CN213540516U - Water supply heat regeneration system of steam turbine - Google Patents
Water supply heat regeneration system of steam turbine Download PDFInfo
- Publication number
- CN213540516U CN213540516U CN202022426315.6U CN202022426315U CN213540516U CN 213540516 U CN213540516 U CN 213540516U CN 202022426315 U CN202022426315 U CN 202022426315U CN 213540516 U CN213540516 U CN 213540516U
- Authority
- CN
- China
- Prior art keywords
- steam
- pressure
- low
- turbine
- heating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The utility model relates to a steam turbine water supply backheat technical field specifically relates to steam turbine water supply backheat system. Steam turbine feedwater backheat system includes steam turbine (1) and according to fluidic flow direction low pressure heating unit, deoxidization unit and the high pressure heating unit of establishing ties in proper order, low pressure heating unit is including parallelly connected first low pressure heating module and second low pressure heating module, first low pressure heating module with the extraction of steam turbine (1) is as heating steam source, second low pressure heating module uses chemical industry return steam as heating steam source. The steam turbine water supply regenerative system can utilize chemical industry returned steam to the maximum extent, improves the economical efficiency of the operation of the regenerative system, reduces the high-grade steam extraction use of the steam turbine, and increases the generating capacity of the steam turbine unit.
Description
Technical Field
The utility model relates to a steam turbine water supply backheat technical field specifically relates to steam turbine water supply backheat system.
Background
In the current project for preparing low-carbon olefin from large-scale coal, a thermal power station boiler is taken as a power center of a steam system of a whole plant, and high-pressure steam which is generated by the boiler and has the pressure of 9.8MPa and the temperature of more than 540 ℃ is used for driving turbines such as an air separation compressor, a conversion steam compressor, a DMTO reaction steam compressor and the like; a heat supply type steam turbine matched with a boiler or a temperature and pressure reducing device of 9.8/4.2MPa is used for providing steam of about 4.2MPa and 400 ℃ to drive turbines such as an ice purifying machine, a methanol synthetic steam compressor, an olefin separation product steam compressor and the like; the byproduct steam of the chemical system, namely the medium-low pressure level at about 1.7MPa and 380 ℃, the low-low pressure level at about 1.1MPa and 250 ℃ and the low-low pressure level at about 0.46MPa and 200 ℃, is preferentially used in the process system, and after the process system is used, the redundant byproduct steam is returned to the power station boiler steam turbine water supply regenerative system for recycling.
At present, the following problems generally exist in a water supply regenerative system of a large coal-to-low carbon olefin turbine: steam extraction of the steam turbine and chemical byproduct steam are not matched with each other for use tightly, return steam of the chemical byproduct is not fully recycled, and a steam turbine water supply heat recovery system is not economical to operate; the high-grade steam extraction of the steam turbine is large in usage amount, and the generating capacity of the unit is reduced; because the low-pressure heater of the heat recovery system uses improper low-pressure grade steam recovery, the steam extraction quantity of a steam turbine medium pressure cylinder used by the low-pressure heater matched with the steam turbine is seriously reduced, the steam flow of last stage blades of the steam turbine is increased, and the last stage blades are seriously corroded by water; the heat regenerative system has the problems that the water supply temperature of the heat regenerative system is too low or too high due to frequent fluctuation of chemical steam return and the load of a steam turbine, and the heat regenerative system cannot be flexibly adjusted; the water supply of the coal-to-low carbon olefin steam turbine consists of condensed water after the steam turbine applies work, condensed water after the air separation turbine applies work, desalted water for supplementing system loss and the like, the system water supply capacity is far larger than the amount of the condensed water after the pure steam turbine applies work, and if a back heating system is not provided with a standby heating steam source under the working conditions of start-up of a whole plant, chemical steam return failure and steam turbine failure, the water supply temperature is too low, the low-load operation of a boiler is caused, and the requirement of the external steam supply amount cannot be met.
SUMMERY OF THE UTILITY MODEL
The utility model aims at overcoming the steam turbine that exists among the prior art and giving water and returning heat the system operation uneconomic, the steam turbine high-grade steam extraction use amount is big, and the technical problem of steam turbine unit generated energy reduction provides a steam turbine and gives water and returns heat the system, and this steam turbine gives water and returns heat the system and can utilize the chemical industry to return vapour by furthest, improves the economic nature of the operation of heat system, reduces the steam turbine high-grade steam extraction use, increases the steam turbine unit generated energy.
In order to realize the above object, the utility model provides an aspect provides a steam turbine water supply backheat system, steam turbine water supply backheat system includes the steam turbine and according to fluidic flow direction low pressure heating unit, deoxidization unit and the high pressure heating unit of establishing ties in proper order, low pressure heating unit is including parallelly connected first low pressure heating module and second low pressure heating module, first low pressure heating module with the extraction of steam turbine is as heating steam source, second low pressure heating module returns the vapour as heating steam source with the chemical industry.
Preferably, the first low-pressure heating module comprises a plurality of low-pressure heaters connected in series, and the plurality of low-pressure heaters respectively adopt extraction steam with different pressures and different temperatures from a steam turbine as a heating steam source.
Preferably, the first low-pressure heating module comprises three first low-pressure heaters, a second low-pressure heater and a third low-pressure heater which are connected in series in the flow direction of the fluid, wherein:
the first low-pressure heater takes 6-stage non-regulated extraction steam at 0.05MPa and 85 ℃ of the steam turbine as a heating steam source, the second low-pressure heater takes 5-stage non-regulated extraction steam at 0.17MPa and 128 ℃ of the steam turbine as a heating steam source, and the third low-pressure heater takes 4-stage non-regulated extraction steam at 0.46MPa and 213 ℃ of the steam turbine as a heating steam source; and/or the presence of a gas in the gas,
the third low-pressure heater is connected with a first temperature and pressure reducer so as to use the gas from the temperature and pressure reducer as a standby heating steam source.
Preferably, the second low-pressure heating module includes a fourth low-pressure heater connected in parallel with the third low-pressure heater.
Preferably, the fourth low-pressure heater takes chemical industry return steam with the pressure of 0.46MPa and the temperature of 200 ℃ as a heating steam source; and/or a regulating valve is arranged on an inlet condensate pipe of the fourth low-pressure heater.
Preferably, the oxygen removing unit comprises a high-pressure oxygen remover and a low-pressure oxygen remover connected to the high-pressure oxygen remover, and the high-pressure oxygen remover is connected with the third low-pressure heater and the fourth low-pressure heater respectively.
Preferably, the low-pressure deaerator takes 4-stage non-regulated extraction steam of 0.46MPa and 213 ℃ of the steam turbine as a heating steam source; and/or the low-pressure deaerator is connected with a second temperature and pressure reducing device so as to use the gas coming from the temperature and pressure reducing device as a standby heating steam source.
Preferably, the high-pressure deaerator takes 3-stage unadjusted extraction steam at 1.1MPa and 250 ℃ of the steam turbine and chemical return steam at 1.1MPa and 250 ℃ as heating steam sources; and/or the high-pressure deaerator is connected with a third temperature and pressure reducing device so as to take gas from the temperature and pressure reducing device as a standby heating steam source.
Preferably, the high-pressure heating unit comprises a first high-pressure heater and a second high-pressure heater which are connected in series, and the first high-pressure heater is connected with the oxygen removing unit.
Preferably, the first high-pressure heater takes 2-stage non-regulated extraction steam at 1.7MPa and 388 ℃ and chemical return steam at 1.7MPa and 380 ℃ of the steam turbine as heating steam sources; and/or the second high-pressure heater takes 1-stage non-regulated extraction steam of 2.43MPa and 430 ℃ of the steam turbine as a heating steam source.
Preferably, a regulating valve is arranged on the steam extraction pipeline of the second high-pressure heater; and/or an electric valve and a check valve are arranged on the steam extraction pipeline of the second high-pressure heater.
By the technical scheme, when chemical steam return is normal, the steam extraction of the steam turbine is closed, and the chemical steam return independently heats the deoxidizing unit; when the chemical industry returns the vapour volume and is not enough, put into use with the extraction of steam turbine, the steam extraction of steam turbine and chemical industry returns the vapour and combines to use together this moment. Therefore, on one hand, chemical industry return steam can be recycled to the maximum extent, and the running economy of the heat recovery system is improved; on the other hand, the usage amount of high-grade steam extraction of the steam turbine is reduced, and the power generation amount of the steam turbine is increased; meanwhile, the second low-pressure heating module is independently arranged to recover the returned steam, the chemical returned steam does not enter the first low-pressure heating module, so that the steam extracted by the steam turbine intermediate pressure cylinder can enter the first low-pressure heating module to the maximum extent for use, and water erosion of the last-stage blade of the steam turbine unit can be reduced.
Drawings
Fig. 1 is a flow chart of the steam turbine feedwater regenerative system of the present invention.
Description of the reference numerals
1. A steam turbine; 2. a first low pressure heater; 3. a second low pressure heater; 4. a third low pressure heater; 5. a high pressure deaerator; 6. a low pressure deaerator; 7. a first high pressure heater; 8. a second high pressure heater; 9. an electrically operated valve; 10. adjusting a valve; 11. a check valve; 12. and a fourth low pressure heater.
Detailed Description
The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings. It is to be understood that the description of the embodiments herein is for purposes of illustration and explanation only and is not intended to limit the invention.
In order to realize the aim, the utility model provides a steam turbine water supply backheating system is applicable to in the production of coal system low carbon olefin. Steam turbine feedwater backheat system includes steam turbine 1 and according to fluidic flow direction low pressure heating unit, deoxidization unit and the high pressure heating unit of establishing ties in proper order, low pressure heating unit is including parallelly connected first low pressure heating module and second low pressure heating module, first low pressure heating module with steam extraction of steam turbine 1 is as the heating vapour source, second low pressure heating module returns the vapour as the heating vapour source with the chemical industry.
By the technical scheme, when chemical industry return steam is normal, the steam extraction of the steam turbine 1 is closed, and the chemical industry return steam independently heats the deoxidizing unit; when the chemical industry returns the vapour volume and is not enough, put into use with the extraction of steam turbine 1, steam extraction and the chemical industry returns the vapour and combines together to use this moment steam turbine 1. Therefore, on one hand, chemical industry return steam can be recycled to the maximum extent, and the running economy of the heat recovery system is improved; on the other hand, the usage amount of high-grade steam extraction of the steam turbine 1 is reduced, and the power generation amount of the steam turbine 1 is increased; simultaneously, the second low-pressure heating module is independently arranged to recover the returned steam, the chemical returned steam does not enter the first low-pressure heating module, so that the steam extracted by the intermediate pressure cylinder of the steam turbine 1 can be furthest used by entering the first low-pressure heating module, and the water erosion of the last-stage blade of the steam turbine 1 group can be reduced.
In one embodiment, the first low-pressure heating module comprises a plurality of low-pressure heaters connected in series, and the plurality of low-pressure heaters use extraction steam of different pressures and different temperatures from the steam turbine 1 as a heating steam source.
As an embodiment, as shown in fig. 1, the first low-pressure heating module includes three first low-pressure heaters 2, second low-pressure heaters 3, and third low-pressure heaters 4 connected in series in the flow direction of the fluid, wherein: the first low-pressure heater 2 uses 6-stage non-regulated extraction steam of 0.05MPa and 85 ℃ of the steam turbine 1 as a heating steam source, the second low-pressure heater 3 uses 5-stage non-regulated extraction steam of 0.17MPa and 128 ℃ of the steam turbine 1 as a heating steam source, and the third low-pressure heater 4 uses 4-stage non-regulated extraction steam of 0.46MPa and 213 ℃ of the steam turbine 1 as a heating steam source. Optionally, a check valve 11 and an electric valve 9 are respectively disposed on the steam extraction pipeline connecting the first low-pressure heater 2 and the steam turbine 1, the steam extraction pipeline connecting the second low-pressure heater 3 and the steam turbine 1, and the steam extraction pipeline connecting the third low-pressure heater 4 and the steam turbine 1, wherein the check valve 11 on each steam extraction pipeline is disposed near the steam turbine 1, and the electric valve 9 on each steam extraction pipeline is disposed near the low-pressure heater.
In one embodiment, a first temperature and pressure reducer is connected to the third low pressure heater 4, so that the gas from the temperature and pressure reducer is used as a backup heating gas source. Optionally, the first temperature and pressure reducer is a 1.1/0.46MPa temperature and pressure reducer.
As an embodiment, as shown in fig. 1, the second low-pressure heating module comprises a fourth low-pressure heater 12 connected in parallel with the third low-pressure heater 4.
In one embodiment, the fourth low pressure heater 12 uses chemical industry return steam with pressure of 0.46MPa and temperature of 200 ℃ as a heating steam source. Optionally, an electric valve 9 is disposed on a steam return pipeline connected with the fourth low-pressure heater 12 for conveying chemical industry steam return.
In one embodiment, as shown in fig. 1, an adjusting valve 10 is disposed on an inlet condensate pipe of the fourth low pressure heater 12.
As an embodiment, as shown in fig. 1, the oxygen removing unit includes a high pressure oxygen remover 5 and a low pressure oxygen remover 6 connected to the high pressure oxygen remover 5, and the high pressure oxygen remover 5 is connected to the third low pressure heater 4 and the fourth low pressure heater 12, respectively. Optionally, the low pressure deaerator 6 is connected with the high pressure deaerator 5 through a relay water pump.
In one embodiment, the low-pressure deaerator 6 uses a 4-stage unregulated extraction steam of 213 ℃ at 0.46MPa of the steam turbine 1 as a heating steam source. Namely, the 4-stage extraction steam of the steam turbine 1 is respectively used as the heating steam source of the third low-pressure heater 4 and the low-pressure deaerator 6.
In one embodiment, the low pressure deaerator 6 is connected with a second temperature and pressure reducing device to use the gas coming from the temperature and pressure reducing device as a standby heating gas source. Optionally, the second temperature and pressure reducer is a 9.8/4.2MPa temperature and pressure reducer.
In one embodiment, the high-pressure deaerator 5 uses 1.1MPa and 250 ℃ 3-stage non-regulated extraction steam of the steam turbine 1 and 1.1MPa and 250 ℃ chemical industry return steam as heating steam sources. Combining low-pressure-level chemical industry return steam at about 1.1MPa and 250 ℃ with 1.1 MPa-level steam extraction of a steam turbine, and feeding the combined steam into a high-pressure deaerator 5, when the 1.1MPa chemical industry return steam is normal, closing the 1.1MPa steam extraction of the steam turbine 1, and independently heating the high-pressure deaerator 5 by the 1.1MPa chemical industry return steam; when the chemical industry 1.1MPa steam return quantity is insufficient, 1.1MPa grade steam extraction of the steam turbine 1 is put into use, and at the moment, the 1.1MPa steam extraction of the steam turbine and the chemical industry 1.1MPa steam return are combined to be used together. Therefore, on one hand, chemical industry return steam can be recovered to the maximum extent; on the other hand, the usage amount of high-grade extraction steam of the steam turbine 1.1MPa is reduced, and the power generation amount of the steam turbine 1 can be increased. The steam extraction pipeline of the steam turbine at 1.1MPa is provided with a steam extraction quick-closing check valve 11 and an electric valve 9, and the electric valve 9 can open and close the steam extraction and properly adjust the steam extraction. The 1.1MPa steam return pipeline is provided with an electric valve 9 which can properly adjust the steam return. Normally, in order to reduce steam scouring and running resistance on the sealing surface of the valve, the electric valves 9 of the steam extraction pipeline and the steam return pipeline only carry out full-open and full-close operations.
In one embodiment, the high-pressure deaerator 5 is connected with a third temperature and pressure reducing device to use the incoming gas of the temperature and pressure reducing device as a standby heating steam source. Optionally, the third temperature and pressure reducer is a 4.2/1.1MPa temperature and pressure reducer.
In one embodiment, the high-pressure heating unit comprises a first high-pressure heater 7 and a second high-pressure heater 8 which are connected in series, and the first high-pressure heater 7 is connected with the oxygen removing unit. Specifically, the first high-pressure heater 7 is connected with the high-pressure deaerator 5 through a feed water pump.
In one embodiment, the first high-pressure heater 7 uses 2-stage unregulated extraction steam at 388 ℃ and chemical back-flow steam at 380 ℃ of 1.7MPa of the steam turbine 1 as heating steam sources. Combining the medium-low pressure grade chemical industry return steam of about 1.7MPa and 380 ℃ with the 1.7MPa grade extraction steam of the steam turbine 1 and entering the first high-pressure heater 7, when the 1.7MPa chemical industry return steam is normal, closing the extraction steam of the steam turbine 1, and independently heating the first high-pressure heater 7 by the chemical industry 1.7MPa return steam; when the chemical industry 1.7MPa steam return quantity is insufficient, 1.7MPa grade steam extraction of the steam turbine 1 is put into use, and at the moment, the 1.7MPa steam extraction of the steam turbine and the chemical industry 1.7MPa steam return are combined to be used together. Therefore, on one hand, chemical industry return steam can be recovered to the maximum extent; on the other hand, the usage amount of high-grade extraction steam of the steam turbine at 1.7MPa can be reduced, the generated energy of the steam turbine 1 can be increased, and meanwhile, the investment can be reduced by combining the return steam and the extraction steam and using the same heater. The steam extraction pipeline of the steam turbine 11.7MPa is provided with a steam extraction quick-closing check valve 11 and an electric valve 9, and the electric valve 9 can open and close the steam extraction and properly adjust the steam extraction. The electric valve 9 arranged on the steam return pipeline can properly adjust the steam extraction. Normally, in order to reduce the steam scouring and the running resistance to the sealing surface of the valve, the electric valves 9 of the steam extraction pipeline and the steam return pipeline only carry out full-open and full-close operation.
In one embodiment, the second high pressure heater 8 uses a 1-stage unregulated extraction steam of 430 ℃ at 2.43MPa of the steam turbine 1 as a heating steam source.
In one embodiment, the steam extraction pipe of the second high-pressure heater 8 is provided with a regulating valve 10.
In one embodiment, the steam extraction pipe of the second high-pressure heater 8 is provided with an electric valve 9 and a check valve 11. The check valve 11, the regulating valve 10, and the electric valve 9 are provided in this order in the flow direction of the fluid. The steam extraction and chemical steam return parameters and the water supply quantity of the steam turbine water supply heat return system are constantly changed, the water supply temperature is possibly too low or overtemperature, a final-stage second high-pressure heater 8 is arranged according to the lowest and highest temperature rise ranges of the final water supply temperature of the heaters at the previous stages, the steam extraction of the steam turbine is used as a heating steam source, an electric isolating valve, a steam extraction check valve 11 and an adjusting valve 10 are arranged on a steam extraction pipeline, the steam extraction adjusting valve 10 of the steam turbine 1 is arranged to flexibly adjust the water supply temperature by adjusting the opening degree of the steam extraction adjusting valve 10, and the overtemperature is prevented, so that the water temperature of the final-stage heater can be flexibly controlled according to the change of the chemical steam return and the load of.
The chemical industry return steam and the steam extracted by the steam turbine 1 are jointly used as a heating steam source of the steam turbine water supply heat recovery system, the chemical industry return steam is utilized to the maximum extent, and the running economy of the steam turbine water supply heat recovery system is improved; the high-grade steam extraction use of the steam turbine 1 is reduced, and the generating capacity of a steam turbine unit is increased; the fourth low-pressure heater 12 is independently arranged, chemical low-pressure grade return steam is taken as a heating steam source, the return steam is recovered to the maximum extent, and the first low-pressure heater 2, the second low-pressure heater 3 and the third low-pressure heater 4 matched with the steam turbine 1 only use each stage of steam extraction of a medium-pressure cylinder of the steam turbine 1, so that water erosion of a final-stage blade of the steam turbine unit is reduced; due to the characteristics of chemical steam return and load instability of the steam turbine 1, the water supply temperature rise of heaters (including low-pressure heaters and high-pressure heaters) at all stages in the steam turbine water supply regenerative system for preparing low-carbon olefins from coal cannot be set completely according to the conventional isothermal rise distribution principle, the last-stage heater (namely, the second high-pressure heater 8) needs to select proper steam extraction parameters of the steam turbine 1 according to the temperature rise of the heaters at all stages, an adjusting valve 10 is arranged on a steam extraction pipeline, and the final temperature of water can be flexibly controlled by adjusting the opening degree of the steam extraction adjusting valve 10 according to the chemical steam return and the load change of the steam turbine 1 by the last-stage heater (the second high-pressure heater 8).
The first low-pressure heating module and the second low-pressure heating module are arranged in double rows, and the second low-pressure heating module (a fourth low-pressure heater 12) takes chemical low-pressure-level return steam of 0.46MPa and 200 ℃ as a heating steam source; the first low-pressure heating module takes the extracted steam of the intermediate pressure cylinder of the steam turbine 1 as a heating steam source, and condensed water enters the high-pressure deaerator 5 after being heated by the low-pressure heaters arranged in double rows. Because the last blade of low pressure jar of steam turbine 1 is in wet steam district work, low pressure heater's extraction steam is stopped or is reduced and use, can cause the steam flow increase of the last several grades of steam turbine 1 and lead to last blade cavitation aggravation, and chemical industry returns vapour and does not get into first low pressure heating module for steam turbine 1 intermediate pressure jar extraction steam furthest's the first low pressure heating module of entering uses, reduces last blade water erosion. The low-pressure extraction steam of the steam turbine 1 does not enter the second low-pressure heating module, and the chemical low-pressure stage return steam can be recovered to the maximum extent. The purpose of flexibly controlling the condensed water quantity of each row of heaters can be achieved by arranging the regulating valve 10 on the condensed water pipe at the inlet of the second low-pressure heating module, and the temperature rise of the low-pressure heaters arranged in each row can be kept within a qualified range according to the change of respective heating steam.
The coal-to-olefin power station is arranged according to the principle of heat for fixing power, and generally comprises 2 small-capacity steam turbines 1 matched with a plurality of large-capacity boilers, the water supply of the coal-to-low-carbon olefin steam turbine is composed of condensed water produced by the steam turbine 1, condensed water produced by an air separation turbine after work, desalted water lost by a replenishing system and the like, and the water supply capacity of the system is far larger than the condensed water produced by the pure steam turbine 1 after work, so that the heating steam of a water supply regenerative system can meet the water supply temperature requirement of the boilers only by mutually combining chemical steam return and steam extraction of the steam turbine 1, and under the working conditions of start-up, stop-working, chemical steam return fault and steam turbine 1 fault (more than two sets of zero machine working conditions or stop-working of a vaporizing device and the like), temperature and pressure reducers of 9.8/4.2MPa, 4.2/1.1MPa and 1.1/0.46MPa are arranged in the power station and respectively used, The standby heating steam sources of the low-pressure deaerator 6 and the third low-pressure heater 4 enable the feed water temperature of the feed water regenerative system to meet the requirement of boiler operation.
Example 1
The method comprises the steps of producing methanol from certain coal-made low-carbon olefin by adopting a coal water slurry pressure vaporization technology, converting the methanol into the olefin through an MTO device, producing polypropylene and polyethylene through a polymerization device, and simultaneously producing byproducts such as sulfur, butylene, propane and ethane and byproducts such as C5 +. The oxygen steam output of 4 sets of air separation devices is designed to be 4 multiplied by 6 ten thousand Nm3/h, the effective synthetic steam output of 5 Kelvin vaporizing furnaces of 7 vaporizing devices is 54 ten thousand Nm3/h, the MTO grade methanol output is designed to be 180 ten thousand tons/year, the polyethylene output is designed to be 30 ten thousand tons/year, the polypropylene output is 30 ten thousand tons/year, and a thermal power station provides steam and electric power for the whole plant.
The thermal power station is provided with 4 480t/h (3 operation 1 spare) high-pressure pulverized coal boilers and 250 MW heat supply turbines 1. 3 480t/h high-pressure pulverized coal boilers of the thermal power station provide superheated steam with the pressure of 9.8MPa and the temperature of 540 ℃; under the normal operation working condition of chemical industry, the total steam yield of superheated steam provided by a boiler is about 1200t/h at the temperature of 540 ℃, wherein 600t/h high-pressure superheated steam is provided for 4 sets of air separation compressor turbines in a whole plant, and 560t/h high-pressure superheated steam is provided for 2 matched extraction-condensation type steam turbine generator units with 50MW once adjustment; the 4.2MPa and 420 ℃ adjustable extraction design output of a single turbine is 140 t/h; when the chemical system normally operates, 4.2MPa steam required by the turbines of the methanol synthesis compressor, the ice purifier and the olefin propylene separator in the chemical industry needs to be provided with about 130t/h power steam by the turbine of the power station except the byproduct of the chemical system.
The steam turbine 1 is provided with 6-stage unadjusted extraction and chemical 1.7MPa, 1.1MPa and 0.46MPa return steam which are used as heating steam sources of a heat recovery system together, each steam turbine 1 is provided with 1 series of water supply heat recovery heating systems, the total water supply flow of the 3-furnace 2 machine is 1440t/h, the boiler water supply temperature is 205 ℃ under the rated extraction working condition of the steam turbine 1, and the water supply temperature is 220 ℃ under the rated output pure condensation working condition of the steam turbine 1. When the chemical system normally operates, 57t/h of low-pressure steam at 1.7MPa and 380 ℃, 80t/h of low-pressure steam at 1.1MPa and 250 ℃, 38t/h of low-pressure steam at 0.46MPa and 200 ℃ can be provided for the thermal power station.
The regenerative water heating system of each steam turbine 1 is provided with 2-stage high-pressure heating, 1-stage high-pressure deaerator and 3-stage low-pressure heater, and a first low-pressure heating module (comprising a first low-pressure heater 2, a second low-pressure heater 3 and a third low-pressure heater 4 which are connected in series) and a second low-pressure heating module (a fourth low-pressure heater 12) are arranged in two rows, as shown in fig. 1.
The first low-pressure heater 2 of the heat recovery system takes 6-stage 0.05MPa and 85 ℃ non-regulated extraction steam of a steam turbine 1 as a heating steam source, the water temperature of the inlet of the heater is 54 ℃, the water temperature of the outlet of the heater is 77.9 ℃, and the extraction steam flow is 19 t/h; the second low-pressure heater 3 takes 5-grade non-regulated extraction steam with the pressure of 0.17MPa and the temperature of 128 ℃ as a heating steam source, the water temperature of an inlet of the heater is 77.9 ℃, the water temperature of an outlet of the heater is 111.2 ℃, and the extraction steam flow is 32 t/h; the third low-pressure heater 4 takes 4-level non-regulated extraction steam at the temperature of 213 ℃ and the pressure of 0.46MPa as a heating steam source, the water temperature at the inlet is 111.2 ℃, the water temperature at the outlet is 142.7 ℃, and the extraction steam flow is 32 t/h; chemical return steam from a low-pressure steam pipe network with the pressure of 0.46MPa and the temperature of 200 ℃ can enter the fourth low-pressure heater 12 of the #1 machine and the # 2 machine. Each steam turbine 1 is independently provided with 1 fourth low-pressure heater 12 which is connected with a first low-pressure heating module (comprising a first low-pressure heater 2, a second low-pressure heater 3 and a third low-pressure heater 4 which are connected in series) in parallel for use, and chemical return steam with the pressure of 0.46MPa and the temperature of 200 ℃ is fully recovered, wherein the inlet water temperature of the heaters is 54 ℃ and the outlet water temperature of the heaters is 142.7 ℃. The 4-stage extraction steam of the steam turbine 1 also serves as a heating steam source of the low-pressure deaerator 6.
The first low-pressure heating module (comprising a first low-pressure heater 2, a second low-pressure heater 3 and a third low-pressure heater 4 which are connected in series) fully uses the steam extraction of the intermediate pressure cylinder of the steam turbine 1 to prevent the cavitation of the low-pressure final-stage blade of the steam turbine 1, and the fourth low-pressure heater 12 is independently arranged to recover chemical industry return steam to the maximum extent. The first low-pressure heating module (comprising the first low-pressure heater 2, the second low-pressure heater 3 and the third low-pressure heater 4) and the fourth low-pressure heater 12 drain water and return to the condenser of the steam turbine 1. The regulating valve 10 is arranged on the inlet condensate pipe of the fourth low-pressure heater 12, so that the aim of flexibly controlling the condensate water quantity of each row of heaters is fulfilled, and the low-pressure heaters arranged in each row can keep the temperature rise within a qualified range according to the change of respective heating steam.
The 2 steam turbines 1 are provided with 4 high-pressure deaerators 5, the 3-level 1.1MPa steam extraction and 250 ℃ return steam of the steam turbines 1 and the chemical industry 1.1MPa and 250 ℃ return steam are used as heating steam sources, the high-pressure deaerators 5 operate at a constant pressure, the working pressure of the deaerators is 0.58MPa, and the water outlet temperature of the deaerators is 159 ℃. Chemical industry return steam from a 1.1MPa, 250 ℃ low-pressure steam pipe network is mutually communicated with 3-stage 1.1MPa, 250 ℃ non-adjustment steam extraction of a #1 machine and a # 2 machine, when the chemical industry return steam is normal, the 3-stage non-adjustment steam extraction of the steam turbine 1 is closed, and the 1.1-stage chemical industry return steam is used to the maximum extent. The 1.1MPa steam return pipeline and the steam extraction pipeline of the steam turbine 1 are both provided with electric valves 9, steam can be properly adjusted, and under the normal condition, in order to reduce steam scouring and running resistance on the sealing surface of the valve, the electric valves 9 of the steam extraction pipeline and the steam return pipeline only carry out full-open and full-close operations.
The first high-pressure heater 7 takes 2-stage 1.7MPa, 388 ℃ unadjusted extraction steam and 1.7MPa, 380 ℃ chemical industry return steam of the steam turbine 1 as heating steam sources. The inlet temperature is 159 ℃, the outlet temperature is 202 ℃, and the extraction flow rate is 52.91 t/h. Chemical return steam from a 1.7MPa and 380 ℃ steam pipe network respectively enters the first high-pressure heaters 7 of the #1 machine and the # 2 machine, is communicated with 2-stage extraction steam of the steam turbine 1 and is jointly used as a heating steam source; when the steam return is normal, the 2-stage steam extraction of the steam turbine 1 is closed, the water supply of the first high-pressure heater 7 is heated by the steam return, 1.7MPa chemical industry steam return is recovered to the maximum degree, and the 12-stage steam extraction of the steam turbine is closed, so that the use of high-grade steam of the steam turbine 1 is reduced, and the power generation capacity of the steam turbine 1 is increased. The 1.7MPa steam return pipeline and the steam extraction pipeline of the steam turbine 1 are both provided with an electric valve 9, steam can be properly adjusted, and under the normal condition, in order to reduce steam scouring on the sealing surface of the valve, the electric valves 9 of the steam extraction pipeline and the steam return pipeline only carry out full-open and full-close operations. The drained water returns to the high pressure deaerator 5.
The second high-pressure heater 8 takes 1-stage 2.43MPa and 430 ℃ non-regulated extraction steam of the steam turbine 1 as a heating steam source, the inlet temperature of the heater is 202 ℃, the outlet water temperature is 219 ℃, and the extraction steam flow is 26.63 t/h. The steam extraction pipeline is provided with an electric isolation valve, a pneumatic check valve 11 and an electric regulating valve 10. According to the change of the working condition, the water supply temperature can be flexibly adjusted by adjusting the opening of the adjusting valve 10, and the over-temperature or the insufficient water supply temperature of the water supply temperature can be prevented. The drained water returns to the high pressure deaerator 5.
The water supply regenerative heating system is provided with an auxiliary heating steam source, and when the working conditions of starting and stopping of the whole plant are considered, the working condition of zero machine or the running of the vaporizing device is more than two sets, no chemical steam return or insufficient steam return is generated, and 2 120t/h temperature and pressure reducers of 4.1/1.1MPa are arranged for ensuring the water supply temperature of the boiler to heat the high-pressure deaerator 5. 1.1/0.46MPa temperature and pressure reducer of 72t/h is arranged to heat the low-pressure deaerator 6 and the third low-pressure heater 4. The requirement of the boiler on the feed water temperature is met to the maximum extent.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited thereto. The technical scheme of the utility model in the technical conception scope, can be right carry out multiple simple variant. Including each of the specific features, are combined in any suitable manner. In order to avoid unnecessary repetition, the present invention does not separately describe various possible combinations. These simple variations and combinations should also be considered as disclosed in the present invention, all falling within the scope of protection of the present invention.
Claims (11)
1. The utility model provides a steam turbine water supply backheat system, its characterized in that, steam turbine water supply backheat system includes steam turbine (1) and according to fluidic flow direction low pressure heating unit, deoxidization unit and the high pressure heating unit of establishing ties in proper order, low pressure heating unit is including parallelly connected first low pressure heating module and second low pressure heating module, first low pressure heating module with the extraction of steam turbine (1) is as heating steam source, the second low pressure heating module returns the vapour as heating steam source with the chemical industry.
2. The turbine feedwater regenerative system of claim 1, wherein the first low pressure heating module comprises a plurality of low pressure heaters connected in series, the plurality of low pressure heaters using extraction steam from the turbine (1) at different pressures and different temperatures as a heating steam source.
3. The turbine feedwater regenerative system of claim 2, wherein: the first low-pressure heating module comprises a first low-pressure heater (2), a second low-pressure heater (3) and a third low-pressure heater (4) which are sequentially connected in series according to the flowing direction of fluid, wherein:
the first low-pressure heater (2) takes 6-stage non-regulated extraction steam of 0.05MPa and 85 ℃ of the steam turbine (1) as a heating steam source, the second low-pressure heater (3) takes 5-stage non-regulated extraction steam of 0.17MPa and 128 ℃ of the steam turbine (1) as a heating steam source, and the third low-pressure heater (4) takes 4-stage non-regulated extraction steam of 0.46MPa and 213 ℃ of the steam turbine (1) as a heating steam source; and/or the presence of a gas in the gas,
and the third low-pressure heater (4) is connected with a first temperature and pressure reducer to use the gas from the temperature and pressure reducer as a standby heating steam source.
4. The turbine feedwater regenerative system of claim 3, wherein the second low-pressure heating module comprises a fourth low-pressure heater (12) in parallel with the third low-pressure heater (4).
5. The turbine feedwater regenerative system of claim 4, wherein: the fourth low-pressure heater (12) takes chemical industry return steam with the pressure of 0.46MPa and the temperature of 200 ℃ as a heating steam source; and/or the presence of a gas in the gas,
and an adjusting valve (10) is arranged on an inlet condensate pipe of the fourth low-pressure heater (12).
6. The steam turbine feedwater regenerative system of claim 4, wherein the deaerating unit comprises a high pressure deaerator (5) and a low pressure deaerator (6) connected to the high pressure deaerator (5), the high pressure deaerator (5) being connected to the third low pressure heater (4) and the fourth low pressure heater (12), respectively.
7. The turbine feedwater regenerative system of claim 6, wherein:
the low-pressure deaerator (6) takes 4-stage unadjusted extraction steam of 0.46MPa and 213 ℃ of the steam turbine (1) as a heating steam source; and/or the presence of a gas in the gas,
and the low-pressure deaerator (6) is connected with a second temperature and pressure reducing device so as to use the gas from the temperature and pressure reducing device as a standby heating steam source.
8. The turbine feedwater regenerative system of claim 6, wherein:
the high-pressure deaerator (5) takes 3-stage unadjusted extraction steam at 1.1MPa and 250 ℃ of the steam turbine (1) and chemical return steam at 1.1MPa and 250 ℃ as heating steam sources; and/or the presence of a gas in the gas,
and the high-pressure deaerator (5) is connected with a third temperature and pressure reducing device to use the gas coming from the temperature and pressure reducing device as a standby heating steam source.
9. The turbine feedwater regenerative system of claim 1, wherein the high pressure heating unit comprises a first high pressure heater (7) and a second high pressure heater (8) in series, the first high pressure heater (7) being connected to the oxygen removal unit.
10. The turbine feedwater regenerative system of claim 9, wherein:
the first high-pressure heater (7) takes 2-stage non-regulated extraction steam at 1.7MPa and 388 ℃ and chemical return steam at 1.7MPa and 380 ℃ of the steam turbine (1) as heating steam sources; and/or the presence of a gas in the gas,
the second high-pressure heater (8) takes 1-stage non-regulated extraction steam with the pressure of 2.43MPa and the temperature of 430 ℃ of the steam turbine (1) as a heating steam source.
11. The turbine feedwater regenerative system of claim 9, wherein:
an adjusting valve (10) is arranged on a steam extraction pipeline of the second high-pressure heater (8); and/or the presence of a gas in the gas,
an electric valve (9) and a check valve (11) are arranged on the steam extraction pipeline of the second high-pressure heater (8).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022426315.6U CN213540516U (en) | 2020-10-27 | 2020-10-27 | Water supply heat regeneration system of steam turbine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022426315.6U CN213540516U (en) | 2020-10-27 | 2020-10-27 | Water supply heat regeneration system of steam turbine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213540516U true CN213540516U (en) | 2021-06-25 |
Family
ID=76501097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022426315.6U Active CN213540516U (en) | 2020-10-27 | 2020-10-27 | Water supply heat regeneration system of steam turbine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213540516U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113864750A (en) * | 2021-08-30 | 2021-12-31 | 国核电力规划设计研究院有限公司 | Heating system of nuclear power plant |
-
2020
- 2020-10-27 CN CN202022426315.6U patent/CN213540516U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113864750A (en) * | 2021-08-30 | 2021-12-31 | 国核电力规划设计研究院有限公司 | Heating system of nuclear power plant |
| CN113864750B (en) * | 2021-08-30 | 2024-02-09 | 国核电力规划设计研究院有限公司 | Nuclear power plant heating system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110145376B (en) | Boiler and steam turbine decoupling system based on increase steam turbine | |
| CN109184812B (en) | Nuclear energy coupling chemical energy power generation system and method based on two-loop boiler | |
| CN113175362B (en) | Bus pipe connection system for realizing zero output of low-pressure cylinder and operation method | |
| CN113586185B (en) | Coal-fired boiler flue gas and steam combined heat storage deep peak regulation system and operation method | |
| CN111365748B (en) | Heat supply method and heat supply system of cogeneration unit | |
| CN111485964B (en) | Thermoelectric decoupling method for coal-fired power plant based on turboexpander | |
| CN213540516U (en) | Water supply heat regeneration system of steam turbine | |
| CN112303610A (en) | Operation system and method for recovering high-energy water in shutdown and non-shutdown operation mode | |
| CN113175367B (en) | Master control system for improving peak regulation capacity and flexibility of unit and operation method | |
| CN113250767A (en) | Four-pipeline main pipe connection system for deep peak shaving and operation method | |
| CN109279573B (en) | Isothermal transformation process matched with coal water slurry gasification | |
| CN114233421B (en) | Thermoelectric cooperative system integrated with steam injector and operation method | |
| CN111853755B (en) | Multi-source energy-based water replenishing and deoxidizing control method for condenser | |
| CN112178620A (en) | Condensed water energy utilization device of high-pressure heater of thermal power plant | |
| CN109958982A (en) | A kind of steam unit and its application for coal producing light olefins | |
| CN111206968A (en) | Subcritical complementary energy waste heat recovery power generation system of steel plant and working method thereof | |
| CN213298059U (en) | Coal burner unit heating device with backpressure small turbine matched with asynchronous generator | |
| CN113175366B (en) | Bus pipe thermal system for realizing machine-furnace decoupling and operation method | |
| CN219654752U (en) | Steam turbine system | |
| CN113494322B (en) | System for realizing interconnection between units through main pipe and operation method | |
| CN220321414U (en) | Heat supply steam system based on hot water conveying | |
| CN211900717U (en) | Subcritical complementary energy waste heat recovery power generation system of steel plant | |
| RU2432468C1 (en) | Steam-turbine thermal power plant operating method and device for its implementation | |
| CN114233419B (en) | Thermoelectric cooperative system integrated with compressor unit and operation method | |
| CN219932274U (en) | Energy supply system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |