ADVANCES IN HYBRID COMPRESSION TECHNOLOGY FOR ULTRALOW TEMPERATURE REFRIGERATION ACHIEVEMENT

摘要

The Hybrid Compression (HC) technology, a synergy between an Absorption Technology Section (ATS) and a Mechanical Vapor Compression Technology Section (MVCTS), was successfully proposed recently for refrigeration and heating, Staicovici (2015a, b, c). In this work, HC advances in the ultra-low temperature refrigeration (ULTR), with emphasis in freeze drying applications, are disclosed. Two types thereof are in research. Both have the same ATS, but different MVCTS’s: a) 2 to 4 stage with discharge gas superheating recovery (TWRC, (Staicovici, 2014)) (HC1), and b) improved HC1 model (HC2). HC1 and HC2 are compared to a standard, 2 to 4 stage and interstage cooling, MVC unit. The MVC, HC1 and HC2 model considers NH3- H2O and NH3, seven evaporator temperatures, T_E = ?75, ?70, ..., ?45 °C, three sink source temperatures, Tss = 27, 36, and 45 °C, and four HC technology most relevant parameters: ⅰ) MVCTS maximum discharge gas temperature, T_(CpO); ⅱ) refrigeration coefficient of performance (COP); ⅲ) MVC vs. HC comparative compressed refrigerant volume, RV, and iv) exergy efficiency,η_E . Results show outstanding comparative HC vs. MVC and absolute values of ⅰ)-ⅳ) parameters, for same Tss and TE: A) HC1 and HC2 are compatible with today compressor operation, because T_(CpO) are smaller by 50 to 170 °C than those of MVC; B) HC COP’s are much higher than those of MVC, especially in the T_E= ?75 to ?60 °C domain, e.g. by 43 to 65 %; C) HC reduces R_V by 2.5 to 8 times as compared to MVC, promoting compressor physical size reduction; D) HC η_E ? has very high values, 0.62≤η_E≤ 0.78;E) The HC2 COP, R_V and η_E values are better than those of HC1.