WO2019013420A1

WO2019013420A1 - Engine system enabling steam generation in association with electricity generation

Info

Publication number: WO2019013420A1
Application number: PCT/KR2018/002187
Authority: WO
Inventors: 류광년; 함진기; 김범주; 이철희
Original assignee: 한국전력공사; 현대중공업 주식회사
Priority date: 2017-07-12
Filing date: 2018-02-22
Publication date: 2019-01-17
Also published as: KR20190007301A

Abstract

An engine system enabling steam generation in association with electricity generation according to the present invention comprises: a waste heat discharge unit having an engine and discharging exhaust gas; a steam generation unit for generating steam by using the waste heat of the exhaust gas discharged by the waste heat discharge unit; and an electricity generation unit which heats an operation fluid used to drive a turbine by using the waste heat of the exhaust gas discharged by the waste heat discharge unit and generates electricity by the driving of the turbine.

Description

An engine system linked to the generation and development of steam

The present invention relates to an engine system in which generation and development of steam are linked.

Generally, the exhaust gas generated by burning fuel in the engine is discharged to the outside.

The heat released is not converted into useful form for the propulsion or power generation of the engine and is abandoned. If some of the waste heat discharged to the outside is recovered and can be recycled as useful energy, it is possible to save fuel, thereby contributing to saving energy.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a steam generator capable of generating steam and generating steam which can be used to generate steam by branching exhaust gas, And to provide an associated engine system.

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve such problems, and it is an object of the present invention to provide a method of producing electricity by heating supercritical carbon dioxide, which is a working oil used for driving a turbine, And the engine system in which generation and development of steam can be linked.

An object of the present invention is to provide an engine system in which exhaust gas is branched and utilized for generating steam, and generation and power generation of steam, which do not require a separate boiler, are linked.

In one example, the engine system in which the generation and the power generation of steam according to the present invention are connected includes a waste heat discharge unit having an engine and exhausting the exhaust gas, a steam generating steam using the waste heat of the exhaust gas discharged from the waste heat exhaust unit And a power generation unit for heating the working fluid used for driving the turbine by using the waste heat of the exhaust gas discharged from the waste heat discharge unit and generating power by driving the turbine.

Accordingly, a part of the exhaust gas can be utilized for power generation, and the remainder can be utilized for generating steam, so that energy can be efficiently used.

Further, some of the exhaust gas can generate electricity by heating supercritical carbon dioxide, which is an operating oil used for driving the turbine, and driving a generator connected to the turbine.

In addition, since the exhaust gas can be branched to be used for generating steam, there is no need to provide a separate boiler for generating steam, so that the cost and the volume of the apparatus are not increased.

1 is a schematic diagram of an engine system in which steam generation and power generation according to Embodiment 1 of the present invention are associated.

2 is a schematic diagram of an engine system in which generation and power generation of steam according to Embodiment 2 of the present invention are linked.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals even though they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

The engine system in which the generation and the power generation of steam according to the present invention are linked is a system in which a part of high temperature exhaust gas generated in various places such as a ship is used for power generation to generate electric power and the remainder is used for generating steam, As waste heat, there is a feature that can utilize renewable energy twice.

실시예Example 1 One

1 is a schematic diagram of an engine system in which steam generation and power generation according to Embodiment 1 of the present invention are associated. The engine system in which the generation and development of steam are linked includes a waste heat discharge unit 200, a steam generation unit 300, and a power generation unit 100.

The waste heat discharging unit 200 can be configured to discharge the hot exhaust gas. The waste heat discharging unit 200 may include an engine 210, and the exhaust gas may be exhaust gas discharged from the engine 210. The steam generating unit 300, and the power generating unit 100 can be configured to efficiently utilize the waste heat of the exhaust gas.

The steam generating unit 300 may be configured to generate steam by using the waste heat of the exhaust gas discharged from the waste heat discharging unit 200. The power generating unit 100 may be configured to generate steam by using exhaust gas discharged from the waste heat discharging unit 200 Can be configured to heat the working fluid used to drive the turbine (40) and generate electricity by driving the turbine (40) using the waste heat of the turbine (40).

The power generation unit 100 includes a compression section 10 for compressing the working fluid, a heating section 20 for heating the working fluid discharged from the compression section 10 and supplying the heated working fluid to the turbine 40, And a cooling unit 50 for cooling the working fluid discharged from the turbine 40.

The power generation unit 100 may further include a circulation line 101. The compression section 10, the heating section 20, the turbine 40, and the cooling section 50 are disposed in the circulation line 101, May be configured to compress, heat, expand, and cool the flowing working fluid along the circulation line (101). Here, the working fluid may include supercritical carbon dioxide.

The working fluid of the power generation unit 100 may be supercritical carbon dioxide and supercritical carbon dioxide may flow along the circulation line 101 to drive the generator 41 connected to the turbine 40 to produce electricity .

For example, the compression section 10 may be configured to compress supercritical carbon dioxide, which is a hydraulic fluid, at an ultra-high pressure higher than a critical pressure. For example, the compression section may be configured to compress the supercritical carbon dioxide beyond 20 to 22 atmospheres.

At this time, the heating unit 20 may be provided to form supercritical carbon dioxide, which is an operating oil, at a predetermined temperature or higher. The heating section 20 can be configured to heat the working fluid through the exhaust gas and compressed air having a high temperature by the air compressor 230 to be described later. For example, after passing through the compression section 10, the working fluid is supplied to the heating section 20 to be in a supercritical state of high temperature and high pressure, and the working fluid may be configured to drive the turbine 40. For example, the predetermined temperature of supercritical carbon dioxide as the working oil may be in the range of 150 to 350 ° C.

The heating section 20 may include a first heating heat exchanger 21. The first heating heat exchanger (21) receives a part of the exhaust gas discharged from the waste heat discharging unit (200) and can heat the working fluid through heat exchange with the working fluid.

The waste heat discharging unit 200 may include a turbocharger 220 and an air compressor 230. The turbocharger 220 can be operated by receiving a part of the exhaust gas discharged from the engine 210.

The air compressor 230 receives the power of the turbocharger 220 and can compress the air used in the engine 210 included in the waste heat discharging unit 200. For example, the air compressor 230 and the turbocharger 220 may be connected by a shaft, and the turbocharger 220 may be driven by exhaust gas. The air compressor 230 can compress the air used in the engine 210 by the rotation of the turbocharger 220.

Further, the heating section 20 may further include a second heating heat exchanger 22. The second heating heat exchanger 22 can receive the compressed air compressed by the turbo charger 220 to heat the working fluid.

Specifically, the working fluid flowing through the circulation line 101 can be heat-exchanged with the compressed air through the second heating heat exchanger 22, and the compressed air is heat-exchanged with the working fluid, As shown in FIG. The compressed air discharged from the air compressor 230 can be used as a heat source for driving the power generation unit 100 by being used to heat the working fluid. Here, the second heating heat exchanger 22 may be provided on the upstream side of the first heating heat exchanger 21 on the basis of the flow direction of the working fluid on the circulation line 101 on which the working fluid circulates.

The power generation unit 100 may further include a recovery unit 30. The return heat exchanger 30 is provided with a working fluid before being discharged from the compression section 10 and flowing into the second heat exchanger 22 and a working fluid discharged from the turbine 40 and flowing into the cooling section 50 Heat exchange can be performed.

The working fluid flowing along the circulation line 101 may be branched and partly supplied to the recovery unit 30 and the remainder may be supplied to the second heating heat exchanger 22. [ A first portion that is part of the working fluid discharged from the compression section 10 may be supplied to the recovery section 30 and the remaining second section may be supplied to the second heating heat exchanger 22. [

The first and second portions may be joined together after the respective heat exchanges in the reheating section 30 and the second heating heat exchanger 22 and supplied together to the first heating heat exchanger 21. The working fluid flowing along the circulation line 101 can reach the maximum temperature by being supplied to the first heating heat exchanger 21 after passing through the second heating heat exchanger 22 or the recovery unit 30. [

The power generation unit 100 may further include a flow distribution valve 119. The flow rate distribution valve 119 controls the amount of the working fluid to be supplied to the recovery unit 30 as the first portion and the amount of the working fluid to be supplied to the second heating heat exchanger 22 as the second portion among the working fluid discharged from the compression portion 10 The amount of working fluid to be controlled can be adjusted. The flow rate distribution valve 119 may be provided at a branch point to the recovery unit 30 and the second heating heat exchanger 22 on the circulation line 101. [

For example, a first valve 102 may be provided upstream of the flow distribution valve 119 on the circulation line 101. The first valve 102 may be configured to regulate the amount of working fluid flowing along the circulation line 101. The amount of the working fluid discharged from the compression section 10 is supplied to the heating section 20 and the returning section 30 according to the degree of opening of the first valve 102.

For example, the first valve 102 may perform a closing operation when the turbine 40, the engine 210, the turbocharger 220, etc. are one of a load fluctuation, an overload, and an emergency.

For example, the emergency situation may be a leakage due to the breakage of the circulation line 101 near the connection point where the second heat exchanger 22 and the heat exchanger 30 are connected.

The power generation unit 100 may further include a first bypass line 111 and an inventory tank 110 for controlling the flow rate of the working fluid. The first bypass line 111 can connect the outlet end of the compression section 10 and the inlet end of the cooling section 50 on the circulation line 101.

The inventory tank 110 may be installed on the first bypass line 111 and some of the working fluid may be supplied to the inventory tank 110. The inventory tank 110 can regulate the temperature, pressure and flow rate of the working fluid circulating in the circulation line 101 and can receive a part of the working fluid.

For example, the upper valve portion 112 provided at the upper end of the inventory tank 110 may be provided to adjust the amount of the working fluid to be accommodated in the inventory tank 110.

Specifically, the outlet side of the compression section 10 on the circulation line 101 can be at a higher pressure than the outlet end of the turbine 40, and the temperature and pressure of the working fluid flowing along the circulation line 101 can be relatively high have. The upper valve portion 112 according to the present invention can adjust the temperature and pressure of the working fluid flowing along the circulation line 101, the circulating flow rate, and the like. Here, when the temperature or the flow rate of the working fluid is adjusted, the pressure of the working fluid may be changed.

More specifically, in order to increase the pressure of the working fluid flowing on the circulation line 101, the upper valve portion 112 is closed and the lower valve portion 118 is opened to circulate the working fluid accommodated in the inventory tank 110 Line 101 as shown in FIG. The higher the pressure of the working fluid flowing along the circulation line 101, the higher the density of the working fluid and the mass flow rate.

Conversely, to lower the pressure of the working fluid flowing on the circulation line 101, the lower valve portion 118 may be closed and the upper valve portion 112 may be opened to supply the operating fluid to the inventory tank 110 have. The lower the pressure, the lower the working fluid density and the mass flow rate. Thus, the inventory tank 110 can regulate the temperature, flow rate, and pressure of the working fluid flowing through the circulation line 101 by receiving a part of the working fluid.

On the other hand, when the temperature of the exhaust gas is higher than a predetermined temperature (200 to 400 ° C), the load of the engine 210 and the turbocharger 220 is changed, and the first heating heat exchanger 21 and the second heating heat exchanger 22 Lt; RTI ID = 0.0 > heat exchange < / RTI > The first valve 102 according to the present invention can perform the closing operation gradually when the load variation between the engine 210 and the turbocharger 220 is severe. At this time, the working fluid flowing along the circulation line 101 can flow to the second bypass line 113 to be described later, and then the first valve 102 can perform the opening operation gradually.

The power generation unit 100 may include a second bypass line 113 and a first control valve 114. The second bypass line 113 can bypass the working fluid of the circulation line 101 by connecting the outlet end of the compression section 10 and the inlet end of the cooling section 50 on the circulation line 101. [ Here, the first control valve 114 is provided on the second bypass line 113, and the amount by which the working fluid discharged from the compression section 10 is bypassed to the second bypass line 113 can be adjusted.

The first valve 102 can control the flow rate of the working fluid supplied to the second heating heat exchanger 22 or the recovery unit 30 together with the first control valve 114. [ Specifically, at the start-up of the system, the first valve 102 is closed and the first control valve 114 is opened for the step-up, so that the working fluid can be circulated to the second bypass line 113. Thereafter, when the pressure on the circulation line 101 increases to a predetermined pressure, the first valve 102 is opened and the first control valve 114 can be closed.

For example, the pressure of the working fluid flowing on the circulation line 101 at the start of the engine system may be in the range of 1 to 50 barA, but the pressure of the first valve 102, The control valve 114 can be adjusted.

The power generation unit 100 may further include a third bypass line 115 and a second control valve 116. The third bypass line 115 may connect the inlet end of the first heat exchanger 21 on the circulation line 101 and the outlet end of the turbine 40. Some of the working fluid flowing along the circulation line 101 may be bypassed through the third bypass line 115. [

The second control valve 116 can be installed on the third bypass line 115 and the amount of working fluid bypassed through the third bypass line 115 can be adjusted. By the adjustment of the second control valve 116, part of the working fluid can be bypassed to the outlet end of the turbine 40 without being supplied to the first heating heat exchanger 21.

For example, a second valve 103 may be provided to regulate the amount of working fluid exiting the first heat exchanger 21 on the circulation line 101 being fed to the turbine 40.

For example, the second valve 103 may control the flow rate of the working fluid flowing into the turbine 40 together with the second control valve 116. Specifically, when a sudden high temperature working fluid is supplied to the turbine 40, the turbine 40 may be subject to wear due to heat.

Therefore, according to the present invention, at the time of starting the engine system, the second valve 103 performs a gradual close operation, and the second control valve 116 performs a gradual opening operation. Thereafter, the second valve 103 is opened and the second control valve 116 is closed slowly, thereby minimizing the impact of the heat that the turbine 40 receives. For example, the first valve 102 and the second valve 103 may be throttle valves, but are not limited thereto.

The first bypass line 111, the inventory tank 110 and the upper and

lower valve units

112 and 118 are connected to the circulation line 101 for controlling the pressure, temperature and flow rate of the working fluid discharged from the compression unit 10. [ As shown in FIG. The valves 102,103,114 and 116 and the second and

third bypass lines

113 and 115 may be provided to cope with load fluctuations and emergency situations of the turbine 40, the turbocharger 220, the engine 210, and the like.

The turbine 40 may be connected to the generator 41 to drive the generator 41. The power generation unit 100 can heat the working fluid through the waste heat to drive the generator 41 and the electric energy produced from the generator 41 can be used as electric power. That is, the present invention can recover the exhaust gas from the power generation unit 100 to produce electric power.

A part of the discharged exhaust gas may be supplied to the heating unit 20, and the remainder of the exhaust gas may be supplied to the steam generating unit 300.

Valves

212 and 213 or dampers (not shown) may be provided at the inlet ends of the first heating heat exchanger 21 and the evaporator 330, respectively. The

valve units

212 and 213 or the damper (not shown) can adjust the supply amount of the exhaust gas supplied to the first heat exchanger 21 and the evaporator 330 according to the degree of opening.

As shown in the figure, the steam generating unit 300 may include a drum 320, a separator 310, and an evaporator 330 so that the exhaust gas is utilized in generating steam.

The drum 320 can be supplied with liquid water. Further, the drum 320 can separate and discharge the steam in the stored liquid water and steam.

The burner 310 may be configured to heat the liquid water to be supplied to the drum 320. The economizer 310 may be provided on a supply line that supplies liquid water to the drum.

The evaporator 330 may be provided on the flow line 321 that returns the liquid to the drum 320 after draining the liquid water from the drum 320. A pump (not shown) may be provided on the flow line 321, and the liquid water can be forcedly circulated by the operation of a pump (not shown). The evaporator 330 can evaporate at least a portion of the liquid water flowing out of the drum 320.

The evaporator 330 is disposed upstream of the absorbent unit 310 on the line through which the exhaust gas discharged from the waste heat discharging unit 200 is discharged so that the evaporator 330 is heated by the economizer 310 ). &Lt; / RTI >

A part of the exhaust gas discharged from the waste heat discharging unit 200 is heat-exchanged with the liquid water through the evaporator 330 to heat the liquid water. Thereafter, the rubber band 310 can receive the exhaust gas heat-exchanged in the evaporator 330 and again heat the liquid water.

Here, the drum 320, the cutlery 310, and the evaporator 330 may be installed on a line through which the exhaust gas is discharged, and the steam may be separated into high pressure and low pressure.

According to the present invention, since the waste heat discharging unit 200 and the steam generating unit 300 are linked, there is no need to install a separate boiler.

For example, an engine system in which steam generation and power generation are linked can be applied to a ship, and a heat source of compressed air, which compresses the exhaust gas discharged from the engine 210 of the ship and the engine 210, (300) and the power generation unit (100).

실시예Example 2 2

2 is a schematic diagram of an engine system in which generation and power generation of steam according to Embodiment 2 of the present invention are linked. In the following, the same reference numerals are used for the same constituent elements, and redundant explanations are omitted.

2, the waste heat discharging unit 200 includes a turbocharger 220 that receives and operates a part of the exhaust gas discharged from the engine 210, a turbocharger 220 that is connected to the turbocharger 220, And an air cooler 250 for cooling the compressed air discharged from the air compressor 230. The air compressor 230 is operated by the air compressor 230 and compresses the air used in the engine 210.

The engine 210 may be supplied with compressed air through an air compressor 230 connected to the turbocharger 220. The air compressed in the air compressor 230 can be supplied to the engine 210 after the temperature rises in the compression process, cooled in the cooler 250 provided at the front end of the engine 210, and then cooled.

The heating section 20 may include a second heating heat exchanger 23. The second heating heat exchanger 23 may be provided on the upstream side of the first heating heat exchanger 21 on the basis of the flow direction of the working fluid on the circulation line 101 on which the working fluid circulates.

The second heating heat exchanger (23) can receive the exhaust gas heat-exchanged in the first heating heat exchanger (21) and heat the working fluid.

This is because a plurality of first and

second heat exchangers

21 and 23 are disposed on the exhaust line 211 through which the exhaust gas is exhausted so that the working fluid flowing in the circulating line 101 is heat- So that the generator 41 can be driven.

A first portion which is part of the working fluid discharged from the compression section 10 can be supplied to the recovery section 30 and a second part which is the remainder of the working fluid can be supplied to the second heating heat exchanger 23. [

The recovery unit 30 is configured to heat the working fluid before being discharged from the compression unit 10 and flowing into the second heating heat exchanger 23 and the working fluid discharged from the turbine 40 and before flowing into the cooler 250 .

The first and second portions may be joined together after the respective heat exchanges in the reheating section 30 and the second heating heat exchanger 23 and supplied together to the first heating heat exchanger 21.

For example, the first heating heat exchanger 21 may be disposed upstream of the second heating heat exchanger 23 on the exhaust line 211 to which the exhaust gas is supplied, The heat can be supplied to the first heating heat exchanger 21 after reaching the heat recovery unit 23 or the recovery unit 30 to reach the maximum temperature.

Accordingly, a part of the high temperature exhaust gas is utilized for power generation to generate electric power, and the remainder is utilized for generating steam, so that energy can be efficiently used.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims

A waste heat discharging unit having an engine and discharging exhaust gas;

A steam generating unit for generating steam by using waste heat of the exhaust gas discharged from the waste heat discharging unit; And

Wherein the generation and the power generation of the steam including the power generation unit for heating the working fluid used for driving the turbine using the waste heat of the exhaust gas discharged from the waste heat discharge unit and generating power by driving the turbine are linked.
The method according to claim 1,

The power generation unit includes:

A compression unit for compressing the working fluid;

A heating unit for heating the working fluid discharged from the compression unit and supplying the heated working fluid to the turbine; And

And a cooling unit for cooling the working fluid discharged from the turbine.
The method of claim 2,

Wherein the heating unit includes a first heating heat exchanger that receives a part of the exhaust gas discharged from the waste heat discharging unit and heats the working fluid through heat exchange.
The method of claim 3,

The waste heat discharging unit includes:

A turbocharger for receiving and operating part of the exhaust gas discharged from the engine; And

And an air compressor that operates in conjunction with the turbocharger and compresses the air used in the engine.
The method of claim 4,

Wherein the heating unit is provided on an upstream side of the first heating heat exchanger with respect to a flow direction of the working fluid on a circulation line through which the working fluid circulates and is supplied with compressed air discharged from the air compressor, And a second heating heat exchanger for heating the working fluid.
The method of claim 5,

The power generation unit may further include a recovery unit for exchanging heat between the working fluid before being discharged from the compression unit and flowing into the first heating heat exchanger and the working fluid discharged from the turbine before flowing into the cooling unit,

A first portion which is a part of the working fluid discharged from the compression portion is supplied to the recovery heat exchanger, and the remaining second portion is supplied to the second heating heat exchanger,

Wherein the first and second portions are associated with generation and power generation of steam supplied together with the first heat exchanger after heat exchange in the second heat exchanger and the second heat exchanger.
The method of claim 6,

Wherein the power generation unit controls the amount of the working fluid to be supplied to the recovery unit as the first portion and the amount of the working fluid to be supplied to the second heating heat exchanger as the second portion among the working fluid discharged from the compression unit An engine system in which the generation and development of steam, further comprising a flow distribution valve, is associated.
The method of claim 3,

The heating unit is provided on an upstream side of the first heating heat exchanger with respect to a flow direction of the working fluid on a circulation line through which the working fluid circulates, and supplies the exhaust gas discharged after heat exchange in the first heating heat exchanger And a second heat exchanger for heating the working fluid through heat exchange,
The method of claim 8,

The waste heat discharging unit includes a turbo charger that receives and operates part of the exhaust gas discharged from the waste heat discharging unit;

An air compressor operating in conjunction with the turbocharger and compressing the air used in the engine; And

And an air cooler for cooling the compressed air discharged from the air compressor.
The method of claim 2,

The power generation unit includes:

A circulation line through which the working fluid circulates;

A first bypass line connecting the outlet end of the compression section and the inlet end of the cooling section on the circulation line to bypass some of the working fluid of the circulation line; And

Further comprising an inventory tank installed on the first bypass line for regulating the pressure and the flow rate of the working fluid circulating through the circulation line.
The method of claim 2,

The power generation unit includes:

A circulation line through which the working fluid circulates;

A second bypass line connecting the outlet end of the compression section and the inlet end of the cooling section on the circulation line and bypassing a part of the working fluid of the circulation line; And

Further comprising a first control valve disposed on the second bypass line for regulating the amount of working fluid bypassed through the second bypass line.
The method of claim 3,

The power generation unit includes:

A circulation line through which the working fluid circulates;

A third bypass line connecting the inlet end of the first heating heat exchanger and the outlet end of the turbine on the circulation line to bypass some of the working fluid of the circulation line to the turbine; And

Further comprising a second control valve provided on the third bypass line for regulating the amount of working fluid bypassed through the third bypass line.
The method according to claim 1,

The steam generating unit includes:

A drum for separating and discharging steam from the stored liquid water and steam;

An archer provided on a supply line for supplying liquid water to the drum and heating the liquid water supplied to the drum; And

And an evaporator provided on a flow line for allowing the liquid to flow out of the drum and then returning to the drum to evaporate at least a portion of the liquid water flowing out of the drum,

The evaporator receives a part of the exhaust gas discharged from the waste heat discharging unit, heats the liquid water through heat exchange,

Wherein the burner is connected to generation and power generation of steam, which receives the exhaust gas discharged from the evaporator after heat exchange and heats the liquid water through heat exchange.
The method according to claim 1,

Wherein the working fluid is associated with the generation and development of steam including supercritical carbon dioxide.