Recirculating Mash

[Hogan]

I've seen a number of 'arms' that are used in the recirculation of mash to clear it prior to mashing out or sparging. They seem to be mostly manifolds that redistribute the runnings across the top of the mash until they are seen to be clear, the recirculation stopped and the run-off commenced.

Are these arms really necessary for recirculating?

Could not the top inlet for the recirculation be mounted below the high mash level and the runnings pumped back into the mash without the need for 'arms'. The pressure of the March Pump should stop any flow-back and the fact that the recirculation is going in below mash level should alleviate HSA. Obviously the top inlet would require a ball value which would be turned off with the cessation of pumping.

A top inlet mounted at a level below the lowest predicted mash level would also remove the necessity for 'adjustable heights' for recirculation arms.

This is not meant to apply to fly sparging.

Have I got this recirculation business all wrong or what??


Cheers, Hoges.

 

[Jye]

A return manifold isnt really that important and what your proposing could very well work. I think it is Justin who just lays a length of silicone tube on top of the mash and recirculates through that, you cant get more simple than that.

 

[Hogan]

A return manifold isnt really that important and what your proposing could very well work. I think it is Justin who just lays a length of silicone tube on top of the mash and recirculates through that, you cant get more simple than that.

Jye - why does it have to lay on top of the mash? Ok, if it was coming in over the lip of the tun that's understandable. But... if the recirculation is being injected through the tun wall what is to stop that injection going directly into the mash below its high level rather than being splashed on the surface.

Cheers, Hoges.

 

[matti]

Look hereLinky.
The actual recirculation copper manifold is meant to be kept under the surface.
I think you are right on thr money here.
I am no expert in equipment but I think it may be worth to a put a ball valve at entry point to mash if you don't have the manifold.
matti

 

[therook]

Look hereLinky.
The actual recirculation copper manifold is meant to be kept under the surface.
I think you are right on thr money here.
I am no expert in equipment but I think it may be worth to a put a ball valve at entry point to mash if you don't have the manifold.
matti

That links not working for me matti?

rook

 

[Jye]

It would be undesirable to inject the recirculated mash downwards, this would disturb the mash bed (grain filter) and the recirc would not clear. If this was happening then a manifold of some type would be need to redirect the recirc upwards.

 

[matti]

sorry not for me either but ckeck the grain and grape web site herms systems . http://www.grainandgrape.com.au/articles_o.../gg_herms01.htm
There a picture of the copper manifold and the text explains

 

[Hogan]

It would be undesirable to inject the recirculated mash downwards, this would disturb the mash bed (grain filter) and the recirc would not clear. If this was happening then a manifold of some type would be need to redirect the recirc upwards.

It would not be injecting downwards - just sideways. The small amount of pressure exerted by the March pump should not affect the grain bed when you consider the mash depth, even in a converted keg.

Cheers, Hoges.

 

[Screwtop]

It would not be injecting downwards - just sideways. The small amount of pressure exerted by the March pump should not affect the grain bed when you consider the mash depth, even in a converted keg.

Cheers, Hoges.

Correct Hoges, mine runs down under the liquid level and then sideways around the inside of the tun, a bit like whirlpooling, no problem with clear wort, as a matter of fact it improved my run off, used to get that mud/sludge over the top of the grainbed which slowed/stopped the run off. Recirculating during the rest results in beautiful clear wort, mash out is simply directed to the kettle instead of the MLT return.

Screwy

 

[deckedoutdaz]

This link will work...

www.grainandgrape.com.au/articles_other/gg_herms01.htm

Daz

 

[Tony]

I am guessing you are talking about a fixed return in the tun as aposed to the sparge arm most of us use that go through the top or lid to return the wort.

QUestioning the institution hey...... I LIKE IT

I did origionally plan to do just this, even mounted a very basic verson but it got in the way when i opened it up to stir the mash or remove the spent grain after the mash

I have mine mounted in the lid so when i remove the lid , it comes out with it, giving me unrestricted access to the mash.

Also if it blocks up for some reason (had it once when an experimental false bottom buckled) its easy to lift out, backflush and return to the brew in a few minuites.

have you ever had to go elbow deep in a 66 deg mash.

I have!

Try it some time..... i dont want to

thats why i made mine come in through the lid to make it easy to remove.

apart from that there is no real science in it.... just what works for me

cheers

 

[ant]

I have a sparge arm that sits ~6-12 inches above the mash, but delivers only water from the HLT during mash-in and sparging. I recirculate continually for the duration of the mash, exiting from a ball valve underneath the false bottom, and coming back to a full coupler in the top of the MLT. I went for a full coupler as it meant I could put a quick disconnect on the inside of the MLT, which allows me flexibility to change the setup, but currently it has a length of silicone hose which goes around the side of the MLT and sits about an inch or so below the level of the mash. Also easier to remove to pull out the false bottom and clean, etc

 

[Justin]

Yeah Hogan, you are on the money in that there is no real science in it-anything will work and what you are proposing would work I'm sure. The only down side I can see is that you are kind of locked into the size of your mash (via the height of the mash). Obviously this depends on your mash tun and how much you vary your mash size, on a big batch you might end up feeding the recirc back into the middle of the grain bed a bit if your return is set up for 5 gallon batches for example. Depends on how you have set up your system and its size etc and if you do batches of varying size.

I do only use a length of silicone hose now I'm batch sparging and it self levels beautifully by itself when I'm recircing, however even if I was fly sparging the hose would work fine as well without a manifold (however I did have one like everyone else when I was fly sparging but now that I have set up a HERMS and recircing constantly I've come full circle again and I'm back to using a very simple manifold-not much more than a T piece in the end of a hose).

Don't know about you guys but when I was fly sparging and also recircing to set the grain bed before run off the rate at which the return/sparge water was entering the top of the tun it was never going to bore a hole to China in my grain bed.

I've found in actual use it is pretty hard to upset the grain bed, as in my mash tun the depth prevents any disturbance in the upper portion getting down to the bottom. I use the old 50L stainless MT variety . When batch sparging obviously it doesn't matter how your water gets in there, and honestly it doesn't take much to set the bed and start getting a clear run off when you recirc so you don't really need elaborate return mechanisms unless you have a "really" shallow grain bed.

What do you propose to be the real advantages of setting your recirc up in this way through the side over just setting up a conventionl mechanism? I have no problems with your idea, like Tony I'm keen to see new thoughts and idea etc, but I'm not sure if you will gain too much advantage over the traditional method of doing it. I agree it might be simpler than height adjustable return manifolds but as a few have suggested above about the height adjustable manifolds, nice but not totally necessary.

Some of the downsides I could see in your design are 1. not being able to see the flow rate of your return by checking the output, you'll be flying blind on exactly what your flow rate will be out of the pump. 2. If your flow stops and you get a stuck run off, unless your height is perfect and you an see the current of water/wort flowing back into the tun you might not be able to see it easily straight away (I'm always pulling my hose out of the surface to check the speed it's flowing at). Worth thinking about as that might sway you one way or the other?

If you are worried about rigging up a mechanism to come through your lid, why not do it how I have which is basically exactly what you have proposed but I've come back in the side of the tun nearer the top. That suits any size mash and you can just use the hose to get down to your bed height. Just don't use a hose that is too short so it shoots directly into your bed, a bit of extra length is good here so it lays on the top and directs the flow from driving straight in. You can see what I'm talking about here: http://hbd.org/discus/messages/366/33903.html?1187582191

Happy to keep the discussion up. Nice to see a good brewing related topic to chat about.

Cheers, Justin

 

[Stuster]

Just to play devil's advocate, I'd just like to point out that there may not be such a huge need for recirculating. Research in the last ten years seems to show that getting a crystal clear run-off is not the benefit it was thought to be. I'm certainly not saying it will hurt your beer to do it, but it may be of little or no benefit. Now if you feel better doing it, then go right ahead, but just don't say I didn't try to save you some work.

If anybody's interested in reading a load of science :blink: the study is here. Basically, the study showed that there was almost no difference between beers made with clear or turbid wort from the lauter tun. Taste tests were the same, clear wort beers kept slightly better, but fermentation and head retention were better from the cloudy wort.

Anyway, as I say, not to put you off if you want to do this, more to reassure people that there's no need to go crazy getting crystal clear wort. As long as you keep the big bits out of the boil, you'll be fine.

 

[Sammus]

My first HERMS attempt didn't even get me crystal clear runoff... it was clear sure, clearer than the first litre of runoff from my non herms batches.... And i was recirculating super slow with a manifold of sorts that didnt disturb my grainbed (which was also quite deep, given my 50L s/s type of mash tun)... only thing I got from it was temp stability and a 10% drop in efficiency (i'm pretty sure that was due to something else though)

 

[Lukes]

I use the silicone hose and copper elbow's method too.
You can see it sinks a little into the mash in a 50 ltr tun.
Batch sparge.

- Luke

 

[devo]

i don't bother with a manifold anymore. I simply use a single piece of hose and get a pretty clear run off after a 15 minute reticulation.

 

[razz]

When it comes to recirc during the mash I'm with Stuster on this one. I haven't done it for sometime now and it hasn't had a negative effect on my brews. In fact, I find I'm getting more consistent results with efficiency. I only bother to recirc through the herms for mashout.

 

[SJW]

After seeing what they use up at Potters Brewery I stopped worrying about my system. At Potters in the Mash Vessel they use what could only be decribed as a glof ball shaped shower head that sprays water from a great height.(Maybr Scotty could expand a bit more on this) So with my 2 inch fall from a copper pipe with a splayed end on it, and valve controled from the pump I dont think it is such a big deal how u do it!

Steve

 

[Zizzle]

Hogan I've done exactly what you have suggested before with my brewbot.

Check out my Keep Cold mash tun:

I didn't want to put a hole in the lid since I plan to move away from this tun eventually and sell it on.

So I pulled out the thermometer out and put the hose into there, which you can see is pretty low on the tun.

I don't have HERMs setup yet, so have programed the 'bot to just do a 1 minute recirc at the end up the mash/sparge to clear up the wort.

I have a flow switch in the wort loop so I can still tell if a sparge is stuck.

I'm hoping that having clearer wort at sparge time means less trub in the kettle at the end (and so less loss) but haven't really tested the difference.

But so far, despite reentry being quite low in the grain bed, it seems to clear up the wort nicely.