KR20210013486A - Fuel Gas Supply System and Method for Crude Oil Eco-carrier - Google Patents

Abstract

The present invention relates to a fuel gas supply system and a fuel gas supply method for a crude oil carrier, which can use, as a fuel for an engine, volatile organic compounds generated in crude oil storage tanks of a crude oil carrier using liquefied natural gas as a fuel. According to the present invention, the fuel gas supply system for a crude oil carrier comprises: a volatile organic compounds (VOC) collection tank for collecting gaseous VOC discharged from the crude oil storage tanks without changing the phase; a fuel storage tank for storing liquefied natural gas (LNG) to be used as a fuel for the engine; a fuel pump for pressurizing and discharging the LNG stored in the fuel storage tank; a VOC compressor for compressing the VOC discharged from the VOC collection tank at the same pressure as a pressure at which the fuel pump pressurizes the LNG; and a mixer for mixing the liquid LNG pressurized by the fuel pump with the gaseous VOC compressed by the VOC compressor. The engine is a two-stroke diesel cycle engine, and includes: a mixed fuel supply line for connecting the mixer to the engine to transfer the fuel, mixed in the mixer, to the engine; and a VOC supply line for connecting the VOC collection tank to the mixer to transfer the unreformed VOC from the VOC collection tank to the mixer.

Description

Fuel Gas Supply System and Method for Crude Oil Eco-carrier {Fuel Gas Supply System and Method for Crude Oil Eco-carrier}

The present invention relates to a fuel supply system fuel supply method in which volatile organic compounds generated in a crude oil storage tank of a crude oil carrier using liquefied natural gas as fuel can be used as fuel for an engine.

Crude oil carriers are equipped with a number of crude oil storage tanks capable of storing crude oil. In the crude oil storage tank, the stored crude oil is evaporated to generate volatile organic compounds (VOC). In order to keep the pressure in the crude oil storage tank safely, the VOC generated in the crude oil storage tank must be discharged to the outside.

In particular, during the process of loading crude oil into the crude oil storage tank, during laden voyage, and when cleaning the crude oil storage tank after discharging the crude oil to the customer, a significant amount of VOC is generated. .

The composition of VOC contains almost all components of crude oil, that is, organic compounds, stored in crude oil storage tanks. When VOCs are released into the atmosphere, they cause photochemical reactions with nitrogen oxides under the action of sunlight to generate ozone and photochemical oxidizing substances, causing photochemical smog, destruction of the ozone layer, and environmental pollution such as affecting the greenhouse effect.

Due to the harmfulness of VOCs, the International Maritime Organization and the like have partially regulated the unloading of VOCs in some ports. In addition, since VOC emissions to the atmosphere eventually result in the loss of effective substances, it is necessary to find a way to recover and effectively treat VOCs rather than releasing them into the atmosphere.

The technologies that effectively treat VOCs are VOC reduction technology that greatly reduces the amount of VOCs generated during cargo loading, and VOC recovery technology that recovers and processes the generated VOCs without releasing them into the atmosphere (VOC). recovery technology) is being applied.

A typical technology for reducing VOC generation is to reduce the occurrence of negative pressure in the crude oil storage tank when cargo is loaded into the crude oil storage tank, and to control the tank pressure below the vapor pressure of the crude oil.

The VOC recovery technology collects and liquefies the generated VOC, stores it, or supplies it as fuel, and it is possible to mount and use expensive VOC treatment system equipment composed of a package on a ship.

On the other hand, since VOCs generated from crude oil carriers do not meet the methane number of gas engines due to their high content of heavy hydrocarbons, VOCs must be reformed into light hydrocarbons, methane, and supplied using a reformer.

However, fuel supply using a reformer has a problem that additional fuel combustion is essential because maintenance and management are required to maintain the performance of the reformer periodically, and a large amount of heat energy such as steam is required for reforming.

The present invention is an improved fuel supply system fuel supply method for a crude oil carrier so that while using LNG as fuel, VOC generated from a ship can be efficiently supplied as fuel of an engine at a simpler and lower cost, without emitting to the atmosphere Want to provide.

According to an aspect of the present invention for achieving the above object, a VOC collection tank for collecting gaseous Volatile Organic Compounds (VOCs) discharged from a crude oil storage tank without phase change; A fuel storage tank that stores LNG (Liquefied Natural Gas) to be used as fuel for the engine; A fuel pump for pressurizing and discharging the LNG stored in the fuel storage tank; A VOC compressor for compressing VOC discharged from the VOC collection tank to a pressure equal to a pressure at which the fuel pump pressurizes LNG; And a mixer for mixing liquid LNG pressurized by the fuel pump and gaseous VOC compressed by the VOC compressor; wherein the engine is a two-stroke diesel cycle engine, and the mixer and the engine are connected And a mixed fuel supply line for transferring the mixed fuel mixed in the mixer to the engine; And a VOC supply line for transferring the unmodified VOC from the VOC collection tank to the mixer by connecting the VOC collection tank and the mixer; further comprising, a fuel supply system for a crude oil carrier.

Preferably, the mixed fuel of LNG and VOC mixed in the mixer is in a liquid state, and a high pressure pump for compressing the mixed fuel in the liquid state to a high pressure required by the engine; And a carburetor for vaporizing the mixed fuel compressed by the high pressure pump, wherein the mixed fuel vaporized in the carburetor may be supplied as fuel of the engine through the mixed fuel supply line.

Preferably, the VOC valve is installed in the VOC supply line, the opening amount is controlled according to the nitrogen content of the VOC supplied to the mixer from the VOC collection tank; may further include.

Preferably, a control unit for controlling the opening amount of the VOC valve so that the nitrogen content of the mixed fuel mixed in the mixer is less than 30 mol%; may further include.

Preferably, the engine may be a gas engine capable of using 100% ethane gas, 100% natural gas, a mixture of natural gas and VOC, and VOC as fuel.

Preferably, the high pressure pump can compress the mixed fuel to 200 bar to 420 bar.

Preferably, a VOC collection line that connects the crude oil storage tank and the VOC collection tank and transfers VOC containing nitrogen and heavy hydrocarbon components from the crude oil storage tank to the VOC collection tank; further comprising, the VOC, It can be transferred from the crude oil storage tank to the VOC collection tank and from the VOC collection tank to the mixer without a process of removing moisture and nitrogen and a pretreatment process of reforming heavy hydrocarbons into methane.

According to another aspect of the present invention for achieving the above object, the gaseous Volatile Organic Compounds (VOCs) discharged from the crude oil storage tank are collected and stored in a gaseous state without phase change, and LNG to be used as fuel for the engine. And the gaseous VOC, respectively, but compressed at the same pressure with each other, the compressed liquid LNG and the compressed gaseous VOC are mixed, and the mixed fuel of the LNG and VOC is mixed with a two-stroke diesel A method of fueling a crude oil carrier is provided, which is supplied to a cycle engine.

Preferably, the mixed fuel is further compressed to a high pressure required by the engine, the mixed fuel compressed at the high pressure is vaporized, and the vaporized gaseous mixed fuel may be supplied to the engine.

Preferably, the flow rate of the gaseous VOC to be mixed with the compressed LNG may be adjusted so that the nitrogen content of the mixed fuel is less than 30 mol%.

The fuel supply method of the fuel supply system of the crude oil carrier of the present invention can simplify the process of recovering and recycling VOCs.

In addition, by simplifying the VOC recovery and recycling process, it is possible to maximize the degree of recycling of VOCs generated during the shipping and operation of crude oil.

In particular, since equipment for liquefying VOCs and pretreatment equipment for removing moisture or nitrogen from VOCs is not required, installation costs, area and energy costs can be reduced by omitting additional equipment.

In addition, VOC can be recovered without using electric power, which can reduce the power consumption of the ship.

By supplying the recovered VOC as fuel to the engine, it can be treated environmentally without releasing harmful VOCs into the atmosphere.

1 is a schematic diagram showing a fuel supply system for a crude oil carrier according to a first embodiment of the present invention.
2 is a schematic diagram of a fuel supply system for a crude oil carrier according to a second embodiment of the present invention.
3 is a schematic diagram of a fuel supply system for a crude oil carrier according to a third embodiment of the present invention.

In order to fully understand the operational advantages of the present invention and the object achieved by the embodiments of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the configuration and operation of a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, in adding reference numerals to elements of each drawing, it should be noted that only the same elements are marked with the same numerals as possible, even if they are indicated on different drawings. In addition, the following examples may be modified in various forms, and the scope of the present invention is not limited to the following examples.

In an embodiment of the present invention described below, the liquefied gas may be a liquefied gas containing methane and/or ethane, for example, LNG (Liquefied Natural Gas), LEG (Liquefied Ethane Gas), LPG (Liquefied Petroleum Gas). ), Liquefied Ethylene Gas.

However, in the embodiments to be described later, a representative liquefied gas, LNG, is applied as an example. LNG is mainly composed of methane, and includes ethane, propane, butane, and the like, and its composition may vary depending on the production site.

In addition, a fuel supply method for a fuel supply system for a crude oil carrier according to an embodiment of the present invention to be described later will be described as an example applied to a ship, but may be applied on land.

In addition, in the embodiments to be described later, the ship is described as an example of a crude oil carrier or crude oil tanker that transports the produced crude oil as cargo, but the present invention is a floating crude oil production and storage method that produces crude oil at sea. Floating, Production, Storage and Offloading Unit (FPSO), a petroleum product carrier that transports petroleum products that transports produced crude oil, and a floating storage facility (FSU) that can store the produced crude oil. Storage Unit) and other crude oil storage tanks are provided, and environmental hazards are potential due to the generation of a significant amount of VOC, and can be applied to all ships or floating structures that need to supply fuel to the engine.

In addition, in an embodiment of the present invention described later, the ship may be an LNG fueled ship (LFS) using LNG as a fuel.

In addition, in an embodiment of the present invention to be described later, the liquefied gas and the boil-off gas of the liquefied gas may be used as fuel for an engine, particularly an engine of a ship.

First, a method of supplying fuel to a fuel supply system for a crude oil carrier according to a first embodiment of the present invention will be described with reference to FIG. 1.

A fuel supply system for a crude oil carrier according to a first embodiment of the present invention includes at least one crude oil storage tank 100 for storing crude oil; A VOC collection tank 200 for collecting volatile organic compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 without phase change; A fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as fuel for the engine 1000 of the ship; A fuel pump 400 for pressurizing the LNG stored in the fuel storage tank 300 and discharging it from the fuel storage tank 300 to the outside; A high-pressure pump 501 for compressing the LNG transferred by the fuel pump 400 into a pressure range required by the engine 1000; A vaporizer 601 for vaporizing LNG compressed by the high-pressure pump 501 into natural gas; Using the high-pressure natural gas vaporized by the carburetor 601 as a driving fluid, the low-pressure VOC transferred from the VOC collection tank 200 is sucked, and the natural gas and VOC are mixed and supplied as fuel to the engine 1000 A mixer 701; And the LNG stored in the fuel storage tank 300 is vaporized using the vaporizer 601, the VOC collected in the VOC collecting tank 200, or the mixed fuel of the natural gas and VOC mixed by the mixer 701. It includes; engine 1000 used as fuel.

The VOC collection line (VL1) connects the crude oil storage tank 100 and the VOC collection tank 200, and the VOC discharged from the crude oil storage tank 100 is the VOC collection tank 200 along the VOC collection line (VL1). Is transferred to.

The gaseous VOC discharged from the crude oil storage tank 100 is transferred along the VOC collection line VL1 as it is, and is stored in the gaseous state in the VOC collection tank 200.

That is, the VOC stored in the VOC collection tank 200 in this embodiment is transferred from the crude oil storage tank 100 to the VOC storage tank 200, while being stored in the VOC storage tank 200, and VOC storage A phase change does not occur while being transferred from the tank 200 to the mixer 701 along the VOC supply line VL2.

In addition, the VOC collection tank 200 of this embodiment is provided with a capacity smaller than that of one crude oil storage tank 100.

The VOC discharged from the crude oil storage tank 100 contains not only hydrocarbon components of various carbon atoms, but also impurities such as moisture and nitrogen.

Although the composition of the VOC discharged from the crude oil storage tank 100 varies depending on the composition of the crude oil, in general, propane and butane (especially, normal butane) are the main components. , Heptane, and the like.

In addition, when loading crude oil into the crude oil storage tank 100 or discharging crude oil from the crude oil storage tank 100, the crude oil is used as a role for smooth processing or as a blanket gas. Nitrogen gas is supplied to the storage tank 100. Since the liquefaction temperature of nitrogen is lower than the liquefaction temperature of methane, which has the lowest liquefaction temperature among various hydrocarbons that can be included in the VOC, the content is different, but the VOC discharged from the crude oil storage tank 100 necessarily contains nitrogen.

However, in the fuel supply system according to the present embodiment, the VOC transferred from the crude oil storage tank 100 to the VOC collection tank 200 does not include a pretreatment device for removing impurities such as moisture or nitrogen.

That is, the VOC transferred from the crude oil storage tank 100 to the VOC collection tank 200 does not undergo a pretreatment process. VOCs transferred from the VOC collection tank 200 to the mixer 701 also do not undergo a pretreatment process.

The gaseous VOC collected in the VOC collection tank 200 is transferred to the mixer 701 without a phase change along the VOC supply line VL2 connecting the VOC collection tank 200 and the mixer 701.

In the VOC supply line VL2, a VOC valve CV capable of adjusting the flow rate of VOC transferred from the VOC collection tank 200 to the mixer 701 is installed.

The VOC valve CV may be controlled based on the composition of the VOC transferred from the VOC collection tank 200 to the mixer 701.

For example, when the nitrogen content of the VOC transferred from the VOC collection tank 200 to the mixer 701 exceeds a reference value, the opening amount of the VOC valve CV is controlled, and the mixer 701 from the VOC collection tank 200 ) To reduce the flow rate of VOC.

The reference value of the nitrogen content of the VOC transferred from the VOC collection tank 200 to the mixer 701 is the nitrogen content of the mixed fuel mixed in the mixer 701 is the nitrogen content required by the engine, for example, less than 20 mol% or It may be a value less than 30 mol%.

For example, if the heavy hydrocarbon content of the VOC transferred from the VOC collection tank 200 to the mixer 701, especially the heavy hydrocarbon content of 10 or more carbon atoms exceeds the reference value, the opening amount of the VOC valve (CV) is adjusted. , The flow rate of VOC supplied from the VOC collection tank 200 to the mixer 701 is reduced.

The reference value of the heavy hydrocarbons of the VOC transferred from the VOC collection tank 200 to the mixer 701 may be a value such that the mixed fuel mixed in the mixer 701 does not become multi-phase. For example, the reference value for preventing the mixed fuel from becoming polyphase may be that the concentration of heavy hydrocarbons containing 10 or more carbon atoms in the VOC is less than 1 mol%.

The engine 1000 of the present embodiment may be a two-stroke cycle engine. In addition, the engine 1000 of the present embodiment may be operated based on a diesel cycle in which high-pressure gaseous fuel is directly injected into the combustion chamber near the top dead center of the piston.

In addition, the pressure condition of the gaseous fuel required by the engine 1000 of the present embodiment may be about 200 bar to 420 bar, or about 250 bar to 380 bar, and preferably about 380 barg of high pressure gas fuel can be burned. have.

Further, the temperature condition of the gaseous fuel required by the engine 1000 of the present embodiment may be about 35°C to 45°C, and preferably about 45°C.

Further, the engine 1000 of the present embodiment may be a gas engine capable of using 100% ethane gas, 100% natural gas, a mixture of natural gas and VOC, and VOC as fuel.

For example, in this embodiment, the engine 1000 may be a MAN Electronic Gas Injection Ethane (ME-GIE) engine of MAN ES.

In addition, the engine 1000 of the present embodiment uses LNG as a main fuel, and uses a mixed fuel of LNG (or natural gas) and VOC or VOC as the fuel of the engine according to the amount of VOC generated.

That is, the ship of this embodiment is based on a natural gas fueled ship that normally uses LNG as a fuel.

LNG stored in the fuel storage tank 300 is pressurized by the fuel pump 400 and transferred to the high pressure pump 501 along the fuel supply line FL connecting the fuel pump 400 and the high pressure pump 501 .

The fuel pump 400 may pressurize the LNG stored in the fuel storage tank 300 to about 10 bar. However, it is not limited thereto.

The high pressure pump 501 compresses the LNG pressurized by the fuel pump 400 to a gas fuel pressure required by the engine 1000, that is, a high pressure of about 380 bar or higher in the present embodiment, and supplies it to the carburetor 601.

The LNG compressed at high pressure by the high pressure pump 501 is transferred to the carburetor 601 along the fuel supply line FL connecting the high pressure pump 501 and the carburetor 601.

In the carburetor 601, the high pressure required by the engine 1000 by the high pressure pump 501, that is, the LNG compressed to about 380 bar in this embodiment is vaporized into natural gas (gas state or supercritical state).

The natural gas vaporized in the carburetor 601 is supplied to the mixer 701 along the fuel supply line FL connecting the carburetor 601 and the mixer 701.

Between the fuel pump 400 and the high pressure pump 501, between the high pressure pump 501 and the carburetor 601, and between the carburetor 601 and the mixer 701, at least one of the fuel storage tank 300 to the mixer ( An LNG valve (not shown) that controls the flow rate of LNG transferred to 701 may be installed.

The LNG valve may be controlled according to the amount of fuel required by the engine 1000 and the heavy hydrocarbon or nitrogen content of the VOC transferred from the VOC collection tank 200 to the mixer 701.

The mixer 701 of this embodiment may be an eductor using the Bernoulli effect. The eductor 701 uses the high pressure required by the engine 1000, that is, the high pressure natural gas compressed to about 380 bar in this embodiment as a driving fluid, without using external power such as electric power. VOCs transferred from the VOC collection tank 200 to the eductor 701 can be sucked and mixed without power. In the mixer 701, high-pressure natural gas and VOC are mixed in a single phase and diffusely sprayed.

When the eductor is used as the mixer 701 as in this embodiment, the fluid diffused and injected into the eductor promotes mixing while forming a curved vortex, so that natural gas and VOC are easily and uniformly mixed without using power. I can make it.

The mixed fuel in which natural gas and VOC are mixed in the eductor 701 is supplied as fuel of the engine 1000 along the mixed fuel supply line ML1 connecting the eductor 701 and the engine 1000.

Next, referring to FIG. 2, a method of supplying fuel to a fuel supply system for a crude oil carrier according to a second embodiment of the present invention will be described. This embodiment is a modification of the above-described first embodiment, and unlike the first embodiment in which the mixer 701 is installed downstream of the high pressure pump 501, in this embodiment, the mixer 702 is a high pressure pump 502 There is a difference in that it is installed upstream of ). Hereinafter, differences will be mainly described, and detailed descriptions of the same members will be omitted. Even if a specific reference or description is omitted, the same member may be applied in the same manner as in the first embodiment.

A fuel supply system for a crude oil carrier according to the present embodiment includes: one or more crude oil storage tanks 100 for storing crude oil; A VOC collection tank 200 for collecting volatile organic compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 without phase change; A fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as fuel for the engine 1000 of the ship; A fuel pump 400 for pressurizing the LNG stored in the fuel storage tank 300 and discharging it from the fuel storage tank 300 to the outside; A mixer 702 for mixing LNG and VOC by suctioning gaseous VOC transferred from the VOC collection tank 200 by using LNG in a liquid state pressurized by the fuel pump 400 as a driving fluid; A high-pressure pump 502 for compressing the liquid mixed fuel mixed in the mixer 702 to a pressure range required by the engine 1000; A vaporizer 602 for vaporizing the mixed fuel compressed by the high pressure pump 502; And an engine that uses natural gas vaporized using the carburetor 602 from the LNG stored in the fuel storage tank 300, the VOC collected in the VOC collection tank 200, or the mixed fuel vaporized by the carburetor 602 as fuel. (1000); includes.

The VOC collection line (VL1) connects the crude oil storage tank 100 and the VOC collection tank 200, and the VOC discharged from the crude oil storage tank 100 is the VOC collection tank 200 along the VOC collection line (VL1). Is transferred to.

VOCs generated by evaporation of crude oil in the crude oil storage tank 100 are in a gaseous state, and are transferred along the VOC collection line VL1 in a gaseous state, and stored in a gaseous state in the VOC collection tank 200.

Likewise, VOCs stored in the VOC collection tank 200 in this embodiment are transferred from the crude oil storage tank 100 to the VOC storage tank 200 while being stored in the VOC storage tank 200, VOC storage While being transferred from the tank 200 to the mixer 702 along the VOC supply line VL2, no phase change occurs.

In addition, in the fuel supply system according to the present embodiment, the VOC transferred from the crude oil storage tank 100 to the VOC collection tank 200 does not include a pretreatment device for removing impurities such as moisture or nitrogen.

The gaseous VOC collected in the VOC collection tank 200 is transferred to the mixer 702 without a phase change along the VOC supply line VL2 connecting the VOC collection tank 200 and the mixer 702.

The VOC supply line (VL2) is provided with a VOC valve (CV) capable of controlling the flow rate of VOC transferred from the VOC collection tank 200 to the mixer 702.

The VOC valve CV may be controlled based on the composition of the VOC transferred from the VOC collection tank 200 to the mixer 702. The control method can be applied in the same manner as in the first embodiment.

The engine 1000 of the present embodiment is a two-stroke cycle engine and may be operated based on a diesel cycle.

The LNG stored in the fuel storage tank 300 is pressurized by the fuel pump 400 and transferred to the mixer 702 along the fuel supply line FL connecting the fuel pump 400 and the mixer 702.

The mixer 702 of this embodiment may be an eductor using the Bernoulli effect. The eductor 702 may suck gaseous VOC transferred from the VOC collection tank 200 to the eductor 702 by using LNG in a liquid state pressurized by the fuel pump 400 as a working fluid. .

LNG pressurized by the fuel pump 400 may be about 10 barg or more. However, it is not limited thereto. The fuel pump 400 compresses LNG to a pressure sufficient to condense VOCs in the mixer 702.

In the mixer 702, LNG and VOC are mixed in a single phase and diffusely sprayed. The gaseous VOC is diffusely sprayed into compressed liquid LNG, condensed, and mixed with LNG in a liquid state.

The mixed fuel in which LNG and VOC are mixed in the eductor 702 is transferred to the high pressure pump 502 along the mixed fuel supply line ML2 connecting the eductor 702 and the high pressure pump 502.

The high-pressure pump 502 compresses the mixed fuel of LNG and VOC mixed in the mixer 702 to a gas fuel pressure required by the engine 1000, that is, a high pressure of about 380 bar or more, and supplies it to the carburetor 602.

The mixed fuel compressed at high pressure by the high pressure pump 502 is transferred to the carburetor 602 along the mixed fuel supply line ML2 connecting the high pressure pump 502 and the carburetor 602.

In the carburetor 602, the high pressure required by the engine 1000 by the high pressure pump 502, that is, the mixed fuel compressed to about 380 bar in this embodiment is vaporized in a gaseous state or a supercritical state.

The mixed fuel gas vaporized in the carburetor 602 is supplied to the engine 1000 along the mixed fuel supply line ML2 connecting the carburetor 602 and the engine 1000.

An LNG valve (not shown) may be installed between the fuel pump 400 and the mixer 702 to control the flow rate of LNG transferred from the fuel storage tank 300 to the mixer 702.

Next, referring to FIG. 3, a method of supplying fuel to a fuel supply system for a crude oil carrier according to a third embodiment of the present invention will be described. This embodiment is a modified example of the second embodiment described above, and unlike the second embodiment in which an eductor is provided as the mixer 702, a condenser is provided as the mixer 900, and a VOC compressor 800 is further included. There is a difference in that. Hereinafter, differences will be mainly described, and detailed descriptions of the same members will be omitted. Even if specific reference or description is omitted, the same member may be applied in the same manner as in the second embodiment described above.

A fuel supply system for a crude oil carrier according to the present embodiment includes: one or more crude oil storage tanks 100 for storing crude oil; A VOC collection tank 200 for collecting volatile organic compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 without phase change; A fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as fuel for the engine 1000 of the ship; A fuel pump 400 for pressurizing the LNG stored in the fuel storage tank 300 and discharging the LNG from the fuel storage tank 300 to the outside; A mixer 900 for mixing the LNG pressurized by the fuel pump 400 and the VOC transferred from the VOC collection tank 200; A VOC compressor 800 for compressing VOCs to be supplied from the VOC collection tank 200 to the mixer 900; A high pressure pump 503 for compressing the mixed fuel in a liquid state mixed in the mixer 900 to a pressure range required by the engine 1000; A vaporizer 603 for vaporizing the mixed fuel compressed by the high pressure pump 503; And an engine that uses natural gas vaporized using the vaporizer 603 of LNG stored in the fuel storage tank 300, VOC collected in the VOC collection tank 200, or mixed fuel vaporized by the vaporizer 603 as fuel. (1000); includes.

The VOC collection line (VL1) connects the crude oil storage tank 100 and the VOC collection tank 200, and the VOC discharged from the crude oil storage tank 100 is the VOC collection tank 200 along the VOC collection line (VL1). Is transferred to.

VOCs generated by evaporation of crude oil in the crude oil storage tank 100 are in a gaseous state, and are transferred along the VOC collection line VL1 in a gaseous state, and stored in a gaseous state in the VOC collection tank 200.

Likewise, in this embodiment, the VOC stored in the VOC collection tank 200 is transferred from the crude oil storage tank 100 to the VOC storage tank 200, while being stored in the VOC storage tank 200, the mixer ( 900), no phase change occurs.

In addition, the fuel supply system according to the present embodiment, VOC transferred from the crude oil storage tank 100 to the VOC collection tank 200 and impurities such as moisture or nitrogen transferred from the VOC collection tank 200 to the mixer 900 Does not include a pretreatment device to remove.

The gaseous VOC collected in the VOC collection tank 200 is transferred to the VOC compressor 800 along the VOC supply line VL3 connecting the VOC collection tank 200 and the VOC compressor 800.

The VOC supply line (VL3) is provided with a VOC valve (CV) capable of adjusting the flow rate of VOC transferred from the VOC collection tank 200 to the VOC compressor 800.

The VOC valve (CV) may be controlled based on the composition of the VOC transferred from the VOC collection tank 200 to the mixer 900. The control method can be applied in the same manner as in the first embodiment described above.

The engine 1000 of the present embodiment is a two-stroke cycle engine and may be operated based on a diesel cycle.

The LNG stored in the fuel storage tank 300 is pressurized by the fuel pump 400 and transferred to the mixer 900 along a fuel supply line FL connecting the fuel pump 400 and the mixer 900.

The mixer 900 of the present embodiment may be a condensor for condensing compressed VOC by mixing LNG pressurized by the fuel pump 400 and VOC compressed by the VOC compressor 800.

LNG pressurized by the fuel pump 400 may be about 10 barg or more. However, it is not limited thereto. The fuel pump 400 compresses LNG to a pressure sufficient to condense the VOC in the mixer 900.

In addition, the VOC compressor 800 may compress VOC at a pressure substantially equal to the pressure at which the compression pump 400 compresses LNG.

The mixed fuel in a liquid state in which LNG and VOC are mixed in the mixer 900 is transferred to the high pressure pump 503 along the mixed fuel supply line ML3 connecting the mixer 900 and the high pressure pump 503.

The high-pressure pump 503 compresses the mixed fuel of LNG and VOC mixed in the mixer 900 to a gas fuel pressure required by the engine 1000, that is, a high pressure of about 380 bar or higher, and supplies it to the carburetor 603.

The mixed fuel compressed at high pressure by the high pressure pump 503 is transferred to the carburetor 603 along the mixed fuel supply line ML3 connecting the high pressure pump 503 and the carburetor 603.

In the carburetor 603, the high pressure required by the engine 1000 by the high pressure pump 503, that is, the mixed fuel compressed to about 380 bar in this embodiment is vaporized in a gaseous state or a supercritical state.

The mixed fuel gas vaporized in the carburetor 603 is supplied to the engine 1000 along the mixed fuel supply line ML3 connecting the carburetor 603 and the engine 1000.

An LNG valve (not shown) may be installed between the fuel pump 400 and the mixer 900 to control the flow rate of LNG transferred from the fuel storage tank 300 to the mixer 900.

In the conventional VOC treatment system, after liquefying VOC, including a refrigeration cycle, it is stored in a storage tank, or liquefied VOC, that is, LVOC, is vaporized and supplied to some engines that can use the VOC as fuel. Since LVOC is a liquefied VOC, it contains a relatively high concentration of heavy hydrocarbons than before liquefaction, and in particular, it mainly contains heavy hydrocarbons with a large carbon number.

On the other hand, in the process of liquefying VOC, a gas with a very low boiling point that is not liquefied, for example, SVOC containing low-carbon hydrocarbons such as nitrogen, methane or ethane, was separately separated and used as fuel for a boiler or gas turbine.

Therefore, the conventional VOC treatment system is expensive in that power consumption is very high, occupies a lot of space, and is composed of an expensive package. In addition, the components of the VOC depend on the residence time in the crude oil storage tank, and the longer the residence time, the higher the content of the heavy hydrocarbon component, and thus there is a problem that fuel supply is not smooth.

In addition, since most engines cannot burn SVOC with high nitrogen content as well as LVOC with high heavy hydrocarbon content, a method of reforming VOC with methane and supplying it as fuel has also been proposed. However, since the reforming reaction itself requires a large amount of heat source, and the reforming reaction system equipment has a large volume and safety is not guaranteed to be applied to the ship, there was a lot of burden to install it on the ship.

However, according to the present invention, by omitting the VOC pretreatment process, the VOC reforming process, and the VOC liquefaction process, and supplying the VOC and LNG as fuel to the engine, power consumption, cost or physical space burden according to the installation space Can be significantly reduced. In addition, it is eco-friendly because harmful VOCs can be recovered and used as fuel without releasing them to the atmosphere.

As described above, the embodiments according to the present invention have been looked at, and the fact that the present invention can be embodied in other specific forms without departing from its spirit or scope in addition to the above-described embodiments is understood by those of ordinary skill in the art. It is self-evident to Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive, and accordingly, the present invention is not limited to the above description, and may be modified within the scope of the appended claims and equivalents thereof.

100: crude oil storage tank
200: VOC collection tank
300: fuel storage tank
400: fuel pump
501, 502. 503: high pressure pump
601. 602, 603: carburetor
701, 702, 900: mixer
800: VOC compressor
1000: engine
VL1: VOC collection line
VL2, VL3: VOC supply line
FL: fuel supply line
ML1, ML2, ML3: Mixed fuel supply line

Claims (10)

A VOC collection tank that collects gaseous Volatile Organic Compounds (VOCs) discharged from the crude oil storage tank without phase change;
A fuel storage tank that stores LNG (Liquefied Natural Gas) to be used as fuel for the engine;
A fuel pump for pressurizing and discharging the LNG stored in the fuel storage tank;
A VOC compressor for compressing VOC discharged from the VOC collection tank to a pressure equal to a pressure at which the fuel pump pressurizes LNG; And
Including; a mixer for mixing the liquid LNG pressurized by the fuel pump and the gaseous VOC compressed by the VOC compressor; and
The engine is a two-stroke diesel cycle engine,
A mixed fuel supply line connecting the mixer and the engine to transfer the mixed fuel mixed in the mixer to the engine; And
A VOC supply line for connecting the VOC collection tank and the mixer to transfer the unmodified VOC from the VOC collection tank to the mixer; further comprising, a fuel supply system for a crude oil carrier. The method according to claim 1,
The mixed fuel of LNG and VOC mixed in the mixer is in a liquid state,
A high pressure pump for compressing the liquid mixed fuel to a high pressure required by the engine; And
A vaporizer for vaporizing the mixed fuel compressed by the high pressure pump; further comprises,
A fuel supply system for a crude oil carrier, wherein the mixed fuel in a gaseous state vaporized in the carburetor is supplied as fuel of the engine through the mixed fuel supply line. The method according to claim 1,
A VOC valve installed on the VOC supply line and controlling an opening amount according to the nitrogen content of VOC supplied from the VOC collection tank to the mixer; further comprising, a fuel supply system for a crude oil carrier. The method of claim 3,
A control unit for controlling the opening amount of the VOC valve so that the nitrogen content of the mixed fuel mixed in the mixer is less than 30 mol%; further comprising, a fuel supply system for a crude oil carrier. The method according to claim 1,
The engine is a gas engine capable of using 100% ethane gas, 100% natural gas, a mixture of natural gas and VOC, and VOC as fuel, a fuel supply system of a crude oil carrier. The method according to claim 2 or 5,
The high pressure pump compresses the mixed fuel to 200 bar to 420 bar, a fuel supply system of a crude oil carrier. The method according to claim 1,
A VOC collection line connecting the crude oil storage tank and the VOC collection tank and transferring VOC containing nitrogen and heavy hydrocarbon components from the crude oil storage tank to the VOC collection tank; further comprising,
The VOC is transferred from the crude oil storage tank to a VOC collection tank and from the VOC collection tank to a mixer without a process of removing moisture and nitrogen and a pretreatment process of reforming heavy hydrocarbons into methane.The fuel supply system of a crude oil carrier. The gaseous VOC (Volatile Organic Compounds) discharged from the crude oil storage tank is collected and stored in a gaseous state without phase change,
Each of the LNG to be used as fuel for the engine and the gaseous VOC are compressed at the same pressure,
Mixing the compressed liquid LNG and the compressed gaseous VOC,
A fuel supply method of a crude oil carrier for supplying a mixed fuel of the LNG and VOC to a two-stroke diesel cycle engine. The method of claim 8,
The mixed fuel is further compressed to the high pressure required by the engine,
Vaporize the mixed fuel compressed at the high pressure,
The fuel supply method of a crude oil carrier supplying the gaseous mixed fuel to the engine. The method of claim 8,
A method of supplying fuel for a crude oil carrier by adjusting the flow rate of gaseous VOC to be mixed with the compressed LNG so that the nitrogen content of the mixed fuel is less than 30 mol%.

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