The case of the disappearing water treatment chemicals, this Friday's case

RayWohlfarth

While doing the boiler maintenance at a brewery, the maintenance tech asked why his water treatment chemical usage would have risen substantially. He also said the oxygen scavenger level in the boiler was always low. The oxygen scavenger is part of the chemical water treatment. The feed adjustments for the pump are the same as the day they set up. Two other clues: the brewing process seems to take longer than it did when the system was new and the low water cutoff is tripping more often.

What would cause this? As usual, I will answer this on Friday at 6am EST

ethicalpaul

Wild guess: The wye filter is dirty/restricted. The boiler calls for makeup water, diluting the oxygen scavenger in it. But I am too ignorant to even guess why his treatment usage would have risen. Except maybe the treatment pump was wired up to activate when the LWCO called for water.

But it would seem they would have noticed the condensate tank overfilling...but maybe it had an overfill drain that wasn't easy to monitor.

It took longer to brew because the boiler was having to heat up a lot more cold water than it should have had to.

Very nice drawing by the way

JUGHNE

Hole in boiler, losing steam up chimney, auto feeder for make up water, in boiler feeder pump tank, activated which activates chem pump.

More fresh cold water, slower steam, ....more chemicals with each water addition.

mattmia2

Boiler leaking above the water line was my thought as well.

ethicalpaul

JUGHNE said:

Hole in boiler, losing steam up chimney, auto feeder for make up water, in boiler feeder pump tank, activated which activates chem pump.

More fresh cold water, slower steam, ....more chemicals with each water addition.

But the chemical levels in the boiler were reported as low...

mattmia2

ethicalpaul said:

JUGHNE said:

Hole in boiler, losing steam up chimney, auto feeder for make up water, in boiler feeder pump tank, activated which activates chem pump.

More fresh cold water, slower steam, ....more chemicals with each water addition.

But the chemical levels in the boiler were reported as low...

The oxygen combines with the scavenger and reduces the level. My guess is the test tests for the active scavenger, not the combined scavenger and oxygen.

ethicalpaul

Thanks! What a cool topic!!

https://www.watertechnologies.com/products/boiler-water/steam-condensate-treatment

NYLamb

My guess: steam trap failed shut so boiler is running strictly on makeup (which may be tied in with chemical pump). Constant makeup would lead to less efficient brewing due to lack of preheated water. As for boiler tripping on low water, guessing a clog in the FW pump strainer. 

Look forward to answer! This was fun..

RayWohlfarth

@mattmia2 You got it right. The customer had removed the vacuum breaker on the kettle and when the steam condensed, it pulled the piping into a vacuum. When the valve for the kettle opened, the steam zoomed out of the boiler at a high velocity taking water with it. The air in the system consumed the oxygen scavenger so the maintenance tech would add more chemical treatment. The other parts of the treatment would not be consumed as quickly and appear as solids in the water. The high solids caused bouncing water and made the carryover worse.

https://youtube.com/watch?v=tok7cZytYTs

RayWohlfarth

here is a drawing of the system Thanks @ethicalpaul