This guide covers everything you’re looking for about porous sparger such as working principle, function, benefits, features and classification, among other vital aspects.

So, if you want to be an expert in porous sparger, read this guide.

What is a Porous Sparger?

A porous sparger is a device that you can use to introduce gas into liquids in different process applications.

Porous sparger

Porous Sparger

What is the Function of a Porous Sparger?

The main function of a porous sparger is to efficiently introduce gas into liquids.

It has thousands of tiny pores which release numerous and tiny bubble of gas into the process liquid.

Porous spargers create more and smaller gas bubbles than any other type of sparger, hence increasing the surface area of gas/liquid contact.

As a result, they significantly lower the quantity of gas and time required to distribute the gas bubbles in the liquid.

What is the Working Principle of a Porous Sparger?

The porous sparger has a network of pores that produces numerous tiny bubbles when you pass pressurized gas through it.

The bubbles usually range between 0.5 to 10 micrometers and facilitate the efficient mass transfer of gas into liquids.

What Applications use a Porous Sparger?

You can use porous spargers in many industries to perform limitless operations in a wide range of applications.

These devices can be configured into different shapes and sizes to meet the demands and special needs of specific industries, processes, and applications.

Customized sizes and shapes can be fit with additional hardware to meet your special sparging conditions upon request.

Some of the processes and applications which require the use of a sparger include:

Porous sparger

Porous sparger

  • Carbonation: Introduction of carbon dioxide gas in beverages and beer for preservation
  • Aeration: Used for waste streams to meet biological oxygen demand
  • Bioremediation: Introduction of air to facilitate the proliferation of bacteria in waste treatment
  • Agitation: Use in diverse industries to facilitate efficient mixing of different liquids in a tank/vessel.
  • Fermentation: Sparging oxygen to enhance the growth of cells incubated under fermentation conditions
  • Oxygenation: Introduction of oxygen in fish ponds or aquarium
  • Ozonation: Sparging ozone for ultra-purification of water systems in pharmaceutical industries
  • Oxygen bleaching: Sparging oxygen to bleach pulp when manufacturing paper
  • Oxygen stripping: Used in the manufacture of edibles wines, juices, and edible oils where nitrogen sparging replace oxygen to enhance product longevity.
  • Hydrogenation: Sparging hydrogen for a broad range of hydrogen chemical reaction processes.
  • Dewatering: Important in the motor industry for the removal of entrained water from motor oil through sparging nitrogen.
  • Oil flotation: Removing water produced from oil wells through sparging in nitrogen or air.
  • Gas/liquid reactions: Used to improve process performance through sparging in oxygen, air, and other gases into the reactors.
  • pH control: Adjusting pH of a process stream or wastes through sparging ammonium gas or carbon dioxide.
  • Chlorine bleaching: Sparging chlorine to bleach pulp when manufacturing paper
  • Column floatation: Floatation of coal and separation of other solids through sperging air
  • Bulking: Introduction of nitrogen through sparging when bulking mustards or salad dressings.
  • Stripping volatiles: Removal of volatile organic compounds from waste streams through sparging air
  • Steam injection: Elimination of steam hammers and for direct heating through sparging steam.

When ordering the porous sparger for your application, you should select the sparger keeping in mind the type of process application you intend to use the sparger on.

Static spargers are used for tank/batch processes while dynamic spargers are designed for continuous applications in channels or pipelines.

What are the Components of a Porous Sparger?

Porous spargers come in a variety of designs such as perforated pipes, rings, frames, plates, and grids.

A porous sparger contains the sparger elements that produce the tiny bubbles and the attachment base that connects to the gas lines.

What are the Benefits of Using a High-efficiency Porous Sparger?

Using a quality and high-efficiency porous sparger will confer the following advantages:

  • High efficient and gentle transfer of a large quantity of gas into the liquid
  • Increased gas-liquid contact area
  • Lower volume and time required for the liquid to dissolve the gas
  • Reduced cost of operation due to less time and fluid volume
  • Cleanable and reusable
  • Enhanced rate of diffusion
  • Homogeneous and defined gas distribution
  • Reduced energy cost as a result of lower gas consumption

What Material can you use to Construct a Porous Sparger?

You can make your porous sparger from diverse types of construction materials.

The choice of the most suitable material will depend on the operating temperature and pressure, flow rate, corrosive effects of the fluid and gas, etc.

Generally, the majority of porous spargers are constructed using stainless steel (SS) 316L.

However, you request porous spargers constructed from polypropylene, sintered porous polyethylene, ceramics, glass, SS 304L, SS 347 SS, SS 430, Monel, Nickel, and other alloys.

Higher metal alloys like Hastelloy and Inconel are suitable for making porous spargers that operate under very high temperatures and aggressively corrosive conditions.

Porous metal spargers are stronger and more resistant to mechanical shock compared to other brittle materials which can break due to pressure.

You can also make your metal porous spargers using metal powder medium, metal fiber, or mesh for optimal economics.

What Types of Porous Spargers are there?

There are different types of porous spargers including:

· Static Porous Spargers

Static porous spargers are tank spargers used to introduce gas in liquids inside the tank or vessel.

You can use in-tank spargers in both batch and continuous processes in tanks that have or luck agitation.

A single porous sparger is usually sufficient for applications having a small tank.

For large tanks, you will need to manifold several porous spargers together in a linear or radial pattern.

You should use reinforcement when your tank is agitated.

· Dynamic Porous Spargers

Dynamic porous spargers are designed for use inside the pipeline.

They include:

  • In-line (Non-intrusive porous spargers
  • Sidestream porous spargers
  • Tangential (intrusive porous spargers)

What are the Features of a Good Porous Sparger?

The design of a good porous sparger should support the efficient distribution of gas into liquids at the most profitable production cost.

A high-quality porous sparger should possess the following characteristics to support a smooth transfer gas.

  • The material of construction should be non-corrosive and able to withstand extreme temperatures.
  • The design of the connectors and diameter of the sparger should meet the requirements of the application.
  • The material should withstand strong mechanical shocks
  • It should be compatible with additional hardware that might be required by some special types of applications.
  • It should be easy to install and replace
  • Should be easy to clean
  • The construction should a robust and high quality, all-welded construction
  • Uniform and fine pore sizes help in the mass distribution of tiny gas bubbles
  • Should have a broad range of media pore sizes to enable control of the bubble size
  • Should be available in a variety of standard and customized shapes and sizes
  • Should have sanitary furnishings if required

What Factors should you Consider when Designing a Porous Sparger?

Designing a customized porous sparger can be challenging if you fail to pay attention to the critical aspects which directly affect the effectiveness of the device.

You can follow these tips to help you fit your porous sparger to the needs of your application.

Gas sparger

Gas sparger

· Know your Goals and Application Details

You need to exhaustively outline the project output you expect to achieve and the details of your process application.

You should answer the following questions exhaustively.

  • What is the nature of your application? Are you carbonating, controlling pH, oxygenating, etc.?
  • What are the properties of your liquid and gas?
  • Is it a batch or continuous application?
  • What are the flow rates, pressure, and temperature of your system?
  • At what speed do you want the gas dissolved in the liquid?

· Work Out the Actual Volume of Gas you need to Disperse into the Liquid per Minute

You need to determine the actual cubic feet per minute (ACFM) that your sparger must supply into the liquid.

You can calculate this from the standard CFM and gas temperature and pressure.

· Determine the suitable Gas Exit Velocity

Determining the optimal gas velocity is essential and helps avoid the coalescing effect.

When gas coalesces, the bubbles grow in size, they lose the surface area, which increases the number of bubbles you require to achieve the desired distribution.

Consequently, you will use more gas and energy to achieve the same level of sparging.

Optimal velocity will help you conserve precious gas and save on energy cost as a result of reduced or no coalescing effect.

· Determine the Required Sparging Surface Area

The sparging surface area depends on multiple variables that are application-specific.

The aspects of the total surface area will influence the number, shape, and size of porous spargers your system will need.

You can consult a professional to help you determine the most suitable surface area for your application systems.

· Determining Geometry and Inclusions of the Sparger

This is the final step in designing a sparger and will take account of intricate details to meet the demands of your typical application.

Consider the most appropriate material to construct your porous spargers, the ideal media grade or pore sizes, the dimensions of the sparger, and the number of sparger elements required.

You can collaborate with our engineers to help you come up with the most efficient sparging elements at a reasonable budget.

What Determines the Size of a Porous Sparger Injector?

The size of a porous sparger injector is calculated based on the gas exit velocity.

You have to maintain the velocity below the maximum velocity for the continuous production of small bubble sizes.

Inline spargers located inside the pipelines can supports higher gas flowrates because the pipeline force can shear off bubbles from the injector.

The temperature and pressure of the liquid indirectly affect the sizing of the sparger since they influence the actual cubic feet per minute.

How does a Porous Sparger compare to other Types of Spargers?

Porous spargers have numerous beneficial properties compared to other types of spargers constructed from drilling pipes and other similar devices.

Porous spargers offer a smooth and efficient entrance of gas bubbles into the liquid through the creation of hundreds of thousands of fine bubbles.

As a result, you save a lot of money and time because the smooth mass transfer of gas reduces the volume and time required to dissolve the gas.

On the contrary, drilled pipe spargers and related devices offer a harsh and inefficient transfer of gas bubbles into the liquid.

The drilled sparger also produces large bubbles that increase the gas/liquid contact area and time required to dissolve a unit volume of gas.

Since the drilled gas spargers produce large bubbles, you will need a higher volume of gas that translates to the increased cost of production.

How Long can a Porous Sparger Last?

The on-stream service life of a porous sparger significantly varies depending on the material of construction and frequency of use.

Porous spargers constructed using all-metal construction materials can serve you for several years even under oxidizing environments at temperatures above 1450°F.

Porous sparger

Porous sparger

What Factors Affect the Performance of Porous Spargers?

The gas distribution efficiency of a porous sparger depends on numerous factors.

Some of the most critical factors that directly affect performance include:

  • The contact time between liquid and gas
  • The pressure of the gas
  • Temperature and pressure of the liquid
  • Size of the bubbles
  • The flow rate of gas compared to the flow rate of the liquid
  • The gas exit velocity
  • The actual ability of air compressor

What are the Benefits of Selecting a Porous Metal Sparger?

A porous metal sparger is more reliable with a proven performance record compared to spargers constructed using other materials.

You should consider using porous metal sparger because it provides the following distinct advantages:

  • Durable: Porous metal spargers can maintain useful service life for years of efficient sparging due to high structural integrity compared to other materials.
  • Strength: Porous spargers constructed from metallic material possess unmatched tensile strength which makes it conducive for applications that work under high flow rates and pressure.
  • Even porosity: Sintered metals favors the construction of porous spargers with uniform pore sizes that are evenly distributed. The availability of different grades of media with diverse pore sizes enables you to control the size of bubbles produced.
  • Reusability: You can restore the efficiency of a metallic porous sparger to near original condition through appropriately scheduled cleaning. You can clean the media using a back pulse technique or other suitable methods.
  • Thermal tolerance: Robust construction accompanied by perfectly welded seams and joints can withstand very high temperatures even under oxidizing atmospheric conditions.
  • Availability of wide choice of materials: Other than stainless steel, you can also choose from a wide variety of different types of metals that can meet the project specifications.

What Factors should you Consider when Choosing a Porous Sparger?

Selecting a porous sparger which has the most suitable properties helps attain the best sparging results at a reasonable cost of production.

When choosing a porous sparger, you should ensure that it meets the following properties.

  • The material of construction should be tolerant to the corrosive properties of the gas and process liquid.
  • The mean pore size should be capable of producing the desired sizes of bubbles.
  • The pores should be evenly distributed to enable fast and efficient mixing of gas into the process liquid
  • The material of construction should meet the cleanliness requirements for sanitary processes.
  • The sparger should have high tensile strength. It should be able to withstand high mechanical shock and maximum process temperatures.
  • You should also ensure that the porous sparger can withstand the operating pressure of your system

Can you Clean a Porous Sparger?

Yes, you can clean a metal porous sparger through different techniques.

The most suitable method will depend on the frequency of use and types of liquids and gases being processed.

How can you Test the Efficiency of a Porous Sparger?

You can determine the number and sizes of bubbles produced by a porous sparger through video analysis technique.

What Classification Methods are there for Spargers?

Porous media for the construction of porous spargers have different classification schemes.

The two most important classification schemes are the ASTM and ISO classification schemes.

Accordingly, both standards classify the porous material into four different classes graded as extra coarse, coarse, medium, and fine.

The classes depend on the pore size of the porous medium.

For instance, ISO 4793 standards classify extra course material from 100 to 250 microns, Course from 40 to 100 microns, medium from 16 to 40 microns, and fine from 10 to 16 microns.

On the other hand, ASMT classification is stricter.

The fine group has porous materials with pore sizes ranging from 4 to 5.5 microns, medium from 10 to 16 microns, coarse from 40 to 60 microns, and extra course from 10 to 220 microns.

What are the Issues Associated with Sparging?

Sparging steam for in-tank heating has shown some weaknesses in several process applications. These include:

  • Rough operations: Poor mixing and condensation can result in violent vibration and steam hammer.

Uncondensed steam will collapse when they contact a cold pipe that creates room for water to rush in and fill the void.

Pressure from the water will cause a pinging noise or steam hammer and vibration under severe conditions.

  • Energy loss: Direct energy loss can arise from uncondensed steam causing a reduction in efficiency and increased demand on the amount of steam required to heat the fluid.
  • Inefficient temperature control: When uncondensed steam escapes into the atmosphere or condense downstream, the steam energy does not register in the temperature controller. The condition can cause overheating of the liquid or variations in temperature.
  • Hot zones: The porous sparger can create a hot zone around it that might burn materials that are sensitive to heat.
  • Clogging: The pore in the sparger should be large enough to avoid being clogged by concentrated solids in columns bottom.

They should also withstand the long periods of operation demanded by industrial setups.

However, reducing the size of pores for smaller bubbles and preventing clogging is still problematic.

Therefore, these challenges may restrain the efficiency of porous spargers to small scale or laboratory tests rather than full-scale operations.

  • Shutdowns: You also have to shutdown the flotation operations to carry out servicing and repair and also to enable slurry to penetrate the air system.

As you can see, there are many factors you should consider when buying porous sparger.

The best part, this guide as makes everything simple and easy to understand.

For questions or inquiries about porous spargers, contact FilSon Filters now.