The plate catalysts have been specially developed for extreme service conditions. They have the following characteristics:

Catalyst composition

• Stainless steel carrier
• Active catalytic material: TiO₂, V oxide, Mo- or W-oxide

Catalyst properties

• Typical operating temperature range: 280 - 450 °C
• Variable pitch
• Minimal dust deposition
• High erosion resistance
• Low SO₂ conversion rate
• Low pressure drop

Applications

For high-dust flue gas applications and special applications (coal-fired power plants, industrial process plants, oil refinery power plants, etc.)

The honeycomb catalyst has square flow channels and entirely consists of ceramics. It has the following characteristics:

Catalyst composition

• Entirely consisting of active material
• Active catalytic material: TiO₂, V oxide, W oxide

Catalyst properties

• Typical operating temperature range: 170 - 510 °C
• High specific surface area
• Pitch size 2.7 mm to 8.2 mm
• High activity in low-dust flue gases (low volume)
• Pressure drop optimized
• Honeycomb length and number of cells variable

Applications

For low-dust flue gas applications (plants firing high-grade coal, oil or gas; gas turbines, diesel applications etc.)

Besides our 'standard catalysts', operating in a temperature range of approx. 280 to 450 °C, we also offer special types of catalysts for low temperature and high temperature installations.

High-Dust Configuration

In the high-dust configuration, the SCR reactor is installed directly downstream of the economizer and upstream of the air preheater. The main advantage of this arrangement is that preheating of the flue gas is not necessary. The flue gas temperature normally varies between 300 and 430 °C. The principal advantages of the high-dust system are lower capital investment and operating costs.

Low-Dust Configuration

In this arrangement, the catalyst is situated downstream of electrostatic precipitator. The flue gases entering the SCR reactor therefore contain only little dust, but the gases are rich in SO2. The flue gas temperatures are usually sufficient without further treating.

Tail-End Arrangement

This configuration is widely employed in western Europe. It has been used in particular for retrofits of existing power plants. In this arrangement, the SCR unit is placed at the end of the flue gas cleaning equipment [i.e., after the precipitator and the flue gas desulfurization (FGD) unit]. This means that the flue gas contains very little dust, SO2 and catalyst poisons when entering the catalyst. Preheating of the flue gas is necessary influencing installation and operation costs