http://localhost:8081/jspui/handle/123456789/110 2025-07-01T16:27:13Z http://localhost:8081/jspui/handle/123456789/17460 Title: MODELING OF DIMETHYL ETHER SYNTHESIS FROM METHANOL IN FIXED BED REACTOR Authors: Puri, Sakshama Abstract: The extraordinary property of DME made it an alternative to LPG, natural gas and diesel. DME has attracted attention of many researchers from industrial purposes. Methanol dehydration carried out in adiabatic fixed bed reactor is production process of DME synthesis. In present work, the reactor is preceded by feed preheater has been simulated under unsteady state conditions. Non linear Partial differential equation was solved considering it to one dimension pseudo homogenous model. Validation of model was done on comparing simulation results with experimental data. For model simulation, adiabatic fixed bed reactor was packed with 1.5 mm y-A1203 pellets as catalyst. The process occurred in the temperature range of 543-603 K at atmospheric pressure. Also, the effect of WHSV, temperature, and flow rate on conversion of methanol was monitored. By adding water to methanol feed, catalyst deactivation take place rapidly. Hence, the results were obtained considering pure methanol as a feed. 2013-06-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17383 Title: REMOVAL OF ARSENIC FROM SIMULATED WASTE WATER USING PHYTOREMEDIATION: AN ADVANCED NATURAL METHOD Authors: Singh, Anurag Kumar Abstract: Arsenic is toxic due to which many types of diseases spread in the living being. In last - decades, many countries reported various types of arsenic related diseases around the world. Removal of arsenic from the water is a great concern due to its highly toxic and carcinogenic nature. Due to rapid industrialization the contamination of arsenic in water has been increased. This causes serious ill effect to the human being. Various techniques are available to remove arsenic from wastewater. Among the available techniques the phytoremediation is most popular technique for the removal of arsenic from water as well as from soil. Phytoremediation is the new emergent technology in which plants are used to remove the heavy metal from contaminated wastewater. In the present research work, the removal efficiency of arsenic from contaminated wastewater by submerged plant water hyacinth (Eichhornia Crassipes) has been studied. Arsenic concentration was measured using ICPMS. Characterization of plant water hyacinth was carried out by using FTIR, by measuring weight and height of the plant. The stress of arsenic on plant was determined by the analysis of decrement or increment of plant biomass. Bio-concentration factor value gives the hyperaccumulation of arsenic at initial concentration. The water hyacinth had capacity to eliminate or consume toxic element arsenic from the wastewater. Effect of initial arsenic concentration - of arsenic removal was investigated in our present work. Maximum removal efficiency was obtained as 53.63% at initial concentration of 1 mg/L at the end of 81h day of experiment period. It was observed that removal decreases with the increase in initial concentration of Arsenic. It was also observed that Water hyacinth remediated arsenic maximum at the concentration of 1 mg/L. This shows that the uptake rate of the plant was low when the concentration was high. Moreover, it was also found that the removal efficiency of the plant was sensitive to the pH changes. 2015-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17381 Title: STUDYAND SIMULATION OF FLUID-PARTICLE FLOW IN PIPE BEND Authors: Anirudh Abstract: A dilute, particle-laden flow in a pipe with a 900 bend is modelled using a RANS approach, coupled to a second-moment turbulence closure, together with a Lagrangian particle tracking technique, with particle dispersion modelled using a stochastic approach that ensures turbulence anisotropy. Detailed predictions of particle mass concentaion profile at angle cut of 00, 15° and 45° f'or particles of I j.un. 50im. I 00tiii diameter paticles and particle velocities are validated through comparisons of predictions with experimental measurements made for gas—solid flows in a vertical-to-horizontal flow configuration. Reasonable agreement between predicted first and second moments and data is found for both phases, with the consistent application of anisotropic and three-dimensional modeling approaches resulting in predictions that compare favorably with those of other authors, and which provide fluctuating particle velocities in acceptable agreement with data. 2015-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17380 Title: MODELLING AND SIMULATION OF METHANE BI-REFORMING FOR SYNGAS PRODUCTION - IN A MICRO-STRUCTURED REACTOR Authors: Sahu, Bhavana Abstract: Methane reforming processes such as steam reforming, dry reforming, partial oxidation, and auto thermal reforming, produce syngas mixture of different H2/CO ratio. Bi-reforming of methane is considered in this study which is a combination of steam reforming and dry/carbondioxide reforming. It provides the flexibility to manipulate inlet CO2/CI-14 and F120/CH4 ratio for syngas production of desired 1-12/CO ratio. Nowadays, methanol is considered as future fuel (e.g. dirnethyl ether) and is raw material for numerous chemical products. A mixture of methanol and dirnethyl ether has high cetane number and is an exceptional diesel engine fuel. However, methanol production requires syngas composition of 2:1 and it can be easily produced from bi-reforming of methane. In the present study, a pseudo-homogenous one-dimensional single channel reactor model for bi-reforming over Ni-Ce02/MgAl204 catalyst has been developed and simulated using MATLAB R20I3b software. Kinetic parameters of bi-reforming reactions over Ni- - CeO2/MgAl2O4 catalyst are obtained from literature. Reactor model equations are solved using stiff ODE solver ODE 15S. The process variables (temperature, pressure and feed composition) - are optimized and the reactor performance is evaluated under obtained optimum condition. Four decision variables namely, temperature, pressure, H20/Cl-1 ratio and CO2/Cl-14 ratio are considered for optimization. Maximization of objective functions. i.e. C114 and CO2 conversion has been done to obtain optimum condition using genetic algorithm (GA). It is found that hi-reforming reactions are favored at high temperature. low pressure. The optimum temperature, pressure, CH4/l-120/CO2 ratio are found to be 1173 K. I bar and 1/0.8/0.4 respectively. Under optimum condition 99% Cl-L1 and 82% CO2 conversions are reached resulting in l-12/CO ratio of 2. Yield of H2 and CO is found to be 2.65 and 1.32 respectively. This process is an excellent approach to obtain syngas of desirable 112/CO ratio (-2) suitable for methanol and Fischer-Tropsch synthesis. 2015-05-01T00:00:00Z