Applied Water Science (v.4, #3)

Environmental perspectives of Phragmites australis (Cav.) Trin. Ex. Steudel by Jatin Srivastava; Swinder J. S. Kalra; Ram Naraian (193-202).
Extensive research is being conducted worldwide to find alternative and efficient systems to lessen the impacts of climate change and reduce environmental pollution. The genus Phragmites has proven ability to mitigate the environmental pollution of its surroundings. Common reed (Phragmitesaustralis (Cav.) Trin. Ex. Steudel), a graminaceous plant of cosmopolitan nature, has been extensively studied especially for the mitigation of environmental contamination. The capability of common reed to grow well at extreme environmental conditions such as elevated CO2 and high temperature is conferred by several factors such as change of carbon trapping mechanism (from C3 to C4 and vice versa), microbial association and biochemical adaptations. P. australis has been a most preferred unique plant system, especially in ecological engineering for improving the quality of wastewater. This paper reviews the current state of knowledge regarding the suitability of Phragmites australis for environmental remediation and summarizes recent advancements in our understanding of this grass.
Keywords: Phragmites australis ; Environmental contamination; C3C4Ecological engineering

Evaluation of water resources around Barapukuria coal mine industrial area, Dinajpur, Bangladesh by M. Farhad Howladar; Pulok Kanti Deb; A. T. M. Shahidul Huqe Muzemder; Mushfique Ahmed (203-222).
Water is a very important natural resource which can be utilized in renewable or non-renewable forms but before utilizing, the evaluation of the quality of this resource is crucial for a particular use. However, the problems of water quality are more severe in areas where the mining and mineral processes’ industries are present. In mining processes, several classes of wastes are produced which may turn into ultimately the sources of water quality and environmental degradation. In consequences, the evaluations of water quality for livestock, drinking, irrigation purposes and environmental implications have been carried out around the Barapukuria Coal Mining Industry under different methods and techniques such as primarily the field investigation; secondly the laboratory chemical analysis and thirdly justified the suitability of the laboratory analysis with statistical representation and correlation matrix, Schoeller plot, Piper’s Trilinear diagram, Expanded Durov diagram, Wilcox diagram, US salinity diagram, Doneen’s chart and others. The results of all surface and ground water samples analysis show that the characteristics and concentrations of all the major physical and chemical parameters such as pH, EC, TDS, Na+, K+, Ca2+, Mg2+, Fetotal, Cl, HCO3, CO32− and SO42− are varied from one sample to other but well analogous with the WHO and EQS standard limit for all purposes in the area where the abundance of the major ions is as follows: Ca2+ > Na+ > Mg2+ > K+ > Fetotal = HCO3 > SO42− > Cl > CO32−. The graphical exposition of analytical data demonstrates two major hydrochemical facies for example: calcium-bicarbonate (Ca2+- HCO3) and magnesium-bicarbonate (Mg2+- HCO3) type facies which directly support the shallow recently recharged alkaline water around the industry. The calculated values for the evaluation classification of water based on TDS, Na%, EC, SAR, PI, RSC, MH, and TH replicate good to excellent use of water for livestock, drinking and irrigation activities except in some cases. For example, the high hardness in both water samples specifies the active hydraulic relation between surface and groundwater. Moreover, the statistical application and interpretation exhibit a good positive correlation among most of the water constituents which might be the indicator of having tightly grouped, precise homogeneous good-quality water resources around the mining industry. Finally from the environmental degradation point of view, it can be implied that there are no significant parameters or factors observed which are much badly effective on environment except very few cases. Thus, this research strongly recommends for monitoring the water quality in every 6 months or annually around this industry which might be positive for keeping the safe environment and healthy production of the coal mine.
Keywords: Barapukuria coal mine; Quality of water; Livestock; Drinking and irrigation; Statistical correlation matrix; Environmental implication

Reclamation of highly calcareous saline-sodic soil using low quality water and phosphogypsum by M. A. Gharaibeh; M. J. Rusan; N. I. Eltaif; O. F. Shunnar (223-230).
The efficiency of two amendments in reclaiming saline sodic soil using moderately saline (EC) and moderate sodium adsorption ratio (SAR) canal water was investigated. Phosphogypsum (PG) and reagent grade calcium chloride were applied to packed sandy loam soil columns and leached with canal water (SAR = 4, and EC = 2.16 dS m−1). Phosphogypsum was mixed with top soil prior to leaching at application rates of 5, 10, 15, 20, 25, 35, 40 Mg ha−1, whereas calcium chloride was dissolved directly in water at equivalent rates of 4.25, 8.5, 12.75, 17.0, 21.25, 29.75, and 34 Mg ha−1, respectively. Both amendments efficiently reduced soil salinity and sodicity. Calcium chloride removed 90 % of the total Na and soluble salts whereas PG removed 79 and 60 %, respectively. Exchangeable sodium percentage was reduced by 90 % in both amendments. Results indicated that during cation exchange reactions most of the sodium was removed when effluent SAR was at maximum. Phosphogypsum has lower total costs than calcium chloride and as an efficient amendment an application of 30 Mg ha−1 and leaching with 4 pore volume (PV) of canal water could be recommended to reclaim the studied soil.
Keywords: Phosphogypsum; Reclamation; Saline; Sodic; Leaching; Canal water

The removal efficiencies for chemical oxygen demand (COD), ammoniacal nitrogen (NH3–N), and color, as well as ozone consumption (OC) from the Malaysian semi-aerobic landfill stabilized leachate using ozone reactor, were investigated. Central composite design with response surface methodology was applied to evaluate the interaction and relationship between operating variables (i.e., ozone dosage, COD concentration, and reaction time) and to develop the optimum operating condition. Based on statistical analysis, Quadratic models for the four responses (COD, NH3–N, color, and OC) proved to be significant with very low probability values (<0.0001). The obtained optimum conditions were 70 g/m3 ozone, 250 mg/l COD, and 60 min reaction time. The results obtained by the predicted model were 26.7, 7.1, and 92 % removal for COD, NH3–N, and color, respectively, with 9.42 (kgO3/kg COD) OC. The predicted results fitted well with the results of the laboratory experiment.
Keywords: Stabilized leachate; Ozonation; Optimization process; Response surface methodology (RSM)

Geochemical evaluation of fluoride contamination of groundwater in the Thoothukudi District of Tamilnadu, India by C. Singaraja; S. Chidambaram; P. Anandhan; M. V. Prasanna; C. Thivya; R. Thilagavathi; J. Sarathidasan (241-250).
Fluoride is a chemical element that has been shown to cause significant effects on human health through drinking water. Different forms of fluoride exposure are of importance and have shown to affect the body’s fluoride content and thus increasing the risks of fluoride-prone diseases. Fluoride has beneficial effects on teeth; however, low concentrations of fluoride intensify the risk of tooth decay. Fluoride can also be quite detrimental at higher concentrations at skeletal fluorosis. The Thoothukudi District is a hard rock and alluvial plain marked as one of the Fluoride-increase area in Tamilnadu due to occurrence of various rock types including fluoride-bearing minerals. The F content of groundwater can thus originate from the dissolution of Fluoride-bearing minerals in the bed rock. Hundred representative groundwater samples from Thoothukudi District were collected during two different seasons. Samples were analysed for F, other major cations and anions. The study area is chiefly composed of hornblende biotite gneiss, charnockite, alluvio marine, fluvial marine and granite with small patches of quartzite and sandstone. Higher concentration of fluoride is observed during pre-monsoon (3.3 mg l–1) compared to the post-monsoon (2.4 mg l–1) due to the dilution effect. Spatial distribution and factor score show that higher concentrations of F are noted in the north and central part of the study area owing to lithology. Bicarbonate is well correlated with F which explains that both ions were derived from the weathering. While F has a very weak correlation with pH which may be due to the increase of alkalinity resulting from the increase of carbonate and bicarbonate ions.
Keywords: Fluoride; Drinking water; Hard rock; Lithology; Weathering

To enhance our understanding of the dynamic characteristics of groundwater level in the western Jilin Province of China, two models of decomposition method in time series analysis, additive model and multiplicative model, are employed in this study. The data used in the models are the monthly groundwater levels of three wells observed from 1986 to 2011. Moreover, the analysis of three wells, located in the upper, middle and downstream of the groundwater flow path, helps to obtain the variation in each well and the mutual comparison among them. The final results indicate that the groundwater levels show a decreasing trend and the period of variation last for about 7 years. In addition, hydrographs of the three wells manifest the impacts of human behavior on groundwater level increases since 1995. Furthermore, compared with the autoregressive integrated moving average model, the decomposition method is recommended in the analysis and prediction of groundwater levels.
Keywords: Groundwater level; Time series analysis; ARIMA model; Forecasting; Western Jilin Province

Quebracho colorado tannin extract was used as a coagulant raw material for water and wastewater treatment. The chemical synthesis follows a Mannich reaction mechanism and provides a fully working coagulant that can remove several pollutants from water. This paper addresses the optimization of such synthesis and confirms the feasibility of the coagulant by testing it in a preliminary screening for the elimination of dyes and detergents. The optimum combination of reagents was 6.81 g of diethanolamine (DEA) and 2.78 g of formaldehyde (F) per g of tannin extract. So obtained coagulant was succesfully tested on the removal of 9 dyes and 8 detergents.
Keywords: Water coagulation; Quebracho colorado; Tannins; Natural treatment; Design of experiments

A novel activated carbon was prepared from Rhazya stricta leaves and was successfully used as an adsorbent for phenol removal from aqueous solution. The prepared activated carbon was characterized by FTIR and SEM analysis. Three factors (namely, temperature, pH and adsorbent dose) were screened to study their effect on the adsorption of phenol by R. stricta activated carbon. A 23 full factorial design was employed for optimizing the adsorption process. The removal of phenol by adsorption onto R. stricta carbon reached 85 % at a solution pH of 3, an adsorbent dose of 0.5 g/l and a temperature of 45 °C. The temperature and adsorbent weight had a positive effect on phenol removal percentage, when both factors were changed from low to high and the opposite is true for the initial solution pH. The results of the main effects showed that the three studied factors significantly affected phenol removal by R. stricta carbon with 95 % confidence level. The interaction effects revealed that the interaction between the temperature and pH had the most significant effect on the removal percentage of phenol by R. stricta activated carbon. The present work showed that the carbon prepared from a low-cost and natural material which is R. stricta leaves is a good adsorbent for the removal of phenol from aqueous solution.
Keywords: Adsorption; Activated carbon; Phenol; Factorial design; Rhazya stricta

The ever-increasing number and production capacity of petroleum refineries in recent years have intensified the need for developing an effective and practical method for treating their wastewaters. In this study, the application of Fenton process with scrap iron powder was investigated for the treatment of a bio-refractory petroleum refinery effluent. Response surface methodology was employed with a cubic IV optimal design to optimize the process using chemical oxygen demand (COD) removal as the target response. H2O2/COD, and H2O2/Fe mass ratios as well as pH were considered as the relevant parameters. A COD removal of more than 83 % was achieved under optimal conditions (H2O2/COD 10.03, H2O2/Fe 2.66 and pH 3.0) within 90 min. Kinetics studies were conducted to investigate the effect of reaction time on COD removal. In addition, the role of post-coagulation on COD removal under optimal conditions was investigated and it was found that 37 % of COD removal occurred due to coagulation, indicating its high potential in the Fenton process.
Keywords: Petroleum refinery wastewater; Fenton-based treatment; Scrap iron; Response surface methodology (RSM); Post-coagulation

Application of chlorofluorocarbons (CFCs) to estimate the groundwater age at a headwater wetland in Ichikawa City, Chiba Prefecture, Japan by Zhiwei Han; Changyuan Tang; Jingqiu Piao; Xing Li; Yingjie Cao; Touma Matsumaru; Chipeng Zhang (291-302).
To delineate the groundwater flow system in a basin, the groundwater age was estimated by analyzing chlorofluorocarbons (CFC-11, CFC-12 and CFC-113) in a typical headwater wetland in Ichikawa, Japan. Feasibility of groundwater dating by CFCs was assessed comprehensively based on the concentrations of NO3, SO42−, Fe2+ and dissolved CH4 in the groundwater, because the CFCs would be degraded under the reduction condition available in a wetland. It was found that the CFC-11 apparent age was much older than that estimated by other CFC species. It showed that CFC-12 and CFC-113 were suitable tracers for groundwater dating because of their stability in the wetland environment. Furthermore, the mixture of groundwater with different age was discussed by CFC-12 and CFC-113 based on the binary mixing model and piston-flow model. As a result, the apparent age of groundwater in the study area is in the range of 38–48 years.
Keywords: Reduction condition; CFCs; Groundwater age; Mixing model; Groundwater flow

Potential of KMnO4 and H2O2 in treating semi-aerobic landfill leachate by Nabihah Abdullah; Hamidi Abdul Aziz; N. N. A. N. Yusuf; Muhammad Umar; Salem S. Abu Amr (303-309).
Treatment of recalcitrant landfill leachate was carried out using hydrogen peroxide (H2O2) and potassium permanganate (KMnO4). The treatment performance was reported in terms of colour, chemical oxygen demand (COD) and ammoniacal nitrogen (NH4-N). The effect of oxidant dosages and pH was determined and optimum conditions were determined considering the removal of parameters of interest. The optimum dosage of both oxidants was similar in terms of COD removal; however, H2O2 gave better removal (42 %) and similar results were obtained for NH4-N (24 %). KMnO4 proved better in terms of colour with a reduction of 74 % compared to 43 % by hydrogen peroxide at pH 7. Acidic conditions (pH 2–5) proved conducive towards the removal of all parameters with the exception of COD removal by KMnO4 that exhibited a low removal at pH 5 and increased with increasing pH. The COD reduction at pH 3 was ~38 % for KMnO4 and H2O2, whereas the reduction in NH4-N was 22 and 28 % for KMnO4 and H2O2, respectively. The COD and NH4-N removal performance of H2O2 was better compared with KMnO4; however, consistently higher colour removal was obtained for KMnO4.
Keywords: Landfill leachate; Hydrogen peroxide; Potassium permanganate; COD; Ammoniacal nitrogen