WO2018110894A1 - Warmup system using recovery of waste heat of construction machine - Google Patents

Abstract

According to the present invention, a warmup system using the recovery of waste heat of a construction machine comprises: an organic Rankine cycle for circulating, in the construction machine having a hydraulic system, a cooling system, and an engine, operating fluid so as to allow the same to successively exchange heat with waste heat or waste energy of the hydraulic system, the cooling system, and the engine; and a turbine to which the operating fluid having circulated through the organic Rankine cycle flows so as to generate mechanical energy for driving the construction machine, wherein if the operating fluid successively exchanging heat with the waste heat or waste energy in operating oil of the hydraulic system, cooling water of the cooling system, and exhaust gas of the engine is not completely evaporated, the operating fluid does not flow toward the turbine and can flow toward the hydraulic system or the cooling system.

Description

Warm-up System Using Waste Heat Recovery of Construction Machinery

The present invention relates to a warm-up system that uses energy, such as waste heat discarded from a construction machine, as a power for warming up a construction machine, and more specifically, from hydraulic oil, cooling water or waste gas of a construction machine having a hydraulic system. The present invention relates to a warm-up system using waste heat recovery of construction machinery that can be used as a power for recovering discarded thermal energy and reusing it as electric power or power.

In the case of a vehicle such as a construction machine using a diesel engine, a lot of heat is generated during operation, and a lot of waste heat is generated in addition to heat energy that is reduced to mechanical energy for driving the vehicle. In this case, except for the thermal energy that is reduced to mechanical energy, the remaining thermal energy is generally discarded.

Accordingly, in recent years, the research and development of the technology to recover the waste energy (waste energy) that is discarded from the exhaust gas, operating oil, cooling water, etc. generated from the engine of the construction machine and recycle into electrical energy or mechanical energy.

The main reason for the interest in this waste energy recovery technology is that there is still a lot of energy discarded even in a high efficiency engine, and the development of combustion and engine peripherals for improving fuel efficiency of diesel vehicles has reached a certain limit. Because. For reference, although the temperature of the working oil is low in the construction machine equipped with a hydraulic system, but contains a lot of heat, the situation is not properly utilized.

Recently, as a method of recovering low-temperature heat energy discharged from exhaust gas of a diesel engine of a construction machine, many power generation apparatuses using an organic rankine cycle (ORC) have been tried. A typical Rankine cycle is a fluidized vapor passing through an evaporator that converts the axial force generated by rotating the turbine into electrical energy, while an organic Rankine cycle does not use water (H ₂ O) as an operating fluid. Organic mixtures such as ammonia (NH ₃ ) and alcohol (C ₂ H ₅ OH) are used which have a lower temperature than water.

Using the organic Rankine cycle as described above, major industrialized countries and manufacturers are actively developing technologies, but utilizing waste energy such as engine exhaust gas or cooling water is not high in heat, and generates less heat. There is a problem that the power can not be large.

On the other hand, in order to recover the thermal energy of the hydraulic oil, cooling water and the exhaust gas of the engine using the organic Rankine cycle in the construction machine having a hydraulic system, the operating oil, cooling water and the engine must be at an appropriate temperature. In general, in order to operate the organic Rankine cycle normally in construction machinery, the working oil should be about 70 ℃ and the coolant should be about 80 ℃, but during the initial cold start of construction machinery, the working oil is only about 20 ℃ and the cooling water is about 50 ℃. Will not. Accordingly, it normally takes about 30 minutes to 1 hour based on the loading operation to normally operate the organic Rankine cycle of recovering thermal energy through the heat exchange between the working oil, the coolant, and the engine and the working fluid of the construction machine. Since working with non-preheated working oil requires more energy of the engine, there is a problem that the fuel efficiency is poor and the efficiency of the work is lowered.

Therefore, the present applicant, the present invention has been proposed to solve the above problems, as related prior art documents, Korean Utility Model Publication No. 20-1996-068288 (name of the invention: heat exchange device for engine warm-up) , Published date: 07/07/1998).

An object of the present invention is to recover the heat energy that is discarded from the operating oil, cooling water or exhaust gas of the engine having a hydraulic system to recycle the power or power to drive the construction machine, and at the same time using waste heat It is to provide a warm-up system using the waste heat recovery of construction machinery that can reduce the warm-up time of construction machinery and reduce the energy required for the warm-up of construction machinery.

The problem to be solved by the present invention is not limited to the above-mentioned problem, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

The above object is, according to the present invention, in a construction machine having a hydraulic system, a cooling system and an engine, circulating a working fluid to heat exchange with the waste heat or waste energy of the hydraulic system, the cooling system and the engine in turn. Organic Rankine cycles; And a turbine for introducing a working fluid circulating through the organic Rankine cycle to generate mechanical energy for driving the construction machine. The hydraulic fluid of the hydraulic system, the cooling water of the cooling system and the waste heat or waste energy of the exhaust gas of the engine are not circulated toward the turbine when the working fluid which is heat-exchanged in turn is not circulated to the hydraulic system. It can be achieved by a warm-up system using the waste heat recovery of the incoming construction machinery.

The working fluid introduced into the hydraulic system may be heat exchanged with the working oil and the cooling water to increase the temperature of the working oil and the cooling water.

The temperature of the working fluid introduced into the hydraulic system may be higher than the temperature of the working oil and the cooling water.

The organic Rankine cycle may include a first heat exchanger configured to heat exchange the working fluid and the working oil; A second heat exchanger configured to heat exchange the working fluid from the first heat exchanger with the cooling water; A third heat exchanger configured to exchange heat between the working fluid from the second heat exchanger and the combustion gas of the engine; A condenser to condense and liquefy the working fluid from the turbine; A storage tank for storing the working fluid from the condenser; And a pump for sending the working fluid stored in the storage tank to the first heat exchanger.

The pump may use the hydraulic oil pressure of the hydraulic system as a drive source.

A first regeneration heat exchanger may be provided between the turbine and the condenser to heat exchange the working fluid from the turbine and the working fluid discharged from the pump.

A second regenerative heat exchanger may be provided between the turbine and the first regenerative heat exchanger to heat exchange the working fluid from the turbine and the working fluid from the second heat exchanger.

And a fourth heat exchanger provided between the third heat exchanger and the turbine to heat-exchange the working fluid from the third heat exchanger and the gas discharged from the exhaust gas recirculation system (EGR) to superheat the working fluid. have.

When the working fluid from the third heat exchanger or the fourth heat exchanger is not completely vaporized, it may be bypassed toward the first heat exchanger without being introduced into the turbine.

A sensor for sensing the temperature, volume, pressure, or heat amount of the working fluid from the third heat exchanger, the fourth heat exchanger, and the turbine; And a bypass provided at a position adjacent to the sensing sensor to bypass the first heat exchanger, the turbine, the first regeneration heat exchanger, or the second regeneration heat exchanger according to the temperature, volume, pressure, or heat quantity of the working fluid. The valve may further include.

The warm-up system using the waste heat recovery of the construction machine of the present invention is utilized as a driving source for driving the construction machine by recovering the heat energy discarded from the operating oil, cooling water and exhaust gas of the engine of the construction machine equipped with a hydraulic system, At the same time, it is possible to shorten the warm-up time of construction machinery and to reduce the energy required for warm-up of construction machinery by using the heat energy that is discarded, thereby improving the fuel efficiency of construction machinery.

In addition, the warm-up system using the waste heat recovery of the construction machine of the present invention, by reducing the time to reach the catalyst activation temperature for exhaust gas purification of the engine through the rapid warm-up of the engine during the initial cold start of the construction machine to reduce harmful exhaust gas and fine dust can do.

1 to 4 is a block diagram showing a warm-up system using the waste heat recovery of the construction machine according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

It is noted that the figures are schematic and not drawn to scale. The relative dimensions and ratios of the parts in the figures have been exaggerated or reduced in size for clarity and convenience in the figures and any dimensions are merely exemplary and not limiting. And the same reference numerals are used to refer to similar features in the same structure, element or part shown in more than one figure.

Embodiments of the present invention specifically illustrate ideal embodiments of the present invention. As a result, various modifications of the drawings are expected. Thus, the embodiment is not limited to the specific form of the illustrated region, but includes, for example, modification of the form by manufacture.

Hereinafter, a warm-up system (hereinafter, referred to as a 'warm-up system') using waste heat recovery of a construction machine according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 to 4 is a block diagram showing a warm-up system 100 according to an embodiment of the present invention.

Warm-up system 100 according to an embodiment of the present invention to be described below is a system mounted on a construction machine. In general, construction machinery includes a lower traveling body having a traveling device driven by a traveling hydraulic motor, a swinging device driven by a turning hydraulic motor, an upper swinging body disposed on the lower traveling body through a turning device, and an upper swinging device. It can be provided with the work machine which is mounted in the center position of the front part of a sieve, and the cab installed in the left position of the front part of an upper turning body.

Here, the work machine may include a boom slidably connected to the upper pivot body, an arm slidably connected to the boom, and a bucket slidably connected to the arm. The work machine may also have a boom cylinder, arm cylinder and bucket cylinder for operating the boom, arm and bucket respectively.

In addition, the construction machine as described above is provided with an engine for driving each hydraulic motor, such as a hydraulic motor for driving, a hydraulic motor for turning, it may be provided with a cooling device to cool the engine.

On the other hand, such a construction machine is a hydraulic system including a hydraulic cylinder and a hydraulic motor is formed, the hydraulic system can operate the work machine by the hydraulic pressure of the operating fluid (Operating fluid). In addition, the construction machine is provided with a cooling system for cooling the engine by using the cooling water, the cooling system can cool the engine by circulating the cooling water (radiator) provided on the engine or one side of the engine.

Warm-up system 100 according to an embodiment of the present invention can recover the heat energy generated or discarded in the hydraulic system, cooling system, engine of the construction machine and recycle it as electrical energy or mechanical energy and use it as a driving force of the construction machine. At the same time, it can also be used as an electric power for shortening the warm-up time of construction machinery, thereby improving fuel efficiency of construction machinery.

Specifically, as shown in Figures 1 to 4, the warm-up system 100 according to an embodiment of the present invention is an organic Rankine cycle by heat exchange with the operating oil of the engine 110 of the construction machine, the hydraulic system of the construction machine The first heat exchanger 120 for heating the working fluid of the engine, the second heat exchanger 122 for heating the working fluid passing through the first heat exchanger 120 by heat exchange with the cooling water of the cooling system of the engine 110, the engine The third heat exchanger 124, the first heat exchanger 120, the second heat exchanger 122, and the first heat exchanger that heat the working fluid passed through the second heat exchanger 122 by heat exchange with the gas discharged from the 110. 3 through the heat exchanger 124, the turbine 130 rotated by the vaporized working fluid, the condenser 140 to cool and condense the working fluid passed through the turbine 130, the liquefied operation in the condenser 140 A storage tank 142 in which the fluid is stored and a pump 144 for sending the working fluid of the storage tank 142 to the first heat exchanger 120 It can be included.

For reference, the dotted line illustrated in FIGS. 1 to 4 means a movement path of the working fluid of the organic Rankine cycle.

1 to 4, the engine 110 is a part for driving a construction machine such as an excavator and a wheel loader. Engine 110 is exhaust gas discharged from the exhaust manifold (not shown), that is, waste exhaust gas is sent to a turbocharger (not shown) to be described later located in the supercharger to inject the compressed air into the engine 110 will be described later. The turbine 130 may be operated to increase the combustion efficiency of the engine 110.

In addition, the engine 110 provided in the construction machine drives a hydraulic motor (not shown) of a hydraulic system for driving respective components of the construction machine, and has a cooling system including a cooling water for cooling the engine 110. can do. On the other hand, the radiator 112 is provided on one side of the engine 110, thereby allowing the heat of the engine 110 to be released to the atmosphere by the inflow / outflow of the cooling water for cooling the heat of the engine 110.

Warm-up system 100 according to an embodiment of the present invention is constructed by recovering the heat energy that is discarded from all the construction machinery that work in a hydraulic pressure system using an Organic Rankine Cycle (ORC) It can be converted into power that can drive the machine.

In this case, the organic Rankine cycle (or organic Rankine circuit) may be composed of a storage tank 142, a pump 144 and an evaporator (or a boiler), a turbine 130, a condenser 140, etc. in which the working fluid is stored.

On the other hand, the warm-up system 100 according to an embodiment of the present invention has an organic Rankine cycle for circulating the working fluid that can be heat exchanged with the hydraulic fluid of the hydraulic system, the cooling water of the cooling system, the exhaust gas of the engine and the like in the construction machine It is possible to recycle the generated waste heat, i.e. waste heat energy.

In general, the temperature of the working oil, cooling water, etc. of the construction machine is not high, but has a lot of thermal energy. In other words, it is preferable to use a material having a low vaporization temperature, that is, a relatively low boiling point, because the working fluid must be exchanged with a low temperature working oil, cooling water, or the like. That is, since the working fluid of the organic Rankine cycle uses a working fluid whose boiling point is lower than that of the working oil and the cooling water, waste heat generated in the construction machine can be efficiently recycled.

Here, the working fluid of the organic Rankine cycle has an organic fluid, i.e., an organic compound having a lower breaking point than water, such as ammonia (NH ₃ ), alcohol (C ₂ H ₅ OH), R124A, R245FA or Organic refrigerants and the like can be used.

The working fluid of the organic Rankine cycle may be discharged from the pump 144 to exchange heat with the hydraulic fluid of the hydraulic system first. Accordingly, the hydraulic oil hydraulic pressure of the hydraulic system of the construction machine can be used as a driving source of the pump 144 of the organic Rankine cycle. That is, the hydraulic system of the construction machine may be configured to be connected to the pump 144 of the organic Rankine cycle so that it is not necessary to generate additional energy to circulate the working fluid of the organic Rankine cycle. For reference, the working fluid which is sent out to exchange heat with the hydraulic system by the pump 144 may be stored in the storage tank 142.

On the other hand, the above-described evaporator or boiler of the organic Rankine cycle may be provided as a heat exchanger, the organic Rankine cycle according to an embodiment of the present invention is the first heat exchanger 120, the second heat exchanger 122 and the third heat exchanger. Each of the groups 124.

As described above, the working fluid sent from the storage tank 142 to the hydraulic system by the pump 144 is heat exchanged by the first heat exchanger (120). The first heat exchanger 120 is a heat exchanged portion between the working oil of the hydraulic system introduced to one side and the working fluid of the organic Rankine cycle introduced to the other side. Accordingly, the first heat exchanger 120 is provided at a position adjacent to the hydraulic system of the construction machine, it is more preferably installed on the hydraulic oil flow path of the hydraulic system of the construction machine.

Here, the temperature of the working fluid of the organic Rankine cycle may be lower than the temperature of the working oil flowing into the first heat exchanger 120. Accordingly, in the first heat exchanger 120, the working fluid obtains heat from the working oil, thereby increasing the temperature, and the working oil is deprived of heat to the working fluid, thereby lowering the temperature.

On the other hand, the working fluid obtained the heat of the working oil in the first heat exchanger 120 may flow into the second heat exchanger (122). At this time, the second heat exchanger 122 is a part that is heat exchanged between the cooling water of the cooling system introduced to one side and the working fluid of the organic Rankine cycle introduced to the other side. Accordingly, the second heat exchanger 122 is provided at a position adjacent to the cooling system of the construction machine, it is preferably installed on the cooling water flow path of the cooling system of the construction machine.

Here, the temperature of the working fluid may be lower than the temperature of the cooling water flowing into the second heat exchanger 122. Accordingly, in the second heat exchanger 122, the working fluid gets heat from the cooling water and the temperature is high, and the working fluid is deprived of heat to the working fluid and the temperature is lowered. For reference, it can be said that the temperature of the coolant is higher than the temperature of the working oil of the construction machine and has more thermal energy. Therefore, the temperature of the working fluid passing through the second heat exchanger 122 may be higher than that of the working fluid passing through the first heat exchanger 120.

Although the working fluid is heat exchanged with the working oil and the cooling water through the first heat exchanger 120 and the second heat exchanger 122, the working fluid in the liquid state is not completely vaporized and is still in the liquid state or mixed with the liquid and gas. May be in a state.

Accordingly, the working fluid from the second heat exchanger 122 may flow into the third heat exchanger 124.

In the third heat exchanger 124, the exhaust gas discharged from the engine 110 and the working fluid from the second heat exchanger 122 exchange heat with each other. The third heat exchanger 124 is preferably provided on the flow path through which the exhaust gas of the engine 110 is discharged. At this time, since the temperature of the gas discharged from the engine 110 is higher than the temperature of the working fluid discharged from the third heat exchanger 122, the working fluid is the heat of the exhaust gas of the engine 110 in the third heat exchanger 124. It can absorb heat from energy.

Accordingly, the temperature of the working fluid of the organic Rankine cycle is sequentially heat exchanged with the working oil, the cooling water, and the exhaust gas while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124. Can be high. That is, since the temperature of the working fluid is gradually increased by the heat exchange with the first heat exchanger 120 and the second heat exchanger 122, the operation through the first heat exchanger 120 and the second heat exchanger 122 The fluid may have more advantageous conditions for complete vaporization as it passes through the third heat exchanger 124.

That is, the first heat exchanger 120 heats the working fluid through the heat exchange of the working fluid and the working fluid of the construction machine, the second heat exchanger 122 is the first heat exchange between the cooling water and the working fluid of the construction machine The working fluid passed through the heat exchanger 120 is heated, and the third heat exchanger 124 heats the working fluid passed through the second heat exchanger 122 through heat exchange between the working gas and the exhaust gas discharged from the engine 110. Can be heated.

At this time, the temperature T1, T2, T3 of the working fluid flowing into the first heat exchanger 120, the second heat exchanger 122 and the third heat exchanger 124 may have a sequence T1 <T2 <T3. In other words, the temperature of the working fluid in the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 is the lowest in the first heat exchanger 120 and the third heat exchanger 124. Can mean the highest at. That is, it may mean that the working fluid is changed into a gas state while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 in the first liquid state.

As described above, the working fluid completely vaporized while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 is transferred to the turbine 130 because the kinetic energy of the gas molecules is large. Inflow may rotate the blade (not shown) connected to the rotating shaft (not shown) of the turbine 130. That is, while the turbine 130 passes through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, the pressure energy of the vaporized working fluid may be converted into rotational energy. have. By connecting the rotational energy generated from the rotating shaft of the turbine 130, that is, mechanical energy with the engine 110 of the construction machine, as the power of the engine 110 of the construction machine to improve the efficiency of the engine 110 of the construction machine. Can be.

On the other hand, one side of the rotary shaft of the turbine 130 may be connected to a generator (not shown) for producing electrical energy, one side of the generator may be provided with a capacitor (not shown) for storing the electricity produced by the generator. For reference, the electric energy stored in the capacitor is used to drive the construction machine, thereby improving the fuel efficiency of the construction machine.

* As described above, since the working fluid in the gas state introduced into the turbine 130 rotates the blade of the turbine 130, the temperature of the working fluid may be lowered by the rotation passing through the turbine 130.

In addition, the working fluid after rotating the turbine 130 may exit the turbine 130 and flow into the storage tank 142. At this time, the working fluid from the turbine 130 is not a complete liquid state, but a mixed state of the working fluid in a gaseous state or a liquid state, it may be a state having a certain amount of heat. Accordingly, it may be necessary to convert the working fluid to a complete liquid state before the working fluid from the turbine 130 flows into the storage tank 142. To this end, the organic Rankine cycle according to an embodiment of the present invention may include a condenser 140 between the turbine 130 and the storage tank 142. The condenser 140 may cool or condense the working fluid passed through the turbine 130 to phase convert the working fluid in the gas state into the liquid state. The working fluid, which is cooled and condensed by the condenser 140 and becomes a complete liquid state, is stored in the storage tank 142.

Here, the working fluid in the liquid state stored in the storage tank 146 may be sent to the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 by the pump 144. In other words, the pump 144 delivers the working fluid in the liquid state stored in the storage tank 142 to the first heat exchanger 120, the second heat exchanger 122, or the third heat exchanger 124. Can be circulated. Accordingly, the working fluid of the organic Rankine cycle is continuously heat exchanged with the first heat exchanger 120, the second heat exchanger 122, or the third heat exchanger 124, thereby rotating the turbine 130. It can produce energy to drive construction machinery.

On the other hand, the warm-up system 100 according to an embodiment of the present invention not only produces energy capable of driving the construction machine through heat exchange between the operating energy of the working oil, cooling water and exhaust gas of the construction machine and the working fluid, It can also be used to warm up construction equipment.

Specifically, when the construction machine is in the warm-up state, that is, the initial starting state, the temperatures of the working oil, the cooling water, and the exhaust gas of the engine may not reach a temperature sufficient to exchange heat with the working fluid. In other words, the temperature of the working oil and the cooling water must be higher than the working fluid temperature for the heat exchange of the working oil and cooling water and the working fluid of the construction machine. For example, in order for the working fluid to normally exchange heat with the hydraulic fluid and the cooling water of the construction machine using the organic Rankine cycle, the temperature at which the hydraulic fluid and the cooling water exchange with the working fluid to change the working fluid phase, that is, the temperature of the hydraulic fluid It should be about 70 ℃ and the coolant temperature should be about 80 ℃.

However, since the temperature of the working oil is only 20 ° C. and the temperature of the cooling water is only about 50 ° C. during the initial starting state of the construction machine, it may be difficult to normally exchange heat between the working oil and the cooling water and the working fluid. Accordingly, the working fluid stored in the storage tank 142 is sent to the first heat exchanger 120 by the pump 144, the first heat exchanger 120, the second heat exchanger 122 and the third heat exchanger ( Even though 124 is passed, it does not have sufficient kinetic energy to rotate the turbine 130 because it is not completely vaporized by the coolant and the exhaust gas of the coolant and the engine with low temperature heat.

On the other hand, the temperature of the working fluid passed through the first heat exchanger 120, the second heat exchanger 122 and the third heat exchanger 124 may be higher than the temperature of the working oil and the cooling water in the initial start-up stage of the construction machine. That is, the temperature of the working fluid subjected to heat exchange while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 is the temperature of the working oil and the coolant in the initial start-up stage of the construction machine. Can be higher.

Accordingly, as shown in FIGS. 1 to 3, the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 in the initial start-up stage of the construction machine is condensed ( Instead of sending it to the condensate 140 and storing it in the storage tank 142, the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 is transferred to the turbine 130. The state of the working fluid is determined using the sensing sensor 170 provided at the front end, and the first heat exchanger 120 is provided through the warm-up flow path 160 provided at the front end of the turbine 130 using the bypass valve 180. ) To the side. Accordingly, in the initial start-up phase of the construction machine, the working fluid heat exchanged through the first to third heat exchangers (120, 122, 124) is heat-exchanged with the working oil in the first heat exchanger 120 and the second By exchanging heat with the cooling water in the heat exchanger 122, the temperature of the working oil and the cooling water may be increased rapidly. That is, the warm-up system 100 of the present invention recycles the thermal energy discarded in the construction machine, that is, the organic Rankine cycle for generating driving force for driving the construction machine by recycling the thermal energy discarded from the working oil, cooling water and the exhaust gas of the engine. It can be operated normally within a short time.

To this end, when it is determined that the working fluid that has passed through the third heat exchanger 124 is not completely vaporized as a result of detecting the state of the working fluid from the third heat exchanger 124 by the detection sensor 170, the bypass is bypassed. The flow path toward the turbine 130 is blocked through the valve 180 and only the warm-up flow path 160 flowing toward the first heat exchanger 120 or the second heat exchanger 122 is opened to open the first heat exchanger 120 or The working fluid may be introduced into the second heat exchanger 122.

Meanwhile, referring to FIGS. 2 to 4, the warm-up system 100 according to an embodiment of the present invention may further include a first regeneration heat exchanger 150 or a second regeneration heat exchanger 152.

As shown in FIG. 1, the working fluid passing through the turbine 130 may be directly transferred to the condenser 140, but as shown in FIGS. 2 to 4, the working fluid passing through the turbine 130 may be the first regenerative heat exchanger. It may be introduced into the gas 150 or the second regeneration heat exchanger 152 to recover the remaining thermal energy of the working fluid passed through the turbine 130 to be recycled.

In other words, if the working fluid from the turbine 130 does not completely liquefy to a liquid state and has a certain amount of heat, it may not be suitable to flow into the condenser 140. If the working fluid from the turbine 130 has a certain amount of heat, the condenser 140 needs to be large in order to completely liquefy the working fluid in the condenser 142. It may be difficult to install a large capacity condenser 140, and the first heat exchanger 120, the second heat exchanger 122, or the third heat exchanger (using the heat of the working fluid from the turbine 130) This is because the temperature of the working fluid flowing into the 124 may be increased.

Specifically, referring to FIGS. 2 to 4, the first regeneration heat exchanger 150 may exchange heat between the working fluid passed through the turbine 130 and the working fluid sent from the pump 144. At this time, when the temperature of the working fluid passed through the turbine 130, that is, the working fluid after generating a rotational force to the turbine 130 is higher than the temperature of the working fluid stored in the storage tank 142, the first regeneration heat exchanger 150 By using), the working fluid passed through the turbine 130 and the working fluid sent from the pump 144 can be heat exchanged with each other. The working fluid sent from the pump 144 obtained by heat exchange with the working fluid from the turbine 130 by the first regeneration heat exchanger 150 may be transferred to the first heat exchanger 120. Accordingly, the heat exchange efficiency between the working oil and the working fluid in the first heat exchanger 120 can be further increased.

3 and 4, the second regeneration heat exchanger 152 may exchange heat between the working fluid passed through the turbine 130 and the working fluid from the second heat exchanger 122. When the temperature of the working fluid passing through the turbine 130, that is, the working fluid after the turbine 130 is rotated is higher than the temperature of the working fluid heated in the second heat exchanger 122, the second regeneration heat exchanger 152 By using the heat exchanger and the working fluid passed through the turbine 130 and the second heat exchanger 122 may be exchanged again. The working fluid whose temperature is increased by heat exchange by the second regeneration heat exchanger 152 may be transferred to the third heat exchanger 124.

As described above, the first regenerative heat exchanger 150 and the second regenerative heat exchanger 152 may not only recycle thermal energy contained in the working fluid from the turbine 130, but also flow into the condenser 140. By sufficiently cooling the working fluid before it is possible to completely liquefy the working fluid even with a small capacity condenser 140.

For reference, as described above, the warm-up system 100 according to an embodiment of the present invention is the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 to recycle the working fluid passed through the turbine 130 ), But is not necessarily limited thereto. That is, when it is determined that the temperature of the working fluid after rotating the turbine 130 is low enough to completely liquefy through the condenser 140, both the first regeneration heat exchanger 150 and the second regeneration heat exchanger 152. It may not be prepared.

Furthermore, the temperature T1 'of the working fluid on the first regeneration heat exchanger 150 may have a temperature lower than the temperature T2' of the working fluid on the second regeneration heat exchanger 152. In addition, the temperature of the working fluid on the first regeneration heat exchanger 150 is lower than the temperature of the working fluid on the first heat exchanger 120, the temperature of the working fluid on the second regeneration heat exchanger 152 is a second heat exchanger ( 122) may be higher than the temperature of the working fluid on the bed.

3, when it is detected that the working fluid heat exchanged with the heat energy of the exhaust gas of the engine 110 is not completely vaporized in the third heat exchanger 124, the third heat exchanger 124 may be discharged. The working fluid may be diverted to the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 without sending the working fluid to the turbine 130.

Specifically, the working fluid is in a complete gas state even after passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 by the sensing sensor 170 provided in front of the turbine 130. When it is determined that the phase change is not performed, the working fluid from the third heat exchanger 124 is diverted to the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 through the bypass flow passage 162. Can be. If the working fluid, which was initially in liquid state, enters the turbine 130 without being converted into the complete gas state, the turbine 130 cannot be rotated, and the blade (not shown) of the turbine 130 may be damaged. Because it can.

Therefore, by detecting the state of the working fluid from the third heat exchanger 124 by using the sensor 170, if it is determined that the working fluid passed through the third heat exchanger 124 is not completely vaporized, the bypass valve The flow path toward the turbine 130 is blocked through the 180, and only the flow path flowing toward the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 is opened to open the first regeneration heat exchanger 150 or the second flow path. The working fluid may be introduced into the regeneration heat exchanger 152.

1 to 3, the sensing sensor 170 provided at the front end of the turbine 130 detects the temperature, pressure, or volume of the working fluid from the third heat exchanger 124, and thus the state of the working fluid may be reduced. It can detect whether it is liquid or gas. The state of the working fluid sensed by the sensor 170 may be transmitted to a controller (not shown) for controlling the opening and closing of the bypass valve 180. For reference, the controller may control the opening and closing of the bypass valve 180 to prevent the working fluid which is not completely vaporized from flowing into the turbine 130.

As described above, the detection sensor 170 may be provided as a sensor that can detect the state of the working fluid. In this case, the sensing sensor 170 may be provided as a temperature sensor for sensing the temperature of the working fluid, or provided as a pressure sensor for sensing the phase change of the working fluid, that is, the volume or pressure of the working fluid. It may be, but is not necessarily limited thereto, and may be provided as various types of detection sensors according to physical properties of the working fluid.

On the other hand, referring to Figure 4, the warm-up system 100 according to an embodiment of the present invention may further include a fourth heat exchanger (126).

Specifically, the fourth heat exchanger 126 is to heat exchange the working fluid from the third heat exchanger 124 again after heat exchange with the exhaust gas of the engine 110 in the third heat exchanger 124. In other words, the fourth heat exchanger 126 heat exchanges the gas discharged from the exhaust gas recirculation system (EGR) of the engine 110 and the working fluid from the third heat exchanger 124 with each other. You can. That is, the fourth heat exchanger 126 heats the working fluid from the exhaust gas recirculation system (EGR) of the engine 110 and the working fluid from the third heat exchanger 126, thereby superheating the working fluid. You can. As the working fluid from the third heat exchanger 124 passes through the fourth heat exchanger 126, the working fluid heat-exchanged again may be completely vaporized and phase-converted to a gas state to rotate the turbine 130.

At this time, the temperature T4 of the working fluid on the fourth heat exchanger 126 may be higher than the working fluid temperature T3 in the third heat exchanger 124. If the working fluid is not completely vaporized by the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, the working fluid may be completely vaporized through the fourth heat exchanger 126.

For reference, even though the working fluid heated by the heat exchange with the exhaust gas of the engine 110 in the third heat exchanger 124 is completely vaporized, the working fluid passing through the third heat exchanger 124 remains in the fourth heat exchanger 126. It may be to be introduced into the turbine 130 through.

In other words, even when it is determined that the working fluid in the liquid state is completely phase-converted to the gas state while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, the working fluid is a turbine ( Instead of directly entering 130, the superfluous heating fluid passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 is superheated by the fourth heat exchanger 126. Super Heating) may be configured to enter the turbine 130.

This is because, as the working fluid from the third heat exchanger 124 passes through the fourth heat exchanger 126, the temperature of the working fluid is further increased to rotate the turbine 130, that is, pressure energy or movement of gas molecules. Energy may be increased and consequently may increase the amount of mechanical energy output from turbine 130. In other words, since the energy of the working fluid exiting from the third heat exchanger 124 and passing through the fourth heat exchanger 126 is greater than the energy of the working fluid passing through the third heat exchanger 124, the turbine 130. ) Can be rotated more quickly. Therefore, even when it is determined that the working fluid that has passed through the third heat exchanger 124 is completely converted into a gas state, it is preferable to allow the energy of the working fluid to be increased by allowing the fourth heat exchanger 126 to flow into the fourth heat exchanger 126.

However, if the working fluid in the liquid state is completely phase-converted into the gas state through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, the fourth heat exchanger 126 may be omitted. The warm-up system 100 may be configured. In other words, when it is determined that the working fluid is 100% vaporized even after the third heat exchanger 124, it is preferable to configure the warm-up system 100 according to an embodiment of the present invention without the fourth heat exchanger 126. Do.

In addition, referring to FIG. 4, when it is detected that the working fluid heat exchanged with the exhaust gas of the engine 110 is not completely vaporized in the fourth heat exchanger 126, the first regeneration is performed without passing through the turbine 130. Bypass to the heat exchanger 150 or the second regeneration heat exchanger (152).

Specifically, the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124 and the fourth heat exchanger 126 by the sensing sensor 170 provided at the front end of the turbine 130. If it is determined that the working fluid in the liquid state is not completely converted to the gas state even after passing through the gas, it is to be introduced into the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 through the bypass passage 162. desirable. This is because the working fluid in the liquid state is not completely vaporized even after passing through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126. 130 is difficult to rotate the turbine 130 and may damage the blade (not shown) of the turbine 130. Accordingly, when it is determined by the sensor 170 that the working fluid passing through the fourth heat exchanger 126 is not completely vaporized, the flow path flowing toward the turbine 130 using the bypass valve 180 is blocked, Only the flow path of the working fluid from the fourth heat exchanger 126 toward the first regeneration heat exchanger 150 or the second regeneration heat exchanger 152 may be opened.

For reference, the above-mentioned bypass valve 180 is all for changing the flow path of the working fluid, it may be provided in the form of a general direction switching valve.

On the other hand, as described above, when the organic Rankine cycle is operated in the initial stage of operation of the construction machine, the working fluid is the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124 and the third Even if all of the four heat exchangers 126 are passed, they may not be completely phase-converted to the gas state. At this time, the temperature of the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124 and the fourth heat exchanger 126 is the operating oil in the initial starting state of the construction machine And higher than the temperature of the cooling water.

As shown in FIG. 4, the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126 in the initial startup stage of the construction machine. Instead of sending to the first regeneration heat exchanger 150, the second regeneration heat exchanger 152 or the condenser 140 to determine the state of the working fluid using the sensor 170 provided in the front end of the turbine 130. Thus, the flow path flowing through the bypass valve 180 toward the turbine 130, the first regeneration heat exchanger 150, and the second regeneration heat exchanger 152 is blocked, and the warm-up flow path 160 is opened to open the first heat exchanger ( 120, the working fluid passing through the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126 may be introduced into the first heat exchanger 120. For reference, in FIG. 4, the working fluid passing through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126 is the first heat exchanger 120 only. Although illustrated as being introduced, the working fluid may be introduced into either the first heat exchanger 120 or the second heat exchanger 122.

 Accordingly, the operating fluid of the organic Rankine cycle in the initial start-up phase of the construction machine is heat-exchanged with the hydraulic oil of the hydraulic system of the construction machine, the cooling system of the cooling system can be rapidly increased the temperature of the hydraulic oil and the cooling water. In other words, the warm-up system 100 of the present invention recycles thermal energy discarded in the construction machine, that is, the organic Rankine cycle to generate driving force for driving the construction machine by recycling the thermal energy discarded from the working oil, cooling water and the exhaust gas of the engine. Can be driven normally within a short time.

1 to 4, the operation of the warm-up system 100 according to an embodiment of the present invention will be briefly described.

First, the working fluid stored in the storage tank 142 is sent to the first heat exchanger 120 by the pump 144. At this time, the pump 144 may be operated by the hydraulic oil of the hydraulic system of the construction machine. For reference, the working fluid sent to the first heat exchanger 120 is in a liquid state.

Then, the working fluid in the liquid state sent to the first heat exchanger 120 is heat exchanged with the working oil after being used in the hydraulic system of the construction machine. Here, the use of the heat energy discarded in the working oil of the construction machine is because the heat energy discarded from the construction machine, that is, the lowest temperature among the waste energy, but has a large amount of heat. For reference, the working oil after being heat exchanged with the working fluid may be recovered to a drain tank (not shown) of the construction machine.

Then, the working fluid heat exchanged with the working oil in the first heat exchanger 120 flows into the second heat exchanger 122. The second heat exchanger 122 is heat exchanged with the working fluid passing through the first heat exchanger 120 and the cooling water of the cooling system that cools the heat of the engine 110 of the construction machine. At this time, utilizing the heat energy discarded in the cooling water used to cool the heat of the engine 110 is because it has the next high temperature after the waste heat of the operating oil described above. Meanwhile, the coolant heat exchanged with the working fluid passing through the first heat exchanger 120 in the second heat exchanger 122 may be recovered to the coolant tank of the cooling system of the construction machine.

Then, the working fluid heat exchanged in the second heat exchanger 122 flows into the third heat exchanger 124. The third heat exchanger 124 is heat exchanged with the working fluid passed through the second heat exchanger 122 and the exhaust gas discharged from the engine 110 of the construction machine. At this time, the use of the thermal energy discarded in the exhaust gas of the engine 110 is because it has the next high temperature after the waste heat of the hydraulic oil and the cooling water. Furthermore, since the exhaust gas discharged from the engine 110 has a considerably high temperature, the exhaust gas may be injured by the exhaust gas when the exhaust gas is discharged to the outside. On the other hand, the exhaust gas heat exchanged with the working fluid passed through the second heat exchanger 122 in the third heat exchanger 124 may be discharged to the outside of the construction machine.

Subsequently, the working fluid, which is completely gaseous while passing through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, rotates the turbine 130.

If the construction machine is in an initial starting state, even if the working fluid passes through all of the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124, it does not become a complete gas state. In this case, the temperature of the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 may be higher than the temperature of the working oil and the coolant in the initial starting state of the construction machine. Therefore, the construction machinery by allowing the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, and the third heat exchanger 124 to flow into the first heat exchanger 120 without being sent to the turbine 130. Increase the temperature of the hydraulic oil and coolant in the initial starting state.

In addition, when the temperature of the working fluid after rotating the turbine 130 is high, it is to be introduced to the first regeneration heat exchanger (150). Accordingly, in the first regeneration heat exchanger 150, the working fluid after rotating the turbine 130 and the working fluid sent from the storage tank 142 to the first regeneration heat exchanger 150 may be heat exchanged. Furthermore, when the temperature of the working fluid after the turbine 130 is rotated is high, the working fluid and the second heat exchanger 122 after the turbine 130 are rotated through the second regenerative heat exchanger 152 are passed. The working fluid can be heat exchanged again.

If it is determined that the working fluid that has passed through the third heat exchanger 124 is not completely vaporized, the gas discharged from the exhaust gas recirculation system (EGR) and the working fluid may be exchanged with each other through the fourth heat exchanger 126. .

On the other hand, in the initial starting state of the construction machine, even if the working fluid passes through all of the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124 and the fourth heat exchanger 126, It may not be in a gaseous state. At this time, the temperature of the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126 is the operating oil in the initial starting state of the construction machine and It may be higher than the temperature of the coolant. Thus, the first heat exchanger 120 does not send the working fluid passed through the first heat exchanger 120, the second heat exchanger 122, the third heat exchanger 124, and the fourth heat exchanger 126 to the turbine 130. 120 or the second heat exchanger 122 to increase the temperature of the operating oil and the coolant in the initial starting state of the construction machine.

Then, the working fluid after rotating the turbine 130 is condensed into a liquid through the condenser 140, and then stored in a liquid state in the storage tank 142. At this time, the heat is exchanged again via the first regenerative heat exchanger 150 and the second regenerative heat exchanger 152, instead of directly going to the condenser 140 according to the temperature of the working fluid after the turbine 130 is rotated. After condensation in a liquid state through the condenser 140 may be stored in the storage tank 142.

By the above configuration, the warm-up system 100 using the waste heat recovery of the construction machine according to an embodiment of the present invention recovers thermal energy that is discarded from the exhaust oil of the working oil, the cooling water, and the engine of the construction machine having the hydraulic system. It can be used as a driving source that can drive construction machinery, and at the same time can be used as a power for shortening the warm-up time of construction machinery can improve the fuel economy of construction machinery.

In addition, the warm-up system 100 using the waste heat recovery of the construction machine of the present invention, through the rapid warm-up of the engine during the initial cold start of the construction machine to shorten the time to reach the catalyst activation temperature for purifying the exhaust gas of the engine by harmful exhaust gas and fine Dust can be reduced.

As described above, in one embodiment of the present invention has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention in the above embodiment The present invention is not limited thereto, and various modifications and variations can be made by those skilled in the art to which the present invention pertains. Therefore, the spirit of the present invention should not be limited to the described embodiments, and all of the equivalents and equivalents of the claims, as well as the following claims, will fall within the scope of the present invention. .

The present invention can be used for a warm-up system using waste heat recovery of construction machinery that uses energy such as waste heat discarded in construction machinery and uses it as a power for warming up construction machinery.

Claims (10)

1. In a construction machine having a hydraulic system, a cooling system and an engine,

   An organic Rankine cycle for circulating a working fluid to sequentially heat exchange with waste heat or waste energy of the hydraulic system, the cooling system and the engine; And

   A turbine for introducing a working fluid circulating through the organic Rankine cycle to generate mechanical energy for driving the construction machine;

   Including,

   When the hydraulic fluid of the hydraulic system, the cooling water of the cooling system, and the waste heat or waste energy of the exhaust gas of the engine are not completely vaporized, the hydraulic fluid does not flow into the turbine, but toward the hydraulic system or the cooling system. Warm-up system using waste heat recovery of the construction machine, characterized in that the inflow.
2. The method of claim 1,

   The working fluid introduced into the hydraulic system or the cooling system is heat-exchanged with the working oil and the cooling water to increase the temperature of the working oil and the cooling water.
3. The method of claim 2,

   The warm-up system using the waste heat recovery of the construction machine, characterized in that the temperature of the working fluid introduced into the hydraulic system or the cooling system is higher than the temperature of the hydraulic oil and the cooling water.
4. The method of claim 1,

   The organic Rankine cycle,

   A first heat exchanger for exchanging heat between the working fluid and the working oil;

   A second heat exchanger configured to heat exchange the working fluid from the first heat exchanger with the cooling water;

   A third heat exchanger configured to exchange heat between the working fluid from the second heat exchanger and the combustion gas of the engine;

   A condenser to condense and liquefy the working fluid from the turbine;

   A storage tank for storing the working fluid from the condenser; And

   And a pump for sending the working fluid stored in the storage tank to the first heat exchanger.
5. The method of claim 4, wherein

   The pump is a warm-up system using the waste heat recovery of the construction machine, characterized in that the hydraulic oil of the hydraulic system as a drive source.
6. The method of claim 4, wherein

   And a first regeneration heat exchanger provided between the turbine and the condenser and heat exchanging a working fluid discharged from the turbine and a working fluid discharged from the pump.
7. The method of claim 6,

   And a second regeneration heat exchanger provided between the turbine and the first regeneration heat exchanger, the second regeneration heat exchanger for exchanging a working fluid from the turbine and a working fluid from the second heat exchanger. Warm-up system using.
8. The method of claim 7, wherein

   And a fourth heat exchanger disposed between the third heat exchanger and the turbine and configured to superheat the working fluid by heat-exchanging the gas discharged from the working fluid from the third heat exchanger and the exhaust gas recirculation system (EGR). Warm-up system using waste heat of the construction machine.
9. The method of claim 8,

   When the working fluid from the third heat exchanger or the fourth heat exchanger is not completely vaporized, the working fluid from the third heat exchanger or the fourth heat exchanger does not flow into the turbine and the first heat exchanger or Warm-up system using the waste heat recovery of the construction machine characterized in that it is bypassed toward the second heat exchanger.
10. The method of claim 9,

    A sensor for sensing the temperature, volume, pressure, or amount of heat of the working fluid from the third heat exchanger or the fourth heat exchanger; And

    The first heat exchanger, the turbine, and the first regeneration of the working fluid from the third heat exchanger or the fourth heat exchanger in accordance with the temperature, volume, pressure or calorie of the working fluid are provided at a position adjacent to the sensing sensor. The warm-up system using the waste heat recovery of the construction machine further comprises a bypass valve for bypassing any one of the heat exchanger or the second regenerative heat exchanger.

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