Influência do inóculo no tratamento anaeróbio de resíduos sólidos orgânicos em regime batelada

Abstract

The choice of inoculum for treatment of organic solid waste is of the most importance to allow increased efficiency of the process of biodegradation of organic matter in anaerobic digestion resulting in higher yields in the production of biogas. This study aimed to evaluate the behavior of different inocula in anaerobic digestion of organic solid waste, determine the kinetic constant of formation of ammonia nitrogen and quantify the production of biogas. The experimental system was installed and monitored on the premises of EXTRABES from the UniversidadeEstadual da Paraíba, Campina Grande.Four different inocula were used in total: leachate, leachate adapted , UASB effluent , effluent of adapted UASB. All tests were done in triplicata. The leachate inocula and efluente of adapted UASB were pre - treated under anaerobic conditions for four months before starting the experiment and one of treatments was without the addition of inoculum for comparative study of treatments, resultind of 15 reactors monitored daily . The volumetric capacity of the reactor was 620 ml. Weekly, samples were collected of the solublefractions of the each treatment of liquid sample for analyzes of pH , total alkalinity , VFA , soluble COD , ammonia nitrogen and soluble orthophosphate. After 216 days of monitoring, the stabilized materialswere discarded and made the characterization by analysis of total COD , total phosphorus , fractions of solids and total nitrogen . The quantification of the volume of biogas performed was made daily using manometry system. Among the conditions studied, the treatment used leachate obtained total COD removal of 46.49 % , and showed higher pH contributing to better stability during treatment . T3 has removed 41 % of ammonia nitrogen and T1 removed of it. The removal of total solids was higher to T3 with 69.8 % of removal , followed by 45.7, 35.7, 23.1 and 22.5 % for T1, T2 , T5 and T4 , respectively. Biogas production was close to 23 L for all studiedtreatments . The kinetic constant of formation of ammonia nitrogen was higher for T1 indicating rapid degradation of organic matter in relation to other treatments studied.