Department Of Environmental Science And Technology

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/84

Browse

Subject: search.filters.subject.Fly ash

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Studies on the Use of Fly Ash and Crop Residue Biochar in Soil Amelioration and Nutrient Uptake in Wheat
    (Central University of Punjab, 2018) NAG, SHILPA; Garg, V.K. and Babu, J. Nagendra
    Catalytic pyrolysis of rice straw using fly ash as catalyst was studied in various gravimetric proportions of 1:3, 1:1 and 3:1 (fly ash : rice straw, w/w). The thermogravimetric analysis (TGA ) of the thermal degradation of rice straw in presence of fly ash and its subsequent kinetic analysis by Coats-Redfern equation showed a decrease in the activation energy. The pyrolysis was conducted in a laboratory scale batch reactor maintained at 400, 500 and 600 oC pyrolysis temperatures under slow pyrolysis conditions (10 oC/min). The pyrolysis furnishes three components namely biochar/biochar-fly ash composites (35-90%), bio-oil (4-22%) and syn-gas (6-48%) characteristic of slow pyrolysis conditions. The syn-gas obtained from catalytic pyrolysis were analysed and characterized using GC-TCD analysis to reveal CO2, CH4 and H2 as the major constituents with no traces of CO observed is accounted to fly ash metal oxide catalysed CO to CO2 conversion. The bio-oil obtained from catalytic pyrolysis upon GC-MS analysis, showed an increase in depolymerization of lignin and fragmentation and dehydration of the carbohydrate residues as the major processes operative in presence of fly ash. The results were further affirmed by the Ultimate (CHNO) analysis, 1H-NMR and HSQC 2D-NMR analysis for the catalytic pyrolysis biooil. The biochar and biochar-fly ash composites were characterized for their Ultimate analysis, Functional groups (FTIR and Boehm Titration), SEM-EDS, physico-chemical properties (pH, EC, alkalinity, total phosphate), surface area, micronutrients and its leaching characteristics and Cu(II) adsorption. The O/C and H/C atomic ratios for biochar and biochar fly ash composites decreased with increase in the pyrolysis Name of student Shilpa Nag Registration Number CUP/MPh-PhD/SEES/EVS/2010-11/07 Degree for which submitted Doctor of Philosophy Supervisor Prof. (Dr.) V. K. Garg Co-Supervisor Name Dr. J. Nagendra Babu Department Centre for Environmental Science and Technology School of Studies School of Environment and Earth Sciences Key words Crop residue, Biochar, Fly ash, Soil, Wheat iv temperature. Functional group analysis further reiterated the results with oxygenated functional groups like lactone and carboxylic acids present at lower temperature biochar whereas only phenols were present in case of high temperature biochar. Biochar were alkaline and with increase in the fly ash content the pH of the composites tend to be less basic. Cu(II) adsorption was characteristically observed to increase with increase in the fly ash content in the biochar obtained from catalytic pyrolysis at 500 oC. The biochar and biochar-fly ash composites were ameliorated to soil and changes in the physicochemical properties namely pH, EC, CEC, water holding capacity, total Phosphorus and available Phosphorus, of soil were characterized. The biochar-fly ash composite also prepared externally using biochar obtained at various pyrolysis temperatures with fly ash, mixed in proportion as calculated for the catalytic pyrolysis biochar obtained. The soil ameliorated with biochar-fly ash composite prepared from catalytic pyrolysis were compared with the soil ameliorated with externally mixed biochar-fly ash composite for various soil physicochemical properties. The plant growth of Triticum aestivum was studied for the full crop cycle. The plant growth parameters namely – root length, shoot length, photosynthetic pigments, cellular respiration, antioxidant enzymes, crop height were studied. The results of the study were compared statistically using one way and two way ANOVA. The ANOVA analysis revealed that all the plant growth parameters tend to show a significant change with the biochar/biochar-fly ash composites obtained at various pyrolysis temperatures and their composition. Regression analysis revealed the significant change with all the chemical and biological properties measured at different stages of Triticum aestivum and biochar/biochar-fly ash composite ameliorated soil physicochemical properties. The parameters indicate oxidative stress in case of the plants grown on the biochar and biochar-fly ash ameliorated soils.
  • Thumbnail Image
    Item
    Removal of hexavalent chromium from aqueous solution using biomass derived fly ash from Waste-to- Energy power plant
    (Taylor & Francis, 2013) Vaid, Upma; Mittal, Sunil; Babu, J. Nagendra
    Fly ash from the agricultural waste-based Energy Power Plant has been studied for the adsorption of hexavalent chromium [Cr(VI)]. In order to maximize the Cr(VI) removal from simulated aqueous solutions, effects of various parameters i.e. adsorbent dose (10–40 g/L), contact time (5–90 min), variation in pH (1–5), and initial metal ion concentration (10–80 mg/L) on Cr(VI) adsorption were investigated by batch adsorption experiments. It was observed that adsorption of Cr(VI) on the selected adsorbent was dependent on pH. Before optimization of experimental conditions, the percent removal of Cr(VI) from the aqueous solution (10 mg Cr/L) was approximately 4%, which increased to approximately 99% after optimization of experimental conditions. Maximum adsorption was observed upon adding 10 g/L of adsorbent to a 60 mg Cr/L aqueous solution at pH 1.0 and contact time of 90 min at 200 rpm. Equilibrium adsorption data were well fitted in Langmuir isotherm model which substantiate monolayer adsorption of Cr(VI) on fly ash. Kinetics of Cr(VI) adsorption on fly ash follows pseudo-second-order reaction.
  • Thumbnail Image
    Item
    Characterization, activity and process optimization with a biomass-based thermal power plant's fly ash as a potential catalyst for biodiesel production
    (Royal Society of Chemistry, 2015) Kumar, P.; Aslam, M.; Singh, N.; Mittal, S.; Bansal, A.; Jha, M.K.; Sarma, A.K.
    A typical thermal power plant operated using a solid biomass mixture as fuel, which comprised 70-80% gram straw, 10-15% cotton straw, 5-10% wheat straw and leaves (2%) with a small quantity of coal (1-2%) initially used for smooth ignition, produces a residue called Biomass-Based Thermal Power Plant Fly Ash (BBTPFS). BBTPFS was investigated for composition and structural characterization using different techniques. The versatile composition of the BBTPFS was confirmed by XRF analysis that indicated the weight percent of different components viz. CaO (30.74%), SiO2 (27.87%), K2O (13.96%), MgO (6.67%), SO3 (4.83%), Cl (3.36%), Al2O3 (2.83%), Fe2O3 (2.36%), P2O5 (1.34%), Na2O (1.14%), small quantities of TiO2, SrO, MnO, BaO, ZrO2, ZnO, Rb2O, Br, Cr2O3, CuO, NiO and As2O3 as active ingredients. The SEM and TEM image analysis showed the surface morphology of the BBTPFS which was found to be mixed in nature, having 1 to 500 nm range particles with meso, micro and macro porosity. BBTPFS was used as a catalyst for transesterification of Jatropha curcas oil having a high percentage of free fatty acids and appropriate process optimization was achieved using the Taguchi-ANOVA method. It was observed that at a temperature of 225?C and an internal vapour pressure of 3.2 MPa in a batch reactor with 5% catalyst loading, 1:9 mol mol-1 of oil-alcohol and 3 h reaction time, the optimum yield of biodiesel obtained was ?93.9%, which is in agreement with the theoretical value. The product quality was assessed and found to conform to ASTM and EN-standards. ? The Royal Society of Chemistry 2015.