JP2000186549A - Engine cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine cooling system having improved heat efficiency. SOLUTION: An engine cooling system comprises an engine body cooling system to cool the given cooling part of the body of an engine 1; and a charge cooling system to cool supply air in a pressure state to be supplied to the engine 1. A charge cooler 4 arranged at the charge cooling system comprises two heat-exchange parts of one being a heat-exchange part 4A on the low temperature side and the other being a heat-exchange part 4B on the high temperature side. Heat recovery efficiency is improved such that heat is recovered from two cooling media of one being a cooling medium flowing through an engine body cooling system and the other being a cooling medium flowing through the heat-exchange part 4B on the high temperature side of the charge cooler 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a generator, a pump,
The present invention relates to a cooling system for a large engine that drives a compressor or the like, and more particularly to a novel engine cooling system that improves heat recovery efficiency.

[0002]

2. Description of the Related Art Taking a conventional power generation system using a diesel engine or a gas engine as an example, an engine 1 and a generator 2 connected to the engine 1 as shown in FIG. The generator 2 is operated by driving the engine 1 to generate required electric power. A main body cooling system for cooling a required cooling portion of the engine main body for preventing the engine 1 from overheating, and a fuel supplied to the engine 1 And a supply air cooling system that increases the fuel density by cooling a mixed fluid of air and air.

The engine body cooling system includes a cooling water passage 1a formed in a required cooling portion of the engine body and a primary side passage 3a formed in the first heat exchanger 3 for heat recovery.
The pipes L1, L2, L2 are circulated through the pump P1.
The first cooling water circulation path is formed by the first cooling water flowing through the flow path 1a of the required cooling unit of the engine, and the first cooling water that has been heated is cooled by the first cooling water. The first heat exchanger 3 is supplied to the first heat exchanger 3, where the secondary flow path 3 b in the first heat exchanger 3
Heat exchange with the water to be treated supplied to the
The hot water of about ° C. is supplied from the pipe L5 to the hot water tank. As a result, overheating of the engine body is prevented, and a part of the external heat radiation from the engine body is recovered as hot water.

On the other hand, the fuel supplied to the engine 1 is mixed with air and supplied to the supercharger 5 from the pipe G1 at 1.5 kg / cm ^2.
The pressure is increased to about 170 ° C., the temperature is increased to about 170 ° C., and the temperature is cooled to a predetermined temperature by a supply air cooling system from a pipe G2 and supplied to the engine from a pipe G3. This is because the output of the internal combustion engine is greatly affected by the amount of air consumed per unit time, and therefore, the amount of air per unit volume is increased by pressurizing the supercharger 5 before supplying the engine to the engine. It is. On the other hand, as a result of being pressurized by the supercharger 5, the temperature becomes high. If the temperature is supplied into the engine as it is, knocking is likely to occur in the engine, and abnormal stress is generated in the engine to cause engine trouble. . Therefore, by cooling the mixed fluid of the fuel and air, which has been pressurized to a high temperature, before supplying the engine, the volume of the mixed fluid is reduced, the fuel content per unit volume is increased, and the output of the engine is increased. Is increased, and engine troubles that occur when the mixed fluid is supplied in a high temperature state are prevented.

The supercharger 5 is driven by an exhaust gas turbine 6 disposed in a high-temperature and high-pressure exhaust gas line G 4 discharged from the engine 1. Is supplied to the mixed fluid through the supercharger 5, and the exhaust gas whose temperature and pressure are reduced is supplied from a pipe G5 to an exhaust gas heat recovery system for further heat recovery or is discharged directly to the atmosphere. .
As a method of driving the supercharger 5, there is also a method of driving using the rotation output of the engine 1 instead of the exhaust gas turbine. In this case, a part of the output energy of the engine is charged by the supercharging. That is, it is given to the mixed fluid through a vessel.

Further, an air-supply cooler 4 for cooling the high-temperature mixed fluid is disposed in the air-supply cooling system. A second cooling water circulation path including a pump P2 and pipes L6 to L8 is formed so as to circulate between the primary heat exchanger 7 and the primary flow path 7a formed in the two heat exchangers 7. The second cooling water, which cools the mixed fluid and is heated by the second cooling water flowing through the cooling water flow path 4a, is supplied from the pipe L8 into the second heat exchanger 7, where the second cooling water is cooled. The cooling water is cooled to a predetermined temperature by the third cooling water flowing through the secondary flow path 7b in the second heat exchanger 7, and is returned to the air supply cooler 4 via the pipe L6, the pump P2, and the pipe L7. ing. On the other hand, the third cooling water, which has been heated by exchanging heat with the second cooling water in the second heat exchanger 7, is supplied from the pipe L11 to the cooling tower 8 and emits heat to the atmosphere to be cooled to a predetermined temperature. Pipe L
9. The pump P3 and the pipe L10 return to the second heat exchanger 7.

[0007]

In such a conventional engine cooling system, there is no problem with the cooling of the engine itself and the cooling of the mixed fluid of fuel and air, but heat is recovered from the engine body. The cooling water, which is only the heat energy from the cooling system and is heated in the secondary flow path 7b of the second heat exchanger 7 of the supply air cooling system, is sent from the pipe L11 to the cooling tower 8 and enters the atmosphere. Emitting heat. Accordingly, in the air supply system, while recovering a part of the energy held by the exhaust gas as a high-temperature and high-pressure mixed fluid through the exhaust gas turbine 6 and the supercharger 5, the recovered heat is supplied to the air-supply heat exchanger. Since the heat is released from the cooling tower 8 to the atmosphere via the fourth heat exchanger 4 and the second heat exchanger 7, the heat recovery from the cooling system is not performed at all. Similarly, when the supercharger 5 is mechanically driven by the output of the engine 1, a part of the engine output energy is supplied to the mixed fluid through the supercharger, and the mixed fluid is collected from the cooling tower 8 without being recovered. It will be released inside.

FIG. 6 is a conceptual diagram showing the energy efficiency of the above-described power generation system. When the supplied fuel energy is 100, approximately 36% is recovered as power from the generator, and the pipe L5 The energy recovered from the system as hot water is about 29%, the energy released out of the system as exhaust gas from the pipe G5 is about 30%, and the energy released from the cooling tower 8 to the atmosphere is about 5%. The overall energy efficiency recovered as water is about 65%. 5 and 6 show an example in which waste heat recovery from the pipe G5 is not performed. However, when heat recovery from exhaust gas is performed, energy efficiency is further improved. Nor.

On the other hand, due to recent global environmental problems, a direction to suppress the emission of carbon dioxide has been indicated. For this purpose, effective utilization of energy and a practical measure of energy saving measures by this are required. Improving energy efficiency is urgently needed.

The present invention has been made in view of the problems of the prior art and global environmental problems, and aims to provide a simple system for promoting effective use of energy and energy saving measures by improving an engine cooling system. Things.

[0011]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above-mentioned viewpoint, and is characterized by an engine body cooling system for cooling a required cooling portion of the engine body, and In an engine cooling system having an air supply cooling system for cooling an air supply in a pressurized state to be supplied, an air supply cooler disposed in the air supply cooling system includes a low-temperature side heat exchange section and a high-temperature side heat exchange section. And heat recovery from both the cooling medium flowing through the engine body cooling system and the cooling medium flowing through the high-temperature side heat exchange section of the charge air cooler. It is in.

As a specific method, the engine main body cooling system includes a first refrigerant flow path formed in a required cooling portion in the engine and serving as a flow path of a first cooling medium, and heat generated by the first cooling medium. A heat recovery unit that performs recovery, wherein the supply air cooling system has a low-temperature side heat exchange unit having a second refrigerant flow path through which a second cooling medium flows, and a third refrigerant flow through which the first cooling medium flows A supply air cooler comprising two heat exchange sections with a high-temperature side heat exchange section having a path, and cooling the second cooling medium flowing through the second refrigerant flow passage in the low-temperature side heat exchange section to a predetermined temperature. A cooling unit for cooling the supply air in the pressurized state by the two cooling media of the first cooling medium and the second cooling medium. The third refrigerant flow path and the third formed in the high-temperature side heat exchange section of the charge air cooler A system in which the first cooling medium is circulated through the third cooling medium flow path and heat is recovered from both the engine body and the air supply by the first cooling medium. There is.

In the above system, the first cooling medium is circulated by first cooling a required cooling portion of the engine main body through a first refrigerant flow path of the engine main body cooling system. A first method in which the supply air is cooled through the third refrigerant flow passage formed in the high-temperature side heat exchange section of the cooler, and then supplied to the heat recovery section; The pressurized air supply is cooled through the third refrigerant flow passage formed in the high-temperature heat exchange section of the heat exchanger, and then required cooling of the engine main body is passed through the first refrigerant flow passage of the engine main body cooling system. After cooling the part,
There are two types of the second type in which the heat is supplied to the heat recovery unit.

In the case of the first type, cooling water is selected as the first cooling medium. In the case of the first type, the first cooling medium boils in a heat exchange process with the supply air in the third refrigerant flow path of the supply air cooler. Also, in the case of the second type, in the heat exchange process with the required cooling portion of the engine main body in the first refrigerant flow path of the engine main body cooling system, the first It is also possible to omit the cooling medium circulation pump.

Further, a first heat exchanger for exchanging heat between the first cooling medium and the heat recovery medium is disposed as a heat recovery section using the first cooling medium, and heat recovery is performed via the first heat exchanger. And the first cooling medium as cooling water, hot water obtained by heating through the first refrigerant flow path of the engine body cooling system and the third refrigerant flow path of the air supply cooling system or There is a method in which steam is directly supplied to a hot water consuming area as the heat recovery section.

Similarly, the heat radiating portion of the second cooling medium is also provided with a second heat exchanger for exchanging heat between the second cooling medium and the cooling water and cooling the same, and the temperature is raised by this heat exchange. There is a system using a cooling tower that radiates heat from the cooling water, or a system in which the second cooling medium is used as cooling water and is supplied directly to the cooling tower to radiate heat, and any system may be used.

Further, a third cooling medium independent of the first cooling medium of the engine body cooling system is supplied to the high-temperature side heat exchange section of the air supply cooler in the same manner as described above. It is also possible to perform heat recovery, and depending on the output scale of the engine, only cooling may be performed and heat recovery may be omitted. Further, the supply air in the pressurized state may be either a mixed fluid in which a mixture of fuel and air is pressurized or compressed air.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An engine cooling system according to the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram showing a typical configuration of an engine cooling system according to the present invention. The main components are an engine 1, a generator 2 directly connected to the engine 1, and a cooling medium for cooling a first cooling medium. A first heat exchanger 3 for recovering heat by heating, a second heat exchanger 7 for cooling a second cooling medium, and a pressurized high-temperature mixed fluid of fuel and air supplied to the engine. The point of having a supply air cooler 4 for cooling and a cooling tower 8 for cooling the second cooling medium in the second heat exchanger 7 to cool the circulating water whose temperature has been raised is the same as that of FIG. It is the same as the one.

In the present invention, the supply air cooler 4 is
A high temperature side heat exchange section 4B on the inlet side of the high temperature mixed fluid,
A third refrigerant flow path 4b formed in the high-temperature side heat exchange section 4B is divided into two heat exchange sections with the low-temperature side heat exchange section 4A on the outlet side (supply side to the engine) of the mixed fluid. It is different from the system of FIG. 5 described above in that it is connected to a first refrigerant flow path 1a formed in a required cooling section of the engine body by a pipe L12.

That is, in the present invention, the first refrigerant flow path 1a of the engine body cooling system and the third refrigerant flow path 4 of the air supply cooling system are provided.
b, the first cooling medium, which is a heat recovery refrigerant, is supplied to both flow paths, and in the first refrigerant flow path 1a, heat exchange is performed with a required cooling portion of the engine main body, thereby causing The required cooling portion is cooled and heated, while the third refrigerant flow path 4b is cooled and heated by exchanging heat with the high-temperature mixed fluid, and is heated via both of the flow paths 1a and 4b. The first cooling medium is supplied to the primary side flow path 3a of the first heat exchanger 3 and exchanges heat with the water to be heated, which is supplied to the secondary side, to heat the water to be treated. It is configured to be hot water.

Accordingly, in the first heat exchanger 3 for waste heat recovery, both waste heat from the engine body and waste heat of the high-temperature mixed fluid are recovered, so that the heat recovery efficiency is improved. Will be fulfilled.

Next, an embodiment of the present invention will be described with reference to the flow chart of FIG. In the following description, an example in which cooling water is used for both the first cooling medium and the second cooling medium will be described. However, the present invention is not limited to this, and other cooling media, such as brine, etc. It goes without saying that any commonly used cooling medium can be used.

First, the primary side flow path 3a of the first heat exchanger 3
The first cooling water cooled to about 85 ° C. by the heated water supplied from the pipe L4 to the secondary flow path 3b is connected to the pipe L1.
The required part of the engine main body is cooled while flowing through the first refrigerant flow path 1a formed in the required cooling part in the engine 1 main body. Supplied to the cooler 4, where the heat exchanges with the mixed fluid of about 170 ° C. and high temperature and high pressure supplied from the pipe G2 while flowing through the second refrigerant flow path 4b of the high temperature side heat exchange section 4B. While cooling it to about 90 ° C,
It is heated to 6 ° C. and returned to the first heat exchanger 3 via the pipe L13 and the pump P1. The first heat exchanger 3 exchanges heat with the heated water supplied from the pipe L4 to the secondary flow path 3b, and converts this into hot water of about 80 ° C.
From a hot water tank (not shown) to a consumption area (hotel, hospital, heated pool, etc.).

The first cooling water circulation pump P1 is disposed in the inlet pipes L2 and L3 of the first heat exchanger 3 in the illustrated example, but is connected to the outlet pipe L1 on the low temperature side. It goes without saying that they may be arranged.

On the other hand, the primary side flow path 7a of the second heat exchanger 7
The second cooling water cooled to about 35 ° C. by exchanging heat with the cooling water supplied from the pipe L10 to the secondary flow path 7b is:
It is supplied to the air supply heat exchanger 4 via a pipe L6, a pump P2, and a pipe L7, and is supplied from the pipe G2 while flowing through the third refrigerant flow path 4a of the low-temperature side heat exchange section 4A. The heat exchange unit 4B exchanges heat with the first cooling water to obtain 90
It exchanges heat with the mixed fluid cooled to about 40 ° C., cools it to about 40 ° C., and raises itself to about 40 ° C. and returns to the second heat exchanger 7 via the pipe L8.

The cooling water whose temperature has been raised by cooling the second cooling water in the second heat exchanger 7 is supplied to a cooling tower 8 through a pipe L11, where the heat absorbed by the second cooling water is converted into air. And supplied to the second heat exchanger 7 via the pipe L9, the pump P3 and the pipe L10.

In the illustrated example, the circulation pump P2 for the second cooling water is disposed on the outlet pipes L6 and L7 of the second heat exchanger 7, but is disposed on the inlet pipe L8. Needless to say, it is good. Similarly, the cooling water circulation pump P3
Also in the example shown in the figure, it is arranged on the outlet side pipe of the cooling tower 8, but it goes without saying that it may be arranged on the inlet side pipe L11 side.

In the above example, the temperature of each part of the cooling water is an example for facilitating the understanding of the present invention, and is based on the environmental conditions such as the flow rate of the cooling water and seasonal factors, and the engine. It should be noted that the value greatly varies depending on the type of waste heat and the amount of waste heat recovered.

FIG. 2 is a conceptual diagram showing the structure of the air supply cooler 4. The cooler 4 is divided into a high temperature heat exchange section 4B on the right side and a low temperature The pressurized, high-temperature mixed fluid is partitioned from the heat exchange section 4A and flows from the inlet flow path G2 to the outlet flow path G3 so as to penetrate both heat exchange sections. Heat exchange section 4
In B, the third refrigerant flow path 4b flows in from the pipe L12.
The heat exchange with the first cooling water flowing out of the pipe L13 through the pipe L13, and then, in the low-temperature heat exchange section 4A, the second cooling water flowing from the pipe L7 and flowing out of the pipe L8 through the second refrigerant flow path 4a. It is designed to exchange heat with. This heat exchanger 4
Any type may be used, but in general, a fin tube type heat exchanger which has a large heat transfer area per unit volume and is easily miniaturized is preferable. It is needless to say that the structure of the supply air cooler 4 may be such that the high-temperature side heat exchange section and the low-temperature side heat exchange section are formed by independent heat exchangers in addition to the above-mentioned integrated type. .

Next, the total energy efficiency in the above embodiment of the present invention will be described with reference to FIG. 3, which is a conceptual diagram similar to that shown in FIG.
When 0 is set, the energy recovered from the generator as electric power is about 36%, and the energy released out of the system as exhaust gas from the pipe G5 is about 30%, as in FIG. The energy released from the cooling tower 8 to the atmosphere is about 3%, which is 2% lower than the conventional one.
5, the energy recovered as hot water increased by 31% and 2%, and as a result, the total energy efficiency recovered as electric power and hot water increased by about 67% and 2%. In this case, an example in which the waste heat is not recovered from the pipe G5 is shown. However, when the heat is recovered from the exhaust gas, the energy efficiency is further improved. Absent.

Since the temperature of the required cooling section of the engine body cooling system is as high as several hundred degrees and the temperature of the pressurized mixed fluid is as high as about 170 ° C., the first refrigerant flow path 1a The flow order of the third refrigerant flow path 4b of the air supply and cooling system is such that the first refrigerant flow path 1a flows through the first refrigerant flow path 1a, and then is supplied to the third refrigerant flow path 4b via the pipe L12 and further heated as described above. In addition, conversely, first, the first cooling medium supplied from the pipe L13 to the third refrigerant flow path 4b and heated is supplied to the first refrigerant flow path 1a via the pipe L12 to further heat the same. , Whichever comes first.

The temperature of the other side of the first refrigerant flow path 1a and the third refrigerant flow path 4b through which the first cooling water flows is 1
Since the temperature is as high as 00 ° C. or higher, a boiling heat transfer method can be employed in a portion where the first cooling water exchanges heat in a later step. For example, in the example shown in FIG. 1, first, the first cooling water heated to about 94 ° C. in the first refrigerant flow path 1a flows into the third refrigerant flow path 4b, where the temperature of the first cooling water is raised to 100 ° C. or higher. Heating and boiling, and supplying the boiling superheated steam or the gas-liquid mixed fluid of steam and water to the first heat exchanger 3 to condense water in the primary side flow path and perform the above-described heat recovery It is also possible to do.

In this case, the first cooling water naturally circulates due to the pressure change caused by the vaporization of water in the air supply heat exchanger 4 and the condensation of steam in the first heat exchanger 3. It is also possible to omit the pump P1 in the first cooling water circulation system to further save energy. When the first cooling water is first supplied to the third refrigerant channel 4b and heated and then supplied to the first refrigerant channel 1a, the first cooling water is supplied through the first refrigerant channel 1a. Needless to say, it may be boiled.

Further, in the above description, an example has been shown in which the heat is exchanged with the mixed fluid of the pressurized fuel and the air in the supply air heat exchanger 4. Only the combustion air may be pressurized, and the fuel may be separately pressurized and injected into the engine. In this case, in the air supply heat exchanger 4, the pressurized high-temperature air and the first cooling medium and Heat exchange will occur with the second cooling medium.

In the example shown in the figure, a method of exchanging heat between the first cooling medium heated by the first heat exchanger 3 and the water to be heated, that is, the first heat exchanger 3 is used as a heat recovery heat exchanger However, the first heat exchanger 3 can be omitted. In this case, the cooling water to be heated flows through the first refrigerant flow path 1a and the third refrigerant flow path 4b and is heated to a predetermined temperature, and the obtained hot water or steam is directly sent to the consumption area. In any case, the heat recovery method does not change, so that the method may be appropriately selected according to the installation conditions of the plant.

Similarly, in the illustrated example, heat is exchanged between the second cooling medium heated by the second heat exchanger 7 and the cooling water, and the cooling water is radiated by the cooling tower 8. In this case, the second heat exchanger 7 can be omitted. In this case, the second cooling medium is used as cooling water, and the cooling water heated by the air supply cooler 4 is directly supplied to the cooling tower 8. A reduction effect is expected.

Next, FIG. 4 is a flow sheet showing another embodiment of the present invention. The difference from FIG. 1 is that the high temperature side heat exchange section 4B of the air supply cooler 4 has the engine body cooling. A third cooling medium independent of the first cooling medium, which is a system refrigerant, is supplied, and a third heat exchanger 9 is newly disposed. The other points are the same as those in FIG. 1, and thus the same reference numerals are given and the detailed description is omitted.

That is, in FIG. 4, a first cooling medium is circulated through the first cooling medium flow path 1a in the engine body 1 to cool a required cooling portion of the engine. The heat is supplied to the first heat exchanger 3 and recovered. Therefore, the first cooling medium is circulated between the inside of the engine body 1 and the first heat exchanger 3. On the other hand, the third refrigerant flow path 4 of the high temperature side heat exchange section 4B of the supply air cooler 4
b, a third cooling medium is supplied from the pipe L14, where it is heated by exchanging heat with the high-temperature supply air supplied from the pipe G2, and is passed through the pipe L15, the pump P4, and the pipe L16. It is supplied to the primary flow path 9a of the exchanger 9. The heat exchanger 9 exchanges heat with the heated water supplied to the secondary flow path 9b via the pipe L18, is cooled to a predetermined temperature, and is again cooled from the pipe L14 to the high-temperature heat exchange of the air supply cooler 4 from the pipe L14. Part 4
B. That is, the third cooling medium circulates between the third heat exchanger 9 and the high-temperature side heat exchange section 4B of the air supply cooler 4.

The heated water whose temperature has been raised by recovering heat in the third heat exchanger 9 becomes heated water of a predetermined temperature, and is supplied from a pipe L17 to a predetermined consuming area for use. In this case, the first heat exchanger 3 does not generate high-temperature hot water,
The third heat exchanger 9 supplies two types of water according to the intended use by changing the temperature of the heated water recovered by the two heat exchangers 3 and 9 such as generating medium-temperature hot water. Becomes possible. Needless to say, it is also possible to generate hot water having substantially the same temperature in both heat exchangers 3 and 9 and supply the hot water to the same hot water tank.

In the above description, the first cooling medium to the third cooling medium are used to cool the engine body and the high-temperature side heat exchange section of the supply air cooler, and then recover the heat respectively. Is applicable to engine cooling regardless of the form and presence of heat recovery.Although an engine for driving a generator is described as an example, the present invention is not limited to this. It is needless to say that the present invention can be used as a cooling system for an engine that requires cooling for driving a compressor that generates a large amount of compressed air, a large pump that discharges a large amount of fluid, and the like.

[0041]

As described above, according to the present invention, in an engine cooling system having a waste heat recovery system, conventionally, all the heat recovered by the charge air cooler 4 is discharged from the cooling tower 8 to the atmosphere. However, according to the present invention, the amount of heat recovered by the first cooling medium in the supply air cooler 4 is recovered in a heat recovery unit such as the first heat exchanger 3 which is a heat recovery heat exchanger. As a result, 40% of the amount of heat released from the conventional cooling tower 8 can be effectively used, and not only improvement in energy efficiency but also a great contribution to global environmental problems is expected.

In particular, when the supercharger 5 of the air supply system is driven by the exhaust gas turbine 6, the energy possessed by the exhaust gas is recovered through the exhaust gas turbine 6 and applied to the air supply. Conventionally, in a charge air cooler, the heat energy recovered from the charge air was released in a cooling tower.
According to the present invention, the heat can be recovered by the heat recovery unit. Also, when the supercharger is driven by the engine output, this driving energy can be recovered from the supply air cooler.

If the first cooling medium is formed as cooling water and the cooling water is boiled in the heat recovery step, the cooling water circulation pump can be omitted due to boiling and condensation in the heat recovery system. It is expected that more energy saving effect will be obtained.

In order to supply the first cooling water (first cooling medium) heated between the heat exchangers directly to the consuming area, the first heat exchanger 3 for heat recovery and the circulation Since the pump P1 can be omitted, a further energy saving effect and a reduction in equipment cost are expected.

Further, if the second cooling water (second cooling medium) is heated in the low-temperature side heat exchange section 4A of the supply air cooler 4 and then directly supplied to the cooling tower 8, Since the second heat exchanger 7 and the circulating pump P2 can also be omitted, cost reduction of equipment and further energy saving effects are expected.

Further, the first cooling water (first cooling medium) for cooling the engine body for heat recovery and the third cooling water (third cooling medium) to be supplied to the high-temperature side heat exchange section of the charge air cooler. By forming the independent heat recovery sections, it is possible to obtain heated water at different temperatures, so that it is expected that hot water or hot water can be easily adjusted according to the application.

Also, since heat is recovered from the high-temperature side heat exchange section of the supply air cooling system, only the cooling water heated through the low-temperature side heat exchange section of the supply air heat exchange system is heated. Heat is radiated into the atmosphere by the cooling tower, and as a result, compared with the conventional cooling tower that radiates heat from the cooling water heated in both the high-temperature heat exchange section and the low-temperature heat exchange section. This makes it possible to reduce the size of the cooling tower, thereby improving energy efficiency and further reducing equipment costs.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing one embodiment of an engine cooling system according to the present invention.

FIG. 2 is a schematic view showing one example of an air supply cooler used in the present invention.

FIG. 3 is a conceptual diagram showing energy efficiency in the engine cooling system of the present invention.

FIG. 4 is a flow sheet showing another embodiment of the engine cooling system according to the present invention.

FIG. 5 is a flow sheet showing a conventional engine cooling system.

FIG. 6 is a conceptual diagram showing energy efficiency in a conventional engine cooling system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 1a 1st refrigerant flow path 2 Generator 3 1st heat exchanger 4 Supply air cooler 4A Low temperature side heat exchange part 4B High temperature side heat exchange part 4a 2nd refrigerant flow path 4b 3rd refrigerant flow path 5 Supercharger 6 Exhaust gas turbine 7 Second heat exchanger 8 Cooling tower 9 Third heat exchanger

Claims (16)

[Claims] An engine having an engine body cooling system for cooling a required cooling portion of a body of the engine, and an air supply cooling system for cooling pressurized air to be supplied to the engine. In the cooling system, the air supply cooler (4) arranged in the air supply cooling system includes two heat exchange units, a low-temperature side heat exchange unit (4A) and a high-temperature side heat exchange unit (4B), Heat recovery is performed from both the cooling medium flowing through the engine body cooling system and the cooling medium flowing through the high-temperature side heat exchange section (4B) of the charge air cooler (4). Engine cooling system. 2. An engine main body cooling system for flowing a first cooling medium through a required cooling portion of a main body of the engine (1) to cool the required cooling portion, and a pressurized state to be supplied to the engine (1). An engine cooling system having an air supply cooling system for cooling air supply, wherein the engine main body cooling system is a first cooling medium flow path formed in a required cooling portion in the engine (1) and serving as a flow path for the first cooling medium. A cooling medium passage (1a), a heat recovery unit (3) for recovering heat from the first cooling medium, and the supply air cooling system includes a second cooling medium flow path (4a) through which a second cooling medium flows. ), And a high-temperature side heat exchange section (4B) having a third refrigerant flow path (4b) through which the first cooling medium flows. Supply air cooler (4) and the low-temperature side heat exchange section (4A)
And a heat radiating portion (7, 8) for cooling the second cooling medium, which has flowed through the second refrigerant flow path (4a) and has been heated to a predetermined temperature, to thereby maintain the pressurized state. Is cooled by two cooling mediums, the first cooling medium and the second cooling medium. The first refrigerant flow path (1a) of the engine body cooling system and the air supply cooler (4) are cooled. ) Is connected to the third refrigerant flow path (4b) formed in the high-temperature side heat exchange section (4B), whereby the first cooling medium flows through the third refrigerant flow path (4b). The engine cooling system according to claim 1, wherein heat is recovered from both the engine body and the air supply by the first cooling medium. 3. The first cooling medium cools a required cooling portion of the engine main body through a first refrigerant flow path (1a) of the engine main body cooling system, and subsequently, the charge air cooler (4).
3. After cooling the air supply through the third refrigerant flow path (4 b) formed in the high temperature side heat exchange section (4 B), the air supply is supplied to the heat recovery section (3). 4. The described engine cooling system. 4. The pressurized supply of the first cooling medium through the third refrigerant flow path (4b) formed in a high-temperature side heat exchange section (4B) of the charge air cooler (4). After cooling a required cooling portion of the engine main body through the first refrigerant flow path (1a) of the engine main body cooling system, and then supplying the cooled heat to the heat recovery portion (3). Item 3. An engine cooling system according to Item 2. 5. An engine body cooling system for flowing a first cooling medium through a required cooling section of a body of the engine (1) to cool the required cooling section, and a pressurized state to be supplied to the engine (1). An engine cooling system having an air supply cooling system for cooling air supply, wherein the engine main body cooling system is a first cooling medium flow path formed in a required cooling section in the engine (1). A cooling medium passage (1a), a heat recovery unit (3) for recovering heat from the first cooling medium, and the supply air cooling system includes a second cooling medium flow path (4a) through which a second cooling medium flows. ) And a high-temperature side heat exchange section (4B) having a third refrigerant flow path (4b) through which a third cooling medium flows. An air cooler (4) and the second refrigerant flow path (4) in the low-temperature side heat exchange section (4A). ) In the heat radiation unit for cooling the second cooling medium heating and distributed to the predetermined temperature (7,8)
And a heat recovery unit (9) that circulates through the third refrigerant flow path (4b) in the high-temperature side heat exchange unit (4B) and raises the temperature to recover heat from the third cooling medium. The engine cooling system according to claim 1, wherein heat is recovered from both the engine body and the air supply. 6. The first cooling medium is cooling water, and heat generated by the pressurized supply air in the third refrigerant flow path (4b) formed in the high-temperature side heat exchange section (4B). 4. The engine cooling system according to claim 3, wherein the cooling water is boiled during the replacement process. 7. The first cooling medium is cooling water, and in a heat exchange process with a required cooling portion of the engine main body in the first refrigerant flow path (1a) of the engine main body cooling system, the cooling water is cooled. 5. The engine cooling system according to claim 4, wherein the engine is boiled. 8. The third cooling medium is cooling water, and heat generated from the pressurized supply air in the third refrigerant flow path (4b) formed in the high temperature side heat exchange section (4B). The engine cooling system according to claim 5, wherein the cooling water is boiled during the replacement process. 9. The heat recovery section using the first cooling medium includes a first heat exchanger (3) for exchanging heat between the first cooling medium and the heat recovery medium. An engine cooling system according to any one of the above. 10. The first heat exchanger (3) is a waste heat recovery heat exchanger that recovers heat from the first cooling medium, and is provided in a primary flow path (3a) of the heat exchanger. Is to allow the heated first cooling medium to flow, and to flow the heated water as a heat recovery medium through the secondary side flow path (3b) of the heat exchanger to recover this as hot water. The engine cooling system according to claim 9. 11. The first cooling medium is cooling water, and hot water or steam obtained by the heat exchange is directly supplied to hot water or steam consuming area as the heat recovery unit. The engine cooling system according to any one of claims 2 to 10, comprising: 12. The radiator of the second cooling medium, which has been heated by the supply air cooler (4), circulates the heated second cooling medium through the primary flow path (7a) to allow the secondary cooling medium to flow therethrough. The path (7b) has a second heat exchanger (7) through which cooling water flows, and a cooling tower (8) that exchanges heat with the second cooling medium and cools the heated cooling water. An engine cooling system according to any one of claims 2 to 11. 13. An engine body cooling system for flowing a first cooling medium through a required cooling section of a body of the engine (1) to cool the required cooling section, and a pressurized state to be supplied to the engine (1). An engine cooling system having an air supply cooling system for cooling air supply, wherein the engine main body cooling system is a first cooling medium flow path formed in a required cooling portion in the engine (1) and serving as a flow path for the first cooling medium. A coolant passage (1a), and a radiator (3) for cooling the first cooling medium to a predetermined temperature, wherein the air supply cooling system includes a second coolant passage (4a) through which a second cooling medium flows. ) And a high-temperature side heat exchange section (4A) having a third refrigerant flow path (4b) through which the first cooling medium flows.
B), and the temperature rises by flowing through the supply air cooler (4) composed of two heat exchange units and the second refrigerant flow path (4a) in the low temperature side heat exchange unit (4A). A heat radiating portion (7, 8) for cooling the second cooling medium to a predetermined temperature, wherein the first cooling medium passage (1a) of the engine main body cooling system and the air supply cooler (4) The third refrigerant flow path (4b) formed in the high-temperature side heat exchange section (4B) is connected, whereby both the engine body and the air supply are cooled by the first cooling medium. Engine cooling system characterized by things. 14. An engine main body cooling system for flowing a first cooling medium through a required cooling portion of the main body of the engine (1) to cool the required cooling portion, and a pressurized state to be supplied to the engine (1). An engine cooling system having an air supply cooling system for cooling air supply, wherein the engine main body cooling system is a first cooling medium flow path formed in a required cooling section in the engine (1). A coolant passage (1a), and a radiator (3) for cooling the first cooling medium to a predetermined temperature, wherein the air supply cooling system includes a second coolant passage (4a) through which the second cooling medium flows. ) And a high-temperature side heat exchange section (4B) having a third refrigerant flow path (4b) through which a third cooling medium flows. An air cooler (4) and the second refrigerant flow path in the low-temperature side heat exchange section (4A) Heat radiating portion for cooling the second cooling medium temperature was raised by circulating in 4a) to a predetermined temperature (7,8)
And a heat radiating part (9) for flowing through the third refrigerant flow path (4b) in the high temperature side heat exchange part (4B) and increasing the temperature to cool the third cooling medium to a predetermined temperature. An engine cooling system comprising: a cooling unit configured to independently cool both the engine body and the air supply. 15. The engine cooling system according to claim 1, wherein the supply air in the pressurized state is any one of a mixed gas in which a mixture of fuel and air is pressurized or compressed air. 16. The air supply cooler (4) wherein a high-temperature side heat exchange section (4B) and a low-temperature side heat exchange section (4A) are integrally formed. An engine cooling system according to any one of the above.