Effects of Orifice Size on Microsprinkler Clogging Rates

Abstract

The clogging rates of microsprinkler emitters with orifice diameters of 0.76 mm (0.03 in., black base), 1.02 mm (0.04 in., blue base), 1.27 mm (0.05 in., green base), and 1.52 mm (0.06 in., red base) were evaluated in a citrus grove over a three-year period. The experiment used a randomized complete block design with eight emitters per plot and five replications of each treatment. The irrigation water was drawn from a pond, treated with one of two water conditioners, and filtered through a sand media filter. Every three months, each emitter was inspected and those that were clogged were examined to determine the cause of clogging. All fouled emitters were thoroughly cleaned and/or replaced. Overall, 46% of the clogging was due to algae, 34% was from ants and spiders, 16% was from snails, and 4% was from physical particles such as sand and bits of PVC. About 20% of the black base emitters required cleaning or replacement during each quarter compared to about 14% of the blue base, 7% of the green base, and 5% of the red base emitters. The total clogging rate was found to be inversely related to the orifice area of the emitters during the three-year study.