Membrane deoxygenization steam-water system

Abstract

The utility model discloses a membrane deoxidization steam-water system, which applies the advantage of membrane deoxidization, recycles low-quality waste heat to replace high-quality steam, and reasonably integrates waste heat resources. The system comprises a chemical water station; a desalted water tank; a membrane deoxidization skid-mounted module; a deoxidizing water tank; a high-pressure heater; a low-quality steam module; and a boiler; water output from the chemical water station sequentially passes through the desalting water tank and the membrane deoxidizing skid-mounted module and then is connected to an input port of the deoxidizing water tank, an output port of the deoxidizing water tank is connected to a first medium inlet of the high-pressure heater, and a first medium outlet of the high-pressure heater converges to a water inlet of the boiler. Deoxidized water is heated and evaporated through a boiler and then fed into a steam pocket for steam-water separation, saturated steam is reheated through the boiler, and then high-quality superheated steam is output; low-quality steam of the low-quality steam module is connected to a second medium inlet of the high-pressure heater, and a second medium outlet of the high-pressure heater is connected into the desalted water tank through an output water path.

Description

Technical Field

[0001] This utility model relates to the technical field of boiler feedwater treatment, specifically a membrane deoxygenation steam-water system. Background Technology

[0002] In the boiler feedwater treatment process, deoxygenation is a crucial step. Oxygen is the main corrosive substance in the boiler feedwater system, and it must be removed quickly. Otherwise, it will corrode the boiler feedwater system and components. Corrosive iron oxide will enter the boiler and deposit or adhere to the boiler tube walls and heating surfaces, forming insoluble iron scale that has poor heat transfer. Corroded iron scale will cause pitting on the inner wall of the pipes, increasing the resistance coefficient. In severe cases of pipe corrosion, pipe explosions may even occur.

[0003] Existing thermal deaerators fluctuate according to boiler load fluctuations, resulting in unstable deaeration effects and even failure to meet deaeration standards. Furthermore, existing thermal deaerators require the introduction of steam for deaeration and the discharge of some exhaust steam to remove oxygen. In addition, to prevent cavitation at the feedwater pump inlet, the thermal deaerator must be placed at a high position. Utility Model Content

[0004] To address the aforementioned problems, this utility model provides a membrane deoxygenation steam-water system, which leverages the advantages of membrane deoxygenation to recover and utilize low-quality waste heat to replace high-quality steam, thus rationally integrating waste heat resources.

[0005] A membrane deoxygenated water system, characterized in that it comprises:

[0006] Water treatment station;

[0007] Desalination tank;

[0008] Membrane deoxygenation skid-mounted module;

[0009] Deoxygenated water tank;

[0010] High-pressure heater;

[0011] Low-grade steam module;

[0012] And boilers;

[0013] The water output from the water treatment station passes sequentially through the demineralized water tank and the membrane deoxygenation skid module before entering the inlet of the deoxygenated water tank. The outlet of the deoxygenated water tank is connected to the first medium inlet of the high-pressure heater. The first medium outlet of the high-pressure heater flows into the water inlet of the boiler. After the deoxygenated water is heated and evaporated by the boiler, it is sent to the steam drum for steam-water separation. The saturated steam is reheated by the boiler again and output as high-quality superheated steam.

[0014] The low-quality steam from the low-quality steam module is connected to the second medium inlet of the high-pressure heater, and the second medium outlet of the high-pressure heater is connected to the demineralized water tank through the output water path.

[0015] Its further features are:

[0016] The deoxygenated water tank is equipped with a nitrogen sealing module, and an external nitrogen pipeline supplies nitrogen to the nitrogen sealing module to ensure that the water in the deoxygenated water tank does not reabsorb oxygen.

[0017] The demineralized water tank pumps water into the main water inlet of the membrane deoxygenation skid module via a demineralized water pump to ensure a stable and reliable water flow.

[0018] The outlet of the deoxygenated water tank is connected to the first medium inlet of the high-pressure heater via a water pump to ensure a stable and reliable water flow.

[0019] The membrane deoxygenation skid-mounted module includes at least one set of deoxygenation membrane contactors. Each set of deoxygenation membrane contactors includes a contactor body, an oxygen-containing water inlet, a deoxygenated water outlet, a nitrogen inlet, and a waste gas outlet. The water inlets and outlets of several sets of deoxygenation membrane contactors are connected in series sequentially, and the nitrogen inlets and waste gas outlets are all connected in parallel. The oxygen-containing water inlet of the first-stage deoxygenation membrane contactor formed in series is the total water inlet, and the deoxygenated water outlet of the last-stage deoxygenation membrane contactor formed in series is the total water outlet. Each set of nitrogen inlets of the membrane deoxygenation skid-mounted module is connected in parallel to a nitrogen purging pipeline, and each set of waste gas outlets of the membrane deoxygenation skid-mounted module discharges a mixture of oxygen and nitrogen gas through a waste gas discharge pipeline.

[0020] The exhaust gas discharge pipeline is sequentially equipped with a first pressure gauge, an air vent valve, and a water ring vacuum pump; the nitrogen purging pipeline is sequentially equipped with a switch valve, a gas flow meter, a second pressure gauge, and a needle valve along the gas inlet direction.

[0021] The nitrogen pipeline simultaneously supplies nitrogen to the nitrogen purging pipeline and the nitrogen sealing module.

[0022] Traditional thermal deaerators fluctuate with boiler load, resulting in unstable deaeration. To prevent cavitation at the feedwater pump inlet, the thermal deaerator must be placed at a high position. With this system, the membrane deaerator skid module can be placed at a low position, making efficient use of space. It leverages the advantages of membrane deaeration, recovering and utilizing low-grade steam instead of high-grade steam, and rationally integrating waste heat resources, reducing exhaust steam losses. Furthermore, it has a small footprint, is easy to operate, and produces no wastewater, waste gas, or waste residue. The boiler feedwater temperature can be flexibly adjusted according to the boiler load, ensuring system stability and reliability. While safely completing production, it achieves heat recovery and utilization, saving electricity and generating economic benefits for heating. Attached Figure Description

[0023] Figure 1 This is a schematic block diagram of the system connection corresponding to this utility model;

[0024] Figure 2 This is a schematic diagram of the structure of the membrane deoxygenation skid-mounted module used in this utility model;

[0025] Figure 3 This is a schematic diagram of the deoxidation membrane contactor of this utility model;

[0026] The names corresponding to the serial numbers in the diagram are as follows:

[0027] Water treatment station 10, demineralized water tank 20, demineralized water pump 21, membrane deoxygenation skid module 30, deoxygenated water tank 40, feed water pump 41, nitrogen sealing module 42, high pressure heater 50, output water circuit 51, low-grade steam module 60, boiler 70, steam drum 80, deoxygenation membrane contactor 90, first-stage deoxygenation membrane contactor 91, second-stage deoxygenation membrane contactor 92;

[0028] Contactor body 1, oxygenated water inlet 2, deoxygenated water outlet 3, nitrogen inlet 4, exhaust gas outlet 5, nitrogen purging pipeline 6, switch valve 61, gas flow meter 62, second pressure gauge 63, needle valve 64, exhaust gas discharge pipeline 7, first pressure gauge 71, vent valve 72, water ring vacuum pump 73. Detailed Implementation

[0029] A membrane deoxygenation steam-water system, characterized in that it includes a water treatment station 10, a demineralized water tank 20, a membrane deoxygenation skid-mounted module 30, a deoxygenated water tank 40, a high-pressure heater 50, a low-grade steam module 60, and a boiler 70.

[0030] Water output from the water treatment station 10 passes through the demineralized water tank 20 and is then connected to the main water inlet of the membrane deoxygenation skid module 30 via the demineralized water pump 21. The main water outlet of the membrane deoxygenation skid module 30 is connected to the inlet of the deoxygenated water tank 40. The outlet of the deoxygenated water tank 40 is connected to the first medium inlet of the high-pressure heater 50 via the feed water pump 41. The first medium outlet of the high-pressure heater 50 flows to the inlet of the boiler 70. After being heated and evaporated by the boiler 70, the deoxygenated water is sent to the steam drum 80 for steam-water separation. The saturated steam is reheated by the boiler 70 and output as high-quality superheated steam. The low-quality steam from the low-grade steam module 60 is connected to the second medium inlet of the high-pressure heater 50. The second medium outlet of the high-pressure heater 50 is connected to the demineralized water tank 20 via the output water circuit 51.

[0031] In a specific embodiment, a nitrogen sealing module 42 is provided around the deoxygenated water tank 40. An external nitrogen pipeline (not shown in the figure, but can be set according to the position) supplies nitrogen to the nitrogen sealing module 42 to ensure that the water in the deoxygenated water tank 40 will not reabsorb oxygen.

[0032] In specific implementation, the membrane deoxygenation skid-mounted module 30 includes two sets of deoxygenation membrane contactors 90. Each set of deoxygenation membrane contactors 90 includes a contactor body 1, an oxygenated water inlet 2, a deoxygenated water outlet 3, a nitrogen inlet 4, and a waste gas outlet 5. The water inlets and outlets of the two sets of deoxygenation membrane contactors 90 are connected in series sequentially, and the nitrogen inlets 4 and waste gas outlets 5 are set in parallel. The oxygenated water inlet 2 of the first-stage deoxygenation membrane contactor 91 formed in series is the total water inlet, and the deoxygenated water outlet 2 of the second-stage deoxygenation membrane contactor 92 formed in series is the total water outlet. Each set of nitrogen inlets 4 of the membrane deoxygenation skid-mounted module 30 is connected in parallel to the nitrogen purging pipeline 6, and each set of waste gas outlets 5 of the membrane deoxygenation skid-mounted module 30 discharges a mixture of oxygen and nitrogen gas through the waste gas discharge pipeline 7.

[0033] The exhaust gas discharge pipeline 7 is sequentially equipped with a first pressure gauge 71, an air vent valve 72, and a water ring vacuum pump 73. The nitrogen purging pipeline 6 is sequentially equipped with a switch valve 61, a gas flow meter 62, a second pressure gauge 63, and a needle valve 64 along the gas inlet direction.

[0034] The nitrogen pipeline simultaneously supplies nitrogen to the nitrogen purging pipeline 6 and the nitrogen sealing module 42.

[0035] The demineralized water, after pretreatment at the water treatment station 10, is stored in the demineralized water tank 20 for later use. It is then pumped by the demineralized water pump 21 into the membrane deoxygenation skid module 30 for deoxygenation treatment. The deoxygenated water is called deoxygenated water and is stored in the deoxygenated water tank 40. The deoxygenated water tank 40 is nitrogen-sealed by the nitrogen sealing module 42. The feed water pump 41 sends the deoxygenated water to the high-pressure heater 50. After being heated to an appropriate temperature by low-grade steam, it is sent to the boiler 70. After being heated and evaporated by the boiler 70, it is sent to the steam drum 80 for steam-water separation. The saturated steam is reheated by the boiler 70 to produce high-quality superheated steam.

[0036] Traditional thermal deaerators fluctuate with boiler load, resulting in unstable deaeration. To prevent cavitation at the feedwater pump inlet, the thermal deaerator must be placed at a high position. This system, however, features a skid-mounted membrane deaerator module that can be placed at a low position, making efficient use of space. It leverages the advantages of membrane deaeration, recovering and reusing low-grade steam to replace high-grade steam, and rationally integrating waste heat resources, thus reducing exhaust steam losses. Furthermore, it has a small footprint, is easy to operate, and produces no wastewater, waste gas, or waste residue. The boiler feedwater temperature can be flexibly adjusted according to the boiler load, ensuring system stability and reliability. While safely completing production, it achieves heat recovery and utilization, saving electricity and generating economic benefits for heating.

[0037] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0038] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A membrane deoxygenated steam-water system, characterized in that, It includes: Water treatment station; Desalination tank; Membrane deoxygenation skid-mounted module; Deoxygenated water tank; High-pressure heater; Low-grade steam module; And boilers; The water output from the water treatment station passes sequentially through the demineralized water tank and the membrane deoxygenation skid module before entering the inlet of the deoxygenated water tank. The outlet of the deoxygenated water tank is connected to the first medium inlet of the high-pressure heater. The first medium outlet of the high-pressure heater flows into the water inlet of the boiler. After the deoxygenated water is heated and evaporated by the boiler, it is sent to the steam drum for steam-water separation. The saturated steam is reheated by the boiler again and output as high-quality superheated steam. The low-quality steam from the low-quality steam module is connected to the second medium inlet of the high-pressure heater, and the second medium outlet of the high-pressure heater is connected to the demineralized water tank through the output water path.

2. The membrane deoxygenation steam-water system according to claim 1, characterized in that: A nitrogen sealing module is installed around the deoxygenated water tank, and an external nitrogen pipeline supplies nitrogen to the nitrogen sealing module.

3. The membrane deoxygenation steam-water system according to claim 1, characterized in that: The demineralized water tank pumps water into the main water inlet of the membrane deoxygenation skid module via a demineralized water pump.

4. The membrane deoxygenation steam-water system according to claim 1, characterized in that: The outlet of the deoxygenated water tank is connected to the first medium input port of the high-pressure heater via a water pump.

5. A membrane deoxygenation steam-water system according to claim 2, characterized in that: The membrane deoxygenation skid-mounted module includes at least one set of deoxygenation membrane contactors. Each set of deoxygenation membrane contactors includes a contactor body, an oxygen-containing water inlet, a deoxygenated water outlet, a nitrogen inlet, and a waste gas outlet. The water inlets and outlets of several sets of deoxygenation membrane contactors are connected in series sequentially, and the nitrogen inlets and waste gas outlets are all connected in parallel. The oxygen-containing water inlet of the first-stage deoxygenation membrane contactor formed in series is the total water inlet, and the deoxygenated water outlet of the last-stage deoxygenation membrane contactor formed in series is the total water outlet. Each set of nitrogen inlets of the membrane deoxygenation skid-mounted module is connected in parallel to a nitrogen purging pipeline, and each set of waste gas outlets of the membrane deoxygenation skid-mounted module discharges a mixture of oxygen and nitrogen gas through a waste gas discharge pipeline.

6. The membrane deoxygenation steam-water system according to claim 5, characterized in that: The exhaust gas discharge pipeline is sequentially equipped with a first pressure gauge, a vent valve, and a water ring vacuum pump, while the nitrogen purging pipeline is sequentially equipped with a switch valve, a gas flow meter, a second pressure gauge, and a needle valve along the gas inlet direction.

7. A membrane deoxygenation steam-water system according to claim 5, characterized in that: The nitrogen pipeline simultaneously supplies nitrogen to the nitrogen purging pipeline and the nitrogen sealing module.

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