The Gratt Surface Aerator is a fundamental piece of equipment in aerobic effluent treatment processes.
Its main function is to promote the efficient transfer of oxygen to the liquid medium, ensuring ideal conditions for the metabolism of the microorganisms responsible for the degradation of organic matter. More than agitation, the system ensures continuous and controlled oxygenation, accelerating treatment and increasing process efficiency.
Importance of Aeration in Effluent Treatment
Aeration is a critical step in biological treatment systems, as it maintains the rate of oxygen supply equal to or greater than that consumed by bacteria. This balance favors the formation of new microbial cells in the activated sludge process, in addition to helping in the oxidation and precipitation of undesirable compounds, such as dissolved iron and manganese. The process also contributes to the removal of gases and volatile substances responsible for unpleasant odors.
How does it work?
The Gratt surface aerator operates by downward flow and air aspiration.
A special helical-shaped propeller sucks air directly from the surface and introduces it into the liquid at a suitable depth through a tubular shaft. This movement creates a vacuum that induces the entry of oxygen, generating ideal turbulence to keep solids in suspension and optimize biological efficiency.
Advantages of the Gratt Surface Aerator
Engineering and Technical Design
The equipment is the result of dedicated engineering, with a scaled engine specifically for operation under aeration regime. The set is designed to work at the correct rotation, with precise balancing, eliminating vibrations that cause premature wear. Unlike conventional solutions, does not use a marine propeller, bushings or bearings subject to frequent failures.
Construction and Materials
The Gratt Surface Aerator is manufactured with a stainless steel tubular shaft AISI 304, ensuring high mechanical and corrosion resistance. The absence of bushings and bearings reduces wear and maintenance points. The GRP buoy provides excellent buoyancy, structural robustness and long service life even in aggressive environments.
Sizing and Model Choice
Defining the ideal model depends on data such as dimensions of the pond or tank, depth and characteristics of the organic load. With this information, it is possible to calculate the volume of oxygen required and correctly specify the power and configuration of the aerator, ensuring maximum performance with the lowest operating cost.
Applications
The Gratt Surface Aerator is recommended for industrial and domestic effluent treatment stations, aeration tanks in ETAs and ETEs, aerated lagoons, stabilization lagoons and activated sludge processes. It is also widely used in systems that require continuous oxygenation and efficient odor control.
Power Table – Gratt Surface Aerator
