Analyzing Granular and Membrane Filters for Rainwater Treatment: A Comparative Study

Abstract

The aim of this research was to evaluate the effectiveness of rainwater treatment using two distinct filtration methods: one utilizing traditional filtration materials (gravel, sand, and anthracite), and the other employing membranes. In both cases, the quality of the treated rainwater met the standards set by NBR 15527:2007 (Brazilian Association of Technical Standards) and the United States Environmental Protection Agency (EPA) for non-potable purposes, including parameters such as pH, temperature, turbidity, ammonia, nitrate, nitrite, alkalinity, and calcium hardness. Furthermore, the findings were compared with Brazilian Ministry of Health Directive 2914/2011, which pertains to water potability, and Resolution 357/2005 of CONAMA (Brazilian National Council for the Environment), addressing surface water bodies, particularly rivers, and permitting direct human skin contact with water. The study concluded that rainwater treated by both filtration methods could be utilized for various non-potable applications such as toilet flushing, garden irrigation, and sidewalk 
cleaning, as well as for direct-contact activities like bathing and laundry washing.