Description
The aeration system is responsible for supplying the required oxygen (from 5 to 85 kg per hour per aerator) and effective mixing. At low speeds, the aerator acts as a mixer, and as a result, the amount of oxygen entering the tank at the surface is minimal. And at high speed, the function of this system is to supply oxygen.
Biogest’s surface Aerators with the commercial name of CROWN was developed in cooperation with Technische Hochschule Darmstadt university for circulation and oxygen provision to the wastewater-activated sludge.
The CROWN surface aerator has been successfully installed in more than 150 plants due to its main characteristics as follows.
1) Intensive mixing in aeration tanks: according to the specific design that creates horizontal and vertical currents a complete mixing will be achieved.
CROWN OB 2500 |
CROWN OB 2000 |
CROWN OB 1600 |
CROWN OB 1200 |
CROWN OB 900 |
CROWN OB 750 |
|
VA 1.4301 |
Material |
|||||
85 |
52 |
31 |
18 |
8 |
5 |
Maximum Oxygen input (KgO2/h) |
45 |
37 |
22 |
11 |
5.5 |
3 |
Motor power(KW) |
2500 |
2000 |
1600 |
1200 |
900 |
750 |
Diameter of aerator (mm) |
998 |
832 |
720 |
600 |
400 |
333 |
Height of aerator (mm) |
24 |
20 |
16 |
14 |
10 |
8 |
Number of blades |
500 |
400 |
200 |
120 |
45 |
38 |
Aerator weight (Kg) |
19 |
19 |
15 |
11.5 |
9 |
8 |
Max. tank length |
6 |
5 |
4.5 |
4 |
3.5 |
2.5 |
Water level |
1 |
1 |
1 |
1 |
0.8 |
0.8 |
Freeboard (m) |
2250 |
1850 |
1100 |
550 |
275 |
150 |
Max. tank volume (m3) |
Combination of mixing (denitrification) and oxygen provision (nitrification) according to the operation of aerator in different speed, low speed for mixing and high speed to provide oxygen demand.
4) Completely steel construction
5) long lifetime without reduction of its efficiency due to the robust construction
6) low energy consumption
7) low maintenance, all required maintenance parts are located above water level so any required repair would be easy
Application in fixed and variable water levels is based on the following.
1- Fixed water level:
1-1- Lateral installation (installation near the wall), to ensure the needed mixing of tank’s content it is necessary to be complemented by a mixer.
1-2- Central installation, the aerator has to be installed on a bridge
2- Variable water level
2-1- Lateral installation (installation near the wall), to ensure the needed mixing of tank’s content it is necessary to be complemented by a mixer.
2-2- Central installation, the aerator has to be installed on a bridge
Important features of surface aeration:
- Oxygen input efficiency up to 2.8 kg / kWh
- Input capacity up to 308 kg per hour
- Made entirely of stainless steel
- Almost unlimited life while maintaining aeration efficiency due to its strong structure
- Concentrated mixing
- Low energy consumption
- Commissioning at different speeds and application in two modes of fixed and variable sewage level
Customized design:
Under consideration of project-related requirements, the standard scope of delivery of the CROWN surface aerator can be enlarged by several optional components. The main optional components are as follows:
1- Complementing by a crusher unit, the advantage is rejected of particulates which incoming with sewage which makes the requirement of pretreatment no more necessary.