As discussed in the Liquid Desiccant Tutorial, both our Water-Cooled Conditioner and evaporatively-cooled conditioner use low-flow liquid-desiccant technology to eliminate carryover of desiccant droplets.  Both types of conditioners actively cool the core of the conditioner so that the process air is simultaneously dried and cooled.

Our evaporatively-cooled conditioner operates similarly to an indirect evaporative cooler.  The core of this conditioner is a plastic parallel-plate cross-flow heat exchanger.  As shown in the neighboring drawing, the air that is to be cooled and dried flows horizontally through one set of passages and the cooling air flows upward through the alternate set of passages.  Water is sprayed onto the walls of the cooling-air passages and a solution of lithium chloride is delivered to the walls of the process-air passages.  As the process air comes in contact with the desiccant, the water vapor in the air is absorbed.  This releases heat, which is immediately transferred to the cooling air.  The process air leaves the conditioner both drier and at a lower enthalpy. 

We completed laboratory tests of a 6-plate model of our evaporatively cooled conditioner in 2002.  As shown in the following picture, the model was composed of thermoformed plastic plates that have an active surface area 2 feet high by 3 feet wide.  Both the spacers for keeping the plates of the conditioner parallel and the desiccant distributor are thermoformed features of the plates.

A conditioner with a entrance face area of 2 feet by 2 feet will process 1,250 cfm.  When operating at the nominal air flow, this conditioner will process ventilation air from 86^oF and 133 grains to 86.5^oF and 30 grains--a reduction in enthalpy of 16.1 Btu/lb of processed air or about 7.5 tons total cooling. 

The pressure drop through the conditioner will be about 1.2" w.c for the process air.

U.S. Patent No. 6,848,265, which was issued to AILR in February 2005, covers the technology for the evaporatively cooled conditioner shown in the preceding picture.  AILR plans to commercialize this conditioner following the successful introduction of our Water-Cooled Conditioner.