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The effect of mineral addition on the pyrolysis products derived from typical Highveld coal / Leon RoetsRoets, Leon January 2014 (has links)
Mineral matter affect various coal properties as well as the yield and composition of products released during thermal processes. This necessitates investigation of the effect of the inherent minerals on the products derived during pyrolysis, as pyrolysis forms the basis of most coal utilisation processes. A real challenge in this research has been quantifying the changes seen and attributing these effects to specific minerals. Thus far it has been deemed impossible to predict product yields based on the mineral composition of the parent coal. Limited research regarding these aspects has been done on South African coal and the characterisation of pyrolysis products in previous studies was usually limited to one product phase. A novel approach was followed in this study and the challenges stated were effectively addressed.
A vitrinite-rich South African coal from the Highveld coal field, was prepared to an undersize of 75 μm and divided into two fractions. HCl/HF acid washing reduced the ash yield from 14.0 wt% d.b. to 2.0 wt% d.b. (proximate analysis). Pyrolysis was carried out with the North-West University (NWU) Fischer Assay setup at 520, 750 and 900°C under N2 atmosphere and atmospheric pressure. The effect of acid washing and the addition of minerals on the derived pyrolysis products were evaluated.
Acid washing led to lower water and tar yields, whilst the gas yields increased, and the char yields were unaffected. The higher gas yield can be related to increased porosity after mineral removal as revealed by Brunauer-Emmett-Teller (BET) CO2 adsorption surface area analysis of the derived chars. Gas chromatography (GC) analyses of the derived pyrolysis gases indicated that the acid washed coal fraction (AW TWD) derived gas contained higher yields of H2, CH4, CO2, C2H4, C2H6, C3H4, C3H6 and C4s when compared to the gas derived from the raw coal fraction (TWD). The CO yield from the TWD coal was higher at all final pyrolysis temperatures. Differences in gas yields were related to increased tar cracking as well as lower hydrogen transfer and de-hydrogenation of the acid washed chars. Analyses of the tar fraction by means of simulated distillation (Simdis), gas chromatography mass spectrometry (GC-MS) –flame ionization detection (–FID) and size exclusion chromatography with ultraviolet (SEC-UV) analyses, indicated that the AW TWD derived tars were more aromatic in nature, containing more heavier boiling point components, which increased with increasing final pyrolysis temperature. The chars were characterised by proximate, ultimate, X-ray diffraction (XRD), X-ray fluorescence (XRF), diffuse reflectance infrared Fourier-transform (DRIFT) and BET CO2 analyses.
Addition of either 5 wt% calcite, dolomite, kaolinite, pyrite or quartz to the acid washed fraction (AW TWD) was done in order to determine the effect of these minerals on the pyrolysis products. These minerals were identified as the most prominent mineral phases in the Highveld coal used in this study, by XRD and quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN) analyses. It was found that mineral activity decreased in the order calcite/dolomite>pyrite>kaolinite>>>quartz. Calcite and dolomite addition led to a decrease in tar yield, whilst the gas yields were increased. Markedly, increased water yields were also observed with the addition of calcite, dolomite and pyrite. Kaolinite addition led to increased tar, char and gas yields at 520°C, whilst the tar yield decreased at 750°C. Pyrite addition led to decreased tar and gas yields. Quartz addition had no noteworthy effect on pyrolysis yields and composition, except for a decrease in char yield at all final pyrolysis temperatures and an increased gas yield at 520°C. Regarding the composition of the pyrolysis products, the various minerals had adverse effects. Calcite and dolomite affected the composition of the gas, tar and char phases most significantly, showing definite catalytic activity. Tar producers should take note as presence of these minerals in the coal feedstock could have a significant effect on the tar yield and composition. Kaolinite and pyrite showed some catalytic activity under specific conditions. Model coal-mineral mixtures confirmed synergism between coal-mineral and mineral-mineral interactions. Although some correlation between the pyrolysis products derived from the model coal-mineral mixtures and that of TWD coal was observed, it was not possible to entirely mimic the behaviour of the coal prior to acid washing.
Linear regression models were developed to predict the gas, tar and char yields (d.m.m.f.) with mineral composition and pyrolysis temperature as variables, resulting in R2 coefficients of 0.837, 0.785 and 0.846, respectively. Models for the prediction of H2, CO, CO2 and CH4 yields with mineral composition and pyrolysis temperature as variables resulting in R2 coefficients of 0.917, 0.702, 0.869 and 0.978, respectively. These models will serve as foundation for future work, and prove that it is feasible to develop models to predict pyrolysis yields based on mineral composition. Extending the study to coals of different rank can make the models universally applicable and deliver a valuable contribution in industry. / MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2015
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Design and Control of Trailer Based Shopping Cart Washing SystemJiacheng, Cai, Chunhong, Yang, Cenan, Chen January 2016 (has links)
The shopping trolley have been frequently used in our daily life. However, the hygiene condition of cart makes people worry a lot, especially the handle brothers. Nowadays, several methods have been proposed to clean the shopping carts but considered uneconomic and inflexible. In this study, we aim to design an integrated cart washing system based on a trailer applied to medium or small supermarket. This system should be more efficient, economic, easily to operate, safer and les water consummation. The integrated cart washing system has three basic functions of washing, disinfection and drying. The system is controlled by PLC program, all steps in the cleaning process are fully automatic insider the trailer and each component are adjustable according to various shopping carts. The system only requires one person to operate and it costs 30 seconds to wash a single cart, able to wash up to 120 cart/hour. Disinfection and drying steps provide high washing quality. Moreover, water-recycling design can save part of wasted water. The modelling and assembly was designed in Autodesk Inventor 2016, the hardware design circuit-writing diagram was performed in AutoCAD, the software design of Programmable logic controller (PLC) was made in STEP 7-Micro/Win. Theoretical calculation and simulation prove the safety and possibility of our system. We concluded that this system might have commercial interests in the market.
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Alcohol-based hand rub in the prevention of diarrhoea and respiratory-tract infection among children in community settings : a systematic reviewSteyn, Joelynn Geraldine Rachelle 04 1900 (has links)
Thesis (MCur)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Annually more than 3.5 million children worldwide, less than five years of age die of
diarrhoea and acute lower respiratory-tract infections. Over the last two decades, the
care of pre-school children outside of their homes has become more common in
most parts of the world and has contributed to an increased risk of respiratory-tract
and gastrointestinal infections in children. Children attending day-care centres are at
an increased risk for diarrhoea and respiratory-tract infections and hands are the
primary vehicle for transmission of infectious diseases. Thus, hand hygiene is
essential for preventing and controlling of infection in the health care and community
settings. Waterless hand sanitizer as an alternative to hand washing was
investigated. Rinse-free hand sanitizer programmes in the community may be
effective, safe and feasible.
The aim of the study was to systematically appraise evidence on the effect of
alcohol-based hand rub in the prevention of diarrhoea and acute respiratory-tract
infection among children aged five years and below in community settings.
The primary outcome of the study was to assess the incidence of respiratory-tract
infection and diarrhea. Diarrhoea is defined by the World Health Organization as the
excretion of three or more loose or liquid stools per day (or more frequent excretion
than is normal for the individual). The secondary outcome was to assess mortality,
admission to hospital and duration of hospital stay.
A comprehensive search for relevant studies was conducted on the following
databases from 1990 to 2014: EMBASE, MEDLINE, CINAHL, Google Scholar and
Cochrane Central Register of Controlled Trials (CENTRAL). We searched the
reference lists of all relevant articles and textbooks for more studies. Unpublished
data previously presented at international and scientific meetings have been
included in the review. Proceedings of international conferences on diarrhoea and
respiratory-tract infection among children were searched for relevant articles. Subject
experts were contacted.
Two reviewers, Joelynn Steyn (JS) and Oswell Khondowe (OK) selected studies
following a two-step study selection process. This review considered all published randomized controlled trials and quasi-experimental designs published from January
1990 to July 2014. The first step was the selection of studies based on titles and
abstracts. Both reviewers selected eligible studies which met the set criteria. During
the second step, both reviewers retrieved the full-text articles of the studies and
assessed the methodological quality of the studies. Four studies were included in
this review. The included studies met most of the quality assessment criteria as
stipulated in the Cochrane risk assessment tool. Two studies were clusterrandomized
controlled trials, one was a block randomized controlled trial and one
was a randomized controlled trial. Disagreements were resolved by discussion and
where a lack of consensus existed, consultation with a third reviewer occurred.
The use of alcohol hand rub as compared to control interventions significantly
reduced the incidence of diarrhoea in children (RR 0.79, 95% CI 0.63 to 0.99).
Statistical heterogeneity was observed among the included studies (I²=69, p=0.04).
However this review found no significant difference in respiratory-tract infections
between intervention groups versus control as observed from the confidence interval
(RR 0.98, 95% CI 0.90 to 1.07, p=0.63). The results should be interpreted with
caution due to the limited number of studies conducted in communities with alcoholbased
hand rub used by caregivers. Due to limited studies in this review, it makes it
difficult to make strong conclusions on findings and to provide sufficient evidence to
guide future research. We therefore recommend that more studies with high quality
methodologies, using randomized controlled trial designs be conducted especially in
poor resourced communities. / AFRIKAANSE OPSOMMING: Meer as 3.5 miljoen kinders jonger as vyf jaar oud sterf jaarliks wêreldwyd as gevolg
van diarree en akute laer respiratoriese lugweginfeksies. Oor die laaste dekades het
die versorging van voorskoolse kinders buite hul tuiste meer algemeen geword in die
meeste dele van die wêreld wat bygedra het tot ’n risiko in die toename van
respiratoriese en spysverteringskanaalinfeksies by kinders. Kinders by
dagsorgsentrums het ’n groter risiko vir diarree en respiratoriese lugweë infeksies
want die oordra van siekte-infeksies word veral deur die hande wat as die primêre
bron daarvan beskou word, gesien. Dus is hand-higiëne noodsaaklik om infeksies in
gesondheidsorg en gemeenskapsentrums te voorkom en te beheer. ’n Waterlose
hande-ontsmettingsmiddel as ’n alternatief om hande te was, is ondersoek. Spoelvrye
hande-ontsmettingsmiddel programme in die gemeenskap mag effektief, veilig
en uitvoerbaar wees.
Die doel van die studie was om sistematies die geslaagdheid van bewyse op die
effek van alkoholgebaseerde hande-smeermiddel in die voorkoming van diarree en
akute lugweginfeksies by kinders 5 jaar en jonger in gemeenskapsentrums te
ondersoek.
Die primêre uitkoms van die studie was om die voorkoms van respiratoriese
lugweginfeksie en diarree te asseseer. Diarree soos gedefinieer deur die WGO is die
uitskeiding van drie of meer los- of waterige stoelgange per dag (of meer gereelde
uitskeiding wat normaal vir die individu is). Die sekondêre uitkoms was om
mortaliteit, toelating tot die hospitaal en duur van hospitaalverblyf te assesseer.
’n Omvattende soektog vir relevante studies was op die volgende databasisse van
2004-2014 uitgevoer: EMBASE, MEDLINE, CINAHL, Google Scholar en Cochrane
Sentrale Register van Beheerde Toetse. Ons het die verwysingslyste van alle
relevante artikels en handboeke vir meer navorsingstudies nagegaan.
Ongepubliseerde data wat voorheen aangebied is by internasionale en
wetenskaplike vergaderings, is ingesluit in die oorsig. Bevindings by internasionale
konferensies oor diarree en lugweginfeksies by kinders was nagegaan in die soektog
na relevante artikels. Onderwerpdeskundiges was gekontak. Die twee navorsers, Joelynn Steyn (JS) en Oswell Khondowe (OK) het studies
geselekteer deur ’n twee-stap studieselekteringsproses te volg. Die oorsig het alle
gepubliseerde, ewekansige gekontroleerde proewe en kwasi-eksperimenteerde
studies oorweeg tussen Januarie 1990 en Julie 2014. Die eerste stap was die
selektering van studies gebaseer op hul titels en opsommings. Beide navorsers het
geskikte studies slegs geselekteer as die studie aan die bepaalde kriteria voldoen
het. Tydens die tweede stap het beide navorsers die volledige artikels geneem van
die studies geselekteer en die gehalte van die metodologie geassesseer. Vierstudies
is in die oorsig ingesluit. Die ingeslote studies het aan die meeste vereistes soos
deur die Cochrane risiko assesseringsinstrument gestipuleer voldoen. Twee studies
was groep-ewekansige gekontroleerde proewe, een was ’n blok ewekansige
gekontroleerde proef en een was ’n ewekansige gekontroleerde proef. Verskille is
opgelos deur bespreking en waar daar onderbreking in konsensus was, het ’n
konsultasie met ’n derde beoordelaar plaasgevind.
Die gebruik van ’n alkohol handreiniger, soos vergelyk met kontrole-intervensies, het
die voorkoms van diarree in kinders beduidend verminder (RR 0.79, 95% CI 0.63 to
0.99). Statistiese heterogeniteit is egter tussen die ingeslote studies waargeneem
(I²=69, p=0.04). Hierdie studie het geen beduidende verskille in lugweg infeksies
tussen die intervensiegroepe teenoor die kontrolegroep gevind nie soos
waargeneem uit die vertroue interval (RR0.98, 95% CI 0.90 to 1.07, p=0.63). Die
resultate moet met omsigtigheid geïnterpreteer word as gevolg van die beperkte
aantal studies wat in gemeenskappe uitgevoer was met alkohol-gebasseerde
handreiniger wat deur versorgers gebruik word. As gevolg van die beperkende
aantal studies in hierdie studie, is dit moeilik om sterk gevolgtrekkings te maak op
bevindinge en om voldoende bewyse te gee om toekomstige navorsing te rig. Ons
beveel dus aan dat meer studies met hoë kwaliteit metodologie en wat ewekansige
gekontroleerde proef-ontwerpe gebruik, uitgevoer word, veral in swak-toegeruste
gemeenskappe.
(RR0.98, 95% CI 0.90 to 1.07, p=0.63). Die resultate moet met omsigtigheid geïnterpreteer
word as gevolg van die beperkte aantal studies wat gedoen is in gemeenskappe met
alkohol-
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Removal of heavy metals from CRUD and slime dam material using soil washing and bioremediationShumba, Trust 12 1900 (has links)
Thesis (MScEng (Process Engineering))--Stellenbosch University, 2008. / A substance called CRUD (Chalk River Unidentified Deposit) was deposited together
with gold tailings to the East Paydam tailings dam. Previous research conducted on
the material has shown that the crud leaches Mn and Ni at concentrations that are
above their acceptable risks limits as well as Zn which leaches at concentration
slightly below its acceptable limits thereby posing an environmental risk. The main
objective of the research was to test the hypothesis stating that soil washing in series
with bioremediation can be used to remove the heavy metals from the material from
the East Paydam tailings dam.
Various laboratory and pilot scale tests were conducted to investigate critical soil
washing and bioremediation parameters and their respective influence on the
treatment process. Laboratory work involved column tests and batch tests. These tests
were crucial in determining the critical parameters for the pilot scale tests such as the
selection of the suitable lixiviant from the four that were investigated. The optimal
concentration of the lixiviant was also determined together with the optimum soil:
liquid ratio. These parameters were employed in the pilot scale tests. Pilot scale tests
involved soil washing in series with bioremediation. The bacterial growth over the
bioremediation period was also determined. Precipitation of the heavy metals from
leachate was investigated by varying the pH and temperature.
Results showed that the soil from the East Paydam can effectively be treated by soil
washing in series with bioremediation. Oxalic acid was selected for soil washing of
the payable slimes at a concentration of 0.001M. However, material that contains high
amount of CRUD (deeper down the slime dam) required the relatively concentrated
0.1M oxalic acid and mechanical agitation. Bioremediation was determined to
increase the amount of heavy metals that was leached from the material from the East
Paydam slimes dam. Precipitation of the heavy metals at a pH of 12 achieved up to
98% removal of heavy metals from leachate.
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Handwashing practice in Hong Kong during SARS (2003) and bird flu (2004)Ng, Yee-ting, Omi., 吳綺婷. January 2008 (has links)
published_or_final_version / Public Health / Master / Master of Public Health
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Estudo do comportamento dinâmico e do fenômeno de deslocamento em lavadoras de roupas de eixo vertical / Study of the dynamic behavior and walking phenomenon of a vertical axis washing machineBarcha, Wladimir Alex Magalhães 28 September 2004 (has links)
Este trabalho apresenta e compara alguns meios para o estudo do comportamento dinâmico de uma lavadora de roupas de eixo vertical durante o processo de extração de água das roupas, também conhecido como centrifugação. Os três métodos utilizados para estudar o comportamento dinâmico de uma lavadora de roupas de eixo vertical foram: analítico, experimental e simulação através de multicorpos. O interesse nesta etapa é devido ao fato dos problemas de vibração de uma lavadora ocorrerem principalmente durante a centrifugação. A modelagem de uma lavadora de roupas durante a etapa de centrifugação permite a obtenção de seu comportamento dinâmico bem como de suas principais características. Um outro tópico estudado neste trabalho foi o fenômeno de deslocamento da lavadora, um dos principais motivos de reclamação dos usuários de lavadoras de roupa automáticas. / This work presents and compares some ways to study the dynamic behavior of a vertical axis washing machine during the water extraction process, also called spinning stage. The three methodologies used to study the dynamic behavior of a vertical axis washing machine area: analytical, experimental and simulation using Multi Body System. The interest in this stage is due to the fact that the main vibration problems of an automatic washing machine occur in the spinning cycle. Since the unbalance force that causes the vibration problems is centrifugal in nature, this makes intuitive sense as the rotational speed of the basket is the largest during the spin extraction cycle. Thus, modeling the washing machine during the spinning cycle allow us to get its dynamic behavior as well as the main characteristics of this behavior. Another topic studied in this work was the walking phenomenon, the main complaint of the users.
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A community randomised controlled trial evaluating a home-based environmental intervention package of improved stoves, solar water disinfection and kitchen sinks in rural Peru: Rationale, trial design and baseline findingsHartinger, S.M., Lanata, Claudio F., Hattendorf, J., Gil, I., Verastegui, H., Ochoa, T., Mäusezahl, D. 24 March 2015 (has links)
clanata@iin.sld.pe / Introduction: Pneumonia and diarrhoea are leading causes of death in children. There is a need to develop effective interventions. Objective: We present the design and baseline findings of a community-randomised controlled trial in rural Peru to evaluate the health impact of an Integrated Home-based Intervention Package in children aged 6 to 35 months. Methods: We randomised 51 communities. The intervention was developed through a community-participatory approach prior to the trial. They comprised the construction of improved stoves and kitchen sinks, the promotion of hand washing, and solar drinking water disinfection (SODIS). To reduce the potential impact of non-blinding bias, a psychomotor stimulation intervention was implemented in the control arm. The baseline survey included anthropometric and socio-economic characteristics. In a sub-sample we determined the level of faecal contamination of drinking water, hands and kitchen utensils and the prevalence of diarrhoegenic Escherichia coli in stool specimen. Results: We enrolled 534 children. At baseline all households used open fires and 77% had access to piped water supplies. E. coli was found in drinking water in 68% and 64% of the intervention and control households. Diarrhoegenic E. coli strains were isolated from 45/139 stool samples. The proportion of stunted children was 54%. Conclusions: Randomization resulted in comparable study arms. Recently, several critical reviews raised major concerns on the reliability of open health intervention trials, because of uncertain sustainability and non-blinding bias. In this regard, the presented trial featuring objective outcome measures, a simultaneous intervention in the control communities and a 12- month follow up period will provide valuable evidence. / This study received financial support of the UBS Optimus
Foundation, through a grant given to the IIN and Swiss TPH.
The sponsors had no role in the design and conduct of the
study; collection, management, analysis, and interpretation of
the data; or preparation, review, or approval of the
manuscript. / Revisión por pares
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Optimering av pigmenttryck / Optimization of pigment printCENTRÉN, REBECCA, PERSSON, JESSICA January 2010 (has links)
En pigmentpasta består av ett antal olika kemikalier som alla bidrar med en specifik egenskap. Färgpigment, bindemedel och förtjockare är de tre komponenter som måste finnas i tryckpastan. Nackdelar med pigmenttryck är att trycket kan få dålig färg- och gnidhärdighet eftersom pigmentet inte tas upp av fibern utan binder till substratet genom ett bindemedel. Gnid- och tvätthärdighet bestäms nästan helt av vilket bindemedel som används. Vid pigmentryckning är bindemedlen som används oftast vattenbaserade syntetiska emulsionspolymerer.Syftet med detta examensarbete var att undersöka hur man kan optimera pigmenttryck och dess färg- och gnidhärdighet. En del av arbetet bestod av en laborationsdel där målet var att utvärdera hur olika fixeringsparametrar och olika bindemedel i en pigmentpasta kan påverka slutresultatet.I experimentet användes fyra olika bindemedel; Jaypol B2, Jaypol B3, Tubifast AS 40 och Tubifast ABN 10. För varje bindemedel gjordes två olika pastor. En pasta med 200 g/kg bindemedel och en pasta med 300 g/kg bindemedel. På proverna utfördes tester för gnidhärdighet och färghärdighet mot tvätt för att kunna utvärdera de olika bindemedlen. Testerna visade ett klart samband mellan en ökad koncentration av bindemedel i tryckpastan och en bättre färg- och gnidhärdighet. För att få bra egenskaper på ett pigmenttryck är det viktigt att det fixeras ordentligt. Om trycket inte fixeras tillräckligt kan inte bindemedlet binda fast pigmentet till textilen vilket ger dåliga härdigheter. Testerna visade att det inte finns någon optimal fixeringstid eller temperatur som gäller för alla tryck. Varje enskilt tryck kräver speciella förhållanden för att få så optimala egenskaper som möjligt. / <p>A pigment paste consists of a number of different chemicals that all contribute with a specific property. Color pigment, binder and thickener are the three components that must exist in the printing paste. The disadvantage of pigment printing is that the print may have poor color and crock fastness because the pigment is binding to the substrate by a binder and is not being absorbed by the fiber. Wash and crock fastness are determined almost entirely by which binder that are used. The binders that are used in pigment printing are usually water-based synthetic emulsion polymers. The purpose of this study was to examine how to optimize a pigment print and its color and crock fastness. The work included a laboratory test where the focus was to evaluate how different fixation parameters and different binders in a pigment paste can affect the final result. In the experiment four different binders were used; Jaypol B2, Jaypol B3, Tubifast AS 40, Tubifast ABN 10. For each binder two different pastes were made. One paste with 200 g/kg binder and one paste with 300 g/kg binder. Tests were made on the samples for crock fastness and color fastness to washing with the purpose to evaluate the various binders. The tests showed a clear correlation between an increased concentration of binder in the printing paste and a better color and crock fastness. In order to obtain good properties of a pigment print it is vital that the fixation is done properly. If the print is not adequately fixated the binder cannot attach the pigment to the fabric, resulting in poor fastness. The tests showed that there is no optimal fixation time or temperature for all prints. Each individual print requires special settings to obtain as optimal properties as possible</p><p>Program: Textilingenjörsutbildningen</p>
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Avalia??o de estrat?gias para remedia??o de solo contaminado por chumbo e b?rio provenientes de res?duos de perfura??o de po?o de prospec??o de petr?leo / Evaluation of strategies for remediation of soil contaminated by lead and barium, from well drilling oil prospecting wasteANDRADE, Andr? Fern?o Martins de 31 August 2010 (has links)
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Previous issue date: 2010-08-31 / UNIFOA / This study begun with a field survey in a one hectare area of petroleum drill waste (rocks and mud came from perforation) in Santa Maria do Oeste, in Paran? state, Brazil. It was verified different levels of metal contamination in the area, according to the surface position and with depth, with barium and lead over the investigation standard according to legislation. The highest level contaminated material was collected and used in a laboratory and greenhouse experiment at the campus of the Universidade Federal Rural do Rio de Janeiro, initiated on December, 2007, and completed on June, 2010. The objective was to evaluate the efficiency of remediation by washing contaminated soil (in situ and ex-situ) as well as phytoremediation. The waste washing ex-situ was simulated such as the contaminant would be removed from soil using a rotating device, with soil mixed with an ethylenediaminetetraacetic acid (EDTA) solution in the proportion of 1:10. Removal of lead and calcium increased proportionally to concentration of extractor (from 100 to 1500 mmol L-1). Removal of barium increased considerably above 600 mmol L-1. Iron and manganese showed little influence by different concentration of extractor. The soil washing in-situ was simulated by addition of two solutions of EDTA, with concentration of 150 and 300 mmol L-1, and the control (water). The material was incubated in plastic columns, for three weeks, after that volumes of 100 mL of deionized water were added weekly for three weeks, and after that samples were taken daily up to a total of ten. The leached was collected and the barium and lead content were analyzed, also other metals that could interfere with the extraction. The fractions (exchangeable, iron bound, organic matter bound, and residual) that metals were associates in the waste, before and after washing, were also determined. It was found, in the higher EDTA concentration, a small extraction of barium, while lead had about 20% of the total in soil extracted. The phytoremediation was carry on with two species, Brachiaria decumbens cv. Basilisk, an herbaceous plant, and Cordia africana, an arboreal. The plants growing up in vases with 4 kg of substratum were irrigated with deionized water and Hoagland nutrient solution (25% of ionic power). Two treatments were used in the phytoextraction induced with EDTA, in the concentration of 6 mmol L-1 (with one single application, and 3 dosages of 2 mmol L-1), plus the control. After 150 days for Brachiaria and 270 days for Cordia, the plants were collected, and analyzed (root and shoots) for heavy metal content. EDTA was effective to induce metal absorption, except for barium and calcium, where lead concentrated in the roots and barium in leaves (with highest concentration for EDTA applied in one dose). For Cordia, barium distributed equally in the plant sections, and lead concentrated in the roots. / Este trabalho iniciou-se com levantamento de campo na ?rea de despejo do res?duo de perfura??o de po?o de prospec??o de petr?leo (cascalhos e fluidos da broca) em Santa Maria do Oeste, Estado do Paran?, que possui ?rea aproximada de um hectare. Constatou-se que a ?rea apresentava diferentes n?veis de contamina??o de metais, estando, de acordo com sua posi??o no plano e em profundidade, com n?veis de b?rio e o chumbo na faixa de investiga??o, conforme norma legal. O material com maior n?vel de contamina??o foi coletado e utilizado em experimento de laborat?rio e casa de vegeta??o no campus da Universidade Federal Rural do Rio de Janeiro, a partir do m?s de dezembro de 2007 e finalizado em junho de 2010. Objetivou-se avaliar a efici?ncia da remedia??o atrav?s da lavagem do solo contaminado (in situ e ex-situ) bem como da sua fitorremedia??o. A lavagem do res?duo ex-situ foi simulada como aquela em que o contaminante seria removido do solo em um reator rotativo, onde o solo seria misturado em batelada a solu??o de EDTA na propor??o 1:10. A remo??o de chumbo e c?lcio aumentou com o aumento da concentra??o do extrator (de 100 a 1500 mmol L-1). A remo??o do b?rio aumentou consideravelmente acima de 600 mmol L-1; ferro e mangan?s foram pouco influenciados pelas diferentes concentra??es. A lavagem do solo in situ foi feita com adi??o de duas solu??es de ?cido etilenodiamino tetra-ac?tico diss?dico (Na2EDTA), de concentra??es 150 e 300 mol L-1, al?m da testemunha (?gua), em colunas est?ticas que, ap?s um per?odo de tr?s semanas de incuba??o, receberam 100 mL de ?gua deionizada a cada semana por tr?s semanas e, depois, uma coleta por dia at? perfazer 10 coletas. Os lixiviados foram coletados e analisados os teores dos contaminantes b?rio e chumbo, al?m de outros metais interferentes com a extra??o. Determinou-se, ainda, as diversas fra??es (troc?vel, ligada a ?xidos, ligada ? mat?ria org?nica e residual) em que esses metais se encontravam no res?duo antes e ap?s a lavagem. Foi verificada, na maior concentra??o de EDTA, extra??o insignificante de b?rio, enquanto o chumbo teve extra?do cerca de 20% do seu total no solo. A fitorremedia??o deu-se por meio do uso de duas esp?cies, uma herb?cea (Brachiaria decumbens cv. Basilisk) e outra lenhosa (Cordia africana). As plantas se desenvolveram em vasos com 4 kg de substrato, recebendo fertirriga??o (solu??o de Hoagland a 25% de for?a i?nica). Foram usados dois tratamentos na fitoextra??o induzida com EDTA, na concentra??o de 6 mmol L-1 em duas formas de aplica??o (3 aplica??es de 2 mmol.L-1 e uma de 6 mmol L-1) e a testemunha. Ap?s per?odo de desenvolvimento de 150 dias para a braqui?ria e de 270 dias para a c?rdia, as plantas foram coletadas tendo suas ra?zes e a parte a?rea analisada quanto ao conte?do de metais. Na braqui?ria, o EDTA foi efetivo na indu??o da absor??o dos metais com exce??o do b?rio e do c?lcio, tendo o chumbo se concentrado nas ra?zes e o b?rio nas folhas (com maior concentra??o no tratamento de aplica??o ?nica de EDTA). Na c?rdia, o b?rio distribuiu-se igualmente entre as partes analisadas e o chumbo se concentrou nas ra?zes.
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Efeito da aplica??o de res?duo de perfura??o de po?o de petr?leo no desenvolvimento de cevada (Hordeum vulgare L.) / Effect of application of drill cuttings from oil well in the development of barley (Hordeum vulgare L.)CARVALHO, Michel Miranda de 26 April 2013 (has links)
CNPq / Faced with the need to implement a sustainable development, and seeking solutions for protecting the environment, the management of residues has undergone marked changes. Companies are increasingly involved in the optimization of residues produced in their production processes. The oil industry participates in this search by funding research and development of environmentally sound technologies. This study aimed to evaluate the development of barley plants (Hordeum vulgare L.) in soils incubated with drill waste from oil well treated by washing to eliminate the influence of sodium. Two residues generated during drilling of the well 7-SMC-50D-AL were selected to be used in two assays: one in pots planted with barley, and one with leaching columns. For the pots testing the residues were washed with water, using a ratio of 1:5, aiming to reduce the effects of the sodium. Thus, the washing treatment defined two other conditions: residue washed and unwashed. The quantity of residue added to the soil was defined in order to obtain the barium concentrations of 300 mg kg-1, 600 mg kg-1 and 1200 mg kg-1. The soil moisture was maintained at 70% of field capacity. The experimental units were kept incubated for 30 days, and covered with plastic bags to prevent water loss by evaporation. The plants sowing was made using 10 seeds in each pot, and after the thinning with 30 days there was left 4 plants per pot. After the harvesting, the plants were separated into root, shoot and grain; and it was evaluated the absorption of the elements barium, iron, manganese, calcium, sodium, zinc and potassium. The results showed that the residues of the centrifugal and the dryer promoted an increased production of plant dry matter, especially in the treatment with the residue washing. For the test columns, there was no washing of the residues. The same doses were tested with two conditions of humidity (70% of field capacity and reduced condition, simulating the presence of a ground water table). During the incubation the pH and the redox potential (Eh) were monitored until, in the reduction condition, values close to ? 200 mV were obtained, and then, waiting for 30 days to ensure the occurrence of the reduction reactions. After that, the leaching test proceeded, simulating rainfall and collecting the extract leachate to evaluate the barium content. The geochemical fractionation of barium was done using a modification of the BCR method. The fractionation results showed that the reduction condition provided greater availability of barium, increasing the bioavailable fraction for both cuttings. In the leaching test, there was an increase in barium level in the reduction condition, due to the reduction of sulfate to sulfide. / Diante da necessidade de implementar o desenvolvimento sustent?vel, buscando solu??es para a prote??o do meio ambiente, a gest?o de res?duos tem passado por mudan?as marcantes. As empresas est?o cada vez mais envolvidas na otimiza??o de res?duos produzidos em seus processos produtivos. A ind?stria petrol?fera participa dessa busca por solu??es atrav?s do financiamento de pesquisas e do desenvolvimento de tecnologias ambientalmente seguras. Este trabalho teve como objetivo avaliar o desenvolvimento de plantas de cevada (Hordeum vulgare L.) em solos incubados com res?duos de perfura??o de po?o de petr?leo tratados com lavagem para eliminar a influ?ncia do s?dio. Foram selecionados dois res?duos gerados durante a perfura??o do Po?o7-SMC-50D-AL para serem utilizados em dois ensaios: um com vasos cultivados com cevada e outro com colunas de lixivia??o. Para o ensaio com vasos foi feita a lavagem dos res?duos em ?gua, na propor??o 1:5, visando diminuir os efeitos do s?dio. Dessa forma, o tratamento de lavagem definiu duas condi??es: res?duo lavado e res?duo n?o lavado. A quantidade de res?duo adicionada ao solo foi definida de modo a atingir as concentra??es de b?rio de 300 mg kg-1, 600 mg kg-1 e 1200 mg kg-1. A umidade do solo foi mantida a 70% da capacidade de campo. As unidades experimentais permaneceram incubadas por 30 dias, cobertas com sacos pl?sticos para evitar a perda de ?gua por evapora??o. Em seguida foi feita a semeadura, utilizando 10 sementes em cada vaso, e com o desbaste ap?s 30 dias restaram apenas 4 plantas por vaso. Ap?s a coleta as plantas foram separadas em raiz, parte a?rea e gr?os e foi avaliada a absor??o dos elementos b?rio, ferro, mangan?s, c?lcio, s?dio, zinco e pot?ssio. Os resultados obtidos demonstraram que os res?duos do secador e da centr?fuga promoveram aumento da produ??o de mat?ria seca pelas plantas, principalmente no tratamento lavado. Para o ensaio com colunas n?o houve lavagem dos res?duos. Foram testadas as mesmas doses em duas condi??es de umidade (70% da capacidade de campo e ambiente reduzido com presen?a de l?mina de ?gua). Durante a incuba??o foi feito o monitoramento de pH e potencial redox (Eh) at? que, na condi??o de redu??o, fossem atingidos valores pr?ximos de -200 mV, aguardando por 30 dias para assegurar a ocorr?ncia das rea??es de redu??o. Em seguida foi feito o ensaio de lixivia??o, simulando uma precipita??o e coletando o extrato lixiviado para avalia??o quanto ao teor de b?rio. Foi feito o fracionamento geoqu?mico do elemento b?rio utilizando-se o m?todo BCR com algumas modifica??es. Os resultados mostraram que no fracionamento as fra??es biodispon?vel para ambos os res?duos na condi??o de redu??o proporcionou uma maior disponibilidade do b?rio. Na lixivia??o houve um aumento dos teores de b?rio na condi??o de redu??o proporcionado pela redu??o de sulfato a sulfeto.
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