Sparging: one tier or two ? (Pump phobia...)

[brewman !]

I'm still working on my brewstand design.

Right now we have a 2 tier design, with the mash vessel elevated above the boiler so that the wort drains from the bed under gravity into the boiler during sparge. That is the way I have always done it.

I am considering a 1 tier design where all the vessels would be on the same level. The issue there is that during sparge, one needs 2 pumps. One to pump sparge water from the HLT into the mash vessel and another to pump drained wort from the bed into the boiler. I am speaking of fly sparging, of course.

Pumping the drained wort bothers me. First of all the flow rate can be really low, especially if the bed starts compacting and I am worried that the pump will create a suction in the bed and stick it. I've always gravity drained the bed during sparge.

Do my fears have any basis ?

Thanks.

 

[Monster Mash]

Since you are pumping so slow there is no difference between draining and pumping. I built a 3 tier system because I didn't want to be dependant on pumps. I recirculate through a HERMS with a pump but I go slow enough that it doesn't pull the bed down and stick.

 

[Hopfan]

using a pump toevacuate the wort from the MLT will cause your grain bed to compact unless you have it dialed in just right. (ask me how I know) I haven't built a sculpture yet, but I know that I will not go with a pump out of the MLT.

 

[brewman !]

That is the way I feel too, hopman. I think the mash vessel should gravity drain into the boil kettle.

 

[brewman !]

OK... here is something I don't understand. Lets say we agree that sparging should take say 30 minutes. And we are gathering 6 gallons of wort. That is a pumping rate of 1/6 gallon per minute. What pump pumps that slowly ?

And if it pumps faster than that, isn't it going to create a suction under the bed and contribute to a stuck bed ?

 

[brewman !]

Could one continue recirculating wort with the pump at say 1.5 GPM while sparging and just let the run off into the boil kettle be 1/6 gallon per minute ?

 

[Seveneer]

I use one pump to recirculate the wort through my HERMS system and then when the mash is over I move the output of the pump so that it pumps the wort into the boiler. I then use another pump to sparge.

I've never suffered a compacted mash.

The only thing you need to watch is that you balance the flow through the two pumps. You want to maintain the level of sparge water above the grain so the sparge must match the flow to the boiler.

/Phil.

 

[Mike & John]

You could also use a grant to collect wort from the mash via gravity then just suck the grant out into the kettle whenever it fills up.

grant=little bucket.

 

[Yuri_Rage]

I use one pump to recirculate the wort through my HERMS system and then when the mash is over I move the output of the pump so that it pumps the wort into the boiler. I then use another pump to sparge.

I've never suffered a compacted mash.

The only thing you need to watch is that you balance the flow through the two pumps. You want to maintain the level of sparge water above the grain so the sparge must match the flow to the boiler.

My system is much the same, but I use a two tier system to gravity flow the runnings into the boil kettle while my single pump slowly transfers the hot liquor up through a sparge arm.

This requires that, before sparging, I reconfigure the pump from recirculating the mash to transferring hot liquor, but I don't find it to be very difficult or objectionable.

 

[Yuri_Rage]

Is the reason for recirculating the mash to control temperature (maintain, raise, lower) or to clarify the wort, or both?

Exactly - you can maintain or raise the temperature as required (I suppose you could lower it, though I'm not sure why you'd do that except to correct a gross mistake). A beneficial side effect is that the grain bed sets during the mash (after you've stirred for the last time, of course), so your first runnings are crystal clear.

 

[brewman !]

You could also use a grant to collect wort from the mash via gravity then just suck the grant out into the kettle whenever it fills up.

You could. But its more complexity, more equipment and a greater chance for oxidation.

I think I am going to build a 2 tier system, ala B3-1550, with a tippy, do a slow recirc through my CFC while mashing and then gravity drain to the boiler. The steam injection will do the mash temp steps.

 

[DrewsBrews]

OK... here is something I don't understand. Lets say we agree that sparging should take say 30 minutes. And we are gathering 6 gallons of wort. That is a pumping rate of 1/6 gallon per minute. What pump pumps that slowly ?

And if it pumps faster than that, isn't it going to create a suction under the bed and contribute to a stuck bed ?

You can control the flow rate of the pump with a valve on the output side. I plan on doing this and adding a grant into the system to visually monitor what comes out of the tun. The grant will be fed totally by gravity. If the liquid level in the grant starts to decrease rapidly, I'll know to throttle down the valve on the pump until the grant starts to fill back up. No stuck mashes that way and I can have the tun and the kettle on the same tier.