01 The Key Role of the Urea Pump in SCR Denitration Systems
Controlling nitrogen oxide (NOx) emissions from industrial flue gas has become an essential environmental challenge for various industries. SCR (Selective Catalytic Reduction) technology, as the most mature and widely used denitration method, relies heavily on the precise metering and stable delivery of urea solution. The urea pump, as the "heart" of the SCR system, directly impacts denitration efficiency, system stability, and operating costs. Choosing a suitable urea pump is not only a technical issue but also a guarantee of both economic benefits and environmental compliance.
02 Five Key Points for Selecting a Urea Pump
Basic principle of SCR: Urea solution is injected into flue gas at 200°C to 400°C using a magnetic drive pump, reducing NO and NO₂ to N₂ and water.
Sealing Performance: Zero Leakage is a Basic Requirement Urea solution is corrosive and prone to crystallization. Leakage can cause environmental pollution, system blockage, and catalyst failure. ➤ Recommendation: Choose a magnetically driven pump with a static seal design to eliminate leakage risks from dynamic seals. ➤ Avoid: Traditional mechanical seal pumps, which are prone to wear, have a short service life, and are unsuitable for urea media.
Self-Priming Capability and Dry-Run Resistance Urea pumps often need to draw liquid from low-lying storage tanks. Poor self-priming can lead to cavitation and flow interruption, affecting denitration efficiency. ➤ Recommendation: Select a pump with strong self-priming capability (4–5 meters in wet conditions, up to 8 meters in full-liquid conditions) and dry-run tolerance. ➤ Avoid: Pumps with limited self-priming that require priming for startup.
Pressure and Temperature Resistance SCR system operating pressure typically ranges from 5.5 to 9.5 Bar. The pump's pressure-bearing capacity should have a safety margin. ➤ Recommendation: Choose a pump with a pressure differential range within 15 bar and a temperature resistance range of -120°C to 150°C to adapt to extreme conditions. ➤ Avoid: Pumps with limited self-priming that require priming for startup.
Fluid Compatibility and Anti-Crystallization Capability Urea solution tends to crystallize at low temperatures. The pump's structure and materials must be corrosion-resistant and designed to prevent crystallization, with the ability to reverse-rotate to clear the pipeline after shutdown. ➤ Recommendation: Use pumps with gears made of high-performance polymers like PEEK and smooth flow paths to minimize crystallization buildup. ➤ Avoid: Pumps with metal gears or complex structures that retain residual liquid.
Service Life and Maintenance Costs Urea pumps are often used in continuous operation. Frequent replacements can severely impact system stability and operating costs. ➤ Recommendation: Opt for pumps with a service life >20,000 hours, simple structure, and easy maintenance. ➤ Avoid: Pumps with short lifespans requiring frequent seal or gear replacements.
03 Recommended Product: Suofu NP Series Micro Magnetic Gear Pump
Feature
Suofu NP Series Magnetic Gear Pump
Other Magnetic Gear Pumps
Mechanical Diaphragm Pumps
Sealing Method
Static seal, zero leakage
Static seal
Dynamic seal, prone to leakage
Pressure Differential
Up to 15 bar
Mostly <8 bar
Generally <10 bar
Self-Priming Capability
Strong, up to 20 bar, supports extended dry-running
Moderate, supports very short dry-running
Limited, requires priming
Service Life
Long, >20,000 hours
Generally <10,000 hours
10,000–20,000 hours
Pressure Fluctuation
None
None
Present
Tailored for SCR urea delivery applications, Suofu's NP Series Micro Magnetic Gear Pump offers the following advantages:
➤ Leak-Free: Magnetic drive, static seal structure ➤ High Pressure: Pressure differential up to 20 bar, suitable for 5.5–9.5 Bar operating conditions ➤ Strong Self-Priming: Dry-run self-priming, 4–5 meters in wet conditions, 8 meters in full-liquid conditions ➤ Wide Temperature Range: PEEK gears; while urea pump operating scenarios typically require -40°C to 70°C, Suofu pumps can withstand -120°C to 150°C
➤ Pulsation-Free: Stable flow, ideal for precise metering
04 Applicable Scenarios
The Suofu NP Series urea pump has been successfully applied in the following systems:
Vehicle Exhaust Emission Systems
Gas Engine Exhaust Denitration Ultra-Low Emission Projects
Lime Kiln Low-Temperature Denitration Projects
Emergency Generator Set SCR Systems
05 Usage Recommendations and Precautions
➤ Pre-Pump Filtration: Install a 400-mesh or finer filter to prevent impurities from entering the pump. ➤ Anti-Crystallization Measures: Reverse-rotate to drain the pipeline after shutdown to avoid urea crystallization blockages. ➤ Installation Location: Position the pump as close as possible to the solution tank to enhance self-priming.
➤ Pipe Fixing: Secure pipelines with brackets, ensuring pipe diameter aligns with the pump port to reduce vibration and stress.
Choosing a suitable urea pump is not just about technical compatibility but also a comprehensive consideration of system stability, environmental compliance, and long-term operating costs. Suofu's NP Series Micro Magnetic Gear Pump, with its advantages of leak-free operation, high pressure, strong self-priming, and long service life, has become the preferred pump for many SCR projects.
