Aqueous Absorption Fluids. Final Report, July 1987-May 1992

摘要

Seven candidate absorption fluids were investigated experimentally and three werefound to have potential absorber temperature gains in the range of 7 C (13 F) to 15 C (27 F). LB621 (code name for a particular salt/organic pair) was selected as the single primary candidate working fluid. The equilibrium vapor pressure and specific heat capacity of LB621 solutions were measured as a function of temperature and concentration, and were used to compute the enthalpy of LB621 solutions. A failing film test sorber was constructed, and measured solution film heat transfer coefficients. A dramatic increase in film heat transfer was found in the presence of heat transfer additives. Measured equilibrium and film heat transfer data were used in the single-stage absorption cycle computer model to analyze the potential performance of LB621; the analysis confirmed the superiority of LB621 as a single-stage working fluid. Thermal stability and corrosion rate tests demonstrated that LB621 is stable and non-corrosive in a single-stage absorption chiller environment. Two fluids, LB601 and LB611 show good stability at the higher temperatures of two-stage equipment, while LB621 was not stable. Headspace GC-MS analysis did not find significant evolution of volatile decomposition products.