Mass Balance
Nur Istianah, ST.,MT.,M.Eng
28/04/2017
Basic concept
Conservation Law
out
in m
m
Mass Balance determination
Steps
• Drwaing proses diagram
Consist a square as a system and followed by arrow for each stream
• Put the amount of each stream (kg)
Unknown variabel noticed by a letter
• Make an equation
Based on conservation Law
• Solving the equation
28/04/2017
Example 1
An dairy industry produce 100 kg of low fat cream (18 % fat, 82% water, w/w) which the ingredients are double cream (48 % fat, 52% water, w/w) and milk(3.5 % fat,
96.5% water, w/w). Calculate the amount of double cream and milk needed!
Solution:
Mixer Cream, 48% fat
Milk, 3.5% fat
Low fat cream 18% fat
100 kg
Define double cream = y kg and milk= x kg Overall mass balance:
y + x = 100 kg ………. Eq.1
Fat mass balance:
0.035x + 0.48y = 100(0.18) ………. Eq.2
Eq. 1 dan 2 : 0.035(100-y) + 0.48y = 18 3.5 - 0.035y + 0.48y = 18
y = 32.58 kg Thus ………. X = 67.42 kg
28/04/2017
Example 2
Determine the proportion of beaf (23 % fat ) and chicked (5
% fat) used to produce a meat product which contain 15 % of fat.
Solution:
Mixer Chicken, 5% fat
Beaf, 23% fat
Meat product 15% fat
Define beaf= A kg, chicken = B kg and meat product= C kg Overall mass balance:
A + B = C ………. Eq.1
Fat mass balance:
0.23A + 0.05B = 0.15C ………. Eq.2
Eq. 1 dan 2 : 0.15A + 0.15B = 0.15C 0.23A + 0.05B = 0.15C A/ B = 10/8 = 5/4
28/04/2017
Excercise 1
Determine the amount of NaCl 10 % produced by the dillution of 15 kg NaCl 20 % using pure water!
Excercise 2
How many percent the decreasing of fruit weight that was dried from 80 % to the 50 % moisture content!
28/04/2017
Excercise 3
The 100 kg of rice that has 19 % moisture was dried until 10 % moisture. Calculate the yield of drying process and
also find the amount of water loosed!
Excercise 4
Fresh milk that contained 90 % water , 5 % fat, 3 % protein and another component 2 %, was processed in spray dryer to produce milk powder with moisture 10%.
Calculate the yield of dryer!
THANKS FOR YOUR ATTENTION
The best person is one give something useful always
28/04/2017
