KR20170138303A - Floating marine structure with electric power generator - Google Patents

Abstract

Disclosed is a floating marine structure. According to the present invention, the floating marine structure removes nitrogen oxide contained in the exhaust gas of a waste heat recovery boiler of a power generation unit in a selective catalytic reduction reactor, and the selective reduction catalyst reactor receives ammonia stored in an ammonia tank and reduces nitrogen oxide into nitrogen and moisture to remove the same. In addition, the ammonia in the ammonia tank must be in a liquid state to store a large amount of ammonia in the ammonia tank. Since the ammonia of the ammonia tank is maintained in a liquid state by using cold heat of liquefied natural gas (LNG) supplied from an LNG tank to a regasification unit, a separate cold heat source to maintain the ammonia of the ammonia tank in a liquid state is not required. Therefore, it is possible to reduce the costs.

Description

TECHNICAL FIELD [0001] The present invention relates to a floating structure having a power generation system,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating structure having a power generation system capable of storing ammonia in a liquid state for removing nitrogen oxides by using cold of LNG (Liquefied Natural Gas).

Today, as a concern for the environment, there is growing interest in environmentally friendly power generation systems, and there is a power generation system that uses natural gas as a power generation fuel as an environmentally friendly power generation system.

However, in order to build a power generation system using natural gas as a power source on the ground, infrastructure such as an LNG tank and a gas supply device is required. Therefore, natural gas is used as a power generation fuel It is difficult to build a power generation system to use.

In order to solve the above-mentioned problems, a floating system in which a power generation system is installed on a hull equipped with a device for storing and regenerating gas, power is generated from the hull, Has been used.

The power generation system has a waste heat recovery boiler for generating steam using high temperature exhaust gas, and the exhaust gas flowing into the waste heat recovery boiler is exhausted from the waste heat recovery boiler after generating steam. However, since the exhaust gas flowing into the waste heat recovery boiler contains nitrogen oxide which causes environmental pollution, it is necessary to exhaust the exhaust gas after removing the nitrogen oxide.

As a method of removing nitrogen oxide contained in the exhaust gas, there is a selective catalytic reduction method in which a nitrogen oxide is reduced to nitrogen and water using a catalyst. In the case of selective catalytic reduction, when ammonia is injected into a selective catalytic reduction (SCR) reactor, the nitrogen oxides are reduced to nitrogen and water to be removed.

An ammonia tank for storing ammonia is provided at one side of the waste heat recovery boiler and supplies ammonia to a reduction catalyst reactor installed inside the waste heat recovery boiler. At this time, it is necessary to store the ammonia in a liquid state to store a large amount of ammonia in the ammonia tank.

Conventionally, there is a disadvantage that a separate cold source must be provided in order to keep the ammonia in the ammonia tank in a liquid state, thereby increasing the cost.

Prior art for removing nitrogen oxide using ammonia is disclosed in Korean Patent Laid-Open Publication No. 10-1998-0024189 (July 06, 1998).

It is an object of the present invention to provide a floating structure capable of solving all the problems of the prior art as described above.

Another object of the present invention is to provide a floating structure capable of reducing costs.

According to an aspect of the present invention, there is provided a floating structure including: a hull; An LNG tank installed in the hull and storing LNG (Liquefied Natural Gas); A regeneration unit installed in the hull to supply LNG from the LNG tank and to vaporize the LNG; A generator having a waste heat recovery boiler installed in the hull to generate natural gas (NG) vaporized in the regeneration unit as fuel, and a waste heat recovery boiler for receiving exhaust gas generated at the time of generation to generate steam; And an ammonia tank for storing ammonia supplied to a selective catalytic reduction (SCR) reactor of the waste heat recovery boiler for removing nitrogen oxides contained in exhaust gas of the waste heat recovery boiler, wherein the ammonia in the ammonia tank The liquid state can be maintained by the cold heat of the LNG.

In the floating marine structure according to the present embodiment, the nitrogen oxide contained in the exhaust gas of the waste heat recovery boiler of the power generation unit is removed from the selective catalytic reduction reactor, and the reduction catalyst reactor receives ammonia stored in the ammonia tank, Reduce oxides to nitrogen and water. And, the ammonia in the ammonia tank must be in a liquid state so that a large amount of ammonia can be stored in the ammonia tank. At this time, since the ammonia in the ammonia tank is kept in a liquid state by using the cold heat of LNG (Liquefied Natural Gas) supplied from the LNG tank to the regeneration unit, a separate heat source for maintaining the ammonia in the ammonia tank in a liquid state ). Therefore, the cost may be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a configuration of a floating structure according to an embodiment of the present invention; FIG.
2 is an enlarged view of the waste heat recovery boiler shown in Fig.
3 is a view showing a configuration of a floating type floating structure according to another embodiment of the present invention.

It should be noted that, in the specification of the present invention, the same reference numerals as in the drawings denote the same elements, but they are numbered as much as possible even if they are shown in different drawings.

Meanwhile, the meaning of the terms described in the present specification should be understood as follows.

The word " first, "" second," and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms.

It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It should be understood that the term "at least one" includes all possible combinations from one or more related items. For example, the meaning of "at least one of the first item, the second item and the third item" means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one.

It should be understood that the term "and / or" includes all possible combinations from one or more related items. For example, the meaning of "first item, second item and / or third item" may include not only the first item, the second item or the third item but also two of the first item, Means a combination of all items that can be presented from the above.

It is to be understood that when an element is referred to as being "connected or installed" to another element, it may be directly connected or installed with the other element, although other elements may be present in between. On the other hand, when an element is referred to as being "directly connected or installed" to another element, it should be understood that there are no other elements in between. On the other hand, other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

Hereinafter, a floating structure according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view showing the construction of a floating structure according to an embodiment of the present invention, and FIG. 2 is an enlarged view of the waste heat recovery boiler shown in FIG.

The floating structure according to the present embodiment may include the hull 110, the LNG tank 120, the regeneration unit 130, and the power generation unit 140.

The hull 110 can float on the water surface by buoyancy and the LNG tank 120 can be installed on the hull 110 to store LNG (Liquefied Natural Gas). The LNG tank 120 is preferably installed in a lower part of the hull 110 and the LNG stored in the LNG tank 120 is in a liquid state at approximately -160 ° C. or lower.

The regeneration unit 130 is installed in the hull 110 and can supply LNG from the LNG tank 120 to vaporize the LNG in a gaseous state and the LNG vaporized in the regeneration unit 130 can be vaporized Temperature can be obtained. The regeneration unit 130 may include a tank for storing the LNG, a pump for discharging the LNG of the tank, a vaporizer for vaporizing the LNG discharged from the tank, and the like.

The power generation unit 140 can be installed in the hull 110 and can generate electricity using NG (Natural Gas) vaporized in the regeneration unit 130 as the power generation fuel. The power generation unit 140 will be described in detail.

The power generation section 140 may include a gas turbine 151, a waste heat recovery boiler 160, a steam turbine 153, and a condenser 155.

The gas turbine 151 can be driven by the combustion gas generated when the vaporized NG supplied from the regeneration unit 130 is burned and is generated while the generator 151a is driven by the gas turbine 151. [ The combustion gas driven by the gas turbine 151 is discharged to the outside of the gas turbine 151 and the exhaust gas discharged from the gas turbine 151 can be introduced into the waste heat recovery boiler 160.

The waste heat recovery boiler 160 generates steam using the exhaust gas discharged from the gas turbine 151 and the steam turbine 153 is driven by the steam discharged from the waste heat recovery boiler 160. Then, the other generator 153a is driven by the steam turbine 153 to generate power.

The steam that drives the steam turbine 153 is discharged and condensed in the condenser 155 and the condensed water discharged from the condenser 155 can be reintroduced into the waste heat recovery boiler 160.

The floating structure according to the present embodiment burns vaporized NG and drives the gas turbine 151 using combustion gas generated during combustion of the NG that has been vaporized. The gas turbine 151 drives the generator 151a, And is developed first. The waste heat recovery boiler 160 generates steam by using the exhaust gas discharged from the gas turbine 151. The steam generated by the waste heat recovery boiler 160 drives the steam turbine 153, The generator 153a is secondarily driven by the generator 153. Therefore, the power generation efficiency can be improved.

Most of the electricity generated in the power generation unit 140 is supplied to the use place on the land, and the rest can be used in the floating sea structure itself.

The hull 110 may be provided with a propelling unit 190 for moving the hull 110. The propelling unit 190 may include a power unit for rotating the propeller and a waste heat recovery boiler. The power unit may rotate the propeller while being driven by a combustion gas generated during combustion of a propellant fuel such as gas or oil, and the waste heat recovery boiler uses steam exhausted from exhaust gas discharged after driving the power unit Can be generated.

The waste heat recovery boiler 160 will be described with reference to FIG.

The waste heat recovery boiler 160 may include a main body 161. The main body 161 has an inlet 161a through which the exhaust gas discharged from the gas turbine 151 flows, And a discharging portion 161b formed by a plurality of nozzles.

An economizer 163a for heating the water by the residual heat of the exhaust gas flowing into the main body 161 can be installed in the main body 161 and an economizer 163a can be installed between the inlet 161a and the economizer 163a An evaporator 163b for vaporizing the water delivered from the economizer 163a may be installed in the main body 161 of the evaporator 163. Inside the main body 161 between the inlet 161a and the evaporator 163b, And a superheater 163c for heating the steam delivered from the steam generator 163b to generate superheated steam.

 The superheated steam generated in the superheater 163c can generate power while the steam turbine 153 is driven.

At this time, water is stored in one side of the main body 161, and at the same time, a water tank / deaerator 165 for removing oxygen dissolved in the water can be installed, and water in the water tank / deaerator 165 is supplied to the economizer (163a). The water heated in the economizer 163a may be introduced into the evaporator 163b through the drum 163d.

2, the exhaust gas flows into the left side surface of the main body 161 and is discharged to the right side surface side, and water can flow in from the right side surface of the main body 161 and be discharged to the left side surface side.

The economizer 163a, the evaporator 163b, the superheater 163c, and the drum 163d may be installed in the inflow portion 161a and the discharge portion 161b, respectively. At this time, the economizer 163a, the evaporator 163b, the superheater 163c, and the drum 163d provided in the main body 161 on the inflow portion 161a are the high pressure region 163, The evaporator, the superheater, and the drum installed inside the low-pressure region 161 are the low-pressure region 164.

The exhaust gas flowing into the main body 161 through the inflow portion 161a may contain nitrogen oxides that cause environmental pollution. Therefore, after the nitrogen oxide contained in the exhaust gas flowing into the body 161 is removed, the exhaust gas must be discharged to the exhaust portion 161b.

The waste heat recovery boiler 160 according to an embodiment of the present invention can remove nitrogen oxides contained in the exhaust gas using a selective catalytic reduction (SCR) reactor 167. Since the optimum denitrification efficiency is generated when the temperature of the exhaust gas is 300 to 400 ° C, the SCR reactor 167 is provided between the superheater 163c and the evaporator 163b in which the temperature of the exhaust gas is in the range of 300 to 400 ° C Can be installed.

The SCR reactor 167 uses a catalyst and acts with ammonia supplied separately to reduce the nitrogen oxides contained in the exhaust gas to nitrogen and moisture. In order to supply ammonia to the SCR reactor 167, an ammonia tank 171 in which ammonia is stored may be installed at one side of the waste heat recovery boiler 160.

The ammonia supplied to the SCR reactor 167 is in a liquid state. However, the ammonia stored in the ammonia tank 171 must be able to be maintained in a liquid state, so that a large amount of ammonia can be stored in the ammonia tank 171.

The floating structure according to an embodiment of the present invention can maintain the ammonia of the ammonia tank 171 in a liquid state by using the cooling of the LNG.

The LNG line 173 for supplying LNG from the LNG tank 120 to the regeneration unit 130 is heat-exchanged with the ammonia tank 171 in order to maintain the ammonia in the ammonia tank 171 in a liquid state by the cold heat of the LNG .

That is, the LNG line 173 which is provided between the LNG tank 120 and the regeneration unit 130 and supplies the LNG of the LNG tank 120 to the regeneration unit 130 is extended to allow the heat exchange of the ammonia tank 171 have. The meaning of the heat exchange between the LNG conduit 173 and the ammonia tank 171 implies that the LNG of the LNG conduit 173 and the ammonia of the ammonia tank 171 exchange heat. Then, the ammonia in the ammonia tank 171 is cooled by the LNG at about -160 DEG C or lower to maintain the liquid state.

The floating structure according to an embodiment of the present invention removes the nitrogen oxides contained in the exhaust gas of the waste heat recovery boiler 160 of the power generation unit 140 in the SCR reactor 167 and the SCR reactor 167 removes ammonia Ammonia stored in the tank 171 is supplied to reduce nitrogen oxides to nitrogen and moisture to be removed. Further, the ammonia in the ammonia tank 171 must be in a liquid state so that a large amount of ammonia can be stored in the ammonia tank 171. At this time, since the ammonia in the ammonia tank 171 is maintained in a liquid state by using the cold heat of the LNG, there is no need for a separate heat source for keeping the ammonia in the ammonia tank 171 in a liquid state. Therefore, the cost is reduced.

FIG. 3 is a view showing a structure of a floating structure according to another embodiment of the present invention, and only differences from FIG. 1 will be described.

As shown, the ammonia tank 171 can indirectly exchange heat with the LNG.

In detail, the LNG line 173 for supplying LNG from the LNG tank 120 to the regeneration unit 130 and the heat exchanger 181 for heat-exchanging one side may be provided. A cooling medium circulation conduit 183 may be provided in which one side exchanges heat with the other side of the heat exchanger 181, the other side exchanges heat with the ammonia tank 171, and a cooling medium flows into the inside thereof to circulate.

The LNG conduit 173 and the ammonia tank 171 exchange heat with each other via the heat exchanger 181 and the cooling medium circulation conduit 183 so that the ammonia in the ammonia tank 171 maintains a liquid state.

The heat exchange between the LNG conduit 173 and the heat exchanger 181 means that the LNG of the LNG conduit 173 is exchanged with the heat exchanger 181. The heat exchanger 181 and the cooling medium circulation conduit 183 Means that the heat exchanger 181 exchanges heat with the cooling medium of the cooling medium circulation conduit 183 and the cooling medium circulation conduit 183 and the ammonia tank 171 exchange heat, It is natural that the cooling medium of the medium circulation conduit 183 and the ammonia of the ammonia tank 171 exchange heat.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of. Therefore, the scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention.

120: LNG tank
130:
140:
160: Waste Heat Recovery Boiler
167: reduction catalyst reactor
171: Ammonia tank

Claims (3)

hull;
An LNG tank installed in the hull and storing LNG (Liquefied Natural Gas);
A regeneration unit installed in the hull to supply LNG from the LNG tank and to vaporize the LNG;
A generator having a waste heat recovery boiler installed in the hull to generate natural gas (NG) vaporized in the regeneration unit as fuel, and a waste heat recovery boiler for receiving exhaust gas generated at the time of generation to generate steam;
And an ammonia tank for storing ammonia supplied to a selective catalytic reduction (SCR) reactor of the waste heat recovery boiler for removing nitrogen oxides contained in exhaust gas of the waste heat recovery boiler,
Wherein the ammonia in the ammonia tank is maintained in a liquid state by cold heat of the LNG. The method according to claim 1,
An LNG line for supplying LNG to the regeneration unit is installed in the LNG tank,
Wherein the LNG line and the ammonia tank exchange heat. The method according to claim 1,
An LNG line for supplying LNG to the regeneration unit is installed in the LNG tank,
A heat exchanger in which one side exchanges heat with the LNG duct;
Further comprising a cooling medium circulation line through which the cooling medium circulates, one side of which exchanges heat with the other side of the heat exchanger, and the other side of which exchanges heat with the ammonia tank.

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