KR20140118071A

KR20140118071A - Turbulent flow generator for pre-treatment of ballast water for improvement of disinfecting function

Info

Publication number: KR20140118071A
Application number: KR1020130033319A
Authority: KR
Inventors: 이승복
Original assignee: (주)깨스코; (주) 엔케이텍
Priority date: 2013-03-28
Filing date: 2013-03-28
Publication date: 2014-10-08

Abstract

The present invention relates to a pre-treatment means of ballast water, which can improve the sterilization function of a sterilization device before sterilizing ballast water supplied from a sea-chest or a feed tank of a ship to a ballast tank with the sterilization device such as a UV sterilizer or an ozone injection device. More specifically, the present invention relates to a turbulent flow generator for pre-treatment of ballast water which improves the sterilization function of the ballast water by providing a turbulent flow generator which converts the flow of ballast water entered the sterilization device into turbulent flow using a fixated water propeller, thereby drastically increasing the possibility of contacting bacteria with UV or ozone gas. Furthermore, a physical sterilization plate, which performs pressurized sterilization and impact sterilization, is installed in the space within the turbulent flow generator, which corresponds to the front side of the water propeller, thereby enabling physical sterilization of bacteria at a certain level within the turbulent flow generator before sterilization treatment with UV or ozone gas. The turbulent flow generator for pre-treatment of ballast water reduces the treatment loads and the treatment costs in the sterilization device through a pre-treatment function of ballast water, and can provide an optimal treatment efficiency by maximizing the sterilization function.

Description

Technical Field [0001] The present invention relates to a turbulent flow generator for pre-treatment of ballast water,

Prior to the sterilization of the ballast water supplied from the sea chest or feed tank of the ship to the ballast tank by a sterilizing device such as an ultraviolet sterilizer or an ozone injection device, the composition of the turbulent flow by the water propeller, By providing a pretreatment means capable of performing physical sterilization treatment, it is possible to reduce the processing load and processing cost in the sterilizing apparatus through efficient pre-treatment of the ballast water, and to achieve the optimum treatment efficiency by maximizing the sterilizing function And a turbulence generator for a ballast water pretreatment.

In general, ballast water is installed on both sides of the bottom of a ship so that the ship can be prevented from being out of balance when the cargo is unloaded from the vessel or when the vessel is operated in a state where the amount of cargo loaded on the vessel is very small. Means freshwater or seawater for buoyancy adjustment to be filled in the ballast tank.

Since the above-mentioned ballast water contains various microorganisms such as bacterial bacteria and plankton contained in fresh water or seawater filled with ballast water, if it is discharged to the coast of another area without any treatment, There is a high possibility of causing serious marine pollution and destruction of ecosystems.

In other words, if marine organisms from other regions, such as microorganisms or algae, are introduced into new ecosystems, then this marine organism may be a natural flora of the region that does not have natural defenses against the new species It is very likely that animals will be destroyed, and if bacteria such as bacteria proliferate inside the ballast tank, they may cause various diseases in the area where ballast water is released.

Based on the above circumstances, in 1996, the United States enacted the national invasive species law, requiring the management and control of ballast water by stipulating the exotic species as an intruder, and amending the quarantine law in Australia, It carries out direct quarantine for import cargo as well as regulation.

On the other hand, the International Maritime Organization (IMO) concluded an international agreement in February 2004 and, from 2009, ordered to equip ships with the necessary equipment for disinfection of ballast water sequentially. In case of violation, And in addition to the IMO, the United States Coast Guard (USCG) applies to ships operating in all areas within the US exclusive boundary waters.

Therefore, all ships operating in foreign countries can only be operated with a ballast water treatment system approved by IMO and USCG. Therefore, various technologies for treating ballast water have recently been developed, There is a treatment system in which ultraviolet rays are irradiated to the flow path of water or ozone (O ₃ ) gas is injected into the ballast water to perform the sterilization treatment of the ballast water.

However, in the conventional ballast water treatment system, the flow of the ballast water flowing in the ultraviolet sterilizer or the flow of the ballast water flowing in the supply pipe connected to the ozone injecting device is not uniform in the horizontal direction ), The sterilizing performance of ballast water caused by ultraviolet rays or ozone gas is deteriorated.

In other words, in the case of the ultraviolet sterilization method, since the solid particles and the bacteria contained in the ballast water pass through the sterilizing area inside the ultraviolet sterilizer while maintaining a constant distribution, bacteria are distributed among the solid particles, The ultraviolet rays irradiated from the ultraviolet lamp are reflected or scattered by the upper and lower solid particles, so that the bacteria located between the solid particles are hard to be killed by contact with the ultraviolet rays.

On the other hand, even in the ozone sterilizing type treatment system in which ozone gas is injected into the ballast water, under the condition that the ballast water flowing along the supply pipe forms a constant water flow in the horizontal direction, the flow of the ozone gas injected into the ballast water In addition, since it proceeds in parallel with the flow of the ballast water, it is difficult to ensure sufficient mixing and sterilization performance of the ballast water and the ozone gas.

Considering the above factors, it is necessary to make the flow of the ballast water flowing into the sterilizing apparatus into a complicated turbulent flow so as to sufficiently secure the contact probability between the ultraviolet rays or the ozone gas and the bacteria and thus the sterilizing performance , The possibility of reducing the processing load and the processing cost in the sterilizing apparatus by possibly pre-sterilizing the bacteria contained in the ballast water in the course of making the flow of the ballast water into turbulent flow possible It can be seen as advantageous.

Korean Patent Laid-Open No. 10-2005-0104001 (public date: November 02, 2005) Korean Patent Publication No. 10-2010-0095306 (Published Date: August 30, 2010)

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a turbulent flow generator for generating a turbulent flow of a ballast water flowing into a sterilizing device such as an ultraviolet sterilizer or an ozone injection device using a fixed- The sterilizing performance of the ballast water is further improved by significantly increasing the probability of ultraviolet rays or ozone gas coming into contact with the bacteria while the internal space of the turbulence generator corresponding to the front side of the water flow propeller is subjected to pressure sterilization and shock sterilization It is possible to physically sterilize the bacteria inside the turbulence generator prior to the sterilization treatment by ultraviolet rays or ozone gas. Through the pretreatment function of such ballast water, the sterilizing apparatus The processing load and processing cost of the That to provide optimal processing efficiency by maximizing function will be as a technical problem.

According to an aspect of the present invention, there is provided a turbulence generator comprising: a tubular device casing connected to a ballast tank of a ship along a pipe for supplying ballast water; Wherein the water flow propeller comprises a central shaft disposed on a center line of the apparatus casing and a water flow blade connected to the center shaft and closely fitted to an inner circumferential surface of the apparatus casing, A plurality of physical sterilizing plates for performing sterilization by pressurization sterilization due to the reduction of the flow path and impact of the ballast water by the reduction of the flow path are additionally provided in the inside of the apparatus casing and each sterilizing plate is formed in the form of a disk having a predetermined thickness The inner peripheral surface of the casing of the apparatus is spaced at a predetermined interval from the front side of the water flow propeller Is installed.

The sterilizing plate is composed of a slit plate on which a flow path for flow reduction is formed and an impingement plate disposed on the rear side of the slit plate, Wherein the sterilizing plate is disposed at a position deviating from the path, and another application example of the sterilizing plate is to arrange two to four sterilizing plates having a plurality of linear flow passages formed at regular intervals in parallel with each other across the disc body, The arrangement is such that the straight flow passages formed in the sterilizing plate intersect with the straight flow passages of the adjacent sterilizing plate at an angle of 90 to 45 degrees.

According to the present invention, the flow of the ballast water flowing into the sterilizing device is formed into a turbulent flow, thereby greatly increasing the probability that ultraviolet rays or ozone gas are in contact with the bacteria and sterilizing the ballast water by the sterilizing device There is an effect of further improving the performance and a certain level of physical disinfection of the bacteria inside the turbulence generator before the sterilization treatment by the sterilization apparatus, and ultimately, the ballast water in a reasonable and economical manner It is possible to reduce the processing load and processing cost in the sterilizing apparatus through the pretreatment function and to ensure the optimum treatment efficiency by maximizing the sterilizing function.

1 is a side cross-sectional view of a turbulence generator according to the present invention;
2 (a) and 2 (b) are cross-sectional views taken along line AA and BB in Fig.
3 is an exploded perspective view showing another arrangement state of the sterilizing plate;
Fig. 4 is an exploded perspective view showing another arrangement state of the sterilizing plate; Fig.
5 is a schematic view showing the principle of physical sterilization by a sterilizing plate;
6 is a graph showing the correlation between the efficiency of removal by the pressure difference before and after the sterilizing plate and the economical efficiency.
7 is a piping diagram showing an example in which the turbulence generator according to the present invention is applied to a marine ballast water treatment system.
FIG. 8 is a schematic diagram for comparing the sterilization process using the turbulence generator of the present invention with the conventional case. FIG.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the turbulent flow generator 10 for pretreatment of ballast water for improving the sterilizing performance according to the present invention includes a front inflow pipe 12 and a rear inflow pipe 12, 13, a fixed water propeller 17 is inserted into the pipe-type device casing 11 connected to the ballast water supply pipe, and the water propeller 17 is disposed on the center line of the device casing 11 And a water flow vane 17b connected to the center shaft 17a and closely fitted to the inner circumferential surface of the body of the apparatus casing 11.

The water jet propeller 17 functions to create a turbulent flow of the ballast water by applying rotational force to the ballast water flowing through the inside of the apparatus casing 11, In the present invention, however, only a simple structure in which such a propeller is fixedly installed inside the apparatus casing 11 imparts a strong rotational force to the flow of ballast water passing through the propeller.

In order to smoothly flow and discharge the ballast water, an inlet pipe 12 is provided on the front and rear sides of the body of the apparatus casing 11, A connecting flange 12a for connection to the ballast water supply pipe is formed at the end of the inlet pipe 12 and the outlet pipe 13, ) 13a are provided.

In addition, a plurality (two in the figure) of physical elements (not shown) are provided in the device casing 11 of the turbulence generator 10 so as to additionally perform sterilization by pressure sterilization due to reduction in flow path and impact shock due to impact of ballast water. The sterilizing plate 16 is provided in the form of a disk having a predetermined thickness and is disposed at a predetermined distance from the front side of the water flow propeller 17, And is closely installed.

The sterilizing plate 16 and the water flow propeller 17 inserted into the pipe-shaped device casing 11 are prevented from being pushed backward by the flow pressure of the ballast water, It is preferable to form a stopping jaw or a mounting frame or the like capable of stably fixing the sterilizing plate 16 and the water flow propeller 17 and to easily install and replace the sterilizing plate 16 and the water flow propeller 17 It is preferable that the apparatus casing 11 is also disassembled and assembled.

For example, the device casing 11 may be divided into upper and lower semi-cylindrical portions, and then an assembling rim may be formed on the divided surface, or an expanding portion 11a including the inflow pipe 12 It is also possible to divide the shaft tube portion 11b including the discharge tube 13 from the body of the apparatus casing 11 and then install the assembly flange on each of the divisional surfaces and the sterilizing plate 16 and the water flow propeller 17 Are arranged in advance in correspondence with the positions before assembly of the apparatus casing 11. [

As shown in FIGS. 1 and 2, the sterilizing plate 16 includes a slit plate 14 in which a flow path 14a for reducing the flow path is formed, and a slit plate 14 disposed on the rear side of the slit plate 14 And the flow passage 15a formed in the impingement plate 15 constitutes the sterilizing plate 16 with the impingement surface 15b providing the impact surface 15b of the ballast water, The flow path 14a of the slit plate 14 is disposed at a position displaced from the flow path 14a.

In FIG. 2 (A), one linear flow passage 14a is formed at the center of the slit plate 14, and in FIG. 2 (B), the upper end and the lower end of the impingement plate 15 are provided with a straight- And the center side surface of the impingement plate 15 facing the flow passage 14a of the slit plate 14 provides the impact surface 15b, The plate 14 and the impingement plate 15 correspond to the simplest sterilizing plate 16 that can be applied to the present invention.

In other words, the slit plate 14 serves to pressurize the bacteria included in the ballast water by reducing the internal flow path of the apparatus casing 11, and the impingement plate 15 is disposed on the rear side of the slit plate 14 The shapes and arrangement states of the flow passages 14a and 15a provided in the slit plate 14 and the impingement plate 15 in accordance with this function are as follows: It can be adjusted in a wide variety of ways.

For example, a plurality of circular holes may be formed in the slit plate 14 as a flow passage 14a for reducing the flow path, while a plurality of circular holes corresponding to circular holes formed in the slit plate 14 are formed in the impingement plate 15 And a circular hole is arranged at a position other than the position where the circular hole is arranged in the position of the impact plate 15. In this case, if necessary, various fine irregular patterns are applied to the front side surface of the impingement plate 15, The function may be doubled.

It is also possible to provide two slit plates 14 and two impingement plates 15 on the rear side of each slit plate 14. In this case, pressurization sterilization and shock sterilization It is advantageous that the area of the flow passage 14a formed in the slit plate 14 is smaller than the area of the flow passage 15a formed in the impingement plate 15 so as to be alternately performed.

An example of application of the sterilizing plate 16 described above is to separately prepare two types of sterilizing plates 16 made up of the slit plate 14 and the impingement plate 15, So that the manufacturing cost of the sterilizing plate 16 may increase and the installation work may be confused with each other.

In order to prevent such a situation, as shown in Figs. 3 and 4, one sterilizing plate (four in the figure) linear flow passages 16a formed parallel to the disk body at predetermined intervals The sterilizing plates 16 are arranged at two to four positions along the inner space of the apparatus casing 11 so that the linear flow passages 16a formed in the respective sterilizing plates 16 are disposed adjacent to the sterilizing plates 16, More preferably, at a 90- to 45-degree angle with the linear flow passage 16a of the flow passage 16.

3, when the two sterilizing plates 16 are used, the flow passages 16a formed in the respective sterilizing plates 16 are crossed at an angle of 90 degrees, and three sterilization When the plate 16 is used, the flow passages 16a formed in the respective sterilizing plates 16 are crossed at a 60 degree angle. In the case of using the four sterilizing plates 16, The flow passage 16a formed in the flow passage 16 is intersected at a 45 degree angle.

When the above-described method is applied, the sterilizing plate 16 arranged on the foremost side in the drawing by using one kind of sterilizing plates 16 serves as a slit plate, and the remaining sterilizing plates The sterilizing plate 16 can be made to function as an impingement plate for providing the impact surface 16b, which makes it possible to apply the sterilizing plate 16 in a more economical and rational manner, Can be performed more easily without confusion.

5 shows the principle of pressure sterilization and shock disinfection using the sterilizing plate 16. The supply pressure of the ballast water introduced into the inside of the apparatus casing 11 is adjusted by the slit plate The primary pressurization sterilization of the bacteria B is carried out due to the pressure increase occurring in the space and the ballast is discharged along the flow passage 14a formed in the slit plate 14, The secondary impact shock disinfection of the bacteria (B) is performed in the process of passing through the rear impact plate (15) at a high speed.

The graph of FIG. 6 shows the removal efficiency of the bacteria B due to the difference between the pressure (high pressure) formed on the front side of the slit plate 14 and the pressure (low pressure) formed on the rear side of the impingement plate 15 in FIG. The removal efficiency of the bacteria B is increased as the pressure difference between the high-pressure side and the low-pressure side is large. However, the efficiency of removing the bacteria B is low, The optimum pressure difference considering both the removal efficiency and economical efficiency of the bacteria (B) is 0.8 kpa, and the bacterial (B) removal efficiency at this time is about 50%.

6, a sterilizing plate 16 performing the function of the slit plate 14 and a flow passage 16 formed in the sterilizing plate 16 performing the function of the impingement plate 15 It is preferable to adjust the area of the sterilizing plate 16 appropriately in accordance with the diameter and length of the body of the apparatus casing 11 and the processing capacity of the ballast water, But it is advantageous to set it within a range of at least 1 cm to at most 10 cm.

As the number of the sterilizing plates 16 is increased, the sterilization ability of the bacteria B by pressurization sterilization and shock sterilization is improved. However, the slit plate 14 disposed on the foremost side and the collision plate The sterilization efficiency of the bacteria B due to pressure sterilization and shock sterilization is exponentially decreased after the sterilization process is carried out through the sterilization chamber 15 so that it is economically feasible to arrange the number of sterilization plates 16 within a range of minimum 2 to maximum 4 to be.

7 shows the ultraviolet sterilization type ballast water treatment system 1 to which the turbulence generator 10 of the present invention is applied. The system includes a main supply pipe 2 for supplying ballast water to the ballast tank of the ship, A filter unit 4 installed in the main supply pipe 2 at a position past the ballast pump 3 and a main supply pipe 3 at a position past the filter unit 4, The turbulence generator 10 of the present invention is installed between the filter unit 4 and the ultraviolet sterilizer 5 and preferably between the ultraviolet sterilizer 5 and the ultraviolet sterilizer 5, The main supply pipe 2 is provided on the inlet side of the main pipe 2.

The filter unit 4 is installed to remove various suspended matters or foreign substances that can not be removed only by the sterilization treatment of the ballast water by ultraviolet rays. The filter unit 4 may be a filter or a wedge filter ), And the like, and an automatic backwashing type filter device provided with a function of dropping and discharging suspended matters or foreign substances attached to the surface of the filter is most preferable.

The ultraviolet sterilizer 5 is a typical example in which one or more ultraviolet lamps are inserted into the pipe-shaped body through which the ballast water flows, and the intensity of the ultraviolet light emitted from the ultraviolet lamp and the calorific value of the ultraviolet lamp And a control unit 7 for performing control of the ultraviolet sterilizer 5 is connected to the ultraviolet sterilizer 5.

On the other hand, an opening / closing valve (V) and a pressure gauge (PT) are provided in the main supply pipe 2 corresponding to the inlet and outlet sides of the filter unit 4, A bypass pipe 6 having an on-off valve V is connected to the main supply pipe 2 over a position past the outlet-side pressure gauge PT of the filter unit 4, An opening / closing valve (V) is also provided in the main supply pipe (2) corresponding to the inlet and outlet sides.

Accordingly, various kinds of foreign substances are primarily removed in the process of passing the ballast water supplied through the main supply pipe 2 according to the operation of the ballast pump 3 through the filter unit 4, and then the turbulence generator 10 of the present invention The bacteria B and the like included in the ballast water are sterilized in the process of sequentially passing through the ultraviolet sterilizer 5 and the ballast water having been subjected to the purifying and sterilization treatment is introduced into the ballast tank. The pressure gauge PT detects the flow path of the ballast water to the bypass pipe 6 side.

In addition, another bypass pipe 6a having an on-off valve V is provided from the position corresponding to the outlet of the ballast pump 3 to the position past the outlet opening / closing valve V of the ultraviolet sterilizer 5, The bypass pipe 6a serves as a final bypass passage for a situation in which the ballast water can not be supplied through the filter unit 4, the turbulence generator 10 and the ultraviolet sterilizer 5.

The pressure gauge PT is provided at a position just before the point at which the bypass pipe 6a is connected to the main supply pipe 2 for the operation of the opening and closing valve V provided in the bypass pipe 6a as the final bypass passage, It is preferable to provide a check valve C for blocking the backflow on the outlet side of the bypass pipe 6a. Is preferably a solenoid valve or a solenoid valve or an actuator type pneumatic valve whose opening and closing operation is automatically controlled by a pressure gauge (PT) or the like.

When the turbulence generator 10 of the present invention is applied to the ballast water treatment system 1 as described above, the flow of the ballast water is converted into turbulence by using the water propeller 17 before the ballast water is introduced into the ultraviolet sterilizer 5. The sterilizing performance of the ballast water can be further improved by significantly increasing the probability that the ultraviolet ray comes into contact with the bacteria (B), and this sterilization principle will be described in more detail with reference to FIG. 8 The following is an explanation.

8 (a) shows a sterilization process when the turbulence generator 10 of the present invention is not applied. The flow of the ballast water flowing into the ultraviolet sterilizer 5 is a constant flow of water in the horizontal direction, In this case, of the bacteria B in the ballast water flowing in the sterilizing area 5b, which is the internal passage of the ultraviolet sterilizer 5, the bacteria B distributed in the lower part of the solid particles P, The bacteria B flowing on the lower side of the bacteria B can not contact ultraviolet rays because the upper side solid particles P reflect or scatter the ultraviolet rays irradiated from the ultraviolet lamp 5a, The sterilizing ability of the ultraviolet sterilizer 5 is lowered.

8 (B) shows a sterilization process when the turbulence generator 10 of the present invention is applied. The flow of the ballast water flowing through the inside of the ultraviolet sterilizer 5 is applied to the flow propeller of the turbulence generator 10 In this case, solid particles (P) and bacteria (B) contained in the ballast water do not maintain a constant degree of distribution, and their position in the process of passing through the sterilization zone (5b) The ultraviolet rays irradiated from the ultraviolet lamp 5a are brought into contact with the bacteria B so that the probability of killing the bacteria B becomes very high.

In other words, among the bacteria B in the ballast water flowing in the sterilizing area 5b, which is the internal passage of the ultraviolet sterilizer 5, in the case of the bacteria B distributed at the lower part of the solid particles P The position of the ballast water with the solid particles P varies from time to time due to the irregular turbulent flow of the ballast water and the bacteria B distributed at the lower part of the solid particles P are exposed to the upper part of the solid particles P, The contact sterilization process is continuously and actively carried out throughout the sterilization zone 5b of the ultraviolet sterilizer 5 so that the bactericidal performance of the bacteria B can be significantly improved as compared with the conventional ultraviolet sterilization method.

In addition, by additionally providing a physical sterilizing plate 16 for performing pressure sterilization and shock sterilization in the inner space of the apparatus casing 11 corresponding to the front side of the water jet propeller 17, the ultraviolet sterilizer 5 It is also possible to physically sterilize the bacteria (B) within the turbulence generator 10 prior to the disinfection treatment by the ballast water treatment apparatus 10, and through the pretreatment function of such ballast water, the treatment load and the treatment cost in the ultraviolet sterilizer 5 And to provide an optimum treatment efficiency by maximizing the sterilizing function.

7 is a typical example in which the turbulence generator 10 of the present invention is applied to the ballast water treatment system 1 using the ultraviolet sterilizer 5. However, in addition to the ballast water treatment system 1 using the ultraviolet sterilizer 5, The turbulence generator 10 according to the present invention can also be applied to an ozone sterilization type treatment system in which ozone gas is injected into the ballast water. In this case, the ultraviolet sterilizer 5 is replaced by the treatment system 1 shown in Fig. It can be interpreted that the ozone injection device is installed.

Lastly, since the turbulence generator 10 of the present invention is also used for treatment of ballast water as seawater, a corrosion resistant material capable of ensuring durability in seawater is used, and the apparatus casing 11, the sterilizing plate 16, The device casing 17 may be made of a corrosion resistant metal material and the sterilizing plate 16 and the water flow propeller 17 may be made of a plastic material having excellent mechanical strength. I will reveal.

1: processing system 2: main pipe 3: ballast pump
4: filter unit 5: ultraviolet sterilizer 5a: ultraviolet lamp
5b: sterilization zone 6,6a: bypass tube 7: control unit
10: turbulent flow generator 11: device casing 11a:
11b: shaft portion 12: inlet pipe 12a, 13a: connecting flange
13: discharge pipe 14: slit plate 14a, 15a, 16a:
15: collision plate 15b, 16b: collision surface 16: sterilizing plate
17: Water flow propeller 17a: Center shaft 17b: Water flow blade
V: opening / closing valve PT: pressure gauge C: check valve
B: bacteria P: solid particles

Claims

A pipe type device casing 11 connected to a ballast tank of a ship along a pipe for supplying ballast water to the ballast tank and a water flow propeller 17 fixedly inserted in the device casing 11,
The water flow propeller 17 includes a center shaft 17a disposed on the center line of the apparatus casing 11 and a water flow vane 17b connected to the center shaft 17a and closely fitted to the inner peripheral surface of the apparatus casing 11. [ Wherein the turbulent flow rate of the turbulent flow in the turbulent flow channel is controlled by the turbulent flow rate.

The apparatus according to claim 1, wherein a plurality of physical sterilizing plates (16) for performing pressure sterilization by collapsing the flow path and impact sterilization by collision of ballast water are additionally installed in the apparatus casing (11)
Characterized in that each sterilizing plate (16) is in the form of a disk having a predetermined thickness and is closely attached to the inner circumferential surface of the device casing (11) at a predetermined distance from the front side of the water flow propeller (17) Turbulence generator for ballast water pretreatment for improvement.

The sanitary disinfection apparatus according to claim 2, wherein the sterilizing plate (16) comprises: a slit plate (14) having a flow passage (14a) for reducing a flow path; (15), which is provided on the upper surface
The flow passage 15a formed in the impingement plate 15 is formed at a position displaced from the flow passage 14a of the slit plate 14 in order to secure the impact surface 15b. Turbulence generator for ballast water pretreatment.

The sterilization apparatus according to claim 2, wherein the sterilizing plate is formed in parallel with a plurality of linear flow passages (16a) across the disc body at predetermined intervals, and the sterilizing plate (16) Are arranged in two to four along the space,
The arrangement of the sterilizing plates 16 is such that the linear flow passages 16a formed in the respective sterilizing plates 16 intersect with the linear flow passages 16a of the adjacent sterilizing plates 16 at an angle of 90 to 45 degrees. Wherein the turbulent flow rate of the turbulent flow in the turbulent flow channel is controlled by a turbulent flow rate.