Control of Sludge Destruction in Shipboard Incinerators

摘要

The Navy is interested in developing an actively controlled sludge incinerator using pulse combustion technology. This study is aimed at determining the feasibility, developing the technology to construct a suitable pulse combustor, and examining the benefits. Two approaches have been taken towards developing a suitable pulse combustor; the development of a tunable pulse combustor that can force resonant oscillations in the incinerator, and developing a high amplitude pulse combustor to generate non-resonant oscillations. While tunable combustors offer certain advantages, they currently have shortcomings, such as the inability to operate on liquid fuels. Therefore, a fixed-frequency combustor is currently a more practical approach. Tests showed that the pulse combustor exhaust can atomize a stream of liquid, which may allow replacing the currently used two-phase atomizer. Pulsed incineration tests were performed using a gas fired burner that operated at 80Hz, 240Hz, or in steady state mode, allowing comparisons to be drawn between different modes of excitation. Heat losses from the incinerator were greatly increased by pulsations, and the combustor emitted roughly 50% less nitrogen oxides when pulsating. Despite increased heat losses, the evaporative efficiency of the incinerator was typically 50% greater when pulsed. Methanol and sugar solutions were tested as waste surrogates, but low chamber temperatures resulted in unreliable results.