Thermo-fluid mechanisms of high-pressure detonation cleaning for deposit removal from boiler heating surfaces

Severe ash fouling and slagging in waste-heat boilers suppress heat transfer, increase cleaning demand, and raise the risk of unplanned outages. Conventional steam soot blowing remains widely used, but it consumes valuable steam and accelerates tube corrosion. This study proposes a novel high-pressure acetylene/oxygen (C 2 H 2 /O 2 ) detonation cleaning technology for steam-free, non-contact removal of sintered deposits from high-temperature boiler heating surfaces. A prototype was tested at initial filling pressures of 0.1, 0.3, and 0.5 MPa, with reactive-flow simulations extended to 1.0 MPa. Results show that detonation velocity remains close to the Chapman-Jouguet value of approximately 2500 m/s, while pressure impulse, residual gas velocity, and cleaning reach increase with initial pressure. Deposit removal is mainly governed by alternating positive- and negative-gauge-pressure loading and thermal-kinetic scrubbing by hot products. An application-oriented assessment based on boiler operating responses indicated a favorable thermal response consistent with improved heat-transfer recovery. Techno-economic estimates further suggest that the recovered heat-transfer performance could improve steam production and provide favorable economic returns. These results indicate the preliminary engineering potential of the proposed technology, while controlled long-term validation remains necessary. Overall, this study clarifies the coupling between transient compressible flow, tube-wall loading, and deposit removal on heat-transfer surfaces, offering a mechanistic interpretation of how pressure-wave attenuation and thermo-fluid loading affect deposit removal, with implications for maintaining heat-transfer performance in waste-heat boilers.