Liquefaction continued solvent

Work has also continued on the solvent-refined coal + hydrocracking concept (the NT.SL, or non-integrat-ed, two-stage liquefaction process), and a pilot plant was operated by Amoco, DOE and the Electric Power Research Institute (EPRI) from 1974 to 1992. 

In addition to continuous bench-scale work, CCDC carried out a rather extensive laboratory program involving the use of the microautoclave reactor. The program developed tests to compare the activities of different solvents. These tests quickly evaluated a solvent so that the performance under coal liquefaction conditions could be predicted. The tests are now used at the Wilsonville SRC Pilot Plant as a means of determining when stable operation has been achieved. 

Continuous Bench-Scale Experimentation With encouraging results obtained from microautoclave tests, experimentation emphasis moved to the bench-scale unit Here the concept of adding Light SRC to the recycle solvent on a continuous basis was tested Earlier work (j>) performed on short contact time coal liquefaction showed Indiana V coal to be out-of-solvent balance Also the operability of the continuous bench-scale SRT unit was highly dependent upon the quality of the solvent ... 

Based on the success of the batch autoclave experiments, continuous liquefaction and coprocessing tests using [(NH4)2MoS4l were made. High coal conversions to solvent-soluble and distillate products were observed at 450 C. Typical continuous unit results in both liquefaction and coprocessing modes at 450°C are presented in Table HI. 

In summary, the pressure-filtration technique is a useful and precise analytical tool in performing the solvent classification of certain coal-derived products. The method will not only give meaningful results comparable to continuous, room-temperature Soxhlet extractions but, most importantly, save many hours in the laboratory. We have found it rapid enough to monitor continuous operations. With coal-oil slurry reaction mixtures obtained from high-temperature coal-liquefaction reactions, the solvent classification can be completed in 1 1/2 to 2 hours. 

Research on the Exxon Donor Solvent (EDS) process began at Exxon in 1966 and by 1975 had progressed from investigations using 100 cm batch units to a continuous j-ton/day pilot plant. With the help of external funding, a 250-ton/day pilot plant was designed and constructed. The Exxon Coal Liquefaction Plant (ECLP) at Baytown, Texas began operations in April 1980, and was shut down and dismantled in late 1982. ... 

---