Original situation
The drums of a fabric drum dryer were fed through 2-way control valves, and every drum drained through its own steam trap. Condensate lay in the drums as a film: the drum surface ran cooler away from the steam inlet, and the fabric dried unevenly and more slowly.
Technical enhancement
- Two Jetomat® steam ejectors (Baelz 590, DN 50), driven by live steam, now feed the drums.
- The drum traps came out. Every drum drains untrapped into one flash tank.
- The flash steam is drawn back by the Jetomats and returned to the drums with the motive steam: a closed recirculation loop. Condensate leaves through a single trap.
- Converted in March 2012, on the running dryer.
The result
| Drum dryer | Before | After | Change |
|---|---|---|---|
| Steam per unit of fabric | 0.402 t | 0.341 t | −15.2% |
- 15.2% less steam for the same fabric, measured on the same dryer before and after
- The drums heat evenly over their full length
- One trap instead of one per drum
Why it works
In a trapped drum, condensate collects until the trap opens, and the water film on the shell is a barrier to heat. With recirculation, steam moves through every drum at high velocity, keeps that film thin and sweeps the condensate out, so the full length of each drum heats evenly and the fabric dries faster on less steam. The flash steam that the traps would have released goes back into the drums.
Takeaway
A drum dryer is a row of heat exchangers that traps starve. Two Jetomats and one flash tank turn it into one even, fast-draining loop.