Application of pulse detonation technology for boiler slag removal

Pulse detonation technology for removing slag and fouling deposits in coal-fired utility power plant boilers offers great potential. This technology offers a potentially convenient, inexpensive, yet efficient way for on-line slag removal. This paper presents a feasibility study that includes both Computational Fluid Dynamics (CFD) simulations and laboratory experiments. CFD simulations provided visual and quantitative data to study the potential mechanisms for removal of slag. Mechanisms included direct impact, flow scrubbing, wave reflection and negative velocity impact on the back side of the tubes. Several experiments were carried out to verify the potential of the pulse detonation technology. Experiments were done using a pulse detonation engine and heat exchanger tubes with different types of slag placed in different orientations on the tubes. Tubes were placed at various distances from the detonation tube and in different configurations. The results present a strong case for the application of this technology for online slag removal. It is especially effective for removal of slag on the back sides of the tubes where other traditional methods are not very successful. A preliminary cost analysis indicated that the technology can be paid for within the first year itself and provide substantial savings in the subsequent years.