Evaluation of the Design and Operating Conditions of an Adsorption Reactor for Hydrogen Sulfide Removal in Biogas

Abstract

Purpose This study aims to provide basic data for the design and operation of adsorption towers to effectively remove hydrogen sulfide (H2S) from biogas. Methods Various adsorbents, such as activated carbon, zeolite, and iron sulfate-treated zeolite (Zeolite-Fe7), were used to evaluate the efficiency of H2S removal. The experiments were conducted under different operating conditions, including reactor length, gas flow rate, humidity, and the combined application of absorption and adsorption methods. Key factors influencing the performance of each adsorbent and hydrogen sulfide removal were analyzed. Results and Discussion Activated carbon recorded the highest H2S removal efficiency at approximately 97.8%, while zeolite and Zeolite-Fe7 showed relatively lower efficiency. The gas flow rate significantly impacted the removal performance of the adsorbents, and reactor length and humidity had varying effects depending on the adsorbent. Additionally, when absorption and adsorption methods were applied simultaneously, a removal rate of about 95.6% was achieved. Conclusion Activated carbon demonstrated higher efficiency and resistance to humidity compared to other adsorbents, making it the most suitable material for H2S removal from biogas. This study provides basic data for optimizing the design and operation conditions of adsorption towers and is expected to contribute to the future design of pre-treatment processes for H2S removal in biogas.

Keywords

• carbon neutrality
• biogas upgrade
• hydrogen sulfide
• adsorption