The ecological quality of water depends largely on the amount of oxygen that the water can hold. The higher the level of dissolved oxygen, the better the quality of a water system. By measuring dissolved oxygen, scientists determine the quality of water and health of an ecosystem. Oxygen enters water by entrainment of air bubbles. Many industrial and environmental processes involve the aeration of a liquid by such entrainment of air bubbles. Venturi aeration is a method of aeration that has become popular in recent years. When a minimal amount of differential pressure exists between the inlet and outlet sides of a venturi tube, a vacuum (air suction) occurs at the suction holes of the venturi tube. The present paper describes the effect of Reynolds Number, air inlet hole diameter, inlet diameter, pipe length, and angle of pipe downstream of the venturi tube, on the air injection rate. It is observed from the results that venturi tubes have high air injection efficiencies. Therefore, venturi tubes can be used as highly effective aerators in ponds, lakes, fish hatcheries, water treatment plants, etc.
"Recently, Baylar and Emiroglu (2003), Emiroglu and Baylar (2003), Laksitanonta and Singh (2003 and 2004), Baylar et al. (2005), Ozkan et al. (2006), Baylar and Ozkan (2006), Zhu et al. (2007) and Baylar et al. (2007a-b, 2009, 2010) have studied the use of venturi tubes in aeration systems. This paper describes an experimental investigation into air injection efficiency of venturi tubes, and in particular, the effect of air inlet hole diameter on air injection efficiency. "
[Show abstract][Hide abstract] ABSTRACT: The oxygen concentration in water is a prime indicator of the water quality for human use as well as for the aquatic biota.
The physical process of oxygen transfer or oxygen absorption from the atmosphere acts to replenish the used oxygen. This process
is termed re-aeration or aeration. Venturi aeration is a method of aeration that has become popular in recent years. A venturi
tube allows air bubbles to be inserted into flowing water from air inlet holes and so increases oxygen levels in the water.
In the present study, a series of experiments on venturi tubes were conducted to investigate the effect of air inlet hole
diameter on air injection. It was observed from the results that air inlet hole diameter on venturi tube played a significant
role in air injection and there was an optimal diameter that maximizes air injection. Moreover, a multiple non-linear regression
equation was obtained for venturi tubes relating air flow and water flow to Reynolds number, inlet diameter and air inlet
Keywordsaeration-air injection-venturi-water quality
"Os sistemas de autoaspiração de ar são utilizados para promover a oxigenação da água; trata-se de um método que se baseia nos princípios do tubo de Venturi e se utiliza de um ejetor para misturar o oxigênio do ar com a água. Os ejetores são equipamentos capazes de transformar a energia de pressão do fluido primário em energia de velocidade que, por sua vez, poderá atingir um nível crítico que induz à formação de vácuo na seção de contração do Venturi, realizando a sucção do ar atmosférico através de um vaso paralelo ao escoamento (Teixeira, 1999; Baylar et al., 2007a.; Baylar et al., 2009). "
[Show abstract][Hide abstract] ABSTRACT: RESUMO Na confecção deste trabalho se utilizou a metodologia de superfície de resposta para otimizar o efeito do número de Reynolds, tempo de floculação e concentração de hipoclorito de sódio sobre a oxidação/floculação do ferro presente em águas subterrâneas em um sistema de aeração com autoaspiração de ar. O sistema se compunha de um vaso tipo Ventu-ri, acoplado a um tubo de mistura para promover a oxigenação da água através da sucção do ar atmosférico. O mapea-mento hidrodinâmico permitiu verificar as condições de operação no qual o sistema apresentou melhor eficiência de sucção de ar e menor consumo de energia, além de compará-las com as melhores condições a campo. Os resultados observados demonstraram que foi possível a remoção de 98,7% do ferro presente (residual ferro de 0,06 mg L -1) quando o sistema operou com número de Reynolds no estrangulamento do Venturi de 5,39 x 10 4 , concentrações de hipoclorito de sódio de 38,4 mg L -1 e tempo de floculação 30 min. A metodologia de superfície de resposta foi satisfatória e permi-tiu otimizar as variáveis operacionais citadas. Palavras-chave: aeração, águas subterrâneas, metodologia de superfície de resposta, remoção de ferro Optimization of auto-aspiration aeration system type Venturi for the treatment of ferruginous water ABSTRACT In this study the response surface methodology was used to optimize the effect of Reynolds number, flocculation time and sodium hypochlorite concentration on the iron oxidation/flocculation present in groundwaters in an aeration system with air auto-aspiration. This system was composed of a recipient type Venturi coupled to a mixture tube to promote the oxygenation of the water through the suction of the atmospheric air. The hydrodynamic mapping allowed the verification of the operation conditions in which the system presented the best air suction efficiency and energy consumption, and the comparison of the best field conditions. The observed results demonstrated that it was possible to remove 98.7% of present iron (residual iron of 0.06 mg L -1) when the system operated with Reynolds number of 5.39 x 10 4 , sodium hypochlorite concentrations of 38.4 mg L -1 and flocculation time of 30 min. The response surface methodology was satisfactory and allowed for the optimization of the mentioned operational variables.
[Show abstract][Hide abstract] ABSTRACT: Dissolved oxygen is one of the most important water quality parameters. Aeration improves the water quality by maintaining good dissolved oxygen levels in water. Dissolved oxygen enters water by entrainment of air bubbles. A method of aeration that has become popular in recent years is the venturi aeration. In the present paper, experimental studies were conducted to investigate the effect of the location of the air hole in venturi tubes upon air injection. It was observed from the results that the location of the air hole playes a significant role for the air injection. The optimal air hole location that maximized the air injection in venturi aerators was determined.
CLEAN - Soil Air Water 06/2007; 35(3):246 - 249. DOI:10.1002/clen.200700026 · 1.95 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.