Modeling and Simulation
A. Ahmadpour; A. Haghighiasl; N. Fallah
Volume 15, Issue 1 , February 2018, , Pages 46-72
Abstract
In this research, photocatalytic degradation method has been introduced to clean up Spent Caustic of Olefin units of petrochemical industries (neutralized Spent Caustic by means of sulfuric acid) in the next step, adaptable method and effective parameters in the process performance have been investigated. ...
Read More
In this research, photocatalytic degradation method has been introduced to clean up Spent Caustic of Olefin units of petrochemical industries (neutralized Spent Caustic by means of sulfuric acid) in the next step, adaptable method and effective parameters in the process performance have been investigated. Chemical oxygen demand (COD) was measured by the commercial zinc oxide that synthesized with precipitation synthesis method in a two-shell photoreactor. The percent of reduction of COD in the photocatalytic process was modeled using Box–Behnken design and artificial neural network techniques. It was concluded that the ANN was a more accurate method than the design of experiment. The effect of important parameters including oxidant dosage, aeration rate, pH, and catalyst loading was investigated. The results showed that all of the parameters, except pH, had positive effects on increasing COD removal. According to the obtained results, adsorption and photolysis phenomena had a negligible effect on COD removal.
Transport Phenomena,
Leila Omidvar Langroudi; hassan pahlavanzadeh; sara nanvakenari
Volume 13, Issue 4 , November 2016, , Pages 96-112
Abstract
This study introduces an experimental and theoretical investigation of the performance of a proposed air dehumidification system using a nanofluid of γ-alumina nano-particles in LiBr/H2O as a desiccant. Comparative experiments organized using a central composite design were carried out to evaluate ...
Read More
This study introduces an experimental and theoretical investigation of the performance of a proposed air dehumidification system using a nanofluid of γ-alumina nano-particles in LiBr/H2O as a desiccant. Comparative experiments organized using a central composite design were carried out to evaluate the effects of six numerical factors (air velocity, desiccant flow rate, air humidity ratio, desiccant solution concentration, air temperature, desiccant temperature) and one categorical factor (adding nano-particles) on outlet air humidity ratio and outlet air temperature as responses. Reduced quadratic models were derived for each response. The results revealed that the concentration of LiBr/H2O solution and air temperature had the largest effect on outlet air humidity ratio and outlet air temperature, respectively. It was found that the average increase in mass transfer rate was 12.23% and heat transfer rate was 13.22% when γ-alumina nano-particles (0.02% wt) were added to the LiBr/H2O solution. The average increase in mass transfer coefficient was 22.73% and heat transfer coefficient was 26.51%.