Power to Gas Pilot Plant for CO2 Methanation with a Ni-Based Catalyst

In the context of power to gas (PtG) technology, different studies are developed to convert carbon dioxide and hydrogen into methane (synthetic natural gas, SNG). The aim of this technology consists of storing renewable energy and reducing greenhouse gas emissions with a net zero process. The present study focuses on the analysis of a small pilot plant designed for the methanation of CO2 to produce synthetic methane. The size of this plant is set to produce 1 Nm3/h of synthetic methane by using a monotube plug flow reactor (PFR) filled with a Ni-based catalyst, which allows the CO2 methanation to occur according to the Sabatier reaction. The study analyzes various process parameters over a 10 h period to assess the system's dynamic behavior, including CO2 conversion and CH4 content. The experimental setup features enhanced temperature control through a diathermic oil circuit and optimized reactor design, ensuring stability and reducing hot spot risks. This configuration minimizes pressure drops, leading to an efficient performance. During the process, CO2 conversion of approximately 70% and CH4 composition of 63.4 vol % are reached. Overall, the system effectively handles fluctuations in renewable energy supply and demonstrates operability under constant reactants flowrates.