Medição de turbidez de água a partir de imagens processadas por eletrônica digital embarcada

Abstract

Water is an essential substance for human life, whether in hydration purposes, as ingestion and preparation of food, in industry, in agriculture, as well for simply recreation. Due to its importance, it is fundamental to evaluate its quality, since a poor quality water can results in health risks when consumed. Many localities in Brazil still do not have access to treated water, especially in regions away from urban centers. Knowing this, technological innovations related to water treatment for small stations are being developed, that way, residents of areas far from urban centers can also use good quality water. In order to contribute to society, in the present work, a water quality monitoring system was implemented, consisting of turbidity meter that uses digital electronics boarded through arduino board, for the opening and closing valves control, aiming automatic water samples collecting, besides processing and converting the luminous intensity of images to a turbidity scale, with a cost of R$ 450.00, much lower than the traditional process meters found in the market, reaching values up to R$ 28,890,00. The work was carried out in the Engineering Department of Federal University of Lavras and in the Water Treatment Plant of the Federal University of Lavras (ETA / UFLA). It was observed that samples with clay and granule-soluble coffee, both dissolved in mineral water, presented different behavior in calibration curves of the equipment, showing that raw water samples from ETA/UFLA calibration was necessary. The developed device showed good efficiency in the turbidity measurement, obtaining good precision in a range of less than 1 to 1000NTU, range of value within the parameters for consumption, according to the World Health Organization.