WO2023066462A1 - Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier - Google Patents

Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier Download PDF

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Publication number
WO2023066462A1
WO2023066462A1 PCT/EP2021/078912 EP2021078912W WO2023066462A1 WO 2023066462 A1 WO2023066462 A1 WO 2023066462A1 EP 2021078912 W EP2021078912 W EP 2021078912W WO 2023066462 A1 WO2023066462 A1 WO 2023066462A1
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WIPO (PCT)
Prior art keywords
steam
pressure
low
lng carrier
water
Prior art date
Application number
PCT/EP2021/078912
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English (en)
Inventor
Francisco Javier SÁEZ PARGA
Original Assignee
Gas Shipping Advisors, S.L.
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Filing date
Publication date
Application filed by Gas Shipping Advisors, S.L. filed Critical Gas Shipping Advisors, S.L.
Priority to EP21798323.8A priority Critical patent/EP4200521A1/fr
Priority to PCT/EP2021/078912 priority patent/WO2023066462A1/fr
Publication of WO2023066462A1 publication Critical patent/WO2023066462A1/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
    • F22B1/1807—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines using the exhaust gases of combustion engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B83/00—Rebuilding or retrofitting vessels, e.g. retrofitting ballast water treatment systems
    • B63B83/30—Rebuilding or retrofitting vessels, e.g. retrofitting ballast water treatment systems for improving energy efficiency, e.g. by improving hydrodynamics or by upgrading the power plant
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/02—Use of propulsion power plant or units on vessels the vessels being steam-driven
    • B63H21/06—Use of propulsion power plant or units on vessels the vessels being steam-driven relating to steam turbines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/02—Use of propulsion power plant or units on vessels the vessels being steam-driven
    • B63H21/08—Use of propulsion power plant or units on vessels the vessels being steam-driven relating to steam boilers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K13/00—General layout or general methods of operation of complete plants
    • F01K13/006—Auxiliaries or details not otherwise provided for
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K15/00—Adaptations of plants for special use
    • F01K15/02—Adaptations of plants for special use for driving vehicles, e.g. locomotives
    • F01K15/04—Adaptations of plants for special use for driving vehicles, e.g. locomotives the vehicles being waterborne vessels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/065—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle the combustion taking place in an internal combustion piston engine, e.g. a diesel engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/10—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with exhaust fluid of one cycle heating the fluid in another cycle
    • F01K23/103—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with exhaust fluid of one cycle heating the fluid in another cycle with afterburner in exhaust boiler
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K27/00—Plants for converting heat or fluid energy into mechanical energy, not otherwise provided for
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating
    • F01K7/06—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating the engines being of multiple-inlet-pressure type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating
    • F01K7/34—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating the engines being of extraction or non-condensing type; Use of steam for feed-water heating
    • F01K7/38—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating the engines being of extraction or non-condensing type; Use of steam for feed-water heating the engines being of turbine type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
    • F22B1/1807—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines using the exhaust gases of combustion engines
    • F22B1/1815—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines using the exhaust gases of combustion engines using the exhaust gases of gas-turbines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B31/00—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
    • F22D7/00—Auxiliary devices for promoting water circulation
    • F22D7/12—Control devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
    • B63H2021/202—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
    • B63H2021/202—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type
    • B63H2021/207—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type the second power unit being a gas turbine
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63J—AUXILIARIES ON VESSELS
    • B63J99/00—Subject matter not provided for in other groups of this subclass
    • B63J2099/001—Burning of transported goods, e.g. fuel, boil-off or refuse
    • B63J2099/003—Burning of transported goods, e.g. fuel, boil-off or refuse of cargo oil or fuel, or of boil-off gases, e.g. for propulsive purposes

Definitions

  • the object of the invention refers to a method for conversion of LNG (Liquefied Natural Gas) carriers steam turbine propulsion or hybrid steam and Diesel or hybrid steam and gas turbine propulsion installations.
  • LNG Liquified Natural Gas
  • the object of the invention is referred to steam turbine propulsion installations that are obliged to operate at low loads by recent IMO legislation and hybrid propulsion installations which use marine boilers and steam systems including vessels where hybrid propulsion is retrofitted for reducing emissions while the speed of vessels is maintained or reaches operationally optimal levels of speed, taking in account the risk of corrosion by sulphur dioxide at low exhaust gas temperatures, modifying the steam cycle in order to recover its efficiency and saving a substantial amount of steam and, consequently, fuel in an economical and efficient way when the vessel steam plant operates at low loads.
  • the more frequently used main steam boilers of the type normally used in the propulsion on steam turbine LNG carriers includes boilers which integrate the following main parts:
  • furnace screen water tubes located between furnace and superheater in one or more rows.
  • main generating bank located after the superheater tubes.
  • HSHFO low sulphur heavy fuel oil
  • MDO marine diesel oil
  • ULSMDO ultralow sulphur marine diesel oil
  • Vessels would be classified as A, B, C, D and E, A class Vessels being the most efficient, and E class Vessels being the less efficient. It is likely that IMO, under Carbon Intensity Index (CH) will oblige D and E class Vessels to improve its efficiency. Probably, most, if not all, of steam turbine LNG carriers will be ranked D or E.
  • CH Carbon Intensity Index
  • the conventional steam turbine marine power plants are designed in such a way that if power decreases, the power plant efficiency decreases at an increasing rate. For example, when reducing the shaft horsepower by 50%, power plant efficiency decreases about a 25%.
  • the present invention refers to a method for conversion of Liquefied Natural Gas carriers steam or hybrid propulsion installations to reduce the required emissions of exhaust gases by IMO while maintaining the efficiency of the vessels or, at least, reducing the efficiency to acceptable levels and decreasing fuel consumption of steam or hybrid propulsion installations.
  • the method which is the subject of the invention attempts to solve the problems described above, by conversion of LNG carriers steam or hybrid propulsion installations.
  • This method comprises a series of phases that could be applied in a new installation or in a conventional installation.
  • emissions are reduced to the required standards of the IMO while carriers maintain the speed of the vessels, limit the reduction of vessel's speed or reach optimal speed according to the TCH party requirements.
  • the method of the invention has two different targets:
  • This target implies to reach a given value of the EEXI as defined and required by IMO. To reach the required value one or several of the proposed efficiency improvements may be applied, until the attained value of the EEXI of a given Vessel meets IMO requirement. Same applies to CH, with the additional requirement of progressive improvement over the years.
  • Second target is making the Vessels more attractive commercially by reducing its energy consumption.
  • the first aspect of the invention comprises a method which incorporates a low- pressure economizer in marine boilers of the type used in the steam or hybrid propulsion installation driven existing in LNG carriers, so, propulsion installations can operate at low loads getting levels of efficiency closer those of the propulsion installation when it works at high loads.
  • An high-pressure economiser exists in the exhaust gas duct, which uses the heat from the exhaust gases to increase the temperature of the boiler feed water, thereby reducing the fuel used and increasing the efficiency of the installation.
  • the first aspect of the method is characterised by modifying the exhaust gas duct and placing a low-pressure economiser after the main economiser.
  • the water supply to this low pressure is made from the main condenser extraction water circuit where the water temperature is low, making the heat exchange in the low-pressure economizer more efficient.
  • the introduction of the low-pressure economiser into the installation is carried out as follows: installing the low-pressure economiser either in line or in by-pass with the existing ducting. In this case, there are two options:
  • the boiler feed water circulating through the low-pressure economiser increases its temperature by heat exchange with the exhaust gases, so that the exhaust gases are expelled from the boiler at a final temperature belowl 00 e C degree.
  • the design and arrangement of the low-pressure economizer will lower exhaust gas temperature recovering in this way heat. Depending on the design, it will be possible to condensate part of the water vapour content existing in the exhaust gas. In this case the amount of recovered heat will increase substantially.
  • the low-pressure economizer is to be designed in such a way that the condensed water is collected and sent outside exhaust gas stream. This additional heat recovery is possible because the low temperature of the Main condenser extraction water that is circulating inside the low-pressure economizer. Indeed, the materials and design of the low-pressure economizer shall be adequate to resist the potential corrosion at low temperature in case of some sulphur content in the exhaust gas.
  • the low-pressure economizer can be installed in both boilers or only in one boiler. Almost in all the steam turbine LNG carriers two main boilers are installed. However, the retrofit of the second economizer in only one of the two existing boilers could be a very good option, reducing costs and installation time, because as explained before, the second economizer installation is linked with the operation of the steam power plant at slow steaming. In this case, one possibility is to operate the steam plant with only one boiler.
  • the second aspect of the invention comprises a method which is based on the conversion of one or both existing boilers in a heat recovery steam generator (HRSG).
  • HRSG heat recovery steam generator
  • the second aspect of the method is characterised by modify one of the water tube walls of the existing boiler furnace creating an opening in the selected water tube wall by cutting a section of water tubes in order to allow the inlet into the furnace of the boiler of the exhaust gas of a Gas Turbine power generator or a Diesel Engine power generator in order to that the existing marine steam boiler will operate as Heat Recovery Steam Generator (HRSG) but keeping, when it is required, the capacity to operate as a dual fired boiler and been also able to operate simultaneously in both ways.
  • HRSG Heat Recovery Steam Generator
  • the water tubes that have been cut in order to create the exhaust gas opening for exhaust gas inlet will be substituted by new especially bended pipes in a different plan that are welded on both ends to the previous cuts in the water pipes, maintaining the continuity of the water circulation in all and any pipes of the water wall of the boiler furnace.
  • the shape of the bends of new water pipes section will be in three dimensions and designed to: guarantying the water circulation in all the pipes, maintaining the smoke tightness of the water pipe walls, and creating an overlapping of the new sections of water pipes with the remaining water pipes thus creating the opening for exhaust gas inlet and/or creating a duct for the power generator exhaust gas guiding such gas flow in the required direction.
  • one or both existing steam boilers may operate as fired boilers and/or as HRSG and or in both ways simultaneously.
  • Another option of modifying one of the existing boilers is introducing the gas turbine or diesel engine exhaust gas in the combustion air ducts after the forced draft fan and before combustion air entry in the furnace in such a way that the exhaust gas will enter in the boiler furnace through the top part existing openings in way of burners openings in the roof water pipes panel so that exhaust gas will flow inside the existing boiler in the same way that the combustion gases before conversion in a U shape flow.
  • Ducts are to be provided with all the customary fittings and arrangements.
  • the advantage of the second aspect of the invention is that existing boilers can be used as HRSG while keeping its ability to be used as MPMB or be used as fired and HRSG simultaneously.
  • the MPMB will perform adequately as HRSG provided that its heat exchange capacity is adequate to the amount and conditions of the Gas Turbine (GT) exhaust gas.
  • GT Gas Turbine
  • This heat exchange capacity is to be checked by adequate calculations. Indeed, the steam production will correspond to the amount and temperature of the exhaust gas.
  • the second aspect of the invention also method is supplemented by a third aspect of the operation consisting of retrofitting an additional steam superheater located in the newly retrofitted flue gas duct before the gas enters the furnace of the existing boiler through the created opening.
  • the new steam superheater will be connected to the existing superheated steam main pipe with adequate valves. Its inlet will be connected to the outlet of the existing superheater and its outlet will be connected to the boiler superheated steam main before the connection to the other boiler superheated steam main.
  • This connection then supplies superheated steam to the main turbines and the other main superheated steam users.
  • the temperature of the superheated steam will be higher than the temperature that can be achieved in the existing superheater of the existing main boiler, reaching a temperature similar or closer to temperature of the superheated steam in the existing dual gas and liquid fuel steam boiler.
  • the new steam superheater will be built with similar materials to those used in the existing superheater (high temperature steel alloys) and will consist mainly of superheating steam pipes and superheated steam collectors as well as required valves and controls.
  • the new superheater module could be isolated if necessary.
  • a small steam circulation using an adequate device, may be maintained to keep the adequate temperature in the new superheater tubes within acceptable limits when exposed to the residual level of radiation and convection without main steam circulation.
  • a fourth aspect of the invention which is based on integrating both existing and new auxiliary steam and water systems introducing in the selected piping points steam and/or heated water, as required, generated in a low-pressure exhaust boiler of conventional installation when works as exhaust gas steam generator (HRSG), which could be connected with the existing deaerator of the LNG Carrier-or said low pressure exhaust boiler can works independently.
  • the steam which circulates inside the low-pressure exhaust boiler is heated by the exhaust gas of new dual fuel power generator normally a Diesel Generator (DFDG), installed as part of the conversion to create a hybrid propulsion.
  • DFDG Diesel Generator
  • the relatively low energy steam and heated water produced in the HRSG are used to one or several of the following uses: heating main condenser extraction water before entering the deaerator, producing steam to be injected into mentioned deaerator, heating main boiler combustion air in the existing air heater and injecting steam in the crossover after high pressure turbine (HPT) and before low pressure turbine (LPT) as well as other miscellaneous auxiliary steam uses.
  • HPT high pressure turbine
  • LPT low pressure turbine
  • the integration system is relatively simple and cheap by using most of the existing piping systems and heat exchangers being now feed by the new steam and/or hot water available from HRSG and/or diesel generator retrofitting as part of the new hybrid propulsion.
  • the deaerator as steam/water separator in the new HRSG, the main such advantages are:
  • the deaerator is already connected with main condenser extraction pumps discharge.
  • Such discharge piping would be modified including the water circulation through the new HRSG economizer and discharge to the deaerator. In this way, the condenser extraction water is heated, to, or close to, the required temperature.
  • the HRSG forced water circulation pumps can easily aspire water from the lower part of the deaerator creating the circulation through the evaporator section of the HRSG and discharging to the deaerator, where the mixture of water and steam will separate.
  • the superheater section of the HRSG will be feed from the upper part of the deaerator (or an adequate existing steam pipe already directly connected to the steam part of the deaerator).
  • the superheated steam HRSG outlet will be connected to the different steam users where superheated steam is preferred, for example through a new connection to the crossover between HPT and LPT, where will be injected.
  • the deaerator is already connected with many steam systems. In this way the connection is made in a very simple way.
  • any water and steam drum require level and pressure meters and controls.
  • the deaerator is already fitted with such systems in a fully integrated way with existing installation.
  • the integration of the steam and hot water produced in the new HRSG can be performed using the deaerator or installing a new drum to separate steam and water as part of the retrofitted low pressure HRSG.
  • An additional application of the aspect is using the system as described as part of a combined cycle steam and Gas Turbine power system in the case of the two- pressure steam system.
  • the low-pressure system will use the deaerator as steam drum.
  • the low-pressure steam generated in the low-pressure evaporation section of the HRSG will be separated in the deaerator the superheated in the low-pressure superheater of the HRSG and then injected in the low-pressure turbine (LPT) through a connection in the existing crossover between HPT and LPT.
  • LPT low-pressure turbine
  • the invention could be complemented by a fifth aspect that includes implementing an automatic switching steam extractions system when the Vessel is operated at low loads in such a way that steam from main high-pressure turbine first extraction is switched automatically at certain loads range to the second extraction steam system.
  • This system is integrated installing several automatic valves and a branching pipe connecting first extraction steam piping system to second extraction steam piping system.
  • the existing and new fitted automatic valves will close and/or open sequentially in a programmed system driven by a parameter directly linked to the main turbines load.
  • valve interlocks will be included to avoid simultaneous entry of steam from two different automatic valves as well as pressure control valves if required.
  • this aspect could be applied to switching steam from the second extraction steam system feed from the cross over between HPT and LPT to the third extraction steam system feed from LPT.
  • the switch will be activated at a selected load where the pressure at a given steam extraction is too low to feed that extraction steam extraction system but is adequate to feed the next lower pressure steam extraction system.
  • the extraction system will be closed.
  • the switching system will normally be applied simultaneously with the first aspect of the invention with the low-pressure economizer to complement it or in fully independent way.
  • the system may be applied to switch one pair of extractions (first to second extraction) or two pairs of extractions (the previous and second to third extraction) as considered convenient.
  • the first aspect of the invention is directly applicable to steam propulsion installations and will improve efficiency at any load but specially at low loads in order to compensate the loss of efficiency due to low load operation.
  • the second aspect of the invention is directly applicable to hybrid propulsion installation, when a GT (Gas Turbine) or a DFDG (Dual Fuel Diesel Generator) is retrofitted and will improve steam cycle and overall efficiency. While keeping the Vessel compliant with IMO EEXI regulations, will contribute to increase the power and speed at which the vessel can operate.
  • GT Gas Turbine
  • DFDG Direct Fuel Diesel Generator
  • the second aspect can be complemented by the third aspect of the invention to achieve also optimal working requirements in terms of exhaust emissions.
  • the fourth aspect that is applicable to hybrid propulsion installations when a DFDG or GT is retrofitted, could be applied alternatively to the second and third aspects of the invention, using a low-pressure exhaust boiler of conventional installations which is connected with the LNG carrier existing steam system through the deaerator or a new steam/water drum
  • Figure 1. Shows a modification of an existing exhaust gas outlet of LNG carrier boiler.
  • Figure 2. Shows a modification of the tubes inside the combustion chamber of LNG carrier boiler.
  • Figure 3. Shows a section view of the tubes inside the combustion chamber of LNG carrier boiler.
  • Figure 4.- Shows an integration of a superheater before the LNG carrier boiler.
  • Figure 5. Shows an integration of an auxiliary steam and water system in the LNG carrier propulsion installation.
  • FIG. 6 Shows an integration of an automatic switching extraction system in the LNG carrier propulsion installation.
  • Figure 1 shows a modification of a LNG carrier steam or hybrid propulsion installation which comprises a main condenser (5), a LNG carrier boiler (1) and a deaerator (53) connected to the main condenser (5) and to a LNG carrier boiler (1 ).
  • the LNG carrier boiler (1 ) comprises a combustion chamber (10), an exhaust gas outlet duct (18) connected to the combustion chamber (10), a high- pressure economiser (7) located inside the exhaust gas outlet duct (18) and a first steam superheater (4) located inside the combustion chamber (10).
  • the modification is made by connecting (18) after the high-pressure economiser (7), which is located inside the existing gas outlet (18), a supplementary exhaust gas duct (23) and integrating a low-pressure economiser (22) inside the supplementary exhaust gas duct (23).
  • the low-pressure economiser (22) is configured to use the exhaust gases which circulate inside the exhaust gas outlets (18, 23) to heat the water going from the main condenser (5) to the deaerator (53), where said water is driven by an extraction pump (55) which is connected to the main condenser (5), when the steam or hybrid propulsion installation operates at low loads
  • the quantity of live steam which the deaerator (53) require to reach its design temperature will be reduced accordingly.
  • FIG 2 shows a modification of the tubes which are inside the LNG carrier boiler (1) creating an opening (50) in the combustion furnace (11) by cutting a section of several existing waterwall tubes (47) and substituting that section by a new curved pipes (48) section overlapping remaining said existing tubes (47) and creating said opening (50) in one wall of the combustion chamber (11) to allow the inlet of exhaust gases from a Gas Turbine Power Generator (GTPG) (30).
  • GTPG Gas Turbine Power Generator
  • the LNG carrier boiler (1 ) uses said exhaust gases to maintain the efficiency at low operative loads generating steam and increasing its operational temperature when the hybrid propulsion installation operates at low loads, like it worked at high operative loads.
  • Another advantage is the decrease of use of fuel because said exhaust gases do not escape to the atmosphere, and also the LNG carrier boiler (1) can work as HRSG (Heat Recovery Steam Generator) or as dual fired boiler.
  • Figure 3 shows a section view of the modification of the tubes which are inside the LNG carrier boiler (1) where an upper view of the disposition of the existing tubes (47) and the new curved pipes (48).
  • Figure 4 shows an integration of a second steam superheater (35) inside a GTPG (30) exhaust duct (8) which connects with LNG carrier boiler (1 ) and leads into the opening (50).
  • the second steam superheater (35) is integrated before the opening (50) created in the LNG carrier boiler (1 ) in order to increase the temperature exhaust gases that came from the GTPG (30) so that, the operational temperature of the LNG carrier boiler (1 ) when the hybrid propulsion installation operates at low loads.
  • Figure 5 shows an integration of a retrofitted system (9), formed by a first set of water pipes (26), a second set of steam/water pipes (27) and a third set of steam pipes (28), and a steam/water separator drum (67).
  • Figure 5 shows the components of a hybrid propulsion installations, where said components are a main condenser (5), an extraction pump (55) connected to the main condenser (5), a first step water heater (65) connected to the extraction pump (55), a deaerator (53) connected to the first step water heater (65), a LNG carrier boiler (1) connected to the deaerator (53), a High-Pressure Turbine (69) connected to the LNG carrier boiler (1), a Low-Pressure Turbine (80) connected to the High-Pressure Turbine (69) by a crossover pipe (77), a low-pressure exhaust boiler (59) which comprises a second low-pressure economiser (60), a saturated steam generator (61), and a low-pressure superheater (63), a DFDG (54) connected to the low-pressure exhaust boiler (59), and an auxiliary set of steam consumers (58).
  • a main condenser (5) an extraction pump (55) connected to the main condenser (5)
  • a first step water heater (65)
  • the method comprises the integration of the retrofitted system (9) are based on connecting the main condenser (5) extraction water going from first step water heater (65) to the second low-pressure economiser (60) and from the second low- pressure economiser (60) to the deaerator (53) directly or through the steam/water separator drum (67) by the first steam pipes (26) in order to heat the water coming from the main condenser (5) before entering inside the deaerator (53).
  • Next step includes connecting the saturated steam generator (61) to the deaerator (53) directly or through the steam/water separator drum by the second steam-water pipes (27) in order to heat the water of the deaerator (53) which feeds the LNG carrier boiler (1).
  • the deaerator (53) is connected to the low-pressure superheater (63) and the low-pressure superheater (63) to the crossover pipe (77) and the first steam consumers (58) by the third steam pipes (28) in order to supply the steam which leads out the low-pressure superheater (63) to the crossover pipe (77) and the first steam consumers (58), substituting in this way the live steam supplied from the LNG carrier boiler (1) by steam coming said heating steam from the deaerator (53) or steam/water separator drum (67).
  • the retrofitted system (9) is integrated in selected piping points of the installation with the new steam system and use the heated water and steam generated in the low-pressure exhaust boiler (59) heated by the exhaust gas of the DFDG (54), to heat the water of that came from a main condenser (5) before the water enters into the deaerator (53), to heat combustion air of the LNG carrier boiler(1) using the existing steam/air heater, injecting steam in a crossover (77) before Low Pressure Turbine (LPT) (80) of the installation and, in general, substituting the auxiliary steam coming from the LNG carrier boiler (1).
  • LPT Low Pressure Turbine
  • FIG. 6 shows the integration in the existing extraction steam system of an automatic switching extractions system (40) which comprises a first extraction steam pipe (32) connecting first extraction steam system coming from HPT (69) with a second extraction steam pipe (33) coming from the crossover (77) and a third extraction steam pipe (34) connecting second extraction steam system coming from the crossover (77) with third extraction steam system coming from LPT (80).
  • the system also comprises several automatic valves (70, 71 , 72, 76, 78, 79, 81 ). Valves (70, 72) are opened after existing first and second extraction automatic valves (71 , 78) are closed. In this way, a set of second extraction steam consumers (74) are supplied with steam coming from first extraction.
  • the automatic switching extractions system (40) is configured to control a steam extraction system of the steam or hybrid propulsion installation at low load operations when the pressure at a given steam extraction is too low to feed the corresponding system but is still able to feed next lower pressure system.
  • the automatic switching extractions system (40) is connected to an automatic extraction controller (41 ) that controls the automatic switching extractions system (40).

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Ocean & Marine Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Fluid Mechanics (AREA)
  • Water Supply & Treatment (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)

Abstract

Procédé de conversion d'installations du type utilisé dans le cadre la propulsion hybride de navires méthaniers, ledit procédé étant basé sur la modification d'une chaudière de navire méthanier de l'installation, la modification de la sortie d'échappement existante intégrant une nouvelle sortie de gaz d'échappement, la création d'une ouverture dans une chambre de combustion de ladite chaudière de navire méthanier, l'introduction de gaz d'échappement à partir d'un GTPG à l'intérieur de l'ouverture créée et l'ajout d'un second surchauffeur à l'intérieur de la sortie de gaz d'échappement entre le GTPG et la chaudière de navire méthanier, l'intégration d'un système auxiliaire de vapeur et d'eau et l'intégration d'un système d'extraction à commutation automatique, le raccordement des deux systèmes à l'installation de propulsion hybride.
PCT/EP2021/078912 2021-10-19 2021-10-19 Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier WO2023066462A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP21798323.8A EP4200521A1 (fr) 2021-10-19 2021-10-19 Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier
PCT/EP2021/078912 WO2023066462A1 (fr) 2021-10-19 2021-10-19 Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier

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PCT/EP2021/078912 WO2023066462A1 (fr) 2021-10-19 2021-10-19 Procédé de conversion d'installations de propulsion à vapeur ou hybride de navire méthanier

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Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR82360E (fr) * 1961-09-20 1964-01-31 Siemens Ag Centrale thermique mixte du type gaz-vapeur
FR2043956A5 (fr) * 1969-05-14 1971-02-19 Stein Industrie
JPS55109708A (en) * 1979-02-19 1980-08-23 Hitachi Ltd Composite power plant
JPS5898606A (ja) * 1981-12-08 1983-06-11 Mitsubishi Heavy Ind Ltd 複合ガスタ−ビン発電プラント
GB2143589A (en) * 1983-07-18 1985-02-13 Dba Parga Propulsion plant for steam turbine driven ship
JPH06137113A (ja) * 1992-10-27 1994-05-17 Toshiba Corp コンバインドサイクルプラントの給水処理装置
US5642614A (en) * 1993-12-30 1997-07-01 Combustion Engineering, Inc. Gas turbine combined cycle system
US6343570B1 (en) * 1997-08-25 2002-02-05 Siemens Aktiengesellschaft Steam generator, in particular waste-heat steam generator, and method for operating the steam generator
JP2011089484A (ja) * 2009-10-23 2011-05-06 Kawasaki Heavy Ind Ltd 船舶用蒸気タービン設備
WO2013035638A1 (fr) * 2011-09-05 2013-03-14 三菱重工業株式会社 Installation de turbine à vapeur
WO2013061928A1 (fr) * 2011-10-24 2013-05-02 三菱重工業株式会社 Système de traitement de gaz liquéfié, procédé de commande pour ce système, transporteur de gaz liquéfié équipé de ce système et installation de stockage de gaz liquéfié équipée de ce système
KR20150049903A (ko) * 2013-10-31 2015-05-08 대우조선해양 주식회사 저압 공급수 히터의 열교환 시스템
US20150226090A1 (en) * 2012-09-27 2015-08-13 Siemens Aktiengesellschaft Gas and steam turbine system having feed-water partial-flow degasser
DE102016214960B3 (de) * 2016-07-11 2017-07-06 Siemens Aktiengesellschaft Kraftwerksanlage mit optimierter Vorwärmung von Speisewasser für tiefaufgestellte Turbosätze
EP3244030A1 (fr) * 2016-05-09 2017-11-15 General Electric Technology GmbH Centrale thermique à vapeur avec amplification de puissance grâce à l'utilisation d'un réchauffage de drain de chauffage supérieur
JP6526763B2 (ja) * 2017-09-28 2019-06-05 三菱重工業株式会社 ボイラプラント及びボイラプラント運転方法

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR82360E (fr) * 1961-09-20 1964-01-31 Siemens Ag Centrale thermique mixte du type gaz-vapeur
FR2043956A5 (fr) * 1969-05-14 1971-02-19 Stein Industrie
JPS55109708A (en) * 1979-02-19 1980-08-23 Hitachi Ltd Composite power plant
JPS5898606A (ja) * 1981-12-08 1983-06-11 Mitsubishi Heavy Ind Ltd 複合ガスタ−ビン発電プラント
GB2143589A (en) * 1983-07-18 1985-02-13 Dba Parga Propulsion plant for steam turbine driven ship
JPH06137113A (ja) * 1992-10-27 1994-05-17 Toshiba Corp コンバインドサイクルプラントの給水処理装置
US5642614A (en) * 1993-12-30 1997-07-01 Combustion Engineering, Inc. Gas turbine combined cycle system
US6343570B1 (en) * 1997-08-25 2002-02-05 Siemens Aktiengesellschaft Steam generator, in particular waste-heat steam generator, and method for operating the steam generator
JP2011089484A (ja) * 2009-10-23 2011-05-06 Kawasaki Heavy Ind Ltd 船舶用蒸気タービン設備
WO2013035638A1 (fr) * 2011-09-05 2013-03-14 三菱重工業株式会社 Installation de turbine à vapeur
WO2013061928A1 (fr) * 2011-10-24 2013-05-02 三菱重工業株式会社 Système de traitement de gaz liquéfié, procédé de commande pour ce système, transporteur de gaz liquéfié équipé de ce système et installation de stockage de gaz liquéfié équipée de ce système
US20150226090A1 (en) * 2012-09-27 2015-08-13 Siemens Aktiengesellschaft Gas and steam turbine system having feed-water partial-flow degasser
KR20150049903A (ko) * 2013-10-31 2015-05-08 대우조선해양 주식회사 저압 공급수 히터의 열교환 시스템
EP3244030A1 (fr) * 2016-05-09 2017-11-15 General Electric Technology GmbH Centrale thermique à vapeur avec amplification de puissance grâce à l'utilisation d'un réchauffage de drain de chauffage supérieur
DE102016214960B3 (de) * 2016-07-11 2017-07-06 Siemens Aktiengesellschaft Kraftwerksanlage mit optimierter Vorwärmung von Speisewasser für tiefaufgestellte Turbosätze
JP6526763B2 (ja) * 2017-09-28 2019-06-05 三菱重工業株式会社 ボイラプラント及びボイラプラント運転方法

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