Selecting the right submersible mixer is a complex task; the correctness of the selection directly affects the normal operation of the equipment. The principle of selection should be to ensure the mixer performs full mixing functions within an appropriate volume, usually determined by flow rate.
Usage:
QJB TypeSubmersible mixerIt can be divided into two major series: mixed agitation and low-speed plug flow.
The Mixed Series Agitators are suitable for mixing suspended liquid in wastewater treatment plants and industrial processes.
Low-speed propeller mixers are suitable for aeration tanks in industrial and urban sewage treatment plants. They generate strong water currents with low tangential flow, which can be used to create water currents for recirculation and stages like nitrification, denitrification, and phosphorus removal.
FQJB Type Buoyant FloatSubmersible mixer
The FQJB-type Submersible Mixing Pump is a modified version of the standard submersible mixing pump, enhanced with a stainless steel buoyant float. The specific model selection follows the QJB-type submersible mixing pump specifications.
Application Scope:
The mixer should be able to operate continuously under the following conditions:
1. Medium temperature not to exceed 40°C.
2. The medium's pH value is between 5~9.
3. Liquid density not exceeding 1150 kg/m³.
4. Long-term dive operations, with dive depths typically not exceeding 20 meters.
Key Points to Note:
Submersible mixers must be fully submerged in water for operation; they cannot be used in environments with flammable, explosive, or highly corrosive liquids. Steel expansion bolts must be securely fastened according to specifications, and the cables must be tightened and securely fastened after installation.
Propellers of the diving propeller are all made of polyurethane material, equipped with a bevel gear box reducer.
Performance Features:
1. Compact structure, simple operation and maintenance, easy installation and inspection, and long service life.
2. The impeller features a rational hydraulic design structure, with swept-back blades that possess self-cleaning capabilities, preventing debris entanglement and blockages.
3. Mixing with the aeration system can significantly reduce energy consumption, increase oxygenation levels, and effectively prevent sedimentation.
4. Motor winding with F-grade insulation, IP68 protection rating, equipped with NSK/SKF bearings. The motor can be optionally fitted with a condensation prevention device. The motor utilizes an over-temperature protection system to ensure greater reliability in operation.
5. Two mechanical seals; the mechanical seals are sealed with silicon carbide material, and the rubber material is fluoroelastomer.
Model Representation Method:
Performance Parameters of Submersible Mixers:
The mixer operates at a rated voltage of 380V, a frequency of 50Hz, with a F-grade winding insulation, IP68 protection rating, and under working mode I conditions.
Installation Methods and Dimensions
Submersible mixerMultiple installation methods are available. Here, we offer more universal options for selection. Dimensions can be referred to in the table below. Our company can also provide special designs according to customer requirements.
Submersible mixer, submersible flow director dimensions
Installation System & Dimensions
Submersible mixers can be installed in various ways. Below are some of the more common methods, with others also available. These installations allow for quick assembly and disassembly of the submersible mixers without draining the pond's wastewater, ensuring both speed and safety.
FQJB Type Buoyant Submerged Mixing Pump Installation Site
Submersible mixers can also be installed with buoyant floats. The FQJB type buoyant float submersible mixer is a modified version of the standard submersible mixer, featuring stainless steel floats. It is primarily suitable for locations with uneven or non-firm pool bottoms, where bridge structures are also not feasible. It is specifically designed for wastewater treatment plants, without discharge of treated wastewater into rivers or other water bodies.
Selection Considerations:
Selecting a submersible mixer is a complex task, as the correctness of the selection directly affects the normal operation of the equipment. The principle of selection is to ensure that the mixer performs its mixing function fully within an appropriate volume, generally determined by the flow rate. According to the different process requirements of wastewater treatment plants, the flow rate of the mixer should be maintained between 0.15 to 0.3 m/s. A flow rate below 0.15 m/s will not achieve the desired push-mixing effect, and a flow rate exceeding 0.3 m/s will impact the process efficiency and cause waste. Therefore, before selecting, it is crucial to first determine the application site of the submersible mixer, such as a sewage pond, sludge pond, or biochemical pond. Next, consider the medium parameters, including suspended solids content, viscosity, temperature, and pH value. Also, take into account the pool's shape and water depth.
The required matching power for mixers is determined by the volume, density of the mixing liquid, and mixing depth. One or more mixers are selected based on the specific circumstances.
Hybrid Mixing Type:
1. Determine the sludge correction factor for the medium to be mixed based on Figure B1 or Table B1.
2. Determine the tank type correction coefficient for the mixing tank based on Figure B2 or Table B2.
3. Multiply the power required per cubic meter of fresh water by 5W, then by the sludge correction factor, and finally by the pond type correction factor to obtain the actual power required per cubic meter of the medium to be mixed. Multiply this by the volume of the medium to be mixed, and you get the total power required for the entire pond's mixed medium.
Low-speed Turbulence Generator
1. Determine the tank type correction factor for the mixing tank based on Figure B1 or Table B1.
2. Determine the sludge correction factor for the medium to be agitated based on Figure B2 or Table B2.
3. Determine the power consumption per unit volume based on the initial flow velocity y of the mixing medium, as indicated in Figure B3.
4. Calculate the blender's flow rate by multiplying the initial flow velocity of the mixing medium (y) by the cross-sectional area formed by the impeller rotation.
5. Multiply the flow rate of the mixer by the power consumption per unit flow, then by the sludge correction factor and the pond type correction factor to obtain the total power required for the entire pond medium.
Operating Conditions:
Compared to traditional vertical mixers, the service range of vertical mixers is limited. For large pools with high water volume and a wide aspect ratio, multiple vertical mixers are required to achieve proper mixing. However, the QJB type submersible mixer typically needs only 1-2 units to provide the required mixing effect. For open-air large pools, vertical mixers require the construction of a bridge framework for installation, whereas submersible mixers do not.
The QJB type submersible mixer's advantage lies in its ability to generate various flow directions. Different installation positions of the mixer yield multiple flow patterns, thereby creating a better flow effect in the pool and eliminating dead mixing zones. The required matching power for the submersible mixer is determined by the pool volume, medium density, viscosity, and depth of the mixing medium. Depending on the specific situation, one or more mixers should be selected.
To ensure energy-efficient operation of the submersible mixer across different pool types, refer to the following typical installation configurations.
