Several players use Fischer-Tropsch Technologies industrially [1,2] or declare to be ready for industrial application [e.g. 3]. Present R&D aims to further increase capacities per train [4] or improve selectivity towards middle distillates [5]. For transforming promising laboratory results into industrial reality, representative performance testing is of particular importance for slurry bubble column FT.
Experimental and Results:
In the Italian refinery of Sannazzaro, a 20 BPD slurry bubble column pilot plant has cumulated more than 20,000 hours time on stream in different campaigns. Non reactive slurry bubble columns corresponding to reactor capacities between 20 BPD and 1000 BPD permitted to determine the profiles for gas hold up and liquid velocities as a function of gas flow, catalyst loading, reactor diameter and internals. A hydrodynamic model based on those data led to design a Large Validation Tool, which can reproduce under reaction conditions a high mechanical stress on the catalyst equivalent to the one experienced in an industrial 15000 BPD reactor.
While those tools have proven to be efficient for developing an industrial scale FT technology [3], they predict today in a representative manner fines formation, hydrodynamic behavior, activity and selectivity of improved catalysts and / or for optimization of operation conditions to increase the capacity per train.
Discussion and Conclusion:
We will compare the here presented approach to others. We have found that it is mandatory to combine chemical stress from the reaction products with mechanical stress as experienced in an industrial slurry bubble column, in order to evaluate in a reliable way performance stability and fines formation. The potential of improvements will be discussed.
The production of liquid fuels from synthesis gas based on metals catalysis was discovered in years 1920's by Franz Fischer and Hans Tropsch. This synthesis was mainly developed in two steps: the first step occurred during the Second War World in Germany to supply military engines in fuel and the second step occurred during the petroleum embargo imposed to the Republic of South Africa due to the Apartheid. In fact, South Africa developed Fischer- Tropsch process to produce liquid fuels and chemicals for the country.
