The Central Heating Plant at Cornell University provides steam to Campus. The plant includes two coal-fired boilers each of which control particulate emissions with a fabric filter. The plant became subject to new emission limits under 40 CFR Part 63, Subpart DDDDD, also known as the Industrial Boiler MACT rule. The rule requires that the coal fired boilers at the plant meet a mercury emission limit. Through testing and a feasibility study, Cornell determined that sorbent injection ahead of the baghouse on each boiler would be required to achieve compliance. Therefore, in January of 2007, Cornell began a full-scale sorbent injection test program on one of the boilers. The goal of the test program was to determine the optimum sorbent(s), injection rate, and process conditions upon which to base the design of the final sorbent injection system to be installed on each boiler. The vast majority of full-scale sorbent injection testing conducted over the last few years has been on electric utility coal-fired boilers in which the flue gas temperature is generally less than 325 ℉. Furthermore, the vast majority of these tests have been conducted on units in which the particulate control device is an ESP. Relatively few tests have been conducted on baghouses because of the relatively good mercury control observed with sorbent injection and relatively low flue gas temperature. However, the Cornell boiler presents a unique challenge in that the flue gas temperature entering the baghouse is typically near 375 ℉, which makes mercury
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