fly sparge question

[missing link]

I just tried using a rotating sparge arm for the first time. The bottom of my HLT was about a foot above the top of my MT. In order to get the arm to spin I had to flow so much water that I used all my sparge water in 10 minutes instead of 60. How do you guys get a 60 min sparge using the roatating arm? I was sparging almost 6 gallons of water.

Linc

 

[Bobby_M]

We batch sparge instead. Hehe, just a little tongue in cheek boss ;-)

 

[missing link]

I guess in a way I batch sparged with a fly sparge arm. is that a flying batch sprage then?

 

[Brew-boy]

No sure about the rotating sparge arms, I built my own that sits inside my cooler.
I make the sparge last an hour with the same out flow as the in flow to the MLT.
I love this design as I can sparge with the lid closed to keep my temps at 175 or so.

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[Bobby_M]

I don't really know what a flying batch is. The two methods are pretty distinct in that batch requires stirring the water/grain to achieve a sugar equilibrium. Flying requires an even plane of water flowing down through the grain bed.

 

[missing link]

It was a bit of a joke. I meant to fly sparge but the spinning gadget needs to much flow to spin. I think I am going to back to a PVC type manifold to sit on top of the grain so I can reduce the flow as much as I need.

 

[missing link]

Either way, I just got it in the fermenter and hit my OG target right on. My pre-boil gravity was low so I boiled and extra 30 minutes.

Linc

 

[drayman86]

I just tried using a rotating sparge arm for the first time. The bottom of my HLT was about a foot above the top of my MT. In order to get the arm to spin I had to flow so much water that I used all my sparge water in 10 minutes instead of 60. How do you guys get a 60 min sparge using the roatating arm? I was sparging almost 6 gallons of water.

Linc

Don't get too hung up on the sparge arm spray when conducting fly sparging.

It seems experts agree that a level of about 2 inches of water above the grain bed is most important.

Think about what fly sparging is trying to accomplish; slow perculation of sparge water down through the grain bed. It's REALLY slow; most sources indicate about a 1 QUART per MINUTE. (That's freakin' slow.) Like about a pencil-sized diameter out of your kitchen sink water faucet, probably less.

Sparge spray arms are attempting to enusre that the sparge water heat is evenly distributed in a vertical fashion as it flows down through the grain bed.

You would have to create an extreme situation in fly sparging at the above rate (1 qt./min.) for this NOT to occur. Kinda' like peeing in one small spot in a toilet bowl. Just don't concentrate the sparge water out of a hose at too great a rate into one small location in the mash tun, and fly sparging will work well without the sprayer.

Measure the fly sparge rate; go ahead ! Shoot for about 1 qt./min. and use a piece of heavy aluminum foil on top of the mash (with many holes) to distribute the sparge water over the top surface of the grain. Just get that 2 inch depth on top of the grain, even out the inflow and outflow to the mash tun, and fly sparging will help you achieve better efficiencies.