Computational fluid dynamics in wastewater treatment.
نویسندگان
چکیده
The purpose of activated sludge systems is to remove the waste from the polluted water by means of microorganisms. Removing the waste appropriately is one aspect; removing the biosolids from the clean water is another challenge. Hence, the settling tank, in which bioflocs are separated from the liquid by gravity, is a crucial operation in biological wastewater treatment systems. If the settling tank fails, solids will be carried over the weirs into the river. The consequences are significant. Increased turbidity may restrict plant photosynthesis, and the increased oxygen demand may be detrimental for aquatic life. Mathematical models can be used in many ways to make the settling tanks work efficiently, i.e. they can be applied for control purposes, design, fundamental process understanding, etc... For each aim another model that differs in complexity is most appropriate (Ekama et al., 1997). In this paper only models for settling tank design will be discussed that consist of local elementary balances of mass, momentum and energy. They are referred to as computational fluid dynamics (CFD) models and describe the system twoand/or three-dimensionally. Building a good CFD model is very tedious and a lot of challenges are encountered. In this respect the article will summarize the different steps to be taken when setting up a CFD model.
منابع مشابه
Tamás Karches COMPUTATIONAL FLUID DYNAMICS IN WASTEWATER TREATMENT: REACTOR DESIGN AND INTENSIFICATION
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ورودعنوان ژورنال:
- Mededelingen
دوره 67 4 شماره
صفحات -
تاریخ انتشار 2002