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SamRose
10-25-2016, 12:30 PM
We are looking at the option of installing a positive pressure enclosure for part of our bottling line, the depalletizer through the filler. We have concerns about contamination from dust, as many of our beers are flavored with natural fruit juices that are not fermented out, making them very susceptible to infection. Does anyone have experience with an enclosure that would cover depalletizer through filler? We are looking for ideas.

Thanks

rdcpro
10-25-2016, 03:36 PM
We are looking at the option of installing a positive pressure enclosure for part of our bottling line, the depalletizer through the filler. We have concerns about contamination from dust, as many of our beers are flavored with natural fruit juices that are not fermented out, making them very susceptible to infection. Does anyone have experience with an enclosure that would cover depalletizer through filler? We are looking for ideas.



I've done a fair amount of clean-room installation/maintenance in the past, so I have a couple bits of advice:

1. The filters are REALLY expensive, so for the HEPA filter to last, you need to recirculate the air, which means getting the air balance right between supply and return. It might seem easy to build an enclosure and hang a couple clean room filter modules in the ceiling, but I think your filter will clog fairly quickly if it's getting external air. It also takes time to get clean, after you start the system. Most clean rooms I've working in or on ran 24x7. If the area is really small (probably not if you have a depalletizer), you could use something similar to a down draft fume hood...

2. You can find clean room parts and pieces at amazingly good prices online and at auctions, but a piece of advice that was given to me, and I found very valuable is: know exactly where it came from, and what it was used for. If it was used in a hospital or health clinic, you don't want it, no matter how cheap it is.



The way they typically work is the air comes down in a laminar flow (no turbulence) from the ceiling, and is returned via air ducts at the floor with fans to the plenum at the top. You have to balance these, or air will flow into or out of the enclosure. You can live with a slight positive pressure, even with openings in the enclosure. But you can't really eliminate the return air duct, without blinding your HEPA filter too quickly. You typically need a lot of ducts (in fact, it's usual to have 100% coverage in the ceiling, meaning the entire ceiling is air ducts), and you have to figure on what the bottling line itself is going to do to the air flow. Ideally, the air flows straight down, across the floor to the nearest return duct. Equipment in the way of that air flow needs to be figured out.

There are various "classes" of clean room. You can create a class 10,000 or 100,000 clean room fairly easily. Anyone who enters a class 10,000 or better clean room needs to use smocks or lab-coats, hair covers, and possibly shoe covers. You need a changing area, and an air lock if you're going to be really clean (say 1000k or better). The cleanest one I've ever directly worked on was a class 100...it takes about 10 minutes to suit up to go inside. Obviously you're not trying to do this. The subject is fairly complicated, but you can read up on the basics on Wikipedia: https://en.wikipedia.org/wiki/Cleanroom

They are not going to keep microorganisms out of the air, but they will keep particles that may be contaminated with microorganisms out of the air. My opinion is that creating a "real" clean room is probably a waste of time and money, but enclosing your line to class 10K or 100K standards might be fairly easy and not too expensive if you can find used parts. Assembling modular clean rooms from parts is like building a walk-in cooler from parts...do-able, but a lot of work. Mostly what you need is the ceiling module and the wall/return air duct. The ones I've bought came in sections, you build up, across and down, like an upside down U, and place them next to each other as you go. I don't think you'd get good results trying to build the thing from scratch as a DIY project, though. You'd be more likely to move contaminants around than keep them out.

Regards,
Mike Sharp

TGTimm
10-26-2016, 09:20 AM
Unless you have a miraculous bottling line, you'll be opening that hermetic chamber frequently to clear jammed crowner, etc. How long will it take to get the air clean again after you open the enclosure? How much time does it take to get the enclosure open and shut?

Dean of Clean
10-26-2016, 11:32 AM
We are looking at the option of installing a positive pressure enclosure for part of our bottling line, the depalletizer through the filler. We have concerns about contamination from dust, as many of our beers are flavored with natural fruit juices that are not fermented out, making them very susceptible to infection. Does anyone have experience with an enclosure that would cover depalletizer through filler? We are looking for ideas.

Thanks

I have designed many positive air systems for the food and beverage industry. Depending on the regulatory agencies inspecting or monitoring, there are several options available. What I see for your needs is a system that can accommodate your space for equipment, and tolerate several entries a day. You don't need to get too carried away, you are running a "microchip" plant, which is where a lot of clean room technology came from, along with the pharmaceutical industry. I have designed systems for the "bag in the box" type packaging for products such as liquid pasteurized eggs, juice products, and dairy product packaging. I would first figure the cubic feet of air in the room, give it about eight turnovers per hour on air volume, and have your HVAC contact size the air handling system to accomplish this. You install HEPA air filtration, and temperature control componen tsp if needed. Your input air ducts are sized larger than your return air vents, all which are installed in the ceiling panels. We place ribbons in the ceiling panels to verify air movement is flowing out towards doors or conveyor entries in the walls. It is not as complicated for your application as others are making it to seem. If you need help, call 253-670-8434, ask for dean of clean, and maybe I can walk you through it, and provide you with room calculator, and worksheets. Regards, Dean of Clean

rdcpro
10-26-2016, 04:36 PM
Unless you have a miraculous bottling line, you'll be opening that hermetic chamber frequently to clear jammed crowner, etc. How long will it take to get the air clean again after you open the enclosure? How much time does it take to get the enclosure open and shut?

It doesn't need to be sealed that well. A vinyl strip curtain is all you need at that level (class 10k). There needs to be some walls for the return air ducts, but the ends can be open, covered with a stip curtain, and you can have an opening in the wall with a strip curtain in it. You use air locks for much cleaner classifications.

Regards,
Mike Sharp

dick murton
10-27-2016, 01:48 PM
The sterile filling systems I have seen only bother with the filler, not the associated supply side. Reason being that the incoming bottles / cans are not sterile, and have to be rinsed immediately prior to filling. One of the key aspects seems to be hygiene of the filler heads and conveyors from rinser system through to the discharge conveyors taking the sealed packages out of the filler area. I have seen the results of Ozone and something called Anolyte, produced by a German firm Innowatech used for spraying the filling heads on a regular programmed basis, and whenever the filler stops filling, and of the conveyors, and in the case of PET bottles, the caps and screw threads. Made by electrolysis of pure NaCl. The improvement in hygiene is fairly stunning in fruit juices for instance, which are not pasteurised by heat, but chemically (amazingly certain chemicals are permitted) - to the point where in one instance at least, they have removed the chemical pasteurising agent.

Have a look at this site for starters, but they are UK agents for Innowatech. Perhaps there is a US agent.

So I am not saying don't do a pressurised sterile air cell, but there is more to getting really good results than simply a sterile air cabinet.