for recycling.

[0013] As a further preferred embodiment of this utility model, a low-temperature condensate spraying device is provided between the post-cooler and the condenser. The condensate pump is connected to the cooling plate heat exchanger assembly. After the condensate enters the cooling plate heat exchanger assembly for cooling and heat exchange, it enters the post-cooler through the low-temperature condensate spraying device to exchange heat with the non-condensable gas. The cooling plate heat exchanger assembly includes a primary cooling plate heat exchanger and a secondary chilled water plate heat exchanger.

[0014] As a further preferred embodiment of this utility model, the vacuum system includes a second steam-water separator, a water ring vacuum pump, a vacuum pump heat exchanger, and a vacuum regulating valve;

[0015] The second steam-water separator produces demineralized water, which is then used as the working fluid in the water ring vacuum pump.

[0016] Chilled water flows into the vacuum pump plate heat exchanger. After the condensate exchanges heat through the cooling plate heat exchanger assembly, it enters the vacuum pump plate heat exchanger to exchange heat with the chilled water in the vacuum pump plate heat exchanger. Then, it also enters the water ring vacuum pump as working fluid.

[0017] As a further preferred embodiment of this utility model, the refrigeration system includes a chilled water pump, an electric chiller, and a chilled water replenishment tank; one end of the chilled water pump is connected to the electric chiller, and the other end is connected to the chilled water replenishment tank;

[0018] The electric chiller generates chilled water, which is then sent to the vacuum pump plate heat exchanger and aftercooler. After heat exchange, the chilled water flows back to the electric chiller, forming a chilled water circulation.

[0019] As a further preferred embodiment of this utility model, the cooling water system includes several cooling towers, several cooling fans, and several circulating water pumps; the cooling fans are mounted on the cooling towers, one end of the circulating water pump is connected to the outlet of the cooling tower, and the other end is connected to the inlet of the condenser; one cooling fan is configured as a variable frequency cooling fan, and one circulating water pump is configured as a variable frequency circulating water pump.

[0020] In this process, after the cooling tower generates cooling water, the circulating water pump delivers the cooling water to the condenser and the electric chiller. The cooling water undergoes heat exchange in the condenser and then flows back to the cooling tower for cooling, forming a cooling water circuit.

[0021] The chilled water pump pumps the demineralized water from the chilled water makeup tank into the electric chiller. The cooling water enters the electric chiller through the circulating water pump and exchanges heat with the demineralized water in the electric chiller. After the heat exchange, the demineralized water forms chilled water, and the cooling water flows back to the cooling tower.

[0022] As a further preferred embodiment of this utility model, an esterification water regulating valve is provided between the condensate pump and the condensate tank; and a low-temperature condensate regulating valve is provided between the condensate pump and the cooling plate heat exchanger assembly.

[0023] As a further preferred embodiment of this utility model, the condensate pump, chilled water pump, electric chiller, cooling plate heat exchanger and water ring vacuum pump are all configured in two groups, one group is in operation and the other group is on standby.

[0024] As a further preferred embodiment of this invention, the first steam-water separator is configured as a cyclone separator.

[0025] The present invention proposes a high-speed axial exhaust turbine power generation system for polyester, which has the following advantages compared with the prior art:

[0026] 1. This utility model comprehensively considers the correlation between various sub-processes of the polyester high-speed axial exhaust turbine power generation system, which can maximize the energy-saving utilization of the system and enable the reuse of the esterification wastewater generated by the system.

[0027] 2. By setting up a refrigeration system and an aftercooler, the acetaldehyde present in the steam can be condensed into esterified water as much as possible, reducing the impact of non-condensable acetaldehyde gas in the esterified steam on the vacuum, greatly improving the system vacuum level, and optimizing the system power generation load.

[0028] 3. By setting the main steam regulating valve and the spool regulating valve in parallel, the load can be adjusted and the first three spools can be completed by the main steam regulating valve, and the spool regulating valve can complete the fourth spool and reach the rated speed, so as to successfully connect to the grid.

[0029] 4. A low-temperature condensate spraying device is installed before the aftercooler, which can greatly absorb the acetaldehyde that has not been condensed in the condenser and dissolve the acetaldehyde in the low-temperature condensate sprayed from the branch outlet of the secondary refrigeration plate.

[0030] 5. By setting up a primary cooling plate heat exchanger and a secondary refrigeration plate heat exchanger, the esterified water condensate condensed in the condenser is reduced and used as the working fluid of the vacuum pump. This reduces the consumption of demineralized water and meets the rated operating temperature of the vacuum pump working fluid, thereby improving the working performance of the water ring vacuum pump.

[0031] 6. The first steam-water separator adopts a cyclone separator, which automatically separates steam and water, improves steam dryness, and has low pressure loss resistance, and is used to remove water from steam;

[0032] 7. Install one variable frequency cooling fan and one variable frequency circulating water pump, which can be adjusted in winter to save energy and reduce consumption;

[0033] 8. Gravity allows the condensate in the aftercooler to flow into the liquid seal tank, preventing vacuum leakage in the system. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of this utility model.

[0035] The meanings of the reference numerals in the diagram are as follows: 1. First steam-water separator; 2. Main steam speed shut-off valve; 3. Main steam regulating valve; 4. Rotation regulating valve; 5. High-speed axial exhaust turbine; 6. Synchronous generator; 7. Condenser; 8. Aftercooler; 9. Low-temperature condensate spray device; 10. Water ring vacuum pump set; 10.1. Second steam-water separator; 10.2. Water ring vacuum pump; 10.3. Vacuum pump heat exchanger; 10.4. Vacuum regulating valve; 11. Liquid seal tank; 12. First-stage cooling heat exchanger; 13. Second-stage chilled water heat exchanger; 14. Esterification water regulating valve; 15. Low-temperature condensate regulating valve; 16. Condensate pump; 17. Chilled water pump; 18. Electric chiller; 19. Circulating water pump; 20. Cooling tower; 21. Cooling fan; 22. Chilled water makeup tank; 23. Condensate tank. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0037] A high-speed axial exhaust turbine power generation system for polyester includes a polyester axial exhaust turbine power generation system, a refrigeration system, a cooling water system, and a vacuum system. The polyester axial exhaust turbine power generation system includes a first steam-water separator 1, a high-speed axial exhaust turbine 5, a synchronous generator 6, a condenser 7, a condensate pump 16, and a condensate tank 23. A main steam quick-closing valve 2, a main steam regulating valve 3, and a spool regulating valve 4 are arranged between the first steam-water separator 1 and the high-speed axial exhaust turbine 5, and the main steam regulating valve 3 and the spool regulating valve 4 are connected in parallel. The condenser 7 is connected to an aftercooler 8, and a low-temperature condensate spray device 9 is arranged between the aftercooler 8 and the condenser 7. The aftercooler 8 is connected to a liquid seal tank 11, and an esterification water regulating valve 14 is arranged between the condensate pump 16 and the condensate tank 23.

[0038] The first steam-water separator 1 adopts a cyclone separator, which is linked when polyester steam is introduced into the high-speed axial exhaust turbine 5 for warm-up, start-up and grid connection. Before warm-up and the third start-up, the main steam regulating valve 3 participates in controlling the speed of the high-speed axial exhaust turbine 5. When the system is connected to the grid and excited, the start-up regulating valve 4 is used for precise regulation to generate electricity. After power generation, the main steam regulating valve 3 controls the power generation load, and the opening of the start-up regulating valve 4 remains unchanged. After the power generation system tends to be stable, the start-up regulating valve 4 automatically and slowly closes, and the system power generation load is automatically controlled by the main steam regulating valve 3.

[0039] Polyester vapor enters the high-speed axial exhaust turbine 5 through the steam-water separator to do work. After doing work, it forms exhaust steam that enters the condenser 7 for heat exchange. After heat exchange, it forms condensate that enters the hot water well of the condenser 7 and enters the condensate tank 23 for recovery via the condensate pump 16.

[0040] Chilled water enters the aftercooler 8, and the exhaust steam enters the condenser 7 and condenses to produce non-condensable gas. The non-condensable gas enters the aftercooler 8 and exchanges heat with the chilled water in the aftercooler 8. After heat exchange, condensate is formed and flows into the liquid seal tank 11 by gravity, and then flows into the condensate tank 23 for recovery.

[0041] The condensate pump 16 is connected to the cooling plate heat exchanger assembly. After the condensate enters the cooling plate heat exchanger assembly for cooling and heat exchange, it enters the post-cooler 8 through the low-temperature condensate spray device 9 to exchange heat with the non-condensable gas. A low-temperature condensate regulating valve 15 is provided between the condensate pump 16 and the cooling plate heat exchanger assembly. The cooling plate heat exchanger assembly includes a primary cooling plate heat exchanger 12 and a secondary chilled water plate heat exchanger 13.

[0042] The vacuum system includes a second steam-water separator 10.1, a water ring vacuum pump 10.2, a vacuum pump heat exchanger 10.3, and a vacuum regulating valve 10.4. The second steam-water separator 10.1 produces demineralized water, which serves as the working fluid in the water ring vacuum pump 10.2. Chilled water flows into the vacuum pump heat exchanger 10.3; the condensate, after heat exchange through the cooling plate heat exchanger assembly, enters the vacuum pump heat exchanger 10.3 to exchange heat with the chilled water there, and then also enters the water ring vacuum pump 10.2 as working fluid. The water ring vacuum pump 10.2 forms a liquid ring through the working fluid entering the pump body, continuously drawing away non-condensable gases such as acetaldehyde and air from the condenser 7 and aftercooler 8, discharging them to the exhaust gas treatment system. This ensures a good system vacuum and stable power generation; the lower the system vacuum, the higher the power generation and the higher the economic benefits. Exhaust gas treatment is existing technology and is a conventional device in power generation systems; its specific structure and connection relationships are not described in detail in this application.

[0043] The refrigeration system includes a chilled water pump 17, an electric chiller 18, and a chilled water replenishment tank 22. One end of the chilled water pump 17 is connected to the electric chiller 18, and the other end is connected to the chilled water replenishment tank 22. The electric chiller 18 generates chilled water, which is sent to the vacuum pump plate heat exchanger 10.3 and the post-cooler 8. After heat exchange, the chilled water flows back to the electric chiller 18, forming a chilled water circulation.

[0044] The cooling water system includes several cooling towers 20, several cooling fans 21, and several circulating water pumps 19. The cooling fans 21 are installed on the cooling towers 20, and one end of each circulating water pump 19 is connected to the outlet of the cooling tower 20, while the other end is connected to the inlet of the condenser 7. One cooling fan 21 is configured as a variable frequency cooling fan, and one circulating water pump 19 is configured as a variable frequency circulating water pump 19. After the cooling towers 20 generate cooling water, the circulating water pump 19 delivers the cooling water to the condenser 7 and the electric chiller 18. The cooling water undergoes heat exchange in the condenser 7 and then flows back to the cooling towers for further cooling, forming a cooling water loop. The chilled water pump 17 pumps the demineralized water from the chilled water makeup tank 22 into the electric chiller 18. The cooling water enters the electric chiller 18 through the circulating water pump 19 and exchanges heat with the demineralized water in the electric chiller 18. After heat exchange, the temperature of the demineralized water drops to 7-12°C, forming low-temperature chilled water. The cooling water then flows back to the cooling towers 20.

[0045] The condensate pump 16, chilled water pump 17, electric chiller 18, cooling plate heat exchanger and water ring vacuum pump 10.2 are all configured in two sets, one set is in operation and the other set is on standby.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that the above embodiments do not limit this utility model in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of this utility model.

Claims

1. A high speed axial exhaust steam turbine power generation system of a polyester characterized by, The system comprises a polyester axial exhaust turbine power generation system, a refrigeration system, a cooling water system and a vacuum system; the polyester axial exhaust turbine power generation system comprises a first steam-water separator (1), a high-speed axial exhaust turbine (5), a synchronous generator (6), a condenser (7), a condensate pump (16) and a condensate tank (23); The polyester steam enters the high-speed axial exhaust turbine (5) through the steam-water separator to do work, and the steam after work enters the condenser (7) to exchange heat, and the steam after heat exchange enters the hot well of the condenser (7) and then enters the condensate tank (23) through the condensate pump (16) for recycling; The cooling water system generates cooling water, part of which enters the condenser (7) to exchange heat with the steam, and the water after heat exchange flows back to the cooling water system for cooling to form a cooling water circulation; the other part of the cooling water enters the refrigeration system to form refrigeration water, which is sent to the vacuum system and the polyester axial exhaust turbine power generation system, and then flows back to the refrigeration system after heat exchange to form a refrigeration water circulation; The polyester axial exhaust turbine power generation system generates non-condensable gas, which is extracted by the vacuum system and discharged to the tail gas treatment.

2. A high speed axial exhaust steam turbine power generation system of claim 1, wherein The first steam-water separator (1) and the high-speed axial exhaust turbine (5) are connected with a main steam speed valve (2), a main steam regulating valve (3) and a rotation regulating valve (4), and the main steam regulating valve (3) and the rotation regulating valve (4) are connected in parallel.

3. A high speed axial exhaust steam turbine power generation system of claim 1, wherein The condenser (7) is connected with a post-cooler (8), and the post-cooler (8) is connected with a liquid seal tank (11), The refrigeration water enters the post-cooler (8), the steam after condensation in the condenser (7) generates non-condensable gas, the non-condensable gas enters the post-cooler (8) to exchange heat with the refrigeration water in the post-cooler (8), and the condensate after heat exchange flows into the liquid seal tank (11) by gravity and then flows into the condensate tank (23) for recycling.

4. A high speed axial exhaust steam turbine power generation system of claim 3, wherein The post-cooler (8) and the condenser (7) are provided with a low-temperature condensate spraying device (9), the condensate pump (16) is connected with a cooling plate heat exchanger, the condensate after heat exchange in the cooling plate heat exchanger enters the post-cooler (8) through the low-temperature condensate spraying device (9) to exchange heat with the non-condensable gas; the cooling plate heat exchanger comprises a first cooling plate heat exchanger (12) and a second refrigeration water plate heat exchanger (13).

5. A high speed axial exhaust steam turbine power generation system of claim 4, wherein The vacuum system comprises a second steam-water separation tank (10.1), a water ring vacuum pump (10.2), a vacuum pump plate heat exchanger (10.3) and a vacuum regulating valve (10.4); The second steam-water separation tank (10.1) forms desalted water, which enters the water ring vacuum pump (10.2) as working liquid; The refrigeration water flows into the vacuum pump plate heat exchanger (10.3), the condensate after heat exchange in the cooling plate heat exchanger enters the vacuum pump plate heat exchanger (10.3) to exchange heat with the refrigeration water in the vacuum pump plate heat exchanger (10.3), and then enters the water ring vacuum pump (10.2) as working liquid.

6. A high speed axial exhaust steam turbine power generation system of claim 5, wherein The refrigeration system comprises a refrigeration water pump (17), an electric refrigerator (18) and a refrigeration water supplement tank (22); one end of the refrigeration water pump (17) is connected with the electric refrigerator (18), and the other end is connected with the refrigeration water supplement tank (22); Among them, the electric chiller (18) generates chilled water, which is sent to the vacuum pump plate heat exchanger (10.3) and the aftercooler (8). After heat exchange, it flows back to the electric chiller (18) to form a chilled water circulation.

7. A high speed axial exhaust steam turbine power generation system of claim 6, wherein The cooling water system includes several cooling towers (20), several cooling fans (21), and several circulating water pumps (19); the cooling fans (21) are installed on the cooling towers (20), and one end of the circulating water pumps (19) is connected to the outlet of the cooling towers (20), and the other end is connected to the inlet of the condenser (7); one cooling fan (21) is configured as a variable frequency cooling fan, and one circulating water pump (19) is configured as a variable frequency circulating water pump (19). In this process, after the cooling tower (20) generates cooling water, the circulating water pump (19) delivers the cooling water to the condenser (7) and the electric chiller (18). The cooling water undergoes heat exchange in the condenser (7) and then flows back to the cooling tower for cooling, forming a cooling water circuit. The chilled water pump (17) pumps the demineralized water in the chilled water makeup tank (22) into the electric chiller (18). The cooling water enters the electric chiller (18) through the circulating water pump (19) and exchanges heat with the demineralized water in the electric chiller (18). After the heat exchange, the demineralized water forms chilled water, and the cooling water flows back to the cooling tower (20).

8. A high speed axial exhaust steam turbine power generation system of claim 4, wherein An esterification water regulating valve (14) is provided between the condensate pump (16) and the condensate tank (23); a low-temperature condensate regulating valve (15) is provided between the condensate pump (16) and the cooling plate heat exchanger assembly.

9. A high speed axial exhaust steam turbine power generation system of claim 6, wherein The condensate pump (16), chilled water pump (17), electric chiller (18), cooling plate heat exchanger and water ring vacuum pump (10.2) are all set up in two groups, one group is working and the other group is on standby.

10. A high speed axial exhaust steam turbine power generation system of claim 1, wherein The first steam-water separator (1) is configured as a cyclone separator.

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