Combined condenser for recovering dead steam heat energy of condensing steam turbine
The combined condenser classifies the exhaust gas, uses the steam injection and steam extraction and hybrid condenser to improve the heat recovery, and solves the problem of exhaust gas heat discharge loss in the condenser thermal power generator set, and achieves the improvement of thermal efficiency and environmentally friendly effects.
Patent Information
- Application Number
- CN202421046167.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-14
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-14
AI Technical Summary
The heat energy discharge loss of steam in condensation thermal generator sets is the largest, resulting in energy waste and thermal pollution. The existing technology needs to directly emit steam and heat energy in non-heating seasons, affecting thermal efficiency and environmental protection.
Design a combined condenser, and use a steam injection and exhaust to divide exhaust into two levels: high pressure and low pressure. The low pressure exhaust to condense in the surface condenser, and the high pressure exhaust to condense in the mixed condenser. The condensed water of the surface condenser is used as the cooling water of the mixed condenser to improve the heat energy recovery efficiency.
Effectively recover the heat energy of exhausted steam, improve the thermal efficiency of the turbine, reduce thermal pollution, replace some low-pressure heaters, and reduce production costs.
Smart Images
Figure CN222257782U_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of energy conservation and emission reduction of thermal power generating sets, and specifically relates to a combined condenser for recovering the heat energy of exhaust steam of a condensing steam turbine. Background Art
[0002] Condensing steam-fired power generation is one of the main power generation methods in the power supply industry. The thermal cycle of a condensing steam-fired power generator is that when the fuel is burned in the boiler, chemical energy is converted into thermal energy, and the thermal energy is absorbed by the working fluid water and becomes water vapor; when the high-temperature and high-pressure steam flows through the turbine, it drives the turbine to rotate and do work, converting part of the thermal energy into mechanical energy. After doing work, the exhaust steam enters the condenser and transfers the remaining thermal energy to the cooling water or cooling air as a refrigerant. The exhaust steam condenses into water and is sent back to the boiler to regain thermal energy, completing a cycle, and repeating the cycle to keep the heat-work conversion going. In the above complex thermal cycle process, there are a lot of heat losses in various links, among which the heat loss of boiler equipment is 6-10%, the heat loss of pipelines is 1%, and the heat loss of exhaust steam is 46-60%. From this, we can see that the heat loss of the exhaust steam part is the largest. If you want to improve the thermal efficiency of a condensing steam power plant, the heat recovery of exhaust steam is the most direct means.
[0003] In the prior art, the most important means of recovering the heat energy of exhaust steam is to use it for the heat output of the urban heating network. However, it is greatly affected by distance and season. In the non-heating season, the exhaust steam still needs to be directly discharged and the heat energy in the exhaust steam is transferred to the surrounding environment, resulting in huge energy waste and thermal pollution. Therefore, how to reduce the heat loss of exhaust steam and improve the thermal efficiency of condensing steam thermal power generator sets is the focus of research by those skilled in the art. Summary of the invention
[0004] The utility model aims to provide a combined condenser for recovering the heat energy of exhaust steam from a condensing steam turbine. The condenser utilizes the pressure-increasing characteristics of a steam ejector to divide the exhaust steam from the steam turbine into two levels, high pressure and low pressure. The low pressure exhaust steam is condensed in a surface condenser, and the heat energy of the exhaust steam is discharged into the surrounding environment; the high pressure exhaust steam is condensed in a hybrid condenser, and the condensate from the surface condenser is used as cooling water for the hybrid condenser, so that the heat energy of the high pressure exhaust steam is absorbed and utilized.
[0005] To achieve the above-mentioned purpose, the technical scheme of the utility model is a combined condenser for recovering the heat energy of exhaust steam from a condensing steam turbine, which is installed in a condensing thermal power generator system. The condensing thermal power generator system includes a boiler system, a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, a condenser, a deaerator, a high-pressure heater, a cooling tower, and a condenser hot water well. The main steam pipeline is connected to the outlet of the superheater of the boiler system and the inlet of the high-pressure cylinder. The cold reheating section pipeline is connected to the exhaust port of the high-pressure cylinder and the inlet of the reheater of the boiler system. The hot reheating section pipeline is connected to the outlet of the reheater and the inlet of the intermediate-pressure cylinder; the intermediate- and low-pressure cylinder connecting pipelines are connected to the exhaust port of the intermediate-pressure cylinder and the inlet of the low-pressure cylinder; the deaerator is connected to the high-pressure heater through a feedwater pump pipeline, and the outlet pipeline of the high-pressure heater is connected to the boiler system; the intermediate-pressure cylinder extraction pipeline is connected to the high-pressure heater and the intermediate-pressure cylinder for heating feedwater; the drain outlet of the high-pressure heater is connected to the deaerator,
[0006] The combined condenser includes a surface condenser, a jet steam extractor, and a mixed condenser. The exhaust steam pipe at the inlet of the surface condenser is connected to the exhaust port of the low-pressure cylinder and the inlet of the surface condenser, and the condensate pump pipe is connected to the condenser hot water well and the nozzle of the mixed condenser; the circulating cooling water pump pipe is connected to the cooling tower water pool and the cooling water inlet of the surface condenser, and the cooling water outlet pipe of the surface condenser is connected to the cooling water outlet of the surface condenser and the cooling water inlet of the cooling tower; the working steam pipe of the jet steam extractor is connected to the steam extraction port of the turbine and the working steam inlet of the jet steam extractor, and the steam outlet of the jet steam extractor is connected to the steam inlet pipe of the mixed condenser; the induced steam pipe of the jet steam extractor is connected to the inlet of the surface condenser and the induced steam inlet of the jet steam extractor; the drain pump pipe is connected to the drain outlet of the mixed condenser and the water inlet of the deaerator.
[0007] The mixed condenser is connected to the surface condenser and is provided with a vacuum extraction pipeline.
[0008] A shut-off valve is arranged on the condensate pump pipeline.
[0009] A shut-off valve is arranged on the drain pipe.
[0010] The condensate pump pipeline is connected with the drain pipeline, and a shut-off valve is arranged on the connecting pipeline.
[0011] It also includes a water jet steam extractor, which is installed on the condensate pump pipeline, the condensate pipeline is connected to the working water flow inlet of the water jet steam extractor, the induced steam pipe of the water jet steam extractor is connected to the outlet of the surface condenser, and the outlet of the water jet steam extractor is connected to the nozzle of the mixed condenser.
[0012] The combined condenser of the utility model, the hybrid condenser and the surface condenser are high- and low-pressure two-stage condensers. The inlet pressure of the surface condenser is relatively low, which is the exhaust steam pressure of the turbine; the inlet pressure of the hybrid condenser is relatively high, which is the pressure of the exhaust steam after being boosted by the steam ejector. Since there is a pressure difference between the hybrid condenser and the surface condenser, the insulation temperatures of the two are also different, so that the condensate of the surface condenser can serve as cooling water for the hybrid condenser, and at the same time solves the problem of high requirements for cooling water of the hybrid condenser, and further reduces the production cost.
[0013] The utility model combined condenser can effectively recover the heat energy in the exhaust steam and significantly improve the thermal efficiency of the steam turbine; after adopting the condenser of the present application, part of the low-pressure heater can be replaced, the condensate system can be simplified, and the cost can be greatly reduced; after the heat energy of part of the exhaust steam is utilized, the thermal pollution of the surrounding environment is reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 The figure is a simplified diagram of the thermal system of a condensing steam thermal power unit in the prior art.
[0015] Figure 2 The utility model is a simplified diagram of the thermal system implemented.
[0016] Figure 3 is a schematic diagram of the combined condenser structure.
[0017] Figure 4 This is a schematic diagram of the structure of the steam ejector. DETAILED DESCRIPTION
[0018] Example 1
[0019] like Figure 1It is a thermal system of a condensing steam-fired power unit in the prior art, including a high-pressure cylinder 1, a reheater 14, an intermediate-pressure cylinder 2, a low-pressure cylinder 3, a condenser 5, four low-pressure heaters 7, a deaerator 8, a high-pressure heater 10, an economizer 11, a water-cooled wall 12, and a superheater 13. The reheat cold section pipeline is connected to the reheater inlet, the reheat hot section pipeline is connected to the intermediate-pressure cylinder inlet, the intermediate-pressure cylinder and the low-pressure cylinder connecting pipeline is connected to the low-pressure cylinder inlet, the low-pressure cylinder exhaust pipeline is connected to the condenser, and the condensate outlet of the condenser is connected to the condenser. The feed water pump pipeline is connected to the low-pressure heater, the low-pressure heater pipeline is connected to the deaerator, the deaerator is connected to the high-pressure heater through the feed water pump pipeline, and the high-pressure heater is connected to the economizer, water wall, and superheater in sequence. Among them, the medium-pressure cylinder extraction pipeline and the low-pressure cylinder extraction pipeline are respectively connected to the high-pressure heater and the low-pressure heater for heating feed water and condensate. The drain outlet of the high-pressure heater is connected to the deaerator, and the drain outlet of the low-pressure heater is connected to the condenser. The circulating cooling water pump 16 pipeline is connected to the cooling The cooling tower 15 is connected to the circulating cooling water inlet of the condenser 5, and the circulating cooling water outlet pipe of the condenser 5 is connected to the circulating cooling water inlet of the cooling tower. The specific working process is that the main steam after absorbing heat from the boiler expands and works in the high-pressure cylinder 1 and returns to the reheater 14 to be heated again into reheated steam. The reheated steam expands and works in the medium-pressure cylinder 2 and enters the low-pressure cylinder 3 to continue to expand and work. The exhaust steam after the expansion and work of the low-pressure cylinder 3 is discharged into the condenser 5. The circulating cooling water absorbs the heat energy of the exhaust steam and the exhaust steam condenses into condensed water. In this process, the circulating cooling water transfers the absorbed heat energy to the surrounding environment through the cooling tower 15, causing huge waste and environmental pollution, and is also the biggest cause of heat loss. The condensed water is boosted by the condensate pump 6 and heated by the low-pressure heater 7 and then sent to the deaerator 8 for deoxygenation. The deoxygenated water is boosted by the feed water pump 9 and heated by the high-pressure heater 10 and then passes through the economizer 11, the water-cooled wall 12, and the superheater 13 in sequence to become superheated steam for the next steam-water cycle.
[0020] In this embodiment, a combined condenser for recovering the exhaust steam heat energy of a condensing steam turbine is installed in a condensing thermal power generating unit system. Figure 2 , 3As shown, the condenser 5 and four low-pressure heaters 7 in the above system are replaced. The combined condenser includes a surface condenser 5, a steam ejector 17, and a mixed condenser 18. The exhaust steam pipeline at the inlet of the surface condenser is connected to the exhaust port of the low-pressure cylinder 3 and the inlet of the surface condenser 5. The condensate pump pipeline is connected to the condenser hot water well and the mixed condenser nozzle 21; the circulating cooling water pump pipeline is connected to the cooling tower pool and the circulating cooling water inlet of the surface condenser 5. The circulating cooling water outlet pipeline of the surface condenser It is connected to the circulating cooling water outlet of the surface condenser and the circulating cooling water inlet of the cooling tower; the working steam pipeline of the steam jet extractor 17 is connected to the steam extraction port of the steam turbine and the working steam inlet of the steam jet extractor, and the steam outlet of the steam jet extractor 17 is connected to the steam inlet pipeline of the hybrid condenser; the induced steam pipeline of the steam jet extractor 17 is connected to the inlet of the surface condenser and the induced steam inlet of the steam jet extractor; the drain pump pipeline is connected to the drain outlet of the hybrid condenser 18 and the water inlet of the deaerator 8. The hybrid condenser is connected to the surface condenser with a vacuum extraction pipeline, and a shut-off valve is provided on the condensate pump pipeline; a shut-off valve is provided on the drain pipeline; the condensate pump pipeline is connected to the drain pipeline, and a shut-off valve is provided on the connecting pipeline.
[0021] The surface condenser is a tubular heat exchanger, with circulating cooling water in the tube side and exhaust steam in the shell side. The exhaust steam in the shell side transfers the latent heat to the circulating cooling water in the tube side through the tube bundle and then condenses into condensed water. The circulating cooling water transfers the heat energy it carries to the surrounding environment. The function of the surface condenser is to condense the exhaust steam entering the surface condenser into condensed water, which serves as cooling water for the mixed condenser and creates conditions for the normal operation of the mixed condenser. The steam ejector extractor uses its characteristics of ejection, boosting and heating to extract part of the exhaust steam of the condensing steam turbine and increase the pressure and temperature of the extracted exhaust steam. The outlet pressure of the steam ejector extractor is about twice the ejection steam pressure. This value is determined by the boosting characteristics of the extractor. Different extractors have different values to ensure that the steam pressure entering the mixed condenser is high, creating conditions for the normal operation of the mixed condenser. The mixed condenser is a closed container. Steam from the jet steam extractor outlet enters from the top, and cooling water is sprayed in from the nozzle to directly contact the steam for heat exchange. The steam releases latent heat and condenses into water, which is mixed with cooling water to form a drain. The heat energy of the exhaust steam is stored in the drain. The function of the mixed condenser is to recover the heat energy of the exhaust steam entering the jet steam extractor. The more exhaust steam enters the jet steam extractor, the more heat energy is recovered. The function of the pump and pipeline is to ensure the orderly flow of condensate and drain. The function of the valve is to switch during the start and stop of the unit. The function of the vacuum pipe between the mixed condenser and the surface condenser is to discharge the non-condensable gas in the mixed condenser to the surface condenser and then discharge it away. One jet steam extractor and one mixed condenser in this scheme can replace four low-pressure heaters, and there is only one extraction port, which is lower in cost.
[0022] The thermal system of condensing thermal power units using combined condensers can effectively recover the heat energy of exhaust steam, improve the cycle thermal efficiency, and reduce thermal pollution. Figure 2 The main steam after absorbing heat from the boiler expands and does work in the high-pressure cylinder 1 and then returns to the reheater 14 to be heated again into reheated steam. The reheated steam expands and does work in the intermediate-pressure cylinder 2 and then enters the low-pressure cylinder 3 to continue expanding and doing work. The exhaust steam after the expansion and work of the low-pressure cylinder 3 is discharged into the combined condenser. Specifically, the exhaust steam entering the combined condenser is divided into two paths, one path enters the surface condenser, and the other path enters the steam ejector. The exhaust steam entering the surface condenser transfers latent heat to the circulating cooling water and then condenses into condensate. The circulating cooling water uses the cooling tower to transfer heat energy to the surrounding environment. The condensate is pumped by the condensate pump through the pipeline to the nozzle of the mixed condenser to serve as cooling water for the mixed condenser; the exhaust steam entering the jet steam extractor on the other hand is ejected by the working steam of the jet steam extractor to become mixed steam. The temperature and pressure of the mixed steam are higher than those of the exhaust steam. The mixed steam enters the mixed condenser from the outlet of the jet steam extractor and mixes with the cooling water ejected from the nozzle of the mixed condenser. The mixed steam transfers latent heat to the cooling water and then condenses into water. After mixing with the cooling water, it forms a drain. The heat energy of the exhaust steam entering the jet steam extractor is stored in the drain for recycling. The function of the vacuum pipe is to discharge the non-condensable gas in the mixed condenser to the surface condenser and then discharge it away. The drain water is pressurized by the drain pump 16 and sent to the deaerator 8 for deoxygenation. The deoxygenated water is pressurized by the feed water pump 9 and heated by the high-pressure heater 10. It passes through the economizer 11, the water-cooled wall 12, and the superheater 13 in sequence to become superheated steam for the next steam-water cycle.
[0023] Example 2
[0024] On the basis of Example 1, a water jet extractor can be set on the condensate pump pipeline, the condensate pipeline is connected to the working water flow inlet of the water jet extractor, the induced steam pipe of the water jet extractor is connected to the inlet of the surface condenser, and the outlet of the water jet extractor is connected to the nozzle of the mixing condenser. Part of the exhaust steam is introduced into the mixing condenser through the water jet extractor, thereby further improving the recovery of the exhaust steam heat energy.
[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. All modifications, equivalent substitutions, improvements, etc. within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A combined condenser for recovering the heat energy of exhaust steam from a condensing steam turbine, installed in a condensing thermal power generator system, the condensing thermal power generator system comprising a boiler system, a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, a condenser, a deaerator, a high-pressure heater, a cooling tower, and a condenser hot water well, wherein a main steam pipeline is connected to the outlet of a superheater of the boiler system and an inlet of a high-pressure cylinder, a cold reheating section pipeline is connected to the exhaust port of the high-pressure cylinder and the inlet of a reheater of the boiler system, and a hot reheating section pipeline is connected to the outlet of the reheater and the inlet of an intermediate-pressure cylinder; intermediate- and low-pressure cylinder connecting pipelines are connected to the exhaust port of the intermediate-pressure cylinder and the inlet of the low-pressure cylinder; the deaerator is connected to the high-pressure heater through a feedwater pump pipeline, and the outlet pipeline of the high-pressure heater is connected to the boiler system; the intermediate-pressure cylinder extraction pipeline is connected to the high-pressure heater and the intermediate-pressure cylinder for heating feedwater; the drain outlet of the high-pressure heater is connected to the deaerator, characterized in that The combined condenser includes a surface condenser, a jet steam extractor, and a mixed condenser. The exhaust steam pipe at the inlet of the surface condenser is connected to the exhaust port of the low-pressure cylinder and the inlet of the surface condenser, and the condensate pump pipe is connected to the condenser hot water well and the nozzle of the mixed condenser; the circulating cooling water pump pipe is connected to the cooling tower water pool and the cooling water inlet of the surface condenser, and the cooling water outlet pipe of the surface condenser is connected to the cooling water outlet of the surface condenser and the cooling water inlet of the cooling tower; the working steam pipe of the jet steam extractor is connected to the steam extraction port of the turbine and the working steam inlet of the jet steam extractor, and the steam outlet of the jet steam extractor is connected to the steam inlet pipe of the mixed condenser; the induced steam pipe of the jet steam extractor is connected to the inlet of the surface condenser and the induced steam inlet of the jet steam extractor; the drain pump pipe is connected to the drain outlet of the mixed condenser and the water inlet of the deaerator.
2. The combined condenser for recovering exhaust steam heat energy of a condensing steam turbine according to claim 1, characterized in that: The mixed condenser is connected to the surface condenser and is provided with a vacuum extraction pipeline.
3. The combined condenser for recovering exhaust steam heat energy from a condensing steam turbine according to claim 1, characterized in that: A shut-off valve is arranged on the condensate pump pipeline.
4. The combined condenser for recovering exhaust steam heat energy of a condensing steam turbine according to claim 1, characterized in that: A shut-off valve is arranged on the drain pump pipeline.
5. The combined condenser for recovering exhaust steam heat energy of a condensing steam turbine according to claim 1, characterized in that: The condensate pump pipeline is connected with the drain pump pipeline, and a shut-off valve is arranged on the connecting pipeline.
6. The combined condenser for recovering exhaust steam heat energy of a condensing steam turbine according to claim 1, characterized in that: The invention also includes a water jet steam extractor, which is installed on the condensate pump pipeline, and the condensate pipeline is connected to the working water flow of the water jet steam extractor. The inlet is connected, the ejector steam pipe of the water ejector is connected to the outlet of the surface condenser, and the outlet of the water ejector is connected to the nozzle of the hybrid condenser.