sparging questions

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SAS98M

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A few questions pertaining to the subject if I may...
1- fly sparging or batch sparging-what and why ?
2-amount of wort or water to use when sparging-how much and why ?
3-efficiency achieved when sparging-what,how much to expect,how to achieve and why ?

I've just done my 1st extract brew (Munich lager)a few hrs.ago-all went very well-no surprises,no boil-overs,primaried/yeast pitched-no problems to speak of. To me a lot easier than I expected.I am interested in AG brewing and just trying to grasp all the additional steps involved,I have a good propane burner,I'm in the process of assembling a keggle,have a few plastic coolers laying around.I've seem some of the advanced brewing tiers and don't quite understand all that's involved-pumps,liquer tanks heat exchangers and all that. I have figured -I think-that the mash tun and its function is a longer version of what the steeping of the grain bag does in the extract brew-the rest I'm sorry to admit is a little ways out..... I've seen a lot of advanced brewers here,a lot of advanced brew set-ups,a few real simple,some even intimidating at this point so-these questions aren't to pester so please bear with me.... I want to hear and see this in theory and think I'd rather go down the AG road albeit mini-mash or full mash and start another batch really soon-probably an Ale. Any info pertaining will be appreciated. Shane
 

UTDoug

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I'd like to tack on a question about sparging as well - I've never done AG, but I've read you should use about 50% more water for sparging than you do for mashing. So if I'm doing a 5 gallon batch with, say, 12 lbs of grain and I'm supposed to use 3 gallons to mash that, then I'd end up with around 7.5 gallons of water. Am I supposed to boil off those extra 2.5 gallons??? That'd take forever!
 

Orfy

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www.howtobrew.com

1- fly sparging or batch sparging-what and why ?

You need to read up and decide yourself.
I batch sparge and have no plans to change, other fly sparge and will not batch.
Depends on objectives, equipment, style of beer, ingredients, how much time to have, If you like to be hands on, how much flexibility you have

2-amount of wort or water to use when sparging-how much and why ?


You need to read up on the formulae to work it out. Just about every how to brew web sit and book explains it. I sparge to volume or down to 1010 gravity


3-efficiency achieved when sparging-what,how much to expect,how to achieve and why?

It depends on many things and you want the most sugar from the grain without tannins. All the how to brew sites and books explain.

The people on here who know this will of read many such articles to find the answers.Once you have the basics, not just the terminology then it is much easier to ask specific questions rather than one that requires a full lesson in brewing.

Sorry if it sounds a little arsey but Making good beer takes patience and that includes doing a little reading and research. Take a little look at my website or the many others that people have taken time to put together to explain such things.
 

Orfy

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There are lots of info around some of it really easy.

But if you want to know what is actually involved then here's a little exert I've had to reduce it to allow the post to 10000 characters instead of 30000+ from Ken Schwartz
Full piece here.:http://home.elp.rr.com/brewbeer/files/nbsparge.html

What you will determine is the following:
"S", the grain scale-up factor (the weight of each grain in the standard recipe is multiplied by "S" to obtain the no-sparge or batch-sparge recipe),
"Wg", the total weight of grain needed for the no-sparge or batch-sparge version,
"R", the required mash thickness at runoff,
"Vm", the total volume of mash water that has been put into the mash tun to achieve "R" at the first runoff,
"V1", the first runoff volume (equal to your "Vb" if no-sparge brewing),
"G1", the gravity of the first runoff,
"Vs", the required volume of "sparge" water to be added after the first runoff (if batch-sparge brewing),
"V2", the second runoff volume ( if batch-sparge brewing),
"G2", the second runoff gravity (if batch-sparge brewing),
"Vt", the total mash-tun capacity required to hold all the grain and water.
A note on "gravity" figures. Ideally you should use a gravity scale that is based on percentage of sugar, such as the Plato scale. You can use specific gravity "points", which are the digits following the decimal place in specific gravity (1.045 SG = 45 "points"), but there will be a slight error since SG does not correspond exactly linearly with sugar content. In any case, do NOT use specific gravity in the form 1.XXX, it will NOT work in these formulas!
You can use any units in these equations, as long as you use them throughout all the calculations. Please note that if you use gallons and pounds, the mash thickness "R" will also be in units of gallons per pound, not the more often used quarts per pound. Multiply gallons per pound by four to convert to quarts per pound if desired.
Grain occupies about 0.08 gal/lb (0.67 l/lb) when mixed with water. Call this figure "Q" and use it to find Vt, the total mash tun volume (capacity) required for the scaled-up recipe.
The Equations

For a no-sparge recipe:

S = Vb / (Vb - (Ra x Wn))
G1 = Vr x Gr / Vb
R1 = Ra x S / (S - 1)
Wg = S x Wn
Vm = (Ra + R1) x Wg
Vt = Vm + (Q x Wg) To minimize the extra grain required, collect as much wort as possible by establishing a thin mash just before runoff. Again, it's probably better to mash using a "normal" mash thickness, and thin the mash to "R" only after the conversion is complete.
When batch-sparge brewing, it turns out that the best extraction efficiency is obtained when the two runoffs are of equal volume (V1 = V2 = Vb/2):

R = (Vb + SQRT{Vb2 + (8 x Wn x Vb x Ra)}) / (4 x Wn)
S = 1 / (1 - (Ra2/R2))
Wg = S x Wn
Vm = R x Wg
V1 = Vb /2
G1 = S x Vr x Gr / (V1 + (Ra x S x Wn))
Vs = V1
V2 = V1
G2 = Vr x Gr x (Ra/R) x (1 - Ra/R) / (Wn x (R - Ra))
Vt = Vm + (Q x Wg) "SQRT{}" means take the square root of the expression inside the curly brackets {}
For a full explanation of the math behind these equations, see the sidebar.

Definition of Variables Used in the Analysis -- Mash Conditions
Vr = recipe volume (can be more or less than available boiler capacity)
Gr = recipe gravity (expressed as "points/unit volume"; see below)
Vb = total volume to be sparged to boiler (there will be one runoff for no-sparge, two runoffs for batch-sparge)
E = standard continuous-sparge extraction efficiency (range 0 to 1, or percent ÷ 100)
Wn = weight of grain of the standard recipe
Wg = weight of grain of the no-sparge or batch-sparge recipe
Ra = absorption rate of the grain
R1 = final mash water volume to grain weight ratio (just before first runoff)
R2 = desired sparge water to grain ratio (just before second runoff, after sparge infusion and rest, batch-sparge only)
Ptn = total potential extract points of the standard recipe (see below)
Pt = total potential extract points of the no-sparge or batch-sparge recipe (see below)
Analyzing the Mash

Now we can analyze the process to find all the other relevant factors:
Definition of Variables Used in the Analysis -- Recipe Results
Pn = predicted total extracted points for the standard recipe
Pa = predicted total extracted points for the no-sparge or batch-sparge recipe
Vm = total volume of mash water (at time of runoff)
Va = total volume of liquid absorbed by the grain (or not otherwise removed from the tun)
V1 = volume of first runoff (it's the only runoff if no-sparge)
G1 = gravity (points per unit volume) of first runoff
P1 = total points in first runoff
Pm = total points remaining in mash tun (in the liquid absorbed by the grain) after first runoff
Vs = volume of sparge water added to mash after first runoff (batch-sparge only)
V2 = volume of second runoff (batch-sparge only)
G2 = gravity of second runoff (batch-sparge only)
P2 = total points in second runoff (batch-sparge only)
Ps = total points remaining in mash tun (in the liquid absorbed by the grain, or not otherwise removed from the tun) after second runoff (batch-sparge only)
Gb = gravity (points) of boiler contents after both runoffs (batch-sparge only)
Pb = total points in boiler kettle after both runoffs (batch-sparge only)
Just before recirculation and runoff, there will exist a certain water to grain ratio (mash thickness) R1 which is directly related to the total quantity of mash water used(Vm):
Vm = R1 x Wg
The gravity of the first runnings (in points per volume) is by definition the total actual points divided by the mash water volume:
G1 = Pa / Vm
The portion of the total mash water volume which is absorbed by the grain (more accurately, that which is left behind after the runoff) is
Va = Ra x Wg
For the first runoff volume V1, we will drain off all the liquid except that which is absorbed by the grain:
V1 = Vm - Va
= (R1 x Wg) - (Ra x Wg)
= (R1 - Ra) x Wg
P1 / Pa = V1 / Vm
P1 = Pa x V1 / Vm
= Pa x ((R1 - Ra) x Wg) / (R1 x Wg)
= (1 - Ra / R1) x Pa
The number of points remaining in the mashtun after the first runoff is
Pm = Pa - P1
= Pa - (1 - Ra / R1) x Pa
= (Ra / R1 ) x Pa
I
As with the first runoff, the number of points in V2 is the same as the proportion drained versus the total volume so
P2 / Pm = V2 / (V2 + Va)
P2 = Pm x Vs / (Vs + Va)
= Pm x (R2 - Ra) x Wg / ((R2 - Ra) x Wg + Ra x Wg)
= Pm x (1 - Ra / R2)
and the runoff gravity is
G2 = P2 / V2
The proportion of sugar left in the mash tun after sparging is the same proportion as the remaining (absorbed) liquid:
Ps / Pm = Ra / R2
Ps = Pm x (Ra / R2)
= Pm x (Ra / R2) x (Ra / R1)
= Pm x (Ra2 / (R1 x R2))
In the boiler, then, we now have a volume
Vb = V1 + V2
with a total number of points
Pb = P1 + P2
and therefore a gravity of
Gb = Pb / Vb
Optimizing the Batch-Sparge Process

Let's digress for a moment and see if we can optimize the extraction of sugar into the boiler for the batch-sparge case. The total number of points we put into the boiler was Pb = P1 + P2
= (1 - Ra / R1) x Pa + (1 - Ra / R2) x Pm
= (1 - Ra / R1) x Pa + (1 - Ra / R2) x (Ra / R1) x Pa
= Pa x [(1 - Ra / R1) + (1 - Ra / R2) x (Ra / R1)]
= Pa x (1 - Ra2 / (R1 x R2))
so from the above relationship,
S = Pa / Pb
= 1 / (1 - Ra2 / (R1 x R2))
Unfortunately at this point, we don't yet know the values of R1 and R2, so we can't evaluate S numerically. But we'll get there!
Let's take another look at
Pb / Pa = 1 - (Ra2 / (R1 x R2))
Since this represents the "batch-sparge efficiency", it is the expression we want to maximize. If you took calculus you might remember that to minimize or maximize a function, you must differentiate it with respect to the independent variable of interest, then set that expression equal to zero. However, we have two variables, R1 and R2. But, note that these variables are related in that we are obtaining a fixed volume of wort Vb, and therefore R2 depends on R1. Rewriting the expression for Vb in terms of R1 and R2, we see that
Vb = V1 + V2
= (R1 - Ra) x Wg + (R2 - Ra) x Wg
= (R1 + R2 - 2Ra) x Wg
Rearranging, we can write R2 in terms of R1:
R2 = (Vb / Wg) + 2Ra - R1
To maximize the batch-sparge efficiency expression, it is sufficient to maximize just the product R1 x R2. Rewriting R1 x R2 using the last equation,
R1 x R2 = R1 x ((Vb / Wg) + 2Ra - R1)
or
R1 x R2 = ((Vb / Wg) + 2Ra) x R1 - R12
We differentiate this expression with respect to R1 and set it equal to zero to maximize:
Vb/2 = Wg x (R - Ra)
Since Wg = S x Wn and S = 1 / (1 - (Ra2 / R2)),
Vb/2 = S x Wn x (R - Ra)
= Wn x (R - Ra) / (1 - (Ra2 / R2))
= Wn x (R - Ra) x R2 / (R2 - Ra2)
Rearranging,
Vb/2 x (R2 - Ra2) = Wn x (R - Ra) x R2
The difference of two squares on the left side is rewritten:
Vb/2 x (R - Ra) x (R + Ra) = Wn x (R - Ra) x R2
Dividing through by (R - Ra),
Vb/2 x (R + Ra) = Wn x R2
So
0 = Wn x R2 - Vb/2 x R - Vb/2 x Ra
= 2 x Wn x R2 - Vb x R - Vb x Ra
which is a quadratic in R with two solutions
R = (Vb +/- SQRT{Vb2 + 8 x Wn x Vb x Ra}) / (4 x Wn)
where everything inside the curly brackets after "SQRT" is considered to be under a square-root radical.
Note that the quantity under the radical is always greater than Vb. Since we need R > 0 (negative values for R don't make real-world sense!), the only root that "works" is
R = (Vb + SQRT{Vb2 + 8 x Wn x Vb x Ra}) / (4 x Wn)
This gives us all we need to design an optimum batch-sparge session.
 
OP
S

SAS98M

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Hey Orfy-I'm really outa wack now-after reading that I'm cross eyed and my brain feels as though it's gonna blow thru my temple-Holy cow. I was just lookin' for the simplest info. Shane
 

rod

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orfy you make me ashamed with all that info. - i am very basic - i start with 10 gallons of water
i add 11 pounds of grain to my cooler and water to get the temp to about 152 degrees. stir
sit one hour - drain.
add 170 degree water till cooler is full, stir and sit 10 minutes
drain and repeat until i have used up all the water.
carry pot outside and boil
i have much to learn oh yoda!
 

Hopfan

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orfy said:
[/I]What you will determine is the following:
"S", the grain scale-up factor (the weight of each grain in the standard recipe is multiplied by "S" to obtain the no-sparge or batch-sparge recipe),
"Wg", the total weight of grain needed for the no-sparge or batch-sparge version,
"R", the required mash thickness at runoff,
"Vm", the total volume of mash water that has been put into the mash tun to achieve "R" at the first runoff,
"V1", the first runoff volume (equal to your "Vb" if no-sparge brewing),
"G1", the gravity of the first runoff,
"Vs", the required volume of "sparge" water to be added after the first runoff (if batch-sparge brewing),
"V2", the second runoff volume ( if batch-sparge brewing),
"G2", the second runoff gravity (if batch-sparge brewing),
"Vt", the total mash-tun capacity required to hold all the grain and water.
A note on "gravity" figures. Ideally you should use a gravity scale that is based on percentage of sugar, such as the Plato scale. You can use specific gravity "points", which are the digits following the decimal place in specific gravity (1.045 SG = 45 "points"), but there will be a slight error since SG does not correspond exactly linearly with sugar content. In any case, do NOT use specific gravity in the form 1.XXX, it will NOT work in these formulas!
You can use any units in these equations, as long as you use them throughout all the calculations. Please note that if you use gallons and pounds, the mash thickness "R" will also be in units of gallons per pound, not the more often used quarts per pound. Multiply gallons per pound by four to convert to quarts per pound if desired.
Grain occupies about 0.08 gal/lb (0.67 l/lb) when mixed with water. Call this figure "Q" and use it to find Vt, the total mash tun volume (capacity) required for the scaled-up recipe.
The Equations

For a no-sparge recipe:

S = Vb / (Vb - (Ra x Wn))
G1 = Vr x Gr / Vb
R1 = Ra x S / (S - 1)
Wg = S x Wn
Vm = (Ra + R1) x Wg
Vt = Vm + (Q x Wg) To minimize the extra grain required, collect as much wort as possible by establishing a thin mash just before runoff. Again, it's probably better to mash using a "normal" mash thickness, and thin the mash to "R" only after the conversion is complete.
When batch-sparge brewing, it turns out that the best extraction efficiency is obtained when the two runoffs are of equal volume (V1 = V2 = Vb/2):

R = (Vb + SQRT{Vb2 + (8 x Wn x Vb x Ra)}) / (4 x Wn)
S = 1 / (1 - (Ra2/R2))
Wg = S x Wn
Vm = R x Wg
V1 = Vb /2
G1 = S x Vr x Gr / (V1 + (Ra x S x Wn))
Vs = V1
V2 = V1
G2 = Vr x Gr x (Ra/R) x (1 - Ra/R) / (Wn x (R - Ra))
Vt = Vm + (Q x Wg) "SQRT{}" means take the square root of the expression inside the curly brackets {}
For a full explanation of the math behind these equations, see the sidebar.

Definition of Variables Used in the Analysis -- Mash Conditions
Vr = recipe volume (can be more or less than available boiler capacity)
Gr = recipe gravity (expressed as "points/unit volume"; see below)
Vb = total volume to be sparged to boiler (there will be one runoff for no-sparge, two runoffs for batch-sparge)
E = standard continuous-sparge extraction efficiency (range 0 to 1, or percent ÷ 100)
Wn = weight of grain of the standard recipe
Wg = weight of grain of the no-sparge or batch-sparge recipe
Ra = absorption rate of the grain
R1 = final mash water volume to grain weight ratio (just before first runoff)
R2 = desired sparge water to grain ratio (just before second runoff, after sparge infusion and rest, batch-sparge only)
Ptn = total potential extract points of the standard recipe (see below)
Pt = total potential extract points of the no-sparge or batch-sparge recipe (see below)
Analyzing the Mash

Now we can analyze the process to find all the other relevant factors:
Definition of Variables Used in the Analysis -- Recipe Results
Pn = predicted total extracted points for the standard recipe
Pa = predicted total extracted points for the no-sparge or batch-sparge recipe
Vm = total volume of mash water (at time of runoff)
Va = total volume of liquid absorbed by the grain (or not otherwise removed from the tun)
V1 = volume of first runoff (it's the only runoff if no-sparge)
G1 = gravity (points per unit volume) of first runoff
P1 = total points in first runoff
Pm = total points remaining in mash tun (in the liquid absorbed by the grain) after first runoff
Vs = volume of sparge water added to mash after first runoff (batch-sparge only)
V2 = volume of second runoff (batch-sparge only)
G2 = gravity of second runoff (batch-sparge only)
P2 = total points in second runoff (batch-sparge only)
Ps = total points remaining in mash tun (in the liquid absorbed by the grain, or not otherwise removed from the tun) after second runoff (batch-sparge only)
Gb = gravity (points) of boiler contents after both runoffs (batch-sparge only)
Pb = total points in boiler kettle after both runoffs (batch-sparge only)
Just before recirculation and runoff, there will exist a certain water to grain ratio (mash thickness) R1 which is directly related to the total quantity of mash water used(Vm):
Vm = R1 x Wg
The gravity of the first runnings (in points per volume) is by definition the total actual points divided by the mash water volume:
G1 = Pa / Vm
The portion of the total mash water volume which is absorbed by the grain (more accurately, that which is left behind after the runoff) is
Va = Ra x Wg
For the first runoff volume V1, we will drain off all the liquid except that which is absorbed by the grain:
V1 = Vm - Va
= (R1 x Wg) - (Ra x Wg)
= (R1 - Ra) x Wg
P1 / Pa = V1 / Vm
P1 = Pa x V1 / Vm
= Pa x ((R1 - Ra) x Wg) / (R1 x Wg)
= (1 - Ra / R1) x Pa
The number of points remaining in the mashtun after the first runoff is
Pm = Pa - P1
= Pa - (1 - Ra / R1) x Pa
= (Ra / R1 ) x Pa
I
As with the first runoff, the number of points in V2 is the same as the proportion drained versus the total volume so
P2 / Pm = V2 / (V2 + Va)
P2 = Pm x Vs / (Vs + Va)
= Pm x (R2 - Ra) x Wg / ((R2 - Ra) x Wg + Ra x Wg)
= Pm x (1 - Ra / R2)
and the runoff gravity is
G2 = P2 / V2
The proportion of sugar left in the mash tun after sparging is the same proportion as the remaining (absorbed) liquid:
Ps / Pm = Ra / R2
Ps = Pm x (Ra / R2)
= Pm x (Ra / R2) x (Ra / R1)
= Pm x (Ra2 / (R1 x R2))
In the boiler, then, we now have a volume
Vb = V1 + V2
with a total number of points
Pb = P1 + P2
and therefore a gravity of
Gb = Pb / Vb
Optimizing the Batch-Sparge Process

Let's digress for a moment and see if we can optimize the extraction of sugar into the boiler for the batch-sparge case. The total number of points we put into the boiler was Pb = P1 + P2
= (1 - Ra / R1) x Pa + (1 - Ra / R2) x Pm
= (1 - Ra / R1) x Pa + (1 - Ra / R2) x (Ra / R1) x Pa
= Pa x [(1 - Ra / R1) + (1 - Ra / R2) x (Ra / R1)]
= Pa x (1 - Ra2 / (R1 x R2))
so from the above relationship,
S = Pa / Pb
= 1 / (1 - Ra2 / (R1 x R2))
Unfortunately at this point, we don't yet know the values of R1 and R2, so we can't evaluate S numerically. But we'll get there!
Let's take another look at
Pb / Pa = 1 - (Ra2 / (R1 x R2))
Since this represents the "batch-sparge efficiency", it is the expression we want to maximize. If you took calculus you might remember that to minimize or maximize a function, you must differentiate it with respect to the independent variable of interest, then set that expression equal to zero. However, we have two variables, R1 and R2. But, note that these variables are related in that we are obtaining a fixed volume of wort Vb, and therefore R2 depends on R1. Rewriting the expression for Vb in terms of R1 and R2, we see that
Vb = V1 + V2
= (R1 - Ra) x Wg + (R2 - Ra) x Wg
= (R1 + R2 - 2Ra) x Wg
Rearranging, we can write R2 in terms of R1:
R2 = (Vb / Wg) + 2Ra - R1
To maximize the batch-sparge efficiency expression, it is sufficient to maximize just the product R1 x R2. Rewriting R1 x R2 using the last equation,
R1 x R2 = R1 x ((Vb / Wg) + 2Ra - R1)
or
R1 x R2 = ((Vb / Wg) + 2Ra) x R1 - R12
We differentiate this expression with respect to R1 and set it equal to zero to maximize:
Vb/2 = Wg x (R - Ra)
Since Wg = S x Wn and S = 1 / (1 - (Ra2 / R2)),
Vb/2 = S x Wn x (R - Ra)
= Wn x (R - Ra) / (1 - (Ra2 / R2))
= Wn x (R - Ra) x R2 / (R2 - Ra2)
Rearranging,
Vb/2 x (R2 - Ra2) = Wn x (R - Ra) x R2
The difference of two squares on the left side is rewritten:
Vb/2 x (R - Ra) x (R + Ra) = Wn x (R - Ra) x R2
Dividing through by (R - Ra),
Vb/2 x (R + Ra) = Wn x R2
So
0 = Wn x R2 - Vb/2 x R - Vb/2 x Ra
= 2 x Wn x R2 - Vb x R - Vb x Ra
which is a quadratic in R with two solutions
R = (Vb +/- SQRT{Vb2 + 8 x Wn x Vb x Ra}) / (4 x Wn)
where everything inside the curly brackets after "SQRT" is considered to be under a square-root radical.
Note that the quantity under the radical is always greater than Vb. Since we need R > 0 (negative values for R don't make real-world sense!), the only root that "works" is
R = (Vb + SQRT{Vb2 + 8 x Wn x Vb x Ra}) / (4 x Wn)
This gives us all we need to design an optimum batch-sparge session.
I'm sorry, could you run that by me again, you lost me at "What you will determine is..."
 
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