Viabilidade técnica, econômica e ambiental no reaproveitamento da água de lavagem de ETAs - estudo de caso ETA de Gravatá - Campina Grande-PB.

Abstract

The water lost occurs in ali supply system, since the cotching until the distribuition. In water treatment plant (WTP), the lost, in the most part related the operations water amount used in the process of treatmente and throuwn away in the environment without reuse.The water reuse technology is based in a new concept which says the water, after being used, shouldn't be discarded, and through a proper treatment it would have a use. The recycling of wash water is an alternative the WTPs is an alternative which has been used with the aim to reduce the lost of water that occurs in the process of the water treatment. This choice can become a solution to water scarcity problems and of environmental impacts. With this purpose, this paper is focused on studying the technique, economic and environmental viability in the reuse of washing water at the WTPs, especially the Gravata Water Treatment Plant (WTP) which provides for Campina Grande City - Paraíba, The presented alternatives were: Installing either a new sedimentary with a drying place, a sedimentary with a couple of iodine lagoons or three iodine lagoons. In the initial developed methodology, the washing water was analyzed, in order to evaluate the retuming conditions to the WTP. We estimate the amount wasted in the washing process by adding the amount wasted with the evacuation to the one wasted cleaning the treatment units. In order to reach an appropriate alternative we compared them through a study about the technique, economic and environmental viability. For study technique viability considered the aspects relative operational conditions and efficiency of pilot project of system of recycling. The study of the economical quantification of ali benefits and costs involved in the system of recycling washing water in WTP. In investigation of viability environmental was the identification of impacts introduction residuais the processes used in treating water of WTP in environmental The amount of water to be recovered monthly at the WTP was at about 2.08%, which represents 20.0 liters/second, it's enough to provide an 8,519 people population with a per capita of 200 liters/inhabitant/day. The reuse of water amount can bring benefits to the enterprise in charge of the water treatment and providing, it will improve finance, and part of the water won't be thrown into the receiving bodies, well as the other part won't be caught, which protect the environment and maintain the water availability of the fountainhead.