Frequently asked questions

It is combustion, not an explosion. A small charge of propane mixed with compressed air is ignited inside a sturdy, pressure-resistant process chamber outside the boiler. The pressure wave is created when the piston opens and the gas is released into the boiler through a nozzle. There is no expansion directly inside the boiler, so the cleaning is contact-free and far gentler than mechanical methods.

Combustion pressure is typically set between 150 and 600 bar. The generator is designed and certified for 900 bar. Higher pressures (up to ~750 bar) are used on large coal power plants; 600 bar is the highest practical level for waste-to-energy boilers. Operators can adjust both the trigger pressure and the firing frequency online.

Only about 1.2 m of clearance from the boiler membrane wall. For boilers up to 12 m wide, installation on one side only is sufficient. The generators mount on existing boiler access doors such as manholes, which makes retrofitting straightforward in most configurations — open radiation and convection passes, in vertical or horizontal arrangements.

Yes — it works even on small boilers (e.g. 2.8 m wide). The only requirement is a front distance of at least 1 m between the generator and the tubes or water walls to avoid damaging equipment. On smaller boilers the generator simply runs at lower pressure (less propane and compressed air per shot).

It depends on the geometry, but as a rule of thumb effective cleaning reaches up to 12 m in the straight (open) direction, up to 6 m above/below, and up to 1 m laterally into tube bundles.

For prevention, the best strategy is frequent, low-pressure blasts — typically one blast per hour at low pressure, which is gentle on the boiler and preserves component life. To clean a boiler that is already fouled, a short series of 2–3 high-pressure blasts works well, though high-pressure blasts put more mechanical stress on the boiler. Commissioning usually starts at low pressure and increases only if needed, always within the boiler's design limits.

We guarantee noise levels not exceeding 120 dBA; ear protection is required near the equipment during a blast, and an acoustic and visual signal warns operators beforehand. On flue-gas pressure, we have seen no measurable effect on boilers with a flue-gas flow above ~80,000 Nm³/h — a single shot injects only about 3 Nm³ of gas.

Both ignite a gas/compressed-air mixture outside the boiler, but the P-Wave Generator uses propane (about three times the heat value of natural gas, so less gas and smaller pipework) and needs no nitrogen. Its cast, one-piece process chamber runs at up to 600 bar (certified 900 bar) versus ~280 bar for the flanged SPG design — so the P-Wave Generator delivers much higher power. It also weighs less (~250 kg), reducing the load on the boiler, and lets operators tune intensity and firing sequence continuously, online.

The fuel gas should contain more than 90% propane. The remaining components should come from: propylene, ethane, ethylene, isobutane or n-butane. Combustion produces mainly carbon dioxide and water vapour.