Development of alternative systems for purifying water condensed by air conditioning units.

Abstract

Condensation water generated in air-conditioning equipment is a good alternative to drinking water for use in laboratory purification systems. The objective of this study was to evaluate the efficiency of removing inorganic contaminants from air-conditioning unit condensation water using low-cost filtration systems. Condensation water was tested in five systems (S1 to S5), whose performances were compared to a reverse osmosis system with deionizer. The materials used in the systems were: S1 = polypropylene filter, S2 = polypropylene filter + 102.00 g of zeolite, S3 = polypropylene filter + 400.00 g of zeolite, S4 = polypropylene filter + 400.00 g of zeolite + 68.83 g of mixed resin and S5 = polypropylene filter + 90.00 g of mixed resin (50% cationic and 50% anionic). The filtered water in each system was collected for pH, conductivity and quantification of analytes (calcium, magnesium, phosphate, nitrite, nitrate and ammonia nitrogen) measurements. The pH and conductivity ranged from 5.53 to 6.98 and from 3.47 μS cm^-1 to 20.2 μS cm^-1, respectively. Calcium, magnesium and nitrate were not detected; phosphate exhibited low concentrations, from undetected to 0.00755 mg L^-1 and; ammoniacal nitrogen presented concentrations from undetected to 3.71 mg L^-1. S5 showed the best overall performance, removing up to 100% of phosphate and 95.81% of nitrite, in addition to significantly reducing ammoniacal N (88.56%).