Suchergebnisse

The method of applying passive diffusive samplers for research on air quality is simple, easy enough and requires no electricity. The operating principle of almost all passive samplers is based on chemical reactions taking place on absorbent (impregnated filter or grid). The pollutant absorption mechanism is based on passive diffusion through the gas diffusion layer to absorbent. The diffusion process can be explained by first Fick's law described as a free movement of gases from the ambient air to a passive sampler. This movement depends on pollutant gradient. The aim of this paper is to analyse the influence of an impregnating solution on the efficiency of diffusive samplers. The object of the study covers the triethanolamine (TEA) aqueous solutions of 5%, 10%, 20%, 30% and 50%. The results obtained showed that 30% and 50% aqueous solution gave 68% and 89% relative error making the true meaning of the oxides of nitrogen analyzer testimony. Data on the passive samplers impregnated with TEA aqueous solutions having concentrations of 5%, 10% and 20% are within definite 25% uncertainty established by the European Union Directives. Article in Lithuanian. Impregnuojančio tirpalo įtakos difuzinių kaupiklių efektyvumui eksperimentiniai tyrimai Santrauka.Pasyvusis oro tyrimų metodas – paprastas, nesudėtingas, elektros energijos nereikalaujantis oro kokybės nustatymo metodas. Beveik visų pasyviųjų kaupiklių veikimo principas pagrįstas cheminėmis reakcijomis, vykstančiomis ant sorbavimo elemento (impregnuoto filtro ar tinklelio). Teršalo sugėrimo mechanizmas pasyviajame kaupiklyje pagrįstas dujų difuzija per difuzinį sluoksnį iki sorbavimo elemento. Difuzijos procesas aprašomas pirmuoju Fiko (Fick) dėsniu, t. y. laisvu dujų ar dalelių judėjimu iš analizuojamosios terpės į kaupiklį dėl teršalo koncentracijų gradiento. Šiame darbe nagrinėjama impregnuojančių tirpalų įtaka difuzinio kaupiklio efektyvumui. Tyrimų objektas – skirtingų koncentracijų trietanolamino (TEA) vandeniniai tirpalai azoto dioksidui nustatyti pasyviaisiais kaupikliais. Gauti rezultatai parodė, kad 30 % ir 50 % vandeniniai tirpalai lemia 68 % ir 89 % santykines paklaidas, tikrąja azoto dioksido reikšme laikant analizatoriaus rodmenis. 5 %, 10 % ir 20 % koncentracijų TEA vandeniniais tirpalais impregnuotų pasyviųjų kaupiklių tyrimų rezultatai neviršijo Europos Sąjungos direktyvoje nustatytos 25 % neapibrėžties, nustatant azoto dioksido koncentraciją indikatoriniais metodais. Reikšminiai žodžiai: azoto dioksidas, difuzinis kaupiklis, impregnavimo tirpalas, trietanolaminas.

The method of applying passive diffusive samplers for research on air quality is simple, easy enough and requires no electricity. The operating principle of almost all passive samplers is based on chemical reactions taking place on absorbent (impregnated filter or grid). The pollutant absorption mechanism is based on passive diffusion through the gas diffusion layer to absorbent. The diffusion process can be explained by first Fick's law described as a free movement of gases from the ambient air to a passive sampler. This movement depends on pollutant gradient. The aim of this paper is to analyse the influence of an impregnating solution on the efficiency of diffusive samplers. The object of the study covers the triethanolamine (TEA) aqueous solutions of 5%, 10%, 20%, 30% and 50%. The results obtained showed that 30% and 50% aqueous solution gave 68% and 89% relative error making the true meaning of the oxides of nitrogen analyzer testimony. Data on the passive samplers impregnated with TEA aqueous solutions having concentrations of 5%, 10% and 20% are within definite 25% uncertainty established by the European Union Directives. Article in Lithuanian Impregnuojančio tirpalo įtakos difuzinių kaupiklių efektyvumui eksperimentiniai tyrimai Santrauka Pasyvusis oro tyrimų metodas – paprastas, nesudėtingas, elektros energijos nereikalaujantis oro kokybės nustatymo metodas. Beveik visų pasyviųjų kaupiklių veikimo principas pagrįstas cheminėmis reakcijomis, vykstančiomis ant sorbavimo elemento (impregnuoto filtro ar tinklelio). Teršalo sugėrimo mechanizmas pasyviajame kaupiklyje pagrįstas dujų difuzija per difuzinį sluoksnį iki sorbavimo elemento. Difuzijos procesas aprašomas pirmuoju Fiko (Fick) dėsniu, t. y. laisvu dujų ar dalelių judėjimu iš analizuojamosios terpės į kaupiklį dėl teršalo koncentracijų gradiento. Šiame darbe nagrinėjama impregnuojančių tirpalų įtaka difuzinio kaupiklio efektyvumui. Tyrimų objektas – skirtingų koncentracijų trietanolamino (TEA) vandeniniai tirpalai azoto dioksidui nustatyti pasyviaisiais kaupikliais. Gauti rezultatai parodė, kad 30 % ir 50 % vandeniniai tirpalai lemia 68 % ir 89 % santykines paklaidas, tikrąja azoto dioksido reikšme laikant analizatoriaus rodmenis. 5 %, 10 % ir 20 % koncentracijų TEA vandeniniais tirpalais impregnuotų pasyviųjų kaupiklių tyrimų rezultatai neviršijo Europos Sąjungos direktyvoje nustatytos 25 % neapibrėžties, nustatant azoto dioksido koncentraciją indikatoriniais metodais. Reikšminiai žodžiai: azoto dioksidas, difuzinis kaupiklis, impregnavimo tirpalas, trietanolaminas.

Carbon neutrality has become a goal of European Union countries as they held agreement on the European Green Deal; the goal needs to be achieved by 2050. To achieve this goal production industry plays major role as this sector produces considerable amount of greenhouse gas emissions. This paper analyses processes within fish processing industry as the consumption of fish products has increased; therefore, production rate in this area also has been growing. Even more, the consumption of fish products per capita is forecasted to keep increasing for at least the next further years as fish products are great protein source. Thus, it is important to improve efficiency in the fish processing industry, to reduce the amount of emissions, waste and pollution produced in the industry, to evaluate the use of water and energy as well as the resources used in order to achieve sustainable production and carbon neutrality. Data envelopment multicriteria analysis method was used in this research to evaluate energy efficiency in the fish processing industry within sterilization process. The results have shown that the full water immersion autoclave an

Carbon neutrality has become a goal of European Union countries as they held agreement on the European Green Deal; the goal needs to be achieved by 2050. To achieve this goal production industry plays major role as this sector produces considerable amount of greenhouse gas emissions. This paper analyses processes within fish processing industry as the consumption of fish products has increased; therefore, production rate in this area also has been growing. Even more, the consumption of fish products per capita is forecasted to keep increasing for at least the next further years as fish products are great protein source. Thus, it is important to improve efficiency in the fish processing industry, to reduce the amount of emissions, waste and pollution produced in the industry, to evaluate the use of water and energy as well as the resources used in order to achieve sustainable production and carbon neutrality. Data envelopment multicriteria analysis method was used in this research to evaluate energy efficiency in the fish processing industry within sterilization process. The results have shown that the full water immersion autoclave an