Reúso de águas cinzas para fins não potáveis: estudo de caso UTFPR - Câmpus Londrina

Abstract

Gray water recovery systems are alternative sources for water demands. They are considered as an option to reduce water consumption, effluent generation and supply costs. In addition to being linked to the concept of environmental sustainability, these systems can also be used as instruments to regulate supply and demand for water resources, as demand for supply is increasing. This paper therefore presents a study of physical-chemical and microbiological characteristics of wastewater produced in the laboratories of a building of the Federal University of Technology – Paraná, Campus Londrina. This work research feasibility for non-potable purposes when used in the rainwater harvesting system. Wastewater samples were analyzed in the Sanitation and Microbiology Laboratories of the FUT-Paraná with methodologies of the Standard Methods for Water and Wastewater Examination (2012). The results indicate that the Block K laboratories wastewater system, associated with the building's rainwater harvesting system, has physical, chemical, microbiological and economic potential viability, capable of fundamental wastewater actions. The values of pH, total solids dissolved, total solids suspension, total phosphorus, nitrate, nitrite, ammonia nitrogen are actually accepted by the recommendation for water reuse in the toilet system. Analysis of total solids and total nitrogen Kjeldahl recorded values after rainwater reservoir compatible with the proposed reuse. Turbidity, DBO5,20 and volatile solids have slightly higher minimum values; however, the use of an oxidizer for tablet disinfection allows the residue to be viable. The potential economic value to be saved by the educational institution was approximately R$ 682,00 per year for a block of UTFPR-LD. Thus, can be possible to reuse with safety, without prejudice or damage equipment and users health, adopting a constant monitoring. Work of this nature is very important as it includes subsidies for future projects, contributes as institutions for optimizing the use of natural resources, supports as water reuse technologies and can contribute to ensuring availability and management of water and sanitation.