Deep utilization system for steam condensation water

Abstract

The utility model relates to a deep utilization system of steam condensation water, which comprises a primary heat exchanger, a secondary heat exchanger, an air preheater, a condenser and a deaerator, and a steam condensation water outlet of the primary heat exchanger is connected with a steam condensation water inlet of the secondary heat exchanger. A steam condensation water outlet of the second-stage heat exchanger is connected with a water inlet of an air preheater, a water outlet of the air preheater is connected into a water supplementing pipeline, the water supplementing pipeline is connected with a water supplementing inlet of the second-stage heat exchanger, and a water supplementing outlet of the second-stage heat exchanger is connected with a water inlet of a condenser. A water outlet of the condenser is connected with a water supplementing inlet of the first-stage heat exchanger, and a water supplementing outlet of the first-stage heat exchanger is connected with a water inlet of the deaerator. Steam condensation water can be fully utilized for heat exchange, the water inlet temperature of a boiler system is increased, and boiler energy consumption is reduced; the combustion-supporting air temperature is increased, and combustion is stabilized and enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of steam condensate recovery and utilization, in particular to a steam condensate deep utilization system. Background Art

[0002] Steam condensate is water that contains energy. During the steam heating process, only the latent heat of steam is effectively utilized, while the sensible heat of steam is almost unused, accounting for 20% to 30% of the total heat of steam. Furthermore, uncontaminated steam condensate is close to pure water in quality and can be used as high-quality boiler feed water or process water. Therefore, there is an urgent need to design a system for the deep utilization of steam condensate that can fully utilize the condensate for heat exchange, increase the inlet water temperature of the boiler system, reduce boiler energy consumption, and increase the combustion air temperature to stabilize and enhance combustion. Utility Model Content

[0003] The purpose of this utility model is to overcome the above-mentioned shortcomings and provide a deep utilization system 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 combustion air temperature, stabilize and enhance combustion.

[0004] The purpose of this utility model is achieved in this way:

[0005] A system for deep utilization of steam condensate, comprising a primary heat exchanger, a secondary heat exchanger, an air preheater, a condenser and a deaerator, wherein 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 a 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.

[0006] Preferably, the primary heat exchanger and the secondary heat exchanger both use water-to-water heat exchange.

[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 before entering the first-stage heat exchanger is 80-100°C, the steam condensate temperature drops to 70-80°C after water-to-water heat exchange in the first-stage heat exchanger, the steam condensate temperature drops to 50-60°C after water-to-water heat exchange in the second-stage 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 heat exchange with flue gas 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 utility model are:

[0011] (1) The water-to-water heat exchange in the first-stage heat exchanger increases the inlet water temperature of the deaerator and reduces the steam consumption of the deaerator.

[0012] (2) The water-to-water heat exchange in the secondary heat exchanger increases the water inlet temperature of the condenser and reduces the heat exchange temperature difference, which is beneficial to increasing the service life of the condenser.

[0013] (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.

[0014] (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.

[0015] (5) The condensation process of flue gas allows some harmful substances to dissolve in condensed water, reducing pollution emissions and benefiting environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural schematic diagram of a deep utilization system of steam condensate water in the utility model.

[0017] Among them: first-stage heat exchanger 1; second-stage heat exchanger 2; air preheater 3; condenser 4; deaerator 5; first-stage heat exchanger water inlet pipe 6; first-stage 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, second-stage heat exchanger water outlet pipe 12; air preheater water outlet pipe 13. DETAILED DESCRIPTION

[0018] See also Figure 1The utility model relates to a kind of deep utilization system of steam condensate, including primary heat exchanger 1, secondary heat exchanger 2, air preheater 3, condenser 4 and deaerator 5, the primary heat exchanger 1 and secondary heat exchanger 2 all adopt water-water heat exchange, steam condensate enters primary heat exchanger 1 by primary heat exchanger inlet pipeline 6, the steam condensate outlet of primary heat exchanger 1 is connected the steam condensate inlet of secondary heat exchanger 2 by primary heat exchanger outlet pipeline 7, the steam condensate outlet of secondary heat exchanger 2 is connected the water inlet of air preheater 3 by secondary heat exchanger outlet pipeline 12, the water outlet of air preheater 3 is connected make-up water pipeline 11 by air preheater outlet pipeline 13, make-up water pipeline 11 is connected the make-up water inlet of secondary heat exchanger 2, the make-up water outlet of secondary heat exchanger 2 is connected the water inlet of condenser 4 by condenser inlet pipeline 10, the water outlet of condenser 4 is connected the make-up water inlet of primary heat exchanger 1 by condenser outlet pipeline 9, the make-up water outlet of primary heat exchanger 1 is connected with the water inlet of deaerator 5 by deaerator inlet pipeline 8.

[0019] Working principle:

[0020] 80~100 ℃ steam condensate and 50~60 ℃ water generated by heat exchange of condenser 4 are water-water heat exchanged by primary heat exchanger 1, generate 70~80 ℃ steam condensate and 60~70 ℃ water, 60~70 ℃ water enters deaerator 5, improve the water temperature of deaerator 5, reduce the steam consumption of deaerator 5;

[0021] 70~80 ℃ steam condensate and 20 ℃ make-up water are water-water heat exchanged by secondary heat exchanger 2, generate 50~60 ℃ steam condensate and 25~35 ℃ water, 25~35 ℃ water enters condenser 4 and exchanges heat with flue gas, reduce the temperature of flue gas, 50~60 ℃ steam condensate enters air preheater 3 and exchanges heat with cold air;

[0022] Specifically: the water temperature is improved after 25~35 ℃ water exchanges heat in condenser 4, so that the heat exchange temperature difference is reduced, which is beneficial to improve the service life of condenser 4; at the same time, low-temperature water exchanges heat with high-temperature flue gas, reduces the high-temperature flue gas to below 60 ℃, and the water vapor in high-temperature flue gas condenses when it is cold, so that part of harmful substances in flue gas dissolve into condensate, reduce pollution emission, which is beneficial to environmental protection; reduce the flue gas temperature, and the overall thermal efficiency is improved by more than 4%;

[0023] 50~60 ℃ steam condensate and-10~10 ℃ air are gas-water heat exchanged by air preheater 3, generate 10~20 ℃ steam condensate and 5~20 ℃ air, the improvement of air temperature is beneficial to stabilize and strengthen combustion, and 10~20 ℃ steam condensate can be used as make-up water and merged into make-up water pipeline.

[0024] In addition to the above embodiments, the present invention also includes other implementation methods. Any technical solutions formed by equivalent transformation or equivalent replacement should fall within the scope of protection of the claims of the present invention.

Claims

1. A system for deep utilization of steam condensate, characterized by: It includes a primary heat exchanger, a secondary heat exchanger, an air preheater, a condenser and a deaerator. 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.

2. The deep utilization system of steam condensate according to claim 1, characterized in that: The primary heat exchanger and the secondary heat exchanger both adopt water-to-water heat exchange.

3. The deep utilization system of steam condensate according to claim 2, characterized in that: The steam condensate passes through the primary heat exchanger, the secondary heat exchanger, and the air preheater in sequence, becomes make-up water, and then enters the secondary heat exchanger, the condenser, the primary heat exchanger, and the deaerator in sequence.

4. The deep utilization system of steam condensate according to claim 1, characterized in that: The temperature of the steam condensate before entering the first-stage heat exchanger is 80-100℃. After the water-to-water heat exchange in the first-stage heat exchanger, the temperature of the steam condensate drops to 70-80℃. After the water-to-water heat exchange in the second-stage heat exchanger, the temperature of the steam condensate drops to 50-60℃. After the cold air heat exchange in the air preheater, the temperature of the steam condensate drops to 10-20℃. The steam condensate at 10-20℃ is used as part of the make-up water.

5. The deep utilization system of steam condensate according to claim 4, characterized in that: The temperature of the boiler's feed water is 20°C before it enters the secondary heat exchanger. 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.

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