Electric submersible agitator is a common device used in underwater applications. It is widely used in various underwater industries, such as wastewater treatment, offshore oil drilling, etc. It is used in different industries with different working depth ranges.Similarly, the factors that affect performance at different depths are also different.

Working Depth Range Of Electric Submersible Agitators

The operating depth range of electric submersible mixers varies depending on their design, manufacturing materials, and intended use. Generally, these devices can be divided into shallow water, medium water, and deep water mixers.

Shallow water mixers generally operate within a depth range of 10 meters and are commonly used in municipal wastewater treatment plants, small ponds, and agricultural applications. They are designed for relatively low pressure environments and are usually equipped with simpler sealing mechanisms.

Medium water mixers can effectively operate in water depths ranging from 10 to 50 meters and are suitable for large industrial wastewater treatment facilities, reservoirs, and some marine environments. They use more robust sealing systems and pressure-resistant components to cope with increased hydrostatic pressure.

Deep water mixers are designed for depths exceeding 50 meters, and some devices can operate at depths of 1,000 meters or more. These mixers are used in offshore oil and gas platforms, deep sea research, and seabed mining. They use advanced sealing technology, pressure-compensated motors, and high-strength materials to withstand extreme underwater environments.

When selecting an agitator, refer to the manufacturer's guidelines and consider other factors besides depth capability.

Factors Affecting The Working Depth Of Agitators

Various factors affect the operating depth and performance of electric submersible agitators underwater. These factors contribute to the selection of the right agitator and its long-term and efficient operation.

As the agitator sinks deeper, the hydrostatic pressure builds up, putting stress on all components, including the housing, seals, and internal mechanisms. For every 10 meters of water depth, the pressure increases by about 1 atmosphere (14.7 psi). In deep water areas, this pressure may pose a threat to the agitator structure and cause failure if it is not designed properly.

The increase in water pressure has a significant effect on the motor, shaft seal and electrical components of the agitator. The motor needs to be able to withstand pressure and maintain good lubrication under high pressure. Shaft seals need to both prevent water ingress and allow the shaft to rotate freely. As depth increases, more sophisticated sealing solutions are required to ensure that the internal components of the agitator are not damaged.

The sealing system of the agitator is crucial to its stable operation in deep water. Common mechanical seals form a barrier between a rotating shaft and a stationary housing and often contain multiple stages and exotic materials, such as silicon carbide or tungsten carbide, to handle high pressures and abrasive particles.

Another critical sealing component is the cable entry point. High-quality agitators use specially designed cable glands or potted cable entries to prevent water from entering the motor housing along the power cable. Some deep-water agitators also employ pressure-compensating systems that balance the internal pressure of the motor housing with the external water pressure, reducing stress on seals and components.

Material selection has a direct impact on sealing effectiveness. Elastomers in seals are carefully selected to resist degradation from prolonged exposure to water, chemicals, and high pressures. Fluoroelastomers and perfluoroelastomers are often used in deepwater applications due to their excellent chemical resistance and ability to maintain performance under extreme conditions.

When selecting a deepwater agitator, make sure the sealing system is rated for the expected operating depth. Regular maintenance and inspection of seals will help them achieve long-term, reliable operation in harsh underwater environments.

Application

Electric submersible agitators find use in a wide range of applications across various industries. The specific depth capabilities of these devices often determine their suitability for different scenarios.

Shallow-water applications (0-10 meters):

1. Municipal wastewater treatment plants: Agitators are used in aeration basins and mixing tanks to promote oxygen transfer and prevent solids settling.

2. Aquaculture: In fish farms and shrimp ponds, agitators help maintain water quality by ensuring proper circulation and oxygenation.

3. Stormwater retention basins: Agitators prevent stagnation and reduce the buildup of algae and odors in urban water management systems.

4. Agricultural lagoons: They assist in mixing and aerating livestock waste treatment ponds.

Medium-depth applications (10-50 meters):

1. Industrial wastewater treatment: Larger facilities dealing with more complex effluents often require deeper tanks with more powerful agitators.

2. Reservoirs and lakes: Agitators can be used to prevent stratification and improve water quality in deeper bodies of water.

3. Ports and harbors: They help maintain water quality and prevent sedimentation in deeper areas of maritime facilities.

4. Offshore aquaculture: As fish farming moves to open ocean environments, medium-depth agitators play a role in maintaining optimal conditions in sea cages.

Deep-water applications (50+ meters):

1. Offshore oil and gas platforms: Deep-water agitators are crucial in various processes, including drilling mud mixing, produced water treatment, and subsea chemical injection systems.

2. Deep-sea mining: As the industry explores mineral extraction from the ocean floor, agitators are used in processing and waste management systems at significant depths.

3. Oceanographic research: Scientists use specialized agitators to study deep-sea environments and conduct experiments at extreme depths.

4. Subsea oil and gas processing: As more processing moves to the seafloor, agitators play a role in various systems operating at depths of 1000 meters or more.

The technical requirements for deep-water mixers in these applications are particularly demanding. They must withstand extreme pressures, operate reliably for extended periods without maintenance, and often function in corrosive or chemically challenging environments. Materials such as super duplex stainless steel or titanium are often used for critical components to ensure durability.

Deep-water agitators also require specialized power and control systems. Long subsea power cables must be designed to minimize voltage drop over great distances. Remote monitoring and control capabilities are essential, allowing operators to adjust agitator performance from the surface or onshore control rooms.

In offshore oil and gas applications, agitators may need to meet specific industry standards such as those set by API (American Petroleum Institute) or DNV GL (Det Norske Veritas Germanischer Lloyd). These standards ensure that equipment can withstand the harsh conditions encountered in deep-sea environments and operate safely in potentially explosive atmospheres.

As technology advances and industries continue to explore deeper underwater environments, the demand for more capable and reliable submersible agitators grows. Manufacturers are continually innovating to meet these challenges, developing new materials, sealing technologies, and control systems to push the boundaries of what's possible in underwater mixing and agitation.

About Tianjin Kairun Pump Co., Ltd.

Tianjin Kairun Pump Co., Ltd. is a well-known manufacturer of electric submersible agitatorsand other pumping equipment. Our company's commitment to quality is reflected in its ISO 9001.Tianjin Kairun offers a range of products suitable for a variety of applications and depths. Our staff has the professional knowledge to provide you with suitable advice, you can contact us at catherine@kairunpump.com, we are always online.

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