Biological adhesion prevention system of LNG receiving station long-distance seawater taking system

Abstract

According to the biological adhesion prevention system of the long-distance seawater intake system of the LNG receiving station, a water intake forebay is connected with a water intake through a water intake pipe culvert, a medicine preparation room is connected with a medicine adding branch pipe A through a medicine adding pipe, and the medicine adding branch pipe A is of a dispersed medicine adding structure composed of a plurality of first-stage branch pipes and a plurality of second-stage branch pipes. The technology is based on the principle of highlighting key points and fully covering, the key points are that antifouling paint is coated on the surface of an area where organisms are easy to adhere in a water taking system, so that fouling organisms are prevented from adhering and growing, and meanwhile, an antifouling agent (biocide) is added into seawater in a combined manner, so that organisms in the seawater are killed or the growth of the organisms is inhibited; therefore, the purpose of comprehensively preventing organisms from adhering and growing is achieved, and normal operation of a long-distance seawater taking system is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of seawater industrial cooling water, in particular to an anti-biological attachment technology for a long-distance seawater intake system of an LNG receiving station. Background Art

[0002] LNG receiving stations consume significant energy to vaporize natural gas. Extracting heat from seawater to vaporize natural gas is an energy-efficient and environmentally friendly energy source. With increasing market demand for liquefied natural gas (LNG), LNG receiving stations are continuously expanding, resulting in long-distance seawater intake. Long-distance seawater intake systems are more susceptible to biofouling from the seawater environment due to the length of the intake pipelines.

[0003] In the seawater intake systems of LNG receiving stations, biofouling is a significant problem. Over long-term marine operations, marine organisms such as shellfish, algae, and other microorganisms gradually attach and grow on the inner surfaces of intake system pipes or culverts. This can lead to obstruction of grate screens, reduction in pipe diameter, increased flow resistance, and even blockage in severe cases, disrupting the normal operation of the entire system. Biofouling also increases system maintenance costs. Therefore, regular manual cleaning of pipes or culverts is required, but this is inefficient. To reduce labor costs, chemical dosing systems can be added to the intake pipes or culverts. Chlorine produced by electrolyzing seawater is then introduced into the intake pipes to inhibit the growth of marine organisms. However, existing dosing systems still pose a significant risk of biofouling in the pipes and culverts. Furthermore, current LNG receiving stations often only have residual chlorine monitoring devices installed at the outlets, lacking corresponding online monitoring devices for the intake system. This makes it difficult to monitor the chemical concentration in the intake system. Summary of the Invention

[0004] In response to the above problems, the utility model provides an anti-biological attachment system for the long-distance seawater intake system of an LNG receiving station. This technology is based on the principle of highlighting key points and comprehensive coverage. It focuses on applying anti-fouling paint on the surface of areas in the water intake system where biological attachment is likely to occur to prevent the attachment and growth of fouling organisms. At the same time, antifouling agents (biocides) are added to the seawater to kill organisms in the seawater or inhibit their growth, thereby achieving the purpose of comprehensive prevention of biological attachment and growth, and ensuring the normal operation of the long-distance seawater intake system.

[0005] To achieve the above objectives, the present invention provides the following technical solutions:

[0006] An anti-fouling system for a long-distance seawater intake system at an LNG receiving station. The intake forebay is connected to the water intake via a culvert, and the pharmaceutical room is connected to a dosing branch pipe A via a dosing pipe. Dosing branch pipe A comprises a distributed dosing structure consisting of several primary and secondary branches. Dosing branch pipe A dispenses chemicals parallel to the intake grating surface and perpendicular to the extension line of the culvert. This distributed dosing structure, formed by the secondary branches, evenly distributes the antifouling agent across the entire cross-section of the intake. Seawater containing the antifouling agent flows evenly through the intake grating and the entire inner wall of the culvert, eliminating areas of noticeable antifouling agent deficiency in the water intake system and enhancing the effectiveness of the antifouling agent.

[0007] Inside the water intake, a grille is installed inside the dosing branch pipe A. The dosing branch pipe A is placed on the seaward side of the water intake grille, extending a certain distance beyond the grille. When biocide is added, the liquid diffuses with the water flow to the grille surface, preventing the growth of organisms on the grille and other surfaces of the water intake system.

[0008] A working well is located on the intake culvert between the forebay and the intake. A dosing branch pipe B is installed within the working well and connected to the dosing pipe. The dosing port of dosing branch pipe B within the working well is perpendicular to the extension line of the intake culvert. During construction, the working well is primarily used to position jacking equipment and splice jacking pipes. During operation, it is primarily used to install the dosing branch pipe and to troubleshoot and inspect underground pipelines to ensure their proper operation.

[0009] An online monitor is installed in the water intake forebay. This monitor is a residual chlorine online monitor that can monitor the residual biocide content in seawater in real time, preventing insufficient biocide addition from affecting the effectiveness of preventing biofouling growth. It also prevents excessive biocide addition from causing excessive residual chlorine content in the discharged seawater, which could cause environmental pollution.

[0010] The grille surface is coated, from the inside out, with the following: primer, tie coat, and antifouling paint. The antifouling paint is a low-surface-energy antifouling paint, such as a low-surface-energy fluorocarbon antifouling paint, or a self-polishing antifouling paint with a trace amount of antifouling agent added, such as a self-polishing silicone antifouling paint. The antifouling paint maintains its antifouling properties for an extended period of time, effectively preventing the growth of organisms in marine environments. The tie coat is an epoxy tie coat, such as International Paint's FAJ034 / 262, which primarily enhances the bonding between antifouling paint coatings.

[0011] Advantages of utility models

[0012] 1. The utility model applies antifouling paint on the surface of the areas of the water intake system that are susceptible to biological attachment, which can effectively reduce the attachment and growth of marine organisms in these areas, and play a role in strengthening the prevention of biological attachment and growth.

[0013] 2. The present invention retains the traditional method of adding biocides to prevent biological attachment and growth, but in terms of the arrangement of the dosing port, the dosing port is placed a certain distance beyond the water intake grille, so that the drug solution diffuses with the seawater to the water intake grille, achieving the effect of preventing biological attachment in the water intake system including the water intake grille.

[0014] 3. The innovation of this utility model lies in the integration of the technical advantages of coating antifouling and chemical antifouling, which effectively solves the problem of biological attachment in long-distance seawater intake systems. The coating antifouling can strengthen the effect of preventing biological attachment and growth in areas susceptible to biological attachment, while the chemical antifouling can achieve a comprehensive antifouling effect.

[0015] 4. The utility model only applies antifouling paint on the surface of the water intake system in areas susceptible to the attachment and growth of marine organisms. Compared with the method of applying antifouling paint on the entire surface, the initial investment is lower and the maintenance frequency and maintenance cost of the water intake system can be reduced.

[0016] 5. The utility model adjusts the dosage of biocide in the water intake system in real time through online monitoring, which can effectively avoid the problem of insufficient biocide addition to achieve the effect of preventing biological attachment and growth. It also avoids the risk of excessive addition of biocide causing the residual chlorine content in the discharged seawater to exceed the standard, thereby creating the risk of environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the connection relationship of the utility model;

[0018] Figure 2 Schematic diagram of the water intake structure of the utility model;

[0019] The serial numbers in the figure are marked as follows: 1-dosing pipe; 11-dosing branch pipe A; 12-dosing branch pipe B; 2-pharmacy room; 3-water intake culvert; 4-water intake; 41-grid; 6-working well; 7-water intake forebay; 71-online monitor. DETAILED DESCRIPTION Example 1

[0020] An anti-biological attachment system for a long-distance seawater intake system at an LNG receiving station. The intake forebay 7 is connected to the water intake 4 via an intake culvert 3. The pharmaceutical room 2 is connected to the dosing branch pipe A11 via a dosing pipe 1. The dosing branch pipe A11 is a dispersed dosing structure consisting of several primary branch pipes and several secondary branch pipes.

[0021] In the water intake 4, a grid 41 is provided on the inner side of the dosing branch pipe A11.

[0022] A working well 6 is provided on the water intake culvert 3 between the water intake forepool 7 and the water intake 4 , and a dosing branch pipe B12 is provided in the working well 6 , and the dosing branch pipe B12 is connected to the dosing pipe 1 .

[0023] An online monitor 71 is provided in the water intake forepool 7 .

[0024] The surface of the grid 41 is coated in sequence from the inside to the outside: primer, tie paint and antifouling paint.

Claims

1. An anti-biological attachment system for a long-distance seawater intake system at an LNG receiving station, characterized in that: The water intake forepool (7) is connected to the water intake (4) through the water intake culvert (3), and the pharmaceutical room (2) is connected to the dosing branch pipe A (11) through the dosing pipe (1). The dosing branch pipe A (11) is a dispersed dosing structure composed of several primary branch pipes and several secondary branch pipes. In the water intake (4), a grid (41) is provided on the inner side of the dosing branch pipe A (11); A working well (6) is provided on the water intake culvert (3) between the water intake forepool (7) and the water intake (4), a dosing branch pipe B (12) is provided in the working well (6), and the dosing branch pipe B (12) is connected to the dosing pipe (1).

2. The anti-biological attachment system of the long-distance seawater intake system of the LNG receiving station according to claim 1 is characterized in that: An online monitoring instrument (71) is provided in the water intake forepool (7).

3. The anti-biological fouling system of the long-distance seawater intake system of the LNG receiving station according to claim 1 is characterized in that: The surface of the grid (41) is coated in sequence from the inside to the outside: primer, connecting paint and antifouling paint.

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