JP2016120445A - Method for inhibiting swimming of marine organisms, and system and method for suppressing adhesion of marine organisms - Google Patents

Abstract

Provided are a method for effectively inhibiting the swimming of marine organisms and a system and method for suppressing the attachment of marine organisms in a seawater intake channel from the sea and a seawater discharge channel to the sea. In a method for inhibiting the swimming of marine organisms by bringing the nanobubbles into contact with marine organisms, the nanobubbles are generated after the microbubbles are generated in the first water having a salt concentration of 0.5% by weight or more. A method using microbubble-containing water produced by adding second water having a salt concentration of 0.5 wt% or more within minutes. [Selection figure] None

Description

  The present invention relates to a method for inhibiting swimming of marine organisms and a system and method for suppressing adhesion of marine organisms.

In power plants such as thermal power plants and nuclear power plants that use seawater as cooling water, intake water that takes seawater from the sea and supplies it to the condenser, and discharges seawater that passes through the condenser to the sea Marine organisms such as barnacles and mussels are likely to adhere to the inside of the spillway. When the adhesion amount of marine organisms increases, there is a risk of causing problems such as blocking the cooling water flow path and reducing cooling performance. Therefore, conventionally, for example, as disclosed in Patent Documents 1 to 5, by injecting a chlorine-based chemical such as sodium hypochlorite solution or chlorine dioxide into the cooling water, Inhibition of adhesion is performed. Further, by dissolving carbon dioxide microbubbles (hereinafter referred to as CO ₂ microbubbles) (for example, see Patent Document 6) and nanobubbles (hereinafter referred to as CO ₂ nanobubbles) (for example, see Patent Document 7) in cooling water. A method for suppressing the adhesion of marine organisms to the cooling water channel has been reported.

JP-A-7-265867 Japanese Patent Laid-Open No. 11-37666 JP-A-2005-144212 JP 2005-144213 A JP 2005-244214 A JP 2010-43060 A JP 2012-206099 A

  An object of the present invention is to provide a method for inhibiting swimming of marine organisms and a system and method for suppressing adhesion of marine organisms.

  One embodiment of the present invention is a method for inhibiting the swimming of marine organisms, comprising the step of bringing nanobubbles into contact with the marine organisms, wherein the nanobubbles are first water having a salinity of 0.5% by weight or more. This is a method produced by adding second water having a salt concentration of 0.5% by weight or more within 5 minutes after starting to generate microbubbles. The water may be produced by adding the second water within 3 minutes after starting to generate microbubbles in the first water. The water may be diluted 1.5 times or more by adding the second water to the first water. The first water and / or the second water may be seawater. The gas for generating the microbubbles may be carbon dioxide. The marine organisms may be barnacle larvae.

The nanobubbles may have a particle size of 1 to 999 nm.

  Another embodiment of the present invention is a system that suppresses the attachment of marine organisms to the heat exchange water flow path, the supply device for supplying water containing the marine organisms to the heat exchange target equipment, Using the supplied heat exchange water, a heat exchanger for exchanging heat with the heat exchange target equipment, and for discharging water after heat exchange with the heat exchange target equipment from the heat exchange target equipment A discharge device, an injection device for injecting water containing nanobubbles into any one or more of water containing the marine organisms, the supplied water, and the heat exchange target equipment and water after heat exchange The water containing the nanobubbles is a second water having a salt concentration of 0.5% by weight or more within 5 minutes from the start of generating microbubbles in the first water having a salt concentration of 0.5% by weight or more. Made by adding water.

  A further embodiment of the present invention is a method for suppressing the attachment of marine organisms to a heat exchange water flow path, the step of supplying water containing marine organisms to a heat exchange target facility, and the supplied water The step of exchanging heat with the heat exchange target equipment, the step of releasing the heat exchange target equipment and water after heat exchange from the heat exchange target equipment, the water containing the marine organisms, the supply And a step of injecting water containing nanobubbles into any one or more of the heat exchange target equipment and water after heat exchange, and the water containing nanobubbles has a salt concentration of 0.5. It was produced by adding the second water having a salinity of 0.5% by weight or more within 5 minutes from the start of generating microbubbles in the first water by weight.

  According to the present invention, it is possible to provide a method for inhibiting swimming of marine organisms and a system and method for suppressing adhesion of marine organisms.

It is a figure which shows the whole structure of the system which suppresses adhesion of the marine organism to the heat exchange water flow path demonstrated as one Embodiment of this invention. It is a figure which shows typically the heat exchange water flow path which consists of a water intake channel, a water discharge channel, an LNG vaporizer flow path, and a condenser flow path in one Embodiment of this invention. It is a figure which shows the detailed structure of the nano bubble injection apparatus in one Embodiment of this invention. It is a figure which shows the structural example of the injection port with which an injection tube is provided in one Embodiment of this invention. It is a figure which shows another structural example of the injection port with which an injection pipe is provided in one Embodiment of this invention. In one embodiment according to the present invention, an ESR spectrum of the samples diluted five-fold seawater containing CO ₂ microbubbles immediately after stopping the microbubble generator. In one embodiment according to the present invention, an ESR spectrum of a sample of 2 minutes elapsed artificial seawater from the start to generate CO ₂ microbubbles in water and diluted 5-fold. In one embodiment according to the present invention, an ESR spectrum of a sample of one minute elapsed artificial seawater from the start to generate CO ₂ microbubbles in water for 2 minutes. In one embodiment according to the present invention, is a graph showing the results of examining the paralysis of larvae occurs when contacting the CO ₂ nanobubbles in Akafujitsubo-nauplii late larval. In one embodiment according to the present invention, the Akafujitsubo-nauplius late larval is a graph showing the results of examining the paralysis of larvae occurs when contacting the CO ₂ nanobubbles was allowed to stand a certain time after fabrication.

  Hereinafter, embodiments of the present invention completed based on the above knowledge will be described in detail with reference to examples. The objects, features, advantages, and ideas of the present invention will be apparent to those skilled in the art from the description of the present specification, and those skilled in the art can easily reproduce the present invention from the description of the present specification. it can. The embodiments and specific examples of the invention described below show preferred embodiments of the present invention, and are shown for illustration or explanation. It is not limited. It will be apparent to those skilled in the art that various modifications and variations can be made based on the description of the present specification within the spirit and scope of the present invention disclosed herein.

== Method for producing nanobubbles ==
The water containing nanobubbles used in the present invention has a second concentration of 0.5% by weight or more within 5 minutes from the start of generation of microbubbles in the first water having a salt concentration of 0.5% by weight or more. It can be produced by adding water.

  A microbubble is a bubble having a diameter of 50 μm or less, and can be generated using a known microbubble generator using a two-phase flow swirling method or a pressure dissolution method. In a known two-phase flow swirl device, a vortex having a radius of 10 cm or less is forcibly generated in a gas-liquid mixture containing a gas to be contained in a microbubble by using a rotor, etc. By striking against obstacles and fluids having different relative velocities, the gas components acquired in the vortex can be dispersed along with the disappearance of the vortex, and microbubbles can be generated. In addition, in the pressure dissolution type apparatus, after the gas contained in the microbubbles is dissolved in water under a high pressure of 2 atm or higher, the dissolved gas becomes supersaturated by releasing the water to atmospheric pressure. . When a large number of vortices having a radius of 1 mm or less are generated using a water flow and obstacles at a pressure release location, a large number of bubble nuclei are formed due to molecular fluctuations of water in the central region of the vortex flow, Along with the supersaturation condition, the gas component in the water diffuses toward these bubble nuclei and the bubble nuclei grow to produce microbubbles. The microbubbles generated by these methods have a particle size of 50 μm or less, and a particle size peak at 10 to 15 μm when measured with a laser light blocking liquid particle counter (for example, LiQuilaz-E20 manufactured by SPM). The number of microbubbles in the peak region is 1000 / mL or more (see JP 2000-51107 A; JP 2003-265938 A, etc.). Here, the gas for generating the microbubbles is not particularly limited, and examples thereof include air, oxygen, ozone, carbon dioxide, and nitrogen.

  Microbubbles, which are small bubbles, have a slow ascent rate in water, a large specific surface area, and the gas contained therein is pressurized by the magnitude of the pressure obtained by the Young-Laplace equation due to the effect of surface tension. Yes. For this reason, the gas is efficiently dissolved in water in the form of microbubbles, but the microbubbles shrink in water over time. Although there are some differences depending on the environmental conditions, microbubbles in water usually dissolve completely and disappear within 3 minutes. However, when microbubbles are generated in water with a salinity of 0.5% by weight or more, the concentration of ions increases around the bubbles in the process of contracting the microbubbles. The gas contained therein may be prevented from dissolving in water, and as a result, some of the generated microbubbles are stabilized in a miniaturized state. Thus, the inventors of the present application have found that nanobubbles, which are bubbles having a diameter of 50 to 500 nm, are generated in water and exist stably in a temporary manner.

  However, the number of nanobubbles generated in water is generally small. The microbubbles generated in the water rapidly shrink as described above. However, in this process, since the concentration of the gas dissolved in the water increases rapidly, the gas concentration gradient near the gas-liquid interface decreases, and the dissolution rate decreases. As a result, the reduction speed of the microbubbles also decreases, and it becomes difficult for ions to concentrate at the gas-liquid interface. As a result, although the lifetime as a microbubble becomes somewhat long, the situation where it remains as a nanobubble for a long time is not formed. As described above, in order to generate a large amount of nanobubbles in a certain amount of water, it is necessary to continuously supply microbubbles in the water. The number of occurrences is significantly reduced.

  The present invention utilizes the physical properties of the microbubbles generated in the water containing the electrolyte ions, and specifically, within 5 minutes, preferably within 5 minutes, while the microbubbles shrinkage rate decreases after the microbubbles are generated in the water. Within 3 minutes, water having a salinity of 0.5% by weight or more is added to the water in which microbubbles are generated, and the concentration of the gas dissolved in the water is lowered. As a result, the gas concentration gradient in the vicinity of the gas-liquid interface is restored, so that the gas molecules contained in the microbubbles are efficiently dissolved again in water, and the microbubbles are rapidly reduced again. As a result, under the condition where water with a salt concentration of 0.5% by weight or more is not added, only some floating microbubbles can remain as nanobubbles, creating an environment where a much larger number of microbubbles can remain as nanobubbles. As a result, the number of nanobubbles generated in water increases. When 5 minutes have passed since the generation of microbubbles in the water, the microbubbles have finished shrinking and the microbubbles have disappeared, so even if water with a salt concentration of 0.5% by weight or more is added, nanobubbles are generated. I can't let you. Therefore, when microbubbles are continuously generated in water, in order to maintain a large number of nanobubbles at all times, the addition of water having a salt concentration of 0.5% by weight or more can be performed continuously or intermittently ( (For example, once every 5 minutes).

  In the present invention, the salt concentration of water used for generating microbubbles and water used for adding to the water generating microbubbles may be the same or different, and is 0.5 wt%. Preferably, it is preferably 1% by weight or more, more preferably 2% by weight or more. The upper limit of the salt concentration is not particularly limited, but is preferably 10% by weight or less and more preferably 5% by weight or less in view of cost. The amount of water having a salt concentration of 0.5% by weight or more added to the water in which microbubbles are generated is not particularly limited, but is preferably equal to or more than the amount of water in which microbubbles are generated, and more than 3 times the amount. Desirably 5 times or more is more desirable. Water having a salt concentration of 0.5% by weight or more can be prepared by dissolving the salt in water such as distilled water. The kind of salt is not particularly limited, and examples thereof include sodium chloride, potassium chloride, magnesium chloride, and calcium chloride. Natural water or artificial seawater having a salinity of about 3.5% by weight may be used as the water having a salinity of 0.5% by weight or more. The pH of water having a salt concentration of 0.5% by weight or more is not particularly limited, but may be adjusted as appropriate according to the type of gas for generating microbubbles.

  In this way, water containing a large number of nanobubbles can be produced easily and at low cost. In general, when water containing a certain substance is diluted, the concentration of the substance decreases in inverse proportion to the degree of dilution. It is a surprising fact that the number of nanobubbles generated in water can be increased by diluting the water with a second water having a salt concentration of 0.5% by weight or more.

  Nanobubbles produced by the method of the present invention can be used for applications depending on the type of gas contained in the nanobubbles. Since the effect of nanobubbles is proportional to the number of nanobubbles contained in the water, the water containing nanobubbles produced by the method of the present invention is more effective than the water containing nanobubbles produced by the existing method. Large number, high effect.

== Method to inhibit swimming of marine life ==
The method for inhibiting the swimming of marine organisms according to the present invention includes the step of bringing the nanobubbles produced by the above method into contact with marine organisms. The gas for generating the nanobubbles is preferably carbon dioxide.

  Here, the method of bringing nanobubbles into contact with marine organisms is not particularly limited, and nanobubbles may be generated with water containing marine organisms, or water containing nanobubbles produced separately may be added to water containing marine organisms. .

  The nanobubble here refers to a bubble having a particle size of 1 nm to 999 nm. The particle size is preferably 10 to 900 nm, more preferably 40 to 480 nm, and still more preferably 300 to 410 nm. By bringing marine organisms into contact with water containing nanobubbles having such a particle size, it is possible to more effectively inhibit marine organisms from swimming.

  The kind of marine organisms is not particularly limited, and for example, shellfish such as barnacles and mussels may be used, but barnacle larvae, particularly adhering larvae are preferred.

  Thus, by bringing marine organisms into contact with water containing nanobubbles, marine organisms contained in the injected water can be paralyzed, and as a result, marine organisms can be inhibited from swimming.

  If the swimming of marine organisms is inhibited, for example, marine organisms can be prevented from adhering to a water container containing marine organisms, and marine organisms can be easily recovered and removed from the water. In addition, since adhesion is a phenomenon accompanied by a form change called metamorphosis, under an environment where a certain percentage of individuals are paralyzed, it is considered that almost all individuals are highly likely to avoid adhesion.

== System configuration for suppressing the attachment of marine organisms to the heat exchange water flow path ==
FIG. 1 is a diagram illustrating an overall configuration of a system that suppresses the attachment of marine organisms to a heat exchange water flow path, which will be described as an embodiment of the present invention. As shown in FIG. 1, a system (hereinafter simply referred to as “system”) 100 that suppresses the attachment of marine organisms to a heat exchange water channel is a thermal power plant 10 constructed on a site facing the sea 2. Prepare. The thermal power plant 10 includes a fuel storage facility 12, an LNG tank 14, a power generation facility 16, an LNG vaporizer 17, a water intake channel 20, a water discharge channel 22, and the like.

  The power generation facility 16 further includes condensers 18A and 18B. The condensers 18 </ b> A and 18 </ b> B are devices that are connected to a steam prime mover to condense water vapor and create a high vacuum to assist the expansion action of the steam. In order to cool and condense water vapor in the condensers 18A and 18B, the condensers 18A and 18B include condenser flow paths 29A and 29B as heat exchange water flow paths through which the cooling water passes. Note that, as the condensers 18A and 18B, surface condensers in which cooling water passes through the condenser flow paths 29A and 29B are illustrated, but the cooling water is directly introduced into the condenser, It may be a direct contact condenser that mixes steam with steam.

  The LNG vaporizer 17 is an apparatus that vaporizes LNG (liquefied natural gas) by heat exchange. In order to heat and vaporize LNG in the LNG vaporizer 17, the LNG vaporizer 17 further includes an LNG vaporizer flow path 27 as a heat exchange water flow path through which water serving as a heating heat source passes.

  The intake channel 20 is a channel for supplying the water for heat exchange that has been taken into the heat exchange target facility. The intake channel 20 further includes an intake port 24 for taking water. The intake channel 20 takes in seawater containing marine organisms from the sea 2 through the intake port 24, and cools the condensers 18A and 18B, which are heat exchange target equipment, from the seawater thus taken. Supply to condenser channels 29A and 29B.

  Here, the heat exchange target equipment is not particularly limited, but may be, for example, a condenser or an LNG vaporizer provided in a power plant such as a thermal power plant.

  The water discharge path 22 is a flow path for discharging water after heat exchange with the heat exchange target equipment to the outside of the heat exchange target equipment. The water discharge channel 22 further includes a discharge port 26 for discharging the water after heat exchange to the sea. That is, the water discharge channel 22 discharges the seawater flowing through the condenser channels 29A and 29B heated by heat exchange with the condensers 18A and 18B to the sea through the discharge port 26.

  In the present embodiment, a part of the water discharge channel 22 leads to the LNG vaporizer channel 27 in order to effectively use the seawater heated by the condensers 18A and 18B. Thereby, since the seawater heated by the condensers 18A and 18B is sent to the LNG vaporizer 17, the LNG vaporizer 17 is heated using the heat generated by the condensers 18A and 18B. be able to. Seawater flowing through the LNG vaporizer flow path 27 after heat exchange with the LNG vaporizer 17 joins the water discharge path 22. The water discharge channel 22 discharges the seawater flowing inside the merged LNG vaporizer flow channel 27 to the sea through the discharge port 26.

  As described above, since the seawater flows through the intake channel 20, the discharge channel 22, the LNG vaporizer channel 27, and the condenser channels 29A and 29B, which are heat exchange channels, the inside of the heat exchange channel , It is easy for marine organisms such as shellfish to attach and propagate. If a large amount of marine organisms adhere to the heat exchange water flow path, the heat exchange function may be deteriorated because the flow path is blocked and a sufficient flow rate cannot be obtained.

  In particular, with regard to the intake channel 20, the intake channel 20 is very far away from the land so that the low-temperature seawater can be taken in in order to efficiently cool the condensers 18 </ b> A and 18 </ b> B. It is long and susceptible to marine life. In addition, the LNG vaporizer flow path 27 is in a state in which marine organisms are likely to breed due to the flow of seawater heated by the condensers 18A and 18B, and further heat exchange with the LNG vaporizer 17 In order to improve the efficiency, the diameter of the flow path is smaller than that of the water discharge path 22, so that it is easily affected when marine organisms adhere.

  Therefore, in the present embodiment, by injecting nanobubbles into seawater for heat exchange taken from the water intake 24, the water intake channel 20, the water discharge channel 22, the LNG vaporizer channel 27, and the condenser channel The adhesion of marine organisms such as shellfish on the inner wall surfaces of 29A and 29B is suppressed.

  In addition, by injecting nanobubbles into the seawater for heat exchange heated by the condensers 18A and 18B, adhesion of marine organisms such as shellfish to the inner wall surface of the LNG vaporizer channel 27 is further increased. Suppressed.

  When injecting nanobubbles into seawater taken from the intake port 24, it is preferable to inject nanobubbles at a location near the intake port 24 of the intake channel 20. Thereby, since the swimming of marine organisms can be inhibited upstream of the heat exchange water channel, it is possible to suppress the attachment of marine organisms to the entire heat exchange water channel downstream of the nanobubble injection site.

  Moreover, when injecting nanobubbles into the seawater heated by the condensers 18A and 18B, it is preferable to inject nanobubbles at a location near the entrance of the LNG vaporizer flow path 27. Thereby, the adhesion of marine organisms to the inner wall surface of the LNG vaporizer channel 27 where heat exchange with the LNG vaporizer 17 is performed is suppressed, and the deterioration of the heat exchange function of the LNG vaporizer channel 27 is effectively prevented. .

  FIG. 2 is a diagram schematically showing a heat exchange water channel 50 including the intake channel 20, the discharge channel 22, the LNG vaporizer channel 27, and the condenser channels 29A and 29B.

  As shown in FIG. 2, the intake channel 20 includes first seawater pumps 30 </ b> A and 30 </ b> B at a connection portion with the condensers 18 </ b> A and 18 </ b> B, that is, a connection portion with the condenser flow paths 29 </ b> A and 29 </ b> B, respectively. . The first seawater pumps 30 </ b> A and 30 </ b> B suck the seawater from the sea 2 into the intake channel 20 through the intake port 24.

  The intake channel 20 includes a nanobubble injection device 32 </ b> A preferably at a location close to the intake port 24. Moreover, the LNG vaporizer flow path 27 is equipped with the nano bubble injection apparatus 32B in the location close | similar to an entrance, ie, a connection part with the water discharge path 22, preferably.

FIG. 3 shows a detailed configuration when the nanobubble injection device 32A is a self-contained microbubble generator. The nanobubble injecting device 32A includes a microbubble generating device 40, an injection tube 42 for injecting nanobubbles generated by using the microbubble generating device 40 into seawater for heat exchange flowing through the intake channel 20, and a microbubble. A second seawater pump 44 for supplying seawater to the generator 40 and a CO ₂ cylinder 46 for supplying carbon dioxide to the microbubble generator 40 are provided.

  The second seawater pump 44 takes seawater from the intake channel 20 and supplies the taken seawater to the microbubble generator 40.

  The gas cylinder 46 includes a gas line 47 between the gas cylinder 46 and the microbubble generator 40. The gas line 47 includes a pressure reducing valve 48 and a flow rate adjusting valve 49 in order from the gas cylinder 46 side.

  The gas flowing into the gas line 47 from the gas cylinder 46 is adjusted in pressure so as to become atmospheric pressure by the pressure reducing valve 48, adjusted in flow rate by the flow rate adjusting valve 49, and sent to the microbubble generator 40. This gas is automatically taken into the apparatus when the inside of the apparatus becomes a negative pressure by the force of flowing seawater taken into the microbubble generator 40 by the second seawater pump 44. In this way, nanobubbles are manufactured in the microbubble generator 40 using the gas taken into the microbubble generator 40.

  The injection tube 42 includes an injection port 43 for exhausting the nanobubbles sent from the microbubble generator 40 to the injection tube 42 into seawater for heat exchange flowing through the intake channel 20. The injection tube 42 injects nanobubbles generated by the microbubble generator 40 into seawater for heat exchange flowing through the intake channel 20 through the injection port 43.

  In the example shown in FIG. 3, the tip of the injection pipe 42 on the side not connected to the microbubble generator 40 is bent toward the downstream side of the intake channel 20, and has an injection port 43 at the forefront thereof. In this case, as shown in FIG. 4, the cross section of the tip of the injection tube 42 on the side not connected to the microbubble generator 40 may be configured to gradually expand toward the injection port 43. .

  In addition, as shown in FIG. 5, the tip of the injection tube 42 that is not connected to the microbubble generator 40 may not be bent, and a hole provided on the side surface of the injection tube 42 may be used as the injection port 43. As described above, various configurations of the injection tube 42 and the injection port 43 are conceivable.

  Note that a plurality of injection tubes 42 may be provided at the same place or at a plurality of places.

== Method for suppressing attachment of marine organisms to the heat exchange water flow path according to the present invention ==
Next, as one embodiment of the present invention, a method for suppressing the attachment of marine organisms to the heat exchange water flow path by injecting specific nanobubbles into the water for heat exchange will be described.

  First, using the first seawater pumps 30 </ b> A and 30 </ b> B, seawater containing marine organisms is sucked into the intake channel 20 from the sea 2 through the intake port 24.

  Next, the seawater flowing through the intake channel 20 is supplied to the microbubble generator 40 using the second seawater pump 44. At the same time, an appropriate amount of atmospheric pressure gas is supplied from the gas cylinder 46 to the microbubble generator 40 supplied with seawater through the gas line 47 by passing through the pressure reducing valve 48 and the flow rate adjusting valve 49.

  Within 5 minutes from the start of generating microbubbles, nanobubbles are produced by supplying the seawater flowing through the intake channel 20 to the microbubble generator 40 again using the second seawater pump 44. The specific production method is as described in “Production method of nanobubbles”.

  The seawater containing the nanobubbles thus generated by the microbubble generator 40 is injected into the seawater taken into the intake channel 20 from the inlet 43 through the injection pipe 42. By bringing nanobubbles into contact with marine organisms in this manner, marine organisms can be inhibited from swimming and marine organisms can be prevented from adhering to the heat exchange water channel 50 including the intake channel 20.

  The seawater into which the nanobubbles are injected is supplied through the intake channel 20 to the condenser channels 29A and 29B passing through the condensers 18A and 18B. The seawater supplied to the condenser channels 29A and 29B exchanges heat with the condensers 18A and 18B, respectively, thereby cooling the condensers 18A and 18B.

  The seawater after heat exchange with the condensers 18A and 18B is discharged from the condenser flow paths 29A and 29B to the water discharge path 22. A part of the seawater discharged to the discharge channel 22 is supplied to the LNG vaporizer flow path 27 passing through the inside of the LNG vaporizer.

  Nanobubbles are injected into the seawater supplied to the LNG vaporizer flow path 27 from the nanobubble injector 32B in the same manner as the nanobubble injector 32A. By injecting the nanobubbles into the seawater supplied to the LNG vaporizer flow path 27, the inside of the LNG vaporizer flow path 27 is in a state where marine organisms are easily propagated because it is heated by the condensers 18A and 18B. Can inhibit the swimming of marine organisms and can suppress the attachment of marine organisms to the heat exchange water channel including the LNG vaporizer channel 27 and the discharge channel 22.

  Seawater inside the LNG vaporizer flow path 27 into which the nanobubbles are injected heats the LNG vaporizer 17 by exchanging heat with the LNG vaporizer 17. At this time, since the seawater inside the LNG vaporizer channel 27 is heated by the condensers 18A and 18B, the LNG vaporizer 17 is heated using the heat generated in the condensers 18A and 18B. can do.

  Seawater after heat exchange with the LNG vaporizer 17 is discharged from the LNG vaporizer flow path 27 to the water discharge path 22. Here, among the seawater released from the condenser channels 29A and 29B to the discharge channel 22, the seawater supplied to the LNG vaporizer channel 27 and the seawater not supplied to the LNG vaporizer channel 27 Join.

  The merged seawater is discharged from the water outlet 26 to the sea 2 through the water discharge channel 22. The discharged seawater does not contain any chlorinated chemicals, and since nanobubbles are difficult to dissolve in seawater and are released to the atmosphere, they are very excellent in that they have a low load on the sea 2. .

[Example 1]
Example 1-1
Seawater collected in the Seto Inland Sea (saline concentration: about 3.5% by weight) in a 3L beaker, and CO ₂ microbubbles with a particle size of 50 μm or less are added to seawater using a microbubble generator using a two-phase flow swirl method. Generated inside. The amount of CO ₂ supplied to the microbubble generator was about 50 mL / min. Operate the microbubble generator and stop 3 minutes after starting to generate CO ₂ microbubbles in water. Immediately collect 10 mL of seawater containing CO ₂ microbubbles with a pipette and put it in another beaker. by mixed well and added to the same seawater 40mL seawater was used to generate CO ₂ microbubbles were placed, five-fold diluted with the 4-fold amount of seawater seawater containing CO ₂ microbubbles did. The CO ₂ microbubbles were reduced in water to produce CO ₂ nanobubbles having a particle size of 50 to 5 OOnm.

The number of generated CO ₂ nanobubbles was measured by electron spin resonance (ESR). The measurement principle is described below. Nanobubbles are destabilized and disappeared by adding appropriate amounts of spin trapping agent and hydrochloric acid. At the time of extinction, energy stored as a charge amount at the gas-liquid interface diverges, and free radicals (hydroxyl radicals) are generated by decomposing gas molecules existing inside and around the nanobubbles. The amount of free radicals is characterized by reflecting the number of nanobubbles almost linearly if basic conditions such as water quality are in place. Therefore, the number of nanobubbles can be calculated by measuring the amount of generated free radicals. In this example, DMPO (5,5-Dimethyl-1-pyrroline N-oxide) was used as a spin trap agent. FIG. 6 shows the obtained ESR spectrum.

As apparent from FIG. 6, a characteristic DMPO-OH signal of 1: 2: 2: 1 could be confirmed in the left and right Mn indices. When the number of CO ₂ nanobubbles generated in seawater containing CO ₂ microbubbles not diluted with seawater was measured in the same manner, the peak height of the DMPO-OH signal included CO ₂ microbubbles. It was 1/3 or less of the sample which diluted seawater 5 times. From this, it was found that the number of CO ₂ nanobubbles generated in water could be increased by 3 times or more by diluting seawater containing CO ₂ microbubbles 5 times.

Example 1-2:
A commercially available artificial seawater (salt concentration: about 3.5% by weight, Aquamarine S manufactured by Yasu Pharmaceutical Co., Ltd.) was placed in a 30 L container, and artificial seawater was prepared using deionized water. CO ₂ microbubbles having a particle size of 50 μm or less were generated in seawater using a microbubble generator using a two-phase flow swirling method. The amount of CO ₂ supplied to the microbubble generator was about 1 L / min. The CO ₂ microbubbles were reduced in water to produce CO ₂ nanobubbles having a particle size of 50 to 500 nm. Use by actuating the micro-bubble generating device of CO ₂ microbubbles when 2 minutes from the start is generated has elapsed in water, artificial seawater was collected containing CO ₂ microbubbles, in order to immediately generate CO ₂ microbubbles The same artificial seawater as that used to be diluted was diluted 5-fold. The number of CO ₂ nanobubbles generated in the sample water was measured in the same manner as in Example 1-1. The ESR spectrum of this sample is shown in FIG.

In addition, when 1 minute has passed since the start of generation of CO ₂ microbubbles in water, the artificial seawater containing CO ₂ microbubbles was collected, and the number of CO ₂ nanobubbles generated in the water of the sample left for 2 minutes was determined. Measurement was performed in the same manner as in Example 1-1. The ESR vector of this sample is shown in FIG.

As apparent from FIGS. 7 and 8, the sample in which artificial seawater containing CO ₂ microbubbles was allowed to stand for 2 minutes without dilution with artificial seawater has a small number of CO ₂ nanobubbles generated in water, and DMPO The peak of the -OH signal was very small. On the other hand, a sample obtained by diluting artificial seawater containing CO ₂ microbubbles with artificial seawater had a very large number of CO ₂ nanobubbles generated in the water, and the DMPO-OH signal peak was very large.

The are brought to CO ₂ microbubbles actuating the microbubble generating apparatus from the start is generated in the water, when the 1 minute or 3 minutes has elapsed, the artificial seawater containing CO ₂ microbubbles collected immediately including CO ₂ microbubbles The number of CO ₂ nanobubbles generated in the sample water diluted five times using the same sea water as that used to generate CO ₂ microbubbles was measured in the same manner as in Example 1-1. Example 1-3 in which the number of CO ₂ nanobubbles generated in water was large and the DMPO-OH signal peak was large, similar to the sample diluted immediately after stopping the apparatus in 2 minutes:
The experiment was conducted in the same manner as in Example 1-1 except that the apparatus was stopped after 3 minutes from the start of generating CO ₂ microbubbles in water and left for 2 minutes and then diluted 5 times. The number of produced CO ₂ nanobubbles was large, and the DMPO-OH signal peak was large.

Example 1-4:
The experiment was conducted in the same manner as in Example 1-1, except that the apparatus was stopped when 5 minutes had elapsed since the start of generation of CO ₂ microbubbles in water, and immediately diluted 2-fold. The number of CO ₂ nanobubbles was large, and the DMPO-OH signal peak was large.

Example 1-5:
An experiment similar to Example 1-1 was performed except that oxygen was supplied to the microbubble generator, and the same result as in Example 1 was obtained.

Example 1-6:
An experiment similar to Example 1-1 was performed except that a 1.0 wt% aqueous sodium chloride solution was used instead of seawater, and the same result as in Example 1 was obtained.

[Example 2]
Example 2-1
The apparatus is stopped when about 5 minutes have passed since the start of generation of CO ₂ microbubbles in water, and the same procedure as in Example 1-1 was performed except that the apparatus was immediately diluted 1.5, 2, 3, 5, and 10 times. Seawater containing nanobubbles. As controls, seawater containing undiluted microbubbles (shown as “stock solution” in FIG. 9) and seawater used to generate CO ₂ microbubbles (shown as “cont” in FIG. 9) were used. .

After diluting the seawater containing CO ₂ microbubbles, let it stand for about 1 minute, and inject 14-29 individuals of the red larvae Noprius late larvae into seawater (24 ° C) containing 10 mL of nanobubbles, 3, 5, 10 minutes Later, the paralyzed individuals were counted. The result is shown in FIG.

  Compared to the stock solution, the paralysis rate increased even when diluted 1.5 times, and the effect continued for at least 5 minutes. With 5-fold and 10-fold diluted seawater, the paralysis rate increased significantly and the effect lasted until at least 10 minutes.

  Thus, by bringing the nanobubbles produced according to the present invention into contact with the attached organism larvae, the attached organism larvae can be efficiently and paralyzed for a long time.

Example 2-2:
The seawater containing nanobubbles was prepared in the same manner as in Example 1-1 except that the apparatus was stopped when about 5 minutes had passed since the CO ₂ microbubbles were generated in the water, and immediately after dilution by 10, 20 times. . As a control, seawater (indicated as “cont” in FIG. 9) used for generating CO ₂ microbubbles was used.

After dilution of seawater containing CO ₂ microbubbles, the mixture was allowed to stand for about 3,15,30 minutes, and 12-29 individuals of red larvae noprius late larvae were introduced into seawater (24 ° C.) containing 10 mL of nanobubbles, After 5 to 10 minutes, paralyzed individuals were counted. The result is shown in FIG.

  From the results of Example 2-1, in the seawater containing undiluted microbubbles, the paralysis rate is about 25%. In this example, the seawater production containing nanobubbles was performed in both 10-fold and 20-fold dilutions. Even after 30 minutes of standing, the effect of paralysis on the late larvae of the red barnacle Nauplius was observed.

  Thus, the nanobubble produced by this invention shows the paralysis effect with respect to an attached organism larva even 30 minutes after production.

2 Sea 10 Thermal power plant 12 Fuel storage facility 14 LNG tank 16 Power generation facility 17 LNG vaporizer 18A, 18B Condenser 20 Intake channel 22 Discharge channel 24 Intake port 26 Discharge port 27 LNG vaporizer channel 29A, 29B Condenser Flow path 30A, 30B First seawater pump 32A, 32B Nanobubble injection device 40 Nanobubble generator 42 Injection pipe 43 Inlet 44 Second seawater pump 46 Gas cylinder 47 Gas line 48 Pressure reducing valve 49 Flow control valve 50 Heat exchange water flow path

Claims (9)

A method for inhibiting the swimming of marine organisms, comprising the step of contacting nanobubbles with said marine organisms,
The nanobubbles are produced by adding second water having a salt concentration of 0.5% by weight or more within 5 minutes from the start of generating microbubbles in the first water having a salt concentration of 0.5% by weight or more. Was the way.   The method of claim 1, wherein the water is produced by adding a second water within 3 minutes of starting to generate microbubbles in the first water.   The method according to claim 1 or 2, wherein the water is diluted 1.5 times or more by adding the first water to the second water.   The method according to any one of claims 1 to 3, wherein the first water and / or the second water is seawater.   The method of any one of Claims 1-4 whose gas for generating a microbubble is a carbon dioxide.   The suppression method according to claim 1, wherein the marine organisms are barnacle larvae.   The suppression method of any one of Claims 1-6 whose particle size of the said nano bubble is 1-999 nm. A system for suppressing the attachment of marine organisms to the heat exchange water flow path,
A supply device for supplying water containing the marine organisms to heat exchange target equipment;
A heat exchanger for exchanging heat with the heat exchange target facility using the supplied heat exchange water;
A discharge device for discharging the heat exchange target equipment and water after heat exchange from the heat exchange target equipment;
An injection device for injecting water containing nanobubbles into any one or more of the water containing the marine organisms, the supplied water, and the heat exchange target equipment and the water after heat exchange;
The water containing the nanobubbles is added with the second water having a salt concentration of 0.5% by weight or less within 5 minutes from the start of generating microbubbles in the first water having a salt concentration of 0.5% by weight or more. Manufactured by the system. A method for suppressing the attachment of marine organisms to a heat exchange water flow path,
Supplying water containing marine organisms to the facility subject to heat exchange;
Using the supplied water to exchange heat with the heat exchange target equipment;
Discharging the heat exchange target equipment and water after heat exchange from the heat exchange target equipment;
Injecting water containing nanobubbles into any one or more of the water containing the marine organisms, the supplied water, and the heat exchange target equipment and the water after the heat exchange,
The water containing the nanobubbles is added with the second water having a salt concentration of 0.5% by weight or less within 5 minutes from the start of generating microbubbles in the first water having a salt concentration of 0.5% by weight or more. The suppression method manufactured by this.