Publications (11) View all
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Article: Reuse Feasibility of Electrocoagulated Metal Hydroxide Sludgeof Textile Industry in the Manufacturing of Building Blocks
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ABSTRACT: During the last decade, the growing load of sludge fromtextile industries, the top foreign exchange earning sector of Bangladesh, is a common nuisance to environmental system and community health.The present study was aimed to minimize the environmental impact from the disposal of Electrocoagulated Metal Hydroxide Sludge (EMHS) by using it as a partial substitute of clay in the manufacturing of construction material like building blocks (BBs). Different batches of normal and pressurized building blocks (NBBs and PBBs, resp.) were prepared using up to 50% EMHS with clay and then fired at a particular temperature. EMHS proportion in the mixture and firing temperature were two key factors determining the quality of BB. BB did not show any deformation or uneven surfaces at any of the examined firing temperature. At higher firing temperature and EMHS proportion, more weight loss and shrinkage of BB were noticed. Higher compressive strength and lower water adsorption were found at lower EMHS content and higher firing temperature. It was explored that NBB and PBB with 20 and 30% EMHS in clay, respectively, and fired at 1050 ∘C would be usable for nonloading applications; namely, ornamental bricks, decoration purposes, and fence of garden.Journal of Wste Management. 01/2013; 2013:1-9. -
Article: Analysis of Heavy Metal in Electrocoagulated Metal Hydroxide Sludge (EMHS) from the Textile Industry by Energy Dispersive X-Ray Fluorescence (EDXRF)
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ABSTRACT: Environmental pollution due to discharges of heavy metal containing sludge from textile industries is a common nuisance in Bangladesh, where no treatment of sludge is carried out before final disposals. Energy Dispersive X-ray Fluorescence (EDXRF) was employed in the present study to analyze the heavy metal content of Electrocoagulated Metal Hydroxide Sludge (EMHS) collected from a composite textile industry. Thirteen heavy metals, viz., Mn, Ti, Cu, Zn, Ni, Sr, V, Cr, Zr, Hg, Cd, Nb and Ga, were detected. Mn, Ni, Cu, Zn and Cd exceeded the permissible limit to apply the EMHS in agricultural land. Cr, Ni, Cu and Zn were compared to the values of the European legislation to evaluate the environmental risk and to classify the wastes as inert wastes or as wastes that have to be control landfilled. EMHS was categorized as class I and needs to be deposited in controlled landfills.Metals. 12/2012; 2(4):478-487. -
Article: Assessment of Heavy Metal Contamination of Agricultural Soil around Dhaka Export Processing Zone (DEPZ), Bangladesh: Implication of Seasonal Variation and Indices
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ABSTRACT: Intense urbanization, large scale industrialization and unprecedented population growth in the last few decades have been responsible for lowering environmental quality. Soil contamination with metals is a serious concern due to their toxicity and ability to accumulate in the biota. The present work assessed the heavy metal contamination of agricultural soil in the close vicinity of the Dhaka Export Processing Zone (DEPZ) in both dry and wet seasons using different indices viz., index of geoaccumulation (I geo), contamination factor (C), degree of contamination (C), modified degree of contamination (mC d) and pollution load index (PLI). Samples were collected from the surface layer of soil and analyzed by Atomic Absorption Spectrophotometer (AAS). The trend of metals according to average concentration during the dry and wet seasons was As > Fe > Hg > Mn > Zn > Cu > Cr > Ni > Pb > Cd and As > Fe > Mn > Zn > Hg > Cu > Ni > Cr > Pb > Cd, respectively. Because of seasonal rainfall, dilution and other run-off during the wet season, metals from the upper layer of soil were flushed out to some extent and hence all the indices values were lower in this season compared to that of the dry season. I geo results revealed that the study area was strongly and moderately contaminated with As and Hg in the dry and wet seasons respectively. According to C , soil was classified as moderately contaminated with Zn, Cr, Pb and Ni, considerably contaminated with Cu and highly OPEN ACCESS Appl. Sci. 2012, 2 585 contaminated with As and Hg. The general trend of the mean C was Hg > As > Cu > Zn > Ni > Cr > Pb > Fe > Mn > Cd and As > Hg > Cu > Cd > Zn > Ni >Pb > Fe > Mn in dry and wet seasons, respectively. The mC f values in the dry and wet seasons were 575.13 and 244.44 respectively indicating an ultra high degree of contamination. The C d values in both seasons were associated with a very high degree of contamination. PLI results indicated immediate intervention to ameliorate pollution in both seasons. The main sources of metals included effluents from wastewater treatment plants, treated and untreated wastewater from surrounding industrial establishments as well as agricultural activities. Protecting the agricultural soil is a formidable challenge in the study area, which requires modernization of industries, thereby improving the recovery and recycling of wastewater. Indices analysis presented in the present work could serve as a landmark for contemporary research in toxicology.Applied Sciences. 07/2012; 2(3):584-601. -
Article: Characterization of Brick Making Soil: Geo-engineering, Elemental and Thermal Aspects
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ABSTRACT: Present study was carried out to investigate the basic geo-engineering, elemental and thermal properties of brick making soil using British Standard (BS) 1377, Energy Dispersive X-ray Fluorescence (EDXRF) and Thermogravimetric/Differential Thermal Analyzer (TG/DTA), respectively. Average moisture content, specific gravity, liquid limit, plastic limit, plasticity index, liquidity index and linear shrinkage of the soil were 43.4%, 2.7, 45.9%, 21.3%, 24.4%, 0.89 and 7.7%, respectively. In soil, iron and silicon were dominant earth materials with presence of Al, K, Ca, Ti, Mn, Zr, Ba, Cu, Ni and Zn. DTA and DTG showed distinct curves during heat treatment due to dehydration, transition from one crystalline form to another, destruction of crystalline structure, melting, oxidation, decomposition, degradation of soil. All experiments indicated that the soil was suitable for making good quality bricks.Jahangirnagar University Journal of Science. 06/2012; -
Conference Proceeding: Removal of BOD5 Municipal Wastewater by Electrocoagulation (EC) Technique: A Novel Approach
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ABSTRACT: In present study municipal wastewater was treated by electrocoagulation (EC) technique for reduction of BOD 5 up to standard level using sacrificial iron electrodes. Raw samples were collected from the drain just before of discharging into the Buriganga River covering area of Babubazar to Kamalbagh, Dhaka. The overall experiment was carried out at different current density, contact time (15, 30, 45 and 60 min), pH (pH 3, 5, 7 and 9), voltages (15, 30, and 45 volt) and electrode distances (2, 4, and 6 cm). The most effective operation condition for the effective removal (96.96%) of BOD 5 were15 min contact time, 15 volt, pH 7 and 4 cm electrode distance at 1.35 A current. This operation condition removed enough BOD 5 from the wastewater in lower time and voltage, without adding any chemical to fulfil the standard criteria for inland surface water set by Department of Environment (DoE), Bangladesh. The iron dissociation and sludge generation were 0.05 g/350ml and 0.3239 g/350ml, respectively. The cost of this operational condition was 13.37 Tk/m 3 , proving its cost effectiveness than the other treatment system. So EC can act as a novel system to treat heterogeneous municipal wastewater.An International Conference on Green Chemistry for Sustainable Development, Jessor Science & Technology University, Bangladesh; 05/2012
