Environment restoration system based on LNG-ORV cold drainage water and fishery breeding

Abstract

The invention provides an environment restoration system based on LNG-ORV cold drained water and fishery breeding. The environment restoration system comprises a reservoir, a seawater electrolysis module, an LNG-ORV gasification device, a central control unit, a multi-stage breeding workshop and a tail water treatment pond. The seawater electrolysis module is connected with the water storage tank, the water storage tank is connected with a water inlet of the LNG-ORV gasification device, a water outlet of the LNG-ORV gasification device is connected with a water inlet of the multi-stage culture workshop through a water inlet pipe, and a water outlet of the multi-stage culture workshop is connected with the tail water treatment tank; the water inlet pipe is provided with a residual chlorine detector and a temperature measurement and control instrument, and the residual chlorine detector, the temperature measurement and control instrument, the seawater electrolysis module and the LNG-ORV gasification device are electrically connected with the central control unit. According to the technical scheme, an LNG cold source is combined with fishery breeding, the cold energy resource of LNG is fully utilized, the breeding cost is reduced, and environment restoration is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection, and particularly to an environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture. Background Art

[0002] At present, with the rapid development of domestic LNG receiving stations, the gasification process of LNG is mainly completed through the ORV (open rack vaporizer) system. The working principle is to vaporize LNG by using the temperature difference of seawater circulation. A huge amount of cold seawater is generated during this gasification process, and the continuously low-temperature seawater is discharged into the offshore sea area, causing cold pollution to the sea area and harming the marine ecological environment.

[0003] Due to the attachment of marine organisms to the LNG gasification pipeline, the efficiency of the heat exchange interface will be reduced, and the pipeline is prone to blockage. To prevent this phenomenon, LNG receiving stations need to disinfect and kill marine organisms, especially attached organisms such as shellfish and their larvae. Currently, it is mainly implemented by electrolyzing seawater to generate hypochlorous acid. Although this killing method has good effects and no chemical residues, because hypochlorous acid has no selectivity in killing marine organisms, it leads to the imbalance and destruction of the marine biological ecosystem.

[0004] In addition, as a clean energy source with broad prospects, the cold energy contained in LNG is a new energy source with high value, which has not been effectively utilized at present and is wasted. Moreover, LNG companies also need to repair the pollution caused by this cold source. They not only need to pay additional ecological compensation funds, but also need to increase the pumping flow rate of seawater to control the discharge temperature of the cold drainage (the discharge temperature is required not to be lower than 5°C of the surrounding sea area), which increases the cost of LNG. Summary of the Invention

[0005] In view of the above technical problems, the present invention discloses an environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture, which makes full use of the cold source of LNG to repair the marine ecological environment and reduces the cost of LNG.

[0006] For this reason, the technical solution adopted by the present invention is as follows:

[0007] An environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture, comprising a reservoir for storing normal-temperature seawater, a seawater electrolysis module, an LNG-ORV gasification device, a central control unit, a multi-stage aquaculture workshop, and a tail water treatment pond; the seawater electrolysis module is connected to the reservoir, the reservoir is connected to the water inlet of the LNG-ORV gasification device, the water outlet of the LNG-ORV gasification device is connected to the water inlet of the multi-stage aquaculture workshop through a water inlet pipe, the water outlet of the multi-stage aquaculture workshop is connected to the tail water treatment pond, and the water in the tail water treatment pond is discharged into the sea; the water inlet pipe is provided with a residual chlorine detector and a temperature measurement and control instrument, and the residual chlorine detector, the temperature measurement and control instrument, the seawater electrolysis module, and the LNG-ORV gasification device are electrically connected to the central control unit.

[0008] Among them, the seawater electrolysis module is used to electrolyze seawater to obtain water containing hypochlorous acid, and then mix it with the seawater poured into the reservoir to obtain disinfected water; the LNG-ORV gasification device is used to perform heat and cold exchange on the disinfected water to obtain low-temperature seawater, and then transport it to the multi-stage aquaculture workshop. The central control unit adjusts the working parameters of the seawater electrolysis module according to the data fed back by the residual chlorine detector; the central control unit adjusts the working parameters of the LNG-ORV gasification device according to the data fed back by the temperature measurement and control instrument. An appropriate amount of hypochlorous acid can create a relatively sterile marine biological aquaculture water environment, and there is no need to add other antibiotics and harmful substances such as bactericides and disinfectants in the aquaculture system. The cold seawater discharged from LNG has become an excellent fish aquaculture water source. In the multi-stage aquaculture workshop, according to the sensitivity of various organisms to hypochlorous acid, the types of organisms to be cultured in each stage of aquaculture ponds can be set. Those that are more sensitive to the concentration of hypochlorous acid are placed in the latter-stage aquaculture ponds, and those with stronger tolerance to hypochlorous acid are placed in the former-stage aquaculture ponds. In this way, according to the differences in the tolerance of different varieties and specifications of aquaculture objects to the content of hypochlorous acid and temperature, the positions of the aquaculture ponds are set, and the cold drainage of LNG is matched with the varieties, specifications and aquaculture density of the aquaculture system, which can ensure biological safety.

[0009] In the above technical solution, during the operation of the LNG-ORV gasification device, most of the marine biological larvae are killed without selectivity, and the drastic change in temperature superimposes this killing effect. Because of the LNG-ORV system, problems of residual chlorine and low temperature in seawater occur. At this time, the seawater is a kind of seawater that has lost its activity. If it is directly discharged into nature, it will not only cause low-temperature pollution, but also lead to the structural imbalance of the biological community, and ultimately lead to the destruction or imbalance of the local marine ecosystem. The technical solution of the present invention can gradually restore the temperature of the low-temperature seawater and effectively release the residual chlorine in the seawater by setting multi-stage aquaculture ponds. The seawater discharged from the multi-stage aquaculture ponds has been greatly restored.

[0010] As a further improvement of the present invention, the multi-level aquaculture workshop includes a main water inlet pipe and a main water drain pipe. A plurality of aquaculture modules are connected in parallel between the main water inlet pipe and the main water drain pipe. Each aquaculture module includes at least a first aquaculture pond and a second aquaculture pond connected in series. The water inlet pipe is connected to the main water inlet pipe, and the main water drain pipe is connected to the tail water treatment pond.

[0011] As a further improvement of the present invention, the environmental restoration system based on LNG–ORV cold drainage and fishery aquaculture includes a seawater inlet pump. The inlet pipe of the seawater inlet pump extends into the seawater. The outlet pipe of the seawater inlet pump is connected to a reservoir and a seawater electrolysis module to pump seawater into the seawater electrolysis module and the reservoir. The seawater inlet pump is electrically connected to the central control unit and is controlled by the central control unit.

[0012] As a further improvement of the present invention, the water outlet of the LNG–ORV gasification device is connected to the water inlet pipe through a water transfer pump. The first aquaculture pond is used to culture lobsters, shellfish or scaled fish, and the second aquaculture pond is used to culture lobsters, shellfish, scaled fish or scaleless fish cultured in the first aquaculture pond.

[0013] As a further improvement of the present invention, the water inlet pipe is also provided with a detector for aquaculture biological condition parameters, which is electrically connected to the central control unit. The detector for aquaculture biological condition parameters detects the parameters in the water inlet pipe and feeds them back to the central control unit.

[0014] As a further improvement of the present invention, a seawater activation system based on the halophyte Sesuvium portulacastrum and the macroalgae Codium fragile is provided in the tail water treatment pond. The well-developed roots and rhizosphere microorganisms of Sesuvium portulacastrum are used to intercept, absorb and purify the suspended matter and absorb the residual chlorine in the aquaculture effluent. Codium fragile deeply absorbs the dissolved elements in the tail water to further repair the tail water environment. The well-developed roots of Sesuvium portulacastrum and the huge surface area of Codium fragile play a positive role in activating and repairing the microbial community in seawater. After detection, the main attached microorganisms in the final drainage of this system are close to 20% - 35% of those in the original water intake area, basically achieving the purpose of ecological restoration discharge.

[0015] The present invention also discloses an environmental restoration method based on the cold drainage of LNG–ORV and fishery farming. The environmental restoration system based on the cold drainage of LNG–ORV and fishery farming as described above is used to restore the environment, including the following steps: conveying seawater to a reservoir and a seawater electrolysis module, starting the seawater electrolysis module, and conveying the water containing hypochlorous acid generated by the seawater electrolysis module to the reservoir to obtain disinfected water; conveying the water in the reservoir to the LNG–ORV gasification device to obtain low-temperature seawater, and then conveying it to a multi-stage aquaculture workshop. The tail water of the multi-stage aquaculture workshop flows into the sea after passing through a tail water treatment pond; in the above process, the central control unit adjusts the working parameters of the seawater electrolysis module according to the data fed back by the residual chlorine detector; the central control unit adjusts the working parameters of the LNG–ORV gasification device according to the data fed back by the temperature measuring and controlling instrument.

[0016] As a further improvement of the present invention, according to the data fed back by the residual chlorine detector, the central control unit controls the seawater electrolysis module, and further controls the concentration of hypochlorous acid in the water inlet pipe to be 0.1 - 0.15 mg / L. Further, the concentration of hypochlorous acid in the water inlet pipe is controlled to be 0.1 - 0.15 mg / L.

[0017] As a further improvement of the present invention, according to the data fed back by the temperature measuring and controlling instrument, the central control unit controls the LNG–ORV gasification device, and further controls the water temperature in the water inlet pipe to meet the temperature requirements of the aquaculture organisms in the multi-stage aquaculture workshop.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] Adopting the technical solution of the present invention, the LNG cold source is combined with fishery farming. The seawater is electrolyzed by the seawater electrolysis module to obtain water containing hypochlorous acid, which is mixed with the water in the reservoir to obtain disinfected water with an appropriate concentration. The disinfected water passes through the LNG–ORV gasification device to obtain low-temperature disinfected water, which is used as the aquaculture water for the subsequent multi-stage aquaculture workshop. This aquaculture water has a bactericidal effect and is beneficial to aquaculture. By controlling the hypochlorous acid content, temperature, and aquaculture system parameters of the low-temperature disinfected water through a residual chlorine detector, a temperature measuring and controlling instrument, a central control unit, etc., it can ensure that the aquaculture reaches the optimal production under the normal operation of LNG. In the multi-stage aquaculture workshop, through the open-gradient aquaculture layout of different varieties, the temperature of the cold drainage gradually increases, and finally it is discharged into the sea when it is close to the temperature of natural seawater (within a temperature difference of 1.5 °C), avoiding the formation of a cold water mass in the drainage area. This technical solution makes full use of the cold energy resources of LNG, reduces the aquaculture cost by about 30%, has significant aquaculture energy-saving and emission-reduction effects, and with the help of the strong stability of the LNG system, it can achieve the purpose of automatic control operation of the aquaculture system. Description of the Drawings

[0020] Figure 1It is a schematic structural diagram of an environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture according to an embodiment of the present invention. Detailed implementation manners

[0021] The following further elaborates on the preferred embodiments of the present invention.

[0022] As Figure 1 shown, an environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture includes a pump house, a reservoir for storing normal-temperature seawater, a seawater electrolysis module, an LNG-ORV gasification device, a central control unit, a multi-stage aquaculture workshop, and a tail water treatment pond; the pump house is provided with a plurality of seawater inlet pumps, and the plurality of seawater inlet pumps are connected to the reservoir and the seawater electrolysis module for pumping seawater into them. The seawater electrolysis module is connected to the reservoir, the reservoir is connected to the water inlet of the LNG-ORV gasification device, the water outlet of the LNG-ORV gasification device is connected to the water inlet of the multi-stage aquaculture workshop through a water inlet pipe, the water outlet of the multi-stage aquaculture workshop is connected to the tail water treatment pond, and the water in the tail water treatment pond is discharged into the sea; the water inlet pipe is provided with a residual chlorine detector and a temperature control detector, and the residual chlorine detector, the temperature control detector, the seawater electrolysis module, and the LNG-ORV gasification device are electrically connected to the central control unit. The water outlet of the LNG-ORV gasification device is connected to the water inlet pipe through a water transfer pump. Further, the water inlet pipe is also provided with a culture biological condition parameter detector, and the culture biological condition parameter detector is electrically connected to the central control unit. The culture biological condition parameter detector detects the parameters in the water inlet pipe and feeds them back to the central control unit.

[0023] The multi-stage aquaculture workshop includes a water inlet main pipe and a water drainage main pipe, and a plurality of aquaculture modules are connected in parallel between the water inlet main pipe and the water drainage main pipe. Each aquaculture module includes at least a first aquaculture pond and a second aquaculture pond connected in series. The water inlet pipe is connected to the water inlet main pipe, and the water drainage main pipe is connected to the tail water treatment pond.

[0024] Preferably, the first aquaculture pond raises lobsters, shellfish or scaled fish, and the second aquaculture pond raises lobsters, shellfish, scaled fish or scaleless fish raised in the first aquaculture pond.

[0025] The pump house is provided with a plurality of seawater inlet pumps. The seawater inlet pumps are used to pump seawater into the seawater electrolysis module and the reservoir. The seawater electrolysis module electrolyzes the seawater to obtain water containing hypochlorous acid, which flows into the reservoir and is mixed to obtain disinfected water with an appropriate hypochlorous acid concentration.

[0026] Furthermore, the tailwater treatment pool is equipped with a seawater activation system with halophyte seahorses and large algae spinulosa as the matrix, using the well-developed root system and rhizosphere microorganisms of seahorses to intercept suspended solids, absorb and purify the aquaculture discharge water, and absorb residual chlorine. The spinulosa deeply absorbs the soluble elements in the tailwater, further repairing the tailwater environment. The well-developed root system of seahorses and the huge surface area of ​​spinulosa have a positive effect on the activation and repair of microbial communities in seawater. According to the test, the final drainage of this system is close to 20% to 35% of the main attached microorganisms in the original water intake area, basically achieving the purpose of ecological restoration discharge.

[0027] The method for repairing LNG seawater using the above-mentioned repair system includes the following steps: transporting seawater to a water reservoir and a seawater electrolysis module, turning on the seawater electrolysis module, and transporting water containing hypochlorous acid produced by the seawater electrolysis module to a water reservoir to obtain disinfected water; transporting water in the water reservoir to an LNG-ORV gasification device to obtain low-temperature seawater, and then transporting it to a multi-stage breeding workshop, and the tail water of the multi-stage breeding workshop flows into the sea after passing through a tailwater treatment tank; in the above process, the central control unit adjusts the working parameters of the seawater electrolysis module according to the data fed back by the residual chlorine detector; the central control unit adjusts the working parameters of the LNG-ORV gasification device according to the data fed back by the temperature measurement and control instrument. Specifically, according to the data fed back by the residual chlorine detector, the central control unit controls the concentration of hypochlorous acid in the water inlet pipe to be 0.1-0.15 mg / L by controlling the seawater electrolysis module. Further, the concentration of hypochlorous acid in the water inlet pipe is controlled to be 0.1-0.15 mg / L. According to the data fed back by the temperature measuring and controlling instrument, the central control unit controls the water temperature in the water inlet pipe by controlling the LNG-ORV gasification device to meet the temperature requirements of the cultured organisms in the multi-stage culture workshop.

[0028] The above system is used in the Dapeng LNG receiving station, and the seawater is disinfected by electrolyzing seawater to generate trace amounts of sodium chlorate, which does not add any chemical substances when it returns to the ocean. As a universal drinking water disinfectant, the sodium hypochlorite produced by electrolysis has excellent elimination effects on pathogens such as fish parasites, Staphylococcus aureus, Escherichia coli, and Salmonella. After natural volatilization in the open channel of seawater and aeration treatment of the aquaculture system, the residual chlorine concentration of the aquaculture water is generally around 0.1-0.15 mg / L, which is much lower than the residual chlorine content of 0.7 mg / L in Shenzhen's drinking water (see "Shenzhen Water Bureau Water Quality Bulletin"). The pure and healthy water quality provides an almost sterile growth environment for fish, and no fish medicine needs to be added, making the quality healthier. This technical solution makes full use of the cold source of LNG to repair the marine ecological environment, reducing the cost of aquaculture and the cost of LNG paid for environmental repair.

[0029] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. An environmental remediation system based on LNG-ORV cold drainage and fishery aquaculture, characterized by: It includes a water reservoir for storing normal temperature seawater, a seawater electrolysis module, an LNG-ORV gasification device, a central control unit, a multi-stage breeding workshop, and a tailwater treatment tank; the seawater electrolysis module is connected to the water reservoir, the water reservoir is connected to the water inlet of the LNG-ORV gasification device, the water outlet of the LNG-ORV gasification device is connected to the water inlet of the multi-stage breeding workshop through an inlet pipe, the water outlet of the multi-stage breeding workshop is connected to the tailwater treatment tank, and the water in the tailwater treatment tank is discharged to the sea; the water inlet pipe is provided with a residual chlorine detector and a temperature measurement and control instrument, and the residual chlorine detector, the temperature measurement and control instrument, the seawater electrolysis module, the LNG-ORV gasification device and the central control unit are electrically connected.

2. The environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture according to claim 1 is characterized by: The multi-stage breeding workshop includes an inlet main pipe and a drainage main pipe, and multiple breeding modules are connected in parallel between the inlet main pipe and the drainage main pipe. Each breeding module includes at least a first breeding pond and a second breeding pond connected in series. The inlet pipe is connected to the inlet main pipe, and the drainage main pipe is connected to the tailwater treatment tank.

3. The environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture according to claim 2 is characterized by: It comprises a seawater inlet pump, the inlet pipe of which extends into the seawater, the outlet pipe of which is connected to a water reservoir and a seawater electrolysis module; and the seawater inlet pump is electrically connected to a central control unit.

4. The environmental restoration system based on LNG-ORV cold drainage and fishery aquaculture according to claim 2 is characterized by: The water outlet of the LNG-ORV gasification device is connected to the water inlet pipe through a water pump; the first breeding pond breeds lobsters, shellfish or scaled fish, and the second breeding pond breeds lobsters, shellfish, scaled fish or scaleless fish in the first breeding pond.

5. Environmental remediation method based on LNG-ORV cold drainage and fishery aquaculture, characterized by: The environment is repaired by using the environmental restoration system based on LNG-ORV cold drainage and fishery farming as described in any one of claims 1 to 4, comprising the following steps: transporting seawater to a water reservoir and a seawater electrolysis module, starting the seawater electrolysis module, and transporting water containing hypochlorous acid generated by the seawater electrolysis module to the water reservoir to obtain disinfected water; transporting water in the water reservoir to an LNG-ORV gasification device to obtain low-temperature seawater, which is then transported to a multi-stage breeding workshop, and the tail water of the multi-stage breeding workshop flows into the sea after passing through a tail water treatment tank; in the above process, the central control unit adjusts the working parameters of the seawater electrolysis module according to the data fed back by the residual chlorine detector; the central control unit adjusts the working parameters of the LNG-ORV gasification device according to the data fed back by the temperature measurement and control instrument.

6. The environmental remediation method based on LNG-ORV cold drainage and fishery aquaculture according to claim 5 is characterized by: According to the data fed back by the residual chlorine detector, the central control unit controls the seawater electrolysis module to control the concentration of hypochlorous acid in the water inlet pipe to 0.1-0.15 mg / L.

7. The environmental remediation method based on LNG-ORV cold drainage and fishery aquaculture according to claim 6 is characterized by: Control the concentration of hypochlorous acid in the water inlet pipe to 0.1-0.15 mg / L.

8. The environmental remediation method based on LNG-ORV cold drainage and fishery aquaculture according to claim 5 is characterized by: According to the data fed back by the temperature measuring and controlling instrument, the central control unit controls the water temperature in the water inlet pipe by controlling the LNG-ORV gasification device to meet the temperature requirements of the cultured organisms in the multi-stage culture workshop.

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