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Number of results: 4
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Abstract

Dust generated at an electric arc furnace during steel production industry is still not a solved problem. Electric arc furnace dust (EAF) is a hazardous solid waste. Sintering of well-prepared briquetted mixtures in a shaft furnace is one of possible methods of EAFD utilisation. Simultaneously some metal oxides from exhaust gases can be separated. In this way, various metals are obtained, particularly zinc is recovered. As a result, zinc-free briquettes are received with high iron content which can be used in the steelmaking process. The purpose of the research was selecting the appropriate chemical composition of briquettes of the required strength and coke content necessary for the reduction of zinc oxide in a shaft furnace. Based on the results of the research the composition of the briquettes was selected. The best binder hydrated lime and sugar molasses and the range of proper moisture of mixture to receive briquettes of high mechanical strength were also chosen and tested. Additionally, in order to determine the thermal stability for the selected mixtures for briquetting thermal analysis was performed. A technological line of briquetting was developed to apply in a steelworks.

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Authors and Affiliations

Aneta Magdziarz
Monika Kuźnia
Michał Bembenek
Paweł Gara
Marek Hryniewicz
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Abstract

There were done simulations of fuels consumption in the system of electrical energy and heat production based on modernised GTD-350 turbine engine with the use of OGLST programme. In intention the system based on GTD-350 engine could be multifuel system which utilise post-fying vegetable oil, micronised biomass, sludge, RDF and fossil fuels as backup fuels. These fuels have broad spectrum of LHV fuel value from 6 (106 J·kg-1) (e.g. for sludge) to 46 (106 J·kg-1) (for a fuel equivalent with similar LHV as propan) and were simulations scope. Simulation results showed non linear dependence in the form of power function between unitary fuel mass consumption of simulated engine GTD-350 needed to production of 1 kWh electrical energy and LHV fuel value (106 J·kg-1). In this dependence a constant 14.648 found in simulations was multiplied by LHV raised to power –0.875. The R2 determination coefficient between data and determined function was 0.9985. Unitary fuel mass consumption varied from 2.911 (kg·10–3·W–1·h–1) for 6 (106 J·kg-1) LHV to 0.502 (kg·10–3·W–1·h–1) for 46 (106 J·kg-1) LHV. There was assumed 7,000 (h) work time per year and calculated fuels consumption for this time. Results varied from 4,311.19 (103 kg) for a fuel with 6 (106 J·kg-1) LHV to 743.46 (103 kg) for a fuel with 46 (106 J·kg-1) LHV. The system could use fuels mix and could be placed in containers and moved between biomass wastes storages placed in many different places located on rural areas or local communities.
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Authors and Affiliations

Marek Hryniewicz
1
ORCID: ORCID
Kamil Roman
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences – National Research Institute, Falenty, Hrabska Av. 3, 09-090 Raszyn, Poland
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Abstract

This study aimed to investigate how great cormorants and grey herons affect the density and trophic diversity of soil nematodes under breeding colonies located in Stawy Raszyńskie Nature Reserve (central Poland). Soil samples from the colonies were compared to control samples from adjacent areas unaffected by birds. Samples were taken at each site (two colonies and two relevant control sites) to a depth of 20 cm, and the soil cores were split into topsoil (0–10 cm) and subsoil (10–20 cm). A modified Baermann method was used to extract nematodes from the soil. The soil under nests supported more abundant nematode communities, but with a lower trophic diversity compared to the control sites. The cormorants had a greater impact on nematodes than the herons. We found that the external nitrogen input, the higher organic matter content and abundance of ammonifying bacteria, as well as the lower soil pH under the colonies than in the control sites, affected the nematode trophic groups in different ways. Compared to the control sites, there were significantly more bacterivorous nematodes but fewer herbivorous nematodes under the colonies. No predatory nematodes were found under the bird colonies and, in the case of the cormorant colony, no omnivorous nematodes. No significant differences in the abundance of fungivorous nematodes between the impact and the control plots were noticed. The results indicate that allochthonous input under bird colonies promotes microbial activity and the most opportunistic trophic group of nematodes, which may at least temporarily enhance decomposition and mineralisation processes and consequently affect nutrient cycling in the wetland soil.
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Authors and Affiliations

Dawid Kozacki
1
ORCID: ORCID
Krassimira Ilieva-Makulec
2
ORCID: ORCID
Marek Hryniewicz
3
ORCID: ORCID
Grzegorz Makulec
2

  1. National Institute of Horticultural Research, Department of Plant Protection, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland
  2. Cardinal Stefan Wyszynski University in Warsaw, Institute of Biological Sciences, Warsaw, Poland
  3. Institute of Technology and Life Sciences – National Research Institute, Falenty, Poland
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Abstract

Models describe our beliefs about how the world functions. In mathematical modelling, we translate those beliefs into the language of mathematics. Mathematical models can yield prognose on the base of applied fertiliser dose. In this work results of finding yield mathematical model according to fertiliser (nitrogen) dose for perennials (willowleaf sunflower Helianthus salicifolious, cup plant Silphium perfoliatum and Jerusalem artichoke Helianthus tuberosus) on marginal land are presented. Models were described as normalised square equations for dependence between yield and fertiliser doses. Experiments were conducted in lisymeters and vases for willowleaf sunflower and cup plant. For Jerusalem artichoke experiments were done in vases only. All experiments have been doing during two years (2018 and 2019) for different fertilisers doses (45, 90 and 135 kg N∙ha–1) in three repetitions. From simulations maximal yield could be achieved for following fertiliser doses – willowleaf sunflower 104 kg N∙ha–1, cup plant 85 kg N∙ha–1 and Jerusalem artichoke 126 kg N∙ha–1.
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Authors and Affiliations

Marek Hryniewicz
1
ORCID: ORCID
Maria Strzelczyk
1
ORCID: ORCID
Marek Helis
1
ORCID: ORCID
Anna Paszkiewicz-Jasińska
1
ORCID: ORCID
Aleksandra Steinhoff-Wrzesniewska
1
ORCID: ORCID
Kamil Roman
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences – National Research Institute, Falenty, Hrabska Av. 3, 09-090 Raszyn, Poland

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