Marek Kucbel

Temporal and seasonal variations of black carbon in a highly polluted European city: Apportionment of potential sources and the effect of meteorological conditions

Black carbon - a primary component of particulate matter emitted from an incomplete combustion of fossil fuels, biomass, and biofuels - has been found to have a detrimental effect on human health and the environment. Since black carbon emissions data are not readily available, no measures are implemented to reduce black carbon emissions. The temporal and seasonal variations of black carbon concentrations were evaluated during 2012-2014. The data were collected in the highly polluted European city - Ostrava, Czech Republic, surrounded by major highways and large industries. Significantly higher black carbon concentrations were obtained in Ostrava, relative to other European cities and the magnitude was equivalent to the magnitude of black carbon concentrations measured in Poland and China. The data were categorized to heating and non-heating seasons based on the periodic pattern of daily and monthly average concentrations of black carbon. A higher black carbon concentration was obtained during heating season than non-heating season and was primarily associated with an increase in residential coal burning and meteorological parameters. The concentration of black carbon was found to be negatively correlated with temperature and wind speed, and positively correlated with the relative humidity. Other black carbon sources potentially included emissions from vehicle exhaust and the local steel-producing industry.

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.

Comparison of enrichment factors for heavy metals in urban street dust and air aerosols

The article deals with the possibility of comparison of enrichment factors in air aerosols (PM10) and in the street dust, which is influenced by air pollution. For Pb and Sb, the same value of enrichment factor for both matrices was determined. The highest enrichment index (> 100) in air aerosols was found for Cd, Sb, and As, and also for Pb, and Zn (approximately 100). Enrichment factor shows significant differences in the summer and winter period, for Cd, Sb, As, Pb, and Zn it is > 2x higher in winter. Enrichment factor in street dust was also evaluated using geochemical background of soils from Olomouc. It was found that the highest value of enrichment factor is achieved by Cu, which comes from transport (probably bus operation).

Possibilities of the utilization of char from the pyrolysis of tetrapak

Since the cellulose used in the production of tetrapak is of very high quality, the char generated during pyrolysis should be influenced mainly by the pyrolysis temperature. This article aims to determine the chemical composition of biochar prepared at the temperatures of 400, 500, 600 and 700 °C and its environmental properties determined by the presence of organic compounds with toxicity and relatively high mobility in the environment. The analytical pyrolysis of char was used to identify the following groups of organic compounds: alkanes, cycloalkanes, alkenes, cycloalkenes, alkynes, alkadiens, ethers, alcohols, nitrogen compounds, nitrils, ketones and aldehydes, compounds containing phenols, furans, benzofurans, PAHs (polycyclic aromatic hydrocarbons), carboxylic acids, compounds containing benzenes and markers indicative of the presence of synthetic polymers (polyethylene layers, a part of dyes, antioxidants, stabilizers), and fragments of cellulose. Concerning the use of char as a soil conditioner, its ecotoxicity was monitored (Folsomia candida) by monitoring its addition to the artificial soil (char addition: 0.5, 1, 2.5, 5, 10, 15, 20, 50 and 100%). The lowest reproduction inhibition of Folsomia candida is caused by biochar prepared at the temperature of 400 °C and 700 °C, but it is not suitable for the agricultural application, the concentration of PAHs is three times higher than the EBC limit. Low-density polyethylene which is present in the aseptic box in concentration of 6%, can degrade biochar so that it cannot be used as a soil amendment. The results of the char analyses show that the pyrolysis temperature is a decisive factor in the applicability of biochar.

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.