Condensate Receiving Tank Design Calculation | Condensate Mound

Condensate Receiving & Condensate Flash Recovery tank design

Abstract : Condensate receiving tank or condensate mound is one of the simple equipment in sugar industry and other process industries. If we provide common condensate flash recovery tank then no need to provide individual mounds for each evaporation or heating bodies like juice heaters, evaporator bodies, pans .. etc.

Here explain about calculation of sizing requirement for condensate receiving tank (Condensate mound). Also explain the design concepts of single flash recovery condensate receiving tank and its flash line sizing.

Concepts to find the sizing of the condensate receiving tank:

a) First we conform the purpose of the the condensate mound. I.e It is either condensate receiving tank or condensate flash vapour recovery tank.

b) Find the condensate quantity to handling the condensate mound.

c) Parameters of the condensate water and its flash vapour like temperature, density, velocities, latent heat, specific volume … etc.

d) Calculate the flash vapour velocity at the time of generation from condensate. Its velocity calculated by the  “The Souders – Brown equation”

Velocity of flash vapour in flash tank(m/sec) = Umax = C x [ (ρ L – ρV)/ ρV]0.5

Condensate Water Density = ρ L in kg/M3

Flash vapour Density = ρ V in kg/M3

Here C = The value of the constant.

C is a measure of the droplet size that will be carried over and depends on the degree of separation of liquid and vapor required.

According to Cane sugar engineering by Peter Rein , coefficient C recommended 0.01 m/s.

Now calculate flash vapour quantity and its velocity in condensate mound. From this we can easily calculate the dia required for condensate receiving tank.

For common condensate flash recovery system purpose please go through the following link

Flash Vapour Calculation | Flash Vapour Recovery Vessel Design Calculation.

For simple condensate receiving tank purpose, flash vapour to be taken only for 2 to 3oC of the inlet water temperature.

a) Generally the height of the condensate receiving tank required for  1.5 to 2.0 meters with the calculated dia.

b) Provide partition plate in the middle of this condensate mound. Insert the condensate inlet line in partitioned portion(opposite to the condensate outlet line).

c) Bottom of the condensate line provide minimum 200mm gap from the bottom plate of condensate mound. The partition plate height to be provide minimum 500mm less than the total height of the condensate mound.

Condensate Receiving Tank Design Calculation | Condensate Mound | Condensate Receiving & Condensate Flash Recovery tank design

Now take one example to calculate the sizing of the condensate receiving tank and condensate flash vapour recovery tank.

Condensate Receiving Tank ( Mound )Calculation

S.NO DESCRIPTION Symbol / Formula VALUES UOM
1  Condensate Quantity Qc 50 M3/hr
0.013889 M3/sec
2  Condensate inlet temperature Ti 125 oC
3  Condensate outlet temperature (To be take 2 to 3oC diff.) To 123 oC
4  Condensate water outlet velocity from mound Vc 0.5 m/sec
5  Flash vapour velocity in vent line or equalizing line Vf 50 m/sec
 U= Flash Vapour maximum velocity in condensate mound
 U = C ((ρL  –   ρV)/ρV)0.5
 Condensate water density ρL 939.00 kg/M3
 Flash Vapour Density ρV 1.30 kg/M3
 Coefficient C 0.01 m/sec
 Specific volume of flash vapour µ 0.77 M3/kg
 Latent Heat of flash vapour λ 522.50 Kcal/Kg
 U 0.27 m/sec
  Flash vapour Quantity Qv = Qc x (To – Ti) / λ 0.19 T/hr
191.39 Kg/hr
 Qv x 1000 x µ 147.38 M3/hr
0.04 M3/sec
 Condensate Mound Dia
 Flash vapour Quantity Qv 0.04 M3/sec
 Flash vapour velocity in mound U 0.27 m/sec
 Cross sectional area of mound Am = Qv/U 0.15 m2
 Condensate mound Dia Dm =  sqrt ( Am /0.785) 0.44 mtr
450 mm
Condensate mound vent or equalizing  line Dia
 Flash vapour Quantity Qv 0.04 M3/sec
 Flash vapour velocity in vent line Vf 50 m/sec
 A Av = Qv / Vf 0.00082
 Flash vapour Line Dia Dv = sqrt ( Av /0.785) 0.032 mtr
i .e 50 mm
Condensate mound outlet water line Dia
 Condensate Quantity Qc 0.0139 M3/sec
Vc 0.50 m/sec
 Cross sectional Ac =  Qc / Vc 0.0278 m2
 Condensate water oulet line dia Dc = sqrt ( Ac /0.785) 0.1881 mtr
200 mm
  Cross check the dia by this formula  D > 1.116 x (Qc)0.4
 Condensate mound outlet water line Dia 201.71 mm

Individual Flash Recovery Condensate Mound Calculation

S.NO DESCRIPTION Symbol / Formula
VALUES UOM
1  Condensate Quantity Qc 50 M3/hr
0.013889 M3/sec
2  Condensate inlet temperature Ti 125 oC
3  Condensate outlet temperature.(After Flash) To 105 oC
4  Condensate water outlet velocity from mound Vc 0.5 m/sec
5  Flash vapour velocity in flash outlet line Vf 50 m/sec
U= Flash Vapour maximum velocity in condensate mound (At the time of generation)
 U = C ((ρL  –   ρV)/ρV)0.5
 Condensate water density ρL 939.00 kg/M3
 Flash Vapour Density ρV 1.30 kg/M3
 Coefficient C 0.01 m/sec
 Specific volume of flash vapour µ 1.42 M3/kg
 Latent Heat of flash vapour λ 535.75 Kcal/Kg
 U 0.27 m/sec
 Flash vapour Quantity Qv = Qc x (To – Ti) / λ 1.87 T/hr
1866.54 Kg/hr
 Qv x 1000 x µ 2648.33 M3/hr
0.74 M3/sec
Condensate Mound Dia
 Flash vapour Quantity Qv 0.74 M3/sec
 Flash vapour velocity in mound U 0.27 m/sec
 Cross sectional area of mound Am = Qv/U 2.74 m2
 Condensate mound Dia Dm =  sqrt ( Am /0.785) 1.87 mtr
1870 mm
Condensate mound flash outlet  line Dia
 Flash vapour Quantity Qv 0.74 M3/sec
 Flash vapour velocity in vent line Vf 50 m/sec
 Cross sectional area Av = Qv / Vf 0.01471
 Flash vapour Line Dia Dv = sqrt ( Av /0.785) 0.137 mtr
i.e 150 mm
Condensate mound outlet water line Dia
 Condensate Quantity Qc 0.0139 M3/sec
Vc 0.50 m/sec
 Cross sectional area Ac =  Qc / Vc 0.0278 m2
 Condensate water outlet line dia Dc = sqrt ( Ac /0.785) 0.1881 mtr
200 mm
 Cross check the dia by this formula  D > 1.116 x (Qc)0.4
 Condensate mound outlet water line Dia 201.71 mm

Online calculation for Condensate receiving tank and flash vapour recovery condensate mound

Click Here

Some related articles

Sugar Industry Related Important Websites | sugar Technology

Sugar Industry Equipment Design and Drawing Online Calculations.

Shell and Tube Multipass Heat Exchanger Design | Tubular juice heater design calculation with online calculator

For online steam table  Steam Table for Saturated Steam

Hi friends Thanks for reading. I Hope you liked it. Give feed back, comments and please share it.

Post Author:

5 thoughts on “Condensate Receiving Tank Design Calculation | Condensate Mound

    VijayKumar Dure

    (October 31, 2017 - 4:15 pm)

    It’s usefull site I learn much more thanks

      siva alluri

      (November 1, 2017 - 1:01 pm)

      Thank you
      The “www.sugarprocesstech.com” invites to all sugar technologists to share your knowledge, achievements in your working organization and new developments and technologies in sugar industry and its concerned units. It is very much helpful to show your identity to the world at the same time it will helpful to another technologist to enhance their insight and enhance great execution in there working. This website also provides the basic knowledge in sugar industry technologies and equipment design calculation with online calculators.
      sugarprocesstech@gmail.com

    Pranav

    (April 22, 2021 - 10:04 pm)

    Very informative website. Nicely explained the content. I have few queries regarding sizing of condensate storage cum flash tank.

    Ram veer

    (June 28, 2021 - 8:54 am)

    Dear sir my question is about steam consumption.
    If any pan dropped at same time steam consumption reduced i.e. syrup brix effected. In this situation how much evaoporation should be increased in evaporators that syrup brix will maintain

Leave a Reply

Your email address will not be published. Required fields are marked *