AIR PREHEATER PERFORMANCE

Leakage Control Systems

The Right Sealing Approach
Starts With the Equipment.

LJUNGSTRÖM leakage control systems help control leakage in rotary air preheaters, supporting efficiency, stable operation, and equipment life.

Advanced acid gas control

BENEFITS
Why Leakage Control Matters
Air that leaks across an air preheater’s seals bypasses its intended path. Controlling that leakage helps protect efficiency and plant performance.
Reduce Wasted Fan Power
Leaking air is moved by the fans without reaching the combustion process. Reducing that bypass can lower unnecessary fan demand.
Protect Heat Recovery
Keeping air and flue gas in their intended paths helps the preheater perform its heat-recovery role more effectively.
Support Plant Operation
Lower air-to-gas leakage can help reduce the burden on the draft system and support more consistent APH performance.

OUR SOLUTIONS

Three Approaches,
Matched to Your Equipment
Leakage control is not one size fits all. The right approach depends on your air preheater’s configuration, operating conditions, and performance goals.

LJUNGSTRÖM combines knowledge of the equipment with regional experience to understand the demands at each site. That insight helps us recommend a fixed, open-close, or sensor-control sealing approach suited to the application.

Fixed Sector Plates

SIMPLE. ROBUST. PROVEN.

Stationary seal geometry designed for a defined running clearance across the operating range.

Open-Close

TWO POSITIONS. FLEXIBLE OPERATION.

Two defined seal positions based on operating load, helping to optimize clearance during high and low load conditions.

Sensor-Control

CONTINUOUS. RESPONSIVE. PRECISE.

Continuous seal movement based on physical rotor position, maintaining optimal clearance throughout operation.

REAL-WORLD RESULTS

Measured Leakage Reduction in a Reference Installation

Reference project: 500 MW-class coal-fired unit with a 1x34-VI-2000(RT) rotary air heater. Leakage rates were measured for three sealing configurations.

Compared with standard seals

−53%
Leakage with SDU 10.2% → 4.8%
−59%
Leakage with SDS 10.2% → 4.2%

Results from this reference installation. Performance varies by equipment and operating conditions.

Find the Right Sealing Approach for Your APH

Our experts can help evaluate your air preheater and recommend the leakage control solution suited to your equipment and goals.

Request an Evaluation