KR102276367B1 - Fuel Gas Supply System and Method for Crude Oil Eco-carrier - Google Patents

Abstract

The present invention relates to a fuel supply system fuel supply method capable of using volatile organic compounds generated in a crude oil storage tank of a crude oil carrier using liquefied natural gas as a fuel as a fuel for an engine.
A fuel supply system for a crude oil carrier according to the present invention includes: a VOC collection tank that collects VOC (Volatile Organic Compounds) in a gaseous state discharged from a crude oil storage tank as it is without phase change; a fuel storage tank for storing LNG (Liquefied Natural Gas) to be used as an engine fuel; 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 to the same pressure as the pressure at which the fuel pump pressurizes the LNG; and a mixer for mixing the liquid LNG pressurized by the fuel pump and the gaseous VOC compressed by the VOC compressor, wherein the engine is a two-stroke diesel cycle engine, and connects the mixer and the engine to , a mixed fuel supply line for transferring the mixed fuel mixed in the mixer to the engine; and a VOC supply line connecting the VOC collection tank and the mixer to transfer the unmodified VOC from the VOC collection tank to the mixer.

Description

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

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

A plurality of crude oil storage tanks (cargo tanks) that can store crude oil are installed on the crude oil carrier. In the crude oil storage tank, the stored crude oil is evaporated to generate volatile organic compounds (VOCs). In order to safely maintain the pressure of the crude oil storage tank, the VOC generated in the crude oil storage tank must be discharged to the outside.

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

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

Due to the harmfulness of VOCs, the International Maritime Organization and others are regulating the loading and unloading of VOCs in some ports. In addition, the emission of VOCs to the atmosphere results in the loss of that much effective material, so rather than releasing VOCs into the atmosphere, it is necessary to find a way to recover them and effectively treat them.

VOC reduction technology that reduces the amount of VOC generated during cargo loading and VOC recovery technology (VOC recovery technology) that recovers and treats the generated VOC without discharging it into the atmosphere recovery technology) is being applied with a solid line.

VOC generation reduction technology, when loading cargo into a crude oil storage tank, reduces the generation of negative pressure in the crude oil storage tank, and a technology to control the pressure of the tank below the vapor pressure of crude oil (vapor pressure) is representative.

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

On the other hand, since VOCs generated from crude oil carriers do not meet the methane number of a gas engine due to a high content of heavy hydrocarbons, the VOC must be reformed into methane, which is a light hydrocarbon, using a reformer.

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

The present invention provides an improved fuel supply method for a fuel supply system of a crude oil carrier so that VOC generated from a ship can be efficiently and efficiently supplied as a fuel for an engine without discharging to the atmosphere at a more convenient and low cost while using LNG as a fuel would like to provide

According to one aspect of the present invention for achieving the above object, the VOC collection tank for collecting gaseous VOC (Volatile Organic Compounds) discharged from the crude oil storage tank as it is without changing the phase; a fuel storage tank for storing LNG (Liquefied Natural Gas) to be used as an engine fuel; 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 to the same pressure as the pressure at which the fuel pump pressurizes the LNG; and a mixer for mixing the liquid LNG pressurized by the fuel pump and the gaseous VOC compressed by the VOC compressor, wherein the engine is a two-stroke diesel cycle engine, and by connecting the mixer and the engine , a mixed fuel supply line for transferring the mixed fuel mixed in the mixer to the engine; and a VOC supply line that connects the VOC collection tank and the mixer to transfer the unreformed VOC from the VOC collection tank to the mixer; further comprising, a fuel supply system for a crude oil carrier is provided.

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 gaseous mixed fuel vaporized in the carburetor may be supplied as the fuel of the engine through the mixed fuel supply line.

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

Preferably, the 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 may 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 VOCs containing nitrogen and heavy hydrocarbons from the crude oil storage tank to the VOC collection tank; further comprising, the VOCs, 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 VOC (Volatile Organic Compounds) discharged from the crude oil storage tank is collected and stored in the gaseous state without changing the phase, and LNG to be used as the fuel of the engine. and the VOC in the gaseous state are compressed respectively, but compressed to the same pressure, the compressed liquid LNG and the compressed gaseous VOC are mixed, and the mixed fuel obtained by mixing the LNG and the VOC is used as a two-stroke diesel A method of refueling a crude oil carrier, which feeds a cycle engine, is provided.

Preferably, the mixed fuel may be further compressed to a high pressure required by the engine, the mixed fuel compressed to the high pressure may be vaporized, and the vaporized mixed fuel in a gaseous state 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 system fuel supply method of a 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 recyclability 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 are not required, installation costs, area and energy costs can be reduced by omitting additional equipment.

In addition, it is possible to recover VOC without using electric power, thereby reducing the power consumption of the vessel.

By supplying the recovered VOC as fuel for the engine, it can be treated in an environmentally friendly manner without emitting harmful VOCs into the atmosphere.

1 is a schematic diagram illustrating a fuel supply system of a crude oil carrier according to a first embodiment of the present invention.
2 is a schematic diagram illustrating a fuel supply system of a crude oil carrier according to a second embodiment of the present invention.
Figure 3 is a schematic diagram illustrating a fuel supply system of 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 objects 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 the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, in adding reference signs to the elements of each drawing, it should be noted that only the same elements are indicated by the same reference signs as possible even if they are indicated on different drawings. In addition, the following examples may be modified in various other forms, and the scope of the present invention is not limited to the following examples.

In an embodiment of the present invention to be described later, 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). ), may be liquefied ethylene gas.

However, in the embodiments to be described later, an example in which LNG, which is a representative liquefied gas, is applied will be described. LNG has methane as its main component, and includes ethane, propane, butane, and the like, and its composition may vary depending on the production area.

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

In addition, in the embodiment 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 for producing crude oil at sea Floating, Production, Storage and Offloading Unit (FPSO), a product carrier that transports petroleum products that transports produced crude oil, and a Floating and Offloading Unit (FSU) that can store the produced crude oil. Storage Unit), etc., are provided, and a significant amount of VOC is generated, which poses a potential environmental risk, and can be applied to all ships or floating structures on the sea that need to be fueled by an engine.

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

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

A fuel supply system of a crude oil carrier according to a first embodiment of the present invention, one or more crude oil storage tanks for storing crude oil (cargo tank, 100); a VOC collection tank 200 that collects volatile organic compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 as it is without phase change; a fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as a 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 to 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 vaporizer 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 the fuel of the engine 1000 a mixer 701; and natural gas obtained by vaporizing LNG stored in the fuel storage tank 300 using the vaporizer 601, VOC collected in the VOC collection tank 200, or a mixed fuel of natural gas and VOC mixed by the mixer 701. The engine 1000 used as fuel; 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 a 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 transported along the VOC collection line VL1 as it is in the gaseous state, and is stored in the gaseous state in the VOC collection tank 200 .

That is, 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 stored in the VOC storage tank 200 , and VOC storage No phase change occurs 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 smaller capacity than one crude oil storage tank 100 .

VOC discharged from the crude oil storage tank 100 includes impurities such as moisture or nitrogen as well as hydrocarbon components of various carbon numbers.

Although the composition of VOC discharged from the crude oil storage tank 100 varies depending on the composition of crude oil, propane and butane (especially, normal butane) are the main components, and in addition, ethane, isobutane, normal pentane and isopentane, hexane , 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 , a role for making a smooth process or a role of a blanket gas as a role of crude oil 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 may be included in the VOC, the VOC discharged from the crude oil storage tank 100 necessarily contains nitrogen although the content is different.

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

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

The gaseous VOCs collected in the VOC collection tank 200 are 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 VOC transferred from the VOC collection tank 200 to the mixer 701 .

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

The reference value of the nitrogen content of the VOC transferred from the VOC collection tank 200 to the mixer 701 is that 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 The value may be less than 30 mol%.

For example, when the heavy hydrocarbon content of the VOC transferred from the VOC collection tank 200 to the mixer 701, particularly the heavy hydrocarbon content with 10 or more carbon atoms, exceeds the reference value, by adjusting the opening degree of the VOC valve (CV) , the flow rate of VOC supplied from the VOC collection tank 200 to the mixer 701 is reduced.

The reference value of heavy hydrocarbons of VOC transferred from the VOC collection tank 200 to the mixer 701 may be a value that prevents the mixed fuel mixed in the mixer 701 from becoming multi-phase. For example, the reference value for preventing the mixed fuel from becoming polyphase may be that the concentration of heavy hydrocarbons having 10 or more carbon atoms included in the VOC is less than 1 mol%.

The engine 1000 of this embodiment may be a 2-stroke cycle engine. In addition, the engine 1000 of the present embodiment may be operated based on a diesel cycle in which high-pressure gas fuel is directly injected into the combustion chamber near the top dead center of the piston.

In addition, the pressure condition of the gas fuel required by the engine 1000 of this embodiment may be about 200 bar to 420 bar, or about 250 bar to 380 bar, and preferably, it is possible to burn a high-pressure gas fuel of about 380 barg. have.

In addition, the temperature condition of the gas fuel required by the engine 1000 of this embodiment may be about 35 °C to 45 °C, preferably about 45 °C.

Also, the engine 1000 of this 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 the present embodiment, the engine 1000 may be a MAN Electronic Gas Injection Ethane (ME-GIE) engine manufactured by MAN ES.

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

That is, the ship of this embodiment is based on a natural gas fueled ship using LNG as a fuel in normal times.

The 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, the present invention is not limited thereto.

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

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

In the vaporizer 601, the high pressure required by the engine 1000 by the high-pressure pump 501, that is, 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 vaporizer 601 is supplied to the mixer 701 along the fuel supply line FL connecting the vaporizer 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 in any one or more of the fuel storage tank 300 from the mixer ( An LNG valve (not shown) for controlling 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, as a driving fluid, high pressure required by the engine 1000, that is, natural gas compressed to about 380 bar in this embodiment, without using external power such as electric power. The VOC transferred from the VOC collection tank 200 to the eductor 701 without power may be sucked and mixed. In the mixer 701, high-pressure natural gas and VOC are mixed into a single phase and diffusely sprayed.

When the eductor is used as the mixer 701 as in this embodiment, the fluid diffused and sprayed into the eductor forms a curved vortex and promotes mixing, so natural gas and VOC can be easily and uniformly mixed without using power. can do it

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

Next, with reference to FIG. 2, a method for supplying fuel to a fuel supply system of 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. 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 the high-pressure pump 502. ) is different 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 specific mention or description is omitted, the same members may be applied in the same manner as in the above-described first embodiment.

The fuel supply system of the crude oil carrier according to this embodiment, one or more crude oil storage tanks for storing crude oil (cargo tank, 100); a VOC collection tank 200 that collects volatile organic compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 as it is without phase change; a fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as a 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 sucking in the gaseous VOC transferred from the VOC collection tank 200 using the liquid LNG pressurized by the fuel pump 400 as a driving fluid; a high-pressure pump 502 for compressing the mixed fuel in the liquid state 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 natural gas obtained by vaporizing LNG stored in the fuel storage tank 300 using the vaporizer 602, VOC captured in the VOC collection tank 200, or an engine using a mixed fuel vaporized by the vaporizer 602 as fuel. (1000);

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 a VOC collection tank 200 along the VOC collection line (VL1). is transferred to

VOC generated by evaporating crude oil in the crude oil storage tank 100 is in a gaseous state, and is transferred along the VOC collection line VL1 in a gaseous state, and is stored in a gaseous state in the VOC collecting tank 200 .

Similarly, 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 stored in the VOC storage tank 200, VOC storage No phase change occurs while being transferred from the tank 200 to the mixer 702 along the VOC supply line VL2.

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

The gaseous VOCs collected in the VOC collection tank 200 are 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 .

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 702; is installed.

The VOC valve CV may be controlled based on the composition of 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 this embodiment is a 2-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 use the liquid LNG pressurized by the fuel pump 400 as a working fluid to suck in the gaseous VOC transferred from the VOC collection tank 200 to the eductor 702 . .

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

In the mixer 702, LNG and VOC are mixed into a single phase and diffusely sprayed. VOC in gaseous state is diffusely sprayed into compressed liquid LNG, condensed, and mixed with LNG in 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 the 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 to a 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 vaporizer 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 into 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) for controlling the flow rate of LNG transferred from the fuel storage tank 300 to the mixer 702 may be installed between the fuel pump 400 and the mixer 702 .

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

The fuel supply system of the crude oil carrier according to this embodiment, one or more crude oil storage tanks for storing crude oil (cargo tank, 100); a VOC collection tank 200 that collects Volatile Organic Compounds (VOC) generated by evaporation of crude oil in the crude oil storage tank 100 as it is without phase change; a fuel storage tank 300 for storing liquefied natural gas (LNG) to be used as a fuel for the engine 1000 of the ship; a fuel pump 400 that pressurizes the LNG stored in the fuel storage tank 300 and discharges it 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 VOC to be supplied from the VOC collection tank 200 to the mixer 900; a high-pressure pump (503) for compressing the mixed fuel in the 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 natural gas obtained by vaporizing LNG stored in the fuel storage tank 300 using the vaporizer 603, VOC captured in the VOC collection tank 200, or an engine using a mixed fuel vaporized by the vaporizer 603 as fuel. (1000);

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 a VOC collection tank 200 along the VOC collection line (VL1). is transferred to

VOC generated by evaporating crude oil in the crude oil storage tank 100 is in a gaseous state, and is transferred along the VOC collection line VL1 in a gaseous state, and is stored in a gaseous state in the VOC collecting tank 200 .

Similarly, 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 it is stored in the VOC storage tank 200, the mixer ( 900), no phase change occurs.

In addition, the fuel supply system according to this 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. It does not include a pretreatment device to remove it.

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

A VOC valve (CV) capable of controlling the flow rate of VOC transferred from the VOC collection tank 200 to the VOC compressor 800 is installed in the VOC supply line VL3.

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 above-described first embodiment.

The engine 1000 of this embodiment is a 2-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 the fuel supply line FL connecting the fuel pump 400 and the mixer 900 .

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

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

In addition, the VOC compressor 800 may compress the VOC to a pressure substantially the same as the pressure at which the compression pump 400 compresses the 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 more, and supplies it to the carburetor 603 .

The mixed fuel compressed to a 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 vaporizer 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 into 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) for controlling the flow rate of LNG transferred from the fuel storage tank 300 to the mixer 900 may be installed between the fuel pump 400 and the mixer 900 .

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

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

Therefore, the conventional VOC treatment system has a very high power consumption for a refrigeration cycle and the like, occupies a lot of space, and is expensive in that it is composed of an expensive package. In addition, the composition of VOC varies depending on the residence time in the crude oil storage tank, and the longer the residence time, the higher the content of heavy hydrocarbon components, so there is a problem that the 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 into methane and supplying it as fuel has also been proposed. However, the reforming reaction itself requires a large amount of heat source, and since the reforming reaction system facility has a large volume and safety is not guaranteed to be applied to the vessel, there is a lot of burden in installing it on the vessel.

However, according to the present invention, the pretreatment process of VOC, reforming process of VOC, and liquefaction process of VOC are omitted, and VOC and LNG are mixed and supplied as fuel for the engine, so power consumption and cost or physical space burden according to installation space can be significantly reduced. In addition, it is eco-friendly because it can be used as fuel by collecting all harmful VOCs without releasing them into the atmosphere.

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

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 VOC (Volatile Organic Compounds) in gaseous state discharged from the crude oil storage tank as it is without changing the phase;
a fuel storage tank for storing LNG (Liquefied Natural Gas) to be used as an engine fuel;
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 to the same pressure as the pressure at which the fuel pump pressurizes the LNG; and
A mixer for mixing the liquid LNG pressurized by the fuel pump and the gaseous VOC compressed by the VOC compressor;
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
It further includes; a VOC supply line that connects the VOC collection tank and the mixer to transfer the unmodified VOC from the VOC collection tank to the mixer.
The gaseous VOC discharged from the crude oil storage tank is supplied to the mixer without phase change, and the mixed fuel in which LNG and VOC are mixed in the mixer is in a liquid state, a fuel supply system for a crude oil carrier. The method according to claim 1,
a high-pressure pump for compressing the mixed fuel in the liquid state to a high pressure required by the engine; and
It further includes; a vaporizer for vaporizing the mixed fuel compressed by the high-pressure pump,
The gaseous mixed fuel vaporized in the carburetor is supplied as the fuel of the engine through the mixed fuel supply line, a fuel supply system for a crude oil carrier. The method according to claim 1,
The VOC valve is installed in the VOC supply line, and the opening degree is controlled according to the nitrogen content of the VOC supplied from the VOC collection tank to the mixer; further comprising a fuel supply system for a crude oil carrier. 4. The method according to claim 3,
A fuel supply system for a crude oil carrier, further comprising a; a control unit for controlling the opening degree of the VOC valve so that the nitrogen content of the mixed fuel mixed in the mixer is less than 30 mol%. 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 for a crude oil carrier. 3. The method according to claim 2,
The high-pressure pump, the fuel supply system of the crude oil carrier for compressing the mixed fuel to 200 bar to 420 bar. The method according to claim 1,
A VOC collection line connecting the crude oil storage tank and the VOC collection tank, and transferring VOCs containing nitrogen and heavy hydrocarbons from the crude oil storage tank to the VOC collection tank; further comprising,
The VOC is 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, 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 the gaseous state without changing the phase,
LNG to be used as fuel for the engine and VOC in the gaseous state are compressed respectively, but compressed to the same pressure,
Mixing the compressed liquid LNG and the compressed gaseous VOC in a mixer,
The mixed fuel of the LNG and VOC is supplied to a two-stroke diesel cycle engine,
The gaseous VOC discharged from the crude oil storage tank is supplied to the mixer without a phase change, and the mixed fuel of LNG and VOC mixed in the mixer is in a liquid state, a fuel supply method for a crude oil carrier. 9. The method of claim 8,
The mixed fuel is further compressed to the high pressure required by the engine,
Vaporizing the mixed fuel compressed at high pressure,
Supplying the mixed fuel of the vaporized gaseous state to the engine, the fuel supply method of the crude oil carrier. 9. The method of claim 8,
A fuel supply method of a crude oil carrier for controlling the flow rate of VOC in a gaseous state 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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