Corrosão em fertirrigação por soluções de Ureia e Cloreto de Potássio em aço galvanizado e aço inoxidável 304

Abstract

Fertigation is an agricultural technique that consists on applying fertilizers through irrigation water. When compared to conventional fertilization method, it presents advantages such as saving time and labor. However, when diluting the fertilizer in irrigation water, it is possible that corrosion of the metallic components of the system is accentuated. In this study, the corrosion effects due to practice of fertigation with white Potassium Chloride (10 g L-1) and Urea (10 g L-1) solutions in galvanized steel and AISI 304 stainless steel specimens were evaluated, materials similar to those used in center pivots and injection pumps, when simulating the practice of 5 annual fertigation, lasting 7 hours each, for a period of 10 years. The experiment was carried out by means of immersion corrosion tests and the mass loss, the corrosion penetration rate and the estimated of the material useful life were calculated. The results allowed to verify that variation in fertilizer source as well as the type of metal, influence corrosion effects, however, the estimated useful life for the metallic components used in irrigation systems that practice or not fertigation, was practically the same