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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Bygg- och rivningsavfall- Hanteras kakel och klinker på rätt sätt? / Construction- and demolition wasteAre tile and clinker handled correctly?

Läckgren, Robin, Osama, Yesen January 2014 (has links)
Inom byggbranschen omsätts stora mängder byggavfall. Avfallet är svårt att hantera för att det består av så stora mängder. Restavfall som kommer från en byggarbetsplats källsorteras. Avfall från byggnation och rivning innehåller många olika typer av miljöfarliga ämnen, vilket förorsakar miljöföroreningar. Farliga ämnen riskerar att läcka ut i marken och ut i naturen. Branschen har funderat på om kakel och klinkers verkligen deponeras på rätt sätt idag från byggavfall och rivning. Syftet med arbetet var att undersöka om kakel och klinkers innehåller metaller som kan vara miljöfarliga. Halterna i ytskikten uppmättes och genom att utföra laktester kunde vi analysera avgivningen från materialen i olika miljöer. Det visade sig att kakel och klinker innehåller höga halter av metaller som kan läcka ut till omgivningen vid lågt pH-värde. Slutsatsen från laktesterna är att om kakel och klinker hanteras på rätt sätt i neutral eller basisk miljö är det inte miljöfarligt, eftersom samtliga utlakningsvärden vid pH åtta till tio låg inom gränserna. Men vi ser en fara om kakel och klinker hamnar i en sur miljö som har ett lågt pH runt fem till sex. Då är kakel och klinker inte inert avfall och skall alltså inte hanteras som det. Detta gör att kakel och klinker inte bör användas som till exempel fyllnadsmassor, utan att det bör deponeras som det görs idag. Arbetet bygger till stor del på diskussioner och samtal med Structor i Örebro och MTM på Örebro Universitet. / The construction industry deals with large quantities of construction waste. The waste is difficult to manage because of large amounts. Residual waste that comes from a construction site is recycled. Waste from construction and demolition includes many different types of pollutants causing environmental pollution. Hazardous substances likely to leach into the soil and into the wild. Structor have been thinking about if tile and clinkers tiles really are deposited in the right way today from construction waste and demolition. The purpose of this work is to investigate whether tile and clinker contains metals that can be harmful to the environment. The contents in the surface layers were measured and by performing leaching tests, we could analyze the leakage from materials in different surroundings. The samples proved that tile and clinker have high level of metals in the materials that can be given off to the environment at low pH. The conclusion from the leaching tests is that if the tiles are handled properly in the neutral or alkaline environment, it is not harmful to the environment because all results of leaching tests at pH values between eight and ten were within limits. But we see a danger if tiles end up in an acidic environment that has a low pH of around five to six. Then the tiles are not inert waste and therefore should not be handled like that. Tiles should thus not be used to such as aggregate, but it should be deposited as is done today. The work is largely based on discussions and conversations with Structor in Örebro and MTM at Örebro University.
2

IMPACTS OF ROAD DE-ICING SALTS ON MANGANESE TRANSPORT TO GROUNDWATER IN ROADSIDE SOILS

Wen, Yingrong January 2012 (has links)
Manganese (Mn) is an important element in soil, it occur natural in minerals and precipitated as Mn-oxides. Several factors could decide the solubility and mobility of Mn in soil water. In this study, the impact of road de-icing salts (NaCl) on manganese mobilization and transport to groundwater in roadside soils has been investigated by leaching tests. Generally, in the salt solution leachates, the water-soluble concentrations of Mn tended to increase with elevated salt concentrations, suggesting that ion exchange mainly affected the mobilization. The process was also attributed to the complexion with Cl. Associated with exchangeable concentration of Mn and soil properties such as pH and acidity, the mobilizations of Mn varied. Mn-oxides can dissolve when reduced condition exists, therefore the oxalate extractable Mn was extracted to estimate the change of redox potential condition in roadside soils. The redox potential of soil samples is higher in general. Redox condition has little effect on the Mn solubility and mobility in this research. Although groundwater samples indicated that only a few periods and sites were under threaten of elevated concentrations of manganese, there is still great risk of transport of high water-soluble concentrations of Mn in roadside soils to groundwater, especially the areas exposed to de-icing salts. In addition, lower value of Mn concentrations in groundwater for considering good drinking water quality for the well-being of children should be paid more attention to.
3

Assessing the suitability of using the by-product Petrit-E from steel production as agricultural fertilizer

Galyas, Eva January 2022 (has links)
Due to the growing population, waste generation and food supply industries need to move towards a circular economy and take advantage of by-products. Metallurgical slag is a main by-product during steel production which contains several valuable minerals and can be used for several further applications, including water purification and agriculture. This thesis has a focus on the issue(s) that need to be assessed to be able to determine the suitability of Petrit-E steel slag from Höganäs AB for agricultural use after it has been used for water purification. This slag by-product has been tested and it was successful to purify wastewater from phosphorus (P). The use as a fertilizer is most promising because it contains the major fertilizer substances and it contains P which is a limited resource. Calculations were done for the mean value and standard deviation of the substances for three years and after for Cr (chromium) and Ni (nickel) contents in Petrit-E because these two metals that are present in the slag and are regulated in the regulation for limit values. The total contents of Cr and  Ni were higher than the limit values so there are these two metals that need to be assessed further. Since Petrit-E is not a sludge and not a virgin material either, it requires other methods such as leaching tests by accredited laboratories. These tests are suitable for risk assessments and to estimate the amounts of metal availability for leaching. Leaching tests based on the site specific (local) chemical and physical processes and characteristics in the soil are necessary to estimate the suitability of Petrit-E.
4

Methodology for evaluation of hazards from solid waste and landfill-generated leachate

Svensson, Britt-Marie January 2008 (has links)
A methodology based on an analytical protocol for evaluation of hazards from landfill leachate and solid waste is described. A dynamic analytical protocol, the LAQUA protocol, including measurements of inorganic and water-quality parameters, polar and non-polar organic marker compounds, and toxicity, was constructed. An acute toxicity test, using the brackish water crustacean Artemia salina as test organism, was developed. The methodology was applied to authentic problems such as investigation of different treatment techniques for landfill leachate, evaluation of leaching tests and characterization of solid wastes, and an investigation of a filter material aimed for leachate treatment. Investigated treatment methods comprised in all cases pre-treatment by aeration combined with sedimentation, followed by one of: bioremediation, ozonation, chemical oxidation by Fenton’s reagent, or geo-bed filters. Evaluated filter materials were mixtures of natural or residual waste products. A combination of pre-treatment followed by a geo-bed filter containing a mixture of peat and carbon-containing ash gave an efficient simultaneous removal of metals and organic pollutants. The performance of two leaching tests for characterization of solid waste, the up-flow percolation test (SIS-CEN/TS 14405:2004) and the batch test (SS-EN 12457 -3), was investigated. Solid waste materials (sludge from street gutters and fragmented metallic waste) were characterized using leaching tests and the hazards of the materials were evaluated in the eluate, obtained at specific liquid-to-solid ratios (L/S). The L/S 2 and L/S 10 values were compared with limit values included in the waste acceptance criteria (WAC). The analyses were extended towards specific organic compounds, such as individual phenolic compounds and polychlorinated biphenyls (PCB). Organic compounds were found in eluates from both types of tests, showing the possibility to use these methods to evaluate the leaching of such compounds from waste materials. The use of authentic leachate as leachant, leads to increased concentrations of heavy metals in the eluate, compared to the prescribed use of demineralised water as leachant. Generally good agreement was found between the results of the two leaching methods. A strategy based on batch tests is described for investigation of a filter material for leachate treatment. Batch tests gave suitable information about the leaching from new and used material, and showed high removal efficiencies of metals and non-polar organic compounds. However, for investigation of removal of polar organic markers (e.g. phenolic compounds) a batch test is not sufficient and should be supplemented by a column test. / Avfall har alltid uppkommit i alla samhällen i alla tider. Det vanligaste sättet att hand om det har varit att samla avfallet i soptippar (deponier) på mark som ansetts obrukbar, t.ex. i sankmarker utanför bebyggelsen. I takt med ökad konsumtion och produktion har också mängderna avfall ökat. Anledningen till att avfall och avfallshantering kommit alltmer i fokus i miljödebatter under de senaste decennierna, är inte bara de stora mängderna avfall på de många och stora sopbergen runt om i världen. Deponierna släpper också ifrån sig miljöfarliga ämnen från de alltmer komplexa produkter som blivit lagda i deponin. Dessa kommer att fortsätta att läcka ut länge efter det att deponeringen på soptippen slutat, och skapa problem för människor och miljö i flera generationer. Som en konsekvens av internationella beslut bl.a. Agenda 21 (FNs miljökonferens i Rio) och EUs lagstiftning om avfallshantering som Sverige har tagit in i sin lagstiftning, kommer bl.a. antalet soptippar att minska. Efter den 31 december 2008 beräknas endast ett 90-tal deponier för kommunalt avfall att vara i drift i Sverige. Lagstiftningen beskriver en avfalls hierarki där deponering är den sämsta och absolut sista åtgärden som får göras bara när inget av de andra alternativen kan uppfyllas. Det ställs stora krav på de soptippar som är godkända enligt den nuvarande lagstiftningen. Olika typer av deponier ska finnas för olika slag av avfall. En deponi för farligt avfall har bättre skydd mot läckage både under och över tippen än en tipp för icke-farligt avfall. För att ha kontroll på vilket avfall som läggs på deponin och därmed kunna behandla det på korrekt sätt, måste avfallet beskrivas och klassas innan det skickas för deponering. Karakteriseringen görs bl.a. med hjälp av lakningstester. Syftet med denna avhandling har varit att utarbeta en metodik för at utvärdera miljöfarliga ämnen som kommer från avfall och lakvatten från soptippar. Den inledande forskningen utgjordes av ett projekt kallat Laqua, finansierat av EU-kommissionens program för samarbete inom Östersjöregionen, SweBaltcop. Projektets uppgift var att främja utveckling av ekologiskt och ekonomiskt hållbara reningsmetoder för lakvatten. Lakvattnet bildas främst av nederbörd som faller över deponin. Det vatten som kommer in i soptippen tar med sig många av de ämnen som finns i tippen när det rinner ut. Dessa ämnen kan komma från sådant som har deponerats eller bildas när avfallet bryts ner. Lakvattnet samlas upp och renas på något sätt innan det släpps ut till ett naturligt vattendrag. En vanlig metod att behandla lakvatten är att pumpa det till det kommunala avloppsreningsverket och rena det tillsammans med avloppsvatten. Men detta är ingen optimal lösning eftersom lakvatten innehåller andra föroreningar än avloppsvatten, t ex salter, tungmetaller och svårnedbrytbara organiska föreningar. Avloppsreningsverken är konstruerade för att rena avloppsvatten och lakvattnets föroreningar kan störa reningsprocessen. Framför allt kan de känsliga mikroorganismerna i det biologiska reningssteget påverkas negativt. Slammet som bildas vid reningsprocessen kommer att koncentrera många av de oönskade föroreningarna som härstammar från deponin. Slammet är egentligen ett utmärkt gödselmedel för jordbruket, men på grund av att slammet är förorenat av tungmetaller och svårnedbrytbara organiska ämnen kan inte slammet användas. Slammet blir då ett avfall som kommunen inte kan bli av med utan stora kostnader. Många kommuner har därför valt en separat rening av lakvattnet. Val av reningsteknik är beroende av flera faktorer, som volymerna lakvatten som uppkommer, innehållet av de olika miljöfarliga ämnena, vart det renande vattnet ska släppas ut och utrymme för att bygga en reningsanläggning. För att utvärdera olika tekniker för rening av lakvatten, byggdes en försöksanläggning på soptippen i Kristianstad. För att kunna utvärdera en reningsmetod måste bestämningar av koncentrationer av olika ämnen (analyser) göras. På grund av den ökande oron för organiska miljögifter som PCB och fenoler, skulle reningsteknikerna utvärderas med fokus sådana eller liknande ämnen. Analyser av organiska ämnen är komplicerade och tidskrävande, och det är inte möjligt att analysera alla ämnen. I många undersökningar används endast generella parametrar för att uppskatta innehållet av organiska ämnen, men dessa metoder ger ofta inte tillräcklig information om det egentliga innehållet i lakvattnet. Därför utarbetades ett utvärderings protokoll, LAQUA protokollet (artikel I) för bestämning av organiska miljögifter i olika förorenade vatten. Detta protokoll innehåller förutom analyser för organiska miljögifter som PCB och fenoler och en akut toxicitetstest, även standardiserade rutinanalyser av metaller och vattenkemiska parametrar. Eftersom separat analys av alla organiska ämnen inte nödvändig för att bedöma olika reningsmetoder för lakvatten, innehåller protokollet ett antal markörer för polära, respektive opolära organiska föreningar. Den biologiska giftighetstesten som utvecklades (artikel III) och ingår i protokollet är ett s.k. akut toxicitetstest, dvs. organismen påverkas direkt av höga halter av föroreningar. I testen används det lilla saltvattentåliga kräftdjuret Artemia salina, som säljs som föda åt akvariefiskar. En bestämd volym med ett antal Artemia larver läggs i små brunnar med olika koncentrationer av lakvatten under 24 timmar. Sedan jämförs vid vilken inblandning av lakvatten som hälften av kräftdjuren har fått rörelsestörningar. Resultaten på tester med obehandlat lakvatten, respektive behandlat med olika reningstekniker jämförs, och på det viset kan effektiviteten på reningsmetoder bedömas gentemot en vattenlevande organism. Utvärderingen av försöksanläggningen (artikel II) visade att vid förbehandlingen, bestående av luftning och sedimentering, togs mycket av föroreningarna bort, och det rekommenderas att ett sådan reningssteg alltid bör finnas vid en reningsanläggning för lakvatten. De kemiska behandlingsmetoderna med ozon och Fentons reagens (tvåvärt järn och väteperoxid) var effektiva på att ta bort de organiska miljögifterna, men även de mer kostnadseffektiva filterbäddarna visade sig fungera bra. Den goda erfarenheten från försöksanläggningen av filterbäddar ledde till att effektiviteten hos fler filter material undersöktes. I artikel VI beskrivs ett försök, gjord i laboratorium, där lakvatten från en soptipp som tar hand om industri avfall (metallavfall från bl.a. bilar och kylskåp) fick rinna genom kolonner med olika filtermaterial. Mixen av torv och aska med kolinnehåll visade sig vara bra på att ta bort både metaller och organiska ämnen från lakvattnet. Kunskapen från bl.a. dessa undersökningar har bidragit till att en fullskaleanläggning för lokal rening av lakvatten har kunnat byggas i anslutning till Stena metalls soptipp i Halmstad. Den andra delen i avhandlingsarbetet riktade in sig mot lakningstester. För att undersöka vilka ämnen som kan lakas ut från ett avfall rekommenderas två olika standardiserade lakningstests metoder. Vid den ena metoden pumpas en vätska genom en kolonn med en uppvägd mängd avfall tills ett visst vätske/fast fas förhållande (L/S halt) har uppnåtts. Vid den andra snabbare metoden, skakas en bestämd mängd avfall tillsammans med en bestämd volym vätska under 24 timmar. Den vätska som man får efter testerna kan jämföras med ett lakvatten och ska simulera den urlakning som avfallet ger ifrån sig under sin tid på deponin. Denna urlakningsvätska analyseras och de uppmätta halterna av olika ämnen jämförs med en gränsvärdes tabell och avfallet kan hänföras till en avfalls klass. De två lakningstesterna användes för att karakterisera olika avfallsslag, sönderdelat metall skrot (artikel IV) och slam från gatubrunnar (artikel V). För att få mer kunskap om metoderna och kunna vidareutveckla dem, utökades undersökningarna och analyserna. De urlakade vätskorna analyserades därför enligt Laqua protokollet, dvs med markörer för organiska miljögifter. Dessutom gjordes undersökningar där lakvatten användes som lakningsvätska istället för avjonat vatten som testmetoderna föreskriver. Dessa visade att den mer jonstarka vätskan (lakvattnet) ökade urlakningen av metaller från avfallet. En jämförelse av de två metoderna visade att den snabbare skaktesten oftast gav likvärdiga eller högre halter av de analyserade ämnena i urlakningsvätskan, och därmed kan den i många fall användas i första hand. För att bedöma ett filtermaterial ur ett livstidsperspektiv, utvecklades en strategi baserad på skaktester (artikel VII). Ett filtermaterial, en mix av torv och aska med kolinnehåll, undersökes före och efter att det använts i en filterbädd för rening av lakvatten. För att vara säker på att filtermaterialet i sig själv inte släppte ifrån sig några föroreningar gjordes en lakningstest. För att se hur effektivt materialet var på att ta bort metaller, PCB och fenolföreningar, gjordes skaktester med vätskor med kända halter av dessa föroreningar. När filtermaterialet är förbrukat och skall bytas ut anses det som ett avfall, och det karakteriserades med lakningstest för att hur det skulle tas om hand. Metodiken med skaktester ger bra information om utlakning från ett material, och skaktester är också bra instrument för att utvärdera ett filtermaterials effektivitet på att ta hand om metaller och opolära organiska ämnen som PCB. Men för att utvärdera effektiviteten av borttagandet av polära organiska ämnen (t ex. fenoler), är inte en korttids skak test något bra instrument. Reduceringen av dessa ämnen sker genom nedbrytning med hjälp av mikroorganismer, och för att undersöka detta behövs tester som varar en så lång tid att en mikrobiologisk miljö hinner etablera sig, t ex. kolonn tester. Utvärderingen av detta avhandlingsarbete visar på några ytterligare slutsatser och förslag till fortsatt arbete. Toxicitetstesten med Artemia bör kompletteras med tester på t ex. bakterier och växter, eftersom det inte räcker med en test på bara en organism för att bedöma giftigheten av en förorening ett naturligt ekosystem. Vidare behövs en biologisk test för att påvisa kroniska effekter, så som skador på fortplantning eller tumörsjukdomar. Dessa skador kan uppkomma genom att organismer påverkas under en lång tid av de låga, men därmed inte ofarliga halter av organiska miljögifter som ofta förekommer i lakvatten. Den presenterade metodiken kan användas för att utvärdera miljöfarliga ämnen från olika förorenade områden. Avhandlingen har visat att LAQUA protokollets sammansättning och dess analyser är ett bra instrument för att utvärdera reningstekniker för lakvatten och för att ge ytterligare information om organiska ämnen i fast avfall. Bedömning av luft kvalitet och karakterisering av dagvatten är andra exempel där metodiken kan användas. Avslutningsvis är det förstås lättare att utvärdera farligheten från avfall när det är mindre volymer avfall att utvärdera. Detta kan uppnås genom att konsumera mindre, återanvända produkter, återvinna material, utvinna energi ur avfallet och välja miljövänliga produkter när man köper nytt.
5

Estudo e caracterização geológica e geotécnica de rejeitos de mineração: Adrianópolis (PR) / Geological and geotechnical study and characterization in tailing: Adrianópolis (PR)

Raimondi, Isabela Monici 16 July 2014 (has links)
Os rejeitos de mineração provenientes do beneficiamento do minério, quando dispostos de maneira inadequada, podem causar a contaminação do solo e das águas superficiais e subterrâneas. Dependendo do tipo de minério tratado, tais rejeitos podem conter elevadas concentrações de metais potencialmente tóxicos e passar a atuar como fontes persistentes de liberação de tais metais através dos ecossistemas. Assim sendo, a caracterização desses rejeitos é extremamente importante. Neste contexto, foram realizadas caracterizações geológicas e geotécnicas nos rejeitos de mineração provenientes da região do Vale do Ribeira (município de Adrianópolis-PR), visando avaliar o grau de mobilidade e toxicidade dos metais contidos na porção superficial deste depósito. Para tanto, foram realizadas caracterizações mineralógicas (DRX e MEV/EDS), granulométricas, determinação dos parâmetros físico-químicos (pH, Eh e CE), além de ensaios que verificaram a mobilidade, especiação química e toxicidade das amostras: ensaios de solubilização, lixiviação, ensaio de variação de pH, extração sequencial e ecotoxicidade aquática envolvendo o organismo teste Daphnia similis. Além dos rejeitos foram realizadas análises mineralógicas e determinação dos parâmetros físico-químicos em amostras de estéril. A partir destas caracterizações, foi possível verificar que a composição mineralógica predominantemente no rejeito e no estéril é o carbonato, reflexo da litologia local. Tal composição refletiu também nos elevados valores de pH, que variaram de 7,6 a 8,0. Esses rejeitos apresentaram granulometria fina (predominância de areia muito fina, fina e silte), além de altas concentrações de metais, principalmente Pb (concentração média de 5.236,67 mg.kg-1 ) e Zn (7.726,53 mg.kg-1 ). Dos metais analisados, o Pb excedeu o valor preconizado na norma ABNT NBR 10.004:2004, tanto nos extratos lixiviados como nos solubilizados, para todas as amostras analisadas, o que permitiu classificar tais resíduos como Classe I - Perigoso. No ensaio de variação de pH, de forma geral, o Zn apresentou maior liberação na condição inicial mais ácida (pH 3), com média de liberação de 11,54 mg.L-1 após sessenta minutos de ensaio; embora nas outras condições também tenha ocorrido liberação considerável. A partir da extração sequencial, foi possível verificar que todos os metais (com exceção do Cu) estavam associados à fase de óxidos/hidróxidos, porém as fases consideradas de maior mobilidade (trocável e carbonática) estavam presentes em concentrações significativas para todos os metais analisados. As cinco amostras analisadas mostraram-se heterogêneas sendo que a RP5 e a RP7, apresentaram maior mobilidade dos metais Pb e Zn, além de terem apresentado maior toxicidade nos ensaios de ecotoxicidade. Para o ensaio de ecotoxicidade aquática, tais amostras apresentaram imobilidade dos neonatos até mesmo nas diluições menos concentradas (diluições contendo somente 6,2 e 3,1% de extrato solubilizado). Assim, concluiu-se que o rejeito pode ser considerado perigoso do ponto de vista ambiental, já que as altas concentrações de metais potencialmente tóxicos presentes estão passíveis de liberação e migração no ecossistema, podendo interagir com a biota aquática e terrestre. / Tailings from the ore processing when improperly disposed, can cause contamination of soil, surface water and groundwater. Depending on the treated ore, the mining waste may contain high concentrations of toxic metals and start acting as persistent metals sources to surrounding ecosystems. Therefore, the characterization of this material is extremely important. In this context, geological and geotechnical characterization were performed on tailings from Ribeira Valley (Adrianópolis-PR), in order to evaluate the mobility and toxicity of metals present in the superficial portion of the deposit. For the current paper the following tests were performed: mineralogical characterization (XRD and SEM/EDS), particle size distribution, determination of physical and chemical properties (pH, Eh and EC), solubilization and leaching tests, pH variation, sequential extraction and aquatic ecotoxicity were carried out. Besides the tailings analyzes, mineralogical characterization and pH measurements were also performed in samples from Perau (waste rock). The results showed mineralogical compositions predominantly carbonate in both tailing and Perau samples, as a reflection of the local lithology. This composition also reflected in the higher pH values, which ranged from 7.6 to 8.0. The tailing had fine particle size (predominance of silt, very fine and fine sand), and high concentrations of metals, especially Pb (average concentration of 5236.67 mg.kg-1) and Zn (7726.53 mg.kg-1). The metal Pb was above of the recommended value in ABNT NBR 10.004:2004 in leaching tests, solubilization tests and for all samples. This fact allowed the classification of the waste as Class I-Dangerous. In testing of pH variation, the Zn showed higher release in initial acidic condition (pH 3), releasing average 11.54 mg.L-1 after sixty minutes of test; although in others pH conditions have also been considerable release. In sequential extraction, the results found that all metals (except Cu) were associated with phase oxides/hydroxides, but the phases considered more mobile (exchangeable and carbonate) were also present in significant concentrations for all metals. The five samples were considered heterogeneous and two of them (RP5 and RP7) had greater mobility of Pb and Zn, besides a higher toxicity in ecotoxicity tests. In aquatic ecotoxicity test, the samples showed immobility of neonates organisms even in less concentrated dilutions (dilutions containing only 6.2 and 3.1% solubilized extract). In conclusion, the waste may be considered problematic for environment, because the high concentrations of toxic metals present in tailing can be released from it and migrate to the ecosystems, causing exposure to terrestrial and aquatic organisms.
6

Use Of Waste Pyrite From Mineral Processing Plants In Soil Remediation

Aydin, Gulsen 01 November 2011 (has links) (PDF)
Pyrite (FeS2) is commonly present in complex sulphide ores in significant amounts. After the enrichment of such ores by flotation, pyrite is either produced as a separate concentrate and sold to acid manufactures or removed and disposed off as tailing. Due to lack of demand from manufacturers, most of pyrites is usually disposed off as tailing. Therefore, pyrite is usually a waste from complex sulphide ores. Yet, it may be a remediation additive for calcareous soils and calcareous- alkali soils deficient in Fe and other micronutrients such as Cu, Zn and Mn. Waste pyrite may be also an alternative amendment to gypsum because of the production of sulphuric acid which is effectively used in the reclamation of calcareous alkali soils. The effectiveness of adding waste pyrite and sulphuric acid produced from waste pyrite to calcareous-alkali soil (Sarayk&ouml / y-Ankara) and calcareous soil (Gaziantep) was studied under laboratory conditions. Pure gypsum was also used as an amendment for the comparison of the effectiveness of waste pyrite in the reclamation of alkali soils. Gypsum, powder waste pyrite and sulphuric acid were applied to the soil with reference to the gypsum requirement (GR) of the soils. Greenhouse pot tests were carried out with wheat as test plant to determine the effect of waste pyrite treatment on the plant yield (wheat) and on the amount of micronutrient (Fe, Cu, Zn, Mn) essential for plant growth. Hazard potential of pyritic tailings in terms of heavy metal contamination was also taken into account. The results showed that the soil pH and exchangeable sodium percentage (ESP), indicators of alkalization, decreased upon pyrite addition to calcareous- alkali soils of Sarayk&ouml / y-Ankara. It was also found that pyritic tailings were effective in the increasing level of essential micronutrients (Fe, Cu, Zn and Mn) for plant growth in both soils. This was ascertained by the dry matter yield of the plants in the green house pot tests. Heavy metal toxicity caused by pyrite which is a rightful concern remained well below the legal limits in the soils. Thus, it was concluded that the application of pyritic tailings promoted rapid amelioration of calcareous-alkali soil (Sarayk&ouml / y-Ankara) and calcareous soil (Gaziantep) with no deleterious heavy metal contamination.
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Estudo e caracterização geológica e geotécnica de rejeitos de mineração: Adrianópolis (PR) / Geological and geotechnical study and characterization in tailing: Adrianópolis (PR)

Isabela Monici Raimondi 16 July 2014 (has links)
Os rejeitos de mineração provenientes do beneficiamento do minério, quando dispostos de maneira inadequada, podem causar a contaminação do solo e das águas superficiais e subterrâneas. Dependendo do tipo de minério tratado, tais rejeitos podem conter elevadas concentrações de metais potencialmente tóxicos e passar a atuar como fontes persistentes de liberação de tais metais através dos ecossistemas. Assim sendo, a caracterização desses rejeitos é extremamente importante. Neste contexto, foram realizadas caracterizações geológicas e geotécnicas nos rejeitos de mineração provenientes da região do Vale do Ribeira (município de Adrianópolis-PR), visando avaliar o grau de mobilidade e toxicidade dos metais contidos na porção superficial deste depósito. Para tanto, foram realizadas caracterizações mineralógicas (DRX e MEV/EDS), granulométricas, determinação dos parâmetros físico-químicos (pH, Eh e CE), além de ensaios que verificaram a mobilidade, especiação química e toxicidade das amostras: ensaios de solubilização, lixiviação, ensaio de variação de pH, extração sequencial e ecotoxicidade aquática envolvendo o organismo teste Daphnia similis. Além dos rejeitos foram realizadas análises mineralógicas e determinação dos parâmetros físico-químicos em amostras de estéril. A partir destas caracterizações, foi possível verificar que a composição mineralógica predominantemente no rejeito e no estéril é o carbonato, reflexo da litologia local. Tal composição refletiu também nos elevados valores de pH, que variaram de 7,6 a 8,0. Esses rejeitos apresentaram granulometria fina (predominância de areia muito fina, fina e silte), além de altas concentrações de metais, principalmente Pb (concentração média de 5.236,67 mg.kg-1 ) e Zn (7.726,53 mg.kg-1 ). Dos metais analisados, o Pb excedeu o valor preconizado na norma ABNT NBR 10.004:2004, tanto nos extratos lixiviados como nos solubilizados, para todas as amostras analisadas, o que permitiu classificar tais resíduos como Classe I - Perigoso. No ensaio de variação de pH, de forma geral, o Zn apresentou maior liberação na condição inicial mais ácida (pH 3), com média de liberação de 11,54 mg.L-1 após sessenta minutos de ensaio; embora nas outras condições também tenha ocorrido liberação considerável. A partir da extração sequencial, foi possível verificar que todos os metais (com exceção do Cu) estavam associados à fase de óxidos/hidróxidos, porém as fases consideradas de maior mobilidade (trocável e carbonática) estavam presentes em concentrações significativas para todos os metais analisados. As cinco amostras analisadas mostraram-se heterogêneas sendo que a RP5 e a RP7, apresentaram maior mobilidade dos metais Pb e Zn, além de terem apresentado maior toxicidade nos ensaios de ecotoxicidade. Para o ensaio de ecotoxicidade aquática, tais amostras apresentaram imobilidade dos neonatos até mesmo nas diluições menos concentradas (diluições contendo somente 6,2 e 3,1% de extrato solubilizado). Assim, concluiu-se que o rejeito pode ser considerado perigoso do ponto de vista ambiental, já que as altas concentrações de metais potencialmente tóxicos presentes estão passíveis de liberação e migração no ecossistema, podendo interagir com a biota aquática e terrestre. / Tailings from the ore processing when improperly disposed, can cause contamination of soil, surface water and groundwater. Depending on the treated ore, the mining waste may contain high concentrations of toxic metals and start acting as persistent metals sources to surrounding ecosystems. Therefore, the characterization of this material is extremely important. In this context, geological and geotechnical characterization were performed on tailings from Ribeira Valley (Adrianópolis-PR), in order to evaluate the mobility and toxicity of metals present in the superficial portion of the deposit. For the current paper the following tests were performed: mineralogical characterization (XRD and SEM/EDS), particle size distribution, determination of physical and chemical properties (pH, Eh and EC), solubilization and leaching tests, pH variation, sequential extraction and aquatic ecotoxicity were carried out. Besides the tailings analyzes, mineralogical characterization and pH measurements were also performed in samples from Perau (waste rock). The results showed mineralogical compositions predominantly carbonate in both tailing and Perau samples, as a reflection of the local lithology. This composition also reflected in the higher pH values, which ranged from 7.6 to 8.0. The tailing had fine particle size (predominance of silt, very fine and fine sand), and high concentrations of metals, especially Pb (average concentration of 5236.67 mg.kg-1) and Zn (7726.53 mg.kg-1). The metal Pb was above of the recommended value in ABNT NBR 10.004:2004 in leaching tests, solubilization tests and for all samples. This fact allowed the classification of the waste as Class I-Dangerous. In testing of pH variation, the Zn showed higher release in initial acidic condition (pH 3), releasing average 11.54 mg.L-1 after sixty minutes of test; although in others pH conditions have also been considerable release. In sequential extraction, the results found that all metals (except Cu) were associated with phase oxides/hydroxides, but the phases considered more mobile (exchangeable and carbonate) were also present in significant concentrations for all metals. The five samples were considered heterogeneous and two of them (RP5 and RP7) had greater mobility of Pb and Zn, besides a higher toxicity in ecotoxicity tests. In aquatic ecotoxicity test, the samples showed immobility of neonates organisms even in less concentrated dilutions (dilutions containing only 6.2 and 3.1% solubilized extract). In conclusion, the waste may be considered problematic for environment, because the high concentrations of toxic metals present in tailing can be released from it and migrate to the ecosystems, causing exposure to terrestrial and aquatic organisms.
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Environmentální charakteristiky minerálních odpadů z metalurgie / Environmental characteristics of mineral waste from metallurgy

Vítková, Martina January 2013 (has links)
Mineralogical and geochemical characteristics of metallurgical wastes from the Cu-Co smelters situated in the Zambian Copperbelt have been investigated. A number of instrumental analytical methods (XRD, SEM/EDS, EPMA, TEM/EDS) has been used to identify primary and secondary phases in smelter slags and dusts. A set of leaching experiments (CEN/TS 14997 pH-static test, EN 12457 batch test) in combination with geochemical modelling has been performed, with the emphasis on the leaching behaviour of potential contaminants and their release as a function of the pH. The effect of sample preparation on metal leachability from slag was also evaluated, considering the grain size reduction required by the standardised leaching protocols. Environmental and health risk assessments of the dust samples have been performed. It was shown that the main carriers of metals in the studied slags were Cu sulphides (bornite, digenite, chalcocite), Co sulphides (cobaltpentlandite), Co-bearing intermetallic phases and alloys. Copper and cobalt were detected in major silicates and spinels, substituting for Fe or Mg in their structures, and in glass. The presence of secondary metal-bearing phases observed on the slag surfaces indicated the reactivity of the slags on contact with water/atmosphere. It was reported that in...
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Investigação geoambiental em áreas de disposição de resíduos sólidos urbanos utilizando a tecnologia do piezocone. / Geoenvironmental site investigation in waste disposal sites using the piezocone technology.

Mondelli, Giulliana 14 April 2004 (has links)
O principal objetivo deste trabalho foi estudar a aplicabilidade da tecnologia do piezocone na investigação geoambiental de solos tropicais a partir da realização de ensaios nas áreas onde se encontram o aterro de resíduos sólidos urbanos de Bauru e o antigo lixão de Ribeirão Preto, ambos no Estado de São Paulo. Dentro deste contexto, outros ensaios de campo e de laboratório foram analisados para um melhor entendimento do caminhamento da pluma de contaminação e dos próprios resultados dos ensaios com piezocone realizados nestas áreas de disposição de resíduos. A tecnologia do piezocone apresentou limitações quando empregada na área do antigo lixão de Ribeirão Preto, uma vez que o impenetrável do cone foi atingido antes do nível d’água, impossibilitando assim a identificação da posição deste, a estimativa da permeabilidade do solo e a coleta de amostras de água. Os ensaios de eletrorresistividade de superfície permitiram a detecção do formato e do sentido do caminhamento da pluma de contaminação e foram fundamentais para a orientação dos locais onde foram realizados os ensaios de piezocone e amostragem de solo e água nas duas áreas estudadas. Os resultados dos ensaios com o piezocone de resistividade (RCPTU) realizados no aterro de resíduos sólidos urbanos de Bauru mostraram que os valores de resistividade são fortemente afetados pelo grau de saturação, gênese, textura e tipo de argilo-mineral presente na fração fina do solo. Constatou-se que o ensaio RCPTU possibilitou identificar zonas com presença de poluentes, as quais foram confirmadas a partir da análise conjunta dos resultados dos ensaios de geofísica de superfície e das amostras de solo e água coletadas com os amostradores do sistema direct-push e dos poços de monitoramento. Este trabalho apresenta ainda resultados preliminares de ensaios de laboratório, que foram úteis para avaliar a capacidade de retenção do solo que ocorre no entorno do aterro de resíduos sólidos urbanos de Bauru para os metais Ni, Zn, Cd e Pb. Os resultados dos ensaios de adsorção em lote e de coluna indicam que a poluição no entorno deste aterro pode estar ocorrendo de forma lenta, destacando-se a importância da continuidade do monitoramento do aqüífero local. / The major purpose of this dissertation is to study the applicability of the piezocone technology for geoenvironmental site investigation of tropical soils. Two waste disposal sites were investigated: a deactivated dumpsite in Ribeirão Preto and a sanitary landfill in Bauru, in São Paulo State, Brazil. Other in situ and laboratory tests were carried out in these two areas for a better understanding of the leacheate plume and of the results gathered with piezocone tests. The piezocone technology presented limitations to investigate Ribeirão Preto site, since groundwater level is deeper than the impenetrable to the cone. For reason, it was impossible to estimate permeability and no water samples using the direct-push technology were obtained. Geophysical tests carried out at the two studied sites allowed to detect and delineate the shape of leachate plume. They were fundamental to guide and locate the piezocone tests, soil and water sampling and monitoring wells. The resistivity piezocone tests (RCPTU) carried out in Bauru site showed that the resistivity values are very affected by degree of saturation, genesis, fabric and clay mineral type. Geophysical tests results, soil and water samples collected by direct-push technology and by monitoring wells supported the interpretation of RCPTU tests. These tests were able to identify polluted zones. Preliminary laboratory tests were carried out to access retention of Ni, Zn, Cd and Pb by the soil from Bauru site. The results of leaching and batch equilibrium tests indicated that pollution around this site is taking place slowly, emphasizing the importance to continue monitoring groundwater.
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Investigação geoambiental em áreas de disposição de resíduos sólidos urbanos utilizando a tecnologia do piezocone. / Geoenvironmental site investigation in waste disposal sites using the piezocone technology.

Giulliana Mondelli 14 April 2004 (has links)
O principal objetivo deste trabalho foi estudar a aplicabilidade da tecnologia do piezocone na investigação geoambiental de solos tropicais a partir da realização de ensaios nas áreas onde se encontram o aterro de resíduos sólidos urbanos de Bauru e o antigo lixão de Ribeirão Preto, ambos no Estado de São Paulo. Dentro deste contexto, outros ensaios de campo e de laboratório foram analisados para um melhor entendimento do caminhamento da pluma de contaminação e dos próprios resultados dos ensaios com piezocone realizados nestas áreas de disposição de resíduos. A tecnologia do piezocone apresentou limitações quando empregada na área do antigo lixão de Ribeirão Preto, uma vez que o impenetrável do cone foi atingido antes do nível d’água, impossibilitando assim a identificação da posição deste, a estimativa da permeabilidade do solo e a coleta de amostras de água. Os ensaios de eletrorresistividade de superfície permitiram a detecção do formato e do sentido do caminhamento da pluma de contaminação e foram fundamentais para a orientação dos locais onde foram realizados os ensaios de piezocone e amostragem de solo e água nas duas áreas estudadas. Os resultados dos ensaios com o piezocone de resistividade (RCPTU) realizados no aterro de resíduos sólidos urbanos de Bauru mostraram que os valores de resistividade são fortemente afetados pelo grau de saturação, gênese, textura e tipo de argilo-mineral presente na fração fina do solo. Constatou-se que o ensaio RCPTU possibilitou identificar zonas com presença de poluentes, as quais foram confirmadas a partir da análise conjunta dos resultados dos ensaios de geofísica de superfície e das amostras de solo e água coletadas com os amostradores do sistema direct-push e dos poços de monitoramento. Este trabalho apresenta ainda resultados preliminares de ensaios de laboratório, que foram úteis para avaliar a capacidade de retenção do solo que ocorre no entorno do aterro de resíduos sólidos urbanos de Bauru para os metais Ni, Zn, Cd e Pb. Os resultados dos ensaios de adsorção em lote e de coluna indicam que a poluição no entorno deste aterro pode estar ocorrendo de forma lenta, destacando-se a importância da continuidade do monitoramento do aqüífero local. / The major purpose of this dissertation is to study the applicability of the piezocone technology for geoenvironmental site investigation of tropical soils. Two waste disposal sites were investigated: a deactivated dumpsite in Ribeirão Preto and a sanitary landfill in Bauru, in São Paulo State, Brazil. Other in situ and laboratory tests were carried out in these two areas for a better understanding of the leacheate plume and of the results gathered with piezocone tests. The piezocone technology presented limitations to investigate Ribeirão Preto site, since groundwater level is deeper than the impenetrable to the cone. For reason, it was impossible to estimate permeability and no water samples using the direct-push technology were obtained. Geophysical tests carried out at the two studied sites allowed to detect and delineate the shape of leachate plume. They were fundamental to guide and locate the piezocone tests, soil and water sampling and monitoring wells. The resistivity piezocone tests (RCPTU) carried out in Bauru site showed that the resistivity values are very affected by degree of saturation, genesis, fabric and clay mineral type. Geophysical tests results, soil and water samples collected by direct-push technology and by monitoring wells supported the interpretation of RCPTU tests. These tests were able to identify polluted zones. Preliminary laboratory tests were carried out to access retention of Ni, Zn, Cd and Pb by the soil from Bauru site. The results of leaching and batch equilibrium tests indicated that pollution around this site is taking place slowly, emphasizing the importance to continue monitoring groundwater.

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