Abstracts of Undergraduates Dissertations-UWU

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Adsorption of Lead (Ii) Ions Using Chemically Modified Banana Stem Fibers as a Low Cost Adsorbent
(Uva Wellassa University of Sri Lanka, 2017) Shakoor, I.F.
Sorption of Lead (II) ions from aqueous solution on to banana stem fibers modified with citric acid treatment were investigated with respect to pH, contact time, initial metal ion concentration, adsorbent dosage, agitation speed and particle size which are the factors that affect the adsorptive capacity. Effects of different citric acid concentrations on the modification of banana stem fibers were also determined in this study. Adsorption was found to be effective, which was 99.5% at an optimum pH of 4.5, where, the initial concentration used was 2 ppm. It took 90 minutes of contact time to achieve equilibrium with an effective agitation speed of 180 rpm. The effective particle size and the adsorbent dosage were found to be below 63 um and 3.0 g respectively. Citric acid concentration used in the modification was also found to be an important factor which affects the adsorption capacity. Final Lead (II) ions concentrations were measured by using Atomic adsorption spectrophotometer. FT-IR analysis showed that banana stem fibers consist of functional groups such as hydroxyl and carboxylic groups which play a major role in the adsorption process. It was observed that with the citric acid modification the peaks' intensity was a little higher compared to that of unmodified banana stem fibers. Langmuir isotherm model fitted well with the results obtained with a R2 value of 0.992 and qmax of 20.12 mg g-1, while Freundlich isotherm model did not describe the process well. Regeneration capability of used banana stem fibers for the re-utilization was found out to 'be very effective under desorption studies carried out where, HC1 concentration was kept constant while varying the contact time. The optimum desorption results obtained was approximately 85% in 90 minutes of contact time in 0.1 M HC1. The results obtained from the study suggests that banana stem fibers modified with citric acid can be used as an effective low cost, eco-friendly adsorbent for the removal of Lead (II) ions from aqueous solution compared to unmodified banana stem fibers.
Analysis of Fate of Septic Tank Le Chate S
(Uva Wellassa University of Sri Lanka, 2013) Gowrinath, P.
Well water is an important water source, which provides drinking water supply especially to dry zone of Sri Lanka. Therefore, considering in the quality of groundwater is essential to ensure the health of human and other living things. However, the quality of groundwater varies place to place, mainly depending on its geological origin, even though it is become deteriorated by various anthropogenic activities. This is especially due to population increases and subsequent poor sanitary facilities by means of poorly design a toilet pit Nowadays in Sri Lanka. In this context, this study was concerned on the influence of toilet pits on the groundwater quality in Vavuniya town area. Study was focused Vavuniya urban area in which 60 wells were randomly selected and samples were obtained for the water quality analysis. In which the well samples were tested for the nitrate (NO3"), Phosphate (P043") and the fecal coliform count and the distance between well and toilet pits were measured. The relationship between the quality of groundwater and distance to toilet pit was analyzed on MINITAB 14.0 statistical kit. It has been found that the increased number of poorly designed toilet pits are one of the factors causing nitrate and phosphate contamination in its adjacent wells. In the study area the nitrate concentration shows the significant variation from 1.74 to 172.75. Nearly 17% of the well are exceed the maximum permissible limit and consider as not suitable for drinking purposes. Most of the wells are under the suitable condition for drinking purposes, which have the nitrate concentration below 45 ppm; but nearly 10% of the wells are very close to the maximum permissible limit these wells have the susceptibility to exceed the maximum permissible limit in few years. Mean nitrate concentration values of this area wells is above 30.98 ppm. The phosphate concentration not show the huge variation and most of the wells fall into the maximum permissible limit so it rarely causes the water quality problems. In Vavuniya urban area we have to take the immediate measures to prevent the further contamination. Furthermore, the nitrate concentration further increases with the number of toilet pit if the number of toilet pits high the concentration also high So that it is found that the toilet pit is one of the reasons for the nitrate contamination in well water.
Analyzing Seasonal Variation of Water Quality Parameters of Kelani River
(Uva Wellassa University of Sri Lanka, 2017) RANATHISSA, N. P.K.
Raw water quality of a surface water body directly affects the purification process and the final water quality of drinking water. When considering Sri Lanka, the Kelani River plays a vital role in fulfilling people's water necessities, as it provides water for more than 80% of the population of capital city, Colombo. The current study focused on the Kelani River in order to identify the models of variation of raw water quality parameters and to investigate patterns and trends of parameter variation. The main objective was to forecast the variation of water quality parameters with special reference to the Kelani River. The water quality was analyzed with different parameters including pH, Turbidity, Electrical conductivity, Total Coliform and Escherichia coli, and used data that was gathered for five years (2012-2017) at five different intakes. Analysis was carried out by R studio software. Time Series techniques were used to perform the tests, and all decisions were made under p-value of 0.05. ARIMA and SARIMA models were used to identify the best fitting model for the variation of quality parameters with time. Results were forecasted for a 6 month time period using the above fitted models. Based on obtained results, the seasonality of the water quality parameters changed from one intake to another. When analyzing the pH, Ambathale and Biyagama showed seasonality while other three intakes showed non seasonality. Electrical Conductivity had a seasonal variation at Biyagama and Pugoda intakes, while Escherichia colishowed seasonality for Ambathale intake only. Frequent long-term monitoring of physicochemical parameters of surface water resources is vital for the better management of water resources as well as aquatic habitats and the environment. Based on the results of this study, a better prior understanding about the behavior of raw water quality parameters can be obtained, and this prior understanding can be used to manage the water purification process and final water quality. Keywords: Kelani River, Water Quality, Time Series Analysis, ARIMA, SARIMA
Arsenic Removal from Water Using Humic Acid Modified Meetiyagoda Kaolinite
(Uva Wellassa University of Sri Lanka, 2013) Jayahansani, K.H.D.
Kaolinite is one of the major clay types which can be used to remove ions from the water by using its adsorption capacity. Though Sri Lanka is blessed with several clay types, none of them are used for value addition purposes. By considering that fact and the unique ability which possesses by kaolinite to remove ions from water when it is in contact with water is focused throughout this research. Meetiyagoda kaolinite is used as clay type, because it is currently used only as a raw material for ceramic industry as well as none of the researches has been conducted to identify its ability to remove ions from water. Thus, the ultimate goal of this research is to fill up that gap and to develop a value added product from Meetiyagoda kaolinite. Throughout this research it focused on removing Arsenic (V) from water while modifying kaolinite surface using Humic Acid in order to enhance the adsorption capacity of kaolinite and measuring the removal amount of arsenic (V) by changing amount of clay, concentration of arsenic (V) and pH. With increasing of arsenic concentration, arsenic adsorption on to humic acid modified Meetiyagoda kaolinite has increased whereas increasing of amount of humic acid modified Meetiyagoda kaolinite in solution, the adsorption has decreased. The highest sorption has gained when pH was in 6.0.
Biocoagulation and its Potential Applications for Graphite Bioprocessing
(Uva Wellassa University of Sri Lanka, 2013) Jayarathna, S.P.B.L.
The technical relevant sorting processes like density, magnetic or electrical separation and flotation, require a narrow particle-size range for a sufficient selectivity in order to eliminate overlapping effects. Since the rapid decrease of the mass forces and increase of the surface energetic state with decreasing particle size the well-known sorting processes are not applicable to an effective separation of particle sizes smaller than 10 mm. Flotation cell is common in Graphite industry to upgrade its carbon grade and it used to upgrade over 80 % Graphite in Sri Lanka. Pyrite is a major impurity in Sri Lankan Graphite and it remove as lumps with graphite. Three fungi were isolated from Bogola graphite mine and Saccharomyces cerevisiae was used to biocoagulation process. Isolated fungi were named as Fl, F2 and F3. Ash content was analyzed to determine the carbon grade of graphite. Furthermore, biocoagulation was tested to 40 pm, 56 p,m and 72 pm particle sizes. All three fungi Fl, F2 and F3 were given over 99% carbon recovery grades. Among them, highest carbon recovery grade obtained from F1 fungus. The efficiency of biocoagulation decrease with the increment of particle size and maximum coagulation was observed in 40 pm. Key Words: Graphite, Biocoagulation, Fungi
The Biological Treatment for Color Removal of Distillery Effluent
(Uva Wellassa University of Sri Lanka, 2013) Dilini, L.M.L.
Distillery effluents should treat before disposal into the environment.Spent wash is the major polluting waste of distillery industry.These effuents may cause severe soil and water pollution, specially in aquatic environments. It reduces the sunlight penetration causing decreased photosynthetic activities. Various studies have been carried out on removing these effluents from the water bodies, using physical and chemical methods. But these methods are very hard,could be very expensive and could be destructive to the environment. In this study we used biological method to remove these effluents from aquatic systems which is more economical and environmentally friendly. In this study we planned to remove the colour by using five polyporus fungal species that is commonly found inMatara area. Basidiomycetes decomposing fungi has exhibited extensive bioremediation activities that are mainly based upon their capabilities to produce one or more extracellular lignin-modifying enzymes which have thepotential to decolorize distillery effluent.In this study over the fivepolypores fungal species were collected and cultured. The absorbance was mesuared for seven days, after 5 days incubation period. Results revealed that most of fungal species were removed up to 50% of color.The most efficient color reducing fungal species was fungal "C" (Lenzites botulin). Key words: Polyporusfungal, spread plate; streak plate, ligninolitic enzymes, liquid broth
Characterization of in-situ Corundum Occurrences in Sri Lanka: A case study from Badalkumbura, Sri Lanka
(Uva Wellassa University of Sri Lanka, 2014) Chathuranga, H.P.G.
Gem deposits can be categorized as primary or in-situ deposits and secondary or sedimentary deposits. All Sri Lankan gem deposits are belonged to one of these gem deposit types. The primary gem deposits are metamorphic deposits and magmatic deposits (Chandrajith & Dissanayake, 2010). According to the Dahanayake et al, 1980 there are three major secondary gem deposit types recognized as alluvial, eluvial and residual in our country. This research is carried out to study the corundum mineralization and to identify primary and secondary deposits in the Badalkumbura area. Primary and secondary samples were collected from Badalkumbura area. petrologcal analysis were carried out using primary fresh rock sample and XRF analysis were done for geochemical analysis of residual soil samples.' Sedimentlogical analyses were carried out for river sediments. Corundum mineral were identified in thin section during the petrological analysis of primary rock samples. According to XRF analysis results A1203 was identified and Ti, Fe were identified as trace element. According to analysis secondary, residual and rock samples the major sources for the gem mineralisation are garnet-sillimanite—graphite-gneiss (khondalite) and skarns. Weathering of source rocks and transportation though the tributaries have formed the secondary gem deposits in law land areas. Further sedimentological analysis interpreted the low distance transportation of these sediments from the source.
Determination of Heavy Metal Speciation in Kandy Lake and Surrounding Water Resources
(Uva Wellassa University of Sri Lanka, 2014) Vinayahamuththurasa, S.
These days chronic toxicity of heavy metals is becoming potential impact on human as well as the aquatic animal. To get the clear understanding of chronic toxicity it is important to study the metal speciation as its divalent ion can be present as a variety of aqueous species, including the free cation, inorganic or organic complexes. So aim of this study was to determine the metal speciation in Kandy Lake and some near water ways around the Lake in order to predict the chronic toxicity for the aquatic organisms as they are more sensitive for elevated concentration of metal. The work was done through the geochemical model called Visual MINTEQ 3.0. The results of this study were shown that metal speciation depends on various factor such as pH, dissolved organic matter and total metal concentration. High pH would reduce the bioavailability of heavy metal. Inorganic and organic complexes would also decrease bioavailability of metal at high pH. 0.5n/1 Cd was found only in intake water for water purification plant and also it showed high Zn concentration as 1776.6 µg/l. It was found that particular point called intake water for water purification plant may have chronic toxicity of metals such as Zn" 1546.4 [tg/1 and Cd" 0.46 p,g/l. So it may be harmful to aquatic organisms such as Rainbow trout and green alga as their toxic exposure for Zinc was identified as 110-1970 pg/L and 26-1630 vtg/L respectively, while Pb, Ni, Cu have significant level. The Kandy Lake and outgoing canals did not show any chronic toxicity. Inlets showed averagely 0.4[ig/1 0.0714/1 Cu" and 6.1p,g/1 Zn". Kandy Lake showed averagely 0.2[1g/1 Ni", 0.005[1g/1 Cu" and 1.4[1g/1 Zn2+ while outgoing canal showed averagely 0.511g/1 0.08m/1 Cu" and 5.6pg/1 Zn'. At this Moment no any chronic toxicity in lake, canal and river except the point called intake water for water purification plant.
Determination of the Most Effective Size of Moving Beds for "Mbbr" System
(Uva Wellassa University of Sri Lanka, 2014) Bandara, H.W.M.N.
MBBR is Moving Bed Biofilm Reactor. This is the modern technology of waste water treatment in world. This biological process is used for waste water treatment both municipally and industrially for BOD removal, nitrification and de-nitrification. MBBR consists of a tank with submerged but floating plastic (usually HDPE, polyethylene, polypropylene) media having specific gravity less than 1.0. The large surface area of the plastics provide abundant surface for bacterial growth. Biomass grows on the surface as a thin film whose thickness usually varies between 50-300 microns. Medium or coarse bubble diffusers uniformly placed at the bottom of the reactor maintains a dissolved oxygen concentration higher than the 2.5-3 mg/L for BOD removal. Higher DO concentration is maintained for nitrification. To retain the media flowing out of the tank, screens are placed on the downstream walls. A clarifier or a DAF is placed downstream of the MBBR tank to separate the biomass and the solids from the waste water. Sludge recycle is not required for this process. There are several sizes of moving bed. These sizes are indicated as PE01, PE02, PE03, PE04, PEO5 etc. This research is done for determination of the most effective size of moving bed for reducing COD in dye waste water.
Determine the Presence of Gold and its distribution in Upper Nilwala River Basin, Southern part of Sri Lanka.
(Uva Wellassa University of Sri Lanka, 2014) Saranga, B.G.P.T.
Gold (Au) is a native metal has a higher value for it. Investments made on gold prospecting are only second to oil exploration. Billions and Billions of rupees will be spent for the soil analysis done for gold prospecting. This research was carried out to find gold in upper Nilwala River and possible areas that gold can be found. In this study, distributions of indicator elements of gold were studied to identify potential gold enrichments in the upper Nilwala River Basin. 30 samples of river sediments and 10 samples of gem pit sediments were collected within upper Nilwala River Basin. These samples were prepared to carry out mineralogical analysis and XRF analysis. Then the data was interpreted find out the distribution of the gold. Within 40 gem pit samples and river sediment samples, gold was able to find in NWM-10 location by mineralogical analysis. Using XRF analysis gold was able to find in NW-2, NW-8, NWM-4, NWM-8 and NWM-10 locations. As, Pb, Co, Ni and Cu indicator elements and pyrite grains were used to identify possible areas that can find gold. According to it NW-23, NWM-2, NWM-5, NWM-6 and NWM-9 locations were identified as possible areas that we can find gold. This study reveals, gold is present in the upper Nilwala River Basin. Mainly these gold particles can be found in the gem pits so there is a higher possibility to find gold in gem pits sediments than river sediments.
Developing a Stratigraphical Model for Gem bearing Alluvial Basin at Rathnapura, South Central Sri Lanka
(Uva Wellassa University of Sri Lanka, 2014) Pradeep, N.T.R.
The Rathnapura gem field consist of Pleistocene or sub-recent alluvium with patches of streak of gravel of heavy minerals laid down in flood plains of streams, either in the beds of abandoned tributaries or talus fans at the foot of steep hill slopes. The heavy minerals including gems were deposited during periods of intense flooding that caused their mechanical removal from their source areas. Alluvial over lied fills materials generated from abrupt and episodic events such as landslides and flooding in periods of intensified monsoonal activity. Therefore the features of the alluvial sediments present as a clue for the environmental condition at the time they were deposited. The processes such as erosion, transportation and deposition responsible for the sediments reflect the region's environmental history. Gem pits located at Pelmadulla which is one of the major gem Mining cities of Sabaragamuwa province, was selected for this study after an extensive desk evaluation. Gemming areas at Pelmadulla are located in a broad alluvial plain that is surrounded by ring of mountains. The alluvial plain is utilized for paddy cultivation. Alluvial plains is presently in the both side of Pelmadulla to Lellopitiya (Sannasgama)are being mined for gems. Study was conducted on 47 separate gem pits from Lellopitiya to Pelmadulla order to construct the alluvial serigraphy. These selected gem pits have not been disturbed by previous mining and have natural alluvial stratigraphy. Coordinates of the geril pits, the existing stratigraphy, depth of the whole alluvial section and sub units were recorded in the field. Then, these information were used to construct a three dimentional modal for this sedimentary basin. Interpolation, one of commonly used geostatistical tools in basin analyses, was employed to generate the modal from collected data. Arc GIS 9.3 and Surfer 11 softwares were used to interpolation and mapping steps of the study. Constructed model of the gem bearing layer interpretes the deviation of the drainage pattern time to time due to weathering and erosion of the bed rock.
Development of Efficient Method for Hardness Removal from Groundwater
(Uva Wellassa University of Sri Lanka, 2013) Anuruddha, I.G.G.U.
One of the factors that establish the quality of a water supply is its degree of hardness. The hardness of water is defined in terms of its content of calcium and magnesium ions. Since an analysis does not distinguish between Ca2+ and Mgt, and hardness is induced due to by carbonate deposits in the earth. They have tendency to make water unusable for industrial and domestic purposes .Therefore it is necessary to formulate a mechanism to remove total hardness in utilizing water. Bentonite enormously abundant, because of huge industrial usage. It has been considered as a potential absorbent for removing pollutant from water and waste water. The effective application of bentonite for water treatment is limited due to small surface area leading to its low adsorption capacity. Therefore, this research is focused to change the surface area to obtain maximum adsorption capacity and hence remove the hardness in the water. To achieve this aim, bentonite was treated in varying concentrations of hydrochloric acid, potassium dihydrophosphate and sodium sulphate. Then the hard water was passed through the treated bentonite clay and measured hardness via EDTA titration method. In that case 0.5 M HC1 treated Bentonite has removed 60.4 % of hardness and 150 mg/L KH2PO4 treated bentonite has removed 66.1% and as well as 150 mg/L Na2SO4 treated bentonite has removed 71.0% of hardness in 20 mL of hard water sample. Changes within the surface area are the dominant factor for the final outcome. It was clear that treated bentonite can remove total hardness than the raw bentonite.
Development of Microbial Combination to Extract Fe2+ from Ilmenite
(Uva Wellassa University of Sri Lanka, 2014) Kajaruban, N.
Value addition through ilmenite upgrading for the production of pure rutile (Ti02) can be a gainful utilization of titanium bearing mineral resources of Sri Lanka. Therefore this research aims to extract Rutile from Ilmenite using microorganisms and it will be more efficient and cost effective method to convert ilmenite to rutile in Sri Lanka by using locally available raw materials. Bioleaching has been suggested as an alternative to traditional mining techniques in extraterrestrial environments. This study was a continuous of the previous study of "The Use of Microorganism in the Process of Extracting Rutile from Ilmenite" by Wijepala Abeysinghe Mudiyanselage Asanka Nuvansiri Illankoon. Previous study has proved the leaching mechanism of the particular microorganisms on ilmenite. But the previous study had tried only the individual microbial leaching process. In this study, it was focused to find the best microbial combinations to dissolve Fe2+ from ilmenite. The biological leaching experiments were conducted using bacteria, fungi and biofilms. Those Microorganisms, which were taken from Pulmudai beach area and isolated and both strains were able to grow in the PD and NA media (Previous study). From the previous study best iron leaching fungi (F2) and two best iron leaching bacteria (B5 & B6) were selected for this study. By using the different combinations of B5,B6 and F1, three types of biofilms were formed. Then All the individual types and the combinations of the above microbes were inoculated to the ilmenite samples and iron leaching amount was weekly measured by AAS for consecutive seven weeks. According to the AAS results F I individual fungi strain has leached more iron than other types. Though the combinations (Biofilms) have failed to reach the best efficiency level they have beat the B6 individual bacteria type. Finally all the microbial inoculated mediums were increased their pH values than their initial pH. That implies the microorganisms are directly contributed for the increasing of the iron leaching rate in ilmenite.
Differentiate Quartzite and Vein Quartz from the Bedrock by Resistivity Method
(Uva Wellassa University of Sri Lanka, 2013) Weerasekara, W.M.M.A.
Previous studies reveals that the resistivity response for vein quartz is unique, reflects a flat nature of 1D resistivity curves in Vertical Electrical Sounding (VES), though both the bedrock and vein quartz are in same dynamic range of resistivity values. Almost same characters are observed in quartzite as similar to the vein quartz and this study intended to use the resistivity response as a tool to identify quartzite from other types of bedrock(s). Resistivity data acquired during a survey in Mahakirula survey site, Kahalla-Pallekale area as a preliminary study of irrigation scheme, was considered for this analysis. Over 12 VES soundings were conducted at Mahakirula site with 200m line extent and over 40m depth detection limit. The outcome of the resistivity survey has been confirmed via drilling and quartzite appeared as the bedrock at many locations. The 1D Vertical Electrical Sounding (VES) curves that of quartzite terrain(s) in Mahakirula reflect a flat response where quartzite beds are present. Similar 1D response is displays for quartzite as of the vein quartz and differs from the bedrocks. Therefore the same resistivity technique procedure which used to identify the Vein Quartz from the bedrock can apply to the Quartzite to differentiate from its associated bed rock. Key words — 1D Resistivity, Vein quartz, Quartzite, Vertical Electrical Sounding (VES)
Economically Effective Treatment Method to Improve the Quality of Effluent of Small Scale Vehicle Service Stations
(Uva Wellassa University of Sri Lanka, 2014) Rangana, J.A.T.
Vehicle service stations are considerable waste water generators which are now increasing rapidly in number all around the world. In Sri Lanka, the treatment plants operating in these service stations functioning poorly .Specially the service stations located in the rural areas have very poor treatment methods. Present study carried out to introduce a low cost and effective simple treatment method to the effluent of small scale service stations. In the study, characterized homogenized effluent sample collected from small scale service station was passed through Slow Sand Filter which is constructed by using sand, burnet brick clay & partially burnt rice husk. Then filtered samples were analyzed for the parameters of Chemical Oxygen Demand (COD),Biological Oxygen demand(BOD), oil and grease,Turbidity and lead concentration. Filters were operated for three different flow rates in replicates. • Selected flow rates for the study are 0.69 ml/min., and 16.67m1/min. Percentage removal of oil and grease, lead and percentage reduction of COD were calculated for each flow rate. Resulted reduction percentage of above parameters was grater at the flow rate of 0.69m1/min compare to other flow rates. Reduction percentage of COD,BOD, Oil & Grease, Turbidity and Lead are 64 %, 67.75% , 87.06% ,76.47% and 98.7%respectively. Also, results indicate that flow rate is a key parameter effect on parentage removal of Oil & Grease and Lead. Father studies are required to optimize the flow rate for maximum removal of Oil & Grease and Lead from the effluent. KEYWORDS: Treatment of service station effluent, partially burnt rice husk as a filter media, slow sand filter.
Effect of Low ph of Groundwater in Rathupaswala Area, Sri Lanka: a Case Study
(Uva Wellassa University of Sri Lanka, 2014) Premalai, W.A.V.
Groundwater occurs in different type of aquifers under various geological conditions. Sri Lanka has a centrifugal pattern of groundwater movements which effectively controlled by the geomorphological characteristics of the terrain. This study is focus to Rathupaswala area in the western province which was highly controversial during the past due to low pH groundwater. The area is covered within Attanagalla basin which has dendritic drainage pattern. The lateritic aquifer system is common in the study area consisting of hard and soft laterite soil which is usually considered as a very good filter media for groundwater. The research is mainly aim to identify the mobility of selected trace elements (Fe, Mn, Cr, Zn, Cs, Sr, Rb, and Li) into the groundwater under prevailing low pH condition and to identify the water type of the area using selected major cations (Na, K.+, Ca', me) and anions (S042-, Cl-, CO32: and HCO3- ) to investigate possible geochemical processes that can be take place under natural low pH. Thirty (30) selected groundwater samples were collected from the shallow and deep wells and in-situ measurements of pH, Oxidation Reduction Potential (ORP), conductivity and turbidity were done just after collecting of the samples. Selected cations were analyzed using Atomic Absorption Spectrometer (AAS). In addition, sulfate analysis were done using nephelometer. Conversely element chloride, carbonate and bicarbonate were analyzed using respective titration methods. Multivariate statistical analyses were used to determine the correlations between the elements and the physiochemical properties by means of minitabl4 software. Average values of cations and anions and the physiochemical parameters indicate that lower effects on groundwater in the area. Results further show that strong positive relationship between Mg-Mn, Li-Rb and Na-K. Significant strong positive relationship between K-Mn. Positive relationships between Na-Mn and Na-Mg. Correlations between those elements may reflect the weathering evidences of ferromagnesian minerals available in the basement. However, pH show negative relationship with Na, K, and Mg. This may reflect lack of sulfide bearing minerals with ferromagnesian minerals which usually help to create acidic pH for soil and water. This concluded that the lower pH is not due to mineral weathering in the basement in the area. Other elements such as Ca, Mn, Fe, Cu, Zn, iii Li, Sr, Cs, Rb, chloride, sulphate and bicarbonate show very poor trends with pH. This further reflect possible evidences for lower impacts of mineral weathering on low pH groundwater. Conductivity shows positive relationships with Na, K, Mg and Mn which reflect salinity of groundwater is controlled from those elements and they considered as basic cations which help to buffer the lower pH. Only calcium shows stronger positive relationship with turbidity may be due to calcium carbonate sources. In general, it can be concluded that lower pH groundwater in the area is not directly associate with mineral weathering phases in the basement rocks. Piper classification is used to determine the available water type. The classification indicate that the Na-bicarbonate water (51.6%) as the major water type present in the area and Ca-Na-bicarbonate (35.5%) type water is also dominantly present. In addition, few samples from the area reflect high concentration of Mn. Key words — Groundwater, Low pH, Trace element, Piper plot, Correlations
Effect of Water Chemistry on in -Situ Deposition of Kandy South Water Treatment Plant
(Uva Wellassa University of Sri Lanka, 2013) Saumyarathna, N.G.R.
The Kandy Sauth Water Treatment Plant (KSWTP) was commissioned on 29th January 2010. The main responsibility of this plant is to treat raw water abstracted from the Mahaweli Ganga (River) and supply the treated water to 15 reservoirs located in the service area, i.e. south to the Kandy Metropolitan area. This plant is designed to produce 35,000 m3/day of drinking water compiling to the SLS standards. The possible effect of water chemistry on in-situ deposition of Kandy South Water Treatment Plant has been analyzed in this study. Brownish black color depositions are found on the inside of the casing, impellers and also on the surface of the moving parts of the Non Return Valves (NRV"s) at KSWTP. Water in the channel at the service outlet of instrument is black color. It is also noticed that black—brown color deposition on walls of clear water reservoir. Deposit samples were analyzed using EDX (Energy Dispersive X-ray fluorescence) method. Wet samples were analyzed to determine the bacteriological effect of manganese deposition. Chemical water quality parameters were analyzed using various analytical methods. Major and minor ions were measured using titrimetric and spectroscopic methods using Varian SpectrAA 240 AAS available at the Uva Wellassa University and as atomic Hatch DR 5000 as UV/Vis spectrophotometer. Other physical properties were measured with standard methods. Deposition results when dissolved ions in the water such as iron, manganese an4 copper exceed the solubility of a given mineral. Several principal factors determine deposits forming such as temperature, pH value, amount of deposit-forming material present, and influence of other dissolved materials. Manganese oxidizing bacteria analyzed data shows that there is not any biological manganese oxidation process in this water treatment process. Source of Iron and manganese of the water is raw water. There is no copper in raw water. Ferrihydrite, Ferrihydrite (aged), Gibbsite (C), Goethite, Hematite, Lepidocrocite, Strengite, Fe(OH)2.7C13(s), Maghemite Magnetite are the main possible mineral phases which are formed iron oxide. MnHPO4(s) is the only mineral phase which forms the manganese oxide and cuprispinl is the only mineral phase which forms the Copper. Deposit samples show high content of Manganese, Iron, and Copper.
Enhance the Coating Proces of apatite on Metals
(Uva Wellassa University of Sri Lanka, 2013) KUMARA, J.A.S.P.
Primarily all metallic surfaces are susceptibility to degradation when they are exposed to the environment. Therefore metallic properties of the surfaces are rapidly changed. Several factors affect the surface corrosion like, 02 concentration, moisture content, salt concentration etc. Hence, applying the anti-corrosion coating to metallic surfacesis more influential to protect it from degradation. An anticorrosion property of apatite is utilized to prevent such surfaces. This is and value added application of apatite apart from its usage as a fertilizer. In the present situation, powder coating of apatite utilized to prevent the metal surfaces. But the whole process consists of many high cost activities. As an innovation, the cost of product becomes higher respect to the other anticorrosion coatings present in the market. However, any deprival is not happening to the property of anticorrosion of the apatite within whole process. This researchfocused to make an anticorrosion coat using apatite which is easier to handle, environmental friendly (as it) and cost effective compared to the products available at the market. Initially pure apatite crystals were ground and sieved in to size less than75/imusing the sand grinder and sieve set. Then powder was mixed withother components in standard ratios which were decided after several experiments and final anticorrosive lacquer was produced. Then the anticorrosion property of each sample was tested in three ways compare with a higher selling anticorrosive lacquer in the market. These three methods arevisualobservation;microscopic observation and study of Fe ion (by metal dipped in stimulated corrosion media)release usingAAS. Experiments were repeated with changed corrosion media. Comparing the results of microscopic observations of corrosion spots and amount of Fe release in to the corrosion media in a constant time period in both industrially available lacquer and apatite based lacquer coated samples, the best composition of apatite lacquer mixture was determined. Key words — sand grinder, anticorrosion, fluidized bed method
Enriching the Water Quality Using Natural Rocks and Minerals
(Uva Wellassa University of Sri Lanka, 2013) Nimalika, R.M.R.
The increasing of population and other development activities create pressure on available water resources in the country. Thinking alternative and feasible water sources became a valuable factor meet present and future water demand. As an alternative of drinking water, people have used rain water. Rain water, distilled water and reverse osmosis water lack of minerals. The people who are missing certain minerals in drinking water face to various health effects. Minerals can be added back to mineral free water using natural rock samples. Mineral free water passed through the rock sample it has acquired many dissolved species. This study evaluated the selected minerals in the distilled water. All anions and cations ion concentrations in the dolomite (D), feldspar (F) and gypsum (G) samples studied were found to be below the national and international standard limits. All Samples are not in detectable level. The pH level 5-8.5, recommended by the Sri Lankan drinking water Quality standard. S042-and Na ion concentrations were very low compared with national and international standard limits. Dissolve ion concentration values are depending on amount of the material and pH variations. 5042- and Na ions were less soluble with pH variation. The C032- ion concentration was varying in range of 60 to156. That level was preventing hardness in water. Most suitable pH level is 7. The pH 7 samples had S042-concentration of 3.05 mg/L, recommended by the WHO drinking water Quality standard and Sri Lankan drinking water Quality standard. Total Hardness in pH 7 studied samples were 120 mg/L, recommended by the Sri Lankan drinking water Quality standard. As same as ion concentration of Na is 4.2452 mg/L, recommended by the WHO drinking water Quality standard. There are not available national and international standard limits for Ca, Mg, and K in drinking water. As a result of that cannot concluded Ca, Mg and K ions in water samples. The optimum pH condition is 7. According to results the pH 7 samples are not in detectable level. Those ion concentrations are most suitable for drinking purposes. According to the final conclusion method of the research was success for enrich water quality with natural rock samples. The study evaluates the selected macro minerals in the water commonly treated in this method and it help to prevent the occurrence of mineral toxicity due to drinking water.
Estimating the magnetite content of the Southern part of Eppawala Phosphate Deposit and its parent rock
(Uva Wellassa University of Sri Lanka, 2014) Erandi, H.P.V.H.
Phosphorus is one of most important plant nutrients because its function cannot be performed by any other nutrient. It is involved in wide range of plant processes such as young, fast growing tissues and performs a number of functions related to growth and development. So that the demand of phosphorous of fertilizer industry is mainly accomplished by phosphate rocks world wide. Sri Lanka also has such phosphate deposit at Eppawala. It is one of most economically valuable mineral deposit in Sri Lanka. Eppawala phosphate deposit, located in the Anuradhapura district of Sri Lanka, about 200 km from Colombo, was discovered in 1971. This deposit exists as a dense weathering profile underlain by an appetite containing carbonate rock. The ore bodies at Eppawala contain up to 42% P 205, and citric acid solubility of different components varies from 4 to 6%. Owing to intense weathering of the apatite-bearing carbonate rock, a phosphate deposit has been formed by relative accumulation of the primary apatite crystals, together with the secondary products derived from them. The economically useful phosphate is a secondary formation developed over apatite-rich carbonatite parent rock. Former studies revealed that iron leached from the weathering parent rocks played an important role in fixing phosphate and formation of the secondary deposit through in-situ diagenesis. This phoscrete-type phosphate deposit has been developed on an appetite-rich carbonatite body. Source of iron is assumed to be magnetite and other iron-bearing minerals. To get grater benefits from the deposit it necessary to produce value added products such as triple super phosphates. And also Due to considerable amount of iron impurities of magnetite and other iron baring minerals, the production of super phosphate as well as direct use of phosphate rock as a fertilizer is restricted. This research has been conducted to estimate the magnetite content of Eppawala phosphate deposit, southern part. For the estimation magnetic susceptibility, thin sections of both secondary phosphate deposit and primary deposit and percentage amount of magnetite and XRF results of selected samples were used. Key words: Magnetite, Apatite deposit, carbonatite rock, Magnetic separation

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