Search

Biogas production offers numerous advantages, but ongoing research and development are essential to enhance efficiency, accelerate production, and ensure cost-effectiveness as a sustainable energy source. This comprehensive review examines the anaerobic digestion process of cow dung, analyzing critical factors such as reactor type, operating conditions, and feedstock pretreatment. By breaking down complex organic structures, pretreatment methods such as thermal and chemical treatments significantly increase biogas yields. Additionally, the use of additives, such as trace metal nanoparticles, can enhance methane production, making the anaerobic digestion process more efficient. Also, innovative applications for biogas facilities are discussed, including integrating biogas production with hydroponic farming, which repurposes nutrient-rich byproducts for crop growth, and using waste heat to generate electricity. Furthermore, steam methane reforming offers a pathway for hydrogen production, which increases biogas plants’ versatility. The findings of this study provide actionable strategies to optimize biogas production and utilize biogas facilities to promote sustainability and reduce reliance on fossil fuels. According to this study, taking advantage of these novel approaches will maximize the benefits of biogas and contribute to the transition toward a greener economy.The anaerobic digestion process of cow dung to yield biogas is reviewed, analyzing critical factors such as reactor type, operating conditions, and feedstock pretreatment. Innovative applications for biogas facilities are discussed, including integrating biogas production with hydroponic farming and using waste heat to generate electricity.Graphical Abstract

The design, manufacture and experiment of a shaft power unit for converting a micro-turbojet engine to a micro-turboprop in the class of less than 20 kW with the aim of obtaining maximum shaft power were described in this study. For this purpose, a Wren100 micro-turbojet engine was used as the gas generator, and the specifications of its outflow were measured. The optimal configuration of the inter-stage diffuser, which was an annular S-type diffuser, was selected based on its small total pressure drop and outlet flow uniformity. The power turbine was a single stage axial turbine that was designed based on the fixed nozzle angle assumption without any taper or twist in its stator. The turbine rotor was a bladed disk (Blisk) in which its unique blade profiles were designed based on the Wilson method. Subsequently, the shaft power unit was completed by designing and manufacturing an exhaust complex and gearbox. Finally, the micro-turboprop engine was tested with an overloading propeller. The results show a significant increase in the extracted power, an acceptable efficiency of the power turbine, and a significant reduction in the Specific Fuel Consumption (SFC) compared to other engines that use similar gas generators.