Cooling Tower Drift Measurements Using Intrinsic Tracer H3BO3

Abstract

Several methods used to measure cooling tower drift emissions require isokinetic sampling of the air exiting the tower. The drift is obtained by analysing suitable tracers either added to the water flowing into the tower or naturally presents in the system. The former method is the most common and involves the measurement of conductance of sampled water in relation to circulating water, neglecting any possible external contamination affecting measurements. Our method uses H3BO3 as an excellent intrinsic tracer unaffected by the mixing of the external air with the water in the tower. Moreover, the presence of H3BO3 in all geothermal fluids and analytical detection limits for Boron with conventional spectroscopic techniques guarantee the reliability of this new method. A specific isokinetic sampling device, allowing sampling without warming the probe has been developed. The results of field tests are illustrated and compared with cooling tower manufacturer measurements, providing evidence of the wide applicability of this method.