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Title: Investigation of a sulfur reduction technique for mild gasification char. [Quarterly] technical report, March 1--May 31, 1993

Technical Report ·
DOI:https://doi.org/10.2172/10175536· OSTI ID:10175536
 [1]
  1. Institute of Gas Technology, Chicago, IL (United States)

The objective of this program is to investigate the desulfurization of mild gasification char using H{sub 2}:CH{sub 4} mixtures. Mild gasification of coal produces char, liquids, and gases at 1000{degrees}--1500{degrees}F and near-ambient pressure. Char, comprising 60--70% of the product, can be used to make high-value form coke for steel making and foundries. However, a sulfur content below 1 wt% is desirable, and char from high-sulfur Illinois coals must be upgraded to meet this criterion. Illinois No. 6 chars were treated in a batch fluidized bed with H{sub 2}:CH{sub 4} blends containing 9--24 vol% CH{sub 4} at 1100{degrees}--1600{degrees}F and 50--200 psig. Sulfur removal up to 92.5 wt% were obtainer, and the char desulfurization susceptibility was related to porosity, density, and crystallite size. The relationships among mild gasification parameters, char properties, and char desulfurization susceptibility are being studied. Acid washing of coal to remove Ca and Fe is being explored for its effect on subsequent sulfur removal, and secondary desulfurization of form coke produced from the desulfurized chars is also being studied. Desulfurization tests of entrained and fluidized-bed reactor chars from IBC-105 coal (4.1--4.3 wt% sulfur) were completed. Desulfurization conditions were 1400{degrees}F, 100--200 psig and reactant gas compositions of 15-49 vol% CH{sub 4} in H{sub 2}. Sulfur removal ranged from 28 to 95%, with carbon losses from 5 to 29%. Acid-washing of the coal prior to mild gasification or the char prior to desulfurization increased its susceptibility to desulfurization, with sulfur content reduced to as low as 0.10 wt% dry char. Fluidized-bed chars were easier to desulfurize than entrained chars, and were less affected by acid-washing.

Research Organization:
Illinois Dept. of Energy and Natural Resources, Springfield, IL (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
FC22-92PC92521
OSTI ID:
10175536
Report Number(s):
DOE/PC/92521-T56; ON: DE93019806
Resource Relation:
Other Information: PBD: [1993]
Country of Publication:
United States
Language:
English