Relação entre concentração de sólidos suspensos e turbidez da água medida com sensor de retroespalhamento óptico.

Abstract

Turbidity is a measure of water quality corresponding to the reduction in the transparency of the liquid medium, it is promoted by the suspended material, thus obstructing the passage of sunlight by water. The particle size may directly interfere with turbidity therefore smaller particles remain in suspension while larger tend to gradually settle. For prevent the passage of sunlight, water with high turbidity favor evaporative demand. Furthermore, the turbidity can also interfere in the aquatic environment. Thus studies that support the measurement of same are of fundamental importance. Turbidity measuring nephelometric turbidity based on the backscattering of light. However, the manufacturer recommends a calibration of these instruments with sediment samples from the site to be studied to minimize possible errors, and thus enabling correlate turbidity measured with the concentration of suspended solids (CSS). However, the difficulty in getting the material is kept in suspension is an obstacle in the calibration of these instruments. In this context, this study aimed to calibrate two turbidity of optical backscatter, with the aid of electromechanical shaker designed and built for this purpose. Furthermore it verified the influence of the different size fractions (sand, silt and clay) in turbidity rates. Obtained these studies, mathematical models with a high coefficient of determination, furthermore observed that the present optical backscatter turbidity faster response for the particles of smaller diameter.