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View Full Version : Using Hansen Auto Purger without a water bubbler







simplygold
18-05-2014, 07:56 AM
Will the Hansen Auto Purger work properly if the water bubbler is disconnected and the NCG are venting directly into the atmosphere? I know this practice is dangerous and possibly against the law, but I have seen this at a plant I did some work for (vented into a relief stack).

Their reason for not using the water bubbler is that they couldn't go anywhere with the water after the NCG/NH3 was vented. The drain in the motor room carried the water into the plant and caused problems when the production workers smelled the ammonia.

What is the best way to vent NCG with the Hansen AP if the water drain carries the water and smell through a production area or some other place where people can smell it?

Segei
18-05-2014, 03:05 PM
Increase water flow for bubbler and/or reduce air leak into the system.

HVACRsaurus
18-05-2014, 03:25 PM
I have seen some purgers vented to air, brand / style shouldn't matter.

Given the conditions you describe, vent to air it seems worth a try.

RANGER1
18-05-2014, 09:36 PM
simplygold,
As above or relief vent a possibility, but you may still have a smell floating about plant, same as venting to local area of purger.
If changing relief valves you would have to turn it off.
Have seen one plant with a large plastic drum say 200 litres or 44 gallons filled with water.
Purger, if working properly vents mostly air, so change water every so often.
You of course still have the problem of that water, but maybe you could neutralize first.

simplygold
19-05-2014, 07:37 AM
Thank you for your help. On the Hansen website I found the manual which says the water makeup for the purger should be between 30-80psig. The manual said nothing about letting the purger vent to atmosphere.

I just wanted to know if this practice affects the ability of the purger to remove NCG from the system. The plant where the purger was venting into a relief stack was also losing a lot of ammonia through the purger.

RANGER1
19-05-2014, 11:14 AM
Thank you for your help. On the Hansen website I found the manual which says the water makeup for the purger should be between 30-80psig. The manual said nothing about letting the purger vent to atmosphere.

I just wanted to know if this practice affects the ability of the purger to remove NCG from the system. The plant where the purger was venting into a relief stack was also losing a lot of ammonia through the purger.

Whether it drains to air or water makes no difference, as long as it works properly.

Just wondering have you watched its operation & the correct function of all the timers etc as in the manual. it talks about water flush for 30 secs after foul gas purge turns off.

Also check solenoid to bubbler is not leaking causing possible build up of ammonia in it.
Page 12 of the manual states how bubbler works.
IF you have another safer drain point that avoids the factory drain, then it could be piped to that.
It also mentions about bubbler being modified to push drain waste water up approx 3 meters before draining, this May or may not help you if a more suitable drain point is available (page 5).

Tycho
19-05-2014, 09:21 PM
I have no experience with the Hansen Auto Purger, but it looks really complicated in the pictures i found :)

the company I work for use the GEA Grasso self limiting purger, it has a 6mm pipe that vents to atmosphere, I haven't checked the capacity compared to the Hansen Auto purger.

We have been using the GEA purger for 15 years and on all installations it is vented to atmosphere inside the compressor room and I have never smelled or have anyone tell me that the release from the purger set of the gas detectors or caused any residue smell.

There was one site where we attached a plastic hose to the vent line and lead it out to fresh air because the purger was right next to the gas detector *duh* :) but this was in a system placed inside a shipping container with nearly no ventilation.

I've seen a few places where the vent line has been lead down into a soda bottle with water, but when asked the site engineer says it's so he can keep an eye on the bubbles.

I always advise against it, for two reasons, first, it could cause water to travel up the pipe and enter the system, second because the contents of the bottle would be considered hazardous waste according to Norwegian regulations.

I only throw in the hazardous waste part when talking to them because if they get hit by a surprise inspection they would need to work out a procedure for disposing of the 0.5 liter of "hazardous waste" in the soda bottle, so it's more of an "fyi, if the inspector comes, remove the bottle before he gets to the compressor room" :)

RANGER1
19-05-2014, 09:34 PM
I have no experience with the Hansen Auto Purger, but it looks really complicated in the pictures i found :)

the company I work for use the GEA Grasso self limiting purger, it has a 6mm pipe that vents to atmosphere, I haven't checked the capacity compared to the Hansen Auto purger.

We have been using the GEA purger for 15 years and on all installations it is vented to atmosphere inside the compressor room and I have never smelled or have anyone tell me that the release from the purger set of the gas detectors or caused any residue smell.

There was one site where we attached a plastic hose to the vent line and lead it out to fresh air because the purger was right next to the gas detector *duh* :) but this was in a system placed inside a shipping container with nearly no ventilation.

I've seen a few places where the vent line has been lead down into a soda bottle with water, but when asked the site engineer says it's so he can keep an eye on the bubbles.

I always advise against it, for two reasons, first, it could cause water to travel up the pipe and enter the system, second because the contents of the bottle would be considered hazardous waste according to Norwegian regulations.

I only throw in the hazardous waste part when talking to them because if they get hit by a surprise inspection they would need to work out a procedure for disposing of the 0.5 liter of "hazardous waste" in the soda bottle, so it's more of an "fyi, if the inspector comes, remove the bottle before he gets to the compressor room" :)

Tyco, these GEA purgers, are they the ones with a small fridge system in them run on ***** or similar?
http://www.gearefrigeration.com/Product%20Documents/Grasso%20Purger/Brochure_GG%20Purger_English_11-2013.pdf

Are they good for big plants, or do you have to have more than one?

Tycho
19-05-2014, 10:14 PM
Tyco, these GEA purgers, are they the ones with a small fridge system in them run on ***** or similar?
http://www.gearefrigeration.com/Product%20Documents/Grasso%20Purger/Brochure_GG%20Purger_English_11-2013.pdf

Are they good for big plants, or do you have to have more than one?

yes, they are the one with a tiny refrigerator compressor, we run them on all our freezing systems anything with charges between 1 and 5000 kg of ammonia.

I am very happy with them, because you just connect the power and the forget they are there, because they do their jobs.

We only use one pr system, and even with 4 howden WRV204 compressors running 24/7 at -0.4 bar suction pressure this thing does it's job.

it's like a fire and forget system as long as you install the correctly :)

RANGER1
20-05-2014, 10:40 AM
yes, they are the one with a tiny refrigerator compressor, we run them on all our freezing systems anything with charges between 1 and 5000 kg of ammonia.

I am very happy with them, because you just connect the power and the forget they are there, because they do their jobs.

We only use one pr system, and even with 4 howden WRV204 compressors running 24/7 at -0.4 bar suction pressure this thing does it's job.

it's like a fire and forget system as long as you install the correctly :)

Tyco have only seen a few, I think they are a bit pricey, not that Hansen or Parker are cheap.
We mainly use Hansen type due to their multi point operation on larger plants.
They continually cycle around condenser drains & liquid receiver.
They also have a counter for number of purges, so you know something is wrong if number of purges
increases out of the norm.
Armstrong was the previous most popular.
I also thought there was some replaceable tip on Grasso which has to be replaced every so often?