Avaliação da eficiência de tratamento de gás odorante por meio de ensaios da intensidade de odor e análise físico-química.

Abstract

The odours are released from many industrial activities. Among these activities are included oil refineries, which despite being important source of energy and raw material available to man, this kind of activity brings together several effects related to odours, and consequently, air quality. This study aimed to evaluate, through equipment for treatment of gases in a pilot scale, the aeration as an alternative of treatment of odorous gaseous compound of synthetic effluent simulating effluents from petroleum refinery wastewater station. Using as an indicator of the efficiency of treatment the test of intensity of odour. The experiment was conducted on 2 pilot reactors of 4 litres, similar to batch reactors, in which were put 3 litres of synthetic effluent while 1 litre was left as "headspace" to contain the gases. The flow of air occurred with the use of aerator, with capacity for air flows rate of 20 L.min-1. In the system were observed the parameters time, loads of oxidation and types of diffusers. The evaluation of treatment was made by means of testing the intensity of odour, and physical-chemical analysis. In the experiment were used different loads of oxidation (a variation of scale of 36,48 and 72 Lar.Lefluente-1) evaluated in time periods of 4 and 8 hours for two types of diffusers (jet of air and porous). Among the results obtained in the aeration, it was observed that the load of oxidation which showed more process efficiency was the one of 72 Lar.Lefluente-1 during the period of 8 hours, due to 75% and 92% of the body of jurors have indicated a scale of intensity of odour very weak for this load of oxidation, for the jet air and porous diffusers, respectively. While the physical-chemical analysis was possible to determine the percentage of efficiency of the proposed process, obtaining 63.71% and 76.23% for the oxidation charge of 72 Lar.Lefluente-1 for the jet air and porous diffusers, respectively. The results obtained with the intensity of odour, expressed as an index of intensity and the concentration level of the content of hydrogen sulfide gas have helped to set the correlation point for these two parameters, achieving the correlation coefficients of 0.99 and 0.82 for the different types of diffusers. That way, before the results determined in this work, it is concluded that the test of odour intensity and physical-chemical analysis are crucial in assessing the efficiency of treatment of compound gases.