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Remediacja środowiska gruntowo-wodnego na terenie stacji dystrybucji paliw metodą in situ

Kamiński A., Pusz A., Drewniak Ł.

Przemysł Chemiczny

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2018

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T. 97, nr 9

1575--1579

PL

W latach 2004-2009 na terenie dystrybucji paliw przeprowadzono prace związane z oczyszczaniem środowiska gruntowo-wodnego, pozostawiając teren do samooczyszczania przy pomocy obecnych w gruncie mikroorganizmów. Jednocześnie przeprowadzano analizy wód dwa razy w roku. Wahania poziomu zwierciadła wody gruntowej spowodowały pionowe przemieszczanie się warstwy zanieczyszczeń, stanowiąc źródło wtórnego zanieczyszczenia ziemi frakcjami rozpuszczalnymi. Wyniki badań wód gruntowych wykazały przekroczone dopuszczalne stężenia BTEX oraz związków ropopochodnych, wskazując na słaby stan chemiczny badanych wód. Stwierdzono, że teren ten należy poddać remediacji polegającej na przeprowadzeniu zabiegów inżynieryjnych, takich jak oczyszczanie wód gruntowych, wentylacja ziemi, bioremediacja stymulowana powietrzem wraz z biostymulacją i bioaugmentacją środowiska gruntowo-wodnego.

EN

Contents of Cd and Pb as well as C6-C12, C12-C35 hydrocarbon fractions and aromatic hydrocarbons in groundwater samples, taken from 4 boreholes, were detd. using at. emission spectrometry with excitation in induced plasma and gas chromatog., resp. Based on the anal. results, the quality classes of the tested water samples were detd. in accordance with sp. national legal regulations. Water samples from 2 drilling holes were highly polluted and addnl. technol. boreholes for pumping the polluted water, water treatment stations, pump systems as well as multifunctional boreholes for ventilation, aeration and biopreparations were recommended to protect the environment.

2

Określenie stanu gleby na terenie stacji dystrybucji paliw dla jej potencjalnej remediacji

Kamiński A., Pusz A., Drewniak Ł.

Przemysł Chemiczny

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2018

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T. 97, nr 3

410--415

PL

Dokonano oceny stanu fizyczno-chemicznego środowiska gruntowego na terenie obiektu dystrybucji docelowej paliw w aspekcie potencjalnej remediacji badanego terenu. Oznaczono wybrane właściwości fizyczne i chemiczne gleb, w tym zawartość lotnych węglowodorów aromatycznych (BTEX), sumy węglowodorów C6–C12 i C12–C35 oraz wielopierścieniowych węglowodorów aromatycznych (WWA). Dodatkowo oznaczono liczebność bakterii heterotroficznych oraz aktywność naturalnej mikroflory. Stwierdzono, że głównym typem zanieczyszczeń środowiska gruntowego na badanym terenie są benzyny i oleje, jak również BTEX oraz naftalen. Uzyskane wyniki świadczą o wysokim potencjale biodegradacyjnym naturalnej mikroflory, a w kontekście przeprowadzonych analiz chemicznych wskazują na możliwość skutecznej bioremediacji poprzez biostymulację autochtonicznej mikroflory.

EN

C6–C12 and C12–C35 hydrocarbon fractions and aromatic hydrocarbons were sep. extd. from soil samples with MeOH, hexane and CH2Cl2, resp. Then exts. were analyzed by gas chromatog. coupled to a mass spectrometer, and the obtained results were compared with the permissible concn. of pollutants in the soil. In addn., the abundance of heterotrophic bacteria after incubation (room temp., time 72 h) and microflora activity (dehydrogenase, lipase, cellulase) were estd. for soil samples. For most of them, the contents of both hydrocarbon fractions as well as alkylbenzenes and naphthalene were above the permissible values while abundance of heterotrophic bacteria and microflora activity was slightly below for soil values without contaminations of petroleum products.

3

Arsenic interactions with bog iron ores – As(III) and As(V) adsorption-desorption study

Tuchowska M., Bajda T., Rzepa G., Dębiec K., Drewniak Ł.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 1

133--134

EN

Arsenic is a toxic element, elevated concentration of which in the environment can result from both anthropogenic activity and natural geochemical processes. The contamination of water, especially groundwater, with As has been recognized as a major environmental problem (Choong et al. 2007). The mobility and toxicology of As is related to its valence state which can be (+III) or (+V), depending mainly on pH and redox conditions. Because even low As concentrations in drinking water causes severe health effects, the technologies of its effective removal are thought to be very important (Mohan & Pittman 2007). Among many methods developed for removing aqueous arsenic species, the adsorption onto iron oxyhydroxides or oxyhydroxide-rich sorbents is one of the most effective. Despite many studies, the factors affecting the adsorption processes, especially those related to the sorbent properties, are still far from being fully understood (e.g. Adra et al. 2016). In this work we investigated As(III) and As(V) adsorption and desorption by bog iron ores – natural ferruginous sediments which have been recently demonstrated to exhibit very good sorption properties. For this study four samples of bog iron ores, were collected at different sites in the Polish Lowlands: Kolechowice (KOL), Biadaszki (BD), Strzyżew (ST) and Dębe Małe (DM). They represent different bog iron ore types which, in spite of having diversified structures, mineral composition and, subsequently, physical and chemical properties, revealed good sorption affinities for trace elements in previous work (Rzepa et al. 2009). In batch experiments the influence of various factors on adsorption were studied, including initial As concentrations, initial pH values and competitive adsorption of As(III) and As(V). The effect of initial As concentrations was studied in the range of 0.01–20 mM As(III) or As(V) at pH 7.5. The influence of pH was evaluated by the adsorption of 5 mM As solution in the pH range of 2–12. The experiment of competitive adsorption of arsenite and arsenate was performed for various proportion of As(III) to As(V) in the range of initial concentrations 0.025–20 mM at pH 7.5. The bonding strength of As with bog iron ore surface was estimated on the basis of three-step desorption experiments, which were conducted for the samples previously treated with As(III) or As(V) at pH 7.5 and at constant 20 mM initial concentration of arsenic. Arsenic concentrations in filtered (filter with a 0.22 μm pore size) solutions after all the experiments were analyzed using AAS and UV-Vis spectrophotometry. The results showed that arsenic sorption depends on its oxidation state. All the bog iron ores bound more As(III) than As(V). The highest amount of As(III) was sorbed by ST sample (458 mmol/kg), lower by KOL (430 mmol/kg) and DM (427 mmol/kg), and the lowest by BD (333 mmol/kg). However, in the case of As(V), the order was different: the highest amount of As was sorbed by BD sample (264 mmol/kg), lower by ST (218 mmol/kg), and the lowest by DM (163 mmol/kg) and KOL (158 mmol/kg). The highest uptake (80–95%) of As(III) was noted at lower initial concentrations, while the highest uptake (60–70%) of As(V) was observed at higher initial concentrations. As(III) sorption effectiveness was >80% throughout the pH range of 4 to 9 and was almost independent on pH in that range. In contrast, the As(V) sorption was higher at slightly acidic pH and significantly decreased in alkaline conditions. At pH around 3, sorption efficiency of both As(III) and As(V) decreased, which is likely due to the increased solubility of iron oxyhydroxides (Zeng, 2004). The results of competitive sorption experiments revealed that at low concentrations of both As species reduction of sorption efficiency of As(III) occurred. Sorption of As(V) was also affected, but only if amount of As(III) was higher than As(V). On the contrary, at high As(V) and As(III) concentrations, As(V) did not influence As(III) sorption, but As(III) substantially increased sorption of As(V). Desorption of arsenic by foreign ligands resulted in extraction of more than 70% of absorbed As(III) and As(V). In the absence of the exchange ligand, i.e., in deionized water, desorption of As(V) and As(III) was considerably lower, but noticeable. This study shows that bog iron ores are very good arsenic sorbents. However, the extent of As removal seems to be affected by various factors including As species and the composition of the ores themselves. As(V) is immobilized less effectively than As(III), and the process is influenced by pH values. It is believed, that the uptake of As by bog ores is controlled primarily by iron oxyhydroxides, as main components of these rocks, but mechanisms predominant in As(III) and As(V) adsorption are different and affected by presence of e.g. phosphate and silicate ions (Ociński et al. 2011). There are no simple correlations between mineralogy and sorption capacity. Due to the variability in chemical and mineral composition of different types of bog iron ores, various levels of arsenic removal can be obtained. Such properties of the ores, combined with their ubiquity in many near-surface environments may be regarded as an incentive for the environmental protection practice.

4

Badania procesu fermentacji metanowej z wykorzystaniem metod radioznacznikowych i technik gamma skaningu

Palige J., Roubinek O., Wawryniuk K., Modzelewski Ł, Jakowiuk A., Dobrowolski A., Drewniak Ł., Ciężkowska M

Inżynieria i Aparatura Chemiczna

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2014

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Nr 4

280--281

PL

Określono metodami radioznacznikowymi, z wykorzystaniem trytu jako znacznika fazy ciekłej, rozkład czasu przebywania i średni czas retencji zawiesiny w bioreaktorach do produkcji biometanu. Wykorzystując technikę gamma skaningu określono objętość czynną fazy ciekłej, gazowej oraz obszar tworzenia się kożuchów.

EN

The residence time distribution and mean residence time of liquid phase in fermentor was determined using the tritium water as a radiotracer. With application of gamma scanning technique the volumes of liquid phase and foam in bioreactor were determined.

5

Analysis of MIS equivalent electrical circuit of Au/Pd/Ti-SiO2-GaAs structure based on DLTS measurements

Kochowski S., Drewniak Ł., Nitsch K., Paszkiewicz R., Paszkiewicz B.

Materials Science Poland

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2013

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Vol. 31, No. 3

446--453

EN

In this paper MIS equivalent electrical circuit of Au/Pd/Ti–SiO2–GaAs has been analyzed by a comparison of the results obtained from admittance and DLTS spectroscopy. Two groups of peaks with different magnitude and different gate voltage dependence have been observed in DLTS and admittance spectra. Based on the analysis of the peaks behavior, it has been concluded that they are associated with the response of bulk traps and interface states, respectively. In order to characterize bulk traps and interface states responsible for the occurrence of two groups of peaks in normalized conductance spectra we have used the equivalent circuit with two CPE-R branches. The time constant values estimated for both peaks from admittance analysis have been compared with the time constant determined from DLTS analysis. Some discrepancies have been noted between the time constants obtained for interface states whereas the time constants for bulk traps were compatible. It has been also demonstrated that when conductance peaks overlap, the admittance experimental data can be fitted by the equivalent electrical model with only one CPE-R branch. However, in this case incomplete information about the analyzed process has been obtained despite the fact that all model validity criteria can be fulfilled and the model seems to be correct.

6

System edukacyjny rozwiązywania wybranych ustrojów belkowych

Łoboda M., Krysztofiak A., Dworecki Z., Drewniak Ł., Mytkowski R.

Inżynieria Rolnicza

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2007

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R. 11, nr 2 (90)

167-174

PL

Praca dotyczy sytemu obliczającego reakcje i siły wewnętrzne (wraz z wykresami) dla wybranych układów belek i ram. Przejrzysty interfejs wraz z aktualizowanymi na bieżąco ilustracjami kolejnych kroków oraz panel nauki budowania równań równowagi podnosi walor edukacyjny programu.

EN

The work concerns the system of counting reactions and internal forces (together with graphs) for the chosen beam and frame structures. The clear interface together with on line actualize illustrations of sequence steps and the learning panel of building equilibrium equations raises the educational value of the programme.