Experimental study and techno-economic analysis of co-processing system for treatment of food waste with various impurities

•Experiments on separated FW solid and liquid fraction via AD and Py was conducted.•The impacts of FW fractions and impurities on methane yield was investigated.•Separating liquid from FW leads to reduced nitrogen-containing compounds in bio-oil.•ADCo-Py showed higher NPV and a more favorable IRR than ADCo-INC and PY.•Py and ADCo-Py needed 3.8 and 2.8 times more energy than ADCo-INC. The study assessed a co-processing system segregating food waste (FW) with different impurities into liquid (slurry) and solid fractions and treated using anaerobic digestion (AD) and pyrolysis (Py), respectively, which is defined as ADCo-Py. Biomethane potential tests showed higher methane yield from the FW slurry fraction (572.88 mL/gVSFW) compared to the whole FW (294.37 mL/gVSFW). Pyrolyzing the FW solid fraction reduced nitrogen compounds in bio-oil by 62 % compared to the whole FW. The energy balance and economic feasibility of ADCo-Py were compared with stand-alone AD, Py, and AD integrated with incineration (ADCo-INC). While all systems required extra energy, stand-alone Py and ADCo-INC needed 3.8 and 2.8 times more energy than ADCo-Py, respectively. Techno-economic analysis favored ADCo-Py, with a net present value (NPV) of $15 million and an internal rate of return (IRR) of 34 %. These findings highlighted FW separation as a promising approach, aligning with energy and economic goals in sustainable FW management.