Production of biogas by SCF technology

Abstract

PRODUCTION OF BIOGAS BY SCF TECHNOLOGY Article Highlights • An overview of the state-of-the-art of hydrogen production technologies • An overview of recently published papers dealing with SCWG of model compounds • Summary of investigations on SCWG of agricultural and food processing wastes in recent 3 years • Technical requirements and fundamental studies to support gasification for hydrogen production Abstract Hydrogen is expected to become an important fuel in the long-term since in combination with fuel cells it offers the opportunity of an intrinsically clean energy supply. By application of supercritical water gasification (SCWG) concept, sustainable hydrogen can be produced from biomass and waste. This paper offers an overview of some recently published research dealing with SCWG of model compounds and a summary of the investigations on SCWG of real agricultural and food processing wastes. In the frame of our work, intense research was performed to support analyses of SCWG of glycerol and was supported by the investigation of phase equilibrium for the systems gas/water and gas mixtures/water. When glycerol/water solutions were directly injected in the reactor operating at supercritical conditions, gases with high C2+ were obtained by the reforming in supercritical water unit. To reduce the hydrocarbon concentrations and to obtain a syngas with higher CO/CO 2 ratios from a mixture of gases (H 2 , CO, CO 2 and CH 4), catalytic reactions at high pressure and temperature were introduced reflecting in an increase of the content of H 2 and CO. Solubility measurements were conducted for the binary systems of gas and water at elevated pressures and temperatures.