Applied Water Science (v.3, #1)

Identification of raining clouds using a method based on optical and microphysical cloud properties from Meteosat second generation daytime and nighttime data by Mourad Lazri; Soltane Ameur; Jean Michel Brucker; Jacques Testud; Bachir Hamadache; Slimane Hameg; Fethi Ouallouche; Yacine Mohia (1-11).
A new scheme for the delineation of raining and non-raining cloud areas applicable to mid-latitudes from daytime and nighttime multispectral satellite data is developed. The technique is based on optical and microphysical cloud properties using an artificial neural network. The tests have been conducted during the rainy season of 2006/2007. The proposed algorithm uses the spectral parameters of SEVIRI (Spinning Enhanced Visible and Infrared): brightness temperature TIR10.8 and brightness temperature differences ΔTIR10.8–IR12.1, ΔTIR8.7–IR10.8, ΔTIR3.9–IR10.8 and ΔTIR3.9–WV7.3 during the nighttime and reflectances RVIS0.6, RNIR1.6, brightness temperature TIR10.8, brightness temperature difference ΔTIR8.7–IR10.8 and ΔTIR10.8–IR12.0 during the daytime. The algorithm is calibrated by instantaneous meteorological radar using multilayer perceptron. Radar provided the ‘‘ground precipitation truth’’ for training and validation. The application shows interesting and encouraging results.
Keywords: Meteorological satellite; Mediterranean climate; Properties of clouds, convective and stratiform clouds

The moment (MOM) estimators for the parameters, quantiles and confidence limits, using the general extreme value distribution for the minima, is presented towards its application in low flow frequency analysis. The procedures to compute the parameters, design events (quantiles) for several return periods and their confidence limits are shown in the paper. Two measures of goodness of fit tests are contained in the paper to compare the proposed methodology with other models in competition. A full example of application is presented in the paper to show how easy is to apply the proposed methodology.
Keywords: Low flow; Frequency analysis; Parameter estimation; Confidence limits; Method of moments

In this study, three streams—Amuta, Agbogbo and Abagbooro were examined for salinity and sodium hazards and suitability of the water for irrigational purpose. The three streams are located within areas of three different agricultural practices and land uses. Water samples from the streams were collected twice a month for 1 year. Irrigation water quality parameters assessed included pH, electrical conductivity (EC), sodium adsorption ratio (SAR), percentage sodium, permeability index and potential salinity. Water samples were analyzed using standard chemical procedures. Results of the irrigation water quality parameters studied showed that water samples from the three streams do not exhibit toxicity problem in relation to salinity and sodium hazard. Although the data obtained for the three catchment areas for pH, EC and SAR were closely related, least concentrations of these irrigation water indices were obtained for Abagbooro stream where there is secondary forest; highest concentrations were found in Agbogbo stream and moderate values were obtained for water from Amuta stream where subsistent and mechanized farming are practiced, respectively.
Keywords: Stream; Salinity; Sodium adsorption ratio; Infiltration; Permeability and toxicity

Two natural limestone samples, collected from the Campanian–Maastrichtian limestones, Tunisia, were used as adsorbents for the removal of toxic metals in aqueous systems. The results indicated that high removal efficiency could be achieved by the present natural limestones. Among the metal ions studied, Pb2+ was the most preferably removed cation because of its high affinity to calcite surface. In binary system, the presence of Cu2+ effectively depressed the sorption of Cd2+ and Zn2+. Similarly Cu2+ strongly competed with Pb2+ to limestone surface. In ternary system, the removal further decreased, but considerable amount of Pb2+ and Cu2+ still occurred regardless of the limestone sample. The same behavior was observed in quadruple system, where the selectivity sequence was Pb2+ > Cu2+ > Cd2+ > Zn2+. From these results, it was concluded that the studied limestones have the required technical specifications to be used for the removal of toxic metals from wastewaters.
Keywords: Heavy metals; Limestone; Sorption; Precipitation; Competitive effects; Wastewater

Optimization and kinetic studies on treatment of textile dye wastewater using Pleurotus floridanus by S. Sathian; G. Radha; V. Shanmugapriya; M. Rajasimman; C. Karthikeyan (41-48).
Treatment of textile dye wastewater was carried using Pleurotus floridanus in a batch reactor. Response surface methodology (RSM) was used to optimize the process parameters like pH, temperature, agitation speed and dye wastewater concentration for the decolorization of textile dye wastewater. The optimum conditions for the maximum decolorization was: pH 6.6, temperature 28.8 °C, agitation speed 183 rpm and dye wastewater concentration 1:2. From the results it was found that, the linear effect of agitation speed and initial textile dye wastewater concentration were more significant than other factors for the textile dye wastewater treatment. At these optimized conditions, the maximum decolorization and COD reduction was found to be 71.2 and 80.5 %, respectively. Kinetics of textile dye degradation process was studied by various models like first order, diffusional and Singh model. From the results it was found that the degradation follows first order model with R2 value of 0.9550.
Keywords: Decolorization; Optimization; RSM; Pleurotus floridanus ; Kinetics

Growth and nutrient removal properties of the diatoms, Chaetoceros curvisetus and C. simplex under different nitrogen sources by Panneerselvam Karthikeyan; Kuppusamy Manimaran; Pitchai Sampathkumar; Lakshmanan Rameshkumar (49-55).
To investigate the suitability of the marine diatoms, Chaetoceros curvisetus and C. simplex for the removal of macronutrients from different wastewater, the growth and nitrate-phosphate removal properties were studied with nitrate, ammonium and urea nitrogen sources. Three separate experiments were conducted using modified F/2 medium with 12.35 mg L−1 total nitrogen and 1.12 mg L−1 total phosphorous (simulating the typical concentration of nitrogen and phosphorus in secondary effluent) as growth medium. The maximum cell densities of C. curvisetus and C. simplex were 7.16 ± 0.34 × 104 cells mL−1 in $$ { ext{NO}}_{3}^{ - } $$ and 3.88 ± 0.32 × 105 cells mL−1 in urea, respectively. The maximum chlorophyll a per cell was 1.7 and 4.7 pg for C. simplex and C. curvisetus, cultured with urea and nitrate, respectively. The high protein contents of 4.7 pg cell−1 in C. simplex with urea and 19.7 pg cell−1 in C. curvisetus nitrate nitrogen sources were found. The higher cell density and protein content of both species from urea and nitrate nitrogen sources (p < 0.05) have shown that these were utilized by microalgae and were converted to protein. The C. simplex and C. curvisetus showed maximum removal efficiencies of nitrate by 97.86 and 91.62 % and phosphate by 98.5 and 100 %, respectively when urea used as nitrogen source than ammonia. The results indicated the C. simplex was more efficient than C. curvisetus and suitable for the removal of macronutrients when cultured with urea and nitrate nitrogen sources.
Keywords: Growth; Wastewater treatment; Phytoplankton; Nitrogen sources; Biochemical composition

A study of the effectiveness of sewage treatment plants in Delhi region by Sandeep Kumar Gautam; Divya Sharma; Jayant Kumar Tripathi; Saroj Ahirwar; Sudhir Kumar Singh (57-65).
This is a conventional kind of monitoring study. The objective of the study was to assess and monitor the physicochemical parameters in wastewater at inlet and outlet of sewage treatment plant (STP) and also to study the effectiveness of the STPs. The average concentration of parameters at inlet sampling site pH, electrical conductivity, total dissolved solids, are 7.16, 2,169 μS/cm, 766.06 mg/l, and major ions bicarbonate, nitrate, sulphate, phosphate, chloride, sodium, potassium, magnesium and calcium values 515.88, 4.28, 82.85, 15.17, 7.01, 23.08, 29.34, 4.14 and 84.31 mg/l. While the average concentration of these parameters, after treatment shows following values 7.47, 2,161.43 (μS/cm), 695.81, 436.52, 1.25, 99.22, 12.69, 6.83, 23.18, 29.07, 4.40 and 82.65 mg/l, respectively. Further, to check the Na % and sodium absorption ratio at inlet and outlet which 27.89 %, 0.67 and 28.19 %, 0.68, respectively, for the suitability of the wastewater. Finally, the agglomerative hierarchical clustering techniques were used to study the similarity in the sewage treatment plants. The result suggests that there is considerable improvement in the wastewater quality after treatment except at the Pappankalan and Coronation Pillar, Timarpur.
Keywords: Sewage treatment plant; Wastewater; Water quality; Pollution; Monitoring; Delhi

Concentration of ions in selected bottled water samples sold in Malaysia by Ahmad Zaharin Aris; Ryan Chuan Yang Kam; Ai Phing Lim; Sarva Mangala Praveena (67-75).
Many consumers around the world, including Malaysians, have turned to bottled water as their main source of drinking water. The aim of this study is to determine the physical and chemical properties of bottled water samples sold in Selangor, Malaysia. A total of 20 bottled water brands consisting of ‘natural mineral (NM)’ and ‘packaged drinking (PD)’ types were randomly collected and analyzed for their physical–chemical characteristics: hydrogen ion concentration (pH), electrical conductivity (EC) and total dissolved solids (TDS), selected major ions: calcium (Ca), potassium (K), magnesium (Mg) and sodium (Na), and minor trace constituents: copper (Cu) and zinc (Zn) to ascertain their suitability for human consumption. The results obtained were compared with guideline values recommended by World Health Organization (WHO) and Malaysian Ministry of Health (MMOH), respectively. It was found that all bottled water samples were in accordance with the guidelines set by WHO and MMOH except for one sample (D3) which was below the pH limit of 6.5. Both NM and PD bottled water were dominated by Na + K > Ca > Mg. Low values for EC and TDS in the bottled water samples showed that water was deficient in essential elements, likely an indication that these were removed by water treatment. Minerals like major ions were present in very low concentrations which could pose a risk to individuals who consume this water on a regular basis. Generally, the overall quality of the supplied bottled water was in accordance to standards and guidelines set by WHO and MMOH and safe for consumption.
Keywords: Bottled water; Natural mineral water; Packaged drinking water; Water quality; Major ions

The capability of Jordanian natural zeolite to remove nickel from aqueous solutions was experimentally investigated using a packed bed column. The zeolite samples were obtained from Jabal AL Aritayn in the northeast of Jordan. The effects of the initial concentration of nickel (C0), the packed bed length (L) and the zeolite grain size (Dp) on the adsorption process were considered. The finding indicated that these parameters named had a significant effect on the removal of nickel by the Jordanian zeolite. The characteristic breakthrough curves of the adsorption process were measured. The Klinkenberg model was adopted to explain the kinetic behavior of the adsorption phenomena, and we attempted to fit the packed bed experimental data to the breakthrough curve. The effective diffusivity was estimated and used to predict breakthrough curves under other adsorption conditions.
Keywords: Zeolite in Jordan; Breakthrough curves; Grain deposition; Packed bed column

Entrapment of marine microalga, Isochrysis galbana, for biosorption of Cr(III) from aqueous solution: isotherms and spectroscopic characterization by Kishore Kumar Kadimpati; Krishna Prasad Mondithoka; Sarada Bheemaraju; Venkata Ramachandra Murthy Challa (85-92).
Microalga, Isochrysis galbana, biomass was entrapped into alginate gel by liquid curing method in the presence of Ca(II) ions. The biosorption of chromium(III) by the entrapped live algal biomass was studied in a batch system. The effect of initial cadmium concentration, pH, temperature and liquid and solid ratio on Cr(III) removal was investigated. The maximum experimental biosorption capacities for entrapped live algal biomass were found to be 335.27 mg Cr(III) g−1 of dry algal biomass. The kinetics of chromium biosorption was slow; approximately 75 % of biosorption took place in 2 h. The percent adsorption increased with increase in pH; pH 5 of the solution was found to favor adsorption very strongly. The equilibrium biosorption data were evaluated by Langmuir and Freundlich isotherm models, and was best described by Langmuir and Freundlich isotherms. The biosorbent was characterized and evaluated, the functional groups –OH, –COOH and C=O were involved in the biosorption process. Since binding capacity was relatively high for immobilized live algal biomass, those algal forms are to be considered as suitable biosorbent for the removal of chromium in wastewater treatment.
Keywords: Biosorption; Marine microalga; Immobilization; Isotherms; Characterization

Carbon nanotubes-blended poly(phenylene sulfone) membranes for ultrafiltration applications by D. Lawrence Arockiasamy; Javed Alam; Mansour Alhoshan (93-103).
Multi-walled carbon nanotubes (MWCNT) were carboxylated by a chemical method. Poly(phenylene sulfone) (PPSU), MWCNT and functionalized (carboxylated) MWCNT/poly(phenylene sulfone) (PPSU) blend membranes were synthesized via the phase-inversion method. The resultant membranes were then characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle. The FMWCNT blend membranes appeared to be more hydrophilic, with higher pure water flux than did the pure PPSU and MWCNT/PPSU blend membranes. It was also found that the presence of multi-walled carbon nanotubes (MWCNTs) in the blend membranes was an important factor affecting the morphology and permeation properties of the membranes. The model proteins such as trypsin (20 kDa), pepsin (35 kDa), egg albumin (45 kDa) and bovine serum albumin (69 kDa) rejection experiments were carried out under identical operational conditions employing both PPSU and blend membranes. The membranes were also subjected to the determination of molecular weight cut-off (MWCO) using different molecular weights of proteins. During trypsin ultrafiltration, PPSU/MWCNT and PPSU/FMWCNT membranes showed a slower flux decline rate than did the PPSU membrane.
Keywords: Poly(phenylene sulfone); Ultrafiltration; Carbon nanotubes; Nanocomposite; Blend membranes

Adsorptive removal of Pb(II) from aqueous solution using nano-sized hydroxyapatite by S. T. Ramesh; N. Rameshbabu; R. Gandhimathi; M. Srikanth Kumar; P. V. Nidheesh (105-113).
This study investigated the sorption of Pb(II) in aqueous solution onto hydroxyapatite (HA) surfaces. Batch experiments were carried out using synthetic HA. The effect of contact time, HA dosage, and initial pH on removal efficiency were also investigated. The adsorption equilibrium and kinetics of Pb(II) on this adsorbent were then examined at 25 °C. Kinetic data were analyzed by pseudo first, second, and intra-particle diffusion models. The sorption data were then correlated with the Langmuir, Freundlich, Halsey, and Harkins–Jura adsorption isotherm models. The optimum dose of HA for Pb(II) removal is found to be 0.12 g/l with the removal efficiency of 97.3 % at an equilibrium contact time of 1 h. It is found that the adsorption kinetics of the Pb(II) on HA follow the pseudo second-order reaction. All the isotherms fitted well for experimental data. Capacity of HA is found as 357.14 mg Pb(II)/g of HA. The Pb(II) immobilization mechanism was studied. The results indicated that HA can be used as an effective adsorbent for removal of Pb(II) from aqueous solution.
Keywords: Hydroxyapatite; Adsorption; Isotherm; Kinetics; Lead removal

Introducing leaky-well concept for stormwater quantity control in Dhaka, Bangladesh by Faisal Ahammed; Guna Alankarage Hewa; John R. Argue (115-123).
Dhaka, the capital city of Bangladesh with rapid and unplanned urbanization, is subjected to annual average rainfall of 2,076 mm. The intensity of rainfall during 10 years recurrence interval and 1 h duration of the city is 98 mm/h. The stormwater drainage systems of the city are often unable to manage peak runoff volume and hence urban flooding is common after medium to heavy rainfall events. A proposal to introduce leaky-wells using water sensitive urban design (WSUD) principles was investigated for Dhaka’s drainage network to transfer the present unsatisfactory situation into one which is sustainable. The regime in balance strategy was considered to control the stormwater for 100 years recurrence interval. We applied scaling theory to 57 years (1953–2009) daily rainfall data for the estimation of sub-daily rainfall intensity values. It was found that two leaky-wells; each with depth H = 2.0 m and diameter D = 2.0 m, in 500 m2 allotment can improve the situation. The emptying (drain) time of the proposed device is around 1.25 days, which meets the standard criterion. Groundwater table, soil hydraulic conductivity and topographic slope of Dhaka also support for installations of leaky-wells.
Keywords: Leaky-well; Water sensitive urban design; Regime in balance; Emptying time; Stormwater; Source control

A preliminary study was conducted for the removal of turbidity (TD), chemical oxygen demand (COD) and biochemical oxygen demand (BOD) from secondarily treated sewage (STS) water through the electrolytic batch mode experiments with DC power supply (12 V) up to 30 min and using a novel concept of electrode combinations of different metals. The different surface areas (40, 80, 120 and 160 cm2) of the electrodes as a function of cross-sectional area of the reactor and the effect of inter-electrode distances (2.5–10 cm) on the electrolysis of STS water were studied. This study revealed that the effluent can be effectively treated with the aluminum (Al) and iron (Fe) electrode combinations (Al–Fe and Fe–Al). The maximum removal of TD (81.51 %), COD (74.36 %) and BOD (70.86 %) was recorded with Al–Fe electrode system, while the removal of these parameters was found to be 71.11, 64.95 and 61.87 %, respectively, with Fe–Al electrode combination. The Al–Fe electrode combination had lower electrical energy consumption (2.29 kWh/m3) as compared to Fe–Al electrode combination (2.50 kWh/m3). The economic evaluation of electrodes showed that Al–Fe electrode combination was better than Fe–Al electrode combination. This revealed the superiority of aluminum as a sacrificial electrode over that of iron which can probably be attributed to better flocculation capabilities of aluminum than that of iron.
Keywords: Electrolytic process; Removal efficiency; Electrode combinations; Sewage water

Modeling sedimentation rates of Malilangwe reservoir in the south-eastern lowveld of Zimbabwe by Tatenda Dalu; Edwin Munyaradzi Tambara; Bruce Clegg; Lenin Dzibakwe Chari; Tamuka Nhiwatiwa (133-144).
Modelling the sedimentation rates using the Wallingford (2004) equations with the aid of NDVI (remote sensing) to assess land degradation was carried out for Malilangwe reservoir catchment in the south eastern lowveld of Zimbabwe. Siltation life of the reservoir was determined from rate of incoming sediment, trap efficiency and reservoir capacity using the Wallingford method. The average rainfall of the study area was about 560 mm while runoff from the catchment ranged from 0.3 mm (minimum) to 199 mm (maximum) with an overall average runoff of 50.03 mm. Results showed that the overall mean annual sediment concentration was approximately 2,400 ppm. The reservoir capacity to inflow ratio was estimated at 0.8 with a sedimentation rate of 120.1 tkm−2 year−1. Calculated probability of the dam filling is 26.8 %. Results also showed that the siltation life of the reservoir was >100 years according to the Wallingford method. The Normalised Difference Vegetation Index (NDVI) showed progressive decline (p < 0.05) of the vegetation health from 2000 to 2009. While acknowledging the limitations of techniques used, this study demonstrates in part the effectiveness of sedimentation modelling and remote sensing as a tool for the production of baseline data for assessment and monitoring levels of land degradation in the Malilangwe reservoir catchment.
Keywords: Sedimentation; NDVI; Catchment; Reservoir; Degradation

Tuticorin corporation stretches geographically from 8°43′–8°51′N latitude and 78°5′–78°10′E longitude, positioned in the East–West International sea routes on the South–East coast of India. The rapid urban developments in the past two decades of Tuticorin have caused depletion of groundwater quantity, and deterioration of quality through excessive consumption and influx of pollutants from natural and anthropogenic activities. The water samples collected in the field were analyzed for electrical conductivity, pH, total dissolved solids, major cations like calcium, magnesium, sodium, potassium, and anions SUCH AS bicarbonate, carbonate, chloride, nitrate and sulfate, in the laboratory using the standard methods given by the American Public Health Association. In order to assess the groundwater quality, 36 groundwater samples had been collected in year 2011. The geographic information system-based spatial distribution map of different major elements has been prepared using ArcGIS 9.2. The Piper plot shows that most of the groundwater samples fall in the field of Ca2+-Mg2+–Cl-SO42− and Na+-K+–Cl-HCO3 by projecting the position on the plots in the triangular field. The cation concentration indicate that 83, 39 and 22 % of the K+, Na+, Ca2+ concentrations exceed the WHO limit. As per Wilcox’s diagram and US Salinity laboratory classification, most of the groundwater samples are not suitable for irrigation due to the presence of high salinity and medium sodium hazard. Irrigation waters classified based on sodium absorption ratio, have revealed that 52 % groundwater are in general safe for irrigation, which needs treatment before use. permeability index also indicates that the groundwater samples are suitable for irrigation purpose.
Keywords: Groundwater quality; Geographic information system; Wilcox’s diagram; Permeability index; Tuticorin corporation; WHO

This study investigates existing water supply scenario, and evaluates the performance of pond sand filter (PSF) in meeting drinking water demand of Dacope Upazila in southwest coastal Bangladesh. Questionnaire survey to the villagers reveals that PSF is the major drinking water sources (38 %) of the study area followed by tubewells (30.4 %), rainwater harvesting (RWH) systems (12.6 %), ponds (10.3 %) and others (8.7 %). The spot test and laboratory analysis show that odour, colour, pH, dissolved oxygen, hardness, calcium, magnesium, nitrate, sulphate and phosphate of the PSFs water meet Bangladesh standard. The efficiency of PSF in reducing total dissolved solids (TDS) (15 %) and potassium (8.2 %) is not enough to meet the standard of 20 % PSFs for TDS and one-third PSFs for potassium. The study proves that PSF is unable to remove coliform bacteria by 100 % from highly contaminated water. Hence, disinfection should be adopted before distribution to ensure safe drinking water. Majority of the PSF’s users (80 %) are either partially satisfied or dissatisfied with the existing system. The beneficiary’s willingness to pay for drinking water technologies seems that the combination of PSF and RWH could ensure sustainable drinking water in coastal region of Bangladesh.
Keywords: Sustainable; Coastal region; PSF; RWH; Dacope; Bangladesh

Comparative biosorption of Mn(II) and Pb(II) ions on raw and oxalic acid modified maize husk: kinetic, thermodynamic and isothermal studies by Abideen Idowu Adeogun; Mopelola Abidemi Idowu; Andrew Edwin Ofudje; Sarafadeen Olateju Kareem; Sikiru Akinyeye Ahmed (167-179).
Maize husk, an abundant agricultural waste was used to prepare a biosorbent for the biosorption of Mn(II) and Pb(II) ions from aqueous solution in a batch process. Equilibrium and kinetics of biosorption of the metals ions were studied at 25 °C. The adsorbtion data were treated with common kinetic and isotherm models. The equilibrium data fitted well with Langmuir isotherm with maximum capacity of 8.52 and 7.38 mg g−1 for Mn(II) and Pb(II), respectively on raw biomass (UTCS). The capacity of 9.00 and 9.33 mg g−1 was observed for Mn(II) and Pb(II), respectively on acid modified biomass (ATCS). The study also revealed that the sorption process in both cases depend on biomass dosage, temperature, pH and initial metal ion concentration, respectively. The calculated thermodynamic parameters (∆Go, ∆Ho and ∆So) showed that the biosorption of the metal ions onto maize husk is feasible, spontaneous and exothermic in nature.
Keywords: Biosorption; Maize husk; Oxalic acid; Kinetics; Isotherms

Bioremediation of heavy metal-contaminated effluent using optimized activated sludge bacteria by Ebtesam El. Bestawy; Shacker Helmy; Hany Hussien; Mohamed Fahmy; Ranya Amer (181-192).
Removal of heavy metals from contaminated domestic-industrial effluent using eight resistant indigenous bacteria isolated from acclimatized activated sludge was investigated. Molecular identification using 16S rDNA amplification revealed that all strains were Gram-negative among which two were resistant to each of copper, cadmium and cobalt while one was resistant to each of chromium and the heavy metal mixture. They were identified as Enterobacter sp. (Cu1), Enterobacter sp. (Cu2), Stenotrophomonas sp. (Cd1), Providencia sp. (Cd2), Chryseobacterium sp. (Co1), Comamonas sp. (Co2), Ochrobactrum sp. (Cr) and Delftia sp. (M1) according to their resistance pattern. Strains Cu1, Cd1, Co2 and Cr were able to resist 275 mg Cu/l, 320 mg Cd/l, 140 mg Co/l and 29 mg Cr/l respectively. The four resistant strains were used as a mixture to remove heavy metals (elevated concentrations) and reduce the organic load of wastewater effluent. Results revealed that using the proposed activated sludge with the resistant bacterial mixture was more efficient for heavy metal removal compared to the activated sludge alone. It is therefore recommended that the proposed activated sludge system augmented with the acclimatized strains is the best choice to ensure high treatment efficiency and performance under metal stresses especially when industrial effluents are involved.
Keywords: Acclimatization; Activated sludge; Bioremediation; Domestic; Heavy metals; Industrial wastewater

The concentration of heavy metals was studied in the soil samples collected around the municipal solid waste (MSW) open dumpsite, Ariyamangalam, Tiruchirappalli, Tamilnadu to understand the heavy metal contamination due to leachate migration from an open dumping site. The dump site receives approximately 400–470 tonnes of municipal solid waste. Solid waste characterization was carried out for the fresh and old municipal solid waste to know the basic composition of solid waste which is dumped in the dumping site. The heavy metal concentration in the municipal solid waste fine fraction and soil samples were analyzed. The heavy metal concentration in the collected soil sample was found in the following order: Mn > Pb > Cu > Cd. The presence of heavy metals in soil sample indicates that there is appreciable contamination of the soil by leachate migration from an open dumping site. However, these pollutants species will continuously migrated and attenuated through the soil strata and after certain period of time they might contaminate the groundwater system if there is no action to be taken to prevent this phenomenon.
Keywords: Heavy metal; Municipal solid waste; Leachate; Open dumpsite

Batch sorption dynamics, kinetics and equilibrium studies of Cr(VI), Ni(II) and Cu(II) from aqueous phase using agricultural residues by Rajvinder Kaur; Joginder Singh; Rajshree Khare; Swaranjit Singh Cameotra; Amjad Ali (207-218).
In the present study, the agricultural residues viz., Syzygium cumini and Populus deltoides leaves powder have been used for the biosorption of Cu(II), Ni(II), and Cr(VI) from aqueous solutions. FTIR and SEM analysis of the biosorbents were performed to explore the type of functional groups available for metal binding and to study the surface morphology. Various physico-chemical parameters such as pH, adsorbent dosage, initial metal ion concentration, and equilibrium contact time were studied. Thermodynamic studies were carried out and the results demonstrated the spontaneous and endothermic nature of the biosorption process. The equilibrium data were tested using four isotherm models—Langmuir, Freundlich, Temkin and Dubinin–Radushkevich and the maximum biosorption capacities were evaluated. The Pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models were applied to study the reaction kinetics with pseudo-second order model giving the best fit (R2 = 0.99) to the experimental data.
Keywords: Syzygium cumini ; Populus deltoides ; Temkin; Dubinin–Radushkevich isotherm model; Elovich equation; Intraparticle diffusion model

This study reports physicochemical characteristics and their sources in groundwater in Thirupathur region in Tamil Nadu, India. For this purpose, groundwater samples were collected and analysed using standard methods. A wide seasonal variation was showed for the majority of the samples; higher concentration was observed in the pre-monsoon season. Concentration of fluoride was quite alarming in many locations. Groundwater is found to be dominated by Na+, Ca+, HCO3 and Cl. Gibbs plot showed the dominance of rock–water interaction. Geology of the area in comparison with the results obtained in the chemical cross plots showed the dominance of silicate weathering, with a minor contribution from the cation exchange. Other processes such as evaporation dissolution of carbonate and gypsum were proved to be ineffective. However, dissolution of fluoride minerals present in the geological formation is the major source of fluoride in groundwater.
Keywords: Physicochemical parameters; Groundwater; Thirupathur; Tamil Nadu; India

Assessments of hydrochemical quality and recharge source are critical components of sustainable groundwater resources evaluation and management, especially in complex weathered/fractured crystalline bedrock terrains. Assessment of the weathered/fractured basement aquifer of Ekiti area, SW-Nigeria was undertaken with emphasis on hydrochemical quality and stable isotope characterization of shallow groundwater system. The study approach involved field sampling and in situ measurements of physico-chemical parameters followed by hydrochemical and stable isotope analyses of the water samples. In situ measurements revealed EC value of 43–995 μS/cm (av 431.96 μS/cm) and total hardness of 31.3–295.1 mg/L. The pH of the water sample ranged from 7.0 to 8.9 (av 8.00). The concentrations of the major cations are in the order of Ca2+ > K+ > Na+ > Mg2+ with their respective average values of 33.35, 25.61, 24.91 and 8.7 mg/L respectively while that of the anions are in the order of HCO3 > Cl > SO42− > NO3 with their respective average values of 165.44, 31.85, 21.27 and 5.44 mg/L respectively. However, the results of stable isotope analyses revealed δ18O value of −4.2 to −2.1 ‰ and δD of −22.3 to −10.2 ‰, suggesting meteoric water source (recent precipitation water recharging the associated shallow basement aquifer) while the estimated deuterium excess of 6.80–11.00 ‰ (av 9.6 ‰) suggested little or no imprint of kinetic evaporation. Furthermore, the overall hydrochemical profiles revealed the main hydrochemical facies as Ca(Mg)-HCO3 (dominant) and Na(K)-HCO3 (minor) water types which can be attributed to dissolution of minerals in the various rock units in the study area. Conclusively, the overall hydrochemical and stable isotope evaluations revealed a recharge predominantly derived from meteoric (rainfall) source while the corresponding low TDS is a reflection of low water–rock interaction and limited migratory history of the shallow groundwater system in the study area.
Keywords: Shallow groundwater; Basement terrain; Hydrochemical facies; Stable isotope; Meteoric water

The present work aims at assessing the water quality index (WQI) in the surface water of Sankey tank and Mallathahalli lake situated in Bangalore Urban district by monitoring three sampling locations within Sankey tank (viz., A, B and C) and Mallathahalli lake (viz., Inlet, Centre and outlet) for a period of 3 months from March to May 2012. The surface water samples were subjected to comprehensive physico-chemical analysis involving major cations (Ca2+, Mg2+, Na+, K+, Fe2+), anions (HCO3, Cl, SO42−, NO3, F, PO43−) besides general parameters (pH, EC, TDS, alkalinity, total hardness, DO, BOD, COD, CO2, SiO2, colour, turbidity). For calculating the WQI, 14 parameters namely, pH, electrical conductivity, total dissolved solids, total hardness, alkalinity, calcium, magnesium, sodium, potassium, chloride, sulphate, nitrate, fluorides and iron were considered. SAR values indicated that both Sankey tank and Mallathahalli lake waters are excellent (S1) for irrigation, while electrical conductivity values classified these lake water, respectively under medium salinity (C2) and high (C3) salinity category. Correlation between SAR and electrical conductivity revealed that Sankey tank water is C2S1 (medium salinity-low sodium) type while Mallathahalli lake water is C3S1 (high salinity-low sodium) type. Sankey tank and Mallathahalli lake water were, respectively hard and very hard in nature. Further, it is apparent from WQI values that Sankey tank water belongs to good water class with WQI values ranging from 50.34 to 63.38. The Mallathahalli lake water with WQI value ranging from 111.69 to 137.09, fall under poor water category.
Keywords: Sankey tank; Mallathahalli lake; Water quality index; SAR; Percent sodium

Heterogeneous Fenton process using steel industry wastes for methyl orange degradation by Mohamed E. M. Ali; Tarek A. Gad-Allah; Mohamed I. Badawy (263-270).
Steel industry wastes (iron-containing waste) could be used as a Fenton-catalyst for the decolorization of methyl orange dye. Various reaction conditions were investigated including catalyst concentration, hydrogen peroxide concentration and pH value. The obtained results indicated that the dye degradation rate increases with increasing catalyst and hydrogen peroxide (H2O2) concentrations and with decreasing pH value. Over 98 % decolorization of the dye was achieved within 30 min at optimum reaction conditions; 200 mg/L catalyst and 34 mM H2O2 concentrations at pH 2 for 20 mg/L initial dye concentration. Reaction kinetics was also carried out to determine the order of reaction in both catalyst and H2O2 concentrations. Stability and reusability of Iron-containing waste were investigated. The iron-containing waste as catalyst can be reused several times with nearly same efficiency of Fenton-like oxidation of MO.
Keywords: Steel waste; Fenton-like reaction; Methyl orange; Decolorization

Hydrogeochemical assessments were carried out in the vicinity of Okpara coal and Obwetti fireclay mines, Enugu, Nigeria to investigate the hydrogeochemical characteristics and constituents of shallow groundwater. A total of 12 representative shallow groundwater samples were collected and analyzed for major cations and anions as well as trace metals like Fe and Mn. Distribution of major ions in these groundwater samples was calculated and the general trend among cations and anions was found to be Ca → Na → Mg → K and SO4 → NO3 → Cl → HCO3, respectively. This means that water moving through the ground will react to varying degrees with the surrounding minerals (and other components), and it is these rock–water interactions that give the water its characteristic chemistry. Piper trilinear diagrams classified the hydrogeochemical facies into Ca–Mg–Cl, Ca–Fe–Mg–SO4 and Ca–Mg–Na–K–Cl–SO4 water types. Ratios of Cl to Na, K and Mg generally increased compared to those of Cl to Ca and SO4 which decreased indicating ion adsorption/exchange processes due to the dissolution of drainage materials. The aquiferous units mainly in the northwestern region of the study area yield water of better quality than those toward the southeastern region.
Keywords: Hydrogeochemistry; Water samples; Water types; Groundwater quality

Polymethacrylic acid grafted psyllium (Psy-g-PMA): a novel material for waste water treatment by Ranvijay Kumar; Kaushlendra Sharma; K. P. Tiwary; Gautam Sen (285-291).
Polymethacrylic acid grafted psyllium (Psy-g-PMA) was synthesized by microwave assisted method, which involves a microwave irradiation in synergism with silver sulfate as a free radical initiator to initiate grafting reaction. Psy-g-PMA grades have been synthesized and characterized on structural basis (elemental analysis, FTIR spectroscopy, intrinsic viscosity study) as well as morphological and thermal studies, taking psyllium as reference. The effects of reaction time, amount of monomer and silver sulfate (free radical initiator) on grafting of PMA on psyllium backbone have been studied. It is observed that all the grades of Psy-g-PMA have higher intrinsic viscosities than that of psyllium. The best synthesized grade was Psy-g-PMA having intrinsic viscosity of 6.93 and 58 % grafting of PMA on the main polymer backbone. Further Psy-g-PMA applications as flocculants for waste water treatment have been investigated. Psy-g-PMA resulted in higher decrease in the flocculation parameters such as total dissolved solid or total solids compared to psyllium. Hence the result shows the possible application of grafted psyllium in wastewater treatment.
Keywords: Psyllium; Polymethacrylic Acid; Silver sulfate; Flocculation

Removal of arsenic(III) and arsenic(V) on chemically modified low-cost adsorbent: batch and column operations by Palas Roy; Naba Kumar Mondal; Shreya Bhattacharya; Biswajit Das; Kousik Das (293-309).
Batch and column operations were performed utilizing thioglycolated sugarcane carbon (TSCC), a low-cost adsorbent, to remove As(III) and As(V) from aqueous systems. Under optimized batch conditions, the TSCC could remove up to 92.7 and 91.4 % for As(III) and As(V), respectively. An artificial neural network model showed the validity of TSCC as a preferable adsorbent for arsenic [As(III) and As(V)] removal in batch studies. In column operations, removal efficiency increases with increase in influent arsenic concentration and adsorbent dose and decreases with increase in flow rate. At an adsorbent dose of 6.0 g, flow rate 3.0 mL min−1, and initial arsenic concentration 1,500 μg L−1, the arsenic uptake capacity of TSCC for As(III) and As(V) was found to be 85.01 and 83.82 μg g−1, respectively. The Thomas model was used to analyze the column experimental data. Results from the column operations indicated that the adsorption behavior of arsenic [As(III) and As(V)] fits exceptionally well with the Thomas model with high correlation coefficient and very low standard error. Examinations of scanning electron microscopy and FTIR spectroscopy reveal that high arsenic adsorption favors surface complexation on the adsorbent surface.
Keywords: Arsenic; Removal; Low-cost adsorbent; Batch; Column

Evaluation of some heavy metal loading in the Kpeshi lagoon, Ghana by Joseph R. Fianko; Cynthia Laar; Juilet Osei; Alfred K. Anim; Abass Gibrilla; Dickson Adomako (311-319).
A study was carried out on the Kpeshi lagoon to evaluate the relative contributions of some heavy metals (Na, k, Ca, K, Fe, Mn, Ni, Cr, Cd, Al, Pb) on the current state of the Kpeshi lagoon. The lagoon water was sampled along with some fish samples. Water pH, electrical conductivity and total dissolved salts were measured in situ whilst Na and K were measured using flame emission spectrometry. Heavy metals (iron, manganese, nickel, aluminium, chromium, lead and cadmium) in both water and fish samples were analyzed using atomic absorption spectrometry. Measured pH values ranged between 6.60 and 7.87, a mean conductivity and total dissolved salts of 87.31 ± 19.14 μS/cm and 38.4 ± 8.43 mg/L, respectively. Nutrient and organic matter were among the frequent source of pollution in the lagoon with mean sulphate, phosphate and nitrate concentrations of 190 ± 108.84, 1.62 ± 0.49 and 0.89 ± 0.26 mg/L, respectively. Iron and aluminium in the lagoon water measured the highest concentration of 13.2 ± 3.47 and 13.6 ± 4.29 mg/L, respectively. Fish samples however revealed very high concentrations of calcium and potassium measuring 15,709 ± 75.35 and 5,949.49 ± 87.30 mg/kg, respectively. Sodium and aluminium also revealed relatively high concentrations: 3,775.70 ± 24.80 and 708.47 ± 4.95 mg/kg, respectively. Notably, sites closer to settlement community (Teshie Township, e.g. S1, S2, S3 and S4) and the hospitality industries (i.e. dotted hotels, e.g. S7) appeared to be relatively more contaminated.
Keywords: Assessment; Bioaccumulation; Fish; Kpeshi lagoon; Metals; Pollution; Water

The adsorption of Cu(II), Cd(II) and Ni(II) ions from aqueous solutions by activated sludge and dried sludge was investigated under laboratory conditions to assess its potential in removing metal ions. The adsorption behavior of metal ions onto activated sludge and dried sludge was analyzed with Weber–Morris intra-particle diffusion model, Lagergren first-order model and pseudo second-order model. The rate constant of intra-particle diffusion on activated sludge and dried sludge increased in the sequence of Cu(II) > Ni(II) > Cd(II). According to the regression coefficients, it was observed that the kinetic adsorption data can fit better by the pseudo second-order model compared to the first-order Lagergren model with R 2  > 0.997. The adsorption capacities of metal ions onto activated sludge and dried sludge followed the sequence Ni(II) ≈ Cu(II) > Cd(II) and Cu(II) > Ni(II) > Cd(II).
Keywords: Activated sludge; Dried sludge; Heavy metals; Adsorption; Copper(II); Cadmium(II); Nickel(II)

Environmental contamination due to anthropogenic and natural sources is increasing day by day because of increase in population, industrialization and urbanization. Arsenic species released into the environment tend to persist indefinitely, circulating and eventually accumulating throughout the food chain, thus becoming a serious threat to the environment. The present study explores the effectiveness of Leucaena leucocephala seed powder (agricultural waste) in removing arsenic ions from aqueous solution. Batch studies were carried out to characterize As (III) and As (V) removal capability of L. leucocephala seed powder. Maximum biosorption capacity for As (III) and As (V) was found to be 81.88 and 92.61 %, respectively. Amino acid–arsenic interaction has been highlighted on the basis of shifting of FTIR bands of native LLSP. Morphological changes and reduction in pore area have been observed in modified LLSP. Modification on the native LLSP results into the increase in percentage sorption of As (III) and As (V) up to 85 and 99 %, respectively. Enhancement in the percentage sorption is due the increase in the stability of the biosorbent due to increase in the final decomposition temperature of the modified LLSP. The findings showed that L. leucocephala seed powder can easily be envisaged as a new, vibrant, low-cost biosorbent for arsenic clean-up operations.
Keywords: ModificationLeucaena leucocephala seed powder; Arsenic; Decontamination; Bioremediation

Birnessite nanorod-mediated decomposition of methylene blue with common oxidants by R. Kannan; K. Govindan; S. Selvaraj; P. Ravichandiran; S. Vasanthkumar (335-341).
In this paper, the birnessite nanorods (BN) were synthesized by microwave-assisted hydrothermal method and was characterized by powder X-ray diffraction measurements (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), and surface area (BET) analyzer. These results confirm the formation of birnessite nanorods. The catalytic decomposition profile of methylene blue by birnessite nanorods was tested. The effect of oxidants peroxomonosulfate (PMS) and peroxodisulfate (PDS) was compared with hydrogen peroxide (H2O2). Among these oxidants, PDS exhibits a high degree of decomposition of more than 80 % mineralization, achieved in 4 h when compared to PMS and H2O2. The decomposition was examined using varying amount of catalyst, which showed the dye decomposition activity to be proportional to the amount of the catalyst. The powder XRD studies showed no changes in the structure of birnessite nanorods, implying that these reactions are surface controlled.
Keywords: Birnessite; Manganese oxide; Methylene blue; Hydrogen peroxide; Peroxomonosulfate; Peroxodisulfate

Simultaneous enzymatic hydrolysis and anaerobic biodegradation of lipid-rich wastewater from poultry industry by Gisanara Dors; Adriano A. Mendes; Ernandes B. Pereira; Heizir F. de Castro; Agenor Furigo Jr. (343-349).
Simultaneous enzymatic hydrolysis and anaerobic biodegradation of lipid-rich wastewater from poultry industry with porcine pancreatic lipase at different concentrations (from 1.0 to 3.0 g L−1) were performed. The efficiency of the enzymatic pretreatment was measured by the Chemical Oxygen Demand (COD) removal and formation of methane. All samples pretreated with lipase showed a positive effect on the COD removal and formation of methane. After 30 days of anaerobic biodegradation the methane production varied from 569 ± 95 to 1,101 ± 10 mL for crude wastewater and pretreated at 3.0 g L−1 enzyme, respectively. COD removal of wastewater supplemented at different enzyme concentrations was found to be threefold higher than crude wastewater. The use of lipases seems to be a promising alternative for treating lipid-rich wastewaters such as those from the poultry industry.
Keywords: Lipase; Enzymatic hydrolysis; Anaerobic biodegradation; Poultry wastewater