Pyroflex VFE

Direct firing system 850 to 8000 kW

The very dry, dust-like fuel is blown into the fully ceramic-lined and heavily insulated combustion chamber through one or more blowing lines. The combustion chamber geometry is specially designed for the blowing in of fuel to ensure optimally complete combustion of the fuel as well as the required turbu­lence and flow condi­tions.

Direct firing system VFE

The specialist for the wood industry


Fuels:
Very dry, dust-like fuels from indus­trial wood processing

Direct firing system with high tempe­rature residue combustion for energy production from dust-like wood scrap from wood processing.

Direct firing system

The fuel is blown in according to the injector principle. In other words, no fuel enters the blower fan, avoiding fan wear. The heat storage in the ceramic lining ensures corre­spon­dingly high combustion chamber tempe­ra­tures for very low emissions values. The horizontal 3-pass flame tube-flue tube boiler is installed on top of the combustion chamber as a warm or hot water boiler. Steam boilers or thermal oil boilers can also be supplied, if needed.

Designed for the wood industry

The Pyroflex VFE was specially designed for indus­trial wood processing. Even fuels like MDF or chipboard scraps pose no problem for this firing system.

The low-NOx combustion chamber is designed with primary-side measures such as air staging to reduce NOx emissions. Regulation of the primary air supply together with flue gas recir­cu­lation ensures substoi­chio­metric combustion in the reduction zone.

Secondary air is injected after the reduction zone of the combustion chamber. The corre­sponding firebox geometry combined with the combustion air injection ensures high turbu­lence and mixing with the flue gas, resulting in optimal oxidation (CO burnout) of the combustion gases.

Flue gas recir­cu­lation

The flue gas is drawn into the exhaust line and reintro­duced to the combustion chambers with a fan. This decreases the flame tempe­rature and reduces nitrous oxides. The efficiency of the system is increased as a result since a lower residual oxygen content remains in the flue gas, even in the case of dry fuels.

Equipment and access­ories

Measu­re­ments in the primary air and recir­cu­lation air

The flow rates of the primary and recir­cu­lation air are measured, and the required air quantities are calcu­lated in advance. This achieves optimal combustion results and emissions values in all load stages, including with difficult fuels.

Use of high-quality O2 probes

The secondary air flow rate is regulated based on the detected oxygen level. High-quality O2 probes make it possible to maintain a conti­nuously low residual oxygen level in the flue gas (approx. 5–6% O2 (damp) – depending on the fuel). This allows the highest levels of efficiency to be achieved even in modulating partial load operation.

Ash removal

Due to the in-flight combustion, very little ash remains in the combustion chamber. Ash can be removed from the combustion chamber either manually or automa­ti­cally using a water-cooled screw.