Sulfuric Acid Drying Tower Packing: Ceramic Berl Saddle vs Intalox Saddle

Sulfuric acid drying towers require random packing that can operate under strongly corrosive conditions while providing reliable gas-liquid contact and acceptable hydraulic performance.

In these towers, concentrated sulfuric acid flows downward through the packing while moist process gas or air flows upward. Water vapor is absorbed into the acid, reducing the moisture content of the gas before it enters the next process stage.

Ceramic random packing has historically been widely used in this service because of its corrosion resistance, temperature capability, and compatibility with concentrated sulfuric acid environments.

Two packing families commonly encountered in existing equipment are:

• Ceramic Berl Saddle
• Ceramic Intalox Saddle

Both can provide effective gas-liquid contact, but their geometry is different.

For a new tower or a retrofit project, the important question is not simply which saddle is newer.

The practical question is:

Should an existing sulfuric acid drying tower keep its Ceramic Berl Saddle, or is Ceramic Intalox Saddle a better hydraulic choice?

---

Why Sulfuric Acid Drying Towers Need Special Packing

A sulfuric acid drying tower is not an ordinary water scrubber.

The packing operates in contact with concentrated sulfuric acid, often continuously, while simultaneously handling a significant upward gas flow.

The packing must therefore provide several characteristics at the same time:

• strong acid resistance
• thermal stability
• adequate mechanical strength
• good liquid spreading
• sufficient wetted surface
• acceptable pressure drop
• reliable drainage
• long service life

Material compatibility is particularly important.

A packing that performs well hydraulically but cannot tolerate the acid environment is not a viable option.

This is one reason ceramic packing remains relevant in sulfuric acid tower service even though plastic and metallic random packings dominate many other applications.

---

1. What Is Ceramic Berl Saddle?

Ceramic Berl Saddle is one of the older saddle-type random packing geometries.

Its characteristic shape resembles a curved saddle, providing greater surface exposure than a simple cylindrical Raschig Ring.

Compared with older ring packing, the saddle geometry provides:

• more exposed surface
• fewer enclosed internal regions
• improved liquid spreading
• multiple gas-flow directions

For many decades, Berl Saddles were used in corrosive packed towers, including acid-handling equipment.

As a result, many existing sulfuric acid plants still contain Berl Saddle packing.

That makes Berl Saddle particularly important in maintenance and replacement projects, even if a newer geometry might be selected for a completely new tower.

---

2. What Is Ceramic Intalox Saddle?

Ceramic Intalox Saddle is a later saddle-type random packing developed to improve packing arrangement and hydraulic characteristics.

Its modified geometry generally creates a more open packed bed than traditional Berl Saddle designs.

The intended advantages include:

• improved gas and liquid flow passages
• reduced nesting between packing pieces
• more uniform random orientation
• good liquid redistribution
• favorable pressure-drop characteristics

For new packed-tower designs, Intalox Saddle is therefore often considered where the designer wants the chemical resistance of ceramic together with better bed hydraulics than older random packing geometries.

---

3. Why Ceramic Material Is Attractive in Concentrated Sulfuric Acid Service

The choice between Berl and Intalox Saddle is mainly a geometry question.

The decision to use ceramic is a material question.

Ceramic random packing can provide several advantages in concentrated acid applications.

Strong Chemical Resistance

Ceramic materials are resistant to many strongly acidic environments where ordinary metals or common plastics may be unsuitable.

Temperature Capability

Ceramic packing can tolerate temperatures significantly above the practical limits of many thermoplastic packings.

Surface Wettability

Ceramic surfaces can provide favorable liquid wetting characteristics, which can be useful where concentrated sulfuric acid must spread over the packing.

Long-Term Stability

Ceramic does not soften like thermoplastics at elevated temperature.

However, ceramic also has disadvantages:

• brittleness
• potential breakage during installation
• greater weight
• sensitivity to mechanical impact

These factors must be considered during tower loading and maintenance.

---

4. Berl Saddle vs Intalox Saddle: The Main Difference Is Bed Geometry

The two products may be manufactured from similar ceramic material, but their shape affects how the packed bed behaves.

Traditional Berl Saddles can interact and nest with neighboring pieces in ways that create somewhat less open flow paths.

Intalox-style geometry was developed partly to reduce this tendency.

In practical tower operation, packing geometry influences:

• void space
• gas-flow resistance
• liquid holdup
• pressure drop
• flooding tendency
• liquid spreading

Therefore, replacing Berl Saddle with Intalox Saddle is not merely a cosmetic change.

It can alter the hydraulic characteristics of the entire packed section.

---

5. Pressure Drop Can Favor the More Open Saddle Geometry

Sulfuric acid drying towers may handle large volumes of process gas.

Packed-bed pressure drop therefore matters.

Excessive resistance can:

• increase blower or compressor duty
• limit gas throughput
• reduce available hydraulic margin
• move the bed closer to loading or flooding

A more open saddle geometry can provide more space for upward gas movement.

For this reason, Ceramic Intalox Saddle may be worth evaluating when an existing Berl Saddle tower has:

• high packed-bed pressure drop
• limited gas capacity
• plans for increased production
• signs of early hydraulic loading

However, the packing geometry is not the only contributor to pressure drop.

The complete tower must also be checked.

---

6. Do Not Blame the Packing Before Checking the Tower Internals

An acid drying tower may contain several internal components that affect gas flow.

These can include:

• packing support
• liquid distributor
• acid collection system
• redistributor
• hold-down or bed limiter
• mist eliminator

If any of these components have insufficient open area or are partially blocked, the tower may experience excessive pressure loss even if the packing itself is acceptable.

Before changing from Berl Saddle to Intalox Saddle, determine where the pressure drop actually occurs.

Otherwise, a packing replacement may fail to solve the original problem.

---

7. Existing Berl Saddle Towers Do Not Automatically Need Upgrading

Many plants operate old packed towers successfully for decades.

If an existing Berl Saddle bed provides:

• acceptable drying performance
• acceptable pressure drop
• stable gas capacity
• reasonable maintenance intervals

then there may be no strong engineering reason to change packing geometry during routine replacement.

For a simple maintenance shutdown, like-for-like replacement can sometimes be the lowest-risk option.

This is especially true when:

• tower diameter is unchanged
• gas rate is unchanged
• acid circulation rate is unchanged
• drying performance is satisfactory
• original operating data are limited

Changing packing just because a newer geometry exists can introduce unnecessary uncertainty.

---

8. When Intalox Saddle Becomes More Attractive

A change to Ceramic Intalox Saddle becomes more logical when there is a clear operating objective.

Typical examples include:

Increasing Gas Throughput

If production is being expanded but tower diameter cannot be increased, a hydraulically more open packing may be worth evaluating.

Reducing Pressure Drop

If the existing Berl Saddle bed is a significant pressure-drop contributor, a different saddle geometry may provide additional operating margin.

Reducing Packing Nesting

A more open random arrangement can help avoid some of the hydraulic disadvantages associated with strongly nested packing pieces.

Building a New Tower

For a new design, there may be little reason to default automatically to an older Berl Saddle geometry if a more efficient modern ceramic saddle is available and supported by hydraulic data.

---

9. Packing Size Matters as Much as Saddle Type

A major selection mistake is comparing only:

Berl Saddle vs Intalox Saddle

while ignoring size.

Packing size affects:

• surface area
• void fraction
• pressure drop
• number of elements per cubic meter
• gas capacity
• liquid distribution
• fouling tolerance

Smaller ceramic packing typically provides more contact area but also creates more hydraulic resistance.

Larger packing generally provides more open passages and higher capacity but less contact area per unit packed volume.

Therefore, a retrofit comparison should evaluate:

packing family + packing size

together.

A large Intalox Saddle and a much smaller Berl Saddle cannot be compared on geometry alone.

---

10. Drying Performance Must Still Be Preserved

Lower pressure drop is valuable, but sulfuric acid drying towers have a process objective:

remove moisture from the gas.

The packing must provide sufficient gas-liquid contact for the acid to absorb the required water vapor.

Drying performance depends on more than packing geometry.

It also depends on:

• sulfuric acid concentration
• acid temperature
• acid circulation rate
• gas flow
• inlet moisture
• outlet moisture requirement
• packed-bed height
• liquid distribution

If packing is changed to a more open geometry, the engineer must confirm that adequate mass-transfer performance remains available.

The correct optimization is not:

minimum possible pressure drop

but:

required drying performance at acceptable pressure drop.

---

11. Acid Distribution Is Critical

Ceramic packing cannot compensate for a poor acid distributor.

If concentrated sulfuric acid does not enter the packed bed uniformly, some regions may receive too much liquid while others remain insufficiently wetted.

This can produce:

• uneven mass transfer
• local gas channeling
• reduced drying efficiency
• localized hydraulic loading

Large-diameter drying towers therefore require careful liquid-distribution design.

When an old tower is retrofitted, the distributor should be inspected along with the packing.

Changing Berl Saddle to Intalox Saddle while retaining a damaged or badly distributed acid feed system may deliver little benefit.

---

12. Ceramic Breakage Must Be Considered During Replacement

Ceramic packing has excellent chemical resistance but is brittle.

During tower maintenance, packing can be damaged by:

• uncontrolled dumping
• excessive drop height
• workers walking directly on the bed
• mechanical impact
• improper transportation

Broken ceramic pieces can:

• reduce effective void space
• increase pressure drop
• accumulate on the support grid
• create fines or fragments

Replacement installation should therefore control the loading method.

The packing support should also be inspected before a new ceramic bed is installed.

---

13. Support Grid Compatibility Matters

A new packing specification must remain compatible with the existing support.

The support grid openings must be small enough to retain the packing while maintaining sufficient open area for gas and liquid flow.

If a retrofit changes packing size substantially, check:

• support opening
• packing element minimum dimension
• support mechanical strength
• corrosion condition
• available free area

This is especially important when replacing an old Berl Saddle size with a different Intalox Saddle size.

---

14. What About Ceramic Raschig Rings?

Some older acid towers may also contain Ceramic Raschig Rings.

Compared with traditional Raschig Ring geometry, saddle-type packing generally provides a more favorable use of surface area and internal void space.

Therefore, a modernization project involving very old Raschig Ring packing may have a stronger reason to evaluate saddle-type alternatives.

But again, the replacement must be checked hydraulically.

Changing packing geometry affects:

• bed weight
• pressure drop
• capacity
• support loading
• liquid holdup
• packing volume

A direct volume-for-volume replacement should not be assumed automatically.

---

15. New Tower vs Retrofit: Different Decisions

For a new sulfuric acid drying tower, the designer has more freedom.

Tower diameter, packing type, support, distributor, packed height and acid circulation can be designed together.

In this situation, Ceramic Intalox Saddle may be an attractive starting point because of its more modern hydraulic geometry.

For a retrofit, however, the tower already exists.

The decision must consider:

• current packing
• actual operating performance
• existing support
• distributor
• gas rate
• acid rate
• available tower diameter
• available packed height

A retrofit should therefore solve a documented problem rather than simply follow a newer product preference.

---

16. Simple Selection Guide

---

17. Data Needed for a Replacement or Retrofit RFQ

For a sulfuric acid drying tower packing inquiry, useful information includes:

• tower internal diameter
• current packing type
• current packing size
• packed-bed height
• required packing volume
• sulfuric acid concentration
• acid operating temperature
• gas flow rate
• gas temperature
• operating pressure
• current pressure drop
• required drying performance
• existing distributor type
• packing support details
• tower drawings
• photographs of the existing packing

For older towers where the original specification has been lost, a physical packing sample or clear dimensional photographs can also be useful.

---

Final Selection Principle

Ceramic Berl Saddle and Ceramic Intalox Saddle can both be used in highly corrosive packed-tower environments such as sulfuric acid drying service.

The difference is mainly one of geometry and hydraulic behavior, not simply chemical resistance.

Berl Saddle remains relevant for:

proven legacy towers and like-for-like replacement.

Intalox Saddle becomes particularly attractive when the project requires:

improved hydraulic openness, reduced pressure drop, or increased gas capacity.

The correct decision therefore depends on whether the project is:

maintenance replacementorperformance improvement.

If the existing tower operates satisfactorily, changing packing geometry may be unnecessary.

If pressure drop or throughput is limiting operation, a more open ceramic saddle deserves a proper hydraulic evaluation.