Recirculation rate - HERMS/RIMS

[Kev888]

In another thread I'm heading (painfully slowly) towards an upward recirculation system, but its becoming clear that there's a lot of complexity and a fair amount of compromise in recirculating upwards. I'm sure I could cope if its worth it, but it is making me wonder if the compromises are justified.

Could I ask people with more experience of RIMS or HERMS if you ever feel a faster recirculation could actually help or not - either just normally or for stepping and mashout?

Also, has anyone found a 'particularly' free-draining design of false bottom? I'm thinking maybe a carefully made slotted FB or something like that could go some way to getting a decent throughput.

Many thanks
Kev

[barneey]

Kev, If I ever finish this building malarkey and get a brew day I will let you know how the blichmann FB gets on

[Kev888]

Thanks! It sounds like you're getting fairly close, in the scheme of things.

Cheers
kev

[swiggingpig]

I use a Brupaks enamel MT/boiler along with a Totton pump and a PID as my RIMS system. A Brupaks wire rack is placed in the MT which rests on the back nut of the tap and I use a Brupaks grain bag. I'm sorry about the quality but here are a couple of quick photo's I took as I left for work this morning.





I find that I need to use a high water ratio of at least 3.5 - 4 to 1, preferably 4 - 5 to 1, and a gentle recirculation in order to avoid compacting the grain bed.

The probe is positioned at the outlet from the the MT, just after the wort has flowed across the heating element. I find that with an average mash of around 4kg malt and 16lt of water I can get a temp rise of around 1 degree per minute.

I put hot tap water, around 50C, into the MT along with the grains, I then use the PID to bring it up to mash temp and start timing my 60 min mash from then.

I mash out at 78C, this step takes about 10 mins, and to save time I do a single batch sparge which I recirc for about 5 mins which gives me an efficiency of around 72%, which I'm happy with.

I'm sure a fly sparge would give me better efficiency but I feel it is a fair trade for the time saved as I normally do double brew days.

[Kev888]

Excellent, many thanks for all the info - thats mopst helpful!

Its also very good to hear the trade between efficiency and time is a fair one - thats exactly what I was hoping, too!!

Cheers
Kev

[Andy]

Wet mash seconded! I recirculate fairly slowly on my RIMS system as the heater is a 800W towel rail element and too fast a recirc would mean the element would never have any impact and the PID would end up leaving it 100% switched on

[Kev888]

Many thanks, Andy. That makes sense - its all starting to come together in my head

Think I need to do some heating-time calculations, too.

Cheers
kev

[Kev888]

Whilst I'm on the subject, I just wanted to check - am I right in thinking you can't boil with a RIMS? It would just make my boiler design easier if i could use an external element...

Cheers
Kev