1 Spirit reduction formula
1.1 Variable table
V1 = Volume of high strength spirit litres
V2 = Volume of reduced spirit litres
D1 = Density of sprit at high strength
D2 = Density of sprit at reduced strength
WR = Volume of water required for reduction litres
SI = Initial strength %
SF = Final strength %
LA = Litres of alcohol
MI + Mass of product before reduction kg
MF + Mass of product after reduction kg
1.2 Calculate Final volume of reduced spiritCalculate litres of alcohol before reduction V1 X S1
State required strength of reduced spirit= SF
Final volume V2 = V1 x S1 litres
1.3 Calculate volume of water required for reduction
Mass of product before reduction MI = V1 x D1 kg
Mass of product after reduction MF = V2 x D2 Kg
Water required WR = MF –MI litres
2 Sample calculation.
1000 litres of spirit at 90%. Requires to be reduced to 65%
Litres of alcohol is 1000 x 90 / 100 = 900 La
At 65 % Volume ( V2 ) = 900 / 65 x 100 = 1384 litres
Use spirit tables for SG.
SG at 90% and temp 15 Deg C = 0.8334
MI = 1000 x 0.8334 = 833.4 kg
M2 = 1384 x 0,9016 = 1248 kg.
Water required = M2 –M1 litres. = 1248 –833 = 415 litres.
1/ Density is taken from the “practical alcohol tables”
2/ The litres of alcohol is a constant regardless of strength.
3/ Bulk contraction takes place due to differences in spirit & water molecular size
4/ The mass of the vat contents is volume x