Progress in FGD chimneys
F. Henseler
CICIND REPORT Vol. 12, No. 1, 1996
Order No: CR-014
The paper examines the lessons learned from the failures and successes of various solutions to the problems posed to chimneys by FGD. It briefly describes the flue gas conditions to be found downstream of various FGD systems and examines the implications for the design of the chimneys. The paper then describes various aspects of the design of today's FGD chimneys, embodying the lessons of past experience. These include the concept of "Life cycle cost analysis" - which analyses the total cost, including capital cost, maintenance and operating costs and also demolishing/disposal costs. One result of such analyses is the favouring of liners of titanium or high nickel alloys. Gas flow conditions at the top of the chimney and at the inlet duct entries is examined in some detail, as are the implications for chimney design. The paper closes with an examination of FGD plants without chimneys - i.e. where flue gases are emitted via cooling towers.