Hydrothermal treatment and gasifivation of olive mill wastewater using platin catalyst in supercritical water

Nowadays, curiosity on new and renewable energy sources increases continually. Biomass energy in these sources falls into priority. At the same time, various energy conversion technologies are applied and tried to produce energy from biomass. Catalytic hydrothermal gasification in supercritical water is an effective method that all manner of aquous organic mixtures are treated and gasified at temperatures and pressures over the critical point of water (T=374°C, P=221 bar). In these conditions, organics, which has nonpolar properties, are miscible completely with water, and a single phase is observed. In addition, the hydrogen bondings between water molecules dissociate because of high kinetic energy of them, and dielectric constant of water in supercritical conditions comes close to those of nonpolar organic solvents. The reactions can be carried out easily without mass transfer limitations. The molecules have high kinetic energy due to medium of supercritical water, and they come into collusion effectively because of density of the medium. Thus, it was obtained treatment efficiency upto 100 % in very short residence times by cataliytic hydrothermal gasification in supercritical conditions of water.In this study, the treatment and gasification of olive mill wastewater was investigated using a Pt/Al2O3 catalayst in a packet bad reactor at supercritical water conditions. The treatment and elimination of the olive mill wastewater is accepted as an important environmental problem which has to be solved in mediterian countries. High amount of organic contaminant in the olive mill wastewater are considered as a biomass source, and while its gasification is carried out in supercritical water, its treatment is provided at the same time.As a result of this work, gases such as hydrogen, methane, ethane, propane, propylene which can be used as energy, were obtained. With developed process, either organic content has been removed from wastewater and obtained energy from a real biomass. In accordance with this purpose, the experiments were carried out at a constant pressure of 250 bar, different five reaction temperatures (400, 450, 500, 550 and 600?C) and different five reaction times (10, 15, 20, 25 and 30 s). Effects of experimental conditions on gas composition, net gas flow rate, total energy amount and total organic carbon (TOC) exchange were investigated. Afterwards, experiments were made at 100, 150, 200, 250 bar pressure in order to examine effective of system pressure. The effects of reactant concentration on the same parameters were investigated at 2000, 4000, 8000, 10000 mg/L concentrations. Furthermore, using experimental data obtained, a kinetic model of catalytic decomposition reaction was developed.