1- Waste management strategies: the state of the art
2- Waste and wastewater management strategies: life cycle assessment (LCA) approach
3- Biogas production: pretreatment techniques
4- Biogas production: microbiological aspects
5- Feedstocks for biogas production: biogas and electricity generation potentials
6- Biogas production systems
7- Prominent parameters in biogas production systems
8- Biogas production systems: start-up process
9- Biogas production systems: operation, process control, and troubleshooting
10- Analytical methods in biogas production
11- Biogas purification and upgrading technologies
12- Applications of biogas and related products
13- Biogas plants: design and fabrication
14- Biogas plants: bio-refinery approach
15- Techno-economical aspects of biogas plants
16- Exergetic aspects of biogas production
17- Advanced modeling techniques in biogas production
18- Current state and future prospects of biogas industry in the world.