###### Abstract  
Anaerobic digestion (AD), the oldest technology used for treating waste, converts organic matter into biogas in the absence of oxygen. The current efforts focuses on improving the digestion of a local industrial wastewater to produce biogas and treat water for reuse. A lab-scale up-flow anaerobic sludge blanket (UASB) reactor operated at 37 \({}^{\circ}\)C was employed for the biodegradation the industrial wastewater. A one-factor-at-a-time (OFAT) approach was used to study the effects of influent chemical oxygen demand (CODin), hydraulic retention time (HRT), and magnetic nanoparticles (magnetic) on UASB biogas and COD elimination from digestate wastewater. The optimum HRT for the biodegradation of municipal wastewater was found to be 21 days with contaminants' removals of 94%, 90.1%, and 98.9% for COD, color, and turbidity, respectively. The addition of magnetite resulted in 225 mL of cumulative biogas produced with 73% methane content, and treatability efficiency of 85%. The most influential factor was magnetite load, which stimulated the microbial activity via redox catalytic reaction in degrading the high organic wastewater (9590 mg COD/L) into biogas production. The prospects of upgrading lab-scale of this technological concept for bioenergy production is viable to mitigate wastewater management and fossil fuel environmental challenges. a pacs: 12.38.-b, 11.38. Following the development of the energy crisis, anaerobic digestion technology has advanced at a rapid pace. Even though AD offers many advantages, it faces significant problems that prevent it from being applied in a variety of industries. Low biogas yield has been reported to be caused by a lack of process control and optimization [5]. One of the major technological problems is the formation of toxic intermediate composites, including volatile fatty acids (VFA), due to the presence of acidogenic microorganisms, and the concentration of toxic metals in wastewater [6]. Other difficulties include high financial costs (operation and transportation), insufficient buffer capacity, and process instability [7; 8]. These are caused by a pH reduction during the first stage of digestion and the inhibition by ammonia, long-chain fatty acids, and hydrogen sulfide. This proves that anaerobic digestion is very sensitive to toxicants and their presence can inhibit the process and result in process failures [9; 10]. Another significant challenge is the lack of appropriate reactor design, where reactor design is still usually created by the rules of thumb. Overall, wastewater characterization, biodegradability, bacterial activity development, accessibility, CH\({}_{4}\) production enhancement, and nutritional balance are regarded as major hurdles to the effective generation of biogas [11]. During digestion using the UASB system, agitation typically improves system performance by providing greater interaction between substrates and microorganisms while reducing the production of scum, which can inhibit gas movement through the surface. By adopting excellent agitation in the anaerobic digester, such as localized build-up of heat, intermediates such as acids and bases from the pH regulating system might also be avoided. Mechanical mixing, biogas recirculation, or slurry recirculation can all be used. Investigations examining the influence of mixing on the overall efficiency of anaerobic digesesters suggest that mixing by slurry recirculation outperforms mechanical impeller and biogas recirculation with an increase in COD removals [12; 13]. When added into an AD system, all three types of mixing greatly enhance treatment efficiency when compared to unmixed digesters. Furthermore, slow mixing rates have been demonstrated to result in increased methanogenic activities in the operation of anaerobic bioreactors [14]. Anerobic digestion efficiency may be increased by either appropriately changing the existing digester design or adopting appropriate advanced operating procedures.