Ikelic - Alliance Digital Repository

PROJECT ACTIVITIES
POINT OF AYR LIQUEFACTION PLANT
BEGINNING TENTH RUN
British Coal's 2.5-ton per day Liquid Solvent Ex
traction pilot plant at Point of Ayr, North Wales,
United Kingdom has completed nine runs, with
up to 2,000 hours of operating time available for
each run. Run 10, scheduled for 3,000 hours,
was to start in January 1995. H. Williams and
R. Hughes of British Coal gave the pilot plant
results to the 11th Annual Pittsburgh Coal Con
ference last fall. A companion paper by
S. Walton and M. Pudifoot gave some findings
regarding the importance of good coal feed
analysis, because they found that segregation
could occur in the feedhopper.
During the nine runs made to date, there have
been some equipment-related problems, but
these have been overcome as the runs have
progressed. The main problem areas have been
compressors, ebullating pumps and magnetic
drive pumps. Liquid yields of above 60 percent
based on the dry ash free coal feed have been
achieved.
The process involves feeding pulverized coal
which is first slurried with solvent to a digester
where up to 95 percent of the coal is dissolved.
Filtration is used to remove solids (mineral matter
and undissolved coal) and the valuable "coal ex
solution"
tract enters the ebullating bed
hydrocracking reactors. Here, catalytic reactions
carried out at 200 bar and 400-450C change the
structure of the coal by introducing hydrogen.
Final distillation recovers the solvent for recycling
and yields three main products:
- LPG
- Middle
(propane and butane)
Naphtha
distillate
The naphtha and middle distillate are subse
quently upgraded, using conventional oil industry
techniques, to gasoline and diesel.
COAL
4-1
Exxon Joins Project
Early
in 1994 it was announced that Exxon
Research and Engineering had joined the Point
of Ayr project. Exxon is the second oil company
(in addition to Amoco) to participate in the
project. Exxon will invest 630,000 pounds in the
project. This should lend considerable weight to
the successful development of the process. The
agreement gives Exxon the right to increase their
participation in the future and to license the tech
nology.
####
ENCOAL PLANT ENTERS PRODUCTION
STAGE
Last June, SGI International reported that the
ENCOAL Clean Coal demonstration plant located
next to Triton Coal Company's Buckskin Mine
near Gillette, Wyoming, is in production. The
plant uses the LFC (Liquids From Coal) Process
Technology developed by SGI.
The plant, which completed a 24-month
demonstration and test phase, now processes
500 tons of coal per day from the Powder River
Basin of Wyoming. The low-sulfur, low-moisture,
high-BTU clean coal product is being success
fully produced and stockpiled for shipment to
utilities for test burns. The low-sulfur coal oil also
produced by the plant has been shipped and suc
cessfully used by industrial customers.
ENCOAL Corporation owns the plant and
licenses the LFC Process from the TEK-KOL
Partnership, jointly owned by SMC Mining Com
pany and SGI International. ENCOAL is a sub
sidiary of SMC Mining Company, which is owned
by Zeigler Coal Holding Company, a major U.S.
coal producer.
While coal mined from Wyoming's Powder River
Basin has some of the naturally lowest levels of
sulfur available, it is relatively high in moisture,
increasing transportation costs while decreasing
its energy value.
THE SYNTHETIC FUELS REPORT, JANUARY 1995