For Engineer By Engineer

  • Sunday 8 May 2016

    [How To] Select a Condenser

    Happy Weekend viewers.....!!!

    Very Happy to receive such a great response regarding the post Agitators Types and Their Significance

    Today i wanna provide you some basic knowledge regarding selection of Condensers, Without a condenser there is no topic of solvent recovery, the life of a chemical engineer in a pharma industry rotates around Solvent recovery, this is fact, there may be a role of chemical engineer in some niche like process engineering, techno-transfer, but solvent recovery is a basic Mass transfer Operation, so the Core application of chemical engineering lies in Solvent Recovery.

    Also Read:

    With many variety of condensers available in the market we need to know the significance of each type of condenser, any everywhere it will be the duty of a chemical engineer to select a condenser from those many available, So, Before going into the topic of selection of Condenser, you need to have a basic knowledge, Regarding

    What is a Condenser?

    A Condenser is an equipment which is designed to condense vapour state matter to liquid phase. The temperature change of the condensate from its boiling point is not the duty of the condenser but it will occur routinely. 

    Recommended Read:

    ** How to Calculate Time-Cycle required for Heating/Cooling for a Pharmaceutical Operation? 

    ** How to Select a Vacuum Pump for an pharmaceutical Operation?

    What are the types of Condensers, that are majorly used in industry [Based on Application] ?

    Based on the Purpose condensers were used in different applications, and there are many classifications. But generally we classify condensers into two types, 1. Air Cooled, 2. Water Cooled, 3. Evaporative.

    What is a Air Cooled Condenser?

    Air Cooled Condensers use the ambient air to cool the process fluid, and these are very rarely used in industries.

    What is water cooled condenser?

    These are of many types like double pipe condenser, shell and tube condenser, plate and frame, spiral condensers etc, which uses water or water mixed composition volumes to cool the process fluids.

    What are Evaporative Condensers?

    These are majorly seen in Chiller plants where the high Pressure refrigerant vapor is being cooled by water spray over the vapor containing tubes.
    Classification based on the nature of Condensate or MOC :

    Majorly classified into 3 types.1. SS Condensers, 2.GlassLined Condensers, 3. Graphite Block Condensers.

    Majorly portion is occupied by SS condensers, and Glass Lined Condensers were used where acidic nature vapors evolve, Graphite Block Condensers where used instead of Glass lined condensers to increase the rate of condensation.

    Why its Graphite?

    Graphite is a corrosion resistant material of construction which gives no ion pick up, hence it is suited to applications mainly within the fine chemical pharmaceutical and fine chemical industries.

    Whats the need for Blocks inside Graphite Condensers?

    Due to high level of compactness and easy to maintain when compared to glass lined, also these involve less wasteful of materials.
    Credits: SecoMak Ltd.

    What is the advantage of Graphite over Glass Lined?

    Graphite is a more thermally efficient material of construction, typically using 1/2 to 1/3 the heat transfer area required by a glass unit.

    And Now its the Trend of Tantalum Condensers in pharma industry. See the below Overall Heat Transfer Co-efficient values for Tantalum Condensers.
    So, Now you got a basic idea for selecting a Condenser depending on MOC and Application.

    Now we can enter the point how to know the rate of condensation that a condenser can ?

    Generally the rate of condensation depends on the Area of Heat Transfer, Utility temp, Process Fluid Temp., etc.

    So, We can calculate the Rate of Condensation based on the Area of heat transfer, by using simple calculation but for that we need to know the U value appropriately, for that we have a tabulated data.

    So, With this data you can calculate the maximum possible condensate rate of organic vapors in a condenser, using the below formula,

    Rate of Condensate = ( U x A x LMTD ) / ( L )

    U - Overall Heat Transfer Co-efficient,
    A - Heat Transfer Area,
    L - Latent Heat of Vaporisation of vapor.

    If you Understood the above Theory, then Say Cheers........!!!

    Still any queries we are happy to help you....!!

    Comments are most appreciated....!!

    Also Read:

    About The Author

    Hi! I am Ajay Kumar Kalva, Currently serving as the CEO of this site, a tech geek by passion, and a chemical process engineer by profession, i'm interested in writing articles regarding technology, hacking and pharma technology.
    Follow Me on Twitter AjaySpectator & Computer Innovations


    1. Cheerzz.. ☺
      Had a query regarding heat of rxn..
      How enthalphy acts in rate of rxn, from that we decide type of rxn(exo/endo).
      From hess law, we can identify change in enthalphy.
      What is the basis for H values.
      Give me a clear description for heat of rxn n pharma and its importance.
      What's the safety measures to be taken fr rxns ?

    2. Hess law mentions that, " either a reaction may be carried out in single step or multiple steps, the energy liberated oe added will be the same", and Enthalpy means the energy that is being added or liberated to the basic energy at 25 degree centigrade.

    3. Hello ajay.pls help me to find out U- calculation in reflux line of reactor for traping the vapour going back to condenser.specifically the height of U-loop

      1. the height of U loop can be calculated as, P = rho x g x H, height - H, rho - Density, P is vapour pressure calculate it from antonie equation....


    4. Hello ajay.your blogs are very knowledgeable and interesting.i have one quarry regarding reflux line design.i want to find out the U-loop calculation of reflux line of reactor for trapping the vapour going back to the condenser.specifically the height of U-loop.waiting for your response.

    5. Hello ajay pls give me the U loop calculation of reflux line of reactor.

    6. At steady state (under total reflux),
      UA(LMTD)for condenser and reboiler will be the same?

      1. Dear Natasha,

        According to me, this query doesn't make any sense, because the area itself will vary for both condenser and re-boiler, and that to the condenser duty is a continuous one, so usually by default the heat duty will vary atmostly.

        AJAY K

    7. Why is U-loop required in reflux line?

      1. Dear Natasha,

        The main purpose of the U loop in the reflux line is to break the back pressure that is generated by the condensate liquid coming from condenser,

        If the U loop is absent then during reflux reactions the condensate coming back into reactor will create some back pressure over the vapour that is generating inside the reactor.

        Any queries feel free to comment/contact.

        AJAY K

    8. Replies
      1. Dear Mohan,

        Condensers can be defined based on MOC, type.
        Usually we will have shell & tube, plate type, spiral, plate & frame,double pipe, graphite.
        If its based on MOC, it will be SS316, Hastelloy, Tantalum etc.

        Best Regards,
        AJAY K

    9. How to calculate liquid nitrogen requirement for cryo reaction in pharmaceutical industry?

      1. Hii Suresh,

        Glad to hear from you,
        Lets say you have a reaction and the heat of liberation would be 50000 KCal,
        And we should balance this heat using MCpdT,
        M = 50000 / (0.49 x 15) = 6802 Kgs = 6802 / 804 = 8.46 KL.
        0.49 is Specific heat of Liquid Nitrogen, 15 is Maximum possible dT, 804 is Liquid nitrogen density in Kg/m3,
        Liquid nitrogen temperature would vary between -195 C to -210 C.


    This Blog is protected by


    Hi! I am Ajay Kumar Kalva, owner of this site, a tech geek by passion, and a chemical process engineer by profession, i'm interested in writing articles regarding technology, hacking and pharma technology.

    Like Us On Facebook