[Kaiser]

Here is something I had been working on a while back but wanted to make sure its outcome matches what I'm seeing in my brewing:

batch_sparge_simulator.xls

It's a spread sheet that allows you to simulate an up to 3 run-off batch sparge (which includes no-sparge) and party gyle brewing. While it may look complex here is what you enter:

* E5-E8 gets your unit preferences.
* E11-E15 gets info about the 1st mash. grain weight, extract potential and anticipated conversion efficiency.
* E18-E19 gets info about the apparent grain absorption. Use 0.12 gal/lb or 1.3 l/kg if you don't know it. The efficiency calculator i have can calculate it for you if you supply enough data

In E22 you find the possible volume and gravity you can drain from the mash. It assumes that you would collect this volume but you can change this in E25. The section on the right shows you what you could make from that if you boil it down. 10-15% is a realistic boil-off but you can push it higher if you need to.

If you do a 2nd run-off enter the amount of water you add into E29. If you add grain, you can specify this in E30. The spreadsheet assumes it has the extract potential of the initial grist.

Then it calculates for you how much more wort can be drained and what the expected gravity is. Again, you can specify how much you collect. Note that all these volumes are temperature corrected. If you use a measurement that you took on brew day you need to correct it for temperature.

Now there are a number of permutations on the combination of run-offs:

* 1st and 2nd (typical 2 run-off batch sparge)
* 1st, 2nd and 3rd (typical 3 run-off batch sparge)
* just 2nd
* just 3rd
* 2nd and 3rd

For all of these it lists the efficiency and what volume/strength you should expect from them.

I hope this helps. I still plan to do a party gyle at some point but have no idea when I will do that. It also worked well for calculating the efficiency of partially drained batch sparges. This means you don't let the grain run dry by collecting less than you could. It happened to me when I got my Weissbier lauter stuck halfway through the 1st run-off. I just added more water and made it a 3-runoff batch sparge.

Let me know if the results don't match your brewing observations. The theory behind this spreadsheet is the same I used for my efficiency troubleshooting work and the batch sparging analysis.

Kai

[bmilford]

Cool, thanks.

[akr71]

Many thanks!

[chezteth]

This is great!  I just did my first partigyle brew a few weeks ago.  I used the chart in Randy Mosher's book "Brewers Companion".  It worked very well to get me started on doing a partigyle.  Now I can play around with the numbers to see what would happen if I did...   Thanks for creating such a great tool!!

Happy Brewing,
Brandon

[Kaiser]

FYI, I added some documentation for this spreadsheet:

http://braukaiser.com/wiki/index.php/Batch_Sparge_and_Party_Gyle_Simulator

Kai

[stout_fan]

Way to Kai,
this will come in handy!

[stadelman]

Thats cool... Thanks Kai!

[bonjour]

Kai

check the display of SG,  for a 28 lb with 1 qt/pound ratio I get 1113.9

A decimal misplacement  (1.114)
 
Otherwise nice

[Kaiser]

Kai

check the display of SG,  for a 28 lb with 1 qt/pound ratio I get 1113.9

A decimal misplacement  (1.114)
 
 

I think this is intended. In the past I have made the distinction between SG which has the form 1XXX.y and sg which has the form 1.XXXy. I think both notations are used in brewing. The 1XXXy shows up in Brigg’s Brewing and Malting science book.

You guys should be using Plato anyway

Kai

[bluesman]

Super work once again Kai. Thanks!

How are you measuring your collections and are you assuming some evaporation?

[Kaiser]

How are you measuring your collections and are you assuming some evaporation?

All volumes are given as temperature corrected volumes. Evaporation is not expected during mash or sparge but there is a boil-off calculation on the side of each collected and combined wort volume.

Kai

[tommeier]

Good work Kai, I will give this spreadsheet a whirl sometime.  Right off, I'm not understanding the three different % inputs for extract potential, conversion eff., and run-off efficiency, but I'll get there.

I can input a mash thickness of 1 qt/lb, and get a very wide range of SG on the first runnings simply by changing the "conversion efficiency".  But shouldn't this be a function only of qt/lb strike water and dead space?  Because the overall efficiency will depend on how much wort is collected, but the first runnings will have a SG corresponding to the thickness of the mash only, and volume losses based on absorption and dead space loss.

For example at 1 qt/lb mash thickness I would expect the first runnings to be ~1.100 SG.  Using a typical 70% efficiency with the spreadsheet I get 1.085 SG.

Appreciate your thoughts on that.   


re: parti-gyle brewing:
Parti-gyle brewers usually find that some back-mixing is needed to get the proper gravity.  The % of the 'gravity points' in the first runnings is not an exact science.  A good guess is 60% to 70% of the sugars go into the first runnings when you collect equal volumes in the 1st and 2nd runnings.

some additional info:
http://www.antiochsudsuckers.com/tom/parti-gyle.htm

A simple spreadsheet for parti-gyle brewing:
http://www.sonic.net/~ctweney/parti_gyle.htm

[Kaiser]

Good work Kai, I will give this spreadsheet a whirl sometime.  Right off, I'm not understanding the three different % inputs for extract potential, conversion eff., and run-off efficiency, but I'll get there.

Extract potential is the average extract potential of the grist. Usually between 80 and 82%. Keep the moisture content at 4%. That also affects that extract potential since the 80-82% number is reported for completely dry grain.

Conversion efficiency measures how well you expect the mash to convert. Here is some info http://braukaiser.com/wiki/index.php/Understanding_Efficiency#Conversion_efficiency. If you expect to convert 100% of the starches, enter 100%. I found that though many brewers assume that all the starches convert it is not necessarily a given. This will also answer your question about the 1.100 vs. 1.085  first wort SG.

At 100% conversion a 1 qt/lb mash should give you a first wort gravity of about 1.110. There is a table at the aforementioned link that shows that.

The run-off efficiency is more like the efficiency you know and calculate. It is the efficiency into the kettle for this particular run-off or combination of run-offs.

Thanks for the link to the other spreadsheet.  I glanced it over and it is different from what I came up with in that my spreadsheet focuses only on predicting the gravities and volumes of the run-offs based on a few starting parameters. The spreadsheet you linked to does not predict how much wort you can run off the mash, for example.

Kai