An automotive ammonia absorption refrigeration system comprising:
- a generator vessel in heat exchange relationship with at least one exhaust conduit from a vehicle engine exhaust system for heating refrigerant in said generator vessel by exhaust gas;
- first conduit means connected to said generator vessel for introducing into said generator vessel strong ammonia/water refrigerant solution returned from at least one absorber vessel;
- at least one refrigerant solution pump means having an outlet connected to said first conduit means and an inlet connected to said at least one absorber vessel, and having a minimum output capacity to produce at least a minimum of 260 psia operating pressure in said generator vessel;
- second conduit means connected to said generator vessel for removing ammonia vapor separated from said solution in said generator vessel;
- third conduit means connected to said generator vessel for removing weak ammonia/water solution residue from said generator vessel after ammonia refrigerant vapor has been separated from said strong ammonia/water refrigerant solution;
- an ammonia condenser vessel connected to said second conduit means for receiving ammonia vapor from said generator vessel at generator operating condition pressure, said condenser vessel being in heat exchange relationship with ambient air flow providing cooling to carry off at least the combination of vapor superheat and latent heat of condensation rejected from ammonia vapor in said condenser vessel to effect condensation of the ammonia vapor to the liquid phase thereof;
- fourth conduit means for delivering condensed liquified ammonia refrigerant from said condenser vessel to an inlet of at least one evaporator pressure-reducing valve;
- at least one evaporator pressure-reducing valve connected to said fourth conduit means for reducing pressure of the liquid refrigerant entering from said condenser vessel to saturation pressure of ammonia at the desired refrigerating temperature;
- at least one evaporator vessel for containing said refrigerant in heat exchange relationship with coolant fluid to be refrigerated by absorption of the heat of vaporization of ammonia liquid from said coolant fluid;
- fifth conduit means connecting said at least one evaporator pressure reducing valve to said at least one evaporator vessel for supplying liquid ammonia refrigerant at said reduced pressure to said at least one evaporator vessel;
- a first inlet in said at least one evaporator vessel into which reduced pressure ammonia from said at least one evaporator pressure-reducing valve is admitted via said fifth conduit means;
- a first outlet in said at least one evaporator vessel through which ammonia vapor produced therein exits said at least one evaporator vessel;
- sixth conduit means connected to said first outlet in said at least one evaporator vessel;
- at least one absorber vessel having a first inlet connected to said sixth conduit means for admission of ammonia vapor from said at least one evaporator vessel, and a second inlet connected to said third conduit means for admission of said weak water/ammonia solution from said generator vessel through an at least one absorber pressure-reducing valve, so that said at least one absorber vessel mixes the two fluids therein at a common pressure, said at least one absorber vessel being in heat exchange relationship with a flow of ambient air adequate to remove heat energy evolved as a result of loss of specific heat of said ammonia/water solution rejected as its temperature lowers, the heat of mixing evolved as ammonia vapor enters solution in said weak ammonia/water solution, and the latent heat evolved as ammonia vapor assumes a liquid phase condition in the evolving strong ammonia/water solution formed in said at least one absorber vessel, the contents of said at least one absorber vessel being operated at a pressure consonant with the associated evaporator pressure;
- seventh conduit means connected to said at least one absorber vessel for conducting strong aqua solution from said at least one absorber vessel to said at least one solution pump means so that said at least one solution pump means pumps the strong aqua solution formed in said at least one absorber vessel to said generator vessel at said pressure not less than 260 psia;
- means for driving said at least one refrigerant solution pump means;
- coolant circuit means for conducting said coolant fluid through said at least one evaporator vessel for cooling said coolant fluid therein and through a comfort zone cooling means in a comfort zone at one temperature and through a cargo storage zone cooling means in a cargo zone for cooling cargo therein at a second temperature lower than said comfort zone temperature;
- and control means for safe operation of the system and maintaining intended operating pressures and temperatures in the system.