Konstantin Raclavsky

Correlation Between Magnetic Susceptibility and Heavy Metal Concentrations in Forest Soils of the Eastern Czech Republic

Magnetic susceptibility measurements were performed on 2,000 samples of forest soils from the Ostrava-Karvina industrial region (Czech part of Upper Silesian Coal Basin) and the Moravian-Silesian Beskydy Mountains and their piedmont area, Podbeskydi. Concentrations of selected elements were determined in 1,200 samples from the same set. Industrial facilities (metallurgical industry and power plants) located in this region represent major sources of both magnetic particles and risk elements contaminating soils within the industrial region and neighboring mountainous areas. The magnetic susceptibility has a closely correlated relationship with Zn, Fe, As, Pb and Cu concentrations in soils. The magnetic susceptibilities vary inversely with distance from the sources. The behavior of individual chemical elements during transport and deposition was studied by means of ratios of concentrations of elements and values of magnetic susceptibility. Metals correlating very closely with magnetic susceptibility (Fe and Zn) were deposited together with dust particles, whereas Pb, As, and trace amounts of Zn can create independent particles which are components of long distance transport and deposition. The concentrations of Pb, As and, in part, Zn in soils are strongly dependent on the elevation of the sampling site; in the uppermost parts of mountains they are enriched. Other studied elements show neither relationship with sources of air pollution, nor with the geomorphology of the area. Concentrations of chemical elements V, Cr, Rb, Sr, U, Zr, Ca, Bi, Mn and Ti are related mostly to underlying sedimentary rocks.

Utilization of carbon produced by torrefaction of grass for energy purposes and related risks

Nine species of perennial grasses were studied as a possible raw material for energy production. Torrefaction at 200 degrees Celsius was used for production of biochar. Values of H/C ratio in individual species were determined in order to estimate the degree of thermal transformation. The attention was paid to the influence of inorganic components on the slagging and fouling. The water leaching was tested as a mean for decreasing the content of alkalies. Mineral phases present in biochar were determined by X-ray diffraction. The torrefaction process appears to be suitable for preparation of relatively high-quality fuel from grass. The content of risk alkalies can be minimized by water leaching.

Possibilities thermal utilization of solid char from pyrolysis of municipal solid waste

Requirements for quality of solid char from pyrolysis of municipal solid waste were studied from the point of view of possible utilization for combustion. Laboratory tests of pyrolysis were carried out with samples of municipal solid waste with various moisture. Mineral phases in solid char were determined by X-ray diffraction. Behavior of hazardous elements during pyrolysis was studied and possibility to control selected risk elements by technical means was proposed.

Characterization of Organic Matter Released during Analytical Pyrolysis of PM10 Samples Obtained from Biomass and Oil Combustion

The composition and origin of organic matter (OM) released form three PM10 samples obtained from biomass and oil combustion was investigated in this study. The Py-GC/MS system was applied and experiments were conducted at 5 °C/min to 750 °C. A difference in the composition and therefore in OM between the examined samples was observed. The greatest variation in released compounds was noted for PM10 sample obtained from biomass combustion. Whereas the least variation in composition was observed for PM10 sample obtained from B oil sample. The latter consisted in majority of squalene (81.5 %). As a result, the quantity of OM released by the biomass sample was greater by 18.2 % and 33.9 % that the quantity released by A and B oil samples, respectively.

Parameters Influencing the Utilization of Composts for Energy Production

Ten composts produced by composting plants in the Moravosilesian Region (the Czech Republic) were studied from the point of view of their possible utilization for energy production. The parameters relevant for this possible application of low-quality composts were determined: elemental composition (C,H,O,N,S), volatile combustibles, fixed carbon, ash, gross calorific value, moisture, water leachable potassium and chlorine, alkali index, C/N.

Problems with utilisation of engineering wood for energy purposes

Waste engineering wood in the form of chipboard and plywood is a potential source of renewable energy in boilers for biomass combustion. The conditions causing the silicate melt slagging during combustion were studied by proximate analysis, mineralogical analysis using X-ray diffraction, scanning electron microscope with energy dispersive analyser and thermogravimetry. Slags are formed by refractory mineralogical phases of Ca, Si, Ti and Al.

The influence of pyrolysis temperature on the chemical composition and the energy properties of char from tetrapak

The chemical composition of char obtained from tetrapak cardboard was monitored in dependence on pyrolysis temperature ranging from 400 to 700 °C together with its influence on energy parameters (calorific value). The highest calorific value 27–28 MJ/kg was determined for char obtained at a temperature of 400 °C, which is caused by the highest content of hydrocarbons (alkanes and alkines) and the lowest content of undifferentiated organic matter. The highest homogeneity of chemical composition of char was found for the temperature of 600 °C.

The Composition of Humic Acids Separated from Compost Prepared from Biologically Degradable Waste

Humic substances (humic acids and fulvoacids) were studied in compost produced from biologically degradable waste. Pyrolytic gas chromatography with mass spectrometrical detection was used for determination of arenes (toluene, styrene, p-xylene, benzene and ethylbenzene) in the pyrolysate. An influence of composition of biologically degradable waste on humification process in composts can be evaluated from data on amount and ratios of humic acids and fulvoacids.