SCR-Smartline for use in biogas systems

Fischer Abgastechnik is the go-to specialist for exhaust aftertreatment systems. The company – which is based in Emsdetten (Germany) and has an in-house development and design department for open and closed-loop controls and CFD calculations – has just developed and launched a more cost-effective SCR system in the form of its modular SCR-Smartline system. This product complements the company’s already well-established SCR-HD (heavy duty) and SCR-Industry systems. Proprietary open and closed-loop control units are combined with validated components from the automotive sector to produce a perfectly rounded, all-in-one system. Its modular concept sets it apart, and the system can be used on its own to dispense aqueous urea solution at a rate of up to 10 kg/h. When combined with the Fischer BOC catalysts, which were introduced over 10 years ago, it can reliably ensure complete compliance with all limits values of the 44th Ordinance for the Implementation of the German Federal Immission Control Act (BISchV). The Fischer engineers are specialists in bespoke and retrofit solutions.


The dosing system

The SCR dosing system is a component of any SCR system or plant (see above) and cannot function on its own. It performs the following tasks:

  • Uptake of the reducing agent from the tank or the day tank
  • Precise dosing of the required volume of reducing agent in each case
  • Delivery of the dosed reducing agent to the two-fluid nozzle, which is mounted in the exhaust pipe at the beginning of the mixing section upstream of the SCR reactor
  • Introduction of compressed air to atomise the reducing agent in the exhaust gas

Structure of an SCR-Smartline dosing system
The SCR-Smartline dosing system has the following main components:

  • Unit dosage system (UDS) with dosing pump, flush valve or air control valve, pressure sensor for compressed air, pressure and temperature sensor for the reducing agent
  • Compressed air supply 
  • Two-fluid nozzle 
  • Control unit with data logger and display, optionally available with remote maintenance module, optionally available with back pressure monitoring and exhaust gas bypass control
  • Exhaust gas temperature sensors before and after the catalytic converter; also available as options: NOx before and after the catalytic converter and exhaust backpressure 
  • Reducing agent tank (optional)