Removal of copper from wastewater using thermally treated sewage sludge adsorbent without chemical activation

Abdel-Aziz M. H., Bassyouni M., Soliman M.F., Gutub S.A. and Magram S.F.

Removal of copper from synthetic wastewater by adsorption on sewage sludge adsorbent was studied. The sludge was dried, grinded and thermally treated at various temperatures. Surface morphology and chemical structure of treated sludge were investigated using SEM and FTIR. Parameters studied are initial concentration of copper ions, contact time, sludge dosage and the heat treatment temperature of the sludge. The removal efficiency of Cu+2 increases with increasing sludge dosage. Increasing initial concentration of Cu+2 has two opposing effects on the % removal depending on the concentration range used. Experimental data were modeled by using Langmuir and Freundlich isotherms. The data fits Freundlich linear model with R2 = 0.9585. The mechanism of adsorption of Cu+2 by sludge adsorbent was found to take place through a monolayer and heterogeneous surface. Possible applications of the present data in removing copper and other heavy metals from industrial effluents are highlighted.

Full Text

Policy of Eutrophication Control in Cirata Reservoir, West Java, Indonesia

Hasan Zahidah and Gunawan W.

The aim of this research is to understand the dynamics of ecosystem quality in Cirata reservoir that is utilized for fish net cage aquaculture (FNCA). The nutrient loading due to aquaculture and accelerated eutrophication was modeled by a system dynamics approach. The system dynamics model was divided into eutrophication and oxygen sub model. Both sub model simulations were run for 30 years and showed decreased oxygen at epilimnion and hypolimnion, meanwhile nutrient, biomass of phytoplankton, and detritus increased. Acceleration policy simulation mean fish farming accelerated showing that oxygen tended to rise and nutrient, biomass of phytoplankton and detritus tended to decline.

Full Text

Measurement of thermophysical properties of Al2O3/glycerin (G13) nanofluid for automotive radiator cooling applications

Kondru Gnana Sundari, Lazarus Godson Asirvatham, T. Michael N. Kumar and Nizar Ahammed

This paper deals with the measurement of thermo physical properties such as thermal conductivity, viscosity, surface tension and pH value of glycerin /Al2O3(G13) nanofluid. For the car radiator cooling applications, the base fluid G13 which contains glycerin is used as corrosion fighter and also acts as the anti-freezing agent. Low volume concentrations (0.05, 0.1 and 0.15%) of Al2O3 nanoparticles are dispersed in the base fluid (G13) and the effect of the nanoparticles are measured for the temperature ranging from 30°C to 50°C with an interval of 5°C each. The results showed an enhancement in thermal conductivity of 46.15% for 0.15% volume concentration of Al2O3 nanofluid for an average temperature of 40°C when compared with that of the base fluid. The decrement in viscosity of 33.84% has been observed as the temperature increases from 30°C to 50°C. The surface tension and pH value of the Al2O3/glycerin (G13) nanofluid are decreasing with the increase of temperature. The enhancement of thermal conductivity of this coolant with the addition of nanoparticles will yield promising results.

Full Text

Chromatographic characterization of some components of Balanites kernel oil

Abualreish M. J. A. and Al-Msiedeen A.M.

A sample of Balanites oil extracted from the fruit kernel of Hejlij tree grown in western Sudan was analyzed by some chromatographic methods. The saponifiable and the unsaponifiable contents of the oil were determined, it was found that the oil contains 84.56% fatty acids and 1.03 % sterols. The percentages of the fatty acids stearic, palmitic, oleic and linoleic in the oil were found as 7.18, 12.50, 30.90 and 34.34% respectively.

Full Text

Bacterial Diversity of Mineral Solubilizing Bacteria in Manganese Mining Area of Balaghat and Chhindwara, Madhya Pradesh, India

Dixit Shikha, Appu Kuttan K.K., Shrivastava Rahul and Singh Jaspreet

Balaghat and Chhindwara are the two main belts of manganese mining in Madhya Pradesh, India. The present research deals with the study of dumping zone of the same manganese mining area to get the iron oxidizing, sulfur oxidizing and phosphate solubilizing bacteria. The findings explore Phylum Proteobacteria, Firmicutes and Actinobacteria as major bacterial communities in the affected area. Mining area of Chhindwara was found more fertile and consists of diverse groups of bacteria. The major conclusion of study reveals that site can be easily reclaimed by providing proper irrigation and biofertilizers.

Full Text

Using the DNDC model to predict methane emissions from crop-rice rotation systems

Cha-un N., Chidthaisong A. and Towprayoon S.

Flooded rice cultivation is the major source of atmospheric methane (CH4) which makes an important contribution to global warming. In this study, we used a process-based model (DNDC) to simulate CH4 fluxes from 2.5-year consecutive cultivation of crop-rice rotation systems including fallow-rice (RF), rice-rice (RR), corn-rice (RC) and sweet sorghum-rice (RS). To test the accuracy of the model, simulation results and field observations were compared. The comparison found a higher correlation coefficient (r) in RF (0.9380), RC (0.9143) and RS (0.8883) than in RR (0.4805). A smaller relative error (E), root mean square error (RMSE) and percentage difference of total CH4 emissions were also observed in RF, RC and RS. These analysed results indicated that the DNDC model was in good agreement respecting quality and quantity estimation under fallow-rice and rotated crop-rice rotation systems. For the RR cropping system, the DNDC satisfactorily predicted total CH4 emissions but failed to capture the pattern of daily average CH4 fluxes. In long-term prediction, RC and RS are able to reduce annual CH4 emissions over 70% more than RR. These results suggest that the DNDC model can be used to predict CH4 emissions from crop-rice rotation systems in Thailand.

Full Text

Phytochemical characterization of the marine brown alga Turbinaria ornata

Gopalan Rajkumar and Periyakali Saravana Bhavan

In order to understand the phytochemical components of the edible seaweed, Turbinaria ornata, it was subjected to hexanic, acetonic and methanolic extactions. The alkaloids, terpenoids, flavonoids, polyphenols and quinones were present in the hexanic extract of T. ornata whereas alkaloids, terpenoids and flavonoids were absent in acetonic and methanolic extracts of T. ornata. Overall, presence of five secondary bioactive components {neophytadiene; 2-hexadecen-1-ol,3,7,11,15-tetramethyl-,[R-[R*,R*-(E)] ]; 17-pentatriacontene; 4,8,12,16-octadecatetraen -1-ol,4,9,13,17-tetramethyl; squalene} has been identified in T. ornata, of which four bioactive compounds except 4,8,12,16-octadecatetraen-1-ol,4,9,13,17-tetramethyl have been recorded in methanolic extract. Moreover, the presence of 17-pentatriacontene and squalene were unique only to methanolic extract of T. ornata. Further studies like isolation, purification and characterization of individual compounds are required to authentically tell their active principles.

Full Text

Effect of Gasification Parameters on Predicted Composition of Producer Gas of Unfermented Tea Waste by Equilibrium Modelling and Validation

Kumar Sonu and Pranav P.K.

Unfermented tea waste was obtained during drying and sorting operations in manufacturing of tea. The CHN analysis and higher heating value (HHV) results were used for modelling a down draft gasification process in terms of producer gas composition. A thermodynamic equilibrium modelling had been presented for a downdraft gasifier based on equilibrium constant with appropriate assumptions. The concept of equilibrium modelling applies well for prediction of the effect of gasification parameters (moisture content, equivalence ratio and reaction temperature) on gasification of unfermented tea waste. The predicted composition shows the effect of gasification parameters in relevant manner. The HHV of predicted gas is also affected by gasification parameters. The validation of modelling was done with experimental results at equivalence ratio (0.25), moisture content (12.6%) and reaction temperature (1023 K). It reveals that yield of hydrogen and carbon monoxide from experiment was almost two-third of model results but in case of carbon dioxide and methane, almost closer concentration was found. This model is quite satisfactory as hydrogen and carbon monoxide concentration is higher in model results than experimental results by one-third. This modelling is very helpful in predicting the yield of producer gas composition by varying the gasification parameters. The HHV from modelling is 32% higher than experimented results.

Full Text