• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 441
  • 412
  • 48
  • 34
  • 33
  • 27
  • 21
  • 15
  • 15
  • 15
  • 15
  • 15
  • 15
  • 15
  • 13
  • Tagged with
  • 1291
  • 1291
  • 375
  • 369
  • 256
  • 198
  • 158
  • 142
  • 115
  • 109
  • 105
  • 101
  • 96
  • 71
  • 70
  • 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.
351

Förbättringsförslag till Kanalen i Sandviken : SWOT-analys av förbättringsförslagen

Lööv, Amanda January 2016 (has links)
The urban area of Sandviken is founded on industries, which also is the driving force of growth throughout the years. The industry were in need of a nearby and easily accessed water source, and therefore a channel was excavated. The name of that channel today is Kanalen and it has three uses: stormwater recipient, natural element and cultural heritage.The environmental load on Sanvikens urban areas are increasing along with Sandvikens population. This lead to issues regarding the possibility to maintain Kanalen and all its three functions in the future. The purpose of this paper is to present suitable improvements that can be made based on the present situation, limited to traffic and solid waste disposal. The physical boundary of Sandvikens community is Sandvikens’ northern urban part. The goal is to obtain knowledge of both the present situation as well as suitable improvements. To understand the so-called Strength, Weaknesses, Opportunities and Threats(SWOT) analysis is also an interest. The target group is foremost the public servants in the community, however it could also be local residents. The method and method implementation are presented in chronological order in the paper. The literature study is based on several annual reports and secondary literature, as well as database research. Visits to Kanalen were performed in order to take relevant photos and make realistic observations on the physical conditions in and around Kanalen. Interviews took place with people who could contribute to the comprehension of the complexity of Kanalen. Both regarding its significance and additional information. SWOT is the analysis used on the suggested improvements eligibility for Sandviken. The tool was consistent throughout each of the improvements suggested. The results section of the paper is meant to function as an informative foundation and a foundation up for discussion. The description of the current situation consists of figures, pictures and substance levels. The description has two main parts. The first includes the physical aspects of Kanalen and surrounding territory. Points of emission from storm drains to Kanalen and aspects of each function as presented. Further information in that chapter of the paper include an earlier event of landslip and Sandvikens green area. Focus then move to traffic and waste pollution. Specific points of pollution from traffic are roundabouts, traffic lights, and paved roads going directly across Kanalen using bridges. Leaked substances from traffic were found mainly to be nutrients like nitrogen and phosphorus, and heavy metals. The solid waste studied in this paper was concentrated on paths in very close proximity to Kanalen, which is used for walking and biking. The outcome of mapping these paths showed that all waste containers were suitable for the intended task. The environmental impact of nutrients and heavy metals retrieved from the annual report were described in general terms. The reason is to show the risks involved with unsupervised and increasing substance levels. Four improvements on traffic pollution and three on waste are presented in the result section. The improvements to traffic pollution to Kanalen in Sandvikens urban area were degreasers, bio-indicators, permeable pavement coatings and plant beds. These improvements could lead to the following positive effects, less downstream work, enhanced esthetical value despite change, and a lasting heritage. The improvements on waste pollution to Kanalen in Sandvikens urban area were to rectify unsuitable waste containers, implement new and improve illumination along Kanalen. These improvements could lead to following positive effects, preferable biological conditions, less visible waste, and the use of modern solutions that are future friendly. Possible errors associated with this study can be choice of method, use of figures and tables and content that maybe should have been included. However, the following conclusions canebe made from this study. The environmental strain could be reduced if suggested improvements are carried out. The advantages concern all three functions of Kanalen. The proportions of each improvement have an effect on the feasibility. Budget and possibility to coordinate are also decisive elements. This work is meant to lead to environmental advantageous change, both in the aquatic setting in Kanalen as well as in its physical surroundings. / Sandvikens tätort är byggd kring industrin som fick den att börja växa. Industrin behövde en vattenkälla vilket innebar att en kanal grävdes fram. Kanalen är namnet idag och har tre funktioner: dagvattenrecipient, naturinslag och kulturarv. Miljöbelastningen ökar i samband med att tätorten och Sandvikens invånarantal växter. Detta innebär problematik beträffande möjligheten att bibehålla Kanalens tre funktioner även i framtiden. Syftet med arbetet är att presentera förbättringar som kan göras baserat på nuläget vid Kanalen, avgränsat till trafik och avfallsområdena. Sandviken norra tätort är den fysiska avgränsningen i kommunen. Målen är att erhålla kompetens om både dagsläget och lämpliga förbättringar, samt att förstå Strength, Weaknesses, Opportunities and Threats(SWOT) till bästa förmåga. Målgruppen är främst Sandvikens kommun men kan likväl vara residenter i kommunen. Metoden och genomförande av metoden presenteras i kronologisk ordning. Litteraturstudien innehåller årsrapporter och sekundärlitteratur, samt databassökning på internet. Studiebesök gjordes på Kanalen för att ta fotografier och erhålla en verklighetsuppfattning av de fysiska förhållandena i och kring Kanalen. Intervjuer gjordes med personer som kunde bidra till förståelsen av Kanalens komplexa betydelse inom kommunen och kompletterande fakta. SWOT är analysmetoden vald för att analysera rekommenderade förslagens lämplighet. Analysverktyget användes konsekvent på varje förbättringsförslag. Resultatdelen med SWOT är menat att fungera som ett informativt underlag och underlag upp för diskussion. I nulägesbeskrivningen presenteras dagsläget på Kanalen med figurer, bilder och substansnivåer. Nulägesbeskrivningen är uppdelad i två huvuddelar. Första delen beskriver Kanalens fysiska utformning och de tre funktionerna. Utsläppspunkter från dagvattenledningarna till Kanalen visas, samt andra tillhörande aspekter av varje funktion. Ett tidigare ras på Kanalen och Sandvikens grönområde förekommer. Därefter presenteras föroreningskällorna trafiken och avfall. Punkter för utsläpp från trafiken som leder till trafikdagvatten i Sandvikens norra tätort är rondeller, trafikljus och vägar som går direkt över Kanalen via broar. Läckageämnen från trafiken pekade på bland annat näringsämnena kväve och fosfor, samt tungmetaller. Avfallsdelen koncentrerades till gång- och cykelbanorna i direkt anslutning till Kanalen. Utfallet från kartläggningen visade att alla sopkärl inte var optimala för ändamålen. Miljökonsekvenserna av näringsämnen och tungmetaller funna i årsrapporterna beskrevs för att visa riskerna involverade med okontrollerade och ökande nivåer. Resultatdelen med en förklaring av förbättringsförslagen och SWOT-analyser innefattar fyra förbättringsförslag på trafiken och tre förslag på avfall. Förslagen gällande trafiken är oljeavskiljare, bioindikatorer, genomsläppliga beläggningar, och växtbäddar. Föregående förslag kan leda till följande positiva konsekvenser, mindre nedströmsarbete, ökat estetiskt värde trots förändring, och ett hållbart arv. Förslagen gällande avfall är åtgärda befintliga sopkärl, introducera nya och förbättra belysningen. Effekterna kan leda till följande positiva konsekvenser, bättre biologiska förhållanden, mindre synligt avfall och moderna lösningar som kan hålla inför framtiden. Felkällor i arbetet exponeras efterföljande kapitel och berör ämnen som metodval, figur och tabellhantering, och innehåll som eventuellt borde ha inkluderats men inte gjorts. Från arbete kan följande slutsatser utvinnas. Miljöbelastningen kan minskas om förbättringsförslagen utförs. Fördelarna berör alla Kanalens tre funktioner. Omfattningarna av förslagen påverkar hur genomförbara förslagen i tätorten är. Budget och möjligheten till samordning är också faktorer som har avgörande roller. Arbetet är menat att förändra på ett miljöfördelaktigt
352

The impacts of feedlot effluent on aquatic freshwater systems

26 May 2010 (has links)
M.Sc. / This study aims to assess the potential impacts of intense feedlot activity on the aquatic freshwater environment, with reference to three feedlots, ranging in production size and all situated in the upper Vaal catchment area. Field assessments were done over a high flow and low flow period, while controlled exposures were also done to quantify a potential stress reaction to growth hormone exposure (using Clarias gariepinus as test organism). It was ascertained that water quality variables contributing towards differences between upstream and downstream environmental conditions are NH4 concentrations pH and conductivity. Lead concentrations were also periodically higher downstream from feedlot activity, in comparison with upstream. Taking the sediment assimilation potential of growth hormones into consideration, it was determined that Feedlot C showed the highest assimilation potential, while Feedlot A reflected the lowest. Alterations on family level invertebrate community structures indicated a categorical decline in abundances and species richness at sites situated downstream from feedlots. However, some clear seasonal influences were also observed. Further community and diversity analyses reflected alterations in invertebrate community structures that were not reflected in SASS 5 scores. With regards to the biomarkers applied in this study, it was noted that there was a significant (p<0.05) difference in the cellular energy allocation (CEA) between control and hormone exposed groups. The total amount of energy available (Ea) increased significantly for test organisms exposed to Diethylstilbestrol (DES), while there was a significant increase in energy consumption (Ec) of test organisms exposed to Trenbolone acetate (TBA). In addition to CEA, metabolic profiling of blood plasma was also performed, which indicated a definite ordination in metabolic constituents after fifteen days of exposure. This was established by subjecting the data to principle component analysis (PCA), which accounted for 83 % variance observed. The impacts and biotic responses identified in this study were contextualised with known literature on the effects of feedlot activity and growth hormone exposure on the aquatic environment. Finally, conclusions were drawn and recommendations made with regard to improving feedlot operational activities. The results obtained in this study contribute towards an integrated framework for the environmental management of feedlot activities.
353

Evaluation of a health assessment index with reference to bioaccumulation of metals in Labeo species and aspects of the morphology of Chonopeltis victori

17 November 2014 (has links)
M.Sc. (Zoology) / Please refer to full text to view abstract
354

Clinoptilolite-polypropylene composites for the remediation of water systems polluted with heavy metals and phenolic compounds

07 June 2012 (has links)
M.Sc. / In this study, natural and modified clinoptilolite (CLI) reinforced polypropylene (PP) composites possessing improved mechanical and adsorptive properties were prepared through melt-mixing. Determination of morphological, structural and thermal properties was achieved by means of different techniques (FTIR, TGA, DSC, electron microscopy and x-ray spectroscopy). Electron microscopy revealed that increasing filler loading beyond 20% leads to agglomeration of clinoptilolite particles reducing their dispersion within the matrix. Thermal studies showed that the reinforced composites had a lower thermal stability than the neat PP polymer, suggesting that the clinoptilolite interfered with polymer chain arrangement and bonding. It also showed that percentage crystallinity increased with increasing filler loading indicating that the filler particles acted as nucleating agents within the polymeric matrix during composite synthesis. Prior to the ion-exchange studies, water sorption behaviour of fabricated composites was evaluated because ion-exchange/adsorption studies were to be performed in aqueous media. It was therefore observed that the hydrophobic polymer, PP attained the property of water sorption mainly due to the porous structure of the composites created by mixing and extrusion and also by the addition of the hydrophilic filler material.
355

Regression Analysis of Dissolved Heavy Metals in Storm Water Runoff from Elevated Roadways

Erlacher, Ruben 21 May 2005 (has links)
This proposed research focused on the prediction and identification of dissolved heavy metals in storm water runoff from elevated roadways. Storm water runoff from highways transports a significant load of contaminants, especially heavy metals and particulate matter, to receiving waters. Heavy metals, either in dissolved or particulatebound phases, are unique in the fact that unlike organic compounds, they are not degraded in the environment. The objective of this research was to develop a mathematical model to relate dissolved heavy metal concentration to different measurable parameters which are easily available and routinely measurable for elevated roadways. The reliability of the developed models was then evaluated by comparing the raw data versus data predicted by the models. The test site for this research was selected at the intersection of the Interstate-10 and Interstate-610, Orleans Parish, New Orleans, Louisiana. Subsequently a research test site was developed and highway storm water runoff was collected. Volumetric flow rates were measured with every collected sample by measuring the amount of collected water and the collection time. Storm water runoff from the examined elevated roadway section was sampled for 10 storm events throughout the course of the study from which hydrologic and water quality data were collected. The measurement of different parameters made it possible to determine the percentage of dissolved heavy metal mass loading and the characterization of high runoff flow intensity and low runoff flow intensity storm events. Another very important achievement in this research was the construction of a predictive model for dissolved heavy metal concentrations based on field measurements. Data analysis proceeded by applying different variable selection statistical methods as well as multiple regression analyses in order to evaluate the simultaneous effects of all variables on the concentration of dissolved heavy metals in storm water runoff. The developed model enables the user to predict dissolved heavy metal concentrations with known field measurements within a prediction interval of 95 % confidence. The reliability of the models was verified by carrying out significant-difference tests for both sets of data, observed and predicted, for a 5% of significance level.
356

Weathering of metallurgical slags : a comprehensive study on the importance of chemical and biological contributions / L'altération des scories métallurgiques : une étude approfondie sur l'importance des contributions chimiques et biologiques

Yin, Nang Htay 02 December 2014 (has links)
Le crassier du site MetalEurop (Noyelles-Godault) a accueilli des scories de première fusion entre les années 1936 à 2003. Il est actuellement constitué de 4 millions de tonnes de ces matériaux générés par les deux procédés pyrométallurgiques les plus usités dans le monde pour la production du plomb et du zinc : le procédé Lead Blast Furnace (LBF) et le procédé Impérial Smelting Furnace (ISF). L'utilisation de ces scories en tant que matériau de substitution dans les ciments et dans les routes a été envisagée et a fait l'objet de recherches, mais présente des risques environnementaux, c'est-à-dire, essentiellement la dissémination de polluants (Pb et Zn) / Primary smelting slags, known as Lead Blast Furnace (LBF) and Imperial Smelting Furnace (ISF), were generated by the former pyrometallurgical industries located in Noyelles-Godault, Northern France. Following its closure in 2003, 4 million tons of primary slags have been landfilled as a heap in the vicinity of the Deûle River, near the industrial basin of Nord-Pas-de-Calais. These slag materials are often enriched in particular metals (Pb, Zn) that can be released into the environment through alteration processes and leaching. Many biological and chemical processes might take place within these tailings and thus affect significantly the slag weathering. Predicting the environmental impact of these wastes requires an understanding of the mineral-water interactions as well as the influence of the biological activities (the involvement of microorganisms). Thus, this research is designed to simulate the natural weathering of slag by simulating different weathering conditions with or without the involvement of the microorganisms as well as by varying several chemical parameters. Chemical weathering of both LBF and ISF slags was studied by as a function of pHs (4, 5.5, 7, 8.5 and 10) as well as under two atmospheres (open air and nitrogen). Significant amounts of Ca, Fe and Zn were released under acidic conditions (pH 4) with a decrease towards the neutral to alkaline conditions (pH 7 and 10) for both slags. The concentrations of all elements increased gradually after 216 h compared to initial 24 h of leaching period. The presence of oxygen under open-air atmosphere not only enhanced oxidative weathering but also encouraged formation of secondary oxide and carbonate phases. In addition, Zn dissolution was related to extremes zinc isotopic signatures in the leachate; heavier δ66Zn values at low pH than at high pH for both slags under open-air atmosphere. On the other hand, bioweathering of both slags was studied in the presence of a pure heterotrophic bacterial strain (Pseudomonas aeruginosa) in a bioreactor operated in batch conditon as well as in a semi-flow through reactor with intermittent leachate renewal conditions. P. aeruginosa is shown to play a significant role in slags weathering by enhancing the leaching and solubility of Zn and Pb. In addition, the cumulative bulk release of dissolved Fe, Si, Ca and Mg doubled in the presence of bacteria, probably due to the release of soluble complexing organic molecules (e.g. siderophores). Bacterial biomass served as the bioadsorbent for Pb, Fe and Zn as 70-80% of Pb and Fe, 40-60% of Zn released are attached to and immobilized by the bacterial biomass. Oxides, hydroxides and carbonates were predicted as secondary phases during chemical weathering of slags whereas carbonates and phosphates were dominant phases during bioweathering. These predictions were in agreement with the observations by Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDS), Transmission Electron Microscopy (TEM) analysis, and X-ray Photoelectron Spectroscopy (XPS) analysis
357

[en] BIOSORPTION OF CO(II) AND NI(II) FROM AQUEOUS SOLUTIONS USING RHODOCOCCUS RUBER STRAIN / [pt] BIOSSORÇÃO DE CO(II) E NI(II) CONTIDOS EM SOLUÇÕES AQUOSAS UTILIZANDO A CEPA RHODOCOCCUS RUBER

EDSON BORGES DA SILVA NETO 12 June 2012 (has links)
[pt] A água, recurso natural imprescindível, encontra-se cada vez mais escassa e imprópria para o consumo humano. A biossorção é uma tecnologia que utiliza diversos tipos de biomassas, entre elas microrganismos não patogênicos, como Rhodococcus ruber. O objetivo deste trabalho visa a remoção de Co(II) e Ni(II) presentes em soluções aquosas utilizando R. ruber. Estudos microbiológicos, ensaios de biossorção em batelada foram realizados para testar a eficiência da biomassa nos metais pesados Co(II) e Ni(II) através dos parâmetros: pH, concentração de biomassa e concentração do metal. A cinética da reação foi estudada e as isotermas confeccionadas. Espectrometria no infravermelho potencial zeta e microscopia eletrônica foram técnicas utilizadas para conhecimento dos elementos envolvidos no processo biossortivo. Uma remoção de 44 por cento de Co(II) e 36,6 por cento de Ni(II) da solução foi obtida em pH 6 após 180 minutos de contato em solução contendo 3 g.L(-1) de biomassa e 30 mg.L(-1) de metal. A partir da concentração de biomassa de 3 g.L1, observou-se redução na remoção do metal tanto para Co(II) quanto para Ni(II). A isoterma que melhor se ajustou no estudo em questão foi Freundlich para os dois metais. O modelo de pseudo-segunda ordem foi o mais indicado nos estudos cinéticos realizados para os íons Co(II) e Ni(II). Quando avaliados os melhores parâmetros, não foram incrementados grandes graus de remoção utilizando mais uma ou duas fases de biomassa nova na solução. O tratamento da biomassa com NaOH foi o mais eficiente elevando a remoção para 97 por cento de Co(II) e 89,1 por cento de Ni(II). / [en] Water, essential natural resource, is becoming increasingly scarce and unfit for human consumption. The biosorption is a technology that uses various types of biomass, including nonpathogenic microorganism suchs Rhodococcus rubber. This study aims at the removal of Co(II) and Ni(II) present in aqueous solutions using R. rubber. Microbiological studies, batch biosorption test were conducted to test the efficiency of biomass in heavy metals Co(II) and Ni(II) through the pH, biomass concentration and concentration of the metal. The reaction kinetics was studie and the isotherms made. Zeta potencial, infrared spectrometry and electron microscopy techniques were used for knowledge of the elements involved microscopy techniques were used for knowledge of the elements involved in the process biosorption. A 44 per cent removal of Co(II) and 36.6 per cent Ni(II) solution at pH 6 was obtained after 180 minutes of contact in a solution containing 3 g.L(-1) of biomass and 30 mg.L(-1) of metal solution. From the concentration of biomass 3 g.L(-1), there was a reduction in metal removal for both Co(II) and for Ni(II). The isotherm best fit in the current study was Freundlich for the two metals. The model of pseudo-second order was the best in the kinetic studies performed for the Co(II) and Ni(II). When considering the best parameters, therewere increased levels of large removal using one or two phases of new biomass in the solution. Treatment of biomass with NaOH was the most efficient removal rising to 97 per cent of Co(II) and 89.1 per cent Ni(II).
358

Evaluation of heavy metals in soil : a case study of platinum tailing dam site

Nkobane, Molebogeng Precious 09 1900 (has links)
Mining industry has been identified as the main sustenance of the South African economy, however the negative impacts of the industry on the ecological systems cannot be over emphasized due to the released waste which is mostly heavy metals into the environment. The study evaluated six heavy metal (A1, Cu, Fe, Ni, Pb and Cr) contents in a tailings dam from a specific mine site. Two sets of samples for the investigation were measured, that is, one in year 2012 and the other in year 2013. In the year 2012, the sample set was only taken at a distance profile of 500 meters from the foot of the dam, whereas the sample set taken in the year 2013 was for the 500 and 1500 meter distance profiles from the foot of the dam. The year 2012 and 2013 sample sets for the 500m distance profile were sampled very similarly to each other. A kilogram of each sample was taken as per grid format. The samples at varied depths were taken at 0-cm depth for the top layer, 20cm depth for the second layer, and 30cm depth for the third layer. The samples for the surface varied distance were taken at 1 m, 2m, 3m, and 4m away from each 500m and 1500 sampling points. The 2012 samples were analysed using characterization methods namely ICP MS and The 2013 samples were analysed using the ICP OES. The comparison of the field results for the six heavy metals studied (A1, Fe, Pb, Cu, Ni and Cr) was performed using statistical analytical methods, namely ANOVA. The statistical analysis results for heavy metals (A1, Fe, Pb, Cu, Ni and Cr) from sample and 2013 revealed that the group means are not significantly different from each other which means that there is no significant difference in (A1, Fe, Pb, Cu, Ni and Cr) concentrations with respect to both depth and distance. The observations from both 2012 and 2013 indicate the results of the samples are in agreement. In addition, the comparative average concentrations of the three results obtained reach the same conclusion that the tailing dam probably does not introduce considerable or significant amounts of these metals (A1, Fe, Pb, Cu, Ni and Cr) into the surrounding soils. / Chemical Engineering / M. Tech. (Chemical Engineering)
359

Mouthpart deformities of Chironomid larvae as an indicator of heavy metal polluted water

Lindström Jonsson, Tim January 2019 (has links)
Freshwater ecosystems are under increasing pressure from a variety of contaminants, including heavy metals from mining operations, which can have complex effects that are difficult to evaluate. To detect early warnings from elevated concentrations of metals, organisms are sought to be used as monitoring tools. For example, mouthpart deformities in Chironomid larvae have been proposed as a bioindicator of stress in aquatic environments. However, the frequency and cause of these deformations, and their sensitivity to different stressors remain uncertain. In this study, I evaluated the usefulness of mouthpart deformities as a tool to monitor the effects of heavy metals from mining in northern Sweden. To do this, the mouthparts of 3789 Chironomid individuals analyzed from 17 sites closely located to mining operations and tested against concentrations of metals and DOC in the water chemistry of lakes and rivers. The frequency of deformities ranged from 0.00 – 4.79 % across all sites. Metal concentrations ranged from ‘very low’ to ‘low’ based on biological effect risk assessments. Of these, copper (R2 = 0.73) and cobalt (R2 = 0.66) were found to be significantly correlated with frequency of deformities. Additionally, the occurrence of deformities declined with DOC concentration, this was a nonlinear relationship. Frequencies of deformities observed in this study were lower than what have been reported to similar studies. The result from this study, together with other studies, suggest that deformities in Chironomid larvae are sensitive to even low levels of certain metals and could potentially be a good biomonitoring tool for early warnings of contamination in freshwater environments.
360

Passive treatment of acid mine drainage through permeable concrete and organic filtration

Zaal, Steven Michael January 2016 (has links)
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering, 2016 / The aim of this research was to reduce heavy metal and sulfate content of acid mine drainage (AMD) through the methods of passive filtration by combining permeable concrete and organic materials. This was to achieve a low cost, yet effective temporary treatment method for rural/poor communities who are affected by AMD. The acids are filtered through layers of alternating pervious concrete and biological composting layers. The concrete layers target removal of heavy metals such as iron, manganese, potassium, and magnesium, etc. through precipitation as well as reduce sulfate content to a small degree along with total dissolved solids. The concrete layers also aid in raising the pH of the AMD to more acceptable levels. The biological layers achieve sulfate remediation through the metabolism of sulfatereducing- bacteria (SRB). This process however required time and the organic layers were thus thicker and less permeable than the concrete layers in order to allow seepage to take place at a reduced rate. A wide variation of composting layers were tested, including cow manure, chicken manure, sawdust, straw, zoo manure, and leaf compost to find an optimum mix of materials which allows for the greatest sulfate reduction through sulfate reducing bacteria in the shortest possible time. Short as well as Long-term testing of rigs was undertaken to establish effectiveness, limitations and lifespan of the filtration systems. AMD from a mine in the Mpumalanga coal fields with exceptionally high sulfate content was used to test effectiveness of the organic materials over a short period of time. With long term testing conducted with a synthetic AMD, due to limited supply from the mine. The short term testing yielded removal of sulfates in the order of 56% when using kraal manure as the biological reagent mixed with sawdust for added organic carbon. The mix percentages by volume were 80%Sawdust to 20%manure and this setup was able to achieve the 56% removal of sulfates within 14 days. The filter also successfully raised the pH to 8 while removing a significant portion of heavy metals. The long term tests showed complete (100%) remediation of sulfates after a period of approximately sixty days. The tests are continuing to determine their finite lifespan and limitations. The results show promise for using the technology as a low cost, temporary measure to protect locally impacted groundwater, especially for isolated and/or rural communities while a permanent long term solution is sought.

Page generated in 0.0307 seconds