KR-20260063323-A - Engine waste heat recovery power generation system and ship including the same

KR20260063323AKR 20260063323 AKR20260063323 AKR 20260063323AKR-20260063323-A

Abstract

A waste heat recovery power generation system for an engine is provided by one embodiment of the present invention. A waste heat recovery power generation system for an engine according to one embodiment of the present invention may include a power generation unit comprising: a first economizer installed on an exhaust pipe that discharges exhaust gas generated by the combustion of fuel in an engine and supplies a first steam generated by heat exchange between the exhaust gas and a first feed water supplied from a first water supply pipe to a steam consumption point; a second economizer installed on an exhaust pipe downstream of the first economizer and generating high-temperature water by heat exchange between the exhaust gas and a second feed water supplied from a second water supply pipe; a circulation line in which a refrigerant circulates by forming a closed-loop independent cycle; a vaporizer installed on the circulation line and vaporizing the refrigerant by heat exchange with high-temperature water; and an expansion turbine installed on the circulation line downstream of the vaporizer and producing power using the pressure of the vaporized refrigerant.

Inventors

문성재
김보경
김한균
이완준
최우석
하인환

Assignees

삼성중공업 주식회사

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (11)

A first economizer installed on an exhaust pipe that discharges exhaust gas generated by the combustion of fuel in an engine, and which supplies a first steam to a steam consumption point, generated by heat exchange between the exhaust gas and the first feed water supplied from a first water supply pipe; A second economizer installed on the exhaust pipe downstream of the first economizer, which generates high-temperature water by heat-exchanging the second feed water supplied from the second water supply pipe with the exhaust gas, and A waste heat recovery power generation system for an engine comprising a power generation unit including a circulation line in which a refrigerant circulates by forming a closed-loop independent cycle, a vaporizer installed on the circulation line that vaporizes the refrigerant by exchanging heat with the high-temperature water, and an expansion turbine installed on the circulation line downstream of the vaporizer that produces power using the pressure of the vaporized refrigerant.
In Article 1, A first control valve installed on the first water supply pipe to control the flow of the first feed water, and A waste heat recovery power generation system of an engine further comprising a flow sensor installed on a steam transfer pipe connecting the first economizer and the steam consumption point to measure the flow rate of the first steam supplied to the steam consumption point.
In Article 2, A waste heat recovery power generation system of an engine further comprising a first control unit having a correlation equation corresponding to the steam demand of the steam consumer and controlling the first control valve to regulate the flow rate of the first feed water supplied to the first economizer.
In Article 1, A second control valve installed on the second water supply pipe to control the flow of the second feed water, and A waste heat recovery power generation system for an engine further comprising a temperature sensor installed on the exhaust pipe at the downstream end of the second economizer to measure the temperature of the exhaust gas.
In Paragraph 4, A waste heat recovery power generation system of an engine further comprising a second control unit having a correlation equation corresponding to the type of fuel and controlling the second control valve to maintain the measured value of the temperature sensor above a reference temperature by controlling the flow rate of the second feed water supplied to the second economizer.
In claim 1, the power generation unit is, A condenser installed on the circulation line downstream of the expansion turbine to condense the refrigerant, and A waste heat recovery power generation system of an engine further comprising a pressure pump installed on the circulation line between the condenser and the vaporizer to pressurize the refrigerant.
In Article 1, It further includes an auxiliary boiler that receives third feed water from a third water supply pipe, generates second steam, and supplies it to the steam consumption place, The above steam consumption site is a waste heat recovery power generation system of an engine that first receives the above first steam, and if the above first steam is insufficient, receives the above second steam.
In Article 7, A drain line for discharging condensate generated by condensing at least one of the first steam and the second steam at the above steam consumption site, and It further includes a condensate tank connected to the drain line to store the condensate and supply the first feed water to the first water supply pipe, A waste heat recovery power generation system for an engine in which the high-temperature water that has exchanged heat with the refrigerant in the above vaporizer is joined to the drain line and stored in the above condensate tank.
In Article 8, The above second water supply pipe and the above third water supply pipe are each a waste heat recovery power generation system of an engine branched from the above first water supply pipe.
hull; An engine installed on the above hull to generate propulsion and to discharge exhaust gas generated by the combustion of fuel through an exhaust pipe, and A vessel comprising a waste heat recovery power generation system according to any one of claims 1 to 9 connected to the exhaust pipe above.
In Article 10, The above engine is a ship formed as a dual-fuel engine that generates thrust by mixing a first fuel and a second fuel different from the first fuel.

Description

Engine waste heat recovery power generation system and ship including the same The present invention relates to a waste heat recovery power generation system for an engine and a ship including the same. More specifically, it relates to a waste heat recovery power generation system for an engine and a ship including the same, which can maximize the power generation efficiency of a power generation unit and prevent low-temperature corrosion by recovering waste heat from exhaust gases to the maximum extent by adjusting the flow rate of feed water supplied to a first economizer and a second economizer in response to the steam demand of a steam consumer and the sulfur content of the fuel. Generally, ship engines generate power by supplying and burning fuel and air. Typically, heavy fuel oil is used as fuel; however, due to environmental concerns, there is a trend toward adopting dual-fuel engines that use a mixture of heavy fuel oil and eco-friendly fuels such as liquefied natural gas (LNG), methanol, and ammonia ( NH₃ ). Since the exhaust gas generated by the combustion of fuel in these engines is at a high temperature of approximately 200–300°C, it is supplied to an economizer to generate steam through waste heat recovery. The feed water entering the economizer is approximately 80°C, and the saturated steam, typically 7 barg and 165°C, generated through heat exchange with the exhaust gas, is supplied to onboard steam consumption points. At this time, since the amount and temperature of exhaust gas change depending on the engine load, and the amount of steam generated in the economizer also changes in response, a separate auxiliary boiler is provided to supply steam consistently to the steam consumption point. Meanwhile, since the steam demand at the steam consumption point is variable, it is necessary to appropriately adjust the flow rate of the feed water supplied to the economizer to utilize the waste heat from the exhaust gas elsewhere. Additionally, as the dew point temperature that causes low-temperature corrosion changes depending on the sulfur content of the fuel, it is necessary to regulate the flow rate of the feed water supplied to the economizer to maintain the temperature of the exhaust gas above the dew point temperature. Accordingly, there was a need for a waste heat recovery power generation system capable of preventing low-temperature corrosion while recovering the maximum amount of waste heat from exhaust gases, and for a ship including such a system. FIG. 1 is a drawing illustrating a ship including a waste heat recovery power generation system of an engine according to an embodiment of the present invention. Figure 2 is an enlarged view of the waste heat recovery power generation system of the engine in Figure 1. Figures 3 to 6 are operational diagrams for explaining the operation of a waste heat recovery power generation system of an engine. The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components. Hereinafter, with reference to FIGS. 1 to 6, the waste heat recovery power generation system of the engine of the present invention and a ship including the same will be described in detail. The waste heat recovery power generation system of an engine according to an embodiment of the present invention and a ship including the same have the characteristic of being able to maximize the power generation efficiency of a power generation unit and prevent low-temperature corrosion by recovering the waste heat of exhaust gas to the maximum extent by adjusting the flow rate of feed water supplied to a first economizer and a second economizer in response to the steam demand of a steam consumer and the sulfur content of the fuel. Hereinafter, with reference to FIGS. 1 and 2, a waste heat recovery power generation system (1) of an engine and a ship (100) including the same will be described in detail. FIG. 1 is a drawing showing a ship including a waste heat recovery power generation system of an engine according to an embodiment of the present invention, and FIG. 2 is an enlarged drawing showing the waste heat recovery power generation system of the engine of FIG. 1. A vessel (100) according to the present invention includes a hull (2), an engine (3), and a waste heat recovery power generation system (1). The hull (2) forms the outer shape of the ship (100), and its outer surface is formed in a stre