Inverted umbrella type surface aerator

The HDS (High Power) inverted umbrella surface aerator is divided into three specification series: HDS350, HDS375, and HDS400. It is a new type of sewage treatment equipment with strong flow pushing ability, high oxygen filling capacity, and strong mixing and stirring effect. It is widely used for the treatment of industrial wastewater and urban domestic wastewater in industries such as petroleum, chemical, printing and dyeing, leather, medicine, papermaking, food, and gas. This equipment is not only suitable for aeration of sewage in activated sludge process, but also for aeration in rivers and oxidation ponds, especially suitable for use in Karusel oxidation ditch (multiple parallel oxidation ditches).

2、 Example of working principle and model of inverted umbrella surface aerator

Under the rotating propulsion of the impeller, sewage is thrown out from the edge of the impeller, forming a water curtain and trapping a large amount of air; The impeller expands in a conical shape from bottom to top, promoting the circulation of sewage up and down. The sewage is thoroughly mixed, and the liquid level is constantly updated; The bottom and back of the impeller form negative pressure due to the flow of water, which sucks in air. Therefore, sewage can mix with air over a large area, and oxygen quickly dissolves into the sewage, completing the oxygenation of the sewage and achieving the purification effect. At the same time, the powerful force drives a large amount of water flow, thereby achieving the effect of pushing flow.
3、 Structure and Characteristics

1. The HDS (high-power) inverted umbrella type surface aerator is mainly composed of a motor, gearbox, lubrication system, lifting platform, inverted umbrella seat, inverted umbrella impeller, electric control system, and other parts. The whole machine is a vertical structure, occupying a small area and not easily eroded by splashing sewage.
   Motor: Adopting Y series three-phase asynchronous motor, outdoor type, efficient, low-noise, vertical moisture-proof structure, installed on the gearbox at a high position, not easily corroded by splashing sewage and exhaust gas. At the same time, in order to achieve optimal oxygenation power efficiency, a variable frequency device can be equipped for variable frequency speed regulation and automatically controlled through a computer.
2. Gearbox: Vertical structure, three-stage cylindrical helical gear transmission. The gears are made of high-quality heat treated and ground into shape, with hard tooth surfaces, high precision, smooth operation, high transmission efficiency, low vibration, low noise, and not easy to leak oil. The designed service life exceeds ten years, especially since the output shaft can rotate in both directions, one gearbox is equivalent to two uses. The connection between the motor and the gearbox is centered through the motor seat and coupling, without the need for on-site adjustment, with high transmission efficiency, no impact, and low noise.
3. Lubrication system: adopts forced circulation and natural cooling lubrication system. The lubrication gear pump is directly installed on the output shaft of the gearbox, with good lubrication effect and safe and reliable structure.
4. Lifting platform: The lifting structure is a flat plate type, with an upper gearbox and a lower impeller spindle, supported by six screws on the workbench. By adjusting the nuts fixed on the six bolts, the height of the lifting platform can be changed, thereby adjusting the immersion depth of the impeller to obtain the required oxygen filling amount for the process. The lifting stroke of the impeller is ± 100mm.
5. Inverted umbrella seat: It adopts a sleeve floating shaft structure to connect the inverted umbrella shaft and the gearbox, which can achieve automatic centering and easy disassembly. At the same time, as the gearbox is not subjected to axial force, it also avoids vibration and noise caused by eccentricity due to hydraulic imbalance during impeller rotation.
6. Inverted umbrella impeller: a straight blade structure made of high-quality carbon steel welded into shape, and subjected to balance correction, shaping, and rust removal. It has strong radial flow pushing ability, wide complete mixing area, high power efficiency, large oxygenation ability, no fouling or blockage, excellent self-cleaning performance, and can rotate in both directions.
7. Electric control system: The constant speed inverted umbrella surface aerator is equipped with a pressure reducing starting cabinet, while the speed regulating inverted umbrella surface aerator is equipped with a variable frequency control cabinet, providing stepless speed regulation, a wide speed range, simple operation, high degree of automation, and good energy-saving effect; At the same time, PLC interfaces can be configured according to user requirements. Additionally, users can configure control cabinets or dual speed motors according to their own needs to adjust the impeller speed, in order to obtain the required oxygen filling amount for the process and save energy consumption.
8. For more detailed instructions, please refer to the accompanying technical documentation of the device.

4、 Specifications and technical parameters

Note: The oxygen content in this table is based on standard atmospheric conditions and 20 ℃ clean water conditions, with approximately 80-85% in wastewater.

5、 Design suggestions for aeration tank

1. Ordinary aeration tank: It can be built together or separately as a circular or square aeration tank, and the form and size are determined by the designer themselves. Suggestion:
   1. Circular pool: The ratio of impeller diameter to pool diameter is 1:4.5-7, and the median value should be taken.
   2. Square pool: The ratio of impeller diameter to pool edge length is 1:4-7, and the median value should be taken.
   3. The water depth is less than 3 times the diameter of the impeller, usually taken as 1.5 times the diameter of the impeller.
   4. The required power density for a fully mixed aeration tank should generally not be less than 25W/m3.
2. Oxidation ditch: The ditch width is about 2.2-2.4 times the diameter of the impeller, and the median value should be taken; The depth of the ditch is about 0.5 times the width of the ditch. The power density of the oxidation ditch should not be less than 15W/m3, with a suitable power of 20W/m3. be careful:
   1. It is not advisable to set up columns in the oxidation ditch. If necessary, the distance from the column to the edge of the impeller should be greater than the diameter of the impeller and be cylindrical.
   2. The distance between the partition wall in the oxidation ditch and the edge of the impeller should be between 0.04 and 0.08 impeller diameters.
   3. If there is no guide wall installed at the aerator, the center distance of the inverted umbrella impeller should be offset by 0.08-0.1 towards the outlet direction, and the distance between the impellers should be appropriate.
   4. The distance between the bottom of the platform beam and the designed water surface should be greater than 800mm.
3. Attention should be paid when placing an order: the inverted umbrella type surface aerator has a distinction between forward and reverse rotation, which should be clearly specified in the engineering design. When rotating clockwise, the foundation should be adjusted accordingly according to the attached diagram provided by our company.
   1. The net distance from the bottom to the water surface should be greater than 700mm.
   2. The distance between the partition wall in the oxidation ditch and the edge of the impeller should be 0.05-0.1 impeller diameter. If no diversion wall is set up, the center distance of the inverted umbrella impeller should be offset by 0.1 impeller diameter towards the outlet direction to facilitate water flow.
4. Attention should be paid when placing an order: the inverted umbrella type surface aerator has a distinction between forward and reverse rotation, which should be clearly specified in the engineering design. When rotating clockwise, the foundation should be adjusted accordingly according to the attached diagram provided by our company. When placing an order, the number of units in both forward and reverse directions should be clearly specified.