Determination of acid requirement for preventing chemical clogging in a drip irrigation system

Abstract

Problem of clogging is frequently observed in emitters of drip irrigation systems, which is directly linked with quality of water and effectiveness of filtration system. Acidification can reduce biological as well as chemical clogging of emitters as it reduces pH of water. In this study fifteen water samples collected from different locations having diverse quality parameters with their pH ranging between 8.14 to 9.26 were used. From these samples 50 ml of solution was taken and pH of the water sample was reduced to a desired level (=4) by titrating it against three different acids HCl (35.5% conc.), H2SO4 (98.8% conc.) and H3PO4 (88% conc.). Acid solutions of 0.01N were prepared to determine the amount of acid require to lower down the pH to a target level (4.0). Functional relationships were developed to determine the amount of different acids required for bring down pH 1000 litre of water to a desired level (4.0). It was found that the amount of HCl, H2SO4 and H3PO4 required to bring down the pH of water sample has a strong correlation with initial pH. The effect of other water quality parameters on acid requirement is found to be non-significant. Among HCl (35.5% conc.), H2SO4 (98.8% conc.) and H3PO4 (88% conc.), the phosphoric acid is most economical to use for acidification treatment.