Možnosti zpracování kovových kalů pyrolýzní technologií

Abstract

This Ph.D. thesis provides evaluation of options of processing a comprehensively characterized metal sludge containing oil at pyrolysis conditions with the goal to determine the distribution and chemical composition of pyrolysis products. The performed chemical analysis shows potential use of metal sludge as secondary raw materials in the production of metals relative to the set of high content of iron in metallic form (up to 88.3 wt. %) and the presence of the alloying elements (Cr, W, Mo). For the set of high content of metalworking fluids (up to 45.4 wt. %) the metal sludge containing oil are evaluated as hazardous waste and after thermal treatment they are currently stored in hazardous waste incinerators as a landfill waste. For assess the thermal stability of oil contained in the metal sludge and the calculation of the kinetic parameters there was used the thermal analysis. In the assembled laboratory pyrolysis unit there was studied the influence of designed process conditions on the development of individual pyrolysis products. After applying a heating rate of 10 and 20 °C.min-1 to the final pyrolysis temperature of 450 °C, 550 °C, 650 °C with a holding time at a selected temperature for 30 min. there were quantitatively and qualitatively evaluated liquid, solid and gaseous products. Initial samples and solid pyrolysis products were analyzed by X-ray powder diffraction analysis method. For the pyrolytic solid residues the determination of carbidic and pyrolytic carbon was executed including analysis of kontent of C10 - C40. The analysis of the portion of original liquid samples obtained by sedimentation and pyrolysis liquid products was performed using an infrared spectrometer with Fourier transformation. In the pyrolysis gas depending on the temperature and heating rate there was chromatographically monitored levels of CO, CO2, H2, CH4, C3H8, C3H6, C2H6, C2H4. The contents of each of the 16 priority PAHs according to the U. S. EPA and their toxicological properties were determined at a heating rate of the sample IIIK 10 °C.min-1 to the final pyrolysis temperature of 450 °C, 550 °C and 650 °C with exposure time of 30 min.