Filtração lenta retrolavável utilizando carvão antracito como meio filtrante para aplicação em comunidades rurais

Abstract

Slow backwashable filtration is an efficient technology for treating water for human consumption in small rural communities without access to potable water. Through said filtration, it's possible to modify some physicochemical characteristics to make it suitable for consumption. To this end, a proper study dimensioned and built a prototype of a slow backwashable filter aiming at treating water from a small dam located on the Campus itself. The filtration system used anthracite coal as the filtering medium. The research included evaluating the entire pilot system considering operational hydraulic aspects, such as the expansion of the filtering medium and the efficiency of backwashing. Water quality parameters in terms of turbidity, apparent color, true color, dissolved oxygen, temperature, electrical conductivity, and absorbance at 254 nm were also assessed. The hydraulic performance of the system was monitored through the head loss across the filtering medium. The total operating time of the system was 88 consecutive days, generating 5 filtration runs. The system proved effective in terms of head loss and expansion of the filtering medium during the cleaning process. However, the evaluation of backwashing still revealed insufficient cleaning time for the system's application. Turbidity emerged as a parameter with significant potential, although it did not meet the standards of current legislation. Overall, the analyzed parameters indicated deep filtration, with an indication of high microbiological activity along the filtering bed. Nonetheless, the system proved to be a significant ally for supplying small, isolated communities, even while presenting parameters that don't comply with regulations. There is a possibility of further study development and system improvement, as well as the use of allied technologies such as pretreatment and disinfection systems. Ultimately, it's understood that this system has great potential if operated properly and if studies on the technology and its application area are developed, aiming to provide access to potable water for the entire population, especially rural communities.