Performance analysis of ionic liquids for simultaneous cooling and heating absorption system. (15th May 2023)

• Record Type: Journal Article
• Authors: Park, Sejun; Choi, Hyung Won; Lee, Jae Won; Cho, Hyun Uk; Lee, Nam Soo; Kang, Yong Tae
• Is Part Of: Energy. Volume 271(2023)
• Publication Date: 2023-05-15
• Subjects: Absorption system -- Coefficient of performance -- H2O -- Ionic liquid -- R32 -- Simultaneous cooling and Heating; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2023.127005
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: A new working fluid for simultaneous cooling and heating absorption system, which is a combination of type 1 and type 2 absorption systems, was analyzed by simulation analysis. An imidazolium-based ionic liquid (IL) was used as an absorbent in the new working fluid and H2 O and R32 were used as refrigerants. The states of the solution mixed with the refrigerant and absorbent were predicted using a non-random two-liquid (NRTL) model. The ILs with H2 O refrigerant were 1, 3-dimethylimidazolium dimethylphosphate ([DMIM][DMP]), 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM][DMP]), and 1-ethyl-3-methyl tetrafluoroborate ([EMIM][BF4 ]), and the IL with R32 refrigerant was 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][Tf2 N]). Changes in the cooling, heating, and total coefficient of performances (COPs) according to the generation temperature and generator and condenser split ratios were analyzed. It was concluded that H2 O/[DMIM][DMP], H2 O/[EMIM][DMP], and H2 O/[EMIM][BF4 ] were suitable for simultaneous cooling and heating absorption systems with reasonable cooling, heating and total COPs. However, R32/[HMIM][Tf2 N] had advantages for subzero cooling temperature and compactness of system size, while its COPs were lower than those of H2 O/[DMIM][DMP], H2 O/[EMIM][DMP], and H2 O/[EMIM][BF4 ]. The total COP of H2 O/[DMIM][DMP] was 0.98, indicating the highest performance. H2 O/[EMIM][DMP] and H2 O/[EMIM][BF4 ] exhibited total COPs of 0.96 and 0.97, whereas R32/[HMIM][Tf2 N] showed a value of 0.55, under certain simulation conditions. Highlights: Performance analysis of simultaneous cooling and heating absorption system is conducted. Using novel working fluids, weaknesses of absorption system can be solved. H2 O/[DMIM][DMP], H2 O/[EMIM][DMP] and H2 O/[EMIM][BF4 ] are suitable for the absorption system. Using R32/[HMIM][Tf2 N], the absorption system can be more compact. H2 O/ILs show 0.96–0.98 maximum COP while R32/IL does 0.55 maximum COP.