How to regain significant pressure drop utilizing offline HRSG impulse cleaning Vince Barreto and Carl Wise opened their presentation on gas-side cleaning of HRSG tube bundles with a review of the traditional alternatives—dry ice and “open detonation”—moving quickly to introduce Thompson’s impulse (pulse detonation) cleaning system. They said the offline application of their proven technology has shown the potential for dramatic improvements in the cleaning of fouled HRSG tube surfaces.
How it works: A cyclic combustion events creates supersonic impulses as illustrated in Fig 2. Injection of fuel and air into an integral mixing chamber followed by ignition and combustion creates a high-energy shock wave that dislodges deposits on the heat-transfer surface.
Barreto and Wise said the highly compressed pressure front is followed by a low-pressure zone: The instantaneous pressure swing produces the cleaning energy. The system is operated at two impulses per second for a total burst of 80 to 120 impulses at each location as the business end of the device traverses the tube bundle on a rail.