scholarly journals Modeling settling tanks for water treatment using computational fluid dynamics

2015 ◽  
Vol 17 (5) ◽  
pp. 745-762 ◽  
Author(s):  
Anastasios Stamou ◽  
Anthoula Gkesouli
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Water Treatment ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Hydraulic Efficiency ◽  
Dynamics Model ◽  
Negative Effect ◽  
Settling Performance

A computational fluid dynamics model is presented for the calculation of the flow, suspended solids, and tracer concentration fields in the settling tanks of the water treatment plant of Aharnes, an important component of the water supply system of the greater area of Athens, Greece. The model is applied to investigate the expected negative effect of the wind on the hydraulic and settling performance of the tanks and to evaluate the improvement resulting from the installation of one and two baffles; the wind is modeled using a simple and very conservative approach that involves the setting of a constant horizontal flow velocity on the free surface. The model is calibrated and verified with field turbidity measurements. Calculations show that the effect of wind on the flow field and the hydraulic efficiency is strong, with the creation of massive re-circulation areas with intense mixing and high short circuiting; however, the effect of wind on the settling performance of the tanks is not pronounced. The removal efficiency of the tanks, which is 72.48% in calm conditions, is reduced to 68.07% for windy conditions; moreover, it increases to 70.00 and 71.04%, when one or two baffles are installed, respectively.

Application of computational fluid dynamics (CFD) to ozone contactor optimization

2006 ◽  
Vol 6 (4) ◽  
pp. 9-16 ◽  
Author(s):  
J. Li ◽  
J. Zhang ◽  
J. Miao ◽  
J. Ma ◽  
W. Dong
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Water Treatment ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Original Design ◽  
Computational Fluid Dynamics Cfd ◽  
Ozone Contactor

Many approaches have been used to model the performance and efficiency of ozone contactors based on some assumptions to characterize the backmixing in fluids. Recently, computational fluid dynamics (CFD) technique has been proposed to simulate and optimize ozone contactors by calculating residence time distribution of fluid. To improve the ozone contactor performance of Bijianshan Water Treatment Plant in Shenzhen in South China, CFD was used for simulation and development of new optimization measures. Results showed that the low depth/length ratio of the contactor chambers in the original design resulted in short circuiting and backmixing, with the T10/HRT being only 0.40. Installation of guide plates substantially reduced short circuiting and backmixing with a much higher T10/HRT (0.66), increased by 73% compared with the original design.

The Use of Computational Fluid Dynamics for Improving the Design and Operation of Water and Wastewater Treatment Plants

1999 ◽  
Vol 40 (4-5) ◽  
pp. 81-89 ◽  
Author(s):  
C. J. Brouckaert ◽  
C. A. Buckley
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wastewater Treatment ◽  
Potable Water ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Outer Wall ◽  
Water And Wastewater Treatment ◽  
Secondary Clarifier

Computational Fluid Dynamics (CFD) studies of a secondary clarifier at Durban's Northern Wastewater Treatment Works, and of a clarifier at the potable water treatment plant at Umzinto, a small town near Durban, have been undertaken with a view to improving their load capacities. In both cases the units are located in relatively old treatment plants, which face continually increasing loads due to population growth. Increasing the capacity of existing equipment, rather than installing new equipment, constitutes an efficient use of development capital. Although the two clarifiers have considerable design differences, the CFD studies indicated remarkably similar circulating flows, which concentrate up-flow near the outer wall of the clarifier in the region of the clarified water overflow weirs. Baffles were designed to disrupt the circulation so as to distribute up-flow over a wider area, thereby reducing the maximum vertical velocities. In the case of the wastewater secondary clarifier, the modification has been implemented, and evaluated in comparative tests involving an otherwise identical unmodified clarifier. In the case of the potable water clarifier, the modification has still to be implemented.

scholarly journals Improvement performance of secondary clarifiers by a computational fluid dynamics model

2011 ◽  
Vol 19 (4) ◽  
pp. 1-11 ◽  
Author(s):  
Ali Ghawi ◽  
J. Kriš
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wastewater Treatment ◽  
Chemical Oxygen Demand ◽  
Biochemical Oxygen Demand ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Design Parameters ◽  
Dynamics Model ◽  
Computational Fluid Dynamics Model

Improvement performance of secondary clarifiers by a computational fluid dynamics model Secondary clarifier is one of the most commonly used unit operations in wastewater treatment plants. It is customarily designed to achieve the separation of solids from biologically treated effluents through the clarification of biological solids and the thickening of sludge. As treatment plants receive increasingly high wastewater flows, conventional sedimentation tanks suffer from overloading problems, which result in poor performance. Modification of inlet baffles through the use of an energy dissipating inlet (EDI) was proposed to enhance the performance in the circular clarifiers at the Al-Dewanyia wastewater treatment plant. A 3-dimensional fully mass conservative clarifier model, based on modern computational fluid dynamics theory, was applied to evaluate the proposed tank modification and to estimate the maximum capacity of the existing and modified clarifiers. A Computational Fluid Dynamics (CFD) model was formulated to describe the tank is performance, and design parameters were obtained based on the experimental results. The study revealed that velocity and (suspended solids) SS is a better parameter than TS (total solids), (Biochemical Oxygen Demand) BOD, (Chemical Oxygen Demand) COD to evaluate the performance of sedimentation tanks and that the removal efficiencies of the suspended solids, biochemical oxygen demand, and chemical oxygen demand were higher in the baffle.

scholarly journals Experimental Process Identification for Industrial Water De-carbonization in Power Plants

2013 ◽  
Vol 3 (2) ◽  
pp. 343
Author(s):  
MSc. Lutfi Bina ◽  
Dr.Sc. Mile Stankovski ◽  
Dr.Sc. Goran Stojanovski ◽  
MSc. Dejan Davikovikj ◽  
Gent Bina
Keyword(s):  
Water Treatment ◽  
Power Plants ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Polluted Water ◽  
Process Identification ◽  
Highly Nonlinear ◽  
Negative Effect ◽  
Experimental Process ◽  
Steam Production

Water Treatment Plant (or WTP) is the most important part of the Power Plant, because it produces vital-water it needs for steam production. Power Plants are the biggest air, ground and groundwater pollutants. Bad water quality directly impacts machine duration. Polluted water from Water Treatment Plant has a negative effect on people, flora and fauna, thus better waste management programs should be put in place to eliminate this problem. In this paper we are going to present the de-carbonization process of raw water as a part of water treatment plant, within coal fired power plants. De-carbonizing water is a time consuming process. We are going to present an advanced method for process identification with big time delay. The results are compared and one of the most appropriate methods is selected as identification method for this process. Further research and possibilities in this area are going to be presented by the end of the paper.Progress in identifying the process by which we work in this paper may serve as a new way to identify highly nonlinear processes. The used algorithm for identification of the process that is outlined in this paper can be applied, and it will be the basis for the creation of the software for the application of microcomputer techniques. Here we are applying the relevant software which can be applied in the form of programming packages for identification. This has to do with passive identification methods.

A STUDY ON OPTIMIZATION OF WATER TREATMENT PLANT DESIGN FOR EFFICIENT REMOVAL OF SUSPENDED SOLIDS

2020 ◽  
Vol 8 (4) ◽  
pp. 17
Author(s):  
T. P. SREEJANI ◽  
RAO G. V. R. SRINIVASA ◽  
RAO K. BHUVANESWARA ◽  
P. V. R. SRAVYA ◽  
◽  
...  
Keyword(s):  
Water Treatment ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Plant Design ◽  
Efficient Removal
Sign in / Sign up

Export Citation Format

Share Document