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The organic wastes generated from centralized wholesale markets from urban centres are predominantly disposed in dumpsites/landfills. Although anaerobic digestion (AD) of wastes is a promising option for producing bio-fuel, the key barrier is the limitation in the waste conversion efficiency that demands the need for the organic waste pretreatment. Hence, the extrusion pre-treatment of wastes prior to AD of slaughterhouse wastes (ESHW) with mixed vegetable, fruit and flower market wastes (EVMW), from a centralized-wholesale market in an urban area, was studied in batch and continuous AD processes. Batch experiments were carried out in mono- and co-digestion modes of extruded wastes. The results of the batch study revealed maximum specific methane yield of 354.9 mLN/g oDM during anaerobic co-digestion of extruded slaughterhouse wastes with mixed vegetable, fruit and flower market wastes in 1:3 proportion (ESHW/EVMW). Based on these results, lab-scale continuous reactor study (15 L) at varying organic loading rates (OLR) was carried out and the maximum biogas yield of 618.5 mLN/g oDM with a methane content of 62.6% and energy potential of 12.2 MJ/kg DM was obtained for extruded wastes at an OLR of 2.5 g oDM/L/d (E) when compared with non-extruded wastes that showed biogas potential of 503.7 mLN/g oDM (with energy potential of 10.2 MJ/kg DM). The outcome of the study revealed that extrusion pretreatment along with anaerobic co-digestion resulted in an increase in the biogas production therein showing enhancement in green energy production during anaerobic co-treatment of centralized wholesale market and slaughterhouse wastes in urban centres.