Continuous RIMS no-sparge v. Fly Sparge

[jwbeard]

I'm planning my first brew on a new direct-fire RIMS system (15 gallon kettle doubling as a mash tun with a false bottom, and a 8 gallon kettle used as either a grant for the RIMS circulation or as a HLT for the sparge).

I remember seeing a system being described (and cannot, for the life of me, find a thread or webpage describing it now), where the wort was circulated continuously during the mash and then drained completely during mash-out. Effectively, I think it was a high efficiency no-sparge system (since the ability to heat during the mash and circulate made the wort a consistent gravity, even if the lack of a sparge left some residual sugars).

My question is how substantial the efficiency hit would be if I implemented the system above, and did the following:

• Dough-in to the 15 gallon mash tun kettle
• Gravity feed to the 8 gallon grant kettle
• Pump from 8 gallon grant through a sparge arm back onto the mash
• Circulate until the end of the mash
• Mash out by raising to 168
• Drain and begin boil

Alternatively, if there's a big efficiency loss, I could add a step at the end before draining

• Drain grant kettle completely into mash tun and let mash sit at 168
• Add and heat sparge water to grant kettle (now HLT)
• Fly sparge and collect wort

Any benefits to doing the continuous no-sparge method? Is it worth doing the additional fly sparge steps?

 

[acidrain]

I've done the direct fired RIMS, but not no-sparge. Take this for what it's worth...
Doing step mashes or even just trying to maintain a certain temp can easily result in a scorched batch with direct flame.
There is no need to mash out when batch sparging, so raising the temp to 168F in your first example is not necessary.
I don't use a grant. I have had stuck mashes, but once I got a feel for how far to open the valve, no more stuck mashes. I don't see a reason for a grant. I would use a vacuum gauge at the inlet side of the pump instead if you really wanted to.
I think you would suffer efficiency by doing a no-sparge, but can't really say how much.
Looking at your second scenario, I think you have confused fly sparging with batch sparging...
Batch sparging is draining completely, adding more sparge, then draining again. Batch sparging happens quickly, and there is no need to mash out.
Fly sparging is done slowly where you are adding water at the same rate as you are draining. This is the only time you denature the enzymes by raising the temperature (mash out). It may take an hour to do a fly sparge.

The bottom line is, try some things and figure out what works for you. Sift through the information out there and learn as you go.

 

[jwbeard]

Sorry for the confusion - batch sparging was never part of the contemplated process. The grant was only being used as a grant in the first scenario; in the "additional steps" section I was trying to describe that I would (at the end of the mash/mash-out but before the sparge) empty the grant into the mash tun so that all of the wort was in the mash tun. I would then add fresh water to the grant-now-HLT, heat it to 170, and fly sparge by continuously feeding it to the top of the mash tun.

Going to keep the direct-fire heat low during the mash-out to avoid scorching, but do typically do a mash-out in order to lock in the sugar profile and lower the mash viscosity.

I'm going to give it a go for the next brew - I'll report back and let everyone know how it goes!

 

[rogerj]

After scouring the net looking for this exact topic I finally found your thread. I want to do the same thing:
2 pots, MLT and BK.
Bring Strike water to temp in MLT, add grain, and immediately start fly sparging with a rims tube. I'm surprised more people don't do this. What were your results?

 

[mjohnson]

Lookup Brutus 20 - is that what you are trying to describe? I have a 2 vessel system. I mash like normal in my cooler, heat "sparge" water, after mashing, I start to recirculate the entire volume while heating to mashout. When the entire volume is at the same gravity, I just drain into the kettle and boil.

I tend to get about 70% efficiency this way.

 

[jwbeard]

After scouring the net looking for this exact topic I finally found your thread. I want to do the same thing:
2 pots, MLT and BK.
Bring Strike water to temp in MLT, add grain, and immediately start fly sparging with a rims tube. I'm surprised more people don't do this. What were your results?

Results were pretty sub-par for my test batch (66.9% efficiency), though I'm almost positive that was due to my failure to take the deadspace in the mash tun into account. By the time the void under the false bottom was filled (~2 gallons), there was barely enough water to cover the grains, so I was at a very very low water:grain ratio. The wort was super clear (though, I ended up having to do a batch sparge to get more wort, which ended up clouding the hell out of the boiled wort).

Doing my first 10 gallon batch this weekend, and have built a handy little spreadsheet (in Numbers.app) that tracks literally everything in the boil (BeerAlchemy didnt let me tweak some key settings... So, I just programmed my own ).

Lookup Brutus 20 - is that what you are trying to describe? I have a 2 vessel system. I mash like normal in my cooler, heat "sparge" water, after mashing, I start to recirculate the entire volume while heating to mashout. When the entire volume is at the same gravity, I just drain into the kettle and boil.

I tend to get about 70% efficiency this way.

That's the one! I'm not going to do this on my batch this weekend, since I need to dial-in all the variables before I can accurately determine how much extra wort should be sitting in the BK/grant at any given time during the continuous recirculation. Once I manage to calculate those values, though, I'll give it a try.

Thanks!

 

[mjohnson]

Just curious, why do you need a grant? I just pump from the output of my mash tun.

 

[jwbeard]

As it turns out, it appears I don't (and didnt use one during the last batch). I had read someplace online that the suction from the pump could cause the grain bed to compact, which could cause a stuck sparge. Didnt seem to be an issue on my batch though.