59 research outputs found
An energy consumption approach to estimate air emission reductions in container shipping
Container shipping is the largest producer of emissions within the maritime shipping industry. Hence, measures have been designed and implemented to reduce ship emission levels. IMO's MARPOL Annex VI, with its future plan of applying Tier III requirements, the Energy Efficiency Design Index for new ships, and the Ship Energy Efficiency Management Plan for all ships. To assist policy formulation and follow-up, this study applies an energy consumption approach to estimate container ship emissions. The volumes of sulphur oxide (SOx), nitrous oxide (NOx), particulate matter (PM), and carbon dioxide (CO2) emitted from container ships are estimated using 2018 datasets on container shipping and average vessel speed records generated via AIS. Furthermore, the estimated reductions in SOx, NOx, PM, and CO2 are mapped for 2020. The empirical analysis demonstrates that the energy consumption approach is a valuable method to estimate ongoing emission reductions on a continuous basis and to fill data gaps where needed, as the latest worldwide container shipping emissions records date back to 2015. The presented analysis supports early-stage detection of environmental impacts in container shipping and helps to determine in which areas the greatest potential for emission reductions can be found
Evaluation of selected mechanical properties of biopolymers mouldings reinforced with flax fibers
W pracy przedstawiono rezultaty badań wpływu dodatku wypełniaczy w postaci
włókien lnianych na wytrzymałość mechaniczną oraz odkształcenie wyprasek biopolimerowych.
Do wytworzenia granulatu zastosowano zmodyfi kowany ekstruder jednoślimakowy
TS 45 o L/D = 18 z dodatkowym chłodzeniem końcowej części cylindra urządzenia.
Badano wpływ prędkości obrotowej ślimaka ekstrudera, ilości stosowanego wypełniacza
oraz temperatury wtrysku tworzywa na wybrane właściwości fi zyczne wyprasek biopolimerowych.
Zaobserwowano, że wypraski uzyskane z granulatów wytworzonych przy
wyższej prędkości obrotowej ślimaka ekstrudera oraz zwiększającym się udziale włókien
lnianych charakteryzowały się wyższą wytrzymałością mechaniczną. Dodatek włókien
lnianych zmniejszył wartość odkształcenia wyprasek z granulatów TPS.The research covered mechanical properties of mouldings of maize thermoplastic
starch (TPS) reinforced with fl ax fi ber. The thermoplastic starch granules were produced
from mixtures of maize starch, glycerol and fl ax fi bers in amount from 5 to 30%. In
the study, a modifi ed single-screw extruder TS-45 was used with L/D = 18 with an extra
cooling section of the last part of the cylinder. Stainless steel forming die was applied with
open 3 mm in diameter. TPS granulates were processed with extruder screw speed 60 and
100 rpm. Processing temperature was set in a range from 60 to 110°C. The tests of the
high-pressure injection process of TPS granulates reinforced with fl ax fi ber was done on
the injection moulding machine ARBURG 220H90-350, L/D = 20.5. Injection speed was
set at the level 70–90 mm·s–1, injection time was 5 s, processing temperature ranged from
100 to 160°C. Biopolymer samples shaped for standardized bone-type mouldings were
assessed for mechanical properties. Mechanical properties were evaluated with universal
testing machine Zwick BDO-FBO0,5TH (Ulm, Germany) equipped with 0.5 kN working
head. Test speed was 5 mm·min–1. Maximum tensile at break and maximum elongation of
mouldings were evaluated during elongation test. The research focused on the effect of the
extruder screw speed, injection temperature and the amount of fl ax fi bers applied for tensile
at break and elongation of mouldings. Maize starch samples processed without fi ber addition
characterized lower mechanical resistance during elongation tests. It was concluded
the highest tensile at break for mouldings with 30% of fl ax fi bers processed on the base of granulate extruded at 60 rpm and injected in temperature 140°C with value 32.5 MPa.
During the measurements, the higher values of tensile at break were reported for mouldings
with increasing of fl ax fi bers addition independently the injection temperature used.
Addition of fi bers signifi cantly infl uenced on biopolymer elongation. It was observed that
elongation lowered with increasing fl ax fi ber amount in the recipe. The highest values of
elongation were observed for maize mouldings without fi ber addition in a whole range of
injection temperature used. Samples reinforced with 30% of fl ax fi bers characterized the
highest stiffness. Maximum elongation of these mouldings reached 25% for samples processed
at injection temperature 140°C. Injection-moulding temperature had an insignifi cant
infl uence on mouldings elongation. Increasing amount of fl ax fi ber in biopolymer recipe
infl uenced on higher tensile at break and lowered elongation of tested mouldings
Effect of dietary supplementation with Echinacea purpurea on vaccine efficacy against infection with Flavobacterium columnare in zebrafish (Danio rerio)
The effect of dietary Echinacea purpurea (EP) on the response of zebrafish (Danio rerio) to a Flavobacterium columnare vaccine was investigated. Two hundred D. rerio with an average weight of 290 ± 40 g were selected and fed different levels of E. purpurea (5 g kg⁻¹ diet - group 1, 10 g kg⁻¹ diet - group 2, 20 g kg⁻¹ diet - group 3, 30 g kg⁻¹ diet - group 4, and 0 g kg⁻¹ diet - group 5). Experimental feeding was begun 3 weeks prior to bath immunization and continued until the end of the experiment. Twenty-eight days after immunization the fish were challenged by bath immersion with F. columnare at a concentration of 1x106 CFU/ml. The relative percent survival of the experimental groups (1, 2, 3, 4 and 5) was 5.0, 6.0, 30.0, 36.0 and 5.0, respectively. In conclusion, diet supplementation with E. purpurea may effectively enhance the response of zebrafish to a F. columnare vaccine
Wydajność i energochłonność procesu ekstruzji mieszanek ziemniaczanych oraz wielozbożowych
The aim of the research was to determine the effect of extrusion conditions (various moisture content of raw materials and screw rotation speed), as well as the effect of recipe composition on the process efficiency and the energy consumption during treatment of potato and multigrain products. The efficiency of the extrusion process (Q) was determined by the mass of the product obtained at a given time for all prepared raw material mixtures and the process parameters used, while the specific mechanical energy demand was determined using the SME index. The obtained results allow to conclude that the level of raw materials moisture content had a greater impact on the efficiency and energy consumption of the extrusion process than the variable screw speed during the treatment. The efficiency of the process increased with the increasing moisture of the tested compositions, while a decrease in the requirements of SME was observed. The use of differentiated raw material compositions also influenced the Q and SME values determined during the tests.Celem badań było określenie wpływu warunków obróbki mieszanki podczas procesu ekstruzji (zróżnicowana wilgotność mieszanek surowcowych i prędkość obrotów ślimaka), jak również wpływ kompozycji receptury na wydajność procesu i zużycie energii podczas produkcji pelletów z surowców ziemniaczanych oraz produktu typu multigrain. Wydajność procesu ekstruzji (Q) wyznaczano przez określenie masy produktu uzyskanego w określonym czasie dla wszystkich przygotowanych mieszanek surowcowych oraz zastosowanych parametrów procesu, natomiast jednostkowe zapotrzebowanie energii zostało określone przy użyciu wskaźnika SME (ang. specific mechanical energy). Uzyskane wyniki pozwalają stwierdzić, że poziom dowilżenia mieszanek surowcowych miał większy wpływ na wydajność i energochłonność procesu ekstruzji niż zmiana prędkości ślimaka podczas wytłaczania. Wydajność procesu wzrastała wraz ze wzrostem wilgotności mieszanki, natomiast zaobserwowano spadek zapotrzebowania energii mechanicznej. Zastosowanie zróżnicowanych receptur surowcowych również wpłynęło na wartości Q i SME wyznaczone podczas badań. Mniejszą wydajność oraz większe SME odnotowano przy zastosowaniu mieszanki typu multigrain
Effect of flax fibers addition on the mechanical properties and biodegradability of biocomposites based on thermoplastic starch
The research was intended to develop a biocomposite as an alternative biodegradable material, for the production of, e.g., disposable utensils. The author’s tested thermoplastic maize starch, both without additives and with the addition of crumbled flax fiber in the share of 10, 20 and 30 wt%. The plasticizer added was technical glycerin and the samples were produced by a single-screw extruder. The mechanical strength tests were performed, including the impact tensile test and three-point bending flexural test. Afterwards, the samples were tested for biodegradability under anaerobic conditions. The methane fermentation process was carried in a laboratory bioreactor under thermophilic conditions with constant mixing of the batch. All samples proved to be highly susceptible to biodegradation during the experiment, regardless of the flax fiber share. The biogas potential was about 600 ml·g-1, and the methane concentration in biogas ranged from 66.8 to 69.6%. It was found, that the biocomposites can be almost completely utilized in bioreactors during the biodegradation process. The energy recovery in the decomposition process with the generation of significant amount of methane constitutes an additional benefit
Zmiany energochlonnosci podczas ekstruzji skrobi ziemniaczanej
The simplest method of physical modifi cation of starch is extrusion-cooking. Changes of the extruder
efficiency and specific mechanical energy (SME) during extrusion-cooking of potato starch are presented in
the paper. Extrusion-cooking process was characterised by good efficiency. The output depended mainly on the
extruder screw speed and starch moisture content, less on process temperature. It ranged between the 11.3 kgh-1
and 28 kgh-1 depending on process parameters. SME measurements showed that extrusion-cooking of potato
starch is related with rather low energy input ranged from 0.083 to 0.275 kWhkg-1. Significant impact on the
values of the SME had a screw speed, very little impact had a moisture content of the raw material.Najprostszą metodą fizycznej modyfikacji skrobi jest ekstruzja. W pracy przedstawiono wyniki
pomiarów wydajności i energochłonności procesu ekstruzji skrobi ziemniaczanej. Proces ekstruzji skrobi ziemniaczanej
charakteryzował się wysoką wydajnością. Zmiany wydajności ekstrudera zależały głównie od zmian
prędkości obrotowej ślimaka ekstrudera i wilgotności skrobi, w mniejszym stopniu od temperatury procesu.
Wydajność zmieniała się w granicach 11.3-28 kgh-1 w zależności od zastosowanych parametrów procesu. Wyniki
badań wskazują, że procesu ekstruzji skrobi ziemniaczanej związany jest z relatywnie niską energochłonnością
(0.083-0.275 kWhkg-1). Znaczący wpływ na zmiany SME miała prędkość ślimaka ekstrudera, nieduży wpływ
miała wilgotność przetwarzanej skrobi
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