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Das PRENFLO® Flugstromverfahren mit Direct Quench (entrained-flow process with direct quench (PDQ).

"Der PRENFLO® (PRessurized ENtrained FLOw) Direct Quench (PDQ)-Prozess kombiniert das technologisch avancierte Trockenzufuhrsystem, die Vielzahl von Brennern und die Membranwand des PRENFLO® PSG-Prozesses mit einem geschützten Wassereindüsungssystem (Water Quench), das das rohe Syngas für die nachfolgende Gasbehandlung mit Wasser sättigt.

Kapitalintensive Systeme, wie z.B. das Abhitzekesselsystem, das trockene Flugascheaustragungssystem und der Quench-Gaskompressor werden daher nicht mehr benötigt.

Preferred applications

NPUT: feedstocks with low ash content or low ash softening point.

OUTPUT: hydrogen-rich syngas for chemical applications, such as ammonia, methanol, synthetic fuels, or electrical power with carbon capture and storage/utilization (CCS/CCU).

Main process data

up to 1,200 MWth single train capacity

1. Cyclone filter

2. Lock hopper

3. Feed bin


5. Direct quench

6. Slag crusher/collector (if required)

7. Slag lock hopper

8. Steam drum

9. Slurry filtration

10. Scrubber

Main process features

  • Entrained-flow
  • Dry dust feed for high efficiency
  • Multiple burners with high availability and long lifetime
  • Horizontally arranged burners for high carbon conversion
  • Membrane wall with long lifetime
  • Full water quench for syngas saturation
  • Shorter supply and construction schedule
  • Lower investment cost
  • Operates above ash melting point

Process description

First, the feed dust is prepared in the feed preparation unit. Approximately 80% of the dust is smaller than 0.1 mm. This feed dust is then gasified in the PRENFLO® gasifier using oxygen and steam as the gasification agent. The gasification temperature is higher than the ash melting temperature, which allows the coal ash to be removed as slag. The cooled-type gasifier is equipped with multiple, horizontally arranged burners.

The raw gas produced, which contains mainly carbon monoxide and hydrogen, is quenched with water in the gasifier / direct quench and then cleaned in a scrubber.

The filter cake from the slurry filtration system is mainly recycled to the gasifier via the feed preparation unit.

The slag from the gasifier can be used as a construction material.

Process flow diagram

Process history

The PRENFLO® PDQ process is an optimized design of the proven PRENFLO® PSG process for the production of chemicals where partial or complete CO-shift of the generated syngas is required.

The gasification chamber, the membrane wall and the burner setup is identical to the PSG version, the only modification is the replacement of the cost -intensive heat recovery sections by a full-water quench system.

A pilot plant - already based on the next PDQ generation - is currently under construction in Dunkirk, France, and will be commissioned in 2017.

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