Parkson Lamella Clarifier Replacement, Plate Packs & Upgrades

A Parkson lamella clarifier is an inclined plate settling system designed to remove suspended solids from wastewater.

Instead of relying on a large open tank, lamella clarifiers use stacked inclined plates to dramatically increase settling area.

• Wastewater enters after chemical treatment 
• Flow moves upward through inclined plates 
• Solids settle onto the plates 
• Sludge slides downward into a hopper 
• Clarified water exits over a weir 

This design allows:

• Higher flow rates 
• Smaller footprint 
• Improved solids removal

 Parkson helped popularize lamella clarifiers decades ago.

At the time, they offered major advantages over conventional clarifiers:

• Compact footprint 
• Increased surface area 
• Lower capital cost 
• Reliable operation 

Many of these systems are still in operation today.

While the technology is proven, many existing Parkson systems are now:

• 10–30+ years old 
• Operating under different wastewater conditions 
• Running beyond their original design capacity 

This leads to common issues:

Older designs often operate at shorter retention times (~20–25 minutes), which can allow solids to escape.

Over time:

• Plates clog 
• Flow paths become restricted 
• Effective settling area decreases 

Older inlet designs can cause:

• Short-circuiting 
• Uneven flow distribution 

Improper sludge removal can lead to:

• “Rat-holing” 
• Solids carryover 
• Re-entrainment

• Plate angle: 50–70° 
• Plate spacing: ~50 mm 
• Surface loading rate: 10–25 m/h  
• Retention time: ~20 minutes

Facilities are upgrading because:

• Regulations are stricter 
• Wastewater is more complex 
• Production volumes are higher 

Modern systems offer:

• Better clarity 
• Higher throughput 
• Lower maintenance

👉 Matching footprint
👉 Increasing performance
👉 Reducing operating issues

Options include:

• Direct replacement systems 
• Custom-built retrofits 
• High-efficiency plate packs

Caused by:

• High flow rates 
• Insufficient retention time 
• Plate fouling 

Many facilities using older Parkson lamella clarifiers experience issues such as sludge buildup,  and poor settling performance. These problems are often caused by shorter retention times, worn plate packs, or outdated designs.

Modern replacement systems are designed with improved retention time, optimized plate spacing, and better sludge removal to eliminate these issues.

Learn more about upgrading your system here:
parkson lamella clarifier 

Caused by:

• High flow rates 
• Insufficient retention time 
• Plate fouling 

Caused by:

• Inadequate blowdown 
• Poor hopper design
• Rat Holing

Caused by:

• Poor chemical treatment 
• Worn plates 
• Hydraulic overload

Caused by:

• Fouled plates 
• Outdated design