What's the sparge to strike water ratio?

[RoatanBill]

I know there is no one answer to my question, but there must be some reasonable range of ratios. What are they?

What follows is for an all electric HERMS system.

The reason I ask the question is because I've broken the HLT's job down to three functions - Produce the initial strike water, provide heat for the HERMS coil and provide sparge water.

Well, the BK can produce the strike water as it's just sitting there doing nothing. If the ratio of sparge to strike water is reasonably low, then a small kettle only large enough for sparge water would suffice.

Now here's the twist. I've never considered putting the HERMS coil inside the HLT. I want it outside as a standalone heat exchanger. If the sparge to strike water ratio is near what I think it is then it can get it's heat from a mini HLT. The external heat exchanger can then be repurposed to cool the wort from the BK.

 

[doug293cz]

I know there is no one answer to my question, but there must be some reasonable range of ratios. What are they?

What follows is for an all electric HERMS system.

The reason I ask the question is because I've broken the HLT's job down to three functions - Produce the initial strike water, provide heat for the HERMS coil and provide sparge water.

Well, the BK can produce the strike water as it's just sitting there doing nothing. If the ratio of sparge to strike water is reasonably low, then a small kettle only large enough for sparge water would suffice.

Now here's the twist. I've never considered putting the HERMS coil inside the HLT. I want it outside as a standalone heat exchanger. If the sparge to strike water ratio is near what I think it is then it can get it's heat from a mini HLT. The external heat exchanger can then be repurposed to cool the wort from the BK.

You going to batch sparge or fly sparge? The answer to your question is different based on how you sparge.

Brew on

 

[Yooper]

I
Now here's the twist. I've never considered putting the HERMS coil inside the HLT. I want it outside as a standalone heat exchanger. If the sparge to strike water ratio is near what I think it is then it can get it's heat from a mini HLT. The external heat exchanger can then be repurposed to cool the wort from the BK.

Well, you can definitely do a standalone HEX. However, you may be better off with a RIMS then.

Remember that it takes a ton of ice to chill the wort from boiling to pitching temperatures, if that is your plan. I tried it once with my HERMS- put ice in the HLT where the coil is and recirculated to chill.

It took a bit over 42 pounds of ice to chill 5 gallons of wort to 75 degrees. I did it once. Just once- it was a huge pain to make that much ice out of non-chlorinated RO water and store it in the freezer and then haul it to my HLT.

If you want a standalone HEX, a RIMS would be much easier to use.

As far as how much water to use and the ratio, well there isn't one.

Use 1-2 quarts of water per pound of grain in the mash (generally, 1.5 quarts/pound is good before it's neither too thick to stir nor too thin) and sparge up to your boil volume.

so, say you're doing a 15 gallon sized batch and have 30 pounds of grain. You'd mash in with 45 quarts of water (11.25 gallons, or 11 gallons if you like nice even numbers).

The grain will absorb about .125 gallon/pound, so you'd lose 3.75 gallons to absorption. If your boil volume is 17 gallons (1.5 gallons per hour boil off + .5 gallon lost to chiller/trub), you'd need 9.75 gallons of sparge water.

Check my math, please. I'm enjoying a beer after a long day of chores, and just did that super quick.

 

[doug293cz]

...

so, say you're doing a 15 gallon sized batch and have 30 pounds of grain. You'd mash in with 45 quarts of water (11.25 gallons, or 11 gallons if you like nice even numbers).

The grain will absorb about .125 gallon/pound, so you'd lose 3.75 gallons to absorption. If your boil volume is 17 gallons (1.5 gallons per hour boil off + .5 gallon lost to chiller/trub), you'd need 9.75 gallons of sparge water.

Check my math, please. I'm enjoying a beer after a long day of chores, and just did that super quick.

Well, you asked, so I'll check your math. For 17 gal pre-boil and 3.75 gal of grain absorption, you need 20.75 gal of total brewing water. 11.25 gal of strike water plus 9.75 gal of sparge water totals 21 gal. So, there is a 1 qt discrepancy. Probably within measurement error if you drink beer when you measure as well as when you calculate.

That said a quart one way or the other in a 15 gal batch would have a minimal effect on outcome.

Brew on

 

[Dcpcooks]

At 1.3 quarts per pound your pretty close to 50/50 strike to sparge water. At 1.5 your closer to 55 /45 strike to sparge water. So you will want to consider that you'll need roughly 1/2 of your brewing liquor available in the HLT. As you increase your strike volume you can expect to see some loss of efficiency.

Blichmann makes a k-rims system called the brew easy. It's a two vessel system where all of your brewing liquor is added all at once split between two kettles. The bottom kettle heats the liquor and uses either gas or electric to maintain your mash temp. All of the wort is recirculated through the grain bed during the mash. This results in a very thin mash. The thin mash creates some challenges for the brewer, water profiles and ph become more important to the process and impact mash efficiency. The brew easy often has a substantially lower efficiency than a traditional set ups. I see people post of efficiencies in the mid to low 50% range compared to 70-78% efficiencies in three vessel systems. It is a small compact footprint and is repeatable by design. So you can learn to live with the systems constraints. From what I've read and some summations on my part I believe mash ph is a large culprit in the reduced efficiency but I could be wrong on that. I've never really had to solve the problem as I decided not to purchase that system. That is mostly due to my desired batch size and my desire to make higher gravity beers. Those goals didn't jive well with the set up. I point this out to illustrate some of the challenges of a thin mash for you to consider. You can search for more info if desired.

I agree with Yooper the a rims is a better option for you to research. You can apply heat through an element and run a very stable system the can ramp mash temps quickly and hold temps quite simply. Many will say they are more efficient than a herms coil. I won't get into that discussion.

Cooling your wort should be a separate consideration in my opinion. If I remember correctly your in the islands and would likely have high ground water temps. That may require you to use a two stage chilling set up where you need to chill your ground water before you can use it to bring your wort to pitching temps. You could also build a fermentation control system that will allow you to lower your wort below ground water temps to pitching temps. My point here is, as yooper pointed out, ice is a pain in the butt to deal with as a cooling method. So your idea of an external coil to manage cooling and heating may be a challenge to build efficiently.

 

[RoatanBill]

I'm planning on fly sparging, but who knows - I may try batch too.

I have access to ridiculous amounts of refrigeration / ice. I just counted up the commercial refrigerators and freezers and it comes to 9 units. I'm also planning on having a dedicated unit for fermentation refrigeration that may or may not be glycol based to push temperatures way down. I can tap that also.

I don't like the RIMS system because it pushes the product past a very hot heating element in close confinement. I prefer the HERMS approach which pushes product past a much lower more gentle heat source. My chemistry classes shape my preference. I'll admit the BK also pushes product past the element, but that is unavoidable unless I want to implement a steam system which is a bit much and propane under the BK is absolutely out of the question.

Your ratios come close to 50/50. I wasn't expecting it to be so high for the sparge. One of these days I'm going to have to spend some time trying to understand some of the recipes. I tried it once on this site and got totally lost in the jargon; that's why I asked what to you is obviously a simple question. I couldn't figure it out. I read Palmer's "How To Brew" but it covers the brew topic at about a 10,000 ft altitude. I want something quite a bit more detailed near sea level.

I've looked everywhere for a pure SS counterflow chiller and came up empty. The one I saw from China had such lousy welds I wouldn't consider it. With the weld porosity on display I doubt they used backup Argon when they made their welds. Since the interior of the plumbing is hidden from the purchaser, they can cheat resulting in "sugaring" the interior and that's no way to TIG SS.

I've got an SS chiller drawn up, not counterflow but close, but lack some of the rather expensive tooling (slip roll) to build it. I'm deciding how to proceed and this query was part of that process.

Thank You

 

[doug293cz]

At 1.3 quarts per pound your pretty close to 50/50 strike to sparge water. At 1.5 your closer to 55 /45 strike to sparge water. So you will want to consider that you'll need roughly 1/2 of your brewing liquor available in the HLT. As you increase your strike volume you can expect to see some loss of efficiency.

...

Not necessarily. Kai Troester has shown that maximum lauter efficiency with a single batch sparge is achieved when first runnings volume is equal to sparge runnings volume. To get equal runnings volume, strike water volume must necessarily be more than the sparge volume due to grain absorption (which only affects first runnings.) Kai also shows that the response curve is quite flat on either side of the maximum, such there is an insignificant change in efficiency for ratios of first runnings to sparge runnings volumes between 60:40 and 40:60. Thus you don't have to be exact with your ratio.

With respect to mash thickness, Kai showed that thinner mashes convert at a faster rate than thicker mashes. This can help get more complete conversion in cases where mash times are marginal as far as getting 100% conversion.

The net result is that you would usually get better mash efficiency (conversion efficiency times lauter efficiency) with mash thickness upwards of 1.5 qt/gal. For a 5 gal batch with an 8 lb grain bill "optimal" mash thickness is a little over 2.1 qt/lb, but for a 15 lb grain bill, it drops to a little below 1.4 qt/lb. (This will differ slightly for different levels of boil off, MLT dead space, grain absorption rate, etc.)

Brew on

 

[doug293cz]

I'm planning on fly sparging, but who knows - I may try batch too.

...

When fly sparging, your HLT needs to be able to hold almost your full pre-boil volume, This is because you leave close to your strike water volume in your MLT at the end of the sparge. The difference in volume is the amount you run off before starting the sparge water flow.

Brew on

 

[pricelessbrewing]

One day I'm just going to make a script to go through and like all your posts doug.

 

[schematix]

When fly sparging, your HLT needs to be able to hold almost your full pre-boil volume, This is because you leave close to your strike water volume in your MLT at the end of the sparge. The difference in volume is the amount you run off before starting the sparge water flow.

Brew on

I guess that's one way to do it, but seems wasteful. My MLT is nearly dry (and much lighter!) when my lauter is done. I cut the sparge water once i have enough in the BK and MLT to get my pre boil volume, accounting for grain absorption and piping losses.

 

[RoatanBill]

doug293cz: Thanks for the two references. I'll read them in the morning.

When fly sparging, your HLT needs to be able to hold almost your full pre-boil volume, This is because you leave close to your strike water volume in your MLT at the end of the sparge. The difference in volume is the amount you run off before starting the sparge water flow.

Brew on

I read this at least 6 times and don't quite get it. Can you give me an example with numbers please?

 

[doug293cz]

I guess that's one way to do it, but seems wasteful. My MLT is nearly dry (and much lighter!) when my lauter is done. I cut the sparge water once i have enough in the BK and MLT to get my pre boil volume, accounting for grain absorption and piping losses.

I would consider your method a modified fly sparge. I've often wondered why more brewers don't do it your way. I suspect there would be a small loss of efficiency with your method, but since fly sparging is damn near impossible to model accurately, I would never be able to prove it or quantify it.

Brew on

 

[doug293cz]

doug293cz: Thanks for the two references. I'll read them in the morning.

I read this at least 6 times and don't quite get it. Can you give me an example with numbers please?

I don't have any numbers handy, as I don't fly sparge, nor do any fly sparging calculations. But, let me try to explain it better...

The normal fly sparge lautering process is to vorlauf (recirculate) wort from the bottom of the MLT to the top of the mash. This clarifies the wort, and sets the grain bed. There will normally be several inches of just wort on top of the grain bed. Recommended practice when lautering is to drain the MLT until there are only 1 or 2 inches of wort above the grain bed. Let's call the volume you drain to get to 1 - 2 inches "V1." Once you've pre-drained some of the wort, you start sprinkling sparge water on top of the grain bed, while simultaneously draining wort at the same rate as you add sparge water. This keeps the water level at 1 - 2 inches above the grain bed for the duration of the sparge. The amount of sparge water you need is equal to your pre-boil volume minus V1, because that's the additional amount of water that must be added to the MLT to get your full pre-boil volume in your BK. The grain is left saturated and covered with 1 - 2 inches of water when you are done.

Note that this "standard" fly sparge process is different than what @schematix describes in his post above.

Brew on

 

[MaryB]

I do 48%:52% mash(1.5qt per pound) to sparge for my house ale and most other beers. There are exceptions to the rule like high gravity beers with huge grain bills. My house ale runs 5.5% ABV so it is middle of the road. IPA I like runs in the same area(6%ish). The Belgian strong I am working on will be a lot higher and I will have to tweak water volumes.

 

[RoatanBill]

doug293cz:

I read those two references and understood about 10% of the content. It's the jargon and definitions that evade me. I'm an engineer, so graphs and numbers are like oxygen to me, but the use of terms unknown to me renders the content a mystery. I thought Plato was an ancient philosopher, for example. Googling doesn't help much.

While reading, I got the distinct impression that beer must be like the loaves and fishes of yore. There's no sparge, 1 sparge, 2 sparge, ... and it's all good. I don't get it. How can you dilute the first running not just once but multiple times and call the resultant beer. I think that would be more like Coors or Miller lite - goat pee, non beer.

 

[Yooper]

Think of your mash tun as a washing machine.

The mash is the washing cycle. You want to extract the sugars (the dirt) out of the grain (laundry).

Then you want to rinse out the sugars (dirt).

My washing machine has an optional second rinse cycle, and it would be useful for exceptionally dirty or soapy clothes. Each time you rinse, you would probably get a little more dirty water (sugar) out, but comes with diminishing returns- you'd get out more clean water than dirty water with each successive rinse.

Same with sparging. You can actually take a reading and get the level of sugars you're still extracting over time. Most of us stop when the wort reads 1.015 or so I'd guess, but you could go to 1.010 to maximize the efficiency without a poor flavor impact. Then you boil longer to reduce the volume. This maximizes efficiency, the amount of sugar you get from the grain, as it 'rinses' every bit of sugar you can get out of it. But it's not efficient from a time/fuel standpoint. So that's where the diminishing returns comes in.

I really suggest getting a bucket and a pot, and just brewing a small batch. Trust me, it's the only way to get a working knowledge of the process. You can make fantastic beer with a bucket, a bag, and a pot. It's a cheap way to see how it works, and avoid a very costly mistake. You aren't going to know what equipment you really need until you have a clear picture of the process.

Just brew once. Then almost all of this will make sense.

 

[doug293cz]

doug293cz:

I read those two references and understood about 10% of the content. It's the jargon and definitions that evade me. I'm an engineer, so graphs and numbers are like oxygen to me, but the use of terms unknown to me renders the content a mystery. I thought Plato was an ancient philosopher, for example. Googling doesn't help much.

While reading, I got the distinct impression that beer must be like the loaves and fishes of yore. There's no sparge, 1 sparge, 2 sparge, ... and it's all good. I don't get it. How can you dilute the first running not just once but multiple times and call the resultant beer. I think that would be more like Coors or Miller lite - goat pee, non beer.

Every field has its own set of terms, which must be learned in order to converse with others in the know. Brewing is no different. A good place to start your learning is http://www.howtobrew.com/ written by John Palmer. Early in the book there is a glossary, which will help with all the new vocabulary.

Plato is just another way of measuring the sugar concentration of wort. Plato is measured with a hydrometer, just like specific gravity, but the scale units are different. SG is more common with homebrewers, and Plato more common with professionals. Plato is defined as the weight percent sugar in the wort. So a wort that is 10˚ Plato is 10% sugar by weight and the balance (90%) of the weight is water. Turns out the SG scale and Plato scales are almost linearly related, with SG ~= 1 + 4 * Plato / 1000 (or multiply by Plato by 4 to get the last 2 digits of SG.)

When batch sparging (rinsing residual sugar out of the grain) you use roughly the same total amount of water as you would for a no sparge batch. If you are doing a no-sparge process, all of you water goes into the mash. If doing a single batch sparge, roughly half your total water goes into the mash, and the other half is used for the sparge. If doing 2 batch sparge steps then the total water is divided in three. The first amount is used for mashing, the second for the first sparge step, and the third for the second sparge step. This way, more sparges doesn't mean more pre-boil volume, or more dilute wort. With sparging, the pre-boil SG is higher for the same pre-boil volume than the SG for no-sparge.

Brew on

 

[RoatanBill]

Yooper:

The part I was missing was to evaporate large quantities of water to concentrate the wort. Thank You. You consistently come to my aid.

My wife, the baker, says making bread is chemistry. Since beer is liquid bread then brewing must be chemistry, and chemistry says there are optimal amounts of energy input to many systems. My wife's NY Cheesecake gets baked at 4 different temperatures, for example.

Boil time can't be arbitrary to produce the best product. I can't, for example, add 1 egg to a gallon of water and boil it till there's only a pint left to produce a decent hard boiled egg.

I suppose that's where the art come into play; a balance dictated by experience.

I'll have some test equipment and grains by the end of June when my wife will bring them back from Florida. In the interim I have to produce a fermentation chamber for post boil as ambient daylight temps will be 95 by then. People here acclimate to the heat so that when temps hit 70, rarely, people are wearing coats - I kid you not. Personally, A/C at 80 is real nice, but still not optimal for beer, and I do want optimal.

doug293cz:

I've read "How To Brew" several times and pick up something new each pass. I've got a few books in my Amazon cart, but they are just what struck me as interesting. I have no idea what I'll actually get information wise. As an engineer, I recognize that I don't function well on limited information. I'm also well acquainted with "analysis paralysis" which keeps me digging for more.

Your description of how water is used in the mash/lauter process makes sense. Kettle size, the grain bill and what's reasonable to avoid a stuck mash/sparge determines the limits of what can be considered.

I appreciate your clear and thorough explanation.

 

[Dcpcooks]

Not necessarily. Kai Troester has shown that maximum lauter efficiency with a single batch sparge is achieved when first runnings volume is equal to sparge runnings volume. To get equal runnings volume, strike water volume must necessarily be more than the sparge volume due to grain absorption (which only affects first runnings.) Kai also shows that the response curve is quite flat on either side of the maximum, such there is an insignificant change in efficiency for ratios of first runnings to sparge runnings volumes between 60:40 and 40:60. Thus you don't have to be exact with your ratio.



With respect to mash thickness, Kai showed that thinner mashes convert at a faster rate than thicker mashes. This can help get more complete conversion in cases where mash times are marginal as far as getting 100% conversion.



The net result is that you would usually get better mash efficiency (conversion efficiency times lauter efficiency) with mash thickness upwards of 1.5 qt/gal. For a 5 gal batch with an 8 lb grain bill "optimal" mash thickness is a little over 2.1 qt/lb, but for a 15 lb grain bill, it drops to a little below 1.4 qt/lb. (This will differ slightly for different levels of boil off, MLT dead space, grain absorption rate, etc.)



Brew on

I see RoatanBill trying to solve for problems he doesn't yet understand. My concern was that he was looking to do large strike volumes and very small sparge volumes. So I wanted to point out some of the process flow and pit falls associated with his ideas.

I see efficiency as a potential challenge in his instance since he will be bringing grain and equipment to an island. I'm usually not a proponent of driving efficiency for new brewers but in this case I see it as a concern. I've also seen several of his posts and I know he's going to engineer all of the process. So build once cry once may hold more value for him.

 

[RoatanBill]

I see RoatanBill trying to solve for problems he doesn't yet understand. My concern was that he was looking to do large strike volumes and very small sparge volumes. So I wanted to point out some of the process flow and pit falls associated with his ideas.

You hit that nail right on the head. I want to know why things are done and what the benefits are versus another method. I assumed that strike water was maybe 20% of the liquid total. Now I see I was way off now that i KNOW better, thanks to you folks.

I see efficiency as a potential challenge in his instance since he will be bringing grain and equipment to an island. I'm usually not a proponent of driving efficiency for new brewers but in this case I see it as a concern. I've also seen several of his posts and I know he's going to engineer all of the process. So build once cry once may hold more value for him.

Right again. I have to deal with customs, lawyers, customs brokers, inspectors, shippers, insurance agents, ... the list is long. I need to bring as much in on one trip as possible because the overhead these people represent is huge. If I do everything as best I can I'll get away with paying only a 50% markup from what it costs in the US. Definitely buy once cry once, but that's been my life long habit anyway.