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  • Sunday 9 October 2016

    Equipment Mapping



    Hello Readers....!! Happy to be back here....!!!
    Two days ago i got a query asking me to give some guidelines for Equipment mapping, and this seems to be a very interesting topic where everyone will have their own view which is convincing for themselves, and as i got this query to my mail i gonna present you here with my own view.

    Before getting into the topic all should have a little idea about Equipment Mapping and what does it means exactly......???

    Also Read:
    [How to] Avoid Packing failures in Pharma 
    [How to] Troubleshoot a pump  

    What is Equipment Mapping ??

    Equipment Mapping is the process/procedure to select and dedicate a particular material/equipment for performing a specific process on it by an qualified operator as per the predefined instructions.






    When is it required ??


    Equipment Mapping is necessary while going to achieve some target yield or to validate a process during a scale up, tech transfer, site transfer of a existing product or while performing a trial for a product that is newly manufactured.


    What are the Equipments that are eligible for Mapping ??

    The equipment which were mentioned in a particular Process flow/Piping & instrumentation Diagram, which are recommended while going for manufacturing of a product like Reactors, Receivers, Storage tanks, Filters, Filtration Equipments, Process Pumps, Vacuum Pumps, Dryers etc.

    Now, i think you got a basic idea of Equipment Mapping, so now Lets go deep into the topic,


    How to Map a Reactor ?


    Generally reactors were classified into different types based on MOC[Material of Construction], like SSR, GLR, Halar lined reactors, PPR etc.

    Based on the pH of the Reaction mass we can prefer the reactor, if the pH is 7 or above 7, we can go with SSR, or if the pH is below 7 we have to go with GLR or Halar lined reactors, as they were corrosion resistant.

    And you need to know how to prefer a reactor capacity ?


    If the reactor is used for carrying out reaction then the occupancy of the reactor should be in range of 30% to 60%,


    If a reactor is used for Work ups like extractions/washings then the occupancy should be in range of 40%-75%, if there is 75% occupancy during extractions then the agitator should be a turbine or propeller, if there is minimal occupancy then the agitator should be Anchor.

    For distillations/Product layer concentrations the preferred range of occupancy is 40-60%, as distillation is a Heat transfer operation the efficiency of Heat transfer will be high if there is Maximum occupancy but if the occupancy is more there may be chance of product carrying out into vapour line due to high vacuum. The most preferred agitator for distillation operation is Anchor.

    You might like reading:
    [How to] Evaluate the selection of ANFD technically ? 
    What to know from a RC1e study ?  

    How to Select Filters for filtration ?

    Filters were of many types, the mostly pharma involved filters were Micron filter, candy filter, Leaf filter, Sparkler Filter, Nutsche Filter, Pressure Nutsche filter etc.


    The above mentioned filters can be classified into two types based on their usage, 


    1) Multi time filtration,
    2) Single time filtration.

    Multi time filtration: The term Multi time seems to be an rare term, but for delivering its purpose through its name i've mentioned multi time filtration and don't get confused over that, The main purpose of the multi time filtration equipment's were to separate the large size particles from the slurries or solutions, these filters efficiency depends upon the filter medium like filter cloth, and the filters that fell under the Multi time filtration were Leaf filter, Sparkler filter. The Main reason for considering those two in this category is they were widely used for filtering the carbon slurries / charcoal slurries with re-circulation, during re-circulation the particles were left over the filter cloth in leaf filter and over the cellulose bed in sparkler filter, and the small size particles will also be retained over these filter medium upon continuous re-circulation, as the bed thickness increases over the medium the pore size decreases.







    Single time filtration: Single time filtration name itself denotes the filters from this category will be used only once in a whole filtration, it means every time a Multi time filtration filters will be accompanied by a single time filtration but it is used only once as a final effect, Micron filters, candy filters will come under this category as they will have low filtration area and finest pore size, they can resist even very fine size particles but can resist high volumes of particles over them.

    How to Map Receivers ?

    Usually receivers will be used for storage of solvents, product layers, impurity layers and some times during distillations to hold the distillate

    Receivers used for storage should be mapped based on occupancy, and receivers can have a maximum of 90% occupancy, if the occupancy is more, then the vapors generated due to saturation will be low as there wont be much space left in the receivers and this is simply called breathing losses of solvent, 

    Receivers used in distillation should have small capacities in order to increase the distillation effectiveness, this statement doesnt mean selecting a 10 L / 100 L receiver while distilling 2 KL or 3 KL, it means just to consider an optimized occupancy receiver which will enhance the rate of distillation, but not the one which will stay as a reason for low distillation rate.

    And the Transfer lines of the receivers should be of small length to avoid accumulation of solvent in the receiver and also the flow of solvent from the receiver to the destination should be mostly of gravity but not by pumping, and the lines in between the receivers and destination shouldn't have any negative slopes, which will retain the solvent as holdup volume.






    How to Succeed in Mapping of Filtration Equipments ?

    Mapping of filtration equipment's always remains as a  difficult task for an engineer, as even if the pore size of the filtration medium is of enough size, but the filtration wont happen due to the nature of the slurry, it may be of different reasons like pH, low temperatures etc., if the pH of the reaction mass is high then the mass will be sticky so the filtration rate will be low if a filtration equipment like ANFD is selected, and with the same filter cloth that is used in ANFD, if used for a centrifuge then the filtration may happen comfortably, so the Filtration equipment must be tested with our traditional method of Trail and Error without any hesitation, and some of the mass won't create that much headache as mostly they will be compatible with equipments like ANFD and Filter Press.

    if a reaction mass is compatible with ANFD then mostly it will have compatibility with centrifuge also, but being an engineer centrifuges should be avoided as they are of high hazard, and also the solvent loss during handling will be more.

    Also while mapping of the filtration equipment's like ANFD & PNF's, there should be some basic considerations. Out of which the major one is cake height.

    You might like reading:
    [How to] Select a condenser for a reactor? 

    [How to] Select a Batch Size ?  

    I'll show you how to select an ANFD / PNF.

    The cake height in these filters should be 20% of the total height. If its ANFD the cake height shouldn't be higher than the stoke height.

    Lets suppose the expected wet output will be 30 Kgs, so for this case we need to map an filtration equipment, and lets consider that the filtration is fast.

    So we can go further with ANFD or PNF. Now we need the capacity of the filter.
    Let the BD of the material is 0.3 Kg/L. 
    So the volume occupied by the wet cake will be 30/0.3 = 90 L.

    We are having two PNF's and we need to select one outta those, 
    1st filter capacity is 0.25 Sq.m(0.8 m height), 2nd filter capacity is 0.5 Sq.m(1.0 m height).

    Considering the 1st filter, the cake height would be 0.09/(0.25) = 0.36 m
    The height percentage would be ( 0.36 / 0.8 ) x 100 = 45 %.

    Considering the 2nd filter, the cake height would be 0.09/(0.5) = 0.18 m
    The height percentage would be ( 0.18 / 1.0 ) x 100 = 18 %.

    So, as in the 2nd filter case the height percentage is below 20%, we can comfortably proceed with it.






    The reason behind the 20% is that the remaining empty space will attribute to the adequate press dry with nitrogen pressure. Hence the expulsion of the ML's / filtrate would be good enough.


    Here, Stoke means the length of the agitator shaft.

    How to Map Drying Equipment's ?

    Drying Equipments are the most critical one in pharma Industry, as the yield mostly depends on them on the final stage of manufacturing, mostly filtration equipments will be accompanied with drying setup also, and some times drying will be a part of product concentration equipments as like ATFD[Agitated Thin Film Dryer], APD[Agitated Pan Dryer] etc, and these drying equipments will be two types,

    1. Direct Contact Dryers,
    2. Indirect Contact Dryers,

    If a material is hygroscopic then Indirect contact dryers should be preferred, as if we go with a direct contact dryers, the material may transform it self into liquid,

    There are many types of dryers available in market like Vacuum tray dryers, Rotary cone vacuum dryers, agitated thin film dryers, Agitated nutsche filter dryer, Air tray dryers, Agitated pan dryers, Fluidized bed dryer etc.


    Mostly if the material is having tendency to loose the solvent or water content from its lattice and wherever agitation is required, then its better to go with dryers like ANFD, APD. 


    And if the batch manufacturing process is off small scale and the solvent to be removed is having high volatileness, then its better to go with Vacuum tray dryers/tray dryers.







    If the Crystal lattice is having a high tendency to hold water content/solvent content, then the material should be taken for size reduction with a miller and after reduction it should be taken into a dryer like FBD, where direct heating takes place.


    And finally coming to dryers like ATFD[Continous dryer], APD, these are far critical equipments than other dryers, they can be used from product layer concentration to final stage drying.


    Finally, what ever may be the capacity of the dryer, it should have a maximum occupancy of 60-70%, as if there is high occupancy than the mentioned then the vacuum that needs to perform its job would be uncomfortable, i mean the vacuum contact area with material will become low, and the efficiency of drying will become less.

    That's it......!! This is upto my knowledge and hope you will understood this simply,


     If anything to be added from your knowledge, comment here or mail me, 


    Comments were appreciated........!!!




    Related Posts:
    [How to] Calculate power required for an operation ? 

    [How to] Calculate time-cycle required for heating/cooling ?  
    [How to] Calculate vapour column diameter ?  
    [How to] Calculate time-cycle required for distillation ?   


     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


    22 comments:

    1. Its really an interesting topic. You shared many information and guidelines for equipment mapping. Which is helpful for readers who have less knowledge of mapping. Thanks for sharing.

      Click Here

      ReplyDelete
    2. If a material is hygroscopic then we have to prefer Indirect contact dryers, as if we go with a direct contact dryers, the material may transform it self into liquid why ??????

      ReplyDelete
      Replies
      1. Hiii Mr. Ramaiah,

        Glad you visited my site, Hygroscopic nature means absorbing moisture from atmosphere and ultimately turning its physical state into liquid, i think you already know that,

        the point is that when ever we are preferring a direct contact dryer like FBD, the blower will suck the atmospheric air and gets heated with a steam coil and it will be pressurised as a reason the material will absorb the moisture from the heating source, and finally transforms into liquid, in such case we need to used cylinder nitrogens which will have very low moisture content.

        Regards,
        AJAY KUMAR

        Delete
      2. Hi ajay,

        thank you for your comment

        If i maintained dew point of air below -40 deg c what will happened ????

        Regards,
        seetha ramaiah

        Delete
      3. Dear Sir,

        And what's the operational temperature you want to maintain ?

        Regards,
        AJAY K

        Delete
      4. Ajay,

        Let us assume that we are performing the Jet mill operation using Nitrogen because of material having gyroscopic nature why con't we perform the same operation using air if I am maintaing the dew point of air below -40 deg c

        Delete
      5. We can do that but with calculated risk,

        Regards,
        AJAY K

        Delete
    3. Plz send dryer design calculation...

      ReplyDelete
    4. What is the maximum occupancy we can use for RCVD?

      ReplyDelete
    5. Vacuum tray drier and tray drier

      ReplyDelete
    6. Dear Sai,

      we can go upto 50%, but optimum occupancy will be 30%.

      Regards,
      AJAY K

      ReplyDelete
    7. Please share the centrifuge filtration rate and time calculations (24 inch centrifuge)??

      ReplyDelete
      Replies
      1. Dear ,

        Sorry for late reply,

        Follow the below link for calculating the filtration rate,
        http://pharmacalc.blogspot.com/2018/08/evaluate-filtration-feasibility-in-anfd.html

        Time can be calculated based on the R&D study, whatever the pressure we have used for filtering in R&D can be matched with the angular force per unit area of centrifuge, it is calculated as P = m x r x (omega^2) / A.

        m is the mass of the material,
        r is the radius of the centrifuge,
        omega is the revolutions per second.

        ** From next time kindly comment with your good name plz.

        Best Regards,
        AJAY K

        Delete
    8. Very useful information.....Thanks

      ReplyDelete
    9. In pnf for calculating cake height what is 0.09

      ReplyDelete
      Replies
      1. Hii, the wet cake volume is 90 Land i've converted the 90 L to m3, which will be 0.09 m3.

        Regards,
        AJAY K

        Delete
      2. Thanks...
        Also I want to know how will we know reactor suitability in terms of tip speed, thermopocket touch volume and other parameters.

        Delete
      3. Dear ,

        It depends on the operation, if its a reaction the we will proceed with 60-70% maximum occupancy and if its a workup then 80% will be the occupancy.
        And before proceeding to such extent we will cross check the thermowell touch volume in reactor whether the mass is sensible or if the sensor is not touching then we may proceed with extension of the thermowell(for SSR) or replacing for GLR.
        Coming to tip speed, it is just a comparison during scale-up or scale down, and if we want to maintain a particular tip speed during an operation then, it can be calculated as shown above.
        If any in-depth queries pl write me at pharmacalc823@gmail.com.

        Regards,
        AJAY K

        Delete
    10. minimum and Maximum occupancy for hydrogenation reaction?

      ReplyDelete
      Replies
      1. 30 - 70% can be considered as healthy for hydrogenation

        Delete

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    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.

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