The paper presents the results of studies on ashes produced from burning wood biomass in closed wood-fired furnaces, in individual household furnaces (Silesian Province, Poland). Dry sieve analysis and detailed granulometric analysis were performed with the Analysette 22 Micro Tec plus analyser. Content of the basic elements (Al, Si, P, Na, K, Mg, Ca, Fe) and potentially toxic elements (As, Pb, Cd, Zn, Cu, Ni, Cr, Hg) was determined by atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Relative enrichment factors (REF_s) were calculated for the elements (Pb, Cd, Zn, Cu, Ni, As, Hg, and Cr), and the emissions (E) of Pb, Cd, Hg, and As to the environment were estimated. The carbon content (40.2%–45.8%), H (3.7%–6.1%), O (46.2%–50.2%), N (0.12%–0.32%), and S (0.11%–0.96%) in wood biomass varies and depends on the wood species and drying period. The content of volatile parts in wood biomass ranges between 69.3 and 81%. Ash content varies between 2.6 and 18.3%. The wood calorific value ranges from 13.6 MJ/kg to 17.4 MJ/kg. Moisture content in the wood biomass ranges from 13.7% (briquette) to 46.7% (fresh birch). Identification of mineral composition and phases yields a high share of calcite, monetite, fairchildite, and quartz in the examined ashes. The combustion of wood biomass in fireplaces results in increased emissions of Pb and Cd to the atmosphere and may be the cause of introducing pollutants to waters and soils during ash storage.

This study aims at detailed characteristics and comparison between dusts from various iron and non-ferrous metal production processes in order to identify individual mineral phases, chemical composition, and their influence on the values of magnetic susceptibility. Various analytical methods used include inductively coupled plasma optical emission spectroscopy, X-ray diffraction, scanning electron microscopy, and Mössbauer spectroscopy integrated with magnetic susceptibility measurements and thermomagnetic analysis. Metallurgical wastes that have arisen at different production stages of iron and non-ferrous steel are subjected to investigation. The analyzed dust samples from the iron and non-ferrous metallurgy differ in terms of magnetic susceptibility as well as their mineral and chemical composition. The research confirmed the presence of many very different mineral phases. In particular, interesting phases have been observed in non-ferrous dust, for example challacolloite, which was found for the first time in the dusts of non-ferrous metallurgy. Other characteristic minerals found in non-ferrous metallurgy dusts are zincite, anglesite, and lanarkite, while dusts of iron metallurgy contain mostly metallic iron and iron-bearing minerals (magnetite, hematite, franklinite, jacobsite, and wüstite), but also significant amounts of zincite and calcite.

The study aimed at conducting a detailed analysis of apple pomace (AP), walnut shells (WS), and sunflower husks (SH) ashes as potential raw materials for combustion at a temperature of 400 ± 15 °C (individual home furnace). Research methods such as ICP-OES/MS (atomic emission spectrometry with excitation in induced plasma and mass spectrometry), XRD (X-ray diffraction), and SEM–EDS (scanning electron microscopy with quantitative X-ray microanalysis) were utilized. Elemental CHNSO FlashSmart series analyser (Thermo Scientific) was employed for the analysis of oxygen (O). An automatic IR analyser was used to determine the carbon (C), total sulphur (S), and hydrogen (H) content. Total sulphur (S) and chlorine (Cl) were measured by the PN-EN ISO 16994:2016 standard. The nitrogen (N) content was determined by the catharometric method of chlorine by ion chromatography (IC). Higher concentrations of potentially toxic elements (PTE) such as As, Cr, Zn, Cd, Cu, Ni, Pb, Tl, U, and Th were detected in apple pomace ashes. The mineral composition of biomass ashes was found to be highly diverse, with sunflower husk ashes containing the highest amount of minerals, including quartz, dolomite, calcite, magnesite, sylvite, arcanite, fairchildite, and archerite. Quartz was identified in apple pomace ash, while in sunflower husk ash, it was determined to be present only as an amorphous substance. The estimated total dust emission to the atmosphere from biomass combustion was found to be at a similar value (1.23 to 1.35 kg/Mg).

Presented are the results of the examination of the chemical and mineral composition as well as iron compounds in furnace hearth slags coming into existence after the burning of hard coal. The samples of furnace hearth slags from heat and power plant and the hearths of the individual home furnaces fitted out with grate firings were compared. The examination methods like X-ray diffraction (XRD) with powder method, Mössbauer spectroscopy, scanning electron microscopy and ICP analysis were used. The main components of furnace hearth slags are SiO₂, Al₂O₃ and Fe₂O₃. On the basis of the X-ray diffraction, it was found that the domination components of furnace hearth slags are mullite and quartz. Furnace hearth slags are different as for the content of the concentration of toxic elements (Cd, Cr, Ni, Tl, Pb, Zn, As, Ba and Cu) and Fe.