FURTHER RESEARCH OF PARTIAL HYBRID COMPRESSION TECHNOLOGY APPLIED TO ULTRA-LOW TEMPERATURE REFRIGERATION AND HYDROGEN LIQUEFACTION

The concept of Hybrid Compression (HC) is a two-technology synergy, introduced lately by the author. It aims at improving the feasibility of heat pumping applications, mainly in ultra-low temperature refrigeration (ULTR) and ultra-high temperature heating (UHTH), (Staicovici, 2015 a, b, c, 2016 a, b, 2017 a). The synergy technologies lay down the operation of an Absorption Technology Section (ATS) and a Mechanical Vapor Compression Technology Section (MVCTS), so that MVCTS plays the role of sink and heat or just the heat source for ATS, while ATS performs the useful task of cooling or heating, respectively. Recently, HC was completed with the Partial Hybrid Compression (PHC). PHC benefits of a free heat source heating of ATS generator-rectifier. This work presents further PHC-ULTR research and its application. PHC-ULTR results are given for single-stage NH3-H2O ATS and NH3 two-stage MVCTS using TWRC (Staicovici, 2014). Input temperatures data are: a) evaporator, TDI = -75, -70,..., -45 degrees C; b) external sink, T-Ess = -18, -9, ..., +45 degrees C; c) internal sink, T-MC = -35, -30, ..., +5 degrees C. Main output data are: i) PHC cooling effectiveness, COPc,PHC and ii) ATS generator temperature, T-Mh. The (i) output data show highest COPc,PHC, which increase PHC-ULTR feasibility. After two former studies, of air and natural gas liquefaction (Staicovici, 2017 a, b), in last section PHC-ULTR is applied again to an important cryogenic topic, concerning this time the hydrogen liquefaction (HL). Similar to the former studies, PHC-ULTR shows promise this time in HL cryogenics.