The BioTfuel project partners—Total, IFP, the French Atomic Energy Board, and Sofiproteol—selected the PRENFLO process on the basis of its flexibility in processing a wide variety of biomasses and other resources. It allows high energy efficiency and enables very pure synthesis gas to be produced. A torrefaction pre-treatment plant, which facilitates the application of biomass in the PRENFLO-PDQ entrained-flow gasifier, and ensures lowest possible energy consumption, is installed to allow the use of a wide range of biomasses.

The PRENFLO Direct Quench (PDQ) process is an optimized design of Uhde’s PRENFLO PSG gasification process (steam generation) for chemical applications (e.g. ammonia, methanol, hydrogen, synthetic fuel) and IGCC plants with Carbon Capture and Storage (CCS), where hydrogen-rich syngases are required. It combines the technologically advanced dry feed system, multiple burners and membrane wall of the PRENFLO PSG process with a proprietary water quench system which saturates the raw syngas with water for subsequent gas treatment.

Capital-intensive systems, such as the waste heat boiler system, the dry fly ash removal system and the quench gas compressor, are therefore no longer required.

The PRENFLO PDQ gasifier operates at pressures of 40 bar (4 MPa, 580 psi) and higher and at temperatures above 2,000 °C. Gas temperature at the outlet of the gasifier/quench is 200-250 °C. Carbon conversion is greater than 99%, and typical composition of the raw syngas is more than 85 vol.% CO + H₂, 6-8 vol.% CO₂ and less than 0.1 vol.% CH₄.

The PRENFLO PDQ process was selected for its suitability in processing a variety of feedstocks and in generating hydrogen-rich synthesis gases, such as for Fischer-Tropsch synthesis applications, by which diesel and kerosene can be produced.

The PRENFLO process is currently being used successfully in Puertollano, Spain where the world’s largest combined cycle power station with integrated coal gasification is in operation using petrol coke, coal and biomass as charge materials. Uhde’s PRENFLO process is based on the Koppers-Totzek coal gasification process which was developed around 70 years ago.

The overall budget for the BioTfueL project is €112.7 million (US$151 million). The project includes the construction and operation of two pilot plants in France to produce biodiesel and biokerosene based on biomass gasification using Uhde’s PRENFLO-PDQ process. The plants are scheduled to go into operation in 2012.

BioTfueL’s objective is to remove all existing technological hurdles so that all process steps can be adapted for use in the combined application of biomass and fossil resources, and allow a secure transition to industrial-scale operations.

Throughout the process, BioTfueL will use life cycle analyses to assess the optimum equilibrium between technical-economic performance objectives (investment, yield, flexibility) and environmental demands (energy consumption, CO₂ emissions), and to assist in supporting technological decisions. At the end of the BioTfueL project the partners expect there to be a good market for a significant number of industrial applications.

BioTfueL forms an integral part of the measures taken to implement the EU Directive on renewable energy which stipulates that all fuels should comprise 10% renewable energy by the year 2020.