Filters and indoor venting?

[Daniel Reetz]

Hi all,

I got a job that's going to require me to live in corporate housing for a year. It's a good gig, I don't want to turn it down, but I'll basically be living in a hotel for all intents and purposes.

Is anyone using a filter system to vent indoors? Or otherwise operating in a similar environment (say, in an office building?)

Any advice or thoughts would be much appreciated.

[Joe Pelonio]

I'm not using one myself, but have seen them used at the trade shows and laser distributors offices/showrooms, and have even seen one used for demos in an actual hotel room.

It's amazing how much they will clean up the exhaust, but you still do get some smells from opening the cover after running a job. Last time I looked into it such systems were selling for a minimum of $3,000.

[Shawn Conklin]

I have been looking at them as well and was going to post in a bit on a related but not exact same area. I think the price point is still the same. The epilog rep told me ballpark $3k for one that "will actually work well" as he put it. And from images I have seen some of the units can be as big as the engraver!

this is one that adafruit uses ... not sure about current price but they said $1900

http://www.odorcontroller.com/laser-air.html

http://www.ladyada.net/wiki/laserinfo/equipment


-Shawn

[Hannu Rinne]

From here http://eng.tbh.eu/ (http://eng.tbh.eu/contact.html) you will find some info & products for extraction systems for laser. I'm not sure if there is any dealer in US
for this company, but this site might be worth of looking...

- Hannu

[Randy Digby]

You might search this forum for "scrubber" and review some of the threads. Several of us operate using scrubbers we built. Some vent back inside although I vent outside. I had to install the scrubber because 50% of my laser time is rastering and vectoring laminated plastic and I had to kill the exhaust odor. My unit takes all of the odor out but since I vent outside, I don't use a HEPA filter. Inside venting, IMHO, would require a HEPA filter.

[Hannu Rinne]

Hi Randy,

Does "scrubber" mean something like leading fumes through water or wet
filter ? I have odor problem, because I'm leading fumes through garage
wall - not any smell inside, but outside... and my neighbours are living about 15 meters from me :o

- Hannu

[Randy Digby]

When used in the context of an "air scrubber", the term refers to cleaning unwanted contaminants (odors and/or particles) from the air. Most air scrubbers used with lasers contain a combination of pre-filters, activated charcoal and HEPA filters to rid, clean or "scrub" the air of contaminants.

As I stated, I don't return the air inside so I use a pre-filter and activated charcoal to remove the odor. The pre-filter catches particles that might otherwise plug the charcoal, reducing it's useful life.

[Hannu Rinne]

I apologize my missunderstanding, my English isn't good at all, I'm sorry !

Still, I just started to think that what would be the effect, if I push the
fumes through water tank ( outside garage wall )...? This kind system is
used a long time in electric motors rewinding process, when removing old
windings from the motor ( burn the coils in the oven and lead the fumes through water tank, without any odor outside the oven ).

Just a thought - but it might work...:rolleyes:
- Hannu

[Dan Hintz]

Hannu,

A water scrub will catch some types of odors (like wood), but not nearly enough (plastics are particularly nasty).

[Joe Pelonio]

Isn't that the same principal as a water pipe/hookah? If so, the smoke is still smoke after going through the water, and removes mostly particles. I imagine the smell would still be there, but wouldn't know for sure.

[Hannu Rinne]

Dan & Joe,

You are both right. This mentioned water system is closed inside the oven
and there still remains smell after process. They use some chemical in the
water to decrease the smells ( I don't know what ) and also you have to change the water very often, otherwise the smell of the water will be
terrible... I think that the best way to remove the odor is to use oilburner,
( afterburner ) which burns all smells and particles with more than 850C
air temperature, but this system might be little tricky to carry out if you
live middle of the town :) Also the economic isn't very good if you can't
utilise the warm air from the burner - and the price of the oil; $ 1,4/litre
here in Finland :eek:

So I just have to make somekind simple filter outside and wonder with my
neighbours from where that bad smell is coming...:D

Regards,
- Hannu

[Daniel Reetz]

Isn't that the same principal as a water pipe/hookah? If so, the smoke is still smoke after going through the water, and removes mostly particles. I imagine the smell would still be there, but wouldn't know for sure.

The main problem with water systems is that the acrylic monomers aren't soluble in water, so they typically won't be filtered out.

I, too, have built my own filter system but it doesn't work particularly well. It contains a few screens for the chunkier stuff, then two handmade activated charcoal filters (4 pounds each) and then a large, deep, 12" HEPA filter from a university surplus auction. It definitely cut the smells down, but it wasn't anywhere near good enough to vent to a room.

Shawn, I'm going to try to talk to Adafruit about their filter system. I like the idea of the electrostatic system -- and they have a thing going called "Ask An Engineer" where you can chat with them on the web. Maybe that's the right way to do it?

[Shawn Conklin]

You mean electrocorp has an engineer contact? Adafruit just uses an electrocorp model. But adafruit definitely has an open business model though so if you can get them to respond they will probably tell you their opinions.

they also have a forum for talking about their laser but not very active. here was one post.
http://forums.adafruit.com/viewtopic.php?f=18&t=7211



personally I am trying to find a good inline filter because i want to filter but even with hepa don't want it ending up in my office.

For what its worth found a listing for the model they use with a price
http://www.artistsupplysource.com/product.php?productid=29509


but who knows with pricing, all of these companies seem pretty closed off when it comes to quick pricing. hard to compare stuff at 3am when no one posts prices online !

[Randy Digby]

Daniel, just a couple of thoughts about why your filter may not be removing all of the odor.

First, you may not have ample charcoal thickness for the air to have enough "hang time" for the charcoal to absorb the odors. My scrubber is 12" x 24" and contains about 2.5" to 3" of activated charcoal covering that entire area. Maybe 12 to 16 lbs., estimated.

Second, not knowing how you arranged your components, if you are blowing exhaust air into the filter assembly, any small hole or opening in the fan housing or hoses will vent dirty air into the room. This can be solved by hooking the input of you blower to the outlet of the filter and let the blower pull a vacuum from the laser through the filter. This keeps all dirty air under negative pressure allowing no venting into the room and only cleaned air is under pressure between the blower and your outside (or inside) vent.

My personal safety decision: I will not vent back into occupied spaces unless I can confirm, through approved and tested air sampling, that the air is clean for human intake. I'm old and worked in the plastics industry for 37 years and have breathed some ugly stuff, but my wife and (when they visit us) kids and grandbaby deserve clean air.

[Jim Coffee]

Good morning Daniel...

I've thought a bit about this thread since I first saw it yesterday. Laser odor is one thing. How about the remaining activities that revolve around laser engraving...spray painting, glues, packaging, cutting, receiving, material storage, shipping. What kind of an operation are you going to be relocating to a "hotel room" for a year? This sounds like an interesting challenge.

[Daniel Reetz]

Great question. Honestly, I'm not sure how it's going to work, and if it is going to work at all. It really is an extended stay hotel room -- I'm not even sure if the windows open.

I suppose a filter like the Purex models could be hooked to a fume hood as easily as anything else, but that doesn't make for safe, smart conditions.

As of now, most of my projects are small in scale, and I'm not doing much selling, mostly prototyping and building things for myself. I have been running a small operation making one or two products over the last few months, but that market has dried up completely.

It may end up being impossible, but I want to do my best to make it work. I am willing to spend money to keep access to my laser. Being without the laser is really something I don't want to think about. In a worst case, I guess I would rent another space and use it there.

[Ralph Tesson]

Hi Daniel,
at Quatro Air our most popular laser model fume extractor is the SPH-426, it has a pre-filter for large particulate, a certified HEPA filter and a hefty 40 Lbs. of activated carbon to remove the odors and VOCs. The carbon filter sits in our LaserBlue Gel (imagine really thick and sticky Jello) so that none of the fumes bypass the filter and escape back into the room. We sell this unit at $1940 direct including filters and the required hoses and clamps. These are in use in over 300 mall kiosks nationwide as well as thousands of industrial and hobbyist setups. PM me if you would like more info or check out our website.