DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Priority
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application No. KR10-2022-0186891, filed on 12/28/2022.
Response to Amendment
The amendments filed 04/09/2026 has been entered. Claims 1-4, 8-11, and 15 are currently amended and remain pending in the application. Claims 5-7, and 12-14 are cancelled.
Applicant’s amendment on the Drawings, Specification, and Claim objections have overcome have overcome each and every objection previously set forth in the Non-Final Office Action mailed 01/12/2026.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or non-obviousness.
Claims 1-4, 8-11, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Kuwahata et al. EP 3051111 A1, August 03, 2016 (hereinafter “Kuwahata”) in view of Hwang KR 20140023113 A, February 26, 2014 (hereinafter “Hwang”) in further view of Lee et al. KR 101947098 B1, February 17, 2016 (hereinafter “Lee”).
Regarding claim 1, Kuwahata discloses a waste-heat system onboard a ship utilizing recovered engine waste heat (paragraph 0009), comprising: a recovering heat from engine jacket cooling water and suppling the recovered heat recovery heat exchanger for steam generation (paragraphs 0036, 0056). However, Kuwahata fails to disclose a heat pump refrigerant circuit including an internal heat exchanger configured to recover heat from refrigerant discharged from the evaporator, a refrigerant compressor configured to compress refrigerant after internal heat exchange, a condenser configured to transfer heat from compressed refrigerant to water for steam generation, or a steam recompression unit.
Hwang discloses a complete heat pump refrigerant cycle (fig. 3) including: compressor (151), which compresses refrigerant (fig. 3; paragraph 0040); condenser (152), which transfers heat from compressed refrigerant to water ; evaporator (154), which evaporates refrigerant using recovered waste heat (paragraph 0039-0041); internal heat exchange (153), disposed between the condenser outlet and compressor inlet, configured to exchange heat between refrigerant leaving the condenser and refrigerant returning from the evaporator, thereby recovered heat from the refrigerant discharged from the evaporator before compression (fig. 3; paragraphs 0039-0041).
Lee discloses a steam production heat pump system including: a compressor (111) for compressing refrigerant (paragraphs 0021-0023); a condenser (112) configured to transfer heat from compressed refrigerant to circulating water for steam production (paragraphs 0023, 0031, 0047-0048); an internal heat exchanger / recuperator (115) disposed between the condenser outlet and compressor inlet for recovering heat from refrigerant returning from the evaporator while sub cooling refrigerant leaving the condenser (paragraphs 0006-0011, 0026); a steam generation cycle including flash tank (121) producing steam from heated water (paragraphs 0030-0032); a steam recompression or mechanical vapor recompression for increasing steam pressure and improving thermal efficiency (paragraph 0082).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify Kuwahata’s shipboard engine waste-heat recovery system by incorporating the heat-pump refrigerant cycle of Hwang, including evaporator (154), internal heat exchanger (153), compressor (151), and condenser (152), and further incorporating Lee’s steam recompression system. One would have been motivated to do so because each reference seeks to maximize recovery of otherwise wasted thermal energy and improve steam generation efficiency. Incorporating Hwang’s heat-pump cycle predictably increase thermal recovery from engine waste, while incorporating Lee’s mechanical vapor recompression predictably increases steam pressure, steam temperature, and overall system efficiency.
Regarding claim 2, Kuwahata discloses the engine cooling water (jacket water) at intermediate temperature used as a heat source (paragraph 0056). Engine jacket cooling water is a well-known mid-temperature heat source in marine systems, operating at a temperature between exhaust gas and seawater cooling, and is therefore properly considered “mid-temperature water”. It would have been obvious to one of ordinary skill in the art at the time of the invention to employ the recovered engine jacket cooling water of Kuwahata as the mid-temperature water source for heat pump refrigerant cycle taught by Hwang and incorporated into the steam generation system further taught by Lee, because its use in heat pump improves steam generation efficiency.
Regarding claim 3, Kuwahata discloses the engine cooling water at intermediate temperature used as a heat source (paragraph 0056), but fails to teach that it is discharged from the evaporator. However, Hwang teaches the refrigerant evaporation is discharged via heat pump (figure 3 – evaporator 154, paragraph 0041). Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to evaporate the refrigerant using the heat of mid-temperature engine coolant, as taught by Kuwahata in view of Hwang and Lee, because applying recovered engine coolant heat to a heat-pump refrigerant evaporation process is a predictable use of known thermal recovery techniques.
Regarding claim 4, Kuwahata fails to teach wherein the evaporator evaporates the refrigerant into gas having a humidity of 100%. However, Hwang discloses a heat pump refrigerant cycle including an evaporator (154), in which the refrigerant absorbs heat from the recovered heat source and is evaporated before being discharged from the evaporator for compression by compressor (153) (fig. 3; paragraphs 0039-0041). It would have been obvious to one of ordinary skill in the art at the time of the invention to modify the shipboard waste heat recovery system of Kuwahata with the heat pump refrigerant cycle taught by Hwang in view of claim 1. Because for the evaporator to evaporate the refrigerant into gas having a humidity of 100%, as taught by Hwang, because evaporation inherently produces saturated vapor under equilibrium conditions, making the claimed humidity an expected and predictable result. MPEP 2112.
Regarding claim 8, Kuwahata discloses a waste-heat system method onboard a ship utilizing recovered engine waste heat (paragraph 0009), comprising: a recovering heat from engine jacket cooling water and suppling the recovered heat recovery heat exchanger for steam generation (paragraphs 0036, 0056). However, Kuwahata fails to disclose a heat pump refrigerant circuit including an internal heat exchanger configured to recover heat from refrigerant discharged from the evaporator, a refrigerant compressor configured to compress refrigerant after internal heat exchange, a condenser configured to transfer heat from compressed refrigerant to water for steam generation, or a steam recompression unit.
Hwang discloses a complete heat pump refrigerant cycle (fig. 3) including: compressor (151), which compresses refrigerant (fig. 3; paragraph 0040); condenser (152), which transfers heat from compressed refrigerant to water ; evaporator (154), which evaporates refrigerant using recovered waste heat (paragraph 0039-0041); internal heat exchange (153), disposed between the condenser outlet and compressor inlet, configured to exchange heat between refrigerant leaving the condenser and refrigerant returning from the evaporator, thereby recovered heat from the refrigerant discharged from the evaporator before compression (fig. 3; paragraphs 0039-0041).
Lee discloses a steam production heat pump system including: a compressor (111) for compressing refrigerant (paragraphs 0021-0023); a condenser (112) configured to transfer heat from compressed refrigerant to circulating water for steam production (paragraphs 0023, 0031, 0047-0048); an internal heat exchanger / recuperator (115) disposed between the condenser outlet and compressor inlet for recovering heat from refrigerant returning from the evaporator while sub cooling refrigerant leaving the condenser (paragraphs 0006-0011, 0026); a steam generation cycle including flash tank (121) producing steam from heated water (paragraphs 0030-0032); a steam recompression or mechanical vapor recompression for increasing steam pressure and improving thermal efficiency (paragraph 0082).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify Kwahata’s shipboard engine waste-heat recovery system by incorporating the heat-pump refrigerant cycle of Hwang, including evaporator (154), internal heat exchanger (153), compressor (151), and condenser (152), and further incorporating Lee’s steam recompression system. One would have been motivated to do so because each reference seeks to maximize recovery of otherwise wasted thermal energy and improve steam generation efficiency. Incorporating Hwang’s heat-pump cycle predictably increase thermal recovery from engine waste, while incorporating Lee’s mechanical vapor recompression predictably increases steam pressure, steam temperature, and overall system efficiency.
Regarding claim 9, Kuwahata teaches the engine cooling water (jacket water) at intermediate temperature used as a heat source (paragraph 0056). Engine jacket cooling water is a well-known mid-temperature heat source in marine systems, operating at a temperature between exhaust gas and seawater cooling, and is therefore properly considered “mid-temperature water.” It would have been obvious to one of ordinary skill in the art at the time of the invention to employ the recovered engine jacket cooling water of Kuwahata as the mid-temperature water source for heat pump refrigerant cycle taught by Hwang and incorporated into the steam generation system further taught by Lee, because its use in heat pump improves steam generation efficiency.
Regarding claim 10, Kuwahata discloses the engine cooling water at intermediate temperature used as a heat source (paragraph 0056), but fails to teach that it is discharged from the evaporator. However, Hwang teaches the refrigerant evaporation is discharged via heat pump (figure 3 – evaporator 154, paragraph 0041). Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to evaporate the refrigerant using the heat of mid-temperature engine coolant, as taught by Kuwahata in view of Hwang and Lee, because applying recovered engine coolant heat to a heat-pump refrigerant evaporation process is a predictable use of known thermal recovery techniques.
Regarding claim 11, Kuwahata fails to teach wherein the evaporator evaporates the refrigerant into gas having a humidity of 100%. However, Hwang discloses a heat pump refrigerant cycle including an evaporator (154), in which the refrigerant absorbs heat from the recovered heat source and is evaporated before being discharged from the evaporator for compression by compressor (153) (fig. 3; paragraphs 0039-0041). It would have been obvious to one of ordinary skill in the art at the time of the invention to modify the shipboard waste heat recovery system of Kuwahata with the heat pump refrigerant cycle taught by Hwang in view of claim 1. Because for the evaporator to evaporate the refrigerant into gas having a humidity of 100%, as taught by Hwang, because evaporation inherently produces saturated vapor under equilibrium conditions, making the claimed humidity an expected and predictable result. MPEP 2112.
Regarding claim 15, Kuwahata discloses a waste-heat system method onboard a ship utilizing recovered engine waste heat (paragraph 0009), comprising: a recovering heat from engine jacket cooling water and suppling the recovered heat recovery heat exchanger for steam generation (paragraphs 0036, 0056) by using mid- temperature water (paragraph 0056). However, Kuwahata fails to disclose employing the recovered engine coolant within a closed-loop vapor-compression heat pump system or recompressing the generated steam.
Hwang discloses a complete heat pump refrigerant cycle (fig. 3) including: compressor (151), which compresses refrigerant (fig. 3; paragraph 0040); condenser (152), which transfers heat from compressed refrigerant to water ; evaporator (154), which evaporates refrigerant using recovered waste heat (paragraph 0039-0041); internal heat exchange (153), disposed between the condenser outlet and compressor inlet, configured to exchange heat between refrigerant leaving the condenser and refrigerant returning from the evaporator, thereby recovered heat from the refrigerant discharged from the evaporator before compression (fig. 3; paragraphs 0039-0041).
Lee discloses a steam production heat pump system including: a compressor (111) for compressing refrigerant (paragraphs 0021-0023); a condenser (112) configured to transfer heat from compressed refrigerant to circulating water for steam production (paragraphs 0023, 0031, 0047-0048); an internal heat exchanger / recuperator (115) disposed between the condenser outlet and compressor inlet for recovering heat from refrigerant returning from the evaporator while sub cooling refrigerant leaving the condenser (paragraphs 0006-0011, 0026); a steam generation cycle including flash tank (121) producing steam from heated water (paragraphs 0030-0032); a steam recompression or mechanical vapor recompression for increasing steam pressure and improving thermal efficiency (paragraph 0082).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify Kuwahata’s shipboard engine waste-heat recovery system by incorporating the vapor compression heat-pump taught by Hwang, and the mechanical vapor recompression system taught by Lee because each reference seeks to maximize recovery and utilization of otherwise wasted thermal energy. Incorporating Hwang’s heat-pump into Kuwahata’s shipboard waste recovery system increases utilization of engine jacket cooling water as a heat source, while incorporating Lee’s steam recompression increases the pressure and usefulness of the generated steam for downstream thermal applications. The combination employs known thermal recovery components according to their established functions to obtain the result of improved steam generation efficiency.
The recitation that the heat pump provides additional steam beyond that generated by a boiler and exhaust gas heat source defines the intended operational use of the combined heat recovery system and does not require a structural distinction over the cited combination. Once the known heat pump of Hwang is incorporated into Kuwahata’s waste heat recovery system, the heat pump necessary supplements the steam otherwise available from conventional waste heat recovery.
With respect to the recited engine coolant temperature of approximately 70oC to 90oC, Kuwahata discloses using engine jacket cooling water as the recovered heat source. Such temperature are conventional operating temperatures for marine engine jacket cooling systems and would have been an obvious operating condition for implementing the combined system.
With respect to the recited steam pressure of approximately 1.5 to 3 bar and recompression to approximately 3 to 5 bar, Lee expressly teaches increasing steam pressure through mechanical vapor recompression to improve steam utilization efficiency. Thus, Lee recognizes steam pressure as an operating parameter affecting system performance. Selecting particular operating pressures appropriate for a desired downstream steam application would have constituted routine optimization of a recognized result-effective variable absent evidence that the claimed pressure ranges are critical or produce unexpected results.
Response to Arguments
Applicant's arguments filed 04/09/2026 have been fully considered but they are not persuasive.
Applicant argues that amended independent claims 1, 8, and 15 define an integrated technical relationship among the evaporator, internal heat exchanger, compressor, condenser, and steam compressor that is not disclosed by the cited references. The rejection does not rely upon any single reference disclosing the entire claimed system. Rather, the rejection relies upon the combined teachings of Kuwahata, Hwang and Lee. Kuwahata discloses recovering engine waste heat aboard a ship, Hwang discloses the functional relationship among the evaporator, internal heat exchanger, compressor, and condenser within a conventional vapor-compression heat pump cycle, and Lee discloses recompressing the generated steam to increase steam stem pressure and improve thermal efficiency. Accordingly, the combined references disclose the claimed operational relationship, and Applicant’s arguments attack the references individually rather than addressing their combined teachings.
Applicant further argues that the rejection relies upon impermissible hindsight. The rejection is based upon the express teachings of the cited references and the knowledge of one of ordinary skill in the art. Each reference is directed toward improving recovery and utilization of thermal energy, and the proposed combination merely applies each reference according to its disclosed purpose to achieve the predictable result of improved steam generation efficiency.
With respect to amended claim 8, Applicant argues that the claim recites a specific method rather than the apparatus of claim 1 in method form. The recited sequence of supplying engine coolant to the evaporator, recovering heat through the internal heat exchanger, compressing the refrigerant, transferring heat through the condenser to generate steam, and recompressing the generated steam corresponds to the ordinary operating sequence of the combined vapor-compression heat pump disclosed by Hwang together with the mechanical vapor recompression process disclosed by Lee. Hence, the claimed method does not an operational sequence that patentably distinguishes over the combined teachings of the cited references.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/M.N.E./Examiner, Art Unit 1776 /Jennifer Dieterle/Supervisory Patent Examiner, Art Unit 1776
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