Complete SCR
(DeNOx) Systems

Exhaust Cleaning Systems for stationary
combustion engines, non-engine
combustion processes and industrial boilers.

H+H SCR Technology for lower NOx emissions
H+H SCR Technology for lower NOx emissions

Environmentally-friendly, efficient, long-lasting


Engine and non-engine combustion processes in stationary and industrial applications are subject to strict legal guidelines, just as
44. BImSchV (Regulation on medium combustion plants, gas turbines and combustion engines plants) and DIRECTIVE (EU) 2015/2193
(on the limitation of emissions of certain pollutants into the air from medium combustion plants), demanding the implementation of efficient
measures to reduce emissions while maintaining the best possible levels of performance. A challenge that H+H successfully masters with
its plant technology. Our exhaust gas treatment plants enable the achievement of nitrogen oxide reduction rates > 95 %. Engines
operated in this manner undershoot pertinent limits to a considerable degree.

» Overview of current emission limits and laws in Europe

  • More than 30 years of experience

    Consulting and Planning

    » Learn more
  • 100% made in Germany

    High-Quality Components

    » Learn more
  • Design & Manufacturing

    Know-How and Service

    » Learn more
  • Sustainability and Reliability

    Continuous improvement process

    » Learn more


More than 30 years of experience

Consulting and Planning

Benefit from more than 30 years of experience with DENOx plant engineering.  Our team is very pleased to support you with the planning of your exhaust treatment system and designs a tailor-made concept according to your application. The modular design of our SCR systems facilitates installation, only a minimum of cables and pipelines are required.

H+H also provides the exactly dimensioned accessory components such as,
for example, reducing agent tanks, compressed air stations or exhaust gas analyzers.

Your system also needs an oxidation catalyst? This may be necessary to convert
for example formaldehyde or other hydrocarbons as well as carbon monoxide.
An oxidation catalyst can simply be added to the housing of the SCR catalyst
or can be installed separately. We would be pleased to advise you about any possibilities.


100% made in Germany

High-Quality Components for rough
conditions and for a long life time

The use of the proven industry components, such as the equipment with robust sensors, guarantees a long life time and reliable system performance. This ensures a long-term supply of spare parts. This measure allows operation with low but sophisticated and preventive maintenance. 

Our service team will be at your disposal at any time with advice and assistance. 


Design & Manufacturing

Know-How and Service

SCR systems of H+H are programmed and further developed by our team. Due to the know-how in programming, the diversity in the various areas of exhaust treatment system is almost infinite. Different reducing agents, different load curves or fuels, communication with the power station control room – all technologies and requests can be considered and implemented here. 

Should you require a reporting or recording of the performance data, our specially developed software CaReCon (Catalyst Remote Control) can be of assistance. This feature allows us also to provide remote maintenance access in order to carry out software updates or to support you in case of interruptions. And all this without any waiting times or expensive travel costs!



Sustainability and Reliability

Continuous improvement process

Our experience, gained with more than 1000 SCR systems from over 30 years, will be integrated in every new project. In addition, a continuous improvement process made with the development of our service activities will also be implemented. 

We would like to win you as our customer and to achieve your satisfaction. If you place an order for the second exhaust treatment system at H+H, then we will also be satisfied.

You can see a graphic overview of the possible areas of application for stationary SCR systems, for example a greenhouse, a gas turbine, an emergency power data center.

It is all about the optimal temperature 

Operating Temperatures

Our H+H SCR systems are suitable for operating temperatures
between 180 and 540°C. The catalyst must be operated at a minimum
temperature, however the maximum must not be exceeded. The
minimum temperature is a design criteria and an important parameter
for the NOx conversion. The lower the temperature, the more catalyst
is needed.

The operating temperature for combustion engines (MGO / MDO)
is at least 290-310°C up to a maximum of 540°C.

With non-engine combustion processes (biomass, glass furnace,
SNCR + SCR) as well as for industrial boilers the H+H SCR systems
require at least a temperature of 180°C up to a maximum of 540°C.

No matter if CHP, waste incineration plant, processes of the chemical
industry, Biogas, power plant, backup engine (e.g. for data centers)
etc., your individual SCR reactor, static mixer, urea injection
system and everything else needed to operate this exhaust
gas aftertreatment system is designed according to
your boundary conditions.

Global references speak for themselves

Our References

  • Industry

    Combustion Processes

    RTO in cooperation with Krantz  

    Exhaust Mass Flow Rate:

    6.000 Nm³/h
    Emission Source: RTO Exhaust
    NOx out of catalyst: 80 mg/Nm³

  • Industry

    Gas Turbine

    Spectra Energy Danville Compressor Station in cooperation with AeriNOx  

    Engine Producer:

    General Electric
    Type: GE FRAME 3
    Power: 44 MW
    Fuel: Natural Gas
    NOx Reduction: 100 -> 25 ppm

  • Industry

    Combustion Engine

    Modernization CHP-Kapaunenstraße in cooperation with EAN  

    Engine Producer:

    Type: J616
    Power: 2x 2679 kW
    Fuel: Natural Gas
    NOx Reduction: > 80%