JPH0224570B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a trap for removing harmful zooplankton such as cutworms and sea lice that are parasitic on fish living in ponds or fishponds. It is something. [Prior art] Squid insects that have traditionally lived in ponds or aquaculture ponds,
A method is used to kill insect larvae and the like by spraying a pond with a drug such as Mazothene (manufactured by Nippon Tokushu Noyaku Co., Ltd.; trade name: Mazotin), which contains trichlorfone as the main ingredient. However, the method of using drugs has the disadvantage that it can have a negative impact on the fish due to side effects such as causing body abnormalities in the parasitic host fish, and the drug is used up and must be constantly replenished. . [Problems to be Solved by the Invention] The present invention provides a trap that traps zooplankton harmful to fish living in ponds or fishponds without causing side effects to the fish. [Means for Solving the Problem] As a result of research to solve this problem, the present inventor found that zooplankton is within a substantially constant size range, and that accordingly, the water in the pond or fish pond should be reduced. The present invention was based on the knowledge that if the fish is passed through a filter with a mesh size of 50μ to 120μ, the phytoplankton that serves as food will remain, and only the harmful zooplankton, such as the squid that parasitizes fish, will be physically removed. completed. [Function] The present invention allows zooplankton-containing water to be
A method for trapping zooplankton and a trap for the same, characterized in that the filter is covered with a net having a diameter of 50 μm to 120 μm or a ceramic body is used as a filter. The mesh can be made of plastic, carbon, stainless steel or metal or alloy with corrosion-resistant plating, or of ceramic. Next, embodiments of the present invention will be described with reference to the drawings. In Fig. 1, 1 is the main body of the plankton trap, and the outer peripheral surface of the hollow skeleton body 2 has openings of 50 to 120 μm.
A net having the following is covered as the filter 3. The cross-sectional shape of the hollow skeleton may be circular, oval, triangular, quadrilateral, polygonal, or the like. Lids 4 and 5 are fixed to both ends of the zooplankton trap body 1 , and the lid 4 is connected to a sewage supply pipe 6 for feeding wastewater from a pond or fishpond to the plankton trap body by a pump 16. . 17 is a support stand. To capture zooplankton in sewage, water is pumped up from pond A by pump 16 and then connected to sewage supply pipe 6.
If it is press-fitted into the plankton trap 1 through
Zooplankton in the wastewater is captured by the filter 3 when the wastewater passes from the inside of the filter to the outside, and is discharged into the pond B as clean water. FIG. 3 is a longitudinal sectional view of a zooplankton trap according to another embodiment of the present invention. 1a is a zooplankton trap, and a filter 3a whose outer circumferential surface is covered with a mesh having an opening of 50 to 120μ is inserted into a case 21a, and
The ends of the filter 3a and the case 21a are fixed to the lids 4a and 5a, respectively. To securely attach the filter 3a and the case 21a at their ends, for example, the ends of the filter 3a can be welded to the lids 4a and 5a, respectively, or the ends of the case and the filter can be provided with a brim and overlapped. Conventional means such as inserting a packing and tightening bolts are used between the lid and the lid. 6a is a waste water supply pipe connected to a chamber between the case 21a and the filter 3a, and 7a is a purified water discharge pipe connected to the lid at the other end of the filter. To purify wastewater using the zooplankton trap 1a , the sewage is pumped up and passed through the sewage supply pipe 6a to the zooplankton trap 1a .
If water is sent into the tank a, the wastewater first enters the space between the case 21a and the filter 3a, and then flows into the drain pipe 7.
Since sewage a is connected only to the inside of the filter, in order to be discharged, the sewage passes through the net of the filter 3a, and at this time, zooplankton is captured by the sewage, and the sewage becomes purified water and is discharged from 7a. FIG. 4 is a longitudinal sectional view of another embodiment of the zooplankton trap, in which a sewage supply pipe 6b equipped with a pressure gauge 8b is provided on one end side of the zooplankton trap main body 1b ; , a purified water discharge pipe 7 is provided on the other end side of the plankton trap main body 1b .
b, and a case 21b with a removably fixed transparent plate window 9b on the top of the main body, a drain valve 18b for draining water on the bottom, and a support stand 17 on the bottom; A plurality of filters 3b, 3'b, . The filters 3b, 3'b, . . . are hollow bodies covered with a mesh having openings of 50 to 120 μm, and are reinforced with metal, plastic, or ceramic as necessary. Reference numeral 6b is a supply pipe for sewage mixed with zooplankton, through which the sewage is supplied to the zooplankton trap 1b . Each of the filter lids 5b, 5b'...
A hole is provided, and 11b is a filter fixing plate, and an annular body 12 that fits into a hole in the filter lid 5b is provided.
b is provided, and the annular body 12b and the fitting hole 20b of the filter lid are fitted to fix one end of the filter, and the other end is provided between the lid 4b and the filter fixing plate 10b. It is pressed and fixed by a spring 13. In addition, the lid 4b has a filter fixing plate 10b with one or more holes, and a fixed or fixed bolt is inserted through the filter fixing plate 10b, and the tip of the protruding bolt shaft is fitted with the ring-shaped body at the other end and the hole. The filter is surrounded by a spring for elastically connecting the fitted filters, and the filter is held tightly in the case by being pressed by a pressure gasket provided at the tip of the bolt. To capture zooplankton from the wastewater, the wastewater pumped up by a pump is sent to the zooplankton trap 1b through the wastewater supply pipe 6b, and the wastewater flows in the direction of the arrow shown in the drawing and passes through the filter. The zooplankton is captured by the filter and purified to become water, which is then passed through the purified water discharge pipe 7b.
more excreted. That is, first, the wastewater flows from the sewage supply pipe 6b to the central portion of the filter fixing plate 10b through one or more holes 15b. At this time, the filter fixing plate 11b on the drain side has no holes, and the inside and outside of the filter are connected only by the annular body 12b, so the water that enters from the supply pipe must be filtered in order to exit. At this time, the zooplankton is captured by the mesh of the filter, and the water that has passed through the filter becomes purified water with less zooplankton and is discharged from the purified water discharge pipe 7b. In addition, there is a removable window 9b made of a transparent plate at the top of the case for replacing the filter and observing the dirtiness.A rubber gasket is provided to prevent water from leaking due to water pressure. It is fixed. Note that this fixing method is not limited to screws, but any other method may be used as long as it prevents water leakage and is detachable. To replace this filter, remove the window, push the filter toward the spring to release the airtight state, and remove the other end by pulling it out of the annular hole. [Effect] The present invention physically traps harmful zooplankton by passing wastewater inhabited by fish containing zooplankton through a filter with pores of 50 to 120 μm, and the treated water becomes In addition, the mesh size is 50 μ to 120 μ.
Therefore, phytoplankton and bacteria useful for fish pass through the filter mesh, so the treated water can improve the water quality for fish. [Example] After artificially hatching squid beetles by putting water into an aquarium of approximately 0.5 t, a submersible pump connected to a 75 micron filter was operated to circulate the water and the reduction of squid beetles over time was investigated. . The results obtained are shown in Table 1. The measurement was based on the presence of squid in the raw water when the device was in operation as 100%.
After 10 hours of operation of the device, the survival rate of squid caterpillars is
It became 20-30%, and 5-10% in 24 hours. 【table】

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a zooplankton trap according to one embodiment of the present invention, FIG. 2 is a perspective view of the filter shown in FIG. 1, and FIG. 3 is a view of a zooplankton trap according to another embodiment of the present invention. FIG. 4 is a longitudinal sectional view of a zooplankton trap according to another embodiment of the present invention, and FIG. 5 is a right side view of FIG. 4 with the right side of the case removed. 1, 1a, 1b: Main body of zooplankton trap, 2, 2a, 2b: Hollow skeleton, 3, 3a, 3
b, 3'b...: Filter, 4, 4a, 4b,
4'b...: Lid, 5, 5a, 5b, 5'b...: Lid,
6, 6a, 6b: Sewage supply pipe, 7a, 7b: Clean water discharge pipe, 8b: Pressure gauge, 9b: Peephole, 10
b, 11b: filter fixing plate, 12b: annular body, 13b: spring, 15b: hole, 16: pump, 17, 17b: support stand, 18b: drain valve, 20b: fitting hole, 21a, 21b: case.

Claims (1)

[Scope of Claims] 1. Waste water from a pond or fish farm where fish live
A method for capturing zooplankton in wastewater, which is characterized by passing it through a 120μ mesh filter. 2. The method for trapping zooplankton according to claim 1, wherein the filter is a stainless steel net, a carbon fiber net, a plastic net, or a porous ceramic body. 3 A lid is provided at each end of a filter consisting of a hollow body whose outer circumferential surface is covered with a mesh having a mesh size of 50 to 120 μm or a porous ceramic body,
Furthermore, one lid may be provided with a hole to open the waste water supply pipe inside the filter to allow the waste water to pass from the inside of the filter to the outside, or one or more hollow bodies may be provided in the case so that the outer peripheral side is 50 mm. A filter covered with a mesh of ~120μ is fixed and sealed with filter mounting plates provided at both ends of the case, and a sewage supply pipe is connected to the chamber between the case and the filter.
The zooplankton trap is further characterized in that a purified water discharge pipe is connected from the inside of the filter to the lid at the other end to allow wastewater to pass from the outside to the inside of the filter. 4. The zooplankton trap set forth in claim 3, wherein the filter is a hollow body covered with plastic, carbon fiber, or stainless steel mesh, or the filter is a porous ceramic body. 5. An animal according to claim 3, characterized in that an L-shaped brim is provided at each end of the filter and the case, and the brim is provided with packing and bolted to fix the filter to the filter fixing plate. Sexual plankton trap. 6. The zooplankton trap set forth in claim 3, wherein the filter and the filter fixing plate are removably held together by a spring.