# US 2014/0150994 A1 · Air-cooled heat exchanger and system and method of using the same to remove waste thermal energy from radioactive materials > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150994 A1 - Document ID: US20140150994A1 - Status: Published application - Kind: A1 - Application number: 14/113,990 - Filed: 2012-04-25 - Published: 2014-06-05 - Earliest claimed: 2011-04-25 - Assignees: Holtec International - Inventors: Krishna P. Singh; Joseph Rajkumar - Web page: https://patentgrep.com/patent/US20140150994A1 ## CPC - G21C 15/22: Structural association of coolant tubes with headers (joints of tubes in general F16L) - G21C 15/18: Emergency cooling arrangements; Removing shut-down heat - G21D 3/04: Safety arrangements (emergency protection of reactor G21C9/00) - Y02E 30/00: Energy generation of nuclear origin - Y02E 30/30: Nuclear fission reactors - G21C: NUCLEAR REACTORS (fusion reactors, hybrid fission-fusion reactors G21B; nuclear explosives G21J) - G21D: NUCLEAR POWER PLANT - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A system for removing thermal energy generated by radioactive materials is provided. The system comprises an air-cooled shell-and- tube heat exchanger, comprising a shell and plurality of heat exchange tubes arranged in a substantially vertical orientation within the shell, the heat exchange tubes comprising interior cavities that collectively form a tube-side fluid path, the shell forming a shell-side fluid path that extends from an air inlet of the shell to an air outlet of the shell, the air inlet at a lower elevation than the air outlet; a heat rejection closed-loop fluid circuit comprising the tube-side fluid path, a coolant fluid flowing through the heat rejection closed-loop fluid circuit, the heat rejection closed-loop fluid circuit thermally coupled to the radioactive materials; and the air-cooled shell-and-tube heat exchanger transferring thermal energy from the coolant fluid flowing through the tube-side fluid path to air flowing through the shell-side fluid path. ## Claims ### Claim 1 A system fur removing thermal energy generated by radioactive materials comprising: an air-cooled heat exchanger; a heat rejection closed-loop fluid circuit comprising a tube-side fluid path of the air-cooled heat exchanger, a coolant fluid flowing through the heat rejection closed-loop fluid circuit, the heat rejection closed-loop fluid circuit thermally coupled to the radioactive materials so that thermal energy generated by the radioactive materials is transferred to the coolant fluid; and the air-cooled heat exchanger comprising a shell-side fluid path having a first air inlet, a second air inlet and an air outlet, the first air inlet located at a first elevation, the second air inlet located at a second elevation, and the air outlet located at a third elevation, the second elevation greater than the first elevation and the third elevation greater than the second elevation, the air-cooled heat exchanger transferring thermal energy from the coolant fluid flowing through the tube-side fluid path to an flowing through the shell-side fluid path. ### Claim 2 (depends on 1) The system of claim 1 wherein the shell-side fluid path comprises a venturi located at an elevation between the second air inlet and the air outlet. ### Claim 3 (depends on 2) The system of claim 2 wherein the tube-side fluid path comprises internal cavities of a plurality of heat exchange tubes, the plurality of heat exchange tubes located within the shell-side fluid path, wherein the venturi is created by fins of the plurality of heat exchange tubes. ### Claim 4 (depends on 3) The system of claim 3 wherein the plurality of heat exchange tubes form a tube bundle having a longitudinal axis, and wherein each of the fins of the plurality of heat exchange tubes comprise opposing surfaces that extend substantially parallel to the longitudinal axis. ### Claim 5 (depends on 1) The system of claim 1 wherein the shell-side fluid path comprises a first free transverse cross-sectional area at the second elevation and a second free transverse cross-sectional area at an elevation between the second air inlet and the air outlet, the second free transverse cross-sectional area being less than the first free transverse cross-sectional area. ### Claim 6 (depends on 5) The system of claim 5 wherein the shell-side fluid path comprises a third free transverse cross-sectional area at the third elevation, the third free transverse cross-sectional area being greater than the second free transverse cross-sectional area. ### Claim 7 (depends on 1) The system of claim 1 further comprising: an intermediate heat exchanger; an intermediate closed-loop fluid circuit comprising, in operable fluid coupling, a pool of a liquid and a first fluid path of the intermediate heat exchanger, the radioactive materials immersed in the pool of the liquid, the liquid flowing through the intermediate closed-loop fluid circuit; and the heat rejection closed-loop fluid circuit further comprising a second fluid path of the intermediate heat exchanger, the intermediate heat exchanger transferring thermal energy from the liquid flowing through the first fluid path to the coolant fluid flowing through the second fluid path. ### Claim 8 (depends on 7) The system of claim 7 wherein the pool of the liquid and the intermediate heat exchanger are contained within a containment structure. ### Claim 9 (depends on 1) The system of claim 1 wherein the tube-side fluid path of the air-cooled heat exchanger comprises internal cavities of a plurality of heat exchange tubes, the plurality of heat exchange tubes arranged in a substantially vertical orientation. ### Claim 10 (depends on 8) The system of claim 8 wherein the plurality of heat exchange tubes collectively form a tube bundle that extends along a longitudinal axis, and the tube bundle comprising finned tube sections and a non-finned tube section arranged in axial alignment, the second air inlet transversely aligned with the non-finned tube section. ### Claim 11 (depends on 10) The system of claim 10 wherein the finned tube sections and the non-finned tube section alternate along the longitudinal axis. ### Claim 12 (depends on 10) The system of claim 10 further comprising a plurality of the non-firmed tube sections, each of the first air inlet, the second air inlet and the air outlet transversely aligned with one of the non-finned tube sections. ### Claim 13 (depends on 10) The system of claim 10 further comprising: the air-cooled beat exchanger comprising a top tube sheet and a bottom tube sheet, the plurality of heat exchange tubes extending from the top tube sheet to the bottom tube sheet, the first air inlet located adjacent the bottom tube sheet and the air outlet located adjacent the top tube sheet; and the tube-side fluid path of the air-cooled heat exchanger comprising a coolant fluid inlet header and a coolant fluid outlet header, the internal cavities of the plurality of heat exchange tubes forming passageway between the coolant fluid inlet header and the coolant fluid outlet header. ### Claim 14 (depends on 1) The system of claim 1 wherein the air-cooled heat exchanger comprises a s each of the first air inlet, the second air inlet and the air outlet formed in the shell. ### Claim 15 (depends on 14) The system of claim 14 further comprising: a shroud forming a shroud cavity, the air-cooled heat exchanger located within the shroud cavity, the shroud cavity comprising a shroud outlet plenum circumferentially surrounding the air-cooled heat exchanger, the air outlet of the shell located within the shroud outlet plenum; and a chimney forming a passageway from the shroud outlet plenum to an ambient environment. ### Claim 16 (depends on 1) The system of claim 1 further comprising a blower for inducing air flow through the shell-side fluid path. ### Claim 17 A system for removing thermal energy generated by radioactive materials comprising: an air-cooled shell-and-tube heat exchanger comprising a shell and plurality of heat exchange tubes arranged in a substantially vertical orientation within the shell, the plurality of heat exchange tubes comprising interior cavities that collectively form a tube-side fluid path, the shell forming a shell-side fluid path that extends from an air inlet of the shell to an air outlet of the shell, the first air inlet located at a lower elevation than the air outlet; a heat rejection closed-loop fluid circuit comprising the tube-side fluid path of the air-cooled heat exchanger, a coolant fluid flowing through the heat rejection closed-loop fluid circuit, the heat rejection closed-loop fluid circuit thermally coupled to the radioactive materials so that thermal energy generated by the radioactive materials is transferred to the coolant fluid; and the air-cooled shell-and-tube heat exchanger transferring thermal energy from the coolant fluid flowing through the tube-side fluid path to air flowing through the shell-side fluid path. ### Claim 18 (depends on 17) The system of claim 17 further comprising a pool of a liquid, the radioactive materials immersed in the pool of the liquid, wherein thermal energy generated by the radioactive materials is transferred to the liquid of the pool prior to being transferred to the coolant fluid. ### Claim 19 (depends on 17) The system of claim 17 further comprising: a shroud forming a shroud cavity, the shell-and-tube air-cooled heat exchanger located within the shroud cavity, the shroud cavity comprising a shroud outlet plenum circumferentially surrounding the shell-and-tube air-cooled heat exchanger, the air outlet of the shell located within the shroud outlet plenum; and a chimney forming a passageway from the shroud outlet plenum to an ambient environment. ### Claim 20 (depends on 17) The system of claim 17 further comprising a blower for inducing air flow through the shell-side fluid path. ### Claim 21 (canceled) ### Claim 22 (depends on 17) The system of claim 17 wherein the shell-side fluid path comprises a venturi located at an elevation between the air inlet and the air outlet, the venturi created by fins of the plurality of heat exchange tubes. ### Claim 23 (canceled) ### Claim 24 (depends on 22) The system of claim 22 wherein the shell comprises a second air inlet located at an elevation between the air inlet and the air outlet, the venturi located between the second air inlet and the air outlet. ### Claim 25 (canceled) ### Claim 26 (depends on 17) The system of claim 17 wherein the plurality of heat exchange tubes collectively form a tube bundle that extends along a longitudinal axis, and the tube bundle comprising finned tube sections and non-finned tube sections arranged in alternating axial alignment. ### Claim 27 A tube-and-shell air-cooled heat exchanger apparatus comprising: a shell having a shell cavity, a primary air inlet at a first elevation, a secondary air inlet at a second elevation, and an air outlet at a third elevation, wherein the second elevation is greater than the first elevation and the third elevation is greater than the second elevation, each of the primary an inlet, the secondary an inlet, and the air outlet forming a passageway through the shell to a shell-side fluid path; and a plurality of heat exchange tubes that collectively form a tube bundle having a substantially vertical longitudinal axis, the tube bundle located within the shell cavity, a tube-side fluid path comprising interior cavities of the plurality of heat exchange tubes. ### Claim 28 (depends on 27) The tube-and-shell air-cooled heat exchanger apparatus of claim 27 wherein the tube bundle comprises finned tube sections and a non-finned tube section arranged in axial alignment, the secondary air inlet transversely aligned with the non-finned tube section. ### Claim 29 (canceled) ### Claim 30 (depends on 28) The tube-and-shell air-cooled heat exchanger apparatus of claim 28 further comprising a plurality of the non-finned tube sections, each of the primary air inlet, the secondary air inlet and the air outlet transversely aligned with one of the non-finned tube sections. ### Claim 31 (canceled) ### Claim 32 (depends on 27) The tube-and-shell air-cooled heat exchanger apparatus of claim 27 wherein the shell-side fluid path comprises a venturi located at an elevation between the secondary air inlet and the air outlet, the venturi created by fins of the plurality of heat exchange tubes. ### Claim 33 (canceled) ### Claim 34 (canceled) ### Claim 35 (depends on 27) The tube-and-shell air-cooled heat exchanger apparatus of claim 27 wherein the shell-side fluid path comprises a first free transverse cross-sectional area at the second elevation and a second free transverse cross-sectional area at an elevation between the secondary air inlet and the an outlet, the second free transverse cross-sectional area being less than the first free transverse cross-sectional area. ### Claim 36 (depends on 27) The tube-and-shell air-cooled heat exchanger apparatus of claim 27 further comprising: a top tube sheet and a bottom tube sheet, the plurality of heat exchange tubes extending from the top tube sheet to the bottom tube sheet, the first air inlet located adjacent the bottom tube sheet and the air outlet located adjacent the top tube sheet; and the tube-side fluid comprising a coolant fluid inlet header and a coolant fluid outlet header, the internal cavities of the plurality of heat exchange tubes forming passageway between the coolant fluid inlet header and the coolant fluid outlet header. ### Claim 37 (depends on 27) The tube-and-shell air-cooled heat exchanger apparatus of claim 27 further comprising: a shroud forming a shroud cavity, the shell located within the shroud cavity, the shroud cavity comprising a shroud outlet plenum circumferentially surrounding the shell, the air outlet located within the shroud outlet plenum; and a chimney forming a passageway from the shroud outlet plenum to an ambient environment. ### Claim 38 (canceled)