# US 11,028,734 B2 · Rankine cycle plant and process for the regasification of liquefied gas > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,734 B2 - Document ID: US11028734B2 - Status: Granted - Kind: B2 - Application number: 16/625,886 - Filed: 2018-06-22 - Published: 2020-05-14 - Granted: 2021-06-08 - Earliest claimed: 2017-06-23 - Assignees: Exergy International S.R.L. - Applicants: Exergy S.P.A. - Inventors: Claudio Spadacini - Web page: https://patentgrep.com/patent/US11028734B2 ## CPC - F01K 11/02: the engines being turbines - F01K 25/10: the vapours being cold, e.g. ammonia, carbon dioxide, ether - F01K: STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES (gas-turbine or jet-propulsion plants F02; nuclear power plants, engine arrangements therein G21D) ## Abstract A Rankine cycle plant for the regasification of liquefied gas, includes: a Rankine closed loop system; a source of liquefied gas at a cryogenic temperature operatively coupled to a condenser to receive heat from a working fluid from an expansion turbine to take the liquefied gas to the gaseous state; a source of a heating fluid at a temperature higher than the cryogenic temperature operatively coupled to an evaporator to transfer heat to the working fluid coming from the condenser. The expansion turbine is radial centrifugal with at least one auxiliary outlet interposed between successive stages. The condenser is multilevel and has at least two condensing chambers, wherein a lower chamber being connected to an outflow opening of the expansion turbine and an upper chamber connected to the auxiliary outlet of the expansion turbine. ## Claims ### Claim 1 A Rankine cycle plant for the regasification of liquefied gas, comprising: a Rankine closed loop system comprising at least: one evaporator; an expansion turbine provided with an inflow opening, an outflow opening and at least one auxiliary outlet; a generator operatively connected to the expansion turbine; a condenser; a pump; conduits configured to connect the evaporator, the expansion turbine, the condenser and the pump according to a closed cycle in which a working fluid circulates; a source of liquefied gas at a cryogenic temperature, wherein the source of liquefied gas is operatively coupled to the condenser to receive heat from the working fluid flowing out from the expansion turbine so as to take the liquefied gas to the gaseous state; a source of a heating fluid at a higher temperature than the cryogenic temperature, wherein the source of heating fluid is operatively coupled to the evaporator to transfer heat to the working fluid coming from the condenser; wherein the expansion turbine is a radial centrifugal turbine, wherein said at least one auxiliary outlet is interposed between successive stages of said expansion turbine, and wherein the condenser is a multilevel condenser and comprises at least two condensing chambers, a lower chamber of said at least two condensing chambers is connected to the outflow opening and an upper chamber of said at least two condensing chambers is connected to said at least one auxiliary outlet, and wherein the expansion turbine comprises a single rotor disc and a plurality of stages radially arranged one after the other at a front face of the rotor disc, and wherein the auxiliary outlet opens between two of said stages. ### Claim 2 (depends on 1) The plant according to claim 1, wherein the expansion turbine comprises a plurality of auxiliary outlets each interposed between successive stages. ### Claim 3 (depends on 1) The plant according to claim 1, wherein the multilevel condenser comprises a casing delimiting therein said at least two condensing chambers and an outflow duct connecting the upper chamber to the lower chamber. ### Claim 4 (depends on 3) The plant according to claim 3, wherein the multilevel condenser comprises a plurality of condensing chambers arranged one over the other and a plurality of ducts connecting said condensing chambers to each other in a cascade fashion. ### Claim 5 (depends on 1) The plant according to claim 1, wherein the condenser has a series of inner septa that partition it internally in said condensing chambers. ### Claim 6 (depends on 3) The plant according to claim 3, wherein the casing of the condenser has an elongated shape and mainly a vertical extension. ### Claim 7 (depends on 4) The plant according to claim 4, wherein rising upwards with respect to the condenser, successive chambers are connected to auxiliary outlets of the expansion turbine at increasing pressure. ### Claim 8 (depends on 1) The plant according to claim 1, wherein the condenser comprises at least one tube or tube bundle connected to the source of liquefied gas; wherein said at least one tube or tube bundle passes through said at least two condensing chambers; wherein the liquefied gas flows from the bottom upwards through said at least one tube or tube bundle. ### Claim 9 (depends on 1) The plant according to claim 1, wherein the pump is only one and it is operatively arranged between the lower chamber of the condenser and the evaporator for pumping the condensed working fluid up to said evaporator. ### Claim 10 (depends on 1) The plant according to claim 1, wherein the conduits comprise a conduit connecting the lower chamber of the condenser and the evaporator, wherein a section of said conduit passes through at least one chamber of the condenser. ### Claim 11 (depends on 1) The plant according to claim 1, comprising a first and a second expansion turbine, wherein an outflow opening of the first expansion turbine is connected to an inflow opening of the second expansion turbine, wherein the first and/or the second expansion turbine has at least one auxiliary outlet. ### Claim 12 (depends on 11) The plant according to claim 11, comprising a heat exchanger located between the outflow opening of the first expansion turbine and the inflow opening of the second expansion turbine and operatively coupled to the source of heating fluid. ### Claim 13 (depends on 1) The plant according to claim 1, wherein the working fluid is selected from the group comprising: organic fluids, hydrocarbons, CO2, N2O. ### Claim 14 (depends on 1) The plant according to claim 1, wherein the heating fluid entering into the evaporator has a temperature (Thf) comprised between 5° C. and 70° C. ### Claim 15 (depends on 1) The plant according to claim 1, wherein the heating fluid is seawater. ### Claim 16 (depends on 1) The plant according to claim 1, wherein the liquefied gas flowing into the condenser has a temperature (Tlg) comprised between −155° C. and −173° C. ### Claim 17 A Rankine cycle plant for the regasification of liquefied gas, comprising: a Rankine closed loop system comprising at least: one evaporator; a single expansion turbine provided with an inflow opening, an outflow opening and at least one auxiliary outlet; a generator operatively connected to the expansion turbine; a condenser; a pump; conduits configured to connect the evaporator, the expansion turbine, the condenser and the pump according to a closed cycle in which a working fluid circulates; a source of liquefied gas at a cryogenic temperature, wherein the source of liquefied gas is operatively coupled to the condenser to receive heat from the working fluid flowing out from the expansion turbine so as to take the liquefied gas to the gaseous state; a source of a heating fluid at a higher temperature than the cryogenic temperature, wherein the source of heating fluid is operatively coupled to the evaporator to transfer heat to the working fluid coming from the condenser; wherein the expansion turbine is a radial centrifugal turbine, wherein said at least one auxiliary outlet is interposed between successive stages of said expansion turbine, and wherein the condenser is a multilevel condenser and comprises at least two condensing chambers, wherein a lower chamber of said at least two condensing chambers is connected to the outflow opening and an upper chamber of said at least two condensing chambers is connected to said at least one auxiliary outlet. ### Claim 18 (depends on 17) The plant according to claim 17, wherein the expansion turbine comprises a single rotor disc and a plurality of stages radially arranged one after the other at a front face of the rotor disc, and wherein the auxiliary outlet opens between two of said stages. ### Claim 19 (depends on 18) The plant according to claim 18, wherein the two stages between which the auxiliary outlet opens, are radially spaced to define a chamber for extracting the working fluid. ### Claim 20 (depends on 18) The plant according to claim 18, wherein the expansion turbine comprises a fixed housing, wherein the rotor disc is rotatably inserted into the fixed housing, wherein the auxiliary outlet is obtained in a front wall of the fixed housing.