Optimization of the processes is one of the most important tasks today, for highly competitive industries. High cost of research and development activities has necessitated development of the experimental methods by which the factors affecting a process could be determined by performing a minimum number of experiments. These types of experimental designs have been used since 1980.Among different methods of experimental designs, the Taguchi method -because of its comprehensive nature and its ability to enable designs which are resistant to uncontrollable parameters has found wide spread applications.The Sarcheshmeh copper ore, which mainly consists of Chalcopyrite, was studied by Taguchi method. The effect of seven factors namely collectors, Z11 and R407, frothers, pine oil and A65, particle size, pH and residence time were investigated. The results showed that an increase of minimum of 5% in copper recovery could be obtained using the Taguchi type of experimental design.

Backgrounds and Objectives: in recent years, mobile bed biological reactors have been used progressively for municipal and industrial wastewaters treatment. Dissented experiment is a trial that significant changes will accrue for influent variables in the process, and generally used for identification of the effective factors and optimization of the process. The scope of this study was determination of the optimized conditions for the MBBR process by using of Taguchi method.Materials and Methods: Reactor start up was done by using of the recycled activated sludge from Ahwaz wastewater treatment plant. After that and passing the acclimation period, with hydraulic residence time equal to 9 hours matched for 1000, 2000 and 3000 mg/l based on COD respectively, for optimization determination of the acclimated microbial growth, the variables change (pH, nitrogen source, chemical oxygen demand and salinity) were determined in 9 steps, and all of the results were analyzed by Qualitek -4 (w32b).Results: In this study, organic load removal based on COD was 97% and best optimized condition for MBBR were (inf. COD=1000 mg/l, pH=8, salinity=5% and the Nitrogen source=NH4CL).Conclusion: Based on our finding, we may conclude that Taguchi method is on of the appropriate procedure in determination the optimized condition for increasing removal efficiency of MBBR.

Manganese steels have extensively application in industries due to good resistance to wear, high work hardening capability with high toughness and ductility. Heat treatment is the main process to obtain desired mechanical properties and microstructure in this steel. The austenitizing temperature, the austenitizing time and the rate of quenching by increasing salt content are the main factors in heat treatment. For dissolving of carbide, the austenitizing temperature and austenitizing time are very important. Quenching rate must be high for minimizing the grain boundary carbids. In this research the effects of these input parameters on the grain boundary carbide content, austenite grain size and hardness have been critically analyzed using Taguchi method. In the optimization by Taguchi approach, L9 (3)3 array, employing nine experiments, with three levels for each factor, was chosen for DOE. It has been found that the austenitizing temperature is the most important process parameter affecting the carbide content, grain size and hardness. The heat treatment produces the minimum carbide content and low grain size when the process parameters were set at their optimum values. It has been shown that heat treatment parameters set as their optimum levels can ensure significant improvement in the objectives.

This paper presents a methodology, based on the taguchi parameter design approach, for the optimization of process parameters for bismuth recovery from aqueous solutions. The process parameters considered are [Bi3+], [NaCl], temperature, and cathodic current density. In addition, cell voltage and current efficiency as two responses have been considered. An orthogonal array L9, the signal-to-noise (S/N) ratio, and the analysis of variance were used to analyze the effect of selected process parameters and their levels. From a metallurgical point of view, the separation and recovery of bismuth from a bismuth glance concentrate through leaching, purification and electrowining of chloride solutions were carried out. The optimum conditions for the selected parameter values were found as [Bi3+] (75 g/L), [NaCl] (25 g/L), temperature (65oC) and current density (100 A/m2). Finally, a mathematical model has been proposed and the results of a confirmatory run are reported to verify the results, which indicate that this methodology is more efficient in optimizing the process parameters.

Antibiotic production is a key area in biotechnology. To enhance the productivity and improve the economics, much attention has been paid on the improvement of the factors employed in the antibiotic production. Neomycin is an important aminoglycoside antibiotic used widely in pharmaceutical preparations. In this project, Neomycin production by Streptomyces fradiae was studied. Effective factors include: the composition of culture (starch media due to high polysaccharide carbon resource was selected), optimized pH of 7, temperature of 30°C shaking conditions was selected 150 rpm for 72 hr in electrical shaker or 400 rpm with 0.5 VVM air flux for 144 hr in 5 lit fermentor, the optimized production was 3760 mg/lit. Statistic Taguchi method was employed to optimize the production conditions. Results show that the media composition (soybean meal; MgSO4.7H2O; and starch) and pH were the most effective factors in production of Neomycin antibiotic.

Background and Objectives: Optimization of mazut biocracking with different variables is one of the bioengineering applications in petroleum industry. The purpose of this study was to optimize biocracking of mazut by native microorganisms.Materials and Methods: To optimize mazut cracking, using Taguchi method we run 32 experiments using seven factors including amount of microbial inoculation, initial pH, surfactant, glucose, phosphor source, nitrogen source and sea salt; each of them with four levels and factor of microorganism type with two levels for design of experiment using that 32 experiments were designed by them.Results: Results showed that microbial mixture, 0.016 OD600 microbial inoculations, pH 8.3, Tween80 concentration of 2 g/L, glucose concentration of 4 g/L, phosphate concentration of 5 g/L, ammonium concentration of 9 g/L and sea salt concentration of 0.5 g/L were optimized conditions for biocracking of mazut process.Conclusion: Optimized level for each factor was not essentially inevitably the highest or the lowest level. Based on the analysis of variance, phosphor source with 15.8% and pH with 14.8% had the highest effect among other factors; however overally, error factor with 31.6% had the highest influence. Amount of microbial inoculation with 0.63% had the lowest effect on optimizing biocracking of mazut.

In this work, characteristics of various ball bearing parameters are studied under different loads androtational speeds. By using Dimensional Analysis (DA), dimensionless parameters are computed which providessolution for a group of parameters. This analysis can be accomplished by using the Buckingham π-theorem. DAleads to reduction of the number of independent parameters involved in a problem. These independent parametersget expressed as dimensionless groups. These dimensionless groups are always ratios of important physicalquantities involved in the problem of interest. In modeling and experimentation, its main function is to reduce theamount of independent variables, simplify the solution, and generalize the results. It becomes an effective method, especially if a complete mathematical model of the investigated process is not known. Moreover, in the presentwork the Buckingham π-theorem is applied to find the influencing parameter π 5 by using the Taguchi method.

For large scale production of diphtheria toxin, Coryneabactrium diphtheria must be cultured in a nutrient medium, and optimum conditions. In this condition coryneabactrium produces maximum amount of toxin, which is used for, diphtheria vaccine production. For obtaining maximum yield, needed to find the optimum conditions and use a suitable statistical design 4 to determine the effects of factors and errors. For this reason in different statistical experiment designs we used orthogonal taguchi method. For this expects the orthogonal array L'16 was used for the following five factors: Concentrations of 1. N. Z Amine (gr/lit), 2. Iron (mg/lit), 3 Calcium, (mg/lit), 4. phosphate solution (ml/lit), 5. Growth factors solution (ml/lit) that all of them had four levels. Optimum condition and optimum response determined after analysis of experiment results. Final results showed in the optimum condition, toxin production level increased from 120lf/ml (over 60%) and comparable to other vaccine manufacturing of developed countries.