NATURAL WASTEWATER TREATMENT IN MOUNTAIN AREAS IN LEBANON

Abstract

One of the most important stages and energy intensive operations at the wastewater treatment plant is the aeration. Several researchers have conducted laboratory works to investigate the aeration efficiency of stepped cascades. The proposed study consists of taking advantage of the hilly topography of Lebanon mountains for natural wastewater treatment by creating stepped cascades, without using any types of costly equipment that may further result in additional air emissions the environment. In this paper, the natural land formation of one of the mountains in Lebanon is shaped as a stepped cascade and the aeration efficiency was measured and compared to mathematical models prepared by Gameson et al., WRL, Nakasone & El-Monayeri. The use of fixed film bacteria has been also investigated. Good agreement between the site measurements and the models that account for the flow rate & cascade geometry was obtained. The results indicate that the stepped cascade and the fixed film bacteria contribute to the improvement of wastewater characteristics.