Sensitivity analysis of steam power plant-binary cycle

This paper analyses a steam power – two-stage binary cycle plant (SPP–2BCP), in which low temperature waste heat from a conventional steam power plant can be efficiently utilized to generate electricity by installing a bottoming binary cycle. The result from a previous calculation on the installation of binary cycle technology on a Steam Power Plant (SPP) with n-Pentane working fluid indicates an increase in plant efficiency of about 9%. The purpose of this study is to analyze the sensitivity of performance of the binary cycle system against variations in the SPP operational load and the condenser’s cooling water temperature. The calculation is conducted on SPP load variations of 25%, 50%, 75% and 100%, inlet turbine pressure variations of 5 bar–30 bar, and inlet turbine temperature variations of 125 °C up to 235 °C. Each of these is also analyzed with ambient cooling water temperatures of 30 °C–37 °C. The results of the analysis indicate that the performance of this binary cycle SPP degrades slightly with SPP load, turbine inlet temperature, and turbine inlet pressure variations and with cooling water variations.     

A parametric study on structural effects of hollow hybrid fin heat sinks in natural convection and radiation

Journal of Mechanical Science and Technology - This study investigates structural effects of hollow hybrid fin heat sinks (HHFHSs) under natural convection and radiation conducting parametric...     

Multivalent binding interaction of alcohol dehydrogenase on dye-metal affinity matrix

The optimization of a chromatographic process using immobilized metal affinity chromatography requires an understanding of the factors that govern the interaction between proteins and immobilized metal ions. Factors, such as concentrations of protein, NaCl and imidazole were investigated to elucidate kinetics of adsorption of alcohol dehydrogenase (ADH) onto a dye-iminodiacetic acid matrix (dye-IDA matrix). The results indicate that the adsorption of ADH onto a dye-IDA matrix occurs in the mode of multiple-site binding interactions between ADH and zinc ions immobilized on the dye-IDA matrix. The estimated average number of interaction sites was 4.5 and the association constant was 6 x 10(-9) mM(-n). The isotherm of ADH adsorption was well represented by a multivalent model of protein-zinc ion interactions. For the adsorption of ADH from clarified yeast homogenate, addition of imidazole as a protein competitor to adsorption buffer increased the adsorption specificity of ADH, thereby suppressing contaminant protein adsorption. It was also observed that the adsorption of ADH was better performed at high initial protein concentrations in the yeast homogenate. Consequently, these results may have important implications on the optimization of the strategy for immobilized metal affinity adsorption in packed and expanded bed systems.     

Application of Response Surface Methodology for the Optimization of β-Carotene-Loaded Nanostructured Lipid Carrier from Mixtures of Palm Stearin and Palm Olein

The main purpose of this study was to optimize a β-carotene-loaded nanostructured lipid carrier (βC-NLC) using the lipid matrix of palm stearin and palm olein and Tween 80 as a surfactant. The NLC was prepared by using the high shear homogenization method. Box–Behnken Design (BBD) response surface methodology (RSM) was applied to optimize the process and formulation. A three-factor experimental model was used to optimize the combination of palm stearin ratio (A, %w/w), lipid:surfactant ratio (B, %w/w), and (lipid+surfactant):water ratio (C, %w/w). The formulations were evaluated for their responses on particle size (Y1), polydispersity index (Y2), zeta potential (Y3), and encapsulation efficiency (Y4). Subsequently, Fourier-transform infrared spectroscopy (FTIR), thermal (DT-TGA), x-ray diffraction (XRD), transmission electron microscopy (TEM), and in vitro release (Franz diffusion cell) analyses were utilized to observe the resulting optimum formulation. The optimum formulation was obtained at a combination of A (5.5:4.5), B (1:4.9), and C (24:76) %w/w. This resulted in βC-NLC having a particle size of 166 nm, polydispersity index of 0.35, zeta potential of −26.9 mV, and an encapsulation efficiency of 91.2%. No strong interaction between different NLC components was observed based on FTIR, DT-TGA, and XRD profiles. Round-shaped NLC particles were observed under TEM. Franz diffusion cell observation resulted in diffusion profile of β-carotene of 110.6 μg cm⁻² with a flux of 1.06 (μg cm⁻² hour⁻¹). This indicates that palm stearin and palm olein can be prospectively developed as βC-NLC.     

Enzymatic glycerolysis–interesterification of palm stearin–olein blend for synthesis structured lipid containing high mono- and diacylglycerol

Food Science and Biotechnology - The objective of this research was to evaluate enzymatic glycerolysis–interesterification to synthesize structured lipids (SLs) containing high...     

Valorisation of Jatropha curcas L. plant parts: Nut shell conversion to fast pyrolysis oil

The biorefinery concept is a very powerful concept to optimise the conversion of biomass resources to value-added products with a minimum loss of energy and mass and a maximum overall value of the production chain. We here report our activities on the application of this concept to valorise the Jatropha curcas L. (JCL) shrub, a (sub)-tropical plant producing a high quality plant oil that may be converted to biodiesel in good yields. Within a research consortium of Dutch and Indonesian researchers, we are exploring high added value outlets for byproducts of the JCL plant (leaves, latex) and seed processing units (press cake). As an example, we here report fast pyrolysis experiments to convert the nut shells to fast pyrolysis oil, a promising second generation biofuel. The fast pyrolysis experiments were carried out in a continuous bench scale pyrolyser at a throughput of 2.27 kg/h at 480 °C and atmospheric pressure. The nut shell pyrolysis oil was obtained in 50 wt.% yield, the remainder being char (23 wt.%), gas (17 wt.%) and ash. Relevant product properties of the oil were determined and indicate that the oil is inhomogeneous in nature.