Scaleup tests and supporting research for the development of duct injection technology: Topical report No. 3, Task 3. 2: Scale-up testing; Topical report No. 4, Task 3. 3: Advanced configurations; Topical report No. 5, Task 3. 4: Process controls; Topical report No. 6, Task 3. 5: Failure modes; Task 3. 6: Waste characterization, Duct Injection Test Facility, Muskingum River Power

Abstract

This document is the third interim report on tests that were conducted at the Duct Injection Test Facility (DITF) operated for the Department of Energy at Unit 5 of the Ohio Power Company's Muskingum River station in Beverly, Ohio. At the DITF dry calcium hydroxide (Ca(OH)2), an aqueous slurry of Ca(OH)[sub 2] (prepared by slaking quicklime), or a mixture of one of these sorbents with waste ash from earlier tests was injected into a slipstream of flue gas from the Unit 5 boiler to achieve partial removal of SO[sub 2] in the flue gas. Up to 50,000 acfm of flue gas was taken from the inlet to the Unit 5 electrostatic precipitator (ESP) for these tests. Water was injected separately with the dry sorbent or as part of the slurry to cool the flue gas and increase the water vapor content of the flue gas. The addition of water, either as a separate spray or in the slurry makes the reaction between the sorbent and the SO[sub 2] more complete; the presumption is that water is effective in the liquid state when it can physically wet the sorbent particles, and not especially effective in the vapor state. Higher values ofmore » calcium utilization were obtained with slurry injection than with dry sorbent injection and humidification. Slurries made from reagent slaked lime, mixtures of reagent slaked lime and recycle ash, and from recycle ash alone were injected through the same nozzles used for humidification. The focus of most of these tests was on the constant addition of recycle ash to reduce the amount of slaked lime required for SO[sub 2] removal (for best economics). Testing was continued until the amount of Ca(OH)[sub 2] in the recycle ash equaled that predicted for equilibrium Two test cases were evaluated: a low Ca/S ratio (1.0 reagent, 44[degrees]/F approach) for 50% SO[sub 2] removal and a high Ca/S ratio (1.7 reagent, 24[degrees]F approach) for 88% SO[sub 2] removal.« less