DE Filtration

[mikej_88]

Hey all,
I have a DE filtration question for some of you with experience. When you guys are adding the DE to the tank with the agitator in it, what liquid do you add to mix with the DE? Thanks
MJ

[mlabbe]

I have always allowed the reservoir to backfill with the beer that I am filtering. After sanitizing the filter, purge it with CO2, then backfill with unfiltered beer. It eliminates the problem of dissolved oxygen being added to the beer! Just make sure that you don't start recircing the filter full of unfiltered beer until after you have the slurry prepared. I always backfill the entire filter with beer, prepare the precoat slurry in the reservoir, then start circulating the filter. This distributes the initial yeast load throughout the precoat layer. By the time you have finished the precoat, the filter will be filled with bright beer, and you are ready to roll.

It has worked well for me for many years.

Cheers,
Mike

[gitchegumee]

The experts all say to precoat with filtered beer or deaerated water only, but I use unfiltered beer brought into the filter only after purging the filter with CO2.

[mikej_88]

Ok, thanks guys. So just to make sure, when mixing the DE slurry in the reservoir you guys mix the DE either with unfiltered beer or deaerated water, right? Thats what I thought but last week I was visiting a brewery and the filtering guy walked over to a tub marked sanitizer (a water chlorine mix) and made the DE slurry with that. Now maybe the tank was just mislabled or something but didnt have a chance to talk to the guy about it. I dont have much experience with DE filtering, and was just wondering what you guys had to say about that. As always thanks for your imput
Michael

[J.hammell]

I have also used de-aerated water, that was previously boiled / carbonated then stored in a cold cellar tank.
But i have never used unfilterred beer, does it work better?

[gitchegumee]

To the contrary, I believe unfiltered beer makes for worse precoats. But I have a big filter and a small batch size, so I run full tilt. At this brewery, I never blind the filter even with a massive plug of yeast. With a better matched filter, I would be using either filtered beer, or deaerated water--NEVER a chlorine mixture.

[Valleybrew]

I have been using unfiltered beer for 10 years, no problems so far. Just make sure you do an adequate precoat since there will be some yeast included in the first coat layers.

[oppigards]

I use just cold water to build up the precoat, then I empty the filter bell with co2, then I fill the mixing chamber with co2, then I fill the bell and mixing unit with unfiltered beer, add DE body coat and circulate it until I get a clear beer. I do not know how much oxygen will be left in the precoat, but I have done like this because I have been worried to get yeast in the pre coat.

[dick murton]

Whether you use beer or water (without chlorine of course - as noted earlier) - don't forget to continuusly bubble CO2 through the slurry to prevent oxygen pickup. I guess if you are using beer to slurry up. it may generate some foam, but I have never used beer, so am not sure if the KG will kill the foam or not.

[oppigards]

i've been told to use a carbonating stone in the mixing tank, (I have not tried that yet) but when I bubble co2 through the mixing unit with a small hose (it has to be beer when dosing bodycoat during filtration) it creates a lot of foam, so I have a hose which continously blow co2 as a blanket over the beer in the mixing unit. It might be not good enough, or?

[Larry Horwitz]

best results we've seen are from slurrying your DE with boiling hot water. It not only saitized the DE, it also pulls out all of the O2. DE carries a ton of oxygen with it for the same reason it is a good filter media...it's full of holes! unfiltered beer may be ok to mix with the DO DE, but you're just adding crud to the cake. If you are going to do it, slurry with Hot Liquor first and then cut with unfiltered beer in the dose tank and make sure you have a nice clean (put on with water) precoat.

BTW, the hot liquor method will not raise the temp of your beer to dangerous levels...and will leave you with the same or LESS DO in your filtered beer!

throw the orbisphere on it...you'll be a convert too.