Advanced in-duct sorbent injection process for SO{sub 2} control

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:254711

Withum, J A; Rosenhoover, W A; Stouffer, M R ^[1]

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1. CONSOL Inc., Library, PA (United States); and others

This paper describes the status of development of an advanced duct-sorbent-injection process for the control of SO{sub 2} emissions from coal-fired power plants. The technical objective of the project is to develop a low-capital-cost process capable of over 90% SO{sub 2} removal as a retrofit option for compliance with the 1990 Clean Air Act Amendments. A complementary objective is to achieve sufficiently high sorbent utilization (60% with hydrated lime) so that levelized costs are lower than wet limestone scrubbing costs over a wide range of coal types and plant sizes. The SO{sub 2} removal and sorbent utilization objectives were achieved. The original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization were exceeded in 0.3 MWe pilot plant operations through a combination of equipment design improvements and sorbent recycle optimization. The 90% SO{sub 2} removal target was achieved at sorbent utilizations of 70-75%. Up to 99% SO{sub 2} removal was attained at 60% sorbent utilization. A simplified equipment design was tested and its operability was confirmed in pilot plant operation. An interim economic evaluation was completed based on these results. Current work also includes the development and testing of improved sorbents. The advanced duct-sorbent-injection process (Advanced Coolside) involves flue gas humidification to the adiabatic saturation point using a contacting device which simultaneously removes fly ash from the flue gas. A sorbent (hydrated lime), injected into the highly humid flue gas downstream of the contactor, captures SO{sub 2} before being removed in the existing particulate collector. The high humidity allows high SO{sub 2} removal. High sorbent utilization is achieved by sorbent recycle. Greater recycle is possible than for previous duct-sorbent-injection processes because the fly ash is removed by the contactor prior to sorbent injection.

• OSTI ID: 254711
• Report Number(s): CONF-940813--
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
ADDITIVES
COST
ECONOMICS
FLUE GAS
FLY ASH
FOSSIL-FUEL POWER PLANTS
HUMIDITY
LIMESTONE
SORBENT INJECTION PROCESSES
SORPTION
SULFUR DIOXIDE