CN116332268A - Water-electricity cogeneration system and operation method - Google Patents
Water-electricity cogeneration system and operation method Download PDFInfo
- Publication number
- CN116332268A CN116332268A CN202310180239.0A CN202310180239A CN116332268A CN 116332268 A CN116332268 A CN 116332268A CN 202310180239 A CN202310180239 A CN 202310180239A CN 116332268 A CN116332268 A CN 116332268A
- Authority
- CN
- China
- Prior art keywords
- seawater
- heat
- water
- stage flash
- flash
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 21
- 239000013535 sea water Substances 0.000 claims abstract description 205
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 105
- 238000001704 evaporation Methods 0.000 claims abstract description 89
- 230000008020 evaporation Effects 0.000 claims abstract description 89
- 239000007788 liquid Substances 0.000 claims abstract description 73
- 238000010612 desalination reaction Methods 0.000 claims abstract description 43
- 239000002994 raw material Substances 0.000 claims abstract description 40
- 238000011084 recovery Methods 0.000 claims abstract description 35
- 238000010248 power generation Methods 0.000 claims abstract description 23
- 150000003839 salts Chemical class 0.000 claims abstract description 18
- 230000005611 electricity Effects 0.000 claims abstract description 15
- 230000003204 osmotic effect Effects 0.000 claims abstract description 9
- 238000005338 heat storage Methods 0.000 claims description 67
- 239000013505 freshwater Substances 0.000 claims description 29
- 239000000498 cooling water Substances 0.000 claims description 17
- 238000000605 extraction Methods 0.000 claims description 17
- 238000009833 condensation Methods 0.000 claims description 8
- 230000005494 condensation Effects 0.000 claims description 8
- 238000004064 recycling Methods 0.000 claims description 4
- 238000005086 pumping Methods 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 7
- 238000005381 potential energy Methods 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract description 4
- 238000004891 communication Methods 0.000 description 3
- 230000002411 adverse Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
- C02F1/06—Flash evaporation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03G—SPRING, WEIGHT, INERTIA OR LIKE MOTORS; MECHANICAL-POWER PRODUCING DEVICES OR MECHANISMS, NOT OTHERWISE PROVIDED FOR OR USING ENERGY SOURCES NOT OTHERWISE PROVIDED FOR
- F03G7/00—Mechanical-power-producing mechanisms, not otherwise provided for or using energy sources not otherwise provided for
- F03G7/008—Mechanical-power-producing mechanisms, not otherwise provided for or using energy sources not otherwise provided for characterised by the actuating element
- F03G7/015—Actuators using the difference in osmotic pressure between fluids
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/08—Seawater, e.g. for desalination
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
Abstract
The invention relates to the technical field of cogeneration systems, and provides a cogeneration system and an operation method, wherein the cogeneration system comprises: the multistage flash evaporation sea water desalination system at least comprises a multistage flash evaporation heat recovery section and a multistage flash evaporation heat discharge section which are connected; the salt difference energy power generation system at least comprises a drawing liquid water tank, a raw material liquid water tank, a water turbine and a power generator. The water and electricity cogeneration system integrates the multi-stage flash evaporation sea water desalination system and the salt difference energy power generation system, takes the concentrated sea water discharged by the multi-stage flash evaporation sea water desalination system as the drawing liquid, and takes the feed sea water as the raw material liquid to generate power, thereby reducing the concentration of the discharged concentrated sea water and reducing the influence of the discharged concentrated sea water on the environment; compared with the traditional salt difference energy power generation system, the osmotic pressure difference between the drawing liquid and the raw material liquid can be improved, and the power generation efficiency is higher; in addition, the salt difference energy power generation system can convert chemical potential energy of water into electric energy, and improves energy utilization efficiency and economic benefit.
Description
Technical Field
The invention relates to the technical field of cogeneration systems, in particular to a cogeneration system and an operation method.
Background
Sea water desalination is an important approach to solve the shortage of fresh water. In many sea water desalination processes, multistage flash evaporation is in the leading position in sea water desalination industry by virtue of the advantages of large single-machine capacity, good effluent quality and the like of equipment. However, the existing seawater desalination system can generate a large amount of concentrated seawater, and the concentrated seawater can have adverse effects on the marine ecological environment after being discharged into the sea.
Disclosure of Invention
Therefore, the technical problem to be solved by the invention is that the existing sea water desalination system can generate a large amount of concentrated sea water, and the concentrated sea water can cause adverse effect on the marine ecological environment after being discharged into the sea, so as to provide a cogeneration system and an operation method.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a cogeneration system comprising: the multistage flash evaporation sea water desalination system at least comprises a multistage flash evaporation heat recovery section and a multistage flash evaporation heat discharge section which are connected; the salt difference energy power generation system at least comprises a drawing liquid water tank, a raw material liquid water tank, a water turbine and a power generator; an inlet of the drawing liquid water tank is communicated with a concentrated seawater outlet of a final-stage flash chamber of the multistage flash evaporation heat discharge section, and a mixed concentrated seawater outlet of the drawing liquid water tank is communicated with an inlet of the water turbine; the inlet of the raw material liquid water tank is communicated with an external pretreated seawater source, and the outlet of the raw material liquid water tank is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multistage flash evaporation heat discharge section; the water turbine is connected with the generator and is suitable for driving the generator to generate electricity; the liquid drawing water tank is communicated with the raw material liquid water tank, and concentrated seawater in the liquid drawing water tank can absorb fresh water in the feed seawater in the raw material liquid water tank to form mixed concentrated seawater and drive the generator to generate electricity through the water turbine.
Further, the multistage flash evaporation sea water desalination system also comprises a first water pump and a sea water pretreatment device; the seawater inlet of the seawater pretreatment device is communicated with the feed seawater, the seawater outlet of the seawater pretreatment device comprises two branches, one branch is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multistage flash evaporation heat discharge section, and the other branch is communicated with the inlet of the raw material liquid tank; the first water pump is arranged on a pipeline at the sea water inlet side of the sea water pretreatment device.
Further, the multistage flash evaporation seawater desalination system further comprises an air extractor, wherein the upper parts of the flash chambers of each stage of the multistage flash evaporation heat discharge section and the multistage flash evaporation heat recovery section are communicated with the air extractor, and the air extractor is suitable for extracting air dissolved in seawater.
Further, the cogeneration system also comprises a heater, wherein a seawater inlet of the heater is communicated with a cooling water outlet of a first-stage flash chamber of the multi-stage flash heat recovery section, and a seawater outlet of the heater is communicated with a flash seawater inlet of the first-stage flash chamber of the multi-stage flash heat recovery section; the hot side inlet of the heater is suitable for being communicated with an external steam extraction port of the turbine unit.
Further, the cogeneration system also comprises a heat storage system, at least comprising a heat storage heat exchanger and a heat storage device; the low-temperature heat source end outlet of the heat storage heat exchanger is communicated with the heat storage medium inlet of the heat storage device, and the low-temperature heat source end inlet of the heat storage heat exchanger is communicated with the heat storage medium outlet of the heat storage device; the low-temperature heat source end inlet of the heat storage device is communicated with the fresh water outlet of the final-stage flash chamber of the multi-stage flash heat discharge section, and the low-temperature heat source end outlet of the heat storage device is connected with the hot end inlet of the heater; the heat source end steam inlet of the heat storage heat exchanger is suitable for being connected with an external steam extraction port of the steam turbine unit; a first valve is arranged on a pipeline between the heat storage device and the heater; a second valve is arranged on a pipeline between the heater and an external steam extraction port of the steam turbine unit; and a valve III is arranged on a pipeline between the heat storage heat exchanger and the steam extraction port of the external turbine unit.
The operation method of the cogeneration system comprises the steps of: enabling the concentrated seawater discharged by the multistage flash evaporation seawater desalination system to flow into a liquid drawing water tank; the feed seawater enters a raw material liquid water tank, and the concentrated seawater in a drawing liquid water tank is changed into mixed concentrated seawater after absorbing fresh water in the feed seawater in the raw material liquid water tank by utilizing the osmotic pressure principle; the mixed concentrated seawater is utilized to drive the water turbine to rotate through the water pipe, so that the generator is driven to generate electricity.
Further, the feed seawater after absorbing the water in the raw material liquid water tank is mixed with the outlet seawater of the seawater pretreatment device and then enters a multistage flash evaporation seawater desalination system for recycling.
Further, when the external turbine unit does not participate in peak shaving, the third valve and the second valve are opened, and the first valve is closed; leading the extracted steam of the external turbine unit to enter a heat storage heat exchanger for heat release so as to enable the heat storage device to store heat; the steam extracted from the external turbine unit enters a heater to release heat so as to drive the multistage flash evaporation sea water desalination system to operate.
Further, when the external turbine unit participates in peak shaving, the third valve and the second valve are closed, and the first valve is opened; the heat stored by the heat storage device is utilized to drive the multistage flash evaporation sea water desalination system to operate.
Further, the multi-stage flash evaporation seawater desalination system specifically comprises: pumping the pretreated sea water into a condensation tube bundle at the upper part of a final-stage flash chamber of a multi-stage flash heat discharge section, exchanging heat with flash steam in the flash chamber step by step, and condensing the flash steam in the flash chamber into fresh water while preheating the sea water; after being preheated by the multi-stage flash evaporation heat discharge section, the feed seawater is split into two parts, one part returns to the sea, and the other part is mixed with circulating seawater in a final stage flash evaporation chamber of the multi-stage flash evaporation heat discharge section; the mixed circulating seawater is pumped into a condensation tube bundle of a final stage flash chamber of the multi-stage flash heat recovery section, flows into a heater to be further heated along the flow direction opposite to the flow direction of the flash seawater as cooling water of the flash steam into a first stage flash chamber of the multi-stage flash heat recovery section, flows into the lower part of the first stage flash chamber of the multi-stage flash heat recovery section to start flash evaporation, the evaporated steam is condensed into fresh water, and the flash seawater flows out of the final stage flash chamber of the multi-stage flash heat recovery section and enters the first stage flash chamber of the multi-stage flash heat discharge section to continue flash evaporation until the final stage flash chamber of the multi-stage flash heat discharge section discharges concentrated seawater, and the fresh water is collected.
The technical scheme of the invention has the following advantages:
the water and electricity cogeneration system integrates the multi-stage flash evaporation sea water desalination system and the salt difference energy power generation system, takes the concentrated sea water discharged by the multi-stage flash evaporation sea water desalination system as the drawing liquid, and takes the feed sea water as the raw material liquid to generate power, thereby reducing the concentration of the discharged concentrated sea water and reducing the influence of the discharged concentrated sea water on the environment; compared with the traditional salt difference energy power generation system, the osmotic pressure difference between the drawing liquid and the raw material liquid can be improved, and the power generation efficiency is higher; in addition, the salt difference energy power generation system can convert chemical potential energy of water into electric energy, and improves energy utilization efficiency and economic benefit.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic diagram of a cogeneration system in an embodiment of the invention.
1. A first water pump; 2. a seawater pretreatment device; 3. a multi-stage flash heat recovery section; 4. a multi-stage flash heat discharge section; 5. a second water pump; 6. a third water pump; 7. a draw solution tank; 8. a raw material liquid water tank; 9. a water turbine; 10. a generator; 11. a heat storage heat exchanger; 12. a heat storage device; 13. a valve I; 14. a valve II; 15. a valve III; 16. a heater; 17. a valve IV; 18. and an air extracting device.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
Fig. 1 is a schematic diagram of a cogeneration system according to an embodiment of the invention, and as shown in fig. 1, the embodiment provides a cogeneration system, including: the multi-stage flash evaporation sea water desalination system at least comprises a multi-stage flash evaporation heat recovery section 3 and a multi-stage flash evaporation heat discharge section 4 which are connected; the salt difference energy power generation system at least comprises a drawing liquid water tank 7, a raw material liquid water tank 8, a water turbine 9 and a generator 10; the inlet of the drawing liquid water tank 7 is communicated with the concentrated seawater outlet of the final-stage flash chamber of the multi-stage flash heat discharge section 4, and the mixed concentrated seawater outlet of the drawing liquid water tank 7 is communicated with the inlet of the water turbine 9; the inlet of the raw material liquid water tank 8 is communicated with an external pretreated seawater source, and the outlet of the raw material liquid water tank 8 is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multi-stage flash evaporation heat discharge section 4; the water turbine 9 is connected with the generator 10 and is suitable for driving the generator 10 to generate electricity; the drawing liquid water tank 7 is communicated with the raw material liquid water tank 8, and the concentrated seawater in the drawing liquid water tank 7 can absorb fresh water in the feed seawater in the raw material liquid water tank 8 to form mixed concentrated seawater and drive the generator 10 to generate electricity through the water turbine 9.
The water and electricity cogeneration system integrates the multi-stage flash evaporation sea water desalination system and the salt difference energy power generation system, takes the concentrated sea water discharged by the multi-stage flash evaporation sea water desalination system as the drawing liquid, and takes the feed sea water as the raw material liquid to generate power, thereby reducing the concentration of the discharged concentrated sea water and reducing the influence of the discharged concentrated sea water on the environment; compared with the traditional salt difference energy power generation system, the osmotic pressure difference between the drawing liquid and the raw material liquid can be improved, and the power generation efficiency is higher; in addition, the salt difference energy power generation system can convert chemical potential energy of water into electric energy, and improves energy utilization efficiency and economic benefit.
The multistage flash evaporation seawater desalination system further comprises a first water pump 1 and a seawater pretreatment device 2; the seawater inlet of the seawater pretreatment device 2 is communicated with the feed seawater, the seawater outlet of the seawater pretreatment device 2 comprises two branches, one branch is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multi-stage flash evaporation heat discharge section 4, and the other branch is communicated with the inlet of the raw material liquid water tank 8; the first water pump 1 is arranged on a pipeline on the seawater inlet side of the seawater pretreatment device 2.
The multistage flash evaporation seawater desalination system further comprises an air extractor 18, and the upper parts of the flash chambers of each stage of the multistage flash evaporation heat discharge section 4 and the multistage flash evaporation heat recovery section 3 are communicated with the air extractor 18 and are suitable for extracting air dissolved in seawater through the air extractor 18.
The water and electricity cogeneration system further comprises a heater 16, wherein a seawater inlet of the heater 16 is communicated with a cooling water outlet of a first-stage flash chamber of the multi-stage flash heat recovery section 3, and a seawater outlet of the heater 16 is communicated with a flash seawater inlet of the first-stage flash chamber of the multi-stage flash heat recovery section 3; the warm side inlet of the heater 16 is adapted to communicate with an external steam turbine set steam extraction port.
Wherein, the cogeneration system also comprises a heat storage system, at least comprising a heat storage heat exchanger 11 and a heat storage device 12; the low-temperature heat source end outlet of the heat storage heat exchanger 11 is communicated with the heat storage medium inlet of the heat storage device 12, and the low-temperature heat source end inlet of the heat storage heat exchanger 11 is communicated with the heat storage medium outlet of the heat storage device 12; the low-temperature heat source end inlet of the heat storage device 12 is communicated with the fresh water outlet of the final-stage flash chamber of the multi-stage flash heat discharge section 4, and the low-temperature heat source end outlet of the heat storage device 12 is connected with the hot end inlet of the heater 16; the heat source end steam inlet of the heat storage heat exchanger 11 is suitable for being connected with an external steam extraction port of the steam turbine unit; a valve number I13 is arranged on a pipeline between the heat storage device 12 and the heater 16; a valve No. two 14 is arranged on a pipeline between the heater 16 and an external steam extraction port of the steam turbine unit; a valve number three 15 is arranged on the pipeline between the heat storage heat exchanger 11 and the steam extraction port of the external turbine unit.
Specifically, a seawater outlet of the seawater pretreatment device 2 in the cogeneration system is communicated with a final-stage flash chamber cooling water inlet of the multi-stage flash heat discharge section 4, a first-stage flash chamber cooling water outlet of the multi-stage flash heat discharge section 4 is divided into two paths, one path returns to the sea, and the other path is communicated with a final-stage flash chamber flash seawater inlet of the multi-stage flash heat discharge section 4. The final stage flash chamber flash evaporation seawater outlet of the multi-stage flash evaporation heat discharge section 4 is communicated with the final stage flash evaporation chamber cooling water inlet of the multi-stage flash evaporation heat recovery section 3, and the first stage flash evaporation chamber cooling water outlet of the multi-stage flash evaporation heat discharge section 4 is communicated with the seawater inlet of the heater 16. The seawater outlet of the heater 16 is communicated with the flash seawater inlet of the first-stage flash chamber of the multi-stage flash heat recovery section 3. The final stage flash chamber flash seawater outlet of the multi-stage flash heat recovery section 3 is communicated with the first stage flash chamber flash seawater inlet of the multi-stage flash heat discharge section 4. The fresh water outlet of the final stage flash chamber of the multi-stage flash heat recovery section 3 is communicated with the fresh water inlet of the first stage flash chamber of the multi-stage flash heat discharge section 4. The warm side inlet of the heater 16 is connected to a steam extraction port in the external turbine train that matches the steam parameter requirements.
The concentrated seawater outlet of the final stage flash chamber of the multi-stage flash evaporation heat discharge section 4 is communicated with the inlet of a drawing liquid water tank 7, and the mixed concentrated seawater outlet of the drawing liquid water tank 7 is communicated with the inlet of a water turbine 9; the sea water outlet of the sea water pretreatment device 2 is communicated with the inlet of the raw material liquid water tank 8.
The heat storage medium inlet of the heat storage device 12 is connected with the low-temperature heat source end outlet of the heat storage heat exchanger 11, and the heat storage medium outlet of the heat storage device 12 is connected with the low-temperature heat source end inlet of the heat storage heat exchanger 11. The fresh water outlet of the final stage flash chamber of the multi-stage flash heat discharge section 4 is connected with the low-temperature heat source end inlet of the heat storage device 12 through a pipeline. The low temperature heat source side outlet of the thermal storage device 12 is connected to the hot side inlet of the heater 16 by a pipe.
The heat source end steam inlet of the heat storage heat exchanger 11 is connected with the steam extraction port of the external turbine set through a pipeline.
A first valve 13 is arranged on a connecting pipeline between the heat storage device 12 and the heater 16; a third valve 15 is arranged on a connecting pipeline between the heat storage heat exchanger 11 and the steam extraction port of the external turbine unit; a second valve 14 is arranged on a connecting pipeline between the heater 16 and a steam extraction port of the external turbine unit; a fourth valve 17 is arranged on the connecting pipeline of the seawater pretreatment device 2 and the raw material liquid water tank 8.
The steam from heater 16 originates from a steam extraction port in thermal storage device 12 or an external turbine set that matches the steam parameter requirements.
The flash chamber number of stages of the multi-stage flash heat recovery section 3 may be not less than five stages; the flash chamber number of the multi-stage flash heat discharge section 4 may be not less than three.
A first water pump 1 is arranged on a communication pipeline of the feed seawater and the seawater inlet of the seawater pretreatment device 2; a second water pump 5 is arranged on a fresh water outlet pipeline of a final-stage flash chamber of the multi-stage flash heat discharge section 4; a third water pump 6 is arranged on a communication pipeline between the multistage flash evaporation heat discharge section 4 and the drawing liquid water tank 7;
the upper parts of the flash chambers of the multi-stage flash heat discharge section 4 and the multi-stage flash heat recovery section 3 are communicated with an air extractor 18 for extracting air dissolved in seawater, so as to ensure the stable low-pressure environment of each flash chamber.
The salt difference energy utilization method in the salt difference energy power generation system is a osmotic pressure energy method.
In another embodiment, a method for operating a cogeneration system is provided, including the cogeneration system described above, where the specific operating method is as follows: enabling the concentrated seawater discharged by the multistage flash evaporation seawater desalination system to flow into a drawing liquid water tank 7; the feed seawater enters a raw material liquid water tank 8, and the concentrated seawater in a drawing liquid water tank 7 is changed into mixed concentrated seawater after absorbing fresh water in the feed seawater in the raw material liquid water tank 8 by utilizing the osmotic pressure principle; the mixed concentrated seawater is utilized to drive the water turbine 9 to rotate through the water pipe, so as to drive the generator 10 to generate electricity.
Wherein, the feed seawater after absorbing water in the raw material liquid water tank 8 is mixed with the outlet seawater of the seawater pretreatment device 2 and then enters a multistage flash evaporation seawater desalination system for recycling.
When the external turbine unit does not participate in peak shaving, the valve number three 15 and the valve number two 14 are opened, and the valve number one 13 is closed; allowing the extracted steam of the external turbine unit to enter the heat storage heat exchanger 11 for releasing heat so as to store heat in the heat storage device 12; the steam extracted from the external turbine unit is led to the heater 16 to release heat so as to drive the multistage flash evaporation sea water desalination system to operate.
When the external turbine unit participates in peak shaving, the valve number three 15 and the valve number two 14 are closed, and the valve number one 13 is opened; the heat stored by the heat storage device 12 is utilized to drive the multi-stage flash evaporation sea water desalination system to operate.
Wherein, when the multistage flash evaporation sea water desalination system desalinates sea water, concretely include: pumping the pretreated sea water into a condensation tube bundle at the upper part of a final-stage flash chamber of a multi-stage flash heat discharge section 4, exchanging heat with flash steam in the flash chamber step by step, and condensing the flash steam in the flash chamber into fresh water while preheating the sea water; after the feed seawater is preheated by the multi-stage flash heat discharge section 4, the feed seawater is split into two parts, one part returns to the sea, and the other part is mixed with circulating seawater in a final stage flash chamber of the multi-stage flash heat discharge section 4; the mixed circulating seawater is pumped into a condensation tube bundle of a final stage flash chamber of the multi-stage flash heat recovery section 3, flows into a first stage flash chamber of the multi-stage flash heat recovery section 3 along the flow direction opposite to the flow direction of the flash seawater as cooling water of flash steam, then flows into a heater 16 to be further heated, flows into the lower part of the first stage flash chamber of the multi-stage flash heat recovery section 3 to start flash evaporation, the evaporated steam is condensed into fresh water, the flash seawater flows out of the final stage flash chamber of the multi-stage flash heat recovery section 3 and then enters the first stage flash chamber of the multi-stage flash heat discharge section 4 to continue flash evaporation until the final stage flash chamber of the multi-stage flash heat discharge section 4 discharges concentrated seawater, and the fresh water is collected.
Specifically, the operation method for preparing fresh water comprises the following steps: all the pretreated seawater is pumped into a condensation tube bundle at the upper part of a final-stage flash chamber of the multi-stage flash heat discharge section 4, heat exchange is carried out step by step with flash steam in the flash chamber, and the steam flash-evaporated in the flash chamber is condensed into fresh water while being preheated. After the feed seawater is preheated in the multi-stage flash heat discharge section 4, the feed seawater is split into two parts, one part returns to the sea, and the other part is mixed with the circulating seawater. The mixed seawater is pumped into a condensation tube bundle of a final stage flash chamber of the multi-stage flash heat recovery section 3, flows to a first stage flash chamber as cooling water of flash steam along the flow direction opposite to the flash seawater, flows out of the first stage flash chamber, flows into a heater 16 to be further heated, flows into the lower part of the first stage flash chamber of the multi-stage flash heat recovery section 3 at the highest temperature to start flash evaporation, the evaporated steam is condensed into fresh water, and the flash seawater flows out of the final stage flash chamber of the multi-stage flash heat recovery section 3 and then enters the first stage flash chamber of the multi-stage flash heat discharge section 4 to continue flash evaporation until the final stage discharges concentrated seawater, and the fresh water is collected.
The operation method for generating electricity by using the salt difference energy comprises the following steps: the concentrated seawater discharged by the multistage flash evaporation seawater desalination system flows into a drawing liquid water tank 7 through a third water pump 6, part of pretreated feed seawater enters a raw material liquid water tank 8 from the top, the concentrated seawater absorbs fresh water in the feed seawater by utilizing the osmotic pressure principle and becomes mixed concentrated seawater, and the mixed concentrated seawater drives a water turbine 9 to rotate through a water pipe so as to drive a generator 10 to generate electricity. The feed seawater which is absorbed with water and heated flows out from the bottom of the raw material liquid water tank 8, is mixed with the outlet seawater of the seawater pretreatment device 2, and enters a multistage flash evaporation seawater desalination system for recycling.
The peak shaving operation method comprises the following steps: when the external turbine unit does not participate in peak shaving, the valve number three 15 and the valve number two 14 are opened, the valve number one 13 is closed, the extracted steam from the turbine unit enters the heat storage heat exchanger 11 to release heat, the heat storage device 12 stores heat, the extracted steam from the turbine unit enters the heater 16 to release heat, the multistage flash evaporation sea water desalination system operates under the driving of the extracted steam of the turbine, and the salt difference energy power generation system operates normally; when the unit participates in peak shaving, no steam is provided, the valve No. 15 and the valve No. 14 are closed at the moment, the valve No. 13 is opened, and the heat stored by the heat storage device 12 can drive the normal operation of the multistage flash evaporation sea water desalination system and the salt difference energy power generation system.
In summary, the cogeneration system and the operation method integrate the multi-stage flash evaporation sea water desalination system and the salt-difference energy power generation system together, take concentrated sea water discharged by the multi-stage flash evaporation sea water desalination system as a drawing liquid and feed sea water as a raw material liquid, and compared with the traditional salt-difference energy power generation system, the osmotic pressure difference is improved, the power generation efficiency is improved, and the salt-difference energy power generation system converts chemical potential energy of water into electric energy, thereby improving the energy utilization efficiency and economic benefit.
According to the cogeneration system and the operation method, the cogeneration system is coupled with the heat storage device, so that the fresh water supply requirement is ensured while the peak regulation requirement of the power grid is met, and the operation flexibility of the system is improved.
The cogeneration system and the operation method reduce the concentration of the concentrated seawater discharged by the multistage flash evaporation seawater desalination system, reduce the influence on the environment, and have good social benefits.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.
Claims (10)
1. A cogeneration system, comprising:
the multistage flash evaporation sea water desalination system at least comprises a multistage flash evaporation heat recovery section and a multistage flash evaporation heat discharge section which are connected;
the salt difference energy power generation system at least comprises a drawing liquid water tank, a raw material liquid water tank, a water turbine and a power generator;
an inlet of the drawing liquid water tank is communicated with a concentrated seawater outlet of a final-stage flash chamber of the multistage flash evaporation heat discharge section, and a mixed concentrated seawater outlet of the drawing liquid water tank is communicated with an inlet of the water turbine;
the inlet of the raw material liquid water tank is communicated with an external pretreated seawater source, and the outlet of the raw material liquid water tank is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multistage flash evaporation heat discharge section;
the water turbine is connected with the generator and is suitable for driving the generator to generate electricity;
the liquid drawing water tank is communicated with the raw material liquid water tank, and concentrated seawater in the liquid drawing water tank can absorb fresh water in the feed seawater in the raw material liquid water tank to form mixed concentrated seawater and drive the generator to generate electricity through the water turbine.
2. A cogeneration system according to claim 1, wherein,
the multistage flash evaporation seawater desalination system further comprises a first water pump and a seawater pretreatment device;
the seawater inlet of the seawater pretreatment device is communicated with the feed seawater, the seawater outlet of the seawater pretreatment device comprises two branches, one branch is communicated with the cooling water inlet of the final-stage flash evaporation chamber of the multistage flash evaporation heat discharge section, and the other branch is communicated with the inlet of the raw material liquid tank;
the first water pump is arranged on a pipeline at the sea water inlet side of the sea water pretreatment device.
3. A cogeneration system according to claim 1, wherein,
the multistage flash evaporation seawater desalination system further comprises an air extractor, wherein the upper parts of the flash chambers of each stage of the multistage flash evaporation heat discharge section and the multistage flash evaporation heat recovery section are communicated with the air extractor, and the air extractor is suitable for extracting air dissolved in seawater.
4. A cogeneration system according to any one of claims 1-3, wherein,
the system also comprises a heater, wherein a seawater inlet of the heater is communicated with a cooling water outlet of a first-stage flash chamber of the multi-stage flash heat recovery section, and a seawater outlet of the heater is communicated with a flash seawater inlet of the first-stage flash chamber of the multi-stage flash heat recovery section;
the hot side inlet of the heater is suitable for being communicated with an external steam extraction port of the turbine unit.
5. A cogeneration system according to claim 4, wherein,
the system also comprises a heat storage system, at least comprising a heat storage heat exchanger and a heat storage device;
the low-temperature heat source end outlet of the heat storage heat exchanger is communicated with the heat storage medium inlet of the heat storage device, and the low-temperature heat source end inlet of the heat storage heat exchanger is communicated with the heat storage medium outlet of the heat storage device;
the low-temperature heat source end inlet of the heat storage device is communicated with the fresh water outlet of the final-stage flash chamber of the multi-stage flash heat discharge section, and the low-temperature heat source end outlet of the heat storage device is connected with the hot end inlet of the heater;
the heat source end steam inlet of the heat storage heat exchanger is suitable for being connected with an external steam extraction port of the steam turbine unit;
a first valve is arranged on a pipeline between the heat storage device and the heater;
a second valve is arranged on a pipeline between the heater and an external steam extraction port of the steam turbine unit;
and a valve III is arranged on a pipeline between the heat storage heat exchanger and the steam extraction port of the external turbine unit.
6. A method of operating a cogeneration system comprising a cogeneration system according to any one of claims 1 to 5, the method comprising:
enabling the concentrated seawater discharged by the multistage flash evaporation seawater desalination system to flow into a liquid drawing water tank;
the feed seawater enters a raw material liquid water tank, and the concentrated seawater in a drawing liquid water tank is changed into mixed concentrated seawater after absorbing fresh water in the feed seawater in the raw material liquid water tank by utilizing the osmotic pressure principle;
the mixed concentrated seawater is utilized to drive the water turbine to rotate through the water pipe, so that the generator is driven to generate electricity.
7. A method of operating a cogeneration system according to claim 6, wherein,
the feed seawater after absorbing water in the raw material liquid water tank is mixed with the outlet seawater of the seawater pretreatment device and then enters a multistage flash evaporation seawater desalination system for recycling.
8. A method of operating a cogeneration system according to claim 6, wherein,
when the external turbine unit does not participate in peak shaving, the third valve and the second valve are opened, and the first valve is closed;
leading the extracted steam of the external turbine unit to enter a heat storage heat exchanger for heat release so as to enable the heat storage device to store heat;
the steam extracted from the external turbine unit enters a heater to release heat so as to drive the multistage flash evaporation sea water desalination system to operate.
9. A method of operating a cogeneration system according to claim 6, wherein,
when the external turbine unit participates in peak shaving, the third valve and the second valve are closed, and the first valve is opened;
the heat stored by the heat storage device is utilized to drive the multistage flash evaporation sea water desalination system to operate.
10. A method of operating a cogeneration system according to any one of claims 6-9, wherein,
the multi-stage flash evaporation sea water desalination system specifically comprises:
pumping the pretreated sea water into a condensation tube bundle at the upper part of a final-stage flash chamber of a multi-stage flash heat discharge section, exchanging heat with flash steam in the flash chamber step by step, and condensing the flash steam in the flash chamber into fresh water while preheating the sea water;
after being preheated by the multi-stage flash evaporation heat discharge section, the feed seawater is split into two parts, one part returns to the sea, and the other part is mixed with circulating seawater in a final stage flash evaporation chamber of the multi-stage flash evaporation heat discharge section;
the mixed circulating seawater is pumped into a condensation tube bundle of a final stage flash chamber of the multi-stage flash heat recovery section, flows into a heater to be further heated along the flow direction opposite to the flow direction of the flash seawater as cooling water of the flash steam into a first stage flash chamber of the multi-stage flash heat recovery section, flows into the lower part of the first stage flash chamber of the multi-stage flash heat recovery section to start flash evaporation, the evaporated steam is condensed into fresh water, and the flash seawater flows out of the final stage flash chamber of the multi-stage flash heat recovery section and enters the first stage flash chamber of the multi-stage flash heat discharge section to continue flash evaporation until the final stage flash chamber of the multi-stage flash heat discharge section discharges concentrated seawater, and the fresh water is collected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310180239.0A CN116332268A (en) | 2023-02-17 | 2023-02-17 | Water-electricity cogeneration system and operation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310180239.0A CN116332268A (en) | 2023-02-17 | 2023-02-17 | Water-electricity cogeneration system and operation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116332268A true CN116332268A (en) | 2023-06-27 |
Family
ID=86884943
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310180239.0A Pending CN116332268A (en) | 2023-02-17 | 2023-02-17 | Water-electricity cogeneration system and operation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116332268A (en) |
-
2023
- 2023-02-17 CN CN202310180239.0A patent/CN116332268A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5462939B2 (en) | Power generation and seawater desalination complex plant | |
| CN101737282B (en) | High-efficiency hybrid ocean temperature difference power generating system | |
| JP5331890B2 (en) | Cogeneration plant and biomass reforming combined power plant | |
| CN101806445B (en) | Trough type solar multistage heat utilization device | |
| CN109336206A (en) | A kind of hydro-thermal cogeneration system for supporting fuel cell Sewage treatment and sea water desalination | |
| AU2005284554A1 (en) | Seawater desalination plant | |
| CN110500808A (en) | Electric cold supply system | |
| CN104405600A (en) | Solar energy and ocean temperature difference energy cascading type power generation device and utilization method thereof | |
| US7827792B2 (en) | Refrigerant cooled main steam condenser binary cycle | |
| CN114109751A (en) | Thermoelectric energy power generation and comprehensive utilization system | |
| CN101498438A (en) | Condensed water reclaiming system | |
| CN201680347U (en) | Slot type solar multi-stage thermal utilization device | |
| CN116332268A (en) | Water-electricity cogeneration system and operation method | |
| CN115405390A (en) | Pressurized water reactor power generation, energy storage, seawater desalination and refrigeration coupled operation system and method | |
| CN115126563A (en) | Frequency modulation system with heat pump and steam ejector and working method | |
| WO2023023691A1 (en) | A process and system for producing hydrogen | |
| CN210764426U (en) | Pure water preparation system of ejector driven membrane distillation | |
| CN115417467B (en) | Water-heat cogeneration system based on heat storage device and operation method | |
| CN220849930U (en) | Vacuum pumping system applied to condensing steam turbine | |
| CN217236214U (en) | Low-energy-consumption and water-saving seawater-fresh water combined circulating cooling system | |
| CN112302745B (en) | Green heat pump refrigerating and heating device applied to turbine work | |
| CN116085085A (en) | Peak regulating system and method for coal-fired power plant | |
| US11759725B1 (en) | Multistage flash desalination system | |
| CN215809432U (en) | Waste heat recovery utilizes device in concentrated nitric acid production | |
| CN219283302U (en) | Periodic sewage heat recovery device for drum boiler |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |