Understanding the Difference Between SMF-AR and CRT Systems
Reduce diesel emissions effectively
Understanding the Difference Between SMF-AR and CRT Systems
When it comes to reducing diesel emissions effectively and maintaining engine efficiency, selecting the right Diesel Particulate Filter (DPF) is critical. At HJS Emission Technology South Africa, we specialise in providing advanced DPF solutions tailored for demanding environments such as mining, construction, and industrial applications. In this article, we break down the difference between SMF-AR and CRT systems, helping you identify the most suitable solution for your engine and emissions profile.
What is a CRT (Continuous Regeneration Trap)?
A CRT system is a passive regeneration Diesel Particulate Filter that relies on high exhaust gas temperatures to oxidise soot continuously. This system by HJS is groundbreaking German technology that has been adapted to suit various applications, including light and heavy-duty vehicles used in underground mining.
Key Features:
- Soot Collection: Captures soot particles as exhaust gases pass through the filter.
- Self-Regeneration: At optimal exhaust temperatures, the system burns off soot without any external input.
- Ash Accumulation: The result is fine ash stored in the filter, requiring periodic cleaning or replacement.
Best Suited For: Engines that consistently operate under high loads or long duty cycles, such as highway vehicles or well-ventilated mining equipment, where exhaust temperatures remain elevated.
What is an SMF-AR (Sintered Metal Filter – Active Regeneration)?
The SMF-AR is an advanced DPF system engineered for applications where passive regeneration is not feasible due to lower or fluctuating exhaust gas temperatures.
Key Components:
- Ferrous Additive System: Injects a liquid additive into the fuel system to lower soot combustion temperatures.
- Integrated Heating Element: Initiates active soot burn-off within the filter.
- Electronic Monitoring: Includes additive reservoirs, pumps, filters, and airflow sensors managed via ECU for precise control.
How It Works:
- The additive chemically bonds with soot during combustion.
- Once the system detects backpressure reaching a predefined threshold, the ECU activates the heating element.
- Soot is burned off actively, leaving only fine ash for collection.
Ideal For: Vehicles or machines with variable load conditions or short operating cycles — typical in underground mining, construction, or low-idling fleets.
Understanding the Difference Between SMF-AR and CRT System: A Quick Comparison
Feature | CRT | SMF-AR |
Regeneration Type | Passive – temperature-dependent | Active – uses additive + heating element |
Installation | Close to engine manifold or turbocharger | Flexible – can be installed farther downstream |
Maintenance | Minimal (temperature dependent) | Requires additive refill and additive filter changes |
Best Application | Consistent high-temperature engines | Low-temp, intermittent use, stop-start applications |
Choosing the Right DPF System for Your Engine
Understanding the difference between SMF-AR and CRT Systems is important in deciding on a suitable Diesel Particulate Filter for your application and this decision depends on multiple variables:
- Engine model and duty cycle
- Exhaust temperature and opacity readings
- Installation constraints
- Local environmental regulations
At HJS Emission Technology SA, our team of emission experts offers tailored solutions based on your operational environment and emission control needs.
Need Assistance?
If you’re unsure which Diesel Particulate Filter system best suits your application, contact HJS Emission Technology SA for expert guidance.