Deep utilization method of steam condensation water
By using the combined use of primary and secondary heat exchangers and condenser and air preheater in the depth utilization method of steam condensed water, the problem of underutilization of heat from steam condensed water is solved, and the boiler system energy consumption, combustion stability and pollution emission reduction are achieved.
Patent Information
- Application Number
- CN202411641830.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-03-04
AI Technical Summary
The prior art fails to fully utilize the heat of steam condensed water, resulting in high energy consumption of boiler systems, unstable combustion, and pollution emissions.
A deep utilization method is adopted to exchange water and water heat through primary and secondary heat exchangers. Combined with the use of condensers and air preheaters, the heat of steam condensed water is fully utilized to increase the inlet water temperature and combustion air temperature of the boiler system.
It has achieved the reduction of energy consumption in the boiler system, the stability and strengthening of combustion, reduced pollution emissions, and improved the overall efficiency of the system.
Smart Images
Figure CN119554633A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of steam condensate recycling and utilization, and in particular to a method for deep utilization of steam condensate. Background Art
[0002] Steam condensate is water containing energy. During the heating process, only the latent heat of steam is effectively utilized, while the sensible heat of steam is hardly utilized, which accounts for 20% to 30% of the total heat of steam. In addition, the quality of uncontaminated steam condensate is close to pure water, and can be used as high-quality boiler feed water or production process water. Therefore, it is urgent to design a method for deep utilization of steam condensate, which can make full use of steam condensate for heat exchange, increase the water inlet temperature of the boiler system, reduce boiler energy consumption, increase the temperature of the combustion-supporting air, and stabilize and strengthen combustion. Summary of the invention
[0003] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a method for deep utilization of steam condensate, which can fully utilize steam condensate for heat exchange, increase the water inlet temperature of the boiler system, reduce boiler energy consumption; increase the combustion air temperature, stabilize and enhance combustion.
[0004] The object of the present invention is achieved in that: A method for deep utilization of steam condensate, comprising the following steps: The steam condensate enters the primary heat exchanger and exchanges heat with the water generated by the condenser. The water produced after the first-stage heat exchange enters the deaerator, and the steam condensate produced after the first-stage heat exchange enters the second-stage heat exchanger for water-to-water heat exchange; The water generated after the secondary heat exchange enters the condenser to exchange heat with the flue gas, and the steam condensate generated after the secondary heat exchange enters the air preheater to exchange heat with the cold air.
[0005] Preferably, the water generated after the secondary heat exchange enters the condenser and the water temperature rises after heat exchange, preparing for the water-to-water heat exchange in the primary heat exchanger. At the same time, the low-temperature water exchanges heat with the high-temperature flue gas to reduce the high-temperature flue gas to below 60°C. The water vapor in the high-temperature flue gas is condensed when it is cooled, and some harmful substances in the flue gas dissolve in the condensed water.
[0006] Preferably, the steam condensate outlet of the primary heat exchanger is connected to the steam condensate inlet of the secondary heat exchanger, the steam condensate outlet of the secondary heat exchanger is connected to the water inlet of the air preheater, the water outlet of the air preheater is connected to the water supply pipe, the water supply pipe is connected to the water supply inlet of the secondary heat exchanger, the water supply outlet of the secondary heat exchanger is connected to the water inlet of the condenser, the water outlet of the condenser is connected to the water supply inlet of the primary heat exchanger, and the water supply outlet of the primary heat exchanger is connected to the water inlet of the deaerator.
[0007] Preferably, the steam condensate passes through the primary heat exchanger, the secondary heat exchanger, and the air preheater in sequence, becomes makeup water, and then enters the secondary heat exchanger, the condenser, the primary heat exchanger, and the deaerator in sequence.
[0008] Preferably, the temperature of the steam condensate is 80-100°C before entering the primary heat exchanger, the steam condensate temperature drops to 70-80°C after water-to-water heat exchange in the primary heat exchanger, the steam condensate temperature drops to 50-60°C after water-to-water heat exchange in the secondary heat exchanger, and then drops to 10-20°C after cold air heat exchange in the air preheater. The steam condensate at 10-20°C is used as part of the make-up water.
[0009] Preferably, the temperature of the boiler's feed water before entering the secondary heat exchanger is 20°C, the feed water temperature rises to 25-35°C after water-to-water heat exchange in the secondary heat exchanger, the feed water temperature rises to 50-60°C after flue gas heat exchange in the condenser, and the feed water temperature rises to 60-70°C after water-to-water heat exchange in the primary heat exchanger. The feed water at 60-70°C enters the deaerator.
[0010] The beneficial effects of the present invention are: (1) The water-to-water heat exchange in the primary heat exchanger increases the inlet water temperature of the deaerator and reduces the steam consumption of the deaerator.
[0011] (2) The water-to-water heat exchange in the secondary heat exchanger increases the water inlet temperature of the condenser, reduces the heat exchange temperature difference, and is beneficial to increasing the service life of the condenser.
[0012] (3) It can realize full-flow low-temperature water supply to the condenser under the condition of system condensate return, which is beneficial to reduce the exhaust temperature and improve the overall efficiency of the system.
[0013] (4) The air-water heat exchange in the air preheater increases the temperature of the combustion air, which is conducive to stabilizing and strengthening combustion.
[0014] (5) The condensation process of flue gas causes some harmful substances to dissolve in condensed water, reducing pollution emissions and benefiting the environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a structural schematic diagram of a method for deep utilization of steam condensate water according to the present invention.
[0016] Among them: primary heat exchanger 1; secondary heat exchanger 2; air preheater 3; condenser 4; deaerator 5; primary heat exchanger water inlet pipe 6; primary heat exchanger water outlet pipe 7; deaerator water inlet pipe 8; condenser water outlet pipe 9; condenser water inlet pipe 10; water supply pipe 11, secondary heat exchanger water outlet pipe 12; air preheater water outlet pipe 13. DETAILED DESCRIPTION
[0017] See also Figure 1The present invention relates to a deep utilization system of steam condensate, comprising a primary heat exchanger 1, a secondary heat exchanger 2, an air preheater 3, a condenser 4 and a deaerator 5. The primary heat exchanger 1 and the secondary heat exchanger 2 both adopt water-to-water heat exchange. The steam condensate enters the primary heat exchanger 1 through a primary heat exchanger water inlet pipe 6. The steam condensate outlet of the primary heat exchanger 1 is connected to the steam condensate inlet of the secondary heat exchanger 2 through a primary heat exchanger water outlet pipe 7. The steam condensate outlet of the secondary heat exchanger 2 is connected to the steam condensate inlet of the secondary heat exchanger 2 through a secondary heat exchanger water outlet pipe 8. The pipeline 12 is connected to the water inlet of the air preheater 3, the water outlet of the air preheater 3 is connected to the water supply pipeline 11 through the air preheater water outlet pipeline 13, the water supply pipeline 11 is connected to the water supply inlet of the secondary heat exchanger 2, the water supply outlet of the secondary heat exchanger 2 is connected to the water inlet of the condenser 4 through the condenser water inlet pipeline 10, the water outlet of the condenser 4 is connected to the water supply inlet of the primary heat exchanger 1 through the condenser water outlet pipeline 9, and the water supply outlet of the primary heat exchanger 1 is connected to the water inlet of the deaerator 5 through the deaerator water inlet pipeline 8.
[0018] Working principle: The 80-100°C steam condensate and the 50-60°C water generated by the heat exchange of the condenser 4 are exchanged with each other through the primary heat exchanger 1 to generate 70-80°C steam condensate and 60-70°C water. The 60-70°C water enters the deaerator 5, thereby increasing the water inlet temperature of the deaerator 5 and reducing the steam consumption of the deaerator 5. The 70-80℃ steam condensate and the 20℃ make-up water are exchanged with each other through the secondary heat exchanger 2 to produce 50-60℃ steam condensate and 25-35℃ water. The 25-35℃ water enters the condenser 4 to exchange heat with the flue gas to reduce the flue gas temperature. The 50-60℃ steam condensate enters the air preheater 3 to exchange heat with the cold air. Specifically, the water temperature of 25-35℃ water is increased after entering the condenser 4 for heat exchange, so that the heat exchange temperature difference is reduced, which is beneficial to improving the service life of the condenser 4; at the same time, the low-temperature water exchanges heat with the high-temperature flue gas, reducing the high-temperature flue gas of 130-160℃ to below 60℃, and the water vapor in the high-temperature flue gas is condensed when it is cooled, so that some harmful substances in the flue gas are dissolved in the condensed water, reducing pollution emissions, which is beneficial to environmental protection; the exhaust temperature is reduced, and the overall thermal efficiency is improved by about 4% or more; The 50-60°C steam condensate and -10-10°C air are exchanged with each other through the air preheater 3 to produce 10-20°C steam condensate and 5-20°C air. The increase in air temperature is beneficial to stabilizing and strengthening combustion, and the 10-20°C steam condensate can be used as make-up water and flow into the make-up water pipeline.
[0019] In addition to the above embodiments, the present invention also includes other implementation modes. Any technical solutions formed by equivalent transformation or equivalent replacement should fall within the protection scope of the claims of the present invention.
Claims
1. A method for deep utilization of steam condensate, characterized in that: The following steps are involved: The steam condensate enters the primary heat exchanger and exchanges heat with the water generated by the condenser. The water produced after the first-stage heat exchange enters the deaerator, and the steam condensate produced after the first-stage heat exchange enters the second-stage heat exchanger for water-to-water heat exchange; The water generated after the secondary heat exchange enters the condenser to exchange heat with the flue gas, and the steam condensate generated after the secondary heat exchange enters the air preheater to exchange heat with the cold air.
2. The method for deep utilization of steam condensate according to claim 1, characterized in that: The water produced after the secondary heat exchange enters the condenser and the water temperature rises after heat exchange, preparing for the water-to-water heat exchange in the primary heat exchanger. At the same time, the low-temperature water exchanges heat with the high-temperature flue gas to reduce the high-temperature flue gas to below 60°C. The water vapor in the high-temperature flue gas is condensed when it is cooled, and some harmful substances in the flue gas dissolve into the condensed water.
3. The method for deep utilization of steam condensate according to claim 1, characterized in that: The steam condensate outlet of the primary heat exchanger is connected to the steam condensate inlet of the secondary heat exchanger, the steam condensate outlet of the secondary heat exchanger is connected to the water inlet of the air preheater, the water outlet of the air preheater is connected to the water supply pipe, the water supply pipe is connected to the water supply inlet of the secondary heat exchanger, the water supply outlet of the secondary heat exchanger is connected to the water inlet of the condenser, the water outlet of the condenser is connected to the water supply inlet of the primary heat exchanger, and the water supply outlet of the primary heat exchanger is connected to the water inlet of the deaerator.
4. A method for deep utilization of steam condensate according to claim 1 or 3, characterized in that: The steam condensate passes through the primary heat exchanger, the secondary heat exchanger, and the air preheater in sequence, becomes makeup water, and then enters the secondary heat exchanger, the condenser, the primary heat exchanger, and the deaerator in sequence.
5. The method for deep utilization of steam condensate according to claim 1, characterized in that: The temperature of steam condensate is 80-100℃ before it enters the primary heat exchanger. After water-to-water heat exchange in the primary heat exchanger, the temperature of steam condensate drops to 70-80℃. After water-to-water heat exchange in the secondary heat exchanger, the temperature of steam condensate drops to 50-60℃. After cold air heat exchange in the air preheater, the temperature of steam condensate drops to 10-20℃. The steam condensate at 10-20℃ is used as part of the make-up water.
6. The method for deep utilization of steam condensate according to claim 1, characterized in that: The temperature of the boiler's feed water before entering the secondary heat exchanger is 20°C. After water-to-water heat exchange in the secondary heat exchanger, the feed water temperature rises to 25-35°C. After heat exchange with flue gas in the condenser, the feed water temperature rises to 50-60°C. After water-to-water heat exchange in the primary heat exchanger, the feed water temperature rises to 60-70°C. The feed water at 60-70°C enters the deaerator.