This study is to explore the anaerobic co-digestion (AcoD) of lignocellulosic and lipidic wastes, as two types of biomass (BM), with cattle manure (CM), using three inoculum-to-substrate ratios (ISRs; 0.5, 1, and 2) and three substrate composition ratios (SCRs; 20:80 [0.25], 50:50 [1], and 80:20 [4], viz. the lipid-to-lignocellulose ratios). The AcoD process was thus designed for 1-L, single-stage digesters in the batch mode, under mesophilic conditions (35 ◦C), based on 5 % total solids (TS) for the duration of 120 days. The highest efficiency of AcoD was then observed in treatments with ISR = 0.5 and SCR = 4, in which biogas (BG) production and methane (CH4) yield were respectively equal to 36 % and 45 % of the control sample, that is, the CM alone. In such conditions, BG production and CH4 yield were 0.128 and 0.117 m3/kg-VSadded, in that order, and volatile solids (VS) removal value was by 17 %. The key factors contributing to ineffective AcoD were failure to pass up acidic conditions, accumulated volatile fatty acids (VFAs), namely, the potential of hydrogen (pH) below 5 until the process completed, imbalance in ammonia (NH3) production and consumption all through this process, and possibility of extended long-chain fatty acids (LCFAs) in the reactors loaded with the mentioned substrates. The higher value of the final lipid, 31.5–140.7 %, in all treatments, as compared to that charged at the onset of the AcoD process, confirmed the poor conditions in the desired system. Besides, the kinetic modeling outcomes demonstrated that the logistic function (LF) model had higher compatibility with the experimental data, compared to the first order (FO) and cone function (CF) ones. The maximum BG production rate (Rm), 1.088 m3/kg-VS.d, additionally accounted for ISR = 0.5 and SCR = 4.

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