Jerzy Florian Chojnacki

Prof. Jerzy Florian Chojnacki

Koszalin University of Technology, Faculty of Mechanical Engineering
orcid

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 August 2020 in Energies
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Journal Article
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JCJerzy Florian Chojnacki
Jerzy Florian Chojnacki
JNJan Najser
Jan Najser
Krzysztof RokoszKrzysztof Rokosz
Krzysztof Rokosz
VPVaclav Peer
Vaclav Peer
JKJan Kielar
Jan Kielar
BBBogusława Berner
Bogusława Berner
Investigations were performed in relation to the thermal gasification of wood granulate using steam in an allothermal reactor with electric heaters. They studied the impact of the temperature inside the reactor and the steam flow rate on the percentage shares of H2, CH4, CO, and CO2 in synthesis gas and on the calorific value of syngas. The tests were conducted at temperatures inside the reactor equal to 750, 800, and 850 °C and with a steam flow rate equal to 10.0, 15.0, and 20.0 kg∙h−1. The intensity of gasified biomass was 20 kg∙h−1. A significant impact of the temperature on the percentages of all the components of synthesis gas and a significant impact of the steam flow rate on the content of hydrogen and carbon dioxide in syngas were found. The highest percentage of hydrogen obtained was 43.3%. The calorific value of the gas depended significantly on the temperature inside the reactor and the correlation between the temperature and the steam flow rate. Its maximum value was 13.3 MJ∙m−3 at 800 °C. This paper also includes an assessment of the mutual correlations of the percentage shares of the individual synthesis gas components.

13 January 2021 in Energies
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JCJerzy Florian Chojnacki
Jerzy Florian Chojnacki
AZAgnieszka Zdanowicz
Agnieszka Zdanowicz
JOJuraj Ondruška
Juraj Ondruška
ĽŠĽubomír Šooš
Ľubomír Šooš
MSMałgorzata Smuga-Kogut
Małgorzata Smuga-Kogut
Influence of wastes generated during juice production: apple, carrot and red beet, added to barley straw, on density of pellet mass, pellet hardness, ash content and calorific value was assessed. Dry mass content of additives in the substrate to pellet production was: 0, 10, 20 and 30% of the mixture weight. The relative humidity of the raw material was: 17.0, 19.5 and 22%. Higher percentages of additives and higher moisture content in the raw materials increased the hardness and density of the pellet. The contents of natural polymers such as lignin, hemicellulose and cellulose were determined in primary materials used to prepare substrate and in pellet. Changes in the determination of these substances was observed as a result of the granulation process.

22 November 2017
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Conference Paper
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BBBogusława Berner
Bogusława Berner
JCJerzy Florian Chojnacki
Jerzy Florian Chojnacki

4 November 2021 in Agriculture
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JCJerzy Florian Chojnacki
Jerzy Florian Chojnacki
APAleksandra Pachuta
Aleksandra Pachuta
Research was carried out concerning spraying young cherry trees with a multirotor drone: a hexacopter. The aim of the study was to evaluate the impact of the following: the nozzle type, the air stream from the drone rotors and the size of spacing between the trees on the distribution of the liquid sprayed in the crown of the trees being sprayed. Experimental trials were conducted on a laboratory test stand. Air-injector spray nozzles: single and a twin flat were used interchangeably to spray the liquid. The travelling speed of the drone was 1.0 m∙s−1. A drone of 106.7 N weight was accepted in the study. The value of the spray liquid deposited and the uniformity of the liquid deposition in the crowns of the trees as well as the transverse distribution of the liquid under the nozzles were evaluated. It was found that the air stream from the drone rotors increased the distribution of the liquid on the trees sprayed, mainly at the middle and lower levels of the crown. A higher deposition value of the liquid was sprayed from the twin flat nozzle than from the single flat nozzle. There was no significant effect of the difference in the distance between the trees, of 0.5 and 1.0 m, on the liquid distribution. Under the influence of the air jet, the uniformity of the liquid distribution in the crowns of the trees also improved.

13 May 2022 in Materials
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TNTomáš Najser
Tomáš Najser
BGBłażej Piotr Gaze
Błażej Piotr Gaze
BKBernard Knutel
Bernard Knutel
AVAdam Verner
Adam Verner
JNJan Najser
Jan Najser
ONOndřej Němček
Ondřej Němček
This paper presents the research results of the effect of using calcium oxide and potassium permanganate on the combustion of pellets from wheat bran and beet pulp. The measurements were performed in the technical laboratory of the Centre of Energy Utilization of Non-Traditional Energy Sources in Ostrava. The research examined the effect of the use of chemical substances on the amount of air pollutants from biomass thermal conversion in a low-power boiler and the process temperature. First, we performed technical and elementary analyses of agricultural waste. The raw material was then comminuted, mixed with a selected additive, pelletized, and finally burned in a low-power boiler. The additive was added in three proportions: 1:20, 1:10, and 1:6.67 (i.e., 15%) relative to the fuel weight. The combustion process efficiency was measured using a flue gas analyzer and three thermocouples attached to the data recorder. From the measurement results, we were able to determine the percentage reduction of pollutant emissions into the atmosphere (CO, NOx, and SO2) due to the use of additives. Because emission standards are becoming increasingly stringent and fuel and energy prices are rising, the results presented in this article may be useful to agri-food processing plants that want to manage these materials thermally.

7 February 2022 in Materials
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Journal Article
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JCJerzy Florian Chojnacki
Jerzy Florian Chojnacki
JKJan Kielar
Jan Kielar
Leon KukiełkaLeon Kukiełka
Leon Kukiełka
TNTomáš Najser
Tomáš Najser
APAleksandra Pachuta
Aleksandra Pachuta
VPVaclav Peer
Vaclav Peer
Granulated beet pulp and wheat straw, first separately and then mixed in a weight ratio of 50/50%, underwent a pyrolysis process in a laboratory batch generator with process temperatures of 400 and 500 °C. The feedstock’s chemical composition and the pyrolysis products’ chemical composition (biochar and pyrolysis gas) were analysed. A synergistic effect was observed in the co-pyrolysis of the combined feedstock, which occurred as an increase the content of the arising gas in relation to the total weight of the products. and as a reduction of bio-oil content. The maximum gas proportion was 21.8% at 500 °C and the minimum between 12.6% and 18.4% for the pyrolysis of individual substrates at 400 °C. The proportions of the gases, including CO, CO2, CH4, H2, and O2, present in the resulting synthesis gases were also analysed. The usage of a higher pyrolysis final temperature strongly affected the increase of the CH4 and H2 concentration and the decrease of CO2 and CO concentration in the pyrolysis gas. The highest percentage of hydrogen in the synthesis gas, around 33%vol, occurred at 500 °C during co-pyrolysis.