Question 5 In a casein plant the entering coagulum containing casein and lactose is passed?
... through two cookers and acidified to remove the casein. The curd is removed from the whey by screening and then washed and dried. The casein fi
... through two cookers and acidified to remove the casein. The curd is removed from the whey by screening and then washed and dried. The casein fines are removed from the whey and the wash water by hydrocyclones and mixed with the heated coagulum just before the screen. The whey is used for heating the first cooker and steam for the second by indirect methods. Some of the more accessible streams have been sampled and analysed for casein and lactose; the remainder of the steam can be assumed to be water without significantly effecting the results. In addition the moisture content of the final dried product has been determined.
% Composition on a weight bases
CaseinLactoseMoisture
Coagulum2.763.68
Whey (raw)0.0124.1
Whey (cyclone)0.0074.1
Wash water0.0260.8
Waste wash water0.0080.8
Dried product11.9
From this data calculate a complete mass balance for the process using simple step by step approach, starting with the hydrocylones. Assume that the lactose is completely soluble in all streams and concentrations are the same.
a.Draw up and fill in the following table (27 marks)
Mass Flow Kgh-1
CaseinLactoseTotal
Coagulum + Fines mixed
Mixed fines
Dewheyed curd
Raw whey
Whey fines stream
Waste wash water
Wash water fines
Pressed curd
Dried Product
b.What % of the casein going into the screen is recovered fines? (3 marks)
c.What % recovery efficiencies do the two sets of hydro-cyclones display? (3 marks)
d.What are the % compositions of the pressed curd and the dried product? (3 marks)
or:... through two cookers and acidified to remove the casein. The curd is removed from the whey by screening and then washed and dried. The casein fines are removed from the whey and the wash water by hydrocyclones and mixed with the heated coagulum just before the screen. The whey is used for heating the first cooker and steam for the second by indirect methods. Some of the more accessible streams have been sampled and analysed for casein and lactose; the remainder of the steam can be assumed to be water without significantly effecting the results. In addition the moisture content of the final dried product has been determined.\t% Composition on a weight bases\tCasein\tLactose\tMoistureCoagulum\t2.76\t3.68\tWhey (raw)\t0.012\t4.1\tWhey (cyclone)\t0.007\t4.1\tWash water\t0.026\t0.8\tWaste wash water\t0.008\t0.8\tDried product\t\t\t11.9From this data calculate a complete mass balance for the process using simple step by step approach, starting with the hydrocylones. Assume that the lactose is completely soluble in all streams and concentrations are the same.a.\tDraw up and fill in the following table (27 marks)\tMass Flow Kgh-1\tCasein\tLactose\tTotalCoagulum + Fines mixed\t\t\tMixed fines\t\t\tDewheyed curd\t\t\tRaw whey\t\t\tWhey fines stream\t\t\tWaste wash water\t\t\tWash water fines\t\t\tPressed curd\t\t\tDried Product\t\t\tb.\tWhat % of the casein going into the screen is recovered fines? (3 marks)c.\tWhat % recovery efficiencies do the two sets of hydro-cyclones display? (3 marks)d.\tWhat are the % compositions of the pressed curd and the dried product? (3 marks)
