NOPR Collection:

Cashew-nut husk Natural Dye Extraction Using Taguchi Optimization: Green Chemistry Approach

Tue, 01 Sep 2015 00:00:00 GMT

Title: Cashew-nut husk Natural Dye Extraction Using Taguchi Optimization: Green Chemistry Approach Authors: Patil, P D; Rao, C R; Wasif, A I; Anekar, S V; Nagla, J R Abstract: Using natural dyes instead of their synthetic counter parts is very good example of implementation of green chemistry principles. The present study is focused on optimization of extraction conditions during natural dye extraction from cashew-nut husk, an agro-waste. Taguchi technique was employed for optimizing the parameters namely particle size of the raw dyestuff, solid-liquid ratio, time of extraction and method of extraction assistance. The results indicated 150 micron particle size; 1:20 as solid-solvent ratio, three hours for extraction and enzyme addition as assistance for extraction as the optimum conditions for extraction. The absorbance values for the control and optimum extraction runs were found to be 0.945 and 1.381 respectively. The extraction carried out with optimum conditions showed significant improvement in the extraction efficiency in terms of 46 % increase in the dye yield. Page(s): 512-517

Parametric Investigation and optimization of Near-Dry Electrical Discharge Machining

Tue, 01 Sep 2015 00:00:00 GMT

Title: Parametric Investigation and optimization of Near-Dry Electrical Discharge Machining Authors: Pandey, H; Dhakar, K; Dvivedi, A; Kumar, P Abstract: This study investigates near-dry Electric Discharge Machining (EDM) in order to achieve higher Material Removal Rate (MRR), lower Tool Wear Rate (TWR) and Better surface finish than conventional EDM on High Speed Steel (HSS) workpiece. Taguchi L₂₇ orthogonal array was used for conducting experimentation. The experiments have been conducted by mixing of limited quantities of water with high pressure air (air-mist). This paper presents a relatively simple device to be used for applying the near-dry EDM. The near-dry EDM does not produce toxic fumes so called Environment friendly machining process for the applied operating conditions, the near-dry electrical discharge machining presents some advantages regarding the machined surface quality and the electrode tool wear, in comparison with the machining that uses liquid dielectric. The effect of different process parameters like applied current, duty factor, gap control, sensitivity, tool lift was analyzed on MRR, surface finish and tool wear rate. Page(s): 508-511

Mixing Torque Measurement - an Effective Tool for Identifying Critical Binder Volume Concentrations for Ceramic Processing

Tue, 01 Sep 2015 00:00:00 GMT

Title: Mixing Torque Measurement - an Effective Tool for Identifying Critical Binder Volume Concentrations for Ceramic Processing Authors: Sanikommu, N; Bhargavi, K; Suresh, M B; Johnson, R; Joshi, A S Abstract: Ceramic processing of powders, mixed with additives, can be classified into three regimes: CBVC [Critical Binder Volume Concentration], sub CBVC and post CBVC which correspond to viscous plastic processing, compaction processing and colloidal processing respectively. These regimes can be estimated experimentally by measuring the mixing torque for different ratios of the powder to additive concentration. In the present study, the torque required for mixing is indirectly estimated by measuring the torque of the AC motor that drives the blender. Analysis of the Torque v/s Volume Concentration curve permits delineation of the three zones. Our present study was carried out using alumina powder mixed with a binder. The developed torque was logged in a paperless chart recorder, with built-in storage memory. Page(s): 504-507

Anaerobic treatment of high sulphate containing pharmaceutical wastewater

Tue, 01 Sep 2015 00:00:00 GMT

Title: Anaerobic treatment of high sulphate containing pharmaceutical wastewater Authors: Chelliapan, S; Sallis, P J Abstract: The effect of different organic loading rate (OLR) to an anaerobic reactor performance and sulphate reduction was investigated. Sulphate concentration in the feed varied from 100 to 3000 mg.L^-1 and up to 97% removal efficiency was observed at OLR 0.43 - 1.23 kg COD.m^-3.d^-1. However, the removal efficiency showed some decline (to 53 – 67% removal) at OLR 1.53 – 3.73 kg COD.m^-3.d^-1, probably due to high sulphate concentration in the feed during this period. At a reactor OLR of 1.86 kg COD.m^-3.d^-1(HRT 4 d), the soluble COD reduction was around 70 - 75%. Nevertheless, when the OLR was increased to 2.48 - 3.73 kg COD.m^-3.d^-1, the COD removal efficiency decreased to 45%. The microbial aspects of sulphate reducing bacteria (SRB) results indicated that sulfidogenic bacteria, such as Desulfovibrio, had contributed substantially to the treatment process (around 16 – 36% when the reactor was operated at OLR 0.86 – 2.98 kg COD.m^-3.d^-1). Page(s): 526-530