Estabilidad de un digestor anaerobio termófilo en condiciones no habituales de operación

Abstract

This study investigate the stability of a thermophilic anaerobic digester (55 ° C) in unusual operating conditions treating sludge produced in a wastewater treatment plant, with an average composition : COD 30,000 mg / l; SV 20 g / l; pH 8.0; N-NH3 272 mg / l; N-NKT 1811 mg / kg. The aim was to transform a thermophilic anaerobic methanogenic reactor into an acidogenic one. It was proposed to work by modifying the hydraulic retention time (progressive reduction from 23 to 4.5 days) by increasing the feed flow rate, accompanied with the subsequent raise in the values of organic loading rate. The results showed that these increases in the reactor loading were tolerated and the methanogenic behavior cannot be transformed into acidogenic, as indicated by average methane productivity around 5.19 l / d and SV removal of 37%.