What is Methanogenesis and Biomethanation?
Simply put, Methanogenesis or Biomethanation is the process of combining organic waste materials into biogas and manure. This is done through the use of microorganisms under anaerobic that decompose such biodegradable wastes in the absence of oxygen.
Biomethanation provides an excellent urban waste management solution as it results in several end products that can be used for a wide range of applications. Some of the major advantages of using Biomethanation for managing urban waste products are mentioned below.
Generation of biogas, the prime advantage of using this method. Biogas is a gaseous fuel that can be easily used for energy generation and production of heat.
Biomethanation plants do not require significant investments and can be deployed on small scales. Unlike other kinds of waste treatment processes, this process is completely self-sufficient and doesn’t require an external power source.The system is completely sealed and enclosed and collects every bit of the gas for utilization. This includes a whole host of harmful greenhouse gases.
Biomethanation results in the elimination of foul odor, stopping the growth of rodents and pests and any kind of visible pollution or social issues due to garbage. The waste product that is left behind after the production of biogas is an excellent form of manure and can be used to treat soil. The construction of such Biomethanation plants is completely modular and they need very less area for construction.
The process of Biomethanation
There are three basic groups of microorganisms that are used in for Methanogenesis or Biomethanation, fermenting bacteria, organic acid oxidizing bacteria, and methanogenic archaea. These various microorganisms continuously decompose organic matter and break it down into methane and carbon dioxide. There is a syntrophic relationship between the hydrogen-producing agents (known as antogens) and the hydrogen scavengers or consumers (homoactogens, hydrogenotrophic methanogens, and others) which is vital for the production of bio-methane.
One of the most important steps in the process is determining the practical and theoretical values of methane generation and thereby get an estimate of the methane potential of the region and the plant. This plays a critical role in optimization of processes, resources and in simplifying plant design and configuration. Conducting such an analysis will also result in the economic viability of the plan.
There is a wide range of applications that have been developed for the end products of Biomethanation. Different types of Biomethane plants use different kinds of reactors. Some of the various kinds of reactors that are used are fully mixed, plug-flow and biofilm among others. The end process parameters such as retention time, loading rates and temperatures are altered and tweaked in order to maximize the energy generation, decrease retention time and improve the stability of the entire process.
The implementation of Biomethanation might be a challenging task, especially in developing countries where this process can have the maximum advantage. This is primarily because waste to energy reactors and equipment need to be imported to those countries which often entail quite high capital investments.