Environmentally Safe, Large Volume Utilization Applications for Gasification Byproducts

Groppo, J.G. ; Rathbone, R.

University Of Kentucky Research Fdtn

关键词: By-Products;    Fuels;    Slags;    Cements;    Waste Product Utilization;   

DOI  :  10.2172/946137
RP-ID  :  None
RP-ID  :  FC26-04NT42203
RP-ID  :  946137

美国|英语

来源: UNT Digital Library

【 摘 要 】

Samples of gasification by-products produced at Polk Station and Eastman Chemical were obtained and characterized. Bulk samples were prepared for utilization studies by screening at the appropriate size fractions where char and vitreous frit distinctly partitioned. Vitreous frit was concentrated in the +20 mesh fraction while char predominated in the -20+100 mesh fraction. The vitreous frit component derived from each gasifier slag source was evaluated for use as a pozzolan and as aggregate. Pozzolan testing required grinding the frit to very fine sizes which required a minimum of 60 kwhr/ton. Grinding studies showed that the energy requirement for grinding the Polk slag were slightly higher than for the Eastman slag. Fine-ground slag from both gasifiers showed pozzoalnic activity in mortar cube testing and met the ASTM C618 strength requirements after only 3 days. Pozzolanic activity was further examined using British Standard 196-5, and results suggest that the Polk slag was more reactive than the Eastman slag. Neither aggregate showed significant potential for undergoing alkali-silica reactions when used as concrete aggregate with ASTM test method 1260. Testing was conducted to evaluate the use of the frit product as a component of cement kiln feed. The clinker produced was comprised primarily of the desirable components Ca{sub 3}SiO{sub 5} and Ca{sub 2}SiO{sub 4} after raw ingredient proportions were adjusted to reduce the amount of free lime present in the clinker. A mobile processing plant was designed to produce 100 tons of carbon from the Eastman slag to conduct evaluations for use as recycle fuel. The processing plant was mounted on a trailer and hauled to the site for use. Two product stockpiles were generated; the frit stockpile contained 5% LOI while the carbon stockpile contained 62% LOI. The products were used to conduct recycle fuel tests. A processing plant was designed to separate the slag produced at Eastman into 3 usable products. The coarse frit has been shown to be suitable for use as clinker feed for producing Portland cement. The intermediate-size product is enriched in carbon (58-62% C) and may be used as recycle fuel either in the gasifier or in a PC boiler. The fines product contains 30-40% C and may also be used as a recycle gasifier fuel, as is presently done at TECO's Polk Station, however, due to gasifier operating requirements for the production of syngas, this is not feasible at Eastman.