JPH07170901A - Prevention method of marine organism adhesion and device therefor - Google Patents

Abstract

PURPOSE:To prevent the adhesion of marine organisms to fixed or moving structures immersed in sea water all the time, by using a waste heat of an engine, etc., without using any repellent such as a ship bottom paint, etc., containing a poisonous material causative of an environmental disruption. CONSTITUTION:An inside surface temperature of a water inlet 20 is kept at 20-60 deg.C, preferably 35-55 deg.C by using secondary cooling water heated by a waste heat of an engine, circulating from a secondary cooling water tank. The reason of limiting the temperature range is that a temperature of 20 deg.C or lower is not effective for preventing the organism adhesion even in winter, and that a temperature of higher than 60 deg.C causes a saturation of effectiveness, and at the same time, a structural material of the water inlet 20 is necessary to be elaborated and an inefficiency in energy utilization will result.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for preventing adhesion of marine organisms, and more particularly to a method and apparatus for preventing adhesion of warmed marine organisms utilizing engine waste heat and the like.

[0002]

2. Description of the Related Art Conventionally, in fixed or moving structures that are constantly immersed in seawater, such as light buoys, floating piers, ships, etc., marine organisms such as shellfish and algae are inevitably attached to the portion under the water. This tendency is particularly noticeable in fixed structures, but even in ships, similar marine organisms adhere to the ships while they are moored, which stains the surface of the hull and inevitably increases the running resistance of the hull, which is disliked. For this reason, it is necessary to land or dock the hull once a year, to remove attached marine organisms and to repaint so-called marine paint (ship bottom paint) at great expense and time. However, since this marine paint contains an organic Sn-based repellent for marine organisms, there is a problem in that it accumulates in the sea or undersea organisms and causes a destruction of the natural environment or deterioration of the food chain.

As a countermeasure, for example, a paint using cuprous oxide instead of organic Sn, such as Marine Star (registered trademark?) Manufactured by China Paint Co., Ltd., or a zinc-based paint has been developed and used, but it is still complete. It cannot be called a means.

Conventionally, depending on the structure, the vicinity of the primary cooling water intake port of the engine may be attached to marine organisms in the entire pipe up to the intermediate valve or strainer depending on the structure.
It could also cause overheating of the engine.

Further, as a method for preventing adhesion of marine organisms which causes the blockage of these pipe systems, there are chemical treatment methods such as a free chlorine injection method, but these are difficult to adopt because of problems in equipment operation and safety. Therefore, a tablet-type anti-adhesion agent for marine organisms has been developed in which organic nitrogen compounds and the like are hardened with natural resin. This is placed and installed in a primary cooling water strainer, etc., and is useful as it is, but it is troublesome to handle because it is necessary to constantly supply an appropriate amount. Specific examples of the marine organisms referred to in the present invention are shellfish such as mussels, oysters and barnacles, and mainly green algae.

Therefore, the present inventor has advanced the ecological observation of marine organisms adhering to the hull and the like, and has found a tendency that these marine organisms do not adhere to marine structures having a constant surface temperature range. As a result, the present invention has been achieved.

[0007]

OBJECT OF THE INVENTION The object of the present invention is to prevent the adhesion of marine organisms without using repellents such as ship bottom paints containing toxic substances that lead to environmental damage.

Another object of the present invention is to prevent marine life from adhering to the hull while saving energy.

[0009]

According to the present invention, a method for preventing adhesion of marine organisms (claim 1), characterized in that the surface temperature of a fixed or moving structure which is constantly immersed in seawater is kept at 20 to 60 ° C, The power ship or a sailboat with an inboard type auxiliary engine, the heat source is a resistance heating element or thermocouple supplied with electric power from a power source, and the heating point is near the engine cooling water intake port. The marine organism adhesion prevention method (claim 2), the moving structure is a diesel engine ship,
The heat source is engine waste heat, and the heating location is near the primary cooling water intake port. The method for preventing marine organisms from adhering (claim 3) according to claim 1, wherein a part of the secondary cooling water system of the diesel engine is used. A marine organism attachment prevention device (Claim 4) that circulates the secondary cooling water that has been bypassed and is heated by a pump to heat the vicinity of the primary cooling water intake, and directly from the secondary cooling water system of the diesel engine. Alternatively, a marine organism attachment preventing device (claim 5) and secondary cooling, in which waste heat recovered through a heat exchanger is sent using a heat pipe and / or a heat pump to heat the vicinity of the primary cooling water intake port (claim 5) The marine organism adhesion preventing device (Claim 6) according to claim 3, wherein the water system is a secondary cooling water system including a fresh water gravity tank.

The present invention will be described in detail below with reference to examples.

[0011]

1 is a circuit diagram of an embodiment of the present invention in which secondary engine cooling water is used for heating, FIG. 2 is a circuit diagram of an embodiment using a heat pipe, and FIG. 3 is an embodiment circuit using a heat pump. 4 and 5 are circuit diagrams of an embodiment using a resistance heating element or a thermocouple.

In FIGS. 1, 2, 3 and 4, 1 is an engine, 2
Is a secondary cooling water (fresh water) pipe, 3 is a secondary cooling water tank,
4, 5 are pumps, 6 are pipes for heating the primary cooling water intake, 7
Is a power supply, 8 is a two-way valve, 9 is primary cooling water (seawater) inlet side piping, 10 is primary cooling water (seawater) outlet side piping, 12 is a heat pipe, 14 is a heat pump piping, 15 is a heat pump, 16 is a switch (Or automatic temperature controller), 1
7 is electrical wiring, 18 is a resistance heating element (or thermocouple),
20 is a secondary cooling water heating type primary cooling water intake, 21 is a heat pipe heating type primary cooling water intake, 22 is a heat pump heating type primary cooling water intake, and 23 is a resistance heating type secondary cooling water intake It is a mouth.

In FIG. 1, the water intake 20 is kept at 20 to 60 ° C. by the secondary cooling water heated by the engine waste heat circulating from the secondary cooling water tank. However, since the primary cooling water only passes through the short intake port 20, it is hardly heated by itself, and the secondary cooling water of the engine can be sufficiently cooled through the heat exchanger 3.

Note that the temporary cooling water intake port heating pipe 6 may be made to directly divert from the pump of the engine or the secondary cooling water pipe in order to use the waste heat of as high temperature as possible.
In order to utilize the residual heat after the engine is stopped, it is preferable to circulate it from the secondary cooling water tank (fresh water gravity layer) by an additional pump 5.

Even when the engine is stopped for a short time, such as a ferry boat, the primary intake may cool and marine organisms may adhere to it during the berth after the last flight, so the latter is better than the former. Is good.

FIG. 2 is a circuit diagram of another embodiment for heating the primary cooling water intake port 21 by transferring the engine waste heat from the secondary cooling water tank 3 using the heat pipe 12. in this case,
Although the heat pipe is expensive, there is an advantage that the maintenance cost is low because the pump and the electric energy for rotating the pump are not required.

FIG. 3 is a circuit diagram of another embodiment using a heat pump. The heat pump draws heat from the secondary cooling water that has become lower in temperature than the intake port, and removes heat from the intake port 22 to 20-6.
There is a benefit that can be heated to 0 ℃.

FIG. 4 is a circuit diagram of an electrothermal type embodiment using a resistance heating element or a thermocouple.

In FIG. 4, a current flows from a DC power source 7 such as a lead-acid battery or a generator driven by an auxiliary engine through a switch or an automatic temperature controller 16 through a water intake port 23 to a resistance heating element or a thermocouple, and water intake Heat mouth 23. Needless to say, a tributary power source may be used in the case of a resistance heating element. The automatic temperature control device detects the temperature of the inner surface of the water intake by a temperature sensor (not shown), calculates the preset temperature in an analog or digital manner, and controls the current ON-OFF or analog to ensure this. is there.

Even in the other embodiment shown in FIG. 1, automatic temperature control of the water intake can be performed. For example, in the embodiment of FIG. 1, the surface temperature inside the water intake is To, the measured temperature is the surface temperature deviation inside the Ti water intake, ΔT = To−Ti, the temperature of the secondary cooling water is T ₂ , the discharge amount of the pump 5 per hour. When V is V, the valve 8 and / or the pump 5 may be controlled so that T ₂ becomes approximately ΔT.

In the case of FIG. 3, the principle is the same except that the medium is not the secondary cooling water but Freon gas, ammonia or CO ₂ gas.

However, it goes without saying that the electrothermal type as shown in FIG. 4 is the easiest to control.

Next, the reasons for limiting the heating temperature of the water intake will be described. That is, the surface temperature of the water intake port is preferably 20 to 60 ° C, and more preferably 35 to 55 ° C. The reason for the limitation is that if the temperature does not exceed 20 ° C, there is no effect of preventing biofouling even in winter, and if the temperature exceeds 60 ° C, the effect saturates. It is uneconomical. The range of 35 to 55 ° C is most effective regardless of the seawater temperature. The temperature range of 20 ° C or higher and lower than 35 ° C is mainly effective in the winter when the seawater temperature is low, but the range of 35 ° C to 55 ° C is effective also in the summer and exhibits a stable biofouling prevention effect throughout the four seasons. Is.

In the case of a fixed structure such as a jetty or a light buoy, if there is a power source and a hot water source, the surface contacting with seawater can be heated to 20 to 60 ° C. according to the embodiment of FIGS. It can prevent the adhesion of marine life.

[0025]

By carrying out the present invention, all the above objects can be achieved. That is, it is possible to prevent the adhesion of marine organisms without using a repellent such as a ship bottom paint containing a toxic substance that leads to environmental damage. In addition, it is possible to prevent the adhesion of marine life to the hull while saving energy.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention in which engine secondary cooling water is used for heating.

FIG. 2 is a circuit diagram of an embodiment using a heat pipe.

FIG. 3 is a circuit diagram of an embodiment using a heat pump.

FIG. 4 is a circuit diagram of an embodiment using a resistance heating element or a thermocouple.

[Explanation of symbols]

 1 engine 2 secondary cooling water (clean water) piping 3 secondary cooling water tank 4 pump 5 pump 6 primary cooling water intake port heating piping 7 power supply 8 two-way valve 9 primary cooling water (seawater) inlet side piping 10 primary cooling Water (seawater) outlet side pipe 12 Heat pipe 14 Heat pump pipe 15 Heat pump 16 Switch (or automatic temperature control device) 17 Electric wiring 18 Resistance heating element (or thermocouple) 20 Secondary cooling water Heating type primary cooling water intake 21 Heat pipe heating type primary cooling water intake 22 Heat pump heating type primary cooling water intake 23 Resistance heating type secondary cooling water intake

Claims (6)

[Claims] 1. A method for preventing adhesion of marine organisms, characterized in that the surface temperature of a fixed or moving structure which is constantly immersed in seawater is maintained at 20 to 60 ° C. 2. The moving structure is a power ship or a sailboat with an inboard type auxiliary engine, the heat source is a resistance heating element or a thermocouple to which power is supplied from a power source, and the heating point is cooling water intake for engine. The method for preventing adhesion of marine organisms according to claim 1, which is in the vicinity of the mouth. 3. The method for preventing adherence of marine organisms according to claim 1, wherein the moving structure is a diesel engine ship, the heat source is engine waste heat, and the heating location is near the primary cooling water intake port. 4. A marine organism adhesion prevention system, wherein a secondary cooling water heated by bypassing a part of the secondary cooling water system of a diesel engine is circulated by a pump to heat the vicinity of the primary cooling water intake port. apparatus. 5. Waste heat recovered directly from a secondary cooling water system of a diesel engine or via a heat exchanger is sent using a heat pipe and / or a heat pump to heat the vicinity of the primary cooling water intake port. Marine organism adhesion prevention device. 6. The marine organism adhesion preventing device according to claim 3, wherein the secondary cooling water system is a secondary cooling water system including a fresh water gravity tank.