doobliebop
Well-Known Member
I wrote this script to calculate the optimal amount of brewing salts to add to your water profile to end up with a target profile. I grabbed most of my numbers from ProMash, and so far this seems to be working well for me.
It is a python script, so you'll need the python interpreter with numpy, and the PyIMSL numerical libraries (freely available here: http://www.imslaps.com/products/imsl/pyimsl/)
Here's a run calculating additions from my water to Burton on Trent. Plugging these numbers back into ProMash I get these exact totals.
Hope somebody finds this useful!
It is a python script, so you'll need the python interpreter with numpy, and the PyIMSL numerical libraries (freely available here: http://www.imslaps.com/products/imsl/pyimsl/)
Code:
from numpy import *
from imsl.math.linLsqLinConstraints import linLsqLinConstraints
from imsl.math.writeMatrix import writeMatrix
from imsl.math.vectorNorm import vectorNorm
#Replace the values in base_water with your water profile
base_water = [26.0, 3.6, 13.2, 28.0, 12.2, 68]
#################Values taken from ProMash################
burton_on_trent = [268., 62., 30., 638., 36., 141.]
calistoga_mineral = [11.1, 62., 30., 638., 36., 141.]
distilled_water = [0.,0.,0.,0.,0.,0.]
dortmund = [260.,23.,69.,240.,206.,270.]
dublin = [118., 4., 12., 54., 19., 319.]
edinburgh = [140., 36., 92., 231., 60., 270.]
london = [90., 4., 24., 58., 18., 123.]
marin_county_ca = [12., 10., 15., 17., 13., 74.]
munich = [76., 18., 1., 10., 2., 152.]
pilsen = [7., 3., 3.2, 5.8, 5., 9.]
vienna = [200., 60., 8., 125., 12., 120.]
yorkshire = [105., 17., 23., 66., 30., 153.]
###########################################################
target = burton_on_trent
#Salt contents (PPM / (grams per gallon))
caso4 = [61.5, 0.0, 0.0, 147.4, 0.0, 0.0]
mgso4 = [0.0, 26.1, 0.0, 103.0, 0.0, 0.0]
nacl = [0.0, 0.0, 103.9, 0.0, 160.3, 0.0]
nahco3 = [0.0, 0.0, 72.0, 0.0, 0.0, 189.0]
cacl2 = [72.0, 0.0, 0.0, 0.0, 127.4, 0.0]
caco3 = [105.8, 0.0, 0.0, 0.0, 0.0, 158.4]
# The overall goal here is to find x ST:
# Ax =~ b
# x >= 0
a = transpose([caso4, mgso4, nacl, nahco3, cacl2, caco3])
b = array(target) - array(base_water)
xlb = [0.] * 6
xub = [-1.0e30] * 6
c = []
con_type = []
bu = []
bl = []
residual = []
x = linLsqLinConstraints(a, b, c, bl, bu, con_type, xlb, xub, residual=residual)
ion_labels = ['', 'Ca', 'Mg', 'Na', 'SO4', 'Cl', 'HCO3']
salt_labels = ['', 'CaSO4', 'MgSO4', 'NaCl', 'NaHCO3', 'CaCl2', 'CaCO3']
writeMatrix("Salt amounts to add \n(Grams per Gallon)", x, colLabels=salt_labels)
writeMatrix("Target Profile \n(PPM)", target, colLabels=ion_labels)
writeMatrix("Base Water + Recomended Salt Additions \n(PPM)", dot(a,x) + array(base_water), colLabels=ion_labels)
writeMatrix("Residuals \n(PPM)", residual, colLabels=ion_labels)
print ("\nNorm of residual = %f" % (vectorNorm(residual)))
Here's a run calculating additions from my water to Burton on Trent. Plugging these numbers back into ProMash I get these exact totals.
Code:
ryan@ubuntu-desktop:~/Desktop$ python water.py
Salt amounts to add
(Grams per Gallon)
CaSO4 MgSO4 NaCl NaHCO3 CaCl2 CaCO3
2.888 1.817 0.106 0.000 0.083 0.489
Target Profile
(PPM)
Ca Mg Na SO4 Cl HCO3
268 62 30 638 36 141
Base Water + Recomended Salt Additions
(PPM)
Ca Mg Na SO4 Cl HCO3
261.3 51.0 24.2 640.8 39.8 145.5
Residuals
(PPM)
Ca Mg Na SO4 Cl HCO3
-6.67 -10.98 -5.81 2.78 3.77 4.45
Norm of residual = 15.513117
Hope somebody finds this useful!