Solid-Recovered Fuel to Liquid Conversion Using Fixed Bed Gasification Technology and a Fischer–Tropsch Synthesis Unit – Case Study

In order to utilise energy-rich solid waste, its liquid conversion into valuable hydrocarbon (HC) chains is one of the ways followed worldwide to decrease the oil processing and waste landfilling at the same time. The unique fixed bed updraft gasification reactor with an oscillating circular grate, situated in VŠB – Technical University of Ostrava, Czech Republic, can generate up to 90 m3·h−1 of CO and H2-rich synthetic gas. Such valuable mixture is suitable for the gas to liquid conversion in Fischer–Tropsch Micro Catalyst Bed (F-T MCB) unit, where more complex substances of higher temperature and pressure form in the environment. This article focuses on solid-recovered fuel (SRF) gained as a mixture of industrial and communal waste sources. Gasification of such material in the fixed bed reactor can produce approximately 600 and 250 m3 of CO and H2, respectively, per ton of SRF in the abided gasification conditions. The gas, retrieved from the process, undergoes a thermochemical reaction on the surface of a catalyst within the reactor of the Fischer–Tropsch unit. As a result, a highly valued HC liquid is achieved from the suitable, non-recyclable waste treatment. Cobalt and iron catalysts in their plain form, as well as the catalysts enriched with Mn/K enhancers are put in comparison in this study. The quality and quantity of the synthesis product are examined and the technological aspects of both units are described. The amount of HC synthesis product ranges from 18 to 45 kg per ton of fuel. The composition tends to form HC chains in favour of groups of alcohols and alkanes.This work was prepared within the projects ‘Innovation for Efficiency and Environment –Growth’, identification code LO1403, with financial support from the Ministry of Education, Youth and Sports (MEYS) in the framework of the National Sustainability Programme, and ‘Maximazing Efficiency of Energogas Cleaning’, identification code SP2020/113. Also, the publication has been prepared using the results achieved with the infrastructure in open-access mode within the project ‘Efficient Use of Energy Resources Using Catalytic Processes’, identification code LM2015039, which has been financially supported by the MEYS of the Czech Republic within the targeted support of large infrastructures. The project has been integrated into the National Sustainability Programme I of MEYS through the project Development of the UniCRE Centre (LO1606)

Valuable Secondary Habitats or Hazardous Ecological Traps? Environmental Risk Assessment of Minor and Trace Elements in Fly Ash Deposits across the Czech Republic

Deposits of coal combustion wastes, especially fly ash, are sources of environmental and health risks in industrial regions. Recently, fly ash deposits have been reported as habitat surrogates for some threatened arthropods in Central Europe. However, the potential environmental risks of fly ash have not yet been assessed in the region. We analysed concentrations of 19 minor and trace elements in 19 lignite combustion waste deposits in the Czech Republic. We assessed their environmental risks by comparison with the national and EU legislation limits, and with several commonly used indices. Over 50% of the samples exceeded the Czech national limits for As, Cu, V, or Zn, whilst only V exceeded the EU limits. For some studied elements, the high-risk indices were detected in several localities. Nevertheless, the measured water characteristics, the long-term presence of fly ash, previous leaching by acid rains, and the low amount of organic matter altogether can infer low biological availability of these elements. We presume the revealed high concentrations of some heavy metals at some studied sites can be harmful for some colonising species. Nevertheless, more ecotoxicological research on particular species is needed for final decision on their conservation potential for terrestrial and freshwater biota.info:eu-repo/semantics/publishedVersio

Bioaccumulation of chemical elements at post-industrial freshwater sites varies predictably between habitats, elements and taxa: A power law approach

Elevated environmental levels of elements originating from anthropogenic activities threaten natural communities and public health, as these elements can persist and bioaccumulate in the environment. However, their environmental risks and bioaccumulation patterns are often habitat-, species- and element-specific. We studied the bioaccumulation patterns of 11 elements in seven freshwater taxa in post-mining habitats in the Czech Republic, ranging from less polluted mining ponds to highly polluted fly ash lagoons. We found nonlinear, power-law relationships between the environmental and tissue concentrations of the elements, which may explain differences in bioaccumulation factors (BAF) reported in the literature. Tissue concentrations were driven by the environmental concentrations in non-essential elements (Al, As, Co, Cr, Ni, Pb and V), but this dependence was limited in essential elements (Cu, Mn, Se and Zn). Tissue concentrations of most elements were also more closely related to substrate than to water concentrations. Bioaccumulation was habitat specific in eight elements: stronger in mining ponds for Al and Pb, and stronger in fly ash lagoons for As, Cu, Mn, Pb, Se, V and Zn, although the differences were often minor. Bioaccumulation of some elements further increased in mineral-rich localities. Proximity to substrate, rather than trophic level, drove increased bioaccumulation levels across taxa. This highlights the importance of substrate as a pollutant reservoir in standing freshwaters and suggests that benthic taxa, such as molluscs (e.g., Physella) and other macroinvertebrates (e.g., Nepa), constitute good bioindicators. Despite the higher environmental risks in fly ash lagoons than in mining ponds, the observed ability of freshwater biota to sustain pollution supports the conservation potential of post-industrial sites. The power law approach used here to quantify and disentangle the effects of various bioaccumulation drivers may be helpful in additional contexts, increasing our ability to predict the effects of other contaminants and environmental hazards on biota.info:eu-repo/semantics/publishedVersio

Processing of the VP1/2A Junction Is Not Necessary for Production of Foot-and-Mouth Disease Virus Empty Capsids and Infectious Viruses: Characterization of “Self-Tagged” Particles

The foot-and-mouth disease virus (FMDV) capsid protein precursor, P1-2A, is cleaved by 3C(pro) to generate VP0, VP3, VP1, and the peptide 2A. The capsid proteins self-assemble into empty capsid particles or viruses which do not contain 2A. In a cell culture-adapted strain of FMDV (O1 Manisa [Lindholm]), three different amino acid substitutions (E83K, S134C, and K210E) were identified within the VP1 region of the P1-2A precursor compared to the field strain (wild type [wt]). Expression of the O1 Manisa P1-2A (wt or with the S134C substitution in VP1) plus 3C(pro), using a transient expression system, resulted in efficient capsid protein production and self-assembly of empty capsid particles. Removal of the 2A peptide from the capsid protein precursor had no effect on capsid protein processing or particle assembly. However, modification of E83K alone abrogated particle assembly with no apparent effect on protein processing. Interestingly, the K210E substitution, close to the VP1/2A junction, completely blocked processing by 3C(pro) at this cleavage site, but efficient assembly of “self-tagged” empty capsid particles, containing the uncleaved VP1-2A, was observed. These self-tagged particles behaved like the unmodified empty capsids in antigen enzyme-linked immunosorbent assays and integrin receptor binding assays. Furthermore, mutant viruses with uncleaved VP1-2A could be rescued in cells from full-length FMDV RNA transcripts encoding the K210E substitution in VP1. Thus, cleavage of the VP1/2A junction is not essential for virus viability. The production of such engineered self-tagged empty capsid particles may facilitate their purification for use as diagnostic reagents and vaccines