Fluides de réfrigération

The present work investigates equilibrium conditions and dissociation enthalpies of semiclathrate hydrates formed from CO2 – tetra-n-butylammonium chloride (TBACl) – water, CO2 – tetra-n-butylammonium nitrate (TBANO3) – water and CO2 – tetra-n-butylphosphonium bromide (TBPB) – water mixtures. Differential scanning calorimetry (DSC) was used for the determination of hydrate-liquid-vapor (H-L-V) equilibrium conditions in the presence of [...]

Tetra-n-butyl ammonium bromide (TBAB) semi-clathrate (sc) hydrates of gas are of prime importance in the secondary refrigeration domain and in the separation of gas molecules by molecular size. However, there is a
scarcity of dissociation enthalpies under pressure of pure gases and gases mixtures for such systems. In addition, the phase equilibrium of TBAB sc hydrates [...]

Clathrate hydrate slurries are promising systems in the field of cold distribution. In this work, the Lw-H-V equilibrium conditions, the dissociation enthalpy, and the CO2 hydration number of a clathrate hydrate formed from THF/CO2/water mixtures were studied, using a DSC method. For equilibrium condition determination, THF concentration was varied from 1.0 to 16.0 wt % [...]

The present work investigates the formation conditions and the latent heat of dissociation of hydrates formed
from tetrahydrofuran (THF)-CO2-water mixtures. The conditions investigated are 3.8-15 wt % for THF concentration and 0.2-3.5 MPa for the CO2 partial pressure range, conditions that are adapted to the use of the corresponding hydrate slurries as secondary refrigerants. Both differential [...]

The present study investigates the suitability of CO2 hydrate for a use as phase change material in two-phase secondary refrigeration. Unlike the generation of the classical two-phase refrigerants, power limited by mechanical parts, hydrate slurry production has the advantage of being performed using a nonmechanical process. Nevertheless, in order to be efficient, the hydrate slurry [...]