What is SCR and how does SCR work?

SCR = Selctive Catalytic Reduction

The SCR method is intended to control the NOx emissions by means of a SELECTIVE CATALYTIC REDUCTION unit. Selective catalytic reduction is the most common method for removal of NOx in the exhaust gas emitted. The SCR method reduces NOx by using a reducing agent (NH3 – ammonia, mostly in form of aqueous urea solution). This is injected in the exhaust gas where it evaporates and turns to NH3 – ammonia. On the SCR catalyst surface the reduction occurs and breaks the NOx to harmless N2 and H2O.

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How do I submit a request for quotation for a H+H SCR project?

Our SCR systems are tailor made and will be designed to fit to your application. Therefore we need some technical data to your project, respectively emission source. Please download the application form here and submit it by mail to info@huhes.de.

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How many people are needed to operate the SCR / DENOx system?

The SCR / DENOx system is working independently, no manpower is needed to operate the system.

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What is the physical size of the system?

The size of the SCR system is related to
-    Fuel quality
-    NOx inlet catalyst
-    Exhaust gas temperature
-    Reduction rate
Please download our SCR specification sheet here, we will gladly design a specific system on this basis and inform you about the dimensions.

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Does the DENOx / SCR system start up automatically?

Yes, in automatic mode the system will recognize the engine start and then automatically starts injection once the catalyst reached its operating temperature.

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Does SCR affect fuel efficiency?

No. If the SCR is sized correctly and backpressure is at the acceptable level, there should be no loss in fuel economy. The HuHES engineered solution ensures proper backpressure and system integration without loss of effectiveness.

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Does the SCR catalyst also reduce formaldehyde?

Yes, up to 20 – 30 %, moreover DOC (oxidation catalyst) can almost completely reduce formaldehyde.

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SCR Technology

Continued Improvements by H+H

1992First Dual Fuel Project, NL, 8 MW Pielstick engine
Turn Key - CHP for the Reichstag (German parliament building)
1997First Military Vessel - HMS Carlskrona, Sweden
MS Visby / MS Thjelvar – Reederi Gotland
Mobile installation on power trucks for
Caterpillar Rental Power (75 units)
2002Macao Power Plant – 230 MW 2 stroke engines, installation of SCR before turbo charger
HSC Gotlandia I + II; MS Birka Paradise; Staten Island Ferry; Silja Europa
2007Training program for operators of SCR systems
Clean Design - optimized urea consumption with different NOx target values outside ECA zones
Clear Maintenance instruction with wear part sets for 2 year operation time
NOx reduction counter - live counter to see kg NOx reduced
ICP - intelligent catalyst protection - prevent catalyst clogging in low load operation (DP mode)
Silencer elements - can be used when catalyst is not needed
2014Datalogger for NOx reporting
Commissioning of 300 SCR systems - 650 engines