Formulas to Find Juice Heater and Evaporator vapour Line Dia
In Equipment Design Drawings of the Sugar Process Industry, vapour line dia is one of the important Calculations. This article provided formulas for calculating vapour line dia for juice heaters and evaporators and an online calculator.
Juice Heater Vapour Inlet Line Dia:
Required Data For Calculation:
1. Crushing Rate in TCH
2. Juice Percentage ( P) ( Like Mixed juice % cane , Sulphited juice% Cane, Clear juice% cane)
3. Specific heat of juice in Kcal/kg/^{o}C ( Cp )
The following equation gives the specific heat of sucrose solutions:
Cp = 1 – 0.006 B
B = brix of the solution. ( This equation is a close approximation)
This formula may be applied without serious error to juices, syrups, and molasses of different purities.)
a) Juice inlet temperature ( Ti ) in ^{o}C
b) Juice outlet temperature ( To ) in ^{o}C
c) Juice heater inlet vapour Temperature ( Tv) in oC
d) Juice Heater inlet vapour velocity ( V ) in m/sec
e) Latent heat vapour of inlet vapour ( λ ) in Kcal/ kg (Taken from the steam table)
f) Specific Volume of inlet Vapour (Sp) in M^{3}/kg (Taken from steam table)
The formula for Calculation:
Heat received by juice = Heat rejected by vapour
Qj x Cp x ΔT = W x λ
Qj = Quantity of the juice in kg/hr (TCH x P x 1000/100)
ΔT = To – Ti
W = Required vapour quantity for juice heating getting in kg/hr after that it is to be converted into M^{3}/sec by multiplying the specific volume of vapour
( Note: For equipment flexibility purposes it is better to consider 10% extra vapour on actual requirement )
I.e [ Qw = (W x Sp x 1.1) /3600]
Dia of vapour Line = SQRT [ Qw / (0.785 x Velocity of vapour) ]
Hint: The general formula to find the area of vapour pipeline is Q = A V & Area (A) = 0.785 x D^{2}
Evaporator Body Vapour Inlet and Out Line Dia:
Required Data For Calculation:
a) Evaporator Body Heating Surface ( H ) in m^{2}
b) Evaporation Rate of the body ( E ) in Kg/ hr/ m^{2 }( To take maximum value for calculating the vapour lines)
c) Temperature of evaporator body Inlet vapour ( Ti ) in ^{o}C
d) Temperature of evaporator body outlet vapour (To ) in ^{o}C
f) Velocity of evaporator body inlet vapour (V i) in m/sec
g) Velocity of evaporator body outlet vapour (V o) in m/sec
Evaporator Bodies Vapour Velocities Recommended by E.Hugot
Triple in m/sec | Quadruple in m/sec | Quintuple in m/sec | ||||
Min | Max | Min | Max | Min | Max | |
Exhaust steam to 1st effect | 25 | 30 | 25 | 30 | 25 | 30 |
Vapour from 1st effect | 30 | 35 | 30 | 35 | 30 | 35 |
Vapour from 2nd effect | 40 | 45 | 35 | 40 | 30 | 35 |
Vapour from 3rd effect | 50 | 60 | 40 | 45 | 35 | 40 |
Vapour from 4th effect | 50 | 60 | 40 | 45 | ||
Vapour from 5th effect | 50 | 60 |
As Per E.Hugot Apparent Heat Transfer Coefficients for Evaporator Bodies
Kcal/m^{2}/^{o}C/hr | ||||||
Triple Effect | Quadruple Effect | Quintuple Effect | ||||
Min | Max | Min | Max | Min | Max | |
1st effect | 2000 | 2500 | 2000 | 2400 | 2000 | 2400 |
2nd effect | 1500 | 1800 | 1400 | 1800 | 1400 | 1800 |
3rd effect | 800 | 1000 | 1000 | 1400 | 1300 | 1500 |
4th effect | 600 | 800 | 800 | 1000 | ||
5th effect | 500 | 600 |
E.Hugot recommended the Evaporation Rate of The Several Vessels of a multiple effect working under the condition of temperature drop from 120^{o}C to 55^{o}C
Triple Effect | Quadruple Effect | Quintuple Effect | ||||
Kg/m^{2}/hr | Lb/Ft^{2}/hr | Kg/m^{2}/hr | Lb/Ft^{2}/hr | Kg/m^{2}/hr | Lb/Ft^{2}/hr | |
1st effect | 53 | 11 | 37 | 7.6 | 28 | 5.7 |
2nd effect | 48 | 9.8 | 35 | 7.2 | 26 | 5.3 |
3rd effect | 43 | 8.8 | 32 | 6.6 | 25 | 5.1 |
4th effect | 28 | 5.7 | 25 | 5.1 | ||
5th effect | 17 | 3.5 |
For General Consideration of evaporation rate taken for calculations
Quadruple Effect in Kg/m^{2}/hr | Quintuple Effect in Kg/m^{2}/hr | |||
Max | Min | Max | Min | |
1st effect | 35 | 30 | 35 | 30 |
2nd effect | 30 | 25 | 30 | 25 |
3rd effect | 25 | 20 | 25 | 20 |
4th effect | 25 | 20 | 20 | 15 |
5th effect | 15 | 10 |
Formulas for calculation:
The specific volume of evaporator body inlet vapour ( Si ) in M^{3}/kg(Taken from steam table)
The specific volume of evaporator body Outlet vapour ( So ) in M^{3}/kg (Taken from the steam table)
Volume of evaporator body inlet vapour in M^{3}/sec = [ (H x E x Si) /3600]
Volume of evaporator body outlet vapour in M^{3}/sec = [ (H x E x So) /3600]
( Note: For equipment flexibility purposes it is better to consider 10% extra vapour on actual requirement )
Dia of vapour Line = SQRT [ Volume of vapour / (0.785 x Velocity of vapour) ]
(SQRT = square root)
Online Calculator for Juice Heater Vapour Pipe Dia
Online Calculator for Evaporator Vapour Pipe Dia
Related Articles:
Design consideration parameters in Robert Evaporator Design.
Direct Contact Heater (DCH) Design Calculation with Online Calculator.
Flash Vapour Calculation | Flash Vapour Recovery Vessel Design Calculation.
Thumb Rules for Sugar Factory Equipment Design Sizing.
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8 thoughts on “Vapour Line Dia Online Calculation for Juice Heater and Evaporator”
Ramesh Chand Agarwal
(June 25, 2017 - 3:07 pm)Calculation is scientific.Use ful for learners
Manjeet singh
(August 11, 2017 - 5:02 am)This is very help full for sugar technogist it is good platform to find on line calculation thanks for this
siva alluri
(August 11, 2017 - 3:52 pm)thank you very much sir
Kuldeep chaudhary
(October 15, 2017 - 3:48 pm)Very nice
siva alluri
(October 16, 2017 - 12:40 pm)Thank you sir
Anuj
(June 27, 2018 - 11:03 am)What do you mean by SQRT in formula
siva alluri
(June 27, 2018 - 4:21 pm)SQRT means Square root
ishaque mohammad
(September 14, 2018 - 5:54 am)thanx