4 research outputs found
Phenol red dye removal from wastewater using TiO2-FSM-16 and Ni-FSM-16 photocatalysts
Get PDFIn this study, the performance of Ni-FSM-16 and TiO2-FSM-16 photocatalysts in phenol red removal was explored. The XRD, FE-SEM, and BET tests were used to characterize the catalysts. All experiments were performed at ambient temperature and under UV (20 W). The parameters including dye concentration (20–80 mg/L), photocatalyst concentration (0–8 g/L), UV exposure duration, and contact time (0–160 min) were optimized using RSM software. BET values of Ni-FSM-16 and TiO2-FSM-16 were 718.63 m2/g and 844.93 m2/g, respectively. TiO2-FSM-16 showed better performance in dye removal than Ni-FSM-16. At pH 3, the maximum dye removal by TiO2-FSM-16/UV and Ni-FSM-16/UV was obtained 87% and 64%, respectively. The positive hole species had the main role in photocatalytic phenol red removal. The reusability study was done for up to 7 cycles, but the catalysts can be reused effectively for up to 3 cycles. The synergistic factor for the TiO2-FSM-16 and TiO2-FSM-16/UV processes were calculated to be 1.55 and 2.12, respectively. The dye removal efficiency by TiO2-carbon and Ni-carbon was slightly lower than those obtained by the FSM-16 ones. The TiO2-FSM-16 and Ni-FSM-16 catalysts had a suitable surface and acceptable efficiency in phenol red removal. © 2023 The Author
DEVELOPMENT OF DIFFERENTIAL QUADRATURE METHOD IN SINGLE-PHASE FLOW SIMULATION IN POROUS HYDROCARBON'S RESERVOIRS
No full textIn order to calculate the accurate prediction of fluid pressure in the reservoir and hydrocarbon's reservoir's simulation, numerical methods were developed. Different numerical methods, including finite difference method (FDM), finite element method (FEM), boundary element method (BEM), and finite volume method (FVM), were used to solve various engineering problems. However,
using these approximate numerical methods, the problem formulation becomes more complicated, and considerable computational effort is required to obtain acceptable solutions. To this end, researchers are always looking for more efficient and accurate numerical methods to increase the ability of numerical modeling. In this research, the development of the Differential Quadrature Method (DQM) in the fields of numerical simulation of hydrocarbon reservoirs and fluid flow in porous media is studied. DQM is a numerical method to solve nonlinear partial differential equations developed in the 1970s based on the integral quadrature. In the DQM model, partial derivatives of a function in one coordinate direction are set to the linear sum of weighted values of the function at all points along that direction. DQM has a simple formulation, low computational cost, and high accuracy with respect to other conventional numerical methods, employed frequently in various engineering fields. Fluid motion in a porous hydrocarbon reservoir is governed by partial differential equations. Several numerical methods have been used so far to solve these equations. In this study, differential quadrature method is used to solve the governing equations. For this purpose, several different flow simulations in a porous hydrocarbon's reservoir (including one-and-two-dimensional problems, compressible and incompressible stones, etc.) are considered. The obtained results and their degree of accuracy are compared with the already available analytical and numerical data found in the literature, and on that basis, it is concluded that DQM generates accurate results, is very easy to formulate and operate, does not need large mesh size, and is very time-efficient
مطالعهی آزمایشگاهی الگوی آبشستگی ناشی از استقرار پایههای دوتایی همگرا و واگرا و همراستا با جریان در موقعیتهای مختلف قوس ۱۸۰ درجه
No full textOne of the issues in river engineering is bridge protection in a way that bridges suffer the minimum damage during a flood. In many cases, due to the limitations, bridges are constructed on a river bend. The purpose of this research is to investigate the effect of constructing convergent and divergent (V-shaped \& A-shaped) coupled bridge piers and their position in parallel to the flow on a steep 180-degree bend bed topography. This research was performed on a laboratory channel at Persian Gulf University of Bushehr, Iran. The channel has a width of 1 meter, and a steep bend with a central radius to channel width ratio of 2 and a 180-degree bend. In the upstream and downstream of the bed, there are direct routes with lengths of 6.5 and 5.1 meters, respectively. For the experiments, PVC piers with 5 cm diameter a 21-degree angle to the vertical axis, materials with an average diameter of 1.5 mm and standard deviation of 1.14 were used. All the experiments were performed with flow velocity to critical velocity ratio of 0.98 (U/Uc=0.98) and constant depth of 18 cm at the beginning of the bend and 70 l/s discharge. The results show that the maximum depth of the scour hole occurs adjacent to the V-shaped coupled piers established at the position of 90 degree. By changing the piers from V-shaped to A-shaped at 60 and 90 degrees positions, the maximum scour hole is transfered from the adjacency of the upstream pier to the adjacency of the downstream pier, and by changing the position of the piers from the bend's upstream towards the downstream, the development of the maximum scour hole decreases. The highest scour depths were measured in the main hole and the second scour hole and also the highest sedimentation were measured as 0.97, 0.93 and 0.58 times the flow depth at the starting point of the bend respectively. In this paper, the results are discussed and analyzed
