Aristotelis Triantafillidis

This study investigates the potential of selected plant species for environmental restoration and phytostabilisation in lignite mine waste dumps in Western Macedonia, Greece. Field sampling was conducted in three representative sites, where both soil and plant tissues were collected and analysed using X-ray Fluorescence (XRF). A total of six species (Pinus spp., Acacia spp., Populus spp., Cupressus spp., Cuprocyparis leylandii, and Tamarix spp.) were evaluated for their ability to grow in low-fertility substrates and their capacity to accumulate potentially toxic elements (PTEs). The findings indicate that soil chemistry is primarily influenced by geogenic factors, with elevated concentrations of Ca, Si, Mg, and K, consistent with the carbonate-rich geology of the Ptolemaida basin. Concentrations of PTE (Ni, Cr, Zn, Pb) remain below established toxicity thresholds, and Hg levels are negligible (<0.03 mg/kg). Plant tissue analysis revealed selective nutrient uptake and limited translocation of PTEs to aerial parts. Although the studied species do not exhibit hyperaccumulator characteristics necessary for phytomining, they exhibit strong phytostabilisation capacity, supporting erosion control and ecological restoration without increasing environmental risk.

This work offers a comprehensive examination of ICP-MS as a higher-level analytical method compared to atomic absorption spectrometry (AAS) and X-ray fluorescence (XRF). Comparisons between the ICP-MS average mean difference and AAS were made with the determination of the concentration of trace elements in the same solid alternative fuel samples, while comparisons between ICP-MS and XRF were made by the determination of the concentration of major elements in the same solid alternative fuel samples, resulting in the superiority of the method. The results of the relative mean differences (RDMs) between ICP-MS (7.56%) and XRF (9.42%) regarding the concentration of major elements compared with the reference values in solid biofuel samples, while the RDMs for the solid recovered fuel samples were 8.9% for ICP-MS and 12.27% for XRF. The same procedure was followed for the determination of the concentration of trace elements with ICP-MS and AAS, thus obtaining the results for solid biofuel samples (average %RMD_ICP-MS = 12.77 and RMD_AAS = 13.9) and SRF samples (average %RMD_ICP-MS = 10.02 and RDM_AAS = 11.10) in relation to the reference values. While acknowledging that the initial cost and complexity of operation may deter some from adopting ICP-MS, the study asserts that the advantages of enhanced precision, sensitivity and speed of analysis validate the investment. Hence, ICP-MS is an extremely important laboratory tool used in modern physics and chemistry and has a wide range of applications: biological materials, high purity reagents and metals, atomic nuclear materials, geological samples and food.

The mercury content is among the parameters that characterise the quality of Solid Recovered Fuels (SRFs), which constitute alternative solid fuels of increasing interest. In this study, a direct mercury analyser was utilised in the analyses of SRF samples originating from Automotive Shredded Residues (ASRs). Two SRFs and one liquid reference material were measured to test the accuracy and sensitivity of the instrument. The mean values of the two SRFs and one liquid reference material (RM) were 0.171, 0.324 mg/kg, and 0.141 mg/L. These values were compared with the reference ones as follows: 0.168, 0.382 mg/kg, and 0.137 mg/L. Mercury content was detected in the analysis samples of four different particle sizes (8 mm, 2 mm, 1 mm, 0.5 mm, and 0.25 mm) for each SRF sample in order to demonstrate the direct mercury analyser operation and to compare it as an alternative to mercury determination via atomic absorption spectrometry. The measurements showed that grinding down to 1 mm was sufficient for most SRF cases while grinding down to 2 mm might be enough for a few cases. As an overall conclusion, the direct mercury analyser can be regarded as an efficient laboratory tool, offering a robust alternative to the atomic absorption spectrometry procedure, especially in terms of accuracy, speed, safety, and cost-effectiveness.

This study presents an overview of the role that clean energy technologies can play in the decarbonisation path of Greece’s most carbon-intensive region, namely Western Macedonia. The region has been requested to adjust its production model to the new requirements of the Green Deal Initiative, while simultaneously proceeding to restructure its productive model towards a full phase-out of coal activities. The survey presented below will summarise the main findings and estimates of the clean energy potential from a technical and research point of view, and furthermore present assessments on the potential impact this could have on job creation and regional economic development in terms of potential investments. This study’s goals are to identify and promote actions to accelerate innovation performance in the clean energy domain and, simultaneously, serve as a co-working space among key stakeholders from business, government, civil society and innovation who share a vision for a sustainable future. Finally, this study highlights the importance of accelerating innovation in the clean energy domain—spanning energy production, distribution and consumption.