EFFECT OF HYDRAULIC PROPERTIES OF FILTER MEDIA ON THE DESIGN OF TRICKLE IRRIGATION NETWORK

Abstract

Series of laboratory experiments were conducted to investigate the filtration performance of different types of filter media. These experiments were divided in two main parts. The first one was to determine some physical and chemical properties of five different foreign and local media types. The second was to evaluate the filtration performance of each media type under different operating conditions of sedimentation loads and filtration depths. Emitter clogging problem under these different operating conditions was investigated. Five different emitter types were also used. The statistical split-split- split plot design was chosen for this study. A mathematical model was developed to simulate the trickle irrigation performance under different operating conditions. Experimental results were employed to verify the model prediction accuracy and to test its sensitivity. Summary of the obtained results is given as follows: A. Laboratorv experiments. 1. The coefficients of permeability (k) are strongly related to the grain effective diameter (010) and the porosity of the filter media. • 2. Media size is the main factor affecting removal efficiency and pressure loss development. 3. Sedimentation loads are the second most important factor affecting the media filter performance. Generally removal efficiency decreased with increasing the sedimentation loads. 4. An improvement of the removal efficiency due to increasing filter bed depth from 30 to 50 em was noticed.