Chemometric analysis of air pollutants in raw and thermally treated coals - Low-emission fuel for domestic applications, with a reduced negative impact on air quality.

The emission of pollutants into the air during the combustion of solid fuels in households is still a significant problem in many European Union countries, including Poland. These emissions are a significant source of many air pollutants formed during incomplete combustion and has been identified as one of the leading environmental risk factors for these populations. One of the solutions is to utilise thermally processed solid fuels. This article discusses the concentrations of pollutants emitted as a result of the combustion of conventional fuels and new low-emission fuel in out-of-class heaters. To gain better insight into the relationships between fuel type and flue gas quality, chemometric methods and variance analysis were used. Principal component analysis confirmed that the fuel type significantly influences the level of dust emissions and the total organic carbon and sum of polycyclic aromatic hydrocarbons in the dust. Clustering analysis identified how the concentrations of polycyclic aromatic hydrocarbons correlate with the amounts of dust and total organic carbon and showed that this correlation is proportional to the size of the molecule and consequently the number of aromatic rings. The use of low-emission fuel as a solid fuel in households, as our analyses have shown, can reduce the concentrations of dust, total organic carbon and polycyclic aromatic hydrocarbons by up to 50 times, thereby reducing air pollutants in cities.

Characterization of Graphite Oxide and Reduced Graphene Oxide Obtained from Different Graphite Precursors and Oxidized by Different Methods Using Raman Spectroscopy.

In this paper, the influences of the graphite precursor and the oxidation method on the resulting reduced graphene oxide (especially its composition and morphology) are shown. Three types of graphite were used to prepare samples for analysis, and each of the precursors was oxidized by two different methods (all samples were reduced by the same method of thermal reduction). Each obtained graphite oxide and reduced graphene oxide was analysed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy (RS).

Preliminary studies on the treatment of wastewater from biomass gasification.

This paper presents completed research on the purification of undiluted raw water and organic condensates obtained in biomass thermal conversion processes such as gasification, which are rarely addressed in published studies. However, similar studies involving the characterization and purification of aqueous solutions obtained from process gas treatment after the gasification of biomass are available. Condensation of water-organic condensate from process gas helps to reduce the amount of water required by the purification process and the cost of the process technology and water consumption. Oil scrubbers can be used in this case instead of water scrubbers. In this case, the obtained condensate must be subjected to purification processes. This paper presents the results of our research, possible methods of treatment (chemical and biological methods), and the approximate cost of the reagents required for the purification of condensate for specific assumed degrees of purification. The best results from the chemical purification using the Fenton method were obtained with the ratio V(H2O2)/V(cond.) = 6.0 and the ratio V(H2O2)/Fe = 0.0375. To prevent precipitation of ferric hydroxide, this value can be reduced 20-fold, which reduces the total degree of purification to 90%. The cost of almost complete cleaning of tested condensates was calculated to be approximately 2000 USD per/m(3). This cost can be reduced by a factor of approximately four assuming 100% cleaning for 2-furaldehyde, furfuryl alcohol and phenol; acetaldehyde, propane-2-one (acetone), methanol and acetic acid are oxidized by 50%.