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1

Półciągła kofermentacja osadów ściekowych i odpadów tłuszczowych pochodzenia roślinnego

Grosser A., Worwąg M., Neczaj E., Grobelak A.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2108--2125

EN

Anaerobic digestion (AD) is the most often applied technique for sewage sludge stabilization at medium and large wastewater treatment plants. Nonetheless, the application of AD to sewage sludge stabilization is often limited by long retention time and low VS (volatile solid) removal. For this reason in recent years a number of studies have been focused on optimize anaerobic digestion processes. One of the most interesting options for improving anaerobic digestion yields is co-digestion, namely simultaneous decomposition of a homogenous mixture of at least two biodegradable wastes. Fat-rich materials are attractive substrate for AD due to the high organic matter content of waste and high energetic potential. It is estimated that about 1,014 dm3, methane at STP (standard temperature and pressure) can by produced from 1 g VS lipids, while only 0,415, 0,496 dm3 can be produced respectively from 1 g VS carbohydrate and protein. However, due to inhibitory eﬀect of intermediate compounds (LCFAs – long chain fatty acids) and operational problems, such as: hindrance, sedimentation clogging, scum formation, and flotation of biomass, separate AD of this waste ended with failure. The aim of the current study was to investigate how the co-digestion of fats of vegetable origin (FV) and mixed sewage sludge affected the performance of the anaerobic digestion (AD) process. The process was carried out at mesophilic conditions (37°C) in continuous stirred-tank reactor (CSTR) with working liquid volume equal to 6,5 dm3. The reactors were operated in draw-and fill mode (on a daily basis). The digestion was examined in semi-continuous mode at sludge retention time of 10 days and the organic loading rate maintained in the range 2,24–3,02 g/dm3 d. During the start-up period the digester was fed only sewage sludge. Co-digestion process was initiated after achievement of stable working parameters of bioreactor for sewage sludge digestion. Addition of fat in the feedstock was gradually increased up to 35%. Anaerobic process state indicators such as: biogas production, biogas composition, pH, alkalinity and volatile fatty acids (VFA) were used to monitor a digestion. Furthermore, the LCFAs concentrations were measured in a feed and digested sludge. The results showed that use of FV as a co-substrate adversely affects the efficiency of the process. Comparing digestion of MSS alone with co-digestion of wastes, it was shown that co-digestion resulted in lower biogas production and VS removal. Biogas yields for co-digestion mixtures were between 0,16 and0,32 dm3/g VS added, while volatile solid (VS) removal ranged from 36,75 to 42,65%.However average biogas yield and VS degradation degree observed during fermentation of the MSS(mixed sewage sludge) alone were 0,33 dm3/g VS added and 44%, respectively. Only for biogas composition noted the positive effect of mixed sewage sludge co-fermentation with FV. The study showed that the concentration of ammonia generated in this experiment did not inhibit anaerobic digestion. It was found that oleic acid, which is one of the most toxic long chain fatty acids, was present at concentrations (reached a maximum value of 34,38 mg/g TS) within the ranges for which inhibition of methanogenesis has been reported. This suggests that the low efficiency of the process was probably caused a high concentration of oleic acid.

2

Atomic structural templates of the earliest life on earth: vibration and lightning experiments with quartz and amino acids

Pawlikowski M.

Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering

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2012

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nr 14

1-8

EN

The atomic structure of minerals and organic molecules is remarkably similar. In particular, between minerals and amino acids, which are the building blocks of life on Earth. The hypothesis tested here is the possibility of energy transfer from minerals to amino acids, in the form of solar energy. The experiments tested the theory that the brighter intensity of light in the early Earth may have kick -started the chemical reactions needed for life. The scenario under investigation is that of light reacting with quartz sand grains exposed at the surface. The quartz grains contain water within the pore spaces, which has basic amino acid structures within in. The experiments determined that the vibration of piezoelectric quartz altered the structure of amino acid molecules.

3

Synthesis and evaluation of effectiveness of a controlled release preparation 2,4-D: a reduction of risk of pollution and exposure of workers

Kowalski W. J., Romanowska I., Smol M., Silowiecki A., Głazek M.

Archives of Environmental Protection

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2012

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Vol. 38, no. 3

119-129

EN

A novel herbicidal controlled release formulation composed of (2,4-dichlorophenoxy) acetic acid (2,4-D) chemically bonded to biodegradable (R,S)-3-hydroxybutyric acid oligomers was investigated. The synthesis of (R,S)-3-hydroxy butyric acid oligomers was carried out via the ring opening polymerization of â-butyrolactone initiated by 2,4-dichlorophenoxy acetic potassium salt in the presence of complexing agents. The formed oligomers were characterized by size exclusion chromatography, proton magnetic resonance and electrospray mass spectrometry in order to fi nd out their molar mass distribution and molecular structures. An assessment of biological effectiveness of the obtained herbicidal formulation was carried out in the greenhouse vs. Sinapis alba var. Nakielska. A promotion of the controlled release formulation with decreased water solubility and with low vapor pressure of the active ingredient, instead of traditional formulations of 2,4-dichlorophenoxy acetic acid may help to ensure a greater safety for workers and reduce the risk of dissemination of the active ingredient in the soil profile.

4

Role of plant litter in developing the content of phenolic compounds in humic substances

Banach-Szott M., Dębska B.

Ecological Chemistry and Engineering. A

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2009

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Vol. 16, nr 3

239-252

EN

The aim of the present paper was to determine the content of phenolic compounds in the extracts of fulvic acids and hydrolysates of humic acids depending on the properties of plant litter. The research involved sampling from organic and mineral horizons of forest soils located in the area of the Arboretum in Mlyniany in Slovakia. To identify and to determine the quantity of phenolic compounds the chromatographic method (HPLC) was used. The research demonstrated that the content of phenolic compounds in hydrolysates of fractions of humic acids was generally lower as compared with their content in the extracts of fulvic acids. The content of phenolic compounds both in the extracts of fulvic acids al)d in the hydrolysates of humie acids decreased with an increase in the degree of the organic matter transformation. It was also shown that the basic parameter which differentiated the properties of newly-formed humie acids under different tree species was the ratio of vanillyl, syringyl and cinnamyl compounds. The extracts of humus acids of Ol subhorizon on the oak stand demonstrated a similar share of vanillyl and syringyl compounds (40:42:18), while the extracts of humie acids of Ol subhorizon on the spruce and thuja stands showed a considerable advantage of vanillyl compounds.

PL

Celem pracy było określenie zawartości związków fenolowych w ekstraktach kwasów fulwowych i hydrolizatach kwasów huminowych w zależności od właściwości opadu roślinnego. Do badań pobrano próbki z poziomów organicznych i mineralnych gleb leśnych zlokalizowanych na terenie Arboretum w Mlynianach na Słowacji. Do identyfikacji oraz ilościowego oznaczania związków fenolowych zastosowano metodę chromatograficzną (HPLC). Wykazano, że zawartość związków fenolowych w hydrolizatach frakcji kwasów huminowych była generalnie mniejsza w porównaniu z ich zawartością w ekstraktach kwasów fulwowych. Zawartość związków fenolowych zarówno w ekstraktach kwasów fulwowych, jak i hydrolizatach kwasów huminowych zmniejszała się wraz ze wzrostem stopnia transformacji materii organicznej. Wykazano również, że podstawowym parametrem odróżniającym właściwości nowo powstałych kwasów humusowych pod różnymi gatunkami drzew jest stosunek jednostek wanilinowych, syryngowych i cynamonowych. Ekstrakty kwasów humusowych podpoziomu surowinowego (Ol) na stanowisku dębu cechowały się zbliżonym udziałem jednostek wanilinowych i syryngowych (40:42:18). Natomiast ekstrakty kwasów humusowych podpoziomu Ol na stanowiskach świerka i tui charakteryzowały się znaczną przewagą jednostek wanilinowych.

5

Analiza tworzenia się zagrożeń pożarowo-wybuchowych na instalacjach przerobu ropy naftowej, w wyniku samozapalenia się pirosiarczków. /cz. 2/ Zabezpieczenie instalacji przerobu ropy naftowej przed zagrożeniami wynikającymi z obecności pirosiarczków

Pofit-Szczepańska M., Majder-Łopatka M., Salamonowicz Z.

Bezpieczeństwo i Technika Pożarnicza

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2008

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Nr 1

131--141

PL

Analiza tworzenia się zagrożeń pożarowo-wybuchowych na instalacjach przerobu ropy naftowej, w wyniku samozapalenia się pirosiarczków. /cz.2. ochrona instalacji/. W drugiej części artykułu omówiono sposoby usuwania siarczkowych warstw piroforycznych z instalacji przerobu ropy naftowej, zwracając szczególną uwagę na chemiczne metody czyszczenia. Podano różne przykłady mieszanin czyszczących i mechanizm ich działania, sposoby użycia oraz wady i zalety poszczególnych środków.

EN

Analysis of the generation fire hazard in the petroleum industry as a result of the spontaneous heating of pyrosulfides. Part 2. Protection of petroleum installation. Methods for cleaning of the installation from pyrosulfides layers: mechanical and chemical are summarized in this paper. Particular attention is paid to the type of cleaning mixture.

6

Selective removal of transition metal ions in transport through polymer inclusion membranes with organophosphorus acids

Ulewicz M., Walkowiak W.

Environment Protection Engineering

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2005

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Vol. 31, nr 3-4

73-82

EN

Separation of transition metal ions from aqueous chloride solutions by transport through polymer inclusion membrane (PIM) process is presented. The competitive transport of equimolar mixtures of Zn(II) and Cd(II) as well as Zn(II), Cu(II), Co(II), Cd(II), and Ni(II) was investigated. The selective transport of metal ions from aqueous chloride source phase through PIM-containing cellulose triacetate (support), o?nitrophenyl pentyl ether (plasticizer) and organophosphorus acidic compounds, i.e. di(2-ethylhexyl)phosphoric acid (D2EHPA), di(2,4,4-trimethylpentyl)phosphinic acid (Cyanex 272), di(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex 301) and bis(2,4,4-trimethylpentyl)monothiophosphinic acid (Cyanex 302) as ion carriers, is shown. The influence of extractant nature on the selectvity and efficiency of cation transport has been examined. Zn(II) can be effectively removed from dilute aqueous chloride solutions containing equilmolar mixture of Zn(II) and Cd(II) ions in transport through PIMs with di(2,4,4-trimethylpentyl)phosphinic acids, bis(2,4,4-trimethylpentyl)monothiophosphinic acid or di(2-ethylhexyl)phosphoric acid as the ionic carriers into 1.0 M HCl as the receiving phase. The per cent removal of Zn(II) and Cd(II) ions increases with an increase in pH, but more efficient separation of Zn(II) than Cd(II) ions decreases with pH increase in the source phase. Zn(II) can be also effectively removed from dilute aqueous chloride solutions containing equimolar mixture of Zn(II), Cd(II), Cu(II), Co(II) and Ni(II) ions by its transport through PIMs with D2EHPA, Cyanex 272 and Cyanex 302. All ions investi-gated are effectively removed with di(2,4,4-trimethylpentyl)dithio-phosphinic acids (Cyanex 301) as the ionic carrier into 1.0 M HCl as the receiving phase. The per cent removal of all metal ions investigated increases with an increase in pH of solution in the source phase. The initial transport fluxes of all metal ions through PIM with Cyanex 272 increase with an increase in an initial chloride acid concentration in the receiving phase.

7

Zastosowanie lipaz w syntezie organicznej w środowisku bezwodnym

Chalecki Z., Plenkiewicz J.

Wiadomości Chemiczne

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1998

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[Z] 52, 7-8

545-568

EN

In nature the enzymatic reactions are conduced in aqueous media. However for the purpose of organic synthesis nonaqueous conditions such as organic solvents are more suitable regarding reagents stability and reaction equilibrium. Rapidly increasing number of enzyme-catalysed processes shows great possibility of this domain of chemistry. This review presents methods that have been used in lipase-catalysed esterifications and transenterifiacations in nonaqueous media. We show many examples of resolution of racemic alcohols and acids using different lipases in different reaction conditions. We also present a few examples of highly regioselective properties of lipases. There are descibed general principles that govern lipase-catalysed reactions and historical development of biocatalysis in organic synthesis. We hope that this review will be helpful for the investigators and students in solving their problems of enzymatic synthesis.