The Need to Supply Oxygen to Water to Support the Life of Water Treating Microorganism The use of High Power in other Aerating Systems The Need to Generate Bubbles or Air Balls without Cavitation to the Aerator
water in the upper tank, d
a
is tested at several depth of 410 mm, 450 mm, 510 mm, 580 mm and 700 mm. The results of the experiment found that the optimum height of
plunging of the water jet, H is at 330 mm and the optimum angle of water jet, and
with respect to the horizontal plane are 50
o
at inception point and 56
o
at impact point at the nozzle and at the lower tank water surface respectively. Optimum diameter of the
plunging jet is 19 mm while the optimum depth of lower water tank is 190 mm and
finally the optimum depth of upper water in the upper tank is at 515 mm. The results obtained in experimental study is then validated by using computer simulation program,
CFD FLUENT and test on the prototype based on the optimum parameters. The optimum geometrical parameters obtained and validated above are used as the basis of the
new design of an efficient plunging water jet based cascade aerator for the post aeration process of treated water supply.
Keywords: br0kenbr0kenCascade, Aerator, Dissolved Oxygen, Efficient oxygen transfer
1 Introduction
Since the last decade, water aerating system has been evolving in terms of the methods and conventional technology, where the modifications are done to optimize the factors or parameters that
affect the efficiency of the system. Cascade aerator is usually used in the post treatment of drinking water widely. It consisted by a series of waterfall on a concrete ladder using the potential energy of the
gravitational pull of the water at the water inlet of the system. The cascade aerating depends on the early level of dissolved oxygen, the concentration of dissolved oxygen that is needed and the
temperature of the treated water.
More research has to be done cascade aerator to design a cascade aerator that is highly efficient to benefit the powers of the gravity that is not only cheap, but also free and flexible. The factor that
makes the cascade aerator not so popular amongst it is the emergence of the mechanical aerator that has a high SOTR Standardized Oxygen Transfer Rate and has made the technology of the cascade aerator
that is currently available not profitable to be improved in terms of incentive and innovatively Koduri Barkdoll 2003. Other factors will be discussed in the following sections.
2 Research Objectives
The objective of this research is to develop a cascade aerator that will be represented by a group of equations or general formula to design a universal cascade aerator that is efficient. This will be done in
all aspects that include theoretical research and also laboratory research and a compatibility comparison will be done on the findings of the previous research. The optimization research is done on the first
geometry cascade fall ladder only. While the geometry of the subsequent cascade falls are repetitions of the optimal first ladder cascade fall geometry where the efficiency has been optimized.
3 Problem Statement
Issues and problem that contribute to the extended research on the cascade aerator: