Assessing dripper clogging and filtering performance using municipal wastewater

Abstract

The paper discusses some drip irrigation system management problems according to the performance of emitters and filters shown in six trials conducted in Sicily (Italy) using six kinds of municipal wastewater that has not undergone previous advanced treatment. Nine types of filters (gravel media, disk and screen) and five types of drip emitters (vortex, labyrinth and long-path) were tested. The performance of the emitters and filters tested depends on the quality of the wastewater. Total suspended solids, BOD 5 and pH are the water characteristics best correlated to emitter and filter performance.The vortex emitters tested were more sensitive to clogging than labyrinth emitters. The optimal performance of the subsurface emitters shows the feasibility of drip subirrigation. The gravel media filters guaranteed the best performance. The disk filters, which are cheaper and simpler to manage, assured satisfactory performance in most trials. Screen filters were shown to be unsuitable for use with wastewater of poor quality. The need for frequent cleanings leads to short operating times for the filters, which may cause management problems. An empirical equation is proposed to estimate the frequency of filter cleaning operations depending on the solid discharge. Copyright # 2005 John Wiley & Sons, Ltd.key words: drippers; emitter clogging; filters; irrigation; water quality; wastewater RÉ SUMÉ Dans cet article il s'agit de quelques problèmes de gérer des systèmes d'irrigation à la goutte à goutte et de la performance des goutteurs et des filtres utilisant des eaux usées urbaines. Dans ce travail on discute de certains problèmes de gestion des installations d'irrigation localisée mis en relief par les résultats des six essais de goutteurs et filtres (réalisés en Sicile, Italie) avec six types différents d'eaux usées urbaines non-soumises à traitements avancés. On a essayé neuf types de filtre (à gravillon, à disques, à mailles) et cinq types de distributeur (à tourbillon, à labyrinthe, à long parcours). Les résultats des essais ont confirmé que la performance des distributeurs et des filtres dépend de la qualité des eaux; en particulier du contenu des solides suspendus, du BOD 5 et du pH. Les goutteurs à tourbillon essayés se sont révélés plus sensibles à l'occlusion que ceux à labyrinthe. L'excellente performance des goutteurs souterrains met en relief la faisabilité de l'irrigation souterraine. Les filtres à gravillon ont été ceux qui protègent mieux les goutteurs. Les filtres à disques, plus économiques et plus faciles à gérer, assuraient une satisfaisante performance des distributeurs dans la plupart des essais. Les filtres à mailles, au contraire, ne se sont pas indiqués à l'utilisation d'eaux usées de mauvaise qualité. Les très bas temps de fonctionnement de la plupart des filtres peuvent causer des problèmes de gestion. Les résultats des essais ont permis de formuler une équation empirique pour l'évaluation de la fréquence des opérations de nettoyage des filtres en fonction du débit solide.

A Tool for the Evaluation of Irrigation Water Quality in the Arid and Semi-Arid Regions

“…Soil microorganisms and nutrient conditions are influenced by pH value [25][26][27] and have to be considered as important parameter when microirrigation is used due to salts precipitation with consequent occlusion problems in the emitters and other components of the system [28,29]. Extreme pH values, especially influencing nutrients availability, affect crop growth and production [30][31][32][33].…”

Effects of Drip Irrigation Frequency on Emitter Clogging using Saline Water for Processing Tomato Production

“…Emitter clogging is affected by many factors such as irrigation water quality (Capra & Scicolone, 2005), emitter type , geometric parameters of the flow path , and irrigation operation mode (Hills et al, 1989). For a drip irrigation system using saline water, Hills et al (1989) analysed the effect of different management schemes on emitter clogging, and found that nightonly irrigation and subsurface irrigation failed to prevent chemical precipitation; lowering of the pH of the water gave the least clogging.…”

Effect of fertilization and sediment flow hydraulic characteristics on emitter clogging in muddy water drip fertigation system†

“…Additionally, the suspended particulate matter in the water is prone to physical flocculation with drip fertigation, which becomes a bridge between microbial growth and chemical adsorption. The composite clogging materials with higher stability will be formed by the catalysis effect of the microbes and salt ions, which results in emitter clogging (Capra and Scicolone, ; Gouider et al, ; Niu et al, ; Ahmed et al, ). Therefore, an investigation of water flow characteristics and sediment flocculation–deposition intensities and distribution patterns in the emitters was necessary.…”