Treatment of industrial wastewaters by utilizing in energy (CH4/H2) production via hydrothermal gasification

Within the scope of the thesis, it has been investigated how much the chemical oxygen demand and the pollutants in Opium Alkaloids Plant wastewater, which is resistant to treatment can be removed by the Hydrothermal Gasification (HTG) method. This wastewater with high organic carbon content is treated to a significant extent by HTG, while a gaseous product rich in H2 and CH4 is also produced which can be utilized as clean energy sources. Gasification experiments were carried out at the reaction temperatures of 300, 400, 500 and 600°C and at the pressure levels of 200, 275, 350 and 425 bar (500 and 600°C) with the wastewater supplied from the factory to determine the most appropriate reaction conditions. The most favorable amount of catalyst was determined by adding different amounts of K2CO3. The effect of catalyst type was examined with activated red mud catalysts synthesized in the laboratory, NaOH, KOH, Na2CO3, Raney Nickel 4200, Raney Nickel 2800, Activated Nickel, Nickel-Silica/Aluminum. The increase in reaction temperature increased H2 and CH4 yields and gasification efficiency (CGE). Higher pressures decreased the yields of H2 and CGE, and slightly increased the formation of CH4. Catalyst use increases gasification and causes changes in gas product composition and yield. Keywords: Biomass, wastewater, supercritical gasification, hydrogen, methane.