Compact Absorption Cooling Cycle Apparatus for Exhaust Gas Water Recovery

Supplying potable water to troops in the field is a significant hurdle requiring complex logistics and specialized equipment. Operational units already have an untapped source of water in the exhaust from their engines. The challenge is to efficiently cool the exhaust below the dew point and condense the water vapor. CFDRC proposes the development of the absorption cooling Diesel Exhaust-Water Recovery System (DEWRS). The system utilizes rejected heat in the exhaust gas stream to drive a thermodynamic cycle that cools the exhaust gas and condenses the water vapor. The cycle circulates liquid refrigerant, which provides the advantages of using a small pump, and offers flexibility in system arrangement. Parametric thermodynamic system analysis will examine the applicability of both LiBr/H2O and H2O/NH3 absorption cycles. A 1-D system model will be developed to simulate the engine-DEWRS integrated system operating under a variety of duty cycles. Additional detailed analyses will be performed to support the design of system components, including the use of Genetic Algorithms for optimization. During Phase 1, our efforts will focus on developing a prototype system compatible with the single cylinder Caterpillar (3400 Series) diesel test engine at the University of Alabama IC Engine Test Center.