Chloride is a deleterious ionic species in cooling water systems because it is important in promoting corrosion. Chloride can be removed from cooling water by precipitation as calcium chloroaluminate using ultra-high lime with aluminum process (UHLA). The research program was conducted to study equilibrium characteristics and kinetics of chloride removal by UHLA process, study interactions between chloride and sulfate or silica, and develop a model for multicomponent removal by UHLA. Kinetics of chloride removal with UHLA was investigated. Chloride removal was found to be fast and therefore, removal kinetics should not be a limitation to applying the UHLA process. Equilibrium characteristics of chloride removal with UHLA were characterized. Good chloride removal was obtained at reasonable ranges of lime and aluminum doses. However, the stoichiometry of chloride removal with UHLA deviated from the theoretical stoichiometry of calcium chloroaluminate precipitation. Equilibrium modeling of experimental data and XRD analysis of precipitated solids indicated that this deviation was due to the formation of other solid phases such as tricalcium hydroxyaluminate and tetracalcium hydroxyaluminate. Effect of pH on chloride removal was characterized. Optimum pH for maximum chloride removal was pH 12 ± 0.2. Results of equilibrium experiments at different temperatures indicated that final chloride concentrations slightly increased when water temperature increased at temperatures below 40oC. However, at temperatures above 40oC, chloride concentration substantially increased with increasing water temperature. An equilibrium model was developed to describe chemical behavior of chloride removal from recycled cooling water using UHLA. Formation of a solid solution of calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate was found to be the best mechanism to describe the chemical behavior of chloride removal with UHLA. Results of experiments that studied interactions between chloride and sulfate indicated that sulfate is preferentially removed over chloride. Final chloride concentration increased with increasing initial sulfate concentration. Silica was found to have only a small effect on chloride removal. The equilibrium model was modified in order to include sulfate and silica reactions along with chloride in UHLA process and it was able to accurately predict the chemical behavior of simultaneous removal of chloride, sulfate, and silica with UHLA.

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Stress is associated with a vast array of negative outcomes for both physical and mental health. Based on evidence that stress influences temperature, and that psychology and physiology influence each other, we investigated the novel possibility that reducing brain temperature reduces stress in a sample of 91 university students. We used head fanning to reduce brain temperature and measured this change with an infrared ear thermometer. Participants were randomly assigned so that the fans faced toward half of the participants (cooling condition) and faced away from the other half (non-cooling control condition). Differences in stress between conditions during the Vandenberg and Kuse (1978) Mental Rotations Test were then examined to test the hypotheses that (a) cooling would buffer stress and (b) that this would be mediated by changes in brain temperature, as indicated by ear temperature. Participants in the cooling condition were less stressed (p = .02) and also performed better (p = .03) during the task but neither of these findings were mediated by ear temperature. Thus, some uncontrolled variable(s), and not changes in temperature, may have been responsible for the effect of cooling on stress. Alternatively, error in measuring brain temperature may have obscured the hypothesised causal relationship between temperature and stress. More research is needed to confirm whether cooling the head is a simple way to manage stress.

To determine the effects of torso cooling with ice (ICE) or water-perfused (WP) vests during rest and warm-up on subsequent 1500 m time trial rowing performance in the heat. Eight male rowers (23 ± 4 y) completed 3 sessions on an ergometer in an environmental chamber (38ºC, 47% RH) 1 week apart. Pre-cooling was applied during rest (45 min) and warm-up (30 min) in 2 trials using ICE or WP vests, but not in the control condition (CON). Rectal (Tre) and skin (Tsk) temperature, HR, RPE, thermal comfort (TC) and sensation (TS) were monitored throughout. HR, RPE or TS were not different between conditions. TC, Tre and Tsk were lower in WP and ICE than CON post warm-up (P<0.05). The reduction in strain was reflected by increased power output during the 1500 m time trial in ICE (11±1.2 %) and WP (9.6±1.1%) compared to CON (P<0.05). Pre-cooling with ICE or WP vests enhanced performance in a 1500 m rowing time trial and power output was higher from the onset.

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