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Rapid turbine aerators
| Principle : These are surface aerators, which float, composed of a more or less sealed motor depending on the model and a float and grill which protect the propeller or turbine. The propeller or turbine is connected directly to the motor and pumps and projects water onto a cone, optimising its dispersion. There are mono-jet or double-jet systems (the mono-jet croates a current in the tank). The propeller must be isolated from the fish (by a grill) which therefore implies a reversible motor to unclogthe protection grill a process that does not dispence with manual cleaning by brush or pressure jet. The depth of pumping is adjustable ta avoid stirring up the debris on the bottom of the tank. |
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Technical characteristics : The power varies from 0.25 - 2 HP as required. The gross specific supply is around 1.2 kg/O2 per kWh consumed. Standard efficiency (SAE) is between 0.73 and 1.35 kg O2 / kWh. Efficiency : In general, the efficiency of these aerators is limited by the poor water circulation. For this reason, it is always the same water which is recycled and, as the rate of oxygen transfer decreases when the content approaches saturation, the efficiency decreases the longer they run. Surface turbines can also bring about a variation in the water temperature depending on the temperature of the surrounding atmosphere. |
Rapid turbine aerators on a caisson
| This Italian concept manages to regulate its diffusion depth by superposing caissons on top of each other. There are two models with motors allowing either a flow of 2000 l/min, or 3200 l/min. |
Slow Turbine Aerators
| Principle : Identical in concept to the fast turbines, with or without an immersed motor, and protected by a cover. The slow turbine aerators are the speed reducing mechanism of the engine, they do not project water, but create bubbling under the device. Efficiency : These machines cannot be blocked as they do not posses a grill. They are much quieter than the fast turbines. |
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To contact AQUALOG |
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Vertical Aerators
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Vertical aerators in hot galvanised steel are equipped with a cast aluminium propeller enclosed in a grate. Electric motor of 2 HP power Performance: 9000 l/min. |
Aerator with blades
| Principle : Aerators with blades are composed of an axle equipped with blades driven by a motor coupled to a reducer. The whole set-up is fixed to a trame equipped with floats. The power vanes between 0.3 and 15 HP. The shape of the propeller is very important and has an influence on the output (SAE). In ponds, this type of aerator can work with the power provided by a tractor. These devices cannot become clugged and they bring about a good mixing of the water mass. Standard efficiency is 1.5 kg O2/kWh. This type of aerator with blades is of hot galvanised steel. It is equipped with a 2HP electric motor and posseses a reduction gear. Performance: 4000/4500 l/min. |
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Aerators with blades mounted on a plastic body |
| Water aerators with wheels An aerator with wheels in hot galvanised steel. Equipped with a 2HP electric motor and a reduction gear. Performance: 4500 l/min. |
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To contact AQUALOG |
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Surface Hydro-ejectors
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Principle : A pump pumps in water through a constricted area, creating a depression to suck in air or oxygen, by a venturi effect. Venturi aerator creates a horizontal water stream with air injection. This device has the characteristic of diffusing very small air bubbles in the water, allowing better transfer of oxygen. This type of device has a SAE cf 1.29 to 4 kg of O2/kWh. |
| Venturi effect principle: A pump forces water through a bottleneck, where a zone of low pressure is created that is used to suck air or oxygen into the water. |
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Unifloat surface Hydro-ejectors
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Mounted on a unifloat, the device is an electric motor-driven propeller aerator which induces the flow of atmospheric air down a hollow shaft below the surface of the water. The propeller moves at high velocity and creates a submerged horizontal flow pattern. The result is very high oxygen dispersion and good circulation. Independent tests by a major USA university showed that a 2HP aspirator aerator thoroughly mixed and circulated the water in a one-acre pond (0.4 ha) in eight minutes. There were no dead spots either horizontally or vertically. |
Immersed hydro-ejectors
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This system consists of a submersed pump on which is fixed, with the aid of a tank, one or more hydro-ejectors. Principle : The principle of the hydro-ejector is as follows: - the flow of water created by the pump is directed towards the hydro-ejector This flow enters the body of the ejector via the duct. At this point, the flow rate is increased so as to create a strong depression via an aspiration tube, the air is introduced into the depression chamber at a speed sufficient to be then mixed with the water pumped into the mixing tube. The diffuser reinforces this effect by slowing down the speed of flow. Other systems lighter than the previous one, are also composed of an immersed pump and a venturi system allowing circulation without a supplementary energy supply. In this way, the water is enriched with air and pure oxygen. This apparatus is devised with the aim of supplying already-oxygenated and disturbed water in more economically and best conditions, to carry out the dissolution process in a faster way and to transform the unwanted gases into small bubbles before eliminating them. |
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Jet streamer
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When water is forced through the water jet pump, water jet is generated at the pump outlet. Simultaneously, suction flow is generated at the jet pump inlet due to negative pressure, and accompanies the driving water through the outlet. The water jet entrains the surrounding water to push it through the cylinder. As a result, the discharge at the cylinder mouth is much greater than the volume of pumped water alone. Features: - Energy saving - Long-term maintenance-free underwater components - Flexible system arrangement for various needs and applications - No negative influence on regional ecosystems - No dredging of sludge - Optional installation of aeration equipment - Optional utilisation for driving water for fountains |
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Aqualog
Bouée Borha
Corniche du Bois Sacré
Marépolis Est
83500 La Seyne sur Mer
Tél. : 04 94 10 26 26
Fax : 04 94 10 26 30
