Performance of semi-continuous anaerobic co-digestion of poultry manure with fruit and vegetable waste and analysis of digestate quality: A bench scale study

PATRICIA BRES; MARÍA EUGENIA BEILY; BRIAN JONATHAN YOUNG; JAVIER GASULLA; MARIANO BUTTI; DIANA CRESPO; ROBERTO J. CANDAL; DIMITRIOS KOMILIS

WASTE MANAGEMENT (ELMSFORD)

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2018 vol. 82 p. 276 - 284

0956-053X

Poultry manure (PM) can contain ammonium and ammonia nitrogen, which may inhibit the anaerobicprocess. The aim of this work was to evaluate the performance of anaerobic digestion of PM codigestedwith fruit and vegetable waste. Two semi-continuous bench scale (19L) stirred tank reactorswere used. The operating conditions were: 34.5 C, 2 gVS/L.d (organic load rate), 28 d of hydraulic retentiontime and 100 revolutions per m (1 h 3 times by day) for the agitation. The reactors were fed PMand a mixture of PM and fruit and vegetable waste (FVW) at equal proportions (based on wet weight).The performance of the anaerobic process was assessed through biogas and methane yields, reductionof organic matter, release of nitrogen compounds and the monitoring of stability indicators (pH, volatilefatty acids (VFA), total (TA) and partial (PA) alkalinity). Moreover, the digestate quality was evaluated todetermine potential risk and benefits from its application as biofertilizer. Toxicity was assessed usingDaphnia magna immobilization tests. Results showed that biogas and methane yields from PM-FVW were31% and 32% higher than PM alone, respectively. Values of organic matter, pH, alpha (PA/TA) and VFArevealed that stability was approached in PM and PM-FVW. The co-digestion of PM with FVW led tothe highest methane and biogas yields, lower FAN and TAN concentrations, and a better digestate qualitycompared to mono-digestion of this manure.