Adaptive Adjustment of Injection Molding Process for Mechanical Characteristics Using the Taguchi Method and Response Surface Methodology

This study is analyzed variations of mechanical characteristics that depend on the injection molding techniques during the blending of short glass fiber (SGF) and polytetrafluoroethylene (PTFE) reinforced polycarbonate (PC) composites. Planning of experiment is based on a Taguchi orthogonal array table, and applied signal-to-noise ratios to determine an optimal setting. Simultaneously, applying response surface methodology (RSM) analysis, a mathematical predictive model of the tensile strength and flexural strength properties of mechanical characteristics were developed in terms of the injection molding process parameters. In addition, analysis of variance (ANOVA) also was applied to identify the effect of process parameters of SGF and PTFE reinforced PC composites for the tensile strength and flexural strength. Additional runs were conducted in order to validate the optimal setting and compare the performance of Taguchi method and RSM approach.     

Combination of Chemical Coagulation and Photo-Fenton Oxidation Process for the Treatment of Beet Sugar Industry Wastewater: Optimization of Process Conditions by Response Surface Methodology

The beet sugar industry generates large volumes of wastewater with high levels of chemical oxygen demand (COD) and color content, which are discharged into the nearby environment without adequate treatment. The aim of this study was to investigate the treatment possibility of this wastewater by using the photo-Fenton oxidation combined with a coagulation process. Central composite design and response surface methodology were used to evaluate the relationships between color and COD reduction and the photo-Fenton oxidation parameters (i.e. Fenton’s reagent dosage, pH, and reaction time).

The combined treatment results showed 59% of COD and 83.9% of color removal were obtained at optimum conditions (pH: 6.2; Fe²⁺ dosage: 20 ppm; H₂O₂ dosage: 1500 ppm; and reaction time of 15 min). Finally, the results of gel permeation chromatography showed that low molecular weight fraction of the wastewater impurities is more degraded than high molecular weight fraction during oxidation/coagulation process. Therefore, the results obtained from this study showed that an appropriate combined method for the treatment of beet sugar industry wastewater can be designed and implemented.