Nutrients assessment of anaerobic palm oil mill effeluent (AnPOME) as an alternative media for microalgae culture

The main aim of the present study is to investigate the availability of macronutrient andmicronutrient in AnPOME. All collected samples were analyzed using HACH method. Theresults reveal that the C/N and N/P ratio of the AnPOME is six times more than the theoreticalvalue. Concentration of micronutrients also shown higher concentration range compared tothat of the Bold Basal Medium (BBM). However, the concentration of phosphorus inAnPOME six times lower than nitrogen indicates that phosphorus limitation in AnPOME.Hence, this finding suggested the best microalgae to be grown in AnPOME is mixotrophic orheterotrophic mode. Overall, reuse of AnPOME replacing synthetic growth is highlyrecommended considering that enough composition of macronutrient and micronutrient inAnPOME and inexpensive alternative to synthetic media.Keywords: microalgae; Anaerobic Palm Oil Mill Effluent (AnPOME); BBM; macronutrient;micronutrient

Pressure stresses generated due to supersonic steam jet induced hydrodynamic instabilities

The phenomenon that involves direct contact of steam with water is called Direct Contact Condensation (DCC). This phenomenon has been observed/prevailed in most of the power and process industries. The phenomenon of direct contact condensation involves heat, mass and momentum transfer across the highly fluctuating interface between steam jet and surrounding water giving this process an intricate nature to be studied. More recently the observation of hydrodynamic instabilities at the interface between supersonic steam jet and water has given a new facet to the study of DCC. In the current study the equivalent von-Mises Stress, equivalent elastic strain and total deformation in the Perspex vessel that has been incurred due to the pressure stresses has been studied. These pressure stresses have been generated due to the condensing supersonic steam jet induced hydrodynamic instabilities. It has been investigated first by experimentally observing the temperature fluctuations in axial and radial directions across supersonic steam jet which actually depicts these instabilities. Then Direct Contact Condensation (DCC) model has been used to conduct the CFD study using a commercial code Ansys®. Accompanied with this a mock up study has been done in which the pressure loads computed using DCC model have been coupled to the Perspex vessel structure using one way Fluid Structure Interaction (FSI) analysis in Ansys® to compute the true scale equivalent von-Mises Stress, equivalent elastic strain and total deformation generated by hydrodynamic instabilities induced pressure stresses. On true scale, hundreds of Pico scale deformation has been computed in the Perspex vessel confinement

Solvent fermentation from palm oil mill effluent using clostridium acetobutylicum in oscillatory flow bioreactor

Acetone-butanol-ethanol (ABE) fermentation from Palm Oil Mill Effluent (POME) by C. acetobutylicum NCIMB 13357 in an oscillatory flow bioreactor was investigated. Experimental works were conducted in a U-shaped stainless steel oscillatory flow bioreactor at oscillation frequency between 0.45-0.78 Hz and a constant amplitude of 12.5 mm. Fermentations were carried out for 72 hr at 35oC using palm oil mill effluent and reinforced clostridia medium as a growth medium in batch culture. Result of this investigation showed that POME is a viable media for ABE fermentation and oscillatory flow bioreactor has an excellent potential as an alternative fermentation device

Optimization of nickel oxide nanoparticle synthesis through the sol-gel method using Box-Behnken design

In this study, nickel oxide nanoparticles were prepared using the sol-gel method. The process parameters were optimized to produce smaller size of nanoparticles such as molar ratio, solution pH and calcination temperatures. The Box-Behnken method was selected as the statistical prediction method with the aim of reducing the number of experimental runs which will directly save time and chemicals and thereby reducing the overall cost. The size of the nickel oxide particles was selected as the response of the synthesis process and was determined using X-ray diffraction. The optimum predicted conditions were obtained at a molar ratio of 1:1.74, solution pH of 1.02 and calcination temperature of 400.08 degrees C. The particle size from the optimized experimental conditions was found to be 14.31nm which was in good agreement with the predicted value of 13.74nm. These results were justified by the relatively high correlation coefficients (R2=0.9859 and R2adj=0.9677) of the statistical prediction.NPRP grant # [5-1425-2-607] from the Qatar National Research Fund (a member of Qatar Foundation)Scopu

CFD based Hydrodynamic Parametric study of inclined injected Supersonic steam into subcooled water

Hydrodynamic parametric study of the supersonic steam injection into subcooled water is investigated.The phenomenon of direct-contact condensation, used in steam driven jet injectors, nuclear reactor emergency core cooling systems and direct-contact heat exchangers was investigated computationally by injecting an inclined steam jet without the presence of non condensable gases using a supersonic nozzle submerged in subcooled water. Ansys Fluent based Euler-Euler multiphase model is used. The angle of inclination is varied from 450 to 00 with a decrement of 200 for each computation with the constant inlet pressure of 7 bars and water temperature of 300C. It was found that the temperature and pressure near the nozzle exit showing an abrupt height with the instantaneous condensation upon venting. The hydrodynamic Gaussian profile width is more in the case of vertical injection as compare to the inclined injection which depict the effect of static water fluid pressure and gravity on pressure head and temperature