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Karakterizacija bioremedijacionih procesa u zemljištu i podzemnim vodama zagađenim naftom i derivatima na lokalitetu Ratno ostrvo / Characterisation of the bioremediation processes in soil and groundwater contaminated by oil and oil derivatives at the site of Ratno OstrvoRončević Srđan 01 June 2007 (has links)
<p>Predmet izučavanja ove disertacije je pasivna bioremedijacija naftom i derivatima nafte zagađenih podzemnih voda na lokalitetu Ratno ostrvo i pospešivanje procesa <br />bioremedijacije zemljišta i podzemne vode zagađenih naftom i derivatima nafte na laboratorijskom postrojenju u ciljusanacije ugroženog lokaliteta.</p><p>Praćenjem podzemnih voda granične zone izvorišta Ratno ostrvo i Rafinerije nafte utvrđeno je da je u podzemnoj vodi granične zone izvorišta Ratno ostrvo i Rafinerije nafte Novi Sad prisutan proces pasivnebioremedijacije, odnosno, da na pojavu ugljovodoničnog zagađenja u vodi sredina odgovara povećanjem brojnosti, pre svega, ugljovodonik-osidujućih i lipolitskih bakterija i bakterijske enzimatske aktivnosti, i dolazi do transformacije mineralnih ulja u polarna jedinjenja. U vodi većine praćenih objekata uočene su eksponencijalne i linearne funkcionalne zavisnosti bakterijske brojnosti i fosfatazne aktivnosti od koncentracije ugljovodoničnog zagađenja za koncentracije ukupnih ugljovodonika < 400 µg/l (najčešće < 200 µg/l). Visok nivo podzemnih voda i prisustvo dela zagađenja u gornjim slojevima zemljišta ukazuje nam na mogućnost primene fitoremedijacije navedenog područja, jer je deo zagađenja dostupan korenskom sistemu.</p><p>Ispitivanjem tehničke bioremedijacije zemljišta i podzemne vode zagađenih naftom i <br />derivatima nafte na laboratorijskom postrojenju utvrđeno je da dolazi do opadanja <br />koncentracije ukupnih ugljovodonika u zemljištu sa 38,2 na 14,6 g/kg i mineralnih ulja sa 27,0 na 10,2 g/kg (62%), što se može definisati jednačinom C=C<sub>0</sub>e<sup>-kt</sup>, gde je <br />konstanta brzine degradacije ugljovodonika k=0,0082 dan<sup>-1</sup>. U vodi je prisutan veliki <br />broj karboksilnih kiselinanastalih oksidacijom alkana (C10-19), kao i aromata (benzoeva kiselina, kao i benzaldehid), što ukazuje na proces biooksidacije ugljovodonika. Proces rastvaranja i emulgovanja nafte se pospešuje uvođenjem recirkulacije vode: određena je jednačina zavisnosti koncentracije ugljovodonika u vodenoj fazi od koncentracije u čvrstoj fazi, zavisno od brzine proticanja: C<sub>voda</sub>=(f<sup>*</sup>v+K<sub>0</sub>)C<sub>zemlja</sub>, gde je koeficijent ispiranja f=1400 s/m, a difuzioni koeficijent K<sub>0</sub>=6<sup>*</sup>10<sup>-4</sup>. Proces ispiranja nafte i derivata sa zemlje značajno utiče na aktivnost mikroorganizama i razgradnju zagađenja. Sa porastom koncentracije ugljovodonika generalno opadaju brojnosti svih ispitivanih grupa bakterija i fosfatazna aktivnost i određene su granične vrednosti tolerancije. Proces ispiranja se mora voditi tako da koncentracija mineralnih ulja u vodenoj fazi netreba da pređe 15-35 mg/l, a kad se postignu koncentracije ugljovodonika manje od 400 µg/l treba prepustiti pasivnoj bioremedijaciji da ukloni zagađenje.</p> / <p>This dissertation investigates the passivebioremediation of groundwater from Ratno Ostrvo contaminated by oil and oil derivatives, and a bench-scale experiment to improve the soil and groundwater bioremediation processes, with the goal of sanatising the effected area.</p><p>During groundwater monitoring of the zone between the Ratno Ostrvo spring and the Novi Sad oil refinery, a passive bioremediation process was observed, whereby, in the hydrocarbons-contaminated water, increased counts of hydrocarbon-oxidising and lipolytic bacteria and increasing bacterial enzyme activity were found, along with the transformation of mineral oils to polar compounds. In water, the majority of the monitoring points displayed either exponential or linear functionalal dependence between bacterial count or phosphatase activity and hydrocarbon concentration, for total hydrocarbon concentrations < 400 µg/l (most often < 200 µg/l). The high groundwater level and the presence of contamination inthe upper soil layers makes possible the application of phytoremediation at the site, as part of the contamination is in the rhyzosphere.</p><p>The bench-scale investigation of bioremediation in soil and groundwater contaminated by oil and oil derivatives yielded decreasing concentrations of total hydrocarbons in the soil from 38.2 to 14.6 g/kg and mineral oils from 27.0 to 10.2 g/kg (62%), which can be described by C=C<sub>0</sub>e<sup>-kt</sup>, where the rate constant of hydrocarbon degradation is k=0.0082 day<sup>-1</sup>.</p><p>In water, a large number of carboxylic acids were present, from the oxidation of alkanes (C10-19) and aromatics (benzoic acid, and also benzaldehyde), which indicates a hydrocarbon biooxidation process. The process of dissolving and emulgating the oil is enhanced by recirculating the water: the linear relation between the concentration of hydrocarbons in the liquid and solid phases was found to be dependent on the flow rate: C<sub>water</sub>=(f<sup>*</sup>v+K<sub>0</sub>)C<sub>soil</sub>, where the rinsing coefficient f=1400 s/m, and the diffusion coefficient K<sub>0</sub>=6 x 10<sup>-4</sup>. The process of rinsing the oil and oil derivatives from the soil significantly influences the microbial activity and the degradation of contaminants. With increasing hydrocarbon concentrations, there was generally decreasing bacterial counts and phosphatase activity, and an upper limit for hydrocarbon tolerance was determined. The rinsing process must becontrolled to ensure the mineral oil concentration in water does not exceed 15-35 mg/l, and once the concentration of hydrocarbons becomes less than 400µg/l, passive bioremediation may be left to complete the degradation.</p>
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Isolation and characterization of Cr(VI) tolerant soil bacteria / Izolacija i karakterizacija Cr(VI) tolerantnih zemljišnih bakterijaTamindžija Dragana 23 May 2019 (has links)
<p>In this study, tolerance of soil bacteria to hexavalent chromium (Cr(VI)) was investigated. First, influence of high chromium levels of anthropogenic and geogenic origin on the soil cultivable bacterial community was examined. Next, a number of bacterial strains with high Cr(VI) tolerance were isolated from diverse environmental samples such as soil, sediment, water and waste material. Strains were identified and tested for the level of Cr(VI) tolerance and the ability to<br />reduce toxic Cr(VI) to more innocuous Cr(III). Selected <em>Bacillus cereus</em> group strains were further characterized - their morphological and biochemical characteristics, 16S rRNA and pycA gene sequences, biofilm formation potential and resistance to other heavy metals were determined. Also, more detailed study of their tolerance level and Cr(VI) reduction was conducted. Strain with the highest resistance together with the control chromate sensitive strain were analyzed by STEM EDS for their cellular and endospore Cr content under different conditions. Results indicate Cr(VI) tolerant bacteria are present both in low and high Cr environments. Majority of isolates belonged to the <em> B. cereus </em> group indicating its overall high tolerance to Cr(VI). Certain strains exhibited high tolerance and reduction ability, indicating their possible<br />usefulness in practical bioremediation application. STEM EDS analysis of Cr(VI)-sensitive <em> B. subtilis </em> PY79 strain and Cr(VI)-resistant <em>B. cereus </em> group strain NCr1a revealed significant differences in their response to Cr(VI) and in their Cr cellular and endospore content.</p> / <p>U ovom radu ispitana je tolerantnost zemljišnih bakterija na šestovalentni hrom (Cr(VI)). Prvo, ispitan je uticaj visokog nivoa hroma antropogenog i geogenog porekla na kultivabilnu bakterijsku zajednicu zemljišta. Dalje, izolovani su bakterijski sojevi sa visokom tolerancijom na Cr(VI) iz različitih sredinskih uzoraka kao što su zemljište, sediment, voda i otpadni materijal. Sojevi su identifikovani i određen je nivo njihove Cr(VI) tolerancije i sposobnost redukcije toksičnog Cr(VI) u manje toksični Cr(III). Odabrani sojevi <em>Bacillus cereus </em> grupe su dalje karakterisani – određene su njihove morfološke i biohemijske karakteristike, 16S rDNK i pycA sekvence, potencijal formiranja biofilma i otpornost na druge teške metale. Takođe, sprovedeno je detaljnije ispitivanje njihove tolerancije i redukcije Cr(VI). Soj sa najvišom otpornošću je uporedo sa kontrolnim osetljivim sojem analiziran pomoću STEM EDS na sadržaj hroma u ćelijama I endosporama u različitim uslovima. Rezultati ukazuju da su bakterije tolerantne na Cr(VI) prisutne i u sredinama sa niskim i sa visokim koncentracijama hroma. Većina izolata pripadala je B. cereus grupi što ukazuje na njenu uopšteno visoku otpornost na Cr(VI). Pojedini sojevi su pokazali visoku otpornost i sposobnost redukcije Cr(VI), što ukazuje na mogućnost njihove praktične primene u bioremedijaciji. STEM EDS analiza osetljivog<em> B. subtilis</em> PY79 soja i Cr(VI)- rezistentnog soja <em>B. cereus</em> grupe NCr1a otkrila je značajne razlike u njihovom odgovoru na Cr(VI) i sadržaju Cr u njihovim ćelijama i endosporama.</p>
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Karakterizacija biodegradabilnosti naftnih ugljovodonika u zemljištu i bioremedijacionih procesa u toku tretmana biogomilama i površinskom obradom / Characterisation of the biodegradability of petroleum hydrocarbons in soil and the bioremediation processes during treatment by biopiles and landfarmingMaletić Snežana 01 June 2010 (has links)
<p>U okviru ovog istraživanja ispitani su: (1) Procesi koji se odvijaju prilikom bioremedijacije zemljišta zagađenog naftom i derivatima nafte, koje je bilo izloženo spontanim abiotičkim i biotičkim procesima degradacije u toku 8 godina, tehnikama biogomila i površinske obrade na poluindustrijskoj (pilot) skali uz optimizaciju tehnoloških parametara sa ciljem povećanja efikasnosti i efektivnosti biodegradacije ugljovodonika; (2) Uticaj starenja, koncentracije, biodsotupnosti i strukture zagađujućih materija na procese biodegradacije i biotransformacije u kontrolisanim laboratorijskim uslovima. Tokom dve godine bioremedijacionog tretmana sadržaj mineralnih ulja opao je za 52% (od 27,8 g/kg do 13,2 g/kg) i 53% (od 23,2 g/kg do 10,8 g/kg), dok je sadržaj ukupnih ugljovodonika opao za 43% (od 41,4 g/kg do 23,4 g/kg) i 27% (od 35,3 g/kg do 25,8 g/kg) u biogomili i površinskoj obradi respektivno. Efikasnost uklanjanja mineralnih ulja iz zemljišta u dva posmatrana bioremedijaciona tretmana je praktično ista. Međutim, u pogledu sadržaja ukupnih ugljovodonika u biogomili uklonjeno je dva puta više ukupnih ugljovodonika (gledajući apsolutnu količinu ukupno uklonjenih ugljovodonika). Kinetika biodegradacije mineralnih ulja i ukupnih ugljovodonika u toku tretmana u biogomili u saglasnosti je sa kinetičkim modelima lnC=lnC<sub>0-</sub>kt i lnC=lnC<sub>0-</sub>kt<sup>0,5</sup>. Kinetika biodegradacije mineralnih ulja u toku površinske obrade relativno se dobro može opisati sa dva pomenuta kinetička modela, međutim, znatno bolju korelaciju pokazao je linearni model (C=C<sub>0-</sub>kt) primenjen na prvih 92 i poslednjih 200 dana eksperimenta. Promena sadržaja ukupnih ugljovodonika u toku površinske obrade zagađenog zemljišta relativno je u dobroj korelaciji samo sa kinetičkim modelom lnC=lnC<sub>0-</sub>kt<sup>0,5</sup>. Laboratorijska ispitivanja pokazala su da biodegradabilnost i sudbina ugljovodonika u životnoj sredini jako zavise od tipa, starosti i koncentracije zagađujućih materija. Naime, u slučaju zemljišta sveže kontaminiranog dizel uljem, već pri <br />koncentracijama od 20 mg/g uočen toksičan efekat koji je prevaziđen nakon dve nedelje tretmana kao posledica smenjenja prekomerne koncentracije rastvorenih ugljovodonika biotičkim i abiotičkim putem i adaptacije prisutne mikroflore. U slučaju većih koncentracija ovaj efekat je bio još izraženiji. Kod zemljišta kontaminiranog sirovom naftom isti efekat se javlja tek pri koncentraciji od 35 mg/g, kao posledica toga da sirova nafta sadrži manju količinu lako rastvornih ugljovodonika. Za razliku od sveže kontaminiranog zemljišta, na biodegradaciju starog naftnog zagađanja u zemljištu koncentracija nije imala uticaj, u ovakvom zemljištu respiracija je bila na veoma niskom nivou pri svim ispitivanim koncentracijama, ali ne kao posledica toksičnosti, već kao posledica činjenice da se degradabilni deo zagađujućih materija degradirao tokom procesa starenja, tako da su u zemljištu zaostali visokomolekularni teško rastvorni ugljovodonici (smole, asfaltne komponente i dr.) sekvestrovani u zemljištu. Merenja biodostupnosti ugljovodonika (ekstrakcijom sa Tween80) pokazala su da je u zemljištu sveže kontaminiranom dizel uljem i sirovom naftom i starim naftnim zagađenjem oko 95%, 85% i 40% ugljovodonika biodostupno, respektivno. Koncentracija rezidualne frakcije mineralnih ulja i ukupnih ugljovodonika dobijena nakon 48 dana laboratorijskog tretmana u skoro svim probama je veća od predviđenih, što je posledica bifaznog ponašanja ugljovodonika u zemljištu, gde se jedan deo uklanja biodegradacijom, dok drugi deo difunduje u pore zemljišta i kompleksira se sa zemljišnom organskom materijom. Količina ugljovodonika iz starog naftnog zagađenja zemljišta koja može da pređe u vodenu fazu je mala reda veličine nekoliko mg/l, međutim, u prirodnim uslovima usled spiranja ugljovodonika sa zemljišta kišom, postoji verovatnoća da ovi ugljovodonici dospeju u podzemnu vodu iznad maksimalno dozvoljene koncentracije za vodu za piće (MDK = 10 μg/l) i na taj način degradiraju njen kvalitet. Zbog nemogućnosti daljag uklanjanja zagađenja bioremedijacijom, preostala količina zagađujućih materija koja može dospeti u vodenu fazu bi trebalo da se ukloni nekim drugim remedijacionim tehnikama pre njegovog konačnog bezbednog odlaganja u životnu sredinu.</p> / <p>The aims of this study were to examine: (1) the processes that occur during bioremediation of soil contaminated by oil and oil derivatives, which was exposed to spontaneous abiotic and biotic degradation processes over 8 years, using pilot scale biopiles and landfarming techniques to optimise technological parameters with the aim of increasing the efficiency and effectiveness of hydrocarbons biodegradation. (2) the effect of contaminants weathering, concentration, bioavailability and structure on the biodegradation and biotransformation process under controlled laboratory conditions. Over the two years of bioremediation treatment by biopiles and landfarming, the mineral oil content decreased by 52% (from 27.8 g/kg to 13.2 g/kg) and 53% (from 23.2 g/kg to 10.8 g/kg), and the total hydrocarbon content decreased by 43% (from 41.4 g/kg to 23.4 g/kg) and 27% (from 35.3 g/kg to 25.8 g/kg), respectively. The efficiency of mineral oil removal from soil in these two applied bioremediation treatments was practically the same. However, in terms ofthe absolute amount of total hydrocarbons, twice as many total hydrocarbons were removed in the biopile. The mineral oil and total hydrocarbons biodegradation kinetics in the biopile were in good agreement with the kinetic models lnC = lnC0-kt and lnC = lnC0-kt0.5. The mineral oil biodegradation kinetics during the landfarming treatment is relatively well described with those two kinetic models, however, significantly better correlation is obtained by the linear model (C = C0-kt) applied to the first 92 and last 200 days of the experiment. The change in total hydrocarbons content during the landfarming treatment is in relatively good correlation only with the kinetic model lnC = lnC-kt0.5. The laboratory biodegradation investigation showed that hydrocarbon biodegradability and its fate in the environment strongly depend upon the structure, concentration and weathering of the hydrocarbons. Thus, in the case of diesel contaminated soil, as a consequence of its structure, i.e. the presence in a higher concentration of the soluble and toxic midrange n-alkanes, a toxic effect is detected at a diesel oil concentration of 20 mg/g, although this effect is overcome after two weeks, as a consequence of the decreasing concentration of soluble hydrocarbons in biotic and abiotic processes and microbial adaptation. This effect was more pronounced in the case of the soil withthe highest diesel oil concentration. In crude oil contaminated soil, a toxic effect was observed at a much higher hydrocarbon concentration (35 mg/g) than in the diesel oil contaminated soil, which corresponds to the fact that crude oil contains significantly less soluble hydrocarbon. In contrast to these two freshly contaminated soils, the weathered contaminated soil contaminant concentration did not have an effect on hydrocarbon biodegradation, with biodegradation in this soil actually at a low level at all concentrations, not as a consequence of toxicity, but because the degradable part of the contaminant was already degraded during the weathering process, leaving behind only highly condensed hydrophobic organic contaminants (asphaltenes, resins, etc.) sequestered in the soil. The data obtained for hydrocarbons bioavailability (by Tween80 extraction) showed that the bioavailable hydrocarbon fraction from soils freshly contaminated with diesel oil and crude and weathered oil contamination were approximately 95%, 85% and 40%, respectively. The concentration of residual mineral oil fractions and total hydrocarbons obtained after 48 days of laboratory biodegradability treatment in almost all batches was greater than predicted, as a result of the biphasic behaviour of hydrocarbons in the soil, where some were degraded or lost from the soil and some transformed into the recalcitrant fraction. The amount of hydrocarbons from the weathered soil contamination that can be transferred into the water phase is small, of the order of a few mg/l in magnitude, however, under natural conditions, due to hydrocarbons leaching by rainfall, it is possible that these hydrocarbons infiltrate groundwater above the maximum permissible concentration for drinking water (MAC = 10 μg/l) and thus degrade its quality. As it is not possible to achieve further contamination degradation by bioremediation, the remaining amount of pollutants which can be transferred into the water phase should be removed by some other remediation techniques before its final safe disposal in the environment.</p>
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