Environment
H. Tamadon Ghareghie; M. Yazdi; D. Yousefi Kebria; H. Aminirad
Abstract
Soil contamination is considered a controversial issue in most countries. Nowadays, it is important to clearly understand how pollutants influence the soil from different sources. Today, hydrocarbons are one of the most important sources of soil contaminants, which is considered as a fundamental issue ...
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Soil contamination is considered a controversial issue in most countries. Nowadays, it is important to clearly understand how pollutants influence the soil from different sources. Today, hydrocarbons are one of the most important sources of soil contaminants, which is considered as a fundamental issue at the global level. The current study aims to analyze and model the effect of simultaneous parameters (time and concentration) of phenols and naphthalene with different percentages (10, 15, 20 and 25%) together with the amount of bentonite in fine-grained sandy soil. The designed experiments made use of response surface methodology (RSM) and Design-Expert software to carry out a computer-based simulation. According to the proposed model, the amount of bentonite is most affected by the permeability of the soil. The obtained results also showed that the permeability significantly decreases in the light of increasing the percentage of phenol and naphthalene coupled with the amount of bentonite and the age of contamination. On average, an 80% reduction of permeability was observed in contaminated soil, which was found in the soil contaminated with naphthalene. According to the results of the synergistic effects of time, the considerable impacts of both the percentage of hydrocarbon pollutants and the amount of bentonite on the reduction of permeability are quite evident.
M. E. Kazemian; S. A. Gandjalikhan Nassab; E. Jahanshahi Javarana
Abstract
In the present work, the statistical analyses are presented to study the economic indexes of Net Present Value (NPV) and Simple Payback Period (SPB) as response functions for the Combined Cooling, Heating and Power (CCHP) system. The CCHP performance is simulated with the aid of thermodynamic modeling, ...
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In the present work, the statistical analyses are presented to study the economic indexes of Net Present Value (NPV) and Simple Payback Period (SPB) as response functions for the Combined Cooling, Heating and Power (CCHP) system. The CCHP performance is simulated with the aid of thermodynamic modeling, and also economic equations are presented for economic simulation. An attempt is made to study the effect of some economic factors (interest ratio, fuel cost, lifetime, and electricity sell price) on the system’s responses. Based on the Design of Experiment analysis, regression models are presented to quantify the effects of these parameters on the Net Present Value and Simple Payback Periods. This novel approach is developed utilizing the response surface methodology (RSM) based on the central composite design (CCD) method. Sensitivity analysis of the economic parameters was also examined in this research. Optimal values of these parameters were obtained for the two economic indexes as response functions.
M. Helmi; A. Hemmati; K. Tahvildari
Abstract
The transesterification of Amygdalus scoparia oil to biodiesel was performed and examined through the electrolysis method in the presence of KOH/Al2O3 as a heterogeneous catalyst at room temperature. A KOH/Al2O3 as solid base catalyst was prepared through the impregnation of Al2O3 with KOH solution (concentration ...
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The transesterification of Amygdalus scoparia oil to biodiesel was performed and examined through the electrolysis method in the presence of KOH/Al2O3 as a heterogeneous catalyst at room temperature. A KOH/Al2O3 as solid base catalyst was prepared through the impregnation of Al2O3 with KOH solution (concentration of 25g in 100 mL deionized water). The catalyst was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS). The transesterification key variables such as reaction time, methanol to oil molar ratio, and catalyst weight were optimized by applying the central composite design (CCD) approach. The maximum yield of 94% was obtained at the methanol to oil ratio of 10:1, catalyst weight of 1.6 wt/v%, voltage of 10 V, a reaction time of 2.30 h, 10 wt% acetone at room temperature (25 ᵒC). The characterizations of Amygdalus scoparia oil and biodiesel were specified using a gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FTIR) analyses.
J. O. Ighalo; A. A. Adelodun; A. G. Adeniyi; C. A. Igwegbe
Abstract
Statistical modelling was employed to analyze the effect of sorbate-sorbent interphase on the adsorption of pesticides and herbicides from aqueous media. The dataset used for this study was sourced from relevant and reputable published papers in the past five years. Sixty-six lines of data were analyzed ...
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Statistical modelling was employed to analyze the effect of sorbate-sorbent interphase on the adsorption of pesticides and herbicides from aqueous media. The dataset used for this study was sourced from relevant and reputable published papers in the past five years. Sixty-six lines of data were analyzed using response surface methodology (RSM) and historical data design (HDD) on Design expert. Five parameters were considered in the study: adsorbate’s relative molecular mass (RMM), adsorbent specific surface area (SBET), adsorbent effective surface area eSBET (i.e., the portion of the SBET occupied by the sorbate molecules), the water solubility of adsorbate, and adsorbate preferential adsorption (i.e., the ratio of the amount of sorbate on the sorbent to the amount in solution). From the analysis of variance, it was observed that the SBET of the adsorbent was the most significant determining for the adsorption capacity, q (at a significance level of p <0.05). Other significant factors were the RMM, eSBET, and the preferential adsorption. Generally, solubility did not show any significant influence on the q. The response surface model had an R2 value of 0.9945 and an adjusted R2 value of 0.9927. Conclusively, the q of an adsorbent towards an herbicide or a pesticide increases with increasing eSBET and SBET, irrespective of the sorbate’s solubility and molecular mass.
G. Anju; B. Subha; M. Muthukumar; T. Sangeetha
Abstract
A treatment method based on the degradation of sago processing wastewater using ozonation process was conducted in this research study. The optimization of the process variables was designed with the aid of software called Design Expert and the technique was called response surface methodology (RSM) ...
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A treatment method based on the degradation of sago processing wastewater using ozonation process was conducted in this research study. The optimization of the process variables was designed with the aid of software called Design Expert and the technique was called response surface methodology (RSM) in Central composite design. The effect of ozonation variables like pH, treatment time and ozone concentration on the reduction of chemical oxygen demand (COD) of sago waste water was investigated. Interestingly, two different types of results like maximum removal of COD and optimum removal of COD were observed. Maximum COD removal of 62.45% was at pH 9.8, ozonation time 95.7 min, ozone dose 42% and optimum COD removal 0f 56.7% was at pH 9.8, ozonation time 35.7 min, and ozone dose 42%. Bacterial count was found to be nil after ozonation and microscopic observation of biomass proved that the sludge content had effectively reduced after ozonation treatment. It was determined that the ozonation of sago wastewater was a promising effort in wastewater treatment.
H. Joardar; M. K. Parida; A. K. Rout; I. Routaray
Abstract
In the present study the methyl ester of argemone oil, prepared by two step transesterification process due to its high acid value was experimented, in a variable compression ratio (VCR) multi-fuel engine to evaluate the combustion parameters like in cylinder pressure (Pr), net heat release rate (NHRR) ...
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In the present study the methyl ester of argemone oil, prepared by two step transesterification process due to its high acid value was experimented, in a variable compression ratio (VCR) multi-fuel engine to evaluate the combustion parameters like in cylinder pressure (Pr), net heat release rate (NHRR) and cumulative heat release rate (CHRR). For the current analysis engine load, compression ratio and bio-diesel blends are taken as input parameters. The mathematical models were developed and statistical significance was checked using analysis of variance (ANOVA). A second order model is developed and is found to be adequate by ANOVA results. The validation of the model is carried out by comparing the predicated values of output responses with that of experimental results.
C. Kurinjimalar; G. Kavitha; S. S. Begum; G. Rajaram; S. Nagaraj; N. Senthilkumar; R. Rengasamy
Abstract
Biofuel production by a sustainable method using microalgae is entirely dependent on biomass production. However, commercialization at large scale using microalgae is a major obstacle using analytical grade growth nutrients, due to their cost effectiveness. Hence, development of a cost effective method ...
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Biofuel production by a sustainable method using microalgae is entirely dependent on biomass production. However, commercialization at large scale using microalgae is a major obstacle using analytical grade growth nutrients, due to their cost effectiveness. Hence, development of a cost effective method is essential to reduce the production cost. Therefore, the present study envisaged the effect of low-cost commercial fertilizers such as urea, sodium bicarbonate, magnesium sulfate, potash and di-ammonium phosphate as growth nutrients for the production of biomass and total lipid of Botryococcus braunii were made. The biomass and total lipid production were optimized using Response Surface Methodology by 25 Central Composite Design. The result showed 225 mg L-1 of urea, 650 mg L-1 of sodium bicarbonate, 225 mg L-1 of magnesium sulfate, 150 mg L-1 of potash and 15 mg L-1 of di-ammonium phosphate supported the algal growth with a maximum biomass and total lipid of 0.792 gL-1 dry wt.. and 260 mg L-1 dry wt.., respectively. The biomass productivity of alga B. brauniiat the above condition recorded as 0.04 gL-1 day-1 with a generation time of 1.90 days.
