A marine low-energy consumption boiler water deoxidizing device

Abstract

The application relates to a marine low-energy-consumption boiler water deoxidizing device, which comprises a bottom plate for mounting the deoxidizing device on a deck, a support fixedly arranged on the bottom plate, at least one membrane shell contactor fixedly arranged on the support, the membrane shell contactor being in a hollow cylindrical structure, an internal cavity being formed in the membrane shell contactor, a water inlet and a water outlet being arranged on the membrane shell contactor, and the water inlet and the water outlet being communicated with the cavity. Through the above structure, a baffle is arranged in the cavity of the membrane shell contactor, the cavity is divided into a water inlet side chamber and a water outlet side chamber, and a through hole is arranged on the baffle, so that a single water flow in the water inlet side chamber is divided into multiple branch flows and then enters the water outlet side chamber, thereby guiding the water flow to flow close to the hollow fibers of the cavity wall, increasing the contact uniformity and contact area of the water body and the hollow fibers, avoiding the water flow short circuit or deflection phenomenon, and effectively improving the deoxidizing efficiency.

Description

Technical Field

[0001] This invention relates to a deoxygenation device, particularly a low-energy-consumption marine boiler water deoxygenation device. It uses a baffle to divide the cavity of a membrane contactor into an inlet chamber and an outlet chamber. Through holes are opened on the baffle, causing the single stream of water in the inlet chamber to be divided into multiple streams before entering the outlet chamber. This guides the water flow to adhere closely to the hollow fibers on the cavity wall, increasing the uniformity and contact area between the water and the hollow fibers, preventing short-circuiting or flow deviation, and effectively improving deoxygenation efficiency. Background Technology

[0002] In offshore oil and gas platform boiler feedwater systems, the presence of corrosive gases such as dissolved oxygen accelerates the oxidation and pitting of metal pipelines, threatening equipment safety and shortening its service life. Traditional thermal deoxygenation technology relies on high-temperature steam to heat water to boiling to release dissolved gases, but it is energy-intensive, requires bulky equipment, and needs to be installed at high positions, making it difficult to adapt to the harsh environment of offshore platforms where space is limited and energy costs are sensitive. While chemical deoxygenation methods, such as adding sodium sulfite, can achieve deoxygenation at room temperature, they pose risks of reagent residue, increased operating costs, and secondary pollution. Membrane deoxygenation technology has the potential for low energy consumption, but conventional membrane modules are prone to membrane fiber breakage, hydrophobic failure, or uneven flow channel distribution due to water flow impact, resulting in a sharp drop in deoxygenation efficiency and increased operation and maintenance costs.

[0003] To address the aforementioned issues, existing technologies have attempted to use hollow fiber membranes for deoxygenation. The basic working principle involves utilizing the microporous structure of hydrophobic membrane fibers to create a pressure difference across the fibers, causing dissolved oxygen in the water to penetrate the micropores and be extracted from the internal cavity of the membrane fibers under the pressure difference. However, existing membrane deoxygenation devices still have the following shortcomings when practically applied to offshore platforms: the water flow distribution within the membrane module is relatively uniform; water is prone to flow deviation or short-circuiting when flowing through the membrane fiber bundle, with some water flowing out directly without sufficient contact with the membrane fibers, resulting in low overall deoxygenation efficiency; simultaneously, the low-frequency vibrations and turbulence caused by ship navigation at sea can easily cause the membrane fibers to repeatedly oscillate in the water flow, leading to membrane fiber breakage and severely affecting the long-term operational stability and service life of the device. Summary of the Invention

[0004] To address the aforementioned deficiencies in existing technologies, this invention provides a low-energy-consumption marine boiler water deaerator. It divides the cavity of the membrane contactor into an inlet chamber and an outlet chamber by installing a baffle plate within the cavity. Through holes are formed on the baffle plate, causing the single stream of water in the inlet chamber to be split into multiple streams before entering the outlet chamber. This guides the water flow closely along the hollow fibers on the cavity wall, increasing the uniformity and contact area between the water and the hollow fibers, preventing short-circuiting or flow deviation, and effectively improving deaeration efficiency.

[0005] To achieve the above objectives, the present invention provides a low-energy-consumption marine boiler water deaerator, comprising: A bottom plate for mounting the deaerator on the deck; The bracket is fixedly mounted on the base plate; At least one membrane housing contactor is fixedly mounted on the bracket. The membrane housing contactor has a hollow cylindrical structure with a cavity inside. The membrane housing contactor is provided with an inlet and an outlet, and both the inlet and the outlet are connected to the cavity. Hollow fibers are disposed within the cavity. The hollow fibers are made of hydrophobic fiber membrane filaments, and airflow channels are formed inside the hollow fibers. A baffle is fixedly installed in the cavity, dividing the cavity into an inlet side chamber and an outlet side chamber along the water flow direction. The baffle is provided with several through holes to divide the water flow in the inlet side chamber into multiple branches before flowing into the outlet side chamber. The diaphragm contactor is also provided with an air extraction port and an air inlet, both of which are connected to the airflow channel.

[0006] Traditional thermal deoxygenation technology is energy-intensive, requires bulky equipment, and necessitates high-level installation, making it unsuitable for the harsh environments of offshore platforms where space is limited and energy costs are critical. Chemical deoxygenation methods, on the other hand, suffer from reagent residues, rising operating costs, and the risk of secondary pollution. To address these issues, this invention employs a baffle to divide the cavity of the membrane contactor into an inlet chamber and an outlet chamber. Through holes are created in the baffle, causing the single stream of water in the inlet chamber to be divided into multiple streams before entering the outlet chamber. This guides the water flow closely along the hollow fibers on the cavity wall, increasing the uniformity and contact area between the water and the hollow fibers, preventing short-circuiting or flow deviation, and effectively improving deoxygenation efficiency.

[0007] The hollow fiber is woven from hydrophobic fiber membrane filaments into a fabric, which is then wound into a columnar structure and placed inside the cavity.

[0008] The columnar structure of the hollow fiber is disposed on the peripheral wall of the cavity.

[0009] The water inlet chamber is a water pipe located on the side of the baffle closer to the water inlet, and the water outlet chamber is a water collection pipe located on the side of the baffle closer to the water outlet.

[0010] The membrane housing contactor is a plurality of such contactors, and the plurality of such contactors are arranged vertically on the support.

[0011] It also includes an inlet pipe and an outlet pipe, with all the inlets connected to the inlet pipe and all the outlets connected to the outlet pipe.

[0012] The air extraction port is located at one end of the diaphragm contactor, and the air inlet is located at the other end of the diaphragm contactor.

[0013] The baffle has several through holes located at its four edges.

[0014] The base plate is also equipped with a ladder, which is fixedly connected to the support.

[0015] The air extraction port is used to connect to a vacuum pump, and the air inlet is open to the atmosphere.

[0016] Through the above structural design, this invention incorporates a baffle within the cavity of the membrane contactor, dividing the cavity into an inlet chamber and an outlet chamber. Through holes are formed on the baffle, allowing the single stream of water in the inlet chamber to be split into multiple streams before entering the outlet chamber. This guides the water flow closely along the hollow fibers on the cavity wall, increasing the uniformity and contact area between the water and the hollow fibers, preventing short-circuiting or flow deviation, and effectively improving deoxygenation efficiency. Simultaneously, by configuring the hollow fibers as a structure woven from hydrophobic membrane filaments into a fabric and wound into a column, each filament is constrained and fixed by adjacent filaments, preventing relative swaying under water flow impact. This avoids filament breakage caused by water flow impact and ship turbulence, ensuring stable deoxygenation efficiency under different sea conditions and extending the device's service life. Attached Figure Description

[0017] Figure 1 This is a three-dimensional schematic diagram of a marine low-energy boiler water deaeration device according to the present invention; Figure 2 This is a schematic diagram of the water flow and airflow direction of a marine low-energy boiler water deaerator according to the present invention; Figure 3 This is a side view of the membrane housing contactor of a marine low-energy boiler water deaeration device according to the present invention. Detailed Implementation

[0018] The directions or similar terms used throughout this invention, such as "front," "back," "left," "right," "top," "bottom," "inner," "outer," and "side," are mainly for reference to the directions in the accompanying drawings. These directions or similar terms are only used to assist in explaining and understanding the various embodiments of this invention and are not intended to limit this invention.

[0019] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. However, the embodiments described are only used to illustrate the technical features of the present invention and are not intended to limit the scope of protection of the present invention.

[0020] Please see Figures 1 to 3As shown, the present invention discloses a low-energy-consumption marine boiler water deaerator, mainly comprising a base plate 1, a support 2, at least one membrane contactor 5, hollow fiber optic cable 8, and a baffle 7. The base plate 1 serves as the mounting foundation for the entire device, used to fix the deaerator on the deck of an offshore platform. The base plate 1 is made of corrosion-resistant alloy material to withstand the corrosive environment of high salt spray at sea. The support 2 is fixedly mounted above the base plate 1. The support 2 has a frame structure and is used to support and fix the membrane contactor 5 and other auxiliary components, keeping the membrane contactor 5 in a predetermined position. In this embodiment, a ladder 3 is also provided on the base plate 1, which is fixedly connected to the support 2. The ladder 3 allows access to the support 2, facilitating routine maintenance and repair of the membrane contactor 5 and connecting pipes by operators.

[0021] like Figure 1 As shown, the membrane contactor 5 is fixedly mounted on the bracket 2. In this embodiment, there are multiple membrane contactors 5, all of which are vertically distributed on the bracket 2. The membrane contactor 5 is a hollow cylindrical structure, with an internal cavity for accommodating water flow and performing gas-liquid separation. The membrane contactor 5 is made of a high-pressure resistant material to withstand water pressure and vacuum pressure during operation. A water inlet 11 is fixedly provided at the bottom of the membrane contactor 5, and a water outlet 12 is fixedly provided at the top of the membrane contactor 5. Both the water inlet 11 and the water outlet 12 are connected to the cavity of the membrane contactor 5. The boiler feedwater to be treated enters the cavity through the water inlet 11, and flows out through the water outlet 12 after deoxygenation treatment. All the inlets 11 of the membrane contactors 5 are connected to the same inlet pipe 4, and all the outlets 12 of the membrane contactors 5 are connected to the same outlet pipe 6, thereby realizing the parallel operation of multiple membrane contactors 5. The inlet pipe 4 is used to distribute the boiler feedwater to be treated to each membrane contactor 5, and the outlet pipe 6 collects the water that has been deoxygenated in each membrane contactor 5 and introduces it into the boiler.

[0022] Please see Figure 2As shown, hollow fibers 8 and baffles 7 are disposed inside the cavity of the membrane contactor 5. The hollow fibers 8 are disposed inside the cavity and closely adhere to the inner wall of the membrane contactor 5. The two ends of the columnar structure of the hollow fibers 8 are fixed to the cavity of the membrane contactor 5 by epoxy resin potting layers. Specifically, at both ends of the cavity of the membrane contactor 5, epoxy resin potting material fills the annular gap between the columnar structure of the hollow fibers 8 and the inner wall of the membrane contactor 5, and penetrates into the gaps between the membrane fibers at the ends of the columnar structure of the hollow fibers 8. After curing, it forms a dense tube sheet structure, through which the exhaust port 13 and the inlet port 14 pass into the cavity of the membrane contactor 5. The tube sheet structure firmly bonds and fixes the ends of each hollow fiber 8, so that the columnar structure of the hollow fiber 8 is axially positioned in the cavity; on the other hand, the outer periphery of the tube sheet is tightly fitted with the inner wall of the membrane contactor 5 to form a sealed fit, which isolates the water flow area from the air extraction port 13 and air inlet port 14 area at the end of the membrane contactor 5.

[0023] The hollow fiber 8 is made of hydrophobic fiber membrane filaments, which are made of hydrophobic polymer materials such as polypropylene (PP) or polyvinylidene fluoride (PVDF). Its surface has a microporous structure, with pore sizes much smaller than the diameter of a water droplet but larger than the diameter of a gas molecule. Therefore, liquid water cannot penetrate the membrane wall, while gas molecules such as oxygen dissolved in the water can penetrate the micropores under pressure difference. The interior of the hollow fiber 8 forms hollow airflow channels, allowing gas penetrating the membrane wall to flow along the inside of the membrane filaments and be extracted. Specifically, the hydrophobic fiber membrane filaments are first woven into a fabric, then wound into a cylindrical structure. The wound hollow fiber 8 cylindrical structure is inserted into the cavity of the membrane shell contactor 5 and attached to the peripheral wall of the cavity. By weaving the membrane filaments into a fabric and then winding it into a column, each filament is constrained and fixed by adjacent filaments through the weaving structure. This prevents relative swaying under water flow impact, effectively eliminating filament breakage caused by water flow impact and ship turbulence. Simultaneously, the columnar structure increases the packing density and effective contact area of ​​the hollow fibers 8 per unit volume, improving deoxygenation efficiency. Furthermore, the tightness of the winding and interlayer friction give the entire columnar structure excellent structural stability, effectively offsetting the impact of low-frequency vibrations caused by ship navigation on the hollow fibers 8, ensuring stable deoxygenation efficiency under different sea conditions.

[0024] The baffle 7 is fixedly installed inside the cavity of the membrane housing contactor 5, and the outer diameter of the baffle 7 is adapted to the inner diameter of the hollow fiber 8 columnar structure. Specifically, the hollow fiber 8 columnar structure is a hollow cylindrical body made of wound silk cloth, with an axially extending internal space in its center. The outer edge of the baffle 7 is fixedly connected to the membrane housing contactor 5 through several connecting blocks, so that the baffle 7 is located inside the cavity of the hollow fiber 8.

[0025] The baffle 7 has its surface perpendicular to the axial direction of the membrane contactor 5, dividing the cavity into two independent chambers along the water flow direction. The chamber near the inlet 11 is the inlet-side chamber, and the chamber near the outlet 12 is the outlet-side chamber. In this embodiment, the inlet-side chamber is specifically the water pipe 9 located on the side of the baffle 7 near the inlet 11, and the outlet-side chamber is specifically the water collection pipe 10 located on the side of the baffle 7 near the outlet 12. Multiple through holes are provided around the perimeter of the baffle 7, and these through holes are evenly distributed along the circumference of the baffle 7. When the water flow in the main water pipe 9 passes through the baffle 7, it is divided into multiple branches by the various through holes around the baffle 7. This allows the water flow in the main water pipe 9 to flow into the water collection pipe 10 while adhering closely to the hollow fiber 8 on the cavity periphery wall. This ensures that the water flow makes full contact with the hollow fiber 8 as it flows through the membrane contactor 5, preventing the water flow from directly short-circuiting into the water collection pipe 10 from the center of the cavity without contacting the hollow fiber 8, which would reduce the dissolved oxygen removal efficiency in the water. At the same time, since the hollow fiber 8 is located on the periphery wall of the cavity, and the baffle 7 is located inside the columnar structure of the hollow fiber 8, the water flowing out of the through holes of the baffle 7 will inevitably flow along the cavity periphery wall, thus forming a uniform and sufficient contact between the water flow and the hollow fiber 8.

[0026] The membrane contactor 5 is also equipped with an air extraction port 13 and an air inlet 14. The air extraction port 13 is located at one end of the membrane contactor 5, and the air inlet 14 is located at the other end. Both the air extraction port 13 and the air inlet 14 are connected to the airflow channel inside the hollow fiber 8. The air extraction port 13 is used to connect to a vacuum pump, and the air inlet 14 is connected to the atmosphere. When the vacuum pump is started, it continuously evacuates the airflow channel of the hollow fiber 8 through the air extraction port 13, reducing the pressure inside the airflow channel to a level far lower than the pressure on the water flow side, thereby creating a stable pressure difference on both sides of the membrane wall of the hollow fiber 8. Under the action of this pressure difference, dissolved oxygen in the water in the water pipe 9 continuously passes through the micropores on the wall of the hollow fiber 8 and enters the airflow channel inside the hollow fiber 8. It is then extracted from the system through the air extraction port 13 along with the airflow generated by the vacuum pump, thus achieving room temperature removal of dissolved oxygen from the water. The air inlet 14 is connected to the atmosphere, ensuring a constant supply of air in the airflow channel, which is beneficial for gas flow and oxygen carry-out. After deoxygenation treatment, the water flows into the water collection pipe 10 through the through hole of the baffle 7. The water collection pipe 10 is connected to the boiler through the water outlet pipe 6, thereby continuously injecting qualified feedwater after deoxygenation into the boiler.

[0027] As can be seen from the above structure, the working process of the marine low-energy boiler water deoxygenation device provided by the present invention is as follows: The boiler feedwater to be treated is distributed to the inlet 11 of each membrane contactor 5 through the inlet pipe 4 and enters the main water pipe 9; the water flows upward in the main water pipe 9, and after encountering the baffle 7, it is divided into multiple branches by the through holes around the baffle 7. The hollow fiber 8 close to the cavity periphery flows into the water collection pipe 10; during this process, the vacuum pump continuously evacuates the airflow channel of the hollow fiber 8 through the air extraction port 13. The oxygen dissolved in the water penetrates the micropores of the hollow fiber 8 and enters the airflow channel under the pressure difference, and is discharged from the air extraction port 13 with the suction airflow; the deoxygenated water is collected in the water collection pipe 10 and sent to the boiler from the water outlet 12 through the water outlet pipe 6 to complete the entire deoxygenation process.

Claims

1. A low-energy-consumption marine boiler water deaerator, characterized in that, Include: Bottom plate (1), used to install the deaerator on the deck; The bracket (2) is fixedly mounted on the base plate (1); At least one membrane contactor (5) is fixedly mounted on the bracket (2). The membrane contactor (5) has a hollow cylindrical structure with a cavity inside. The membrane contactor (5) is provided with an inlet (11) and an outlet (12). The inlet (11) and the outlet (12) are both connected to the cavity. Hollow fiber (8) is disposed in the cavity. The hollow fiber (8) is made of hydrophobic fiber membrane filaments. An airflow channel is formed inside the hollow fiber (8). A baffle (7) is fixedly installed in the cavity, dividing the cavity into an inlet side chamber and an outlet side chamber along the water flow direction. The baffle (7) has several through holes for dividing the water flow in the inlet side chamber into multiple branches before flowing into the outlet side chamber. The diaphragm contactor (5) is also provided with an air extraction port (13) and an air inlet (14), both of which are connected to the airflow channel.

2. The marine low-energy boiler water deaeration device according to claim 1, characterized in that, The hollow fiber (8) is woven from hydrophobic fiber membrane filaments into a fabric, which is then wound into a columnar structure and placed inside the cavity.

3. The offshore low-energy boiler water deaeration device according to claim 2, characterized in that, The columnar structure of the hollow fiber (8) is disposed on the periphery of the cavity.

4. The offshore low-energy boiler water deaeration device according to claim 1, characterized in that, The inlet chamber is a water pipe (9) located on the side of the baffle (7) near the inlet (11), and the outlet chamber is a water collection pipe (10) located on the side of the baffle (7) near the outlet (12).

5. The offshore low-energy boiler water deaeration device according to claim 1, characterized in that, There are multiple membrane contactors (5), and all of the multiple membrane contactors (5) are arranged vertically on the bracket (2).

6. The offshore low-energy boiler water deaeration device according to claim 5, characterized in that, It also includes an inlet pipe (4) and an outlet pipe (6), all of the inlets (11) are connected to the inlet pipe (4), and all the outlets (12) are connected to the outlet pipe (6).

7. The offshore low-energy boiler water deaeration device according to claim 1, characterized in that, The air extraction port (13) is located at one end of the membrane contactor (5), and the air inlet (14) is located at the other end of the membrane contactor (5).

8. The offshore low-energy boiler water deaerator according to claim 1, characterized in that, The baffle (7) has several through holes located at the four edges of the baffle (7).

9. The marine low-energy boiler water deaeration device according to claim 1, characterized in that, The base plate (1) is also provided with a ladder (3), which is fixedly connected to the support (2).

10. The offshore low-energy boiler water deaeration device according to claim 1, characterized in that, The suction port (13) is used to connect to a vacuum pump, and the air inlet (14) is connected to the atmosphere.

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