Direct liquefaction Proof-of-Concept Program, Hydrocarbon Technologies, Inc., Lawrenceville, New Jersey. Final topical report, Bench Run 02 (227-91)

Abstract

This report presents the results of Bench Run PB-02, conducted under the DOE Proof of Concept - Bench Option Program in direct coal liquefaction at Hydrocarbon Technologies, Inc. in Lawrenceville, New Jersey. Bench Run PB-02 was the second of the nine runs planned in the POC Bench Option Contract between the U.S. DOE and Hydrocarbon Technologies, Inc. The primary goal of this bench run was to evaluate the hybrid catalyst system, consisting of a dispersed slurry catalyst in one of the hydroconversion reactors and conventional supported extrudate catalyst in the other hydroconversion reactor, in a high-low two-stage temperature sequence, similar to the one operated at Wilsonville. This hybrid mode of operation with the high-low temperature sequence was studied during direct liquefaction of coal and in coprocessing of coal with Hondo resid and/or waste plastics under high space velocity operating conditions. Another important objective of Bench Run PB-02 was to investigate the novel {open_quotes}interstage internal recycle{close_quotes} of the second stage reactor slurry back to the first stage reactor. Other features of PB-02 included the use of an interstage separator and an in-line fixed bed hydrotreater. In general, it was found during Bench Run PB-02 that the {open_quote}hybrid type{close_quote} catalyst system was not effective for obtaining high levels of process performance as the {open_quote}all dispersed{close_quote} catalyst system, tested earlier, especially at high coal space velocities. The interstage internal recycle of second stage reactor slurry to the first stage reactor feed line was found to improve cracking of liquefaction products. The addition of small amounts of mixed plastics was found to improve the hydrogen utilization in both coal conversion and heavy oil hydrocracking reactions, i.e., plastics resulted in improving the overall distillate yield while at the same time reducing the light gas make and chemical hydrogen consumption.