The existing hydrocracking pilot plant unit in CERTH was originally designed for hydro-desulfurization (HDS) of petroleum fractions while today it is used for the study of the Fischer-Tropsch wax hydrocracking process. Thus, a major revamp was performed in order to run unattended with wax feeds. The unit modifications were planned and designed in cooperation with an engineering company and included a new pump suitable for wax viscosities, heat tracing of the pump and pipes, modifications to separation system, auxiliary feed system available for emergency plugging operation and a new pumping station for premixing of wax with diluent or sulfiding agent (for catalyst activation).

The unit reactor is of fixed bed type (95.5 cm length x 2.8 cm ID) capable to work at temperatures up to 550°C and pressures up to 150 atm. The hydrogen is introduced in the reactor through an appropriate feed system while the wax feed through a pump. The reactor outlet is cooled by a double pipe cooler and is led to a separator where the gas and liquid parts were separated. Both liquid and gas streams are completely analyzed in CERTH analytical facilities. The pilot plant unit having a full system of alarms and protections (detectors) is fully automated and functions by means of a computer connected with an automatic control system.