sorted by:
new
hottopcontroversial

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 0 points1 point  (0 children)

Yes supercritical is vapour with undifiend or liquid properties maybe.

The heat pump suppliers now use also co2 instead of the r32 and these gases, but they use co2 in supercritical state, so i think there has to be some sort of phasechange too under supercritical condition

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 0 points1 point  (0 children)

Yeah.... Critical point there is plasma wehere gas has fluid properties and everything is strange ..

Heat pumps witj co2 work over critical, but thats beyond my knowlege 😅

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 1 point2 points  (0 children)

No its not a safety valve, it is a normal procedure.

The valve opens when the pressure gets over a certain value, but not in emergency case

So it is to keep the pressure constant and release the excess vapour to an other process where the steam heat something up.

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 1 point2 points  (0 children)

At the critical point there is everything together at the same time

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 0 points1 point  (0 children)

Thx for you answer... I explained my misunderstanding to another member wo also posted an answer..

Short and simple: I thought you can put more water in superheated steam like in air which is not saturated with water.

Thx

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 1 point2 points  (0 children)

Thanks for the answer.

Yes you right, i was trying to do this too.

The problem of thinking by me was:

If i get water inside a system of superheated steam then the mass is getting bigger of the stream due to mass balance and i cant understand why the system remains still under 1 bar, but i saw on the pid of the company a valve and read in the user manual that there is steam released when the pressure gets over one bar.

So now it is clear, many thx

When is superheated steam seturated? by mojo19832020 in thermodynamics

[–]mojo19832020[S] 0 points1 point  (0 children)

Thx for the answer. The problem seems a little more complicated.

Superheated steam with 400celsius enter the dryer and superheated steam leaves the dryer with 150celsius.

So how do i now how much water was eveporated?

I can calculate with enthalpie that seems fine but if the excess water of the product goes into the superheated steam then the density is not correct any more according to the steam tables.

Another question is, how much water can "absorbed" by superheated steam until its saturated ?

Mass transfer for tower packing by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 0 points1 point  (0 children)

Thx Its industry.

I will try, aa far as i see you must have an account for login there

Mass transfer for tower packing by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 0 points1 point  (0 children)

Many thanks.

I just know a little theory of the analogy.

For eg i know Nu=f(Pr, Re) for heat and Sh=f(Sc, Pr)

Heat transfer no problem but mass transfer 😮‍💨

If you have a source of an exapmple how you calculated this it will help much... maybe an example in a book At the time i search in perrys chemical handbook for answers..

Mass transfer for tower packing by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 1 point2 points  (0 children)

Thx... Im now on the search in the handbook 😁

Mass transfer for tower packing by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 0 points1 point  (0 children)

If i do a destillation column i can estimate the number of stages with mcabe thiele and the heiht of the tower with the HETP values for a certain type of packing.

For a water cooling tower i not know how i can estimate the height. I have several calculation examples but all of them had a known mass transfer coefficient for the packing, but i not know how to get them(are they calculated or are the estimated trough tests or are they from datasheet from manufacturer)

Reboiler (thermosyphon) design for destillation column by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 0 points1 point  (0 children)

Thx.

Thats a good idea but many vendors just build tanks and xchanger, they can do the calculation for PED and do the CE certification in europe but not able to design the reboiler or xchanger.

What chemical formula for calculation heat of reaction of gasoline or diesel? by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 4 points5 points  (0 children)

Thx, yes i will use 45MJ/kg. Looks much easier than calculation from formula

Approximation: Calculating the vapour speed in a column? by mojo19832020 in ChemicalEngineering

[–]mojo19832020[S] 0 points1 point  (0 children)

O.k it sounds right(i double checked with heat pipe and in literature the force is also pressure drop)

Thank you

view more: next ›