Seaweed net acid treatment ship
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DAIICHI CO LTD
- Filing Date
- 2025-01-10
- Publication Date
- 2026-07-23
Smart Images
Figure 2026121085000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an acid treatment ship for seaweed nets that acid-treats fungi such as diatoms and red rot bacteria adhering to seaweed nets during cultivation with an acid treatment agent (liquid), and particularly to a box-shaped ship (double-type box-shaped ship with a sheet member) having a pair of winding rolls, a pair of rewinding rolls, and a support member hanging sheet-like member in an acid treatment tank.
Background Art
[0002] Conventionally, in seaweed farms, acid treatment ships for seaweed nets that effectively perform acid treatment on fungi such as diatoms and red rot bacteria adhering to seaweed nets extended on the sea surface with an acid treatment agent having a composition combination of organic acids such as citric acid and malic acid are known in many types and structures.
[0003] Such an acid treatment ship for seaweed nets generally immerses the seaweed net in an acid treatment liquid with a certain pH value to accelerate the growth of seaweed and, moreover, harvest high-quality seaweed by keeping the growth of each seaweed net in a constant state. This acid treatment ship for seaweed nets is composed of an acid treatment tank with a certain capacity, a seaweed net hoisting device, an acid stock solution replenishing device for replenishing the acid stock solution into the acid treatment tank, and a control unit that detects the pH value of the acid treatment liquid in the acid treatment tank and operates the replenishing device based on the detected value to maintain the acid treatment liquid at a certain pH value, for example, around pH 2.0 (see, for example, Patent Document 1).
[0004] Also, as an acid treatment ship for small seaweed nets, an acid treatment ship using a box-shaped ship is known. As this acid treatment ship for small seaweed nets, for example, 1) An acid treatment ship for seaweed nets having an acid treatment tank provided with a seaweed net hoisting device for hoisting the seaweed net from the sea, a chemical solution circulation device for circulating the chemical solution, and a concentration detection device for detecting the concentration of the chemical solution circulated by the chemical solution circulation device (see, for example, Patent Document 2). 2) A box-shaped vessel capable of maintaining an acid treatment solution at a desired pH value, comprising an acid treatment tank for storing the acid treatment solution, and a pair of winding rolls provided in the acid treatment tank for winding up seaweed nets to which seaweed is attached, wherein the box-shaped vessel comprises a pH sensor provided in the acid treatment tank for detecting the pH of the acid treatment solution, a concentrate discharge unit provided in a position that does not interfere with the seaweed nets wound up on the winding rolls for discharging concentrate acid solution, and a concentrate supply device that automatically adjusts the amount of concentrate acid solution supplied to the concentrate discharge unit based on the pH sensor's detection value, wherein the concentrate discharge unit comprises a rod-shaped member provided between the pair of winding rolls and positioned above the acid treatment tank so as to face the surface of the acid treatment solution, a sheet member hanging down from the rod-shaped member toward the surface of the acid treatment solution, and tubular members provided on both sides of the sheet member along the rod-shaped member and having a plurality of discharge holes formed at predetermined intervals for discharging concentrate acid solution toward the sheet member (see, for example, Patent Document 3). 3) In order to prevent the acid concentrate or an acid treatment solution with a higher concentration than desired from coming into contact with the seaweed nets during acid treatment of seaweed nets, a box-shaped vessel is provided, comprising an acid treatment tank for storing an acid treatment solution diluted from the acid concentrate, and a winding roll provided in the acid treatment tank for winding up seaweed nets to which seaweed has been attached, wherein the vessel is provided with a flexible sheet that hangs down and is separated from the winding roll, and an acid concentrate discharge section for discharging the acid concentrate onto the surface of the flexible sheet, and an acid concentrate supply section for supplying the acid concentrate to the acid treatment tank by allowing it to flow down the surface of the flexible sheet, wherein the acid concentrate supply section is provided when the acid treatment tank is tilted so that the lower end of the flexible sheet approaches the winding roll. , a box-shaped vessel characterized in that the acid concentrate is supplied to a position further from the winding roll than the lower end of the flexible sheet at the liquid surface of the acid treatment solution, and the flexible sheet has an opening or notch at its upper end located above the liquid surface of the acid treatment solution, and the acid concentrate discharge section is configured to discharge the acid concentrate so that the acid concentrate flows into the upper end of the opening or notch, and the opening is configured to be formed in multiple stages in the vertical direction, and further, the flexible sheet has a notch at its upper end located above the liquid surface of the acid treatment solution, and a rib hanging down from the upper end of the notch, etc. (see, for example, Patent Document 4), 4) A box-shaped vessel is known that, in order to suppress or prevent the acid concentrate from adhering to the seaweed net, comprises an acid treatment tank for storing the acid treatment liquid and a winding roll provided in the acid treatment tank for winding up the seaweed net to which the seaweed has been attached, wherein the acid treatment tank is provided with a pH sensor for detecting the pH of the acid treatment liquid, a concentrate discharge unit for discharging the acid concentrate into the acid treatment liquid in the acid treatment tank, and a concentrate supply device for automatically adjusting the amount of the acid concentrate supplied to the concentrate discharge unit based on the value detected by the pH sensor, wherein the concentrate discharge unit is provided at the bottom of the sheet member or hanging down from above via the sheet member (see, for example, Patent Document 5 or Patent Document 6).
[0005] Patent documents 3 to 6 describe a box-shaped vessel (a so-called double-type box-shaped vessel with a sheet-like member) having a pair of winding rolls, a pair of straightening rolls, and a supporting sheet-like member. This box-shaped vessel winds seaweed nets from the cultivation area into an acid treatment tank using one winding roll, and then in the next step, similarly winds another seaweed net from the cultivation area onto the other winding roll, so that two seaweed nets are immersed in the acid treatment solution in the acid treatment tank at the same time using a pair of winding rolls. During this series of acid treatment operations, in order to ensure that the immersion time at the beginning and end of winding is equal, a process is carried out in which the seaweed nets wound on the winding rolls are rewound onto the straightening rolls facing each other in the acid treatment tank. As mentioned above, the double-type box-shaped vessel with a sheet-like member is widely used as an acid treatment vessel for seaweed cultivation because it offers excellent work efficiency and enables proper acid treatment work to be achieved with equal time.
[0006] In a double-type box-shaped vessel with a sheet member, the primary role of the sheet member is to act as a spacer to prevent the problem of the seaweed nets wound on one winding roll coming into direct contact with the other winding roll's seaweed net, causing the net threads to entangle and hindering the acid treatment process. When the seaweed nets with grown cultivated seaweed attached are transferred from the winding roll to the winding roll, the radius of the seaweed net roll (the seaweed nets wound on the winding roll) exceeds the horizontal distance between the winding roll and the sheet member. As a result, the sheet member is pushed by the seaweed net roll, which has become excessively large in diameter. However, because the sheet member is flexible and moves with flexibility, it moves in a way that allows it to curve without resistance in the direction of the pressure from the seaweed net roll. Furthermore, when a rewinding roll is pressed against a seaweed net roll with such an excessive diameter, the seaweed net of the other rewinding roll is in the process of being rewound into the sea, so the diameter of that seaweed net roll decreases, and the load on both rolls remains within an acceptable range. Thus, sheet-like members utilize the flexible properties of materials such as soft polyvinyl chloride to prevent entanglement of seaweed nets. However, in box-shaped vessels using partitions made of non-flexible materials such as FRP (for example, as described in Japanese Patent Publication No. 8-298885), this effect does not work, requiring the horizontal distance between the winding roll and the sheet-like member to be greater than the diameter of the seaweed net roll. Consequently, these vessels are longer in the direction of travel than those using sheet-like members, which can make them difficult to maneuver in pole-supported aquaculture fishing grounds such as those in the Ariake Sea area of Saga and Fukuoka prefectures.
[0007] In the aforementioned Patent Documents 3 and 4, where the acid concentrate is supplied flowing down the surface of a sheet-like member, the acid concentrate adheres to and remains on the sheet member. In this case, if the amount of seaweed net being wound up by the winding roll increases, the outer edge of the wound-up seaweed net may come into contact with the sheet member, causing the acid concentrate to come into contact with the seaweed on the net and potentially damaging the seaweed during cultivation. Furthermore, since the acid concentrate supplied to the surface of the sheet member is located on the upper side of the acid treatment tank, if the discharge speed is high or if there are strong winds in the sea area, the risk of the acid concentrate spraying onto the seaweed net increases, posing further problems.
[0008] Furthermore, while Patent Documents 5 and 6 discharge the acid concentrate into the acid treatment liquid of the acid treatment tank, thus eliminating the possibility of direct contact between the acid concentrate and the seaweed nets above the liquid surface, as in Patent Documents 3 and 4, and the risk of splash contact, the tubular member or other concentrate discharge part is provided in a state where it hangs down from the bottom of the sheet-like member or through the sheet-like member, which impairs the flexible properties of the sheet-like member and hinders its intended function of preventing seaweed nets from entangling. [Prior art documents] [Patent Documents]
[0009] [Patent Document 1] Japanese Patent Publication No. 5-95740 (Claims, Figure 1, etc.) [Patent Document 2] Utility Model Registration No. 3212304 (Claims for Utility Model Registration, Figure 1, etc.) [Patent Document 3] Japanese Patent Publication No. 6161016 (Claims, Figures 1, 2, etc.) [Patent Document 4] Japanese Patent Publication No. 6218984 (Claims, Figures 1-4, etc.) [Patent Document 5] Japanese Patent Publication No. 6898087 (Claims, Figures 1-4, etc.) [Patent Document 6] Japanese Patent Publication No. 7160399 (Claims, Figures 1-4, etc.) [Overview of the Initiative] [Problems that the invention aims to solve]
[0010] The present invention aims to solve the aforementioned problems of the conventional methods, and provides a seaweed net acid treatment vessel that uses an acid treatment agent (liquid) to acid-treat seaweed nets to remove diatoms and fungi such as red rot bacteria that adhere to seaweed nets during cultivation. In this vessel, the wound-up seaweed nets do not come into contact with the acid concentrate remaining on the sheet-like member, nor do they become droplets and diffuse into the air. Since the tubular member of the present invention is not attached to the sheet-like member, it does not impair the flexible properties of the sheet-like member, and does not interfere with the original function of the sheet-like member in preventing seaweed nets from entangling on both sides. The acid concentrate can be efficiently supplied to the acid treatment solution, and the opportunity for concentrated acid concentrate to come into contact with the seaweed nets in the acid treatment solution is suppressed, thereby providing a seaweed net acid treatment vessel that can reliably acid-treat seaweed nets with the acid treatment solution. [Means for solving the problem]
[0011] As a result of diligent study on the aforementioned conventional problems, the inventors have found that, in a seaweed net acid treatment vessel comprising at least an acid treatment tank for containing an acid treatment solution, a pair of winding rolls for winding seaweed nets provided in the acid treatment tank, a pair of rewinding rolls for rewinding the seaweed nets wound on the winding rolls in the acid treatment tank, a support member suspended in the center of the acid treatment tank, a sheet-like member hanging from the support member into the acid treatment solution in the acid treatment tank, an acid concentrate supply device for supplying the concentrate of the acid treatment solution into the acid treatment tank, and a control unit that detects the pH value of the acid treatment solution in the acid treatment tank and operates the acid concentrate supply device based on the detected value to control the acid treatment solution to a constant pH value, the inventors have found that, by providing a tubular member with a specific structure, etc., in the acid concentrate supply device at a specific position and under specific conditions in the acid treatment tank, the aforementioned seaweed net acid treatment vessel can be obtained, and thus the inventors have completed the present invention.
[0012] In other words, they are found in (1) to (4) below. (1) A seaweed net acid treatment vessel comprising at least an acid treatment tank for containing an acid treatment solution, a pair of winding rolls provided in the acid treatment tank for winding up seaweed nets from a cultivation area, a pair of rewinding rolls for rewinding the seaweed nets wound on the winding rolls in the acid treatment tank, a support member suspended in the center of the acid treatment tank, a sheet-like member hanging from the support member into the acid treatment solution in the acid treatment tank, an acid concentrate supply device for supplying concentrate of the acid treatment solution into the acid treatment solution in the acid treatment tank, and a control unit for detecting the pH value of the acid treatment solution in the acid treatment tank and operating the acid concentrate supply device based on the detected value to control the acid treatment solution to a constant pH value, wherein the acid concentrate supply device has a tubular member provided parallel to the sheet-like member on the bottom surface of the acid treatment tank near both sides of the sheet-like member and having a plurality of discharge holes for discharging concentrate of the acid. (2) The seaweed net acid treatment vessel according to (1) above, characterized in that the direction of discharge of the undiluted acid from the discharge hole of the tubular member is horizontal or inclined downward with respect to the bottom surface of the acid treatment tank. (3) The seaweed net acid treatment vessel according to (1) or (2) above, characterized in that the tubular member is located between a pair of winding rolls. (4) The seaweed net acid treatment vessel according to (1) or (2) above, characterized in that the tubular member is located between a pair of winding rolls. In this invention, "discharge" refers to the supply of concentrated acid solution to the acid treatment solution through a discharge port at a constant pressure. [Effects of the Invention]
[0013] According to the invention of claim 1, the acid concentrate supply device has a tubular member provided parallel to the sheet-like member on both sides of the sheet-like member at the bottom surface of the acid treatment tank, and equipped with a plurality of discharge holes for discharging the acid concentrate. Therefore, there is no risk of damage to the seaweed net from direct contact with the acid concentrate above the acid treatment liquid surface or from airborne splashes. The acid concentrate is discharged evenly in the lateral direction (width direction) so as to smoothly ride the flow of the acid treatment liquid in the direction of the ship's movement (forward and backward) on the bottom surface of the box-shaped ship, and the seaweed net can be reliably acid-treated with an acid treatment liquid with uniform pH control without interfering with the seaweed net entanglement prevention effect of the sheet-like member. According to the invention of claim 2, since the direction of the discharge of the concentrated acid solution from the discharge holes of the tubular member is horizontal or inclined downward from the horizontal with respect to the bottom surface of the acid treatment tank, the discharge of the concentrated acid solution can be made to match the flow of the acid treatment liquid in the acid treatment tank in the direction of the box-shaped ship's progress, and a laver net acid treatment ship that can more appropriately perform acid treatment on the laver net with an acid treatment liquid having uniform pH control that suppresses the opportunity of contact between the laver net and the concentrated acid solution is provided. According to the invention of claim 3 or 4, since the tubular member is between a pair of winding rolls or between a pair of rewinding rolls, dilution and diffusion of the concentrated acid solution after discharge from an appropriate position are achieved, and a laver net acid treatment ship that can more appropriately perform acid treatment on the laver net with an acid treatment liquid having uniform pH control that suppresses the opportunity of contact between the laver net and the concentrated acid solution is provided.
Brief Description of the Drawings
[0014] [Figure 1] It is a drawing of a laver net acid treatment ship showing an example of an embodiment of the present invention, where (a) is a schematic plan view, (b) is a schematic front view, and (c) is a schematic side view. [Figure 2] It is a front drawing showing an example of a tubular member used in the laver net acid treatment ship of FIG. 1, where (a) is a schematic view seen from the central side of the acid treatment ship, and (b) is a schematic view seen from the opposite side.
Embodiments for Carrying Out the Invention
[0015] Hereinafter, each embodiment of the present invention will be described in detail. FIG. 1 is a drawing of a laver net acid treatment ship showing an example of an embodiment of the present invention, where (a) is a schematic plan view, (b) is a schematic front view, and (c) is a schematic side view. FIG. 2 is a front drawing showing an example of a tubular member used in the laver net acid treatment ship of FIG. 1, where (a) is a schematic view seen from the central side of the acid treatment ship, and (b) is a schematic view seen from the opposite side. An example of the acid treatment ship A for laver nets according to an embodiment of the present invention, as shown in FIGS. 1(a), (b), and (c), includes, at least, an acid treatment tank 15 for storing an acid treatment liquid 11, a winding roll 20 for winding a laver net (not shown) provided in the acid treatment tank 15, a pair of rewinding rolls 21 for rewinding the laver net (not shown) wound around the winding roll 20 in the acid treatment tank, a support member 25 suspended at the central portion of the acid treatment tank 15, a sheet-like member 30 hanging from the support member 25 toward the acid treatment liquid 11 in the acid treatment tank 15, an acid stock solution supply device 40 for supplying an acid stock solution Z of the acid treatment liquid 11 into the acid treatment tank 15, and a control unit 50 for detecting the pH value of the acid treatment liquid 11 in the acid treatment tank 15 and operating the acid stock solution supply device 40 based on the detected value to control the acid treatment liquid 11 to a constant pH value.
[0016] The acid treatment liquid 11 is a dilution of an acid stock solution [if there is a commercially available product, a commercially available acid treatment agent (liquid), in this embodiment, "Grogen" manufactured by Daiichi Co., Ltd.] Z such as an organic acid like citric acid and malic acid with seawater or the like, and is an acid dilution liquid having a predetermined pH value, for example, pH 1.7 to 2.3. A certain amount (500 to 1,000 L) of this acid treatment liquid 11 is stored in the acid treatment tank 15, and the laver adhering to the laver net is acid-treated by immersing the laver net (not shown) to be wound.
[0017] The acid treatment tank 15 is a rectangular concave body formed at the center of the ship body 10 and stores a predetermined amount of the acid treatment liquid 11. In the spaces 16, 16 on both sides of the acid treatment tank 15, an acid stock solution supply device 40, a control unit 50, a drive unit (not shown) such as a winding roll, a battery (not shown) for driving these, etc. are arranged, and it also serves as a working space for an operator.
[0018] The winding rolls 20 are the rotating shafts for winding the seaweed nets and are arranged in pairs at predetermined locations within the acid treatment tank 15. These winding rolls 20, 20 are rotatably mounted, with one winding roll 20 sequentially winding the seaweed nets in front when the ship hull 10 moves forward (upper side in Figure 1), and the other winding roll 20 sequentially winding the seaweed nets in rear when the ship hull 10 moves backward (lower side in Figure 1). In addition, a pair of rewinding rolls 21, 21, which serve as rotating shafts for rewinding the seaweed nets wound on the winding rolls 20, 20 within the acid treatment tank, are rotatably mounted near both sides of the support member 25. The rewinding rolls 21, 21 also function as payout rolls, which feed out the rewound seaweed nets towards the aquaculture area. The pair of winding rolls 20, 20 and the pair of straight winding rolls 21, 21, which are located on both sides of the support member 25, are driven by a drive unit (not shown) having an operating device provided in the space 16.
[0019] The support member 25 is composed of a rod-shaped member and is suspended in the center of the acid treatment tank 15 in the width direction, and is fixed to the upper surfaces on both sides of the acid treatment tank 15 either via mounting members or directly. A sheet-like resin member 30, in this embodiment a sheet-like resin member 30 made of soft polyvinyl chloride, is attached to this support member 25, which hangs down toward the acid treatment liquid 11 of the acid treatment tank 15. In this embodiment, it is positioned near the bottom of the acid treatment liquid 11 in the acid treatment tank 15. A rod-shaped member 31, which acts as a weight (sinker), is attached to the bottom of the sheet-like member 30. This sheet-like member 30 acts as a curtain to prevent the seaweed nets wound onto the pair of winding rolls 21, 21 positioned on both sides of the sheet-like member 30 from becoming entangled. Therefore, it is preferable that the lower part of the sheet-like member 30 extends to near the bottom of the acid treatment liquid 11 in the acid treatment tank 15.
[0020] As shown in Figure 1(a), the acid concentrate supply device 40 is positioned at an appropriate location in the space 16 of the acid treatment tank 15 (away from the acid treatment tank to the extent that it does not interfere with the winding and unwinding of the seaweed nets, and does not get in the way of work, for example, in the space under the worker's simple seat), and supplies the acid concentrate Z of the acid treatment liquid 11 into the acid treatment tank 15. In this embodiment, the acid concentrate supply device 40 includes a concentrate tank 41 that contains the acid concentrate Z of the acid treatment liquid 11, a line 43 that connects the concentrate tank 41 to a pump 42, and a line 44 that connects the pump 42 to a tubular member 60. The control unit 50 has a pH detector 51 located at an appropriate position within the acid treatment tank 15 (a central position where the average pH of the acid treatment tank can be detected, and which is not interfered with by the winding roll, for example, near the sheet-like member) to detect the pH value of the acid treatment solution 11. Based on the detected value from the pH detector 51, the control unit 50 operates the pump 42 of the acid stock solution supply device 40 to supply the acid stock solution Z into the acid treatment tank 15 and controls the acid treatment solution to a constant pH value. The control unit 50 automatically adjusts the amount of acid stock solution Z supplied based on the detected value from the pH detector 51.
[0021] On the bottom surface of the acid treatment tank 15, resin tubular members 60, 60 are attached parallel to the sheet-like member 30 near both sides of the sheet-like member 30, and in this embodiment, FRP tubular members 60, 60 with a length of 190 cm, an inner diameter of 3 mm, and an outer diameter of 8 mm are attached by adhesive or the like. As shown in Figures 1 and 2, the tubular member 60 is supplied with concentrated acid solution Z from one opening, and a stopper member 62 is fixed to the other end. The tubular member 60 in this embodiment is provided with a plurality of discharge holes 61a, 61b... on its longitudinal side (horizontal to the bottom surface of the acid treatment tank 15 and in the direction of travel) for discharging the concentrated acid solution Z into the acid treatment liquid 11 in the acid treatment tank 15. The discharge holes 61a, 61b... can be provided in a predetermined number at predetermined intervals, but in this embodiment, as shown in Figure 2, six discharge holes (61a to 61f) are provided at equal intervals, taking into consideration the pressure (water pressure) of the pump 42 supplying the concentrated acid solution Z and the length of the tubular member, in order to discharge an equivalent amount of concentrated acid solution from each discharge hole 61a, 61b...
[0022] The acid treatment of seaweed nets using the seaweed net acid treatment vessel of this embodiment, configured as described above, will be explained below. Since the process is the same whether the vessel 10 is moving forward or backward, this embodiment will only describe the case where the vessel 10 is moving forward (upper side of Figure 1). After moving the seaweed net acid treatment vessel A to the sea where the cultivated seaweed nets are installed, the vessel 10 is moved forward. As it moves forward, the seaweed nets enter the acid treatment tank 15 from the front, and the entered seaweed nets are sequentially wound onto the winding rolls 20 as the winding rolls 20 are rotated by the drive unit (not shown). The wound seaweed nets are then immersed in the acid treatment liquid 11 contained in the acid treatment tank 15, and the seaweed is acid-treated. Inside the acid treatment tank 15, the pH of the acid treatment solution 11 is detected by a pH detector 51, and the detected value from the pH detector 51 is output to the control unit 50. Based on the detected value input from the pH detector 51 and a preset control threshold, the control unit 50 provides feedback control to the pump 42 of the acid concentrate supply device 40. Based on the operation signal input from the control unit 50, the pump 42 draws a predetermined amount of acid concentrate Z corresponding to the operation signal from the acid concentrate tank 41 and supplies it to the tubular members 60, 60 via the line 44. Furthermore, the control unit 50 can automatically adjust the amount of acid concentrate Z supplied to the acid treatment solution 11 by controlling the pump 42 based on the detected value from the pH detector 51.
[0023] The acid concentrate Z, drawn from the acid concentrate tank 41 by the pump 42 upon receiving an operating signal from the pH detector 51, is supplied to the tubular members 60, 60, and is discharged into the acid treatment liquid 11 through a plurality of discharge holes 61a to 61f (each) provided in the tubular members 60, 60. The acid concentrate Z discharged into the acid treatment liquid 11 from the tubular members 60 (discharge holes 61a to 61f) in this embodiment smoothly merges with the acid treatment liquid flow in the direction of ship movement (forward and backward longitudinal direction) at the bottom of the acid treatment tank 15, and immediately diffuses and dissolves in the acid treatment liquid 11. This solubility is due to the fact that the acid stock solution Z is water-soluble, and upon merging, the acid treatment solution 11 is agitated by the swirling of the ship's hull 10, the rotation of the winding roll 20, etc., causing the acid treatment solution 11 to dissolve and diffuse into the acid treatment solution 11, which has been diluted with seawater during the acid treatment. This allows the pH value in the acid treatment solution 11, which has fluctuated to a high value, to be brought down to a predetermined pH value. The pH value can also be checked on a waterproof pH display LCD screen (not shown) provided in the control unit 50. The seaweed nets to which the cultivated seaweed to be treated with acid are wound onto the winding roll 20 and then rewound onto the rewinding roll 21. After being treated with acid, the seaweed nets wound onto the rewinding roll 21 are unwound out of the ship 10 as the ship moves forward and are installed in the seaweed cultivation area where the seaweed nets were originally installed.
[0024] According to the acid treatment vessel A for seaweed nets of this embodiment, configured as described above, the acid concentrate supply device 40 has tubular members 60, 60 provided parallel to the sheet-like member 30 on the bottom surface of the acid treatment tank 15 near both sides of the sheet-like member 30, and equipped with a plurality of discharge holes 61a, 61b... that discharge the acid concentrate Z into the acid treatment liquid 11 on its longitudinal side (horizontal to the bottom surface of the acid treatment tank 15 and in the direction of travel). As a result, the wound-up seaweed nets do not come into contact with the acid concentrate remaining on the sheet-like member, nor do they become droplets and diffuse into the air. This allows for efficient supply of the acid concentrate to the acid treatment liquid without interfering with the original function of the sheet-like member in preventing the seaweed nets from entangling on both sides, and also reduces the opportunity for concentrated acid concentrate to come into contact with the seaweed nets in the acid treatment liquid, thereby providing an acid treatment vessel for seaweed nets that can reliably acid-treat the seaweed nets with the acid treatment liquid.
[0025] The present invention is not limited to the above-described example of an embodiment, and the following modified embodiments can be adopted without altering the essence of the invention. In this invention, tubular members 60, 60 equipped with multiple discharge holes 61 (61a, 61b...) for discharging the acid stock solution Z into the acid treatment solution are provided on the bottom surface of the acid treatment tank 15, near both sides of the sheet-like member 30 and parallel to the sheet-like member 30.Tubular members 60, 60 with an inner diameter of 3 to 13 mm and equipped with 3 to 10 discharge holes with a hole diameter of 1.0 to 2.0 mm are preferably installed between the winding rolls so that the acid stock solution is discharged from the discharge holes in a direction horizontal or inclined below horizontal relative to the bottom surface in the direction of the ship's movement (forward and backward longitudinal directions), allowing for smooth integration with the acid treatment solution flow and immediate diffusion and dissolution in the acid treatment solution 11, thus properly obtaining the effects of this invention.However, other applications are also possible. For example, the tubular members 60, 60 may be provided between the winding rolls, and the undiluted acid may be discharged from the discharge hole in a direction that is inclined upward from the horizontal with respect to the bottom surface. [Industrial applicability]
[0026] This can be effectively used in seaweed net acid treatment vessels, which can efficiently treat diatoms and fungi such as red rot bacteria that attach to seaweed nets during cultivation with an acid treatment agent (liquid). [Explanation of Symbols]
[0027] A seaweed net acid treatment vessel Y Acid treatment liquid level Z acid stock solution 10. Ship hull 11 Acid treatment solution 15 Acid treatment tank 20 reel rolls 21 straight roll 25 Support member 30 Sheet-like member 40 Acid stock solution supply equipment 50 Control Unit 51 pH detector (pH sensor) 60 Tubular member 61. Extrusion port
Claims
1. An acid treatment vessel for seaweed nets, comprising at least an acid treatment tank for containing an acid treatment solution, a pair of winding rolls provided in the acid treatment tank for winding up seaweed nets from a cultivation area, a pair of rewinding rolls for rewinding the seaweed nets wound on the winding rolls in the acid treatment tank, a support member suspended in the center of the acid treatment tank, a sheet-like member hanging from the support member into the acid treatment solution in the acid treatment tank, an acid concentrate supply device for supplying concentrate of the acid treatment solution into the acid treatment solution in the acid treatment tank, and a control unit for detecting the pH value of the acid treatment solution in the acid treatment tank and operating the acid concentrate supply device based on the detected value to control the acid treatment solution to a constant pH value, wherein the acid concentrate supply device has a tubular member provided parallel to the sheet-like member near both sides of the sheet-like member on the bottom surface of the acid treatment tank and having a plurality of discharge holes for discharging concentrate of the acid.
2. The seaweed net acid treatment vessel according to claim 1, characterized in that the direction of discharge of the undiluted acid solution from the discharge hole of the tubular member is horizontal or inclined downward with respect to the bottom surface of the acid treatment tank.
3. The seaweed net acid treatment vessel according to claim 1 or 2, characterized in that the tubular member is located between a pair of winding rolls.
4. The seaweed net acid treatment vessel according to claim 1 or 2, characterized in that the tubular member is located between a pair of winding rolls.