Triple-Effect Evaporator: Introduction

Organized by textbook: learncheme.com/ Describes the operation of a triple-effect evaporator to concentrate a solute liquid solution using significantly less energy than a single-effect evaporator. Made by faculty at the University of Colorado Boulder Department of Chemical and Biological Engineering.
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[@ShubhamKumar-wx5yc]

Well Explained sir!! Love from India

[@zenithpatel2473]

If boiling point in second effect is lower then first effect, then why do we use steam in second effect, bcoz feed in second effect is alredy at higher temp then boiling point i.e. t1>t2

[@pploy-yy8dt]

what's about "mix feed" and "parallel feed"
i wanna know those equation for calculation, please

[@michaelmolter8828]

Does this only work for processes where you’re concentrating a solid, and would expect 0% product to be coming through in the vapor stream?

[@farahsa9984]

I believe q can’t be same at all areas since there is always some losses as stem gets does not compeltely condensed.
We must take that too in calculation

[@vishalkumarsharma2070]

good method to explain

[@curtis3041]

Your video on backwards flow dilute solution is more realistic to real life use.
Counter flow design is always the goal with heat exchanging.

[@willcaruthers3984]

'Always' is such a good word to excise from your vocabulary as an engineer. For example, in food ingredients production (like corn syrup), the feed flow is generally (much better word than always, as it allows for applications I'm not aware of) introduced in its most diluted state to the hottest, highest pressure steam in the first effect. Thus, each successive effect sees a more concentrated feed and subjects it to a lower temperature. This avoids scorching and introducing color to the product, something that is absolutely to be avoided. In corn syrup production if we were to reverse this (as I think you're suggesting, sorry if I'm mistaken) and introduce the most concentrated sugar solution to the hottest steam in the first effect, we would need less total surface area among the effects for the same ultimate evaporation but we'd likely wind up with baked, yellow-brown product that no one would want to buy. In real life, more variables than just capital cost are floating around out there.

[@fikria.haekal1751]

Thank you so much

[@JINAl1992]

hello sir
want to ask you about how you find steam flow rate to 1st effect by energy balance using steam table

[@engzahraa7842]

How can l calculate the changer when we have anumbers not just the mechanisum😧💔

[@tuanphamquoc8825]

I'm looking for the material about Falling Film Evaporator. Anyone have?

[@anukritisingh0509]

How to find optimum number of effects any formula

[@IRuvJndL]

Is there a reason why saturated steam is used instead of superheated steam to evaporate the liquid solution?

[@9825037425]

superheated steam is at very high temperature then saturdated steam . becouse of that product solution can be burn out or in case of juice or koffee plant . test of juice or coffee is bitter. its better to get concentration at particular temperture . steam stage is on saturation curve line . neither fully saturday or neigher superheated to get maximum benefit of heat

[@ystineompad1677]

superheated steam has a higher temperature compared to saturated steam. however, its heat transfer coefficient is significantly lower than that of the saturated steam.

[@willcaruthers3984]

IRuvJndL One other consideration, if steam is provided by a general plant or facility supply it is most commonly saturated stream by the time it reaches the process building. Superheated steam is of course generated at times for specific applications that require a higher temperature (such as slightly superheating evaporated vapors before they enter a mechanical recompressor to ensure no liquid droplets are present), but as you will expend more total energy superheating the steam than you'll realize in additional energy transference in the evaporator it is only done where needed.

[@WasitLimprasert]

many thanks :)

[@krishnagubili1724]

Thanks much

[@chouayasana2565]

very nice

[@fahmylina123]

OUR invention avoids the extra-energy needed for water boiling and the safety problems associated with the old systems

[@davidvalero8275]

How it's possible that liquid 2 and vapor 2 be cooler than V1 and T1? Who received that energy? I'd think that T2 would be equal to T1 because you are "heating" a liquid with a Vapor, both at the same temperature. I mean, temperature vapor inlet = temperature liquid inlet and the result is temperature vapor outlet = temperature liquid outlet, T1>T2, WTF?

[@LearnChemE]

Great questions. Temperatures are not the only changes here. Note that the different units are operating at different pressures, so the saturation temperatures have changed which allow for a different equilibrium state. There are also phase changes in both the heat transfer liquid and within the evaporator. A simple answer to your initial question is that that energy went into evaporating more liquid.

[@kharavela9088]

This was my doubt and now it is cleared. Thanks @LearnChemE

[@anukritisingh0509]

Sir how to find number of effects

[@LearnChemE]

This is simply the number of evaporators that is being used.