Publications by authors named "Babu J Alappat"

Composite indicators (CIs) are being utilized more frequently to assess and monitor environmental systems. The revised leachate pollution index (r-LPI) is one such composite indicator used to quantify the pollution potential of landfill leachate on a scale of 5-100. The development of CIs involves several steps, and each of these steps has various methodological choices, each of which could lead to different results.

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A critical evaluation of strategies used for reducing start-up time and biological wastewater treatment using an inverse fluidized bed reactor (IFBR) was done. The start-up of an IFBR is one of the most important, time-consuming, and limiting steps in wastewater treatment using biofilm reactors. Evaluation of different strategies used by various researchers is helpful in future research works with this reactor.

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A tool to quantify the pollution potential of leachate, termed the revised leachate pollution index (r-LPI), has been developed. It was developed using the fuzzy Delphi analytic hierarchy process (FDAHP). The formulation entails four major steps: parameter selection, weight calculation, normalization of parameters, and aggregation of the parameters.

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The comparative performance of an inverse fluidized bed reactor (IFBR) having high density polyethylene beads as carrier materials for biofilm formation and a continuous stirred tank reactor (CSTR), both maintaining autotrophic denitrification using biogenic sulphur (ADBIOS) in the absence and presence of nickel (Ni), was studied. The reactors were compared in terms of NO-N and NO-N removal and SO-S production throughout the study. A simulated wastewater with an inlet NO-N concentration of 225 mg/L and a decreasing concentration of biogenic sulphur (bio-S) from 1.

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  This study tested the feasibility of adsorptive removal of ZnO nanoparticles using activated carbon from wastewater. The effects of pH (5, 6, 7, 8, and 9) and nanoparticle/activated carbon concentration ratios (10, 1, 0.1, 0.

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The aim of this study was to understand the effects of pH (5, 6, 7, 8, 9) and activated carbon (AC) concentration (0.01, 0.1, 1, 10, 100 g/L) on the removal of a colloidal solution of nanoparticles (NPs) (ZnO + CuO) using AC in batch kinetic studies.

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The estimates of airborne fine particle (PM) concentrations are possible through rigorous empirical correlations based on the monitored PM data. However, such correlations change depending on the nature of sources in diverse ambient environments and, therefore, have to be environment specific. Studies presenting such correlations are limited but needed, especially for those areas, where PM is not routinely monitored.

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Generally speaking, landfilling is one of the prominent methods of waste disposal around the globe, but some under-developed and developing countries still continue to practice uncontrolled open dumping of waste. These uncontrolled landfills pose a relatively high threat to the various elements of the environment in comparison with the conventional engineered landfills that are used in many developed countries. However, some closed, un-engineered landfills do exist in developing countries.

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An index known as leachate pollution index (LPI) for quantifying the leachate contamination potential of municipal landfills had been developed and reported by the authors. It is a quantitative tool by which the leachate pollution data of landfill sites can be reported uniformly. LPI is an increasing scale index and has been formulated based on the Delphi technique.

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