Anaerobic digestion effluents for corn and sunflower production in Mexico

Abstract

Anaerobic digestion is an alternative for wastewater treatment and its effluent could be used in agricultural production because it may contain nutrients; however, its harmlessness is a limiting factor. This research evaluated the potential of a self-cleaning biodigester (SCB) effluent to increase corn and sunflower production of a school plot. The SCB was located at the Telebachillerato Comunitario in San Felipe del Progreso, State of Mexico, Mexico. A randomized block design was used with three fertilization levels of N, P and K, irrigated with SCB effluent and potable water and 3 replications. Physical, chemical and biological parameters (total and fecal coliforms, Salmonella and Escherichia coli) were evaluated in the SCB effluent before being used as fertilizer on the corn and sunflower crops. Finally, the grain yield and the harvested seeds' safety were determined. In the SCB effluent, high K and Ca, high salinity, moderate total coliforms, fecal coliforms and E. coli were observed; Salmonella was not detected. In corn and sunflower seed, 98% of total coliforms were reduced, with no presence of fecal coliforms and E. coli compared to the SCB effluent. The grain yield of sunflower irrigated with SCB effluent increased up to 72% compared to that irrigated with potable water and in corn no significant differences were found between SCB effluent and potable water irrigation.

Keywords

• anaerobic digestion
• biofertilizer
• treated wastewater
• innocuousness