3 replies to this topic

[Venkat @89]

It is very common in hydrotreating units to inject wash water to remove salts of Ammonium to avoid under deposit corrosion. Condition is that injected washwater of minimum 25% should remain in liquid phase.

20000kg/hr Washwater is injected at location where pressure of the Liquid and vapor mixture of hydrocarbon stream is 45 kgf/cm2g and temperature is 220degC. (Approx mass flow rate of the HC stream is 250000kg/hr).

How to evaluate amount of washwater is in liquid and vapor phases?

For pure component system, it is quite simple to say based on saturation temperature and pressure of water.

Water is getting injected into a HC stream where partial pressure of water vapor in the stream is zero, so how will I know the percentage of wash water that will be in Vapor and liquid phase?

Kindly guide me.

[shvet1]

You need a proper background. It is better to leave this issue to the professionals.

 

https://www.amazon.c...g/dp/0070116822

https://en.wikipedia...cess_simulators

https://www.google.c...nt=gws-wiz-serp

https://www.chemical...ference-library

Edited by shvet1, 17 September 2023 - 11:13 PM.

[Venkat @89]

Thank your reply shvet1 sir.

Would like to understand the process, how to approach such kind of calculations without simulators.

Thank you sir.

Edited by Venkat @89, 18 September 2023 - 02:28 AM.

[PingPong]

This is not something that can easily be done by hand because you have a Liquid and Vapor mixture of hydrocarbon stream.

 

By injecting water the temperature of that mixture will drop (due to water vaporization) and consequently the hydrocarbon V/L equilibrium will change: you end up with less vapor and more liquid (due to some HC condensation). Also the specific heat of V and L change when temperature and composition change.

Edited by PingPong, 20 September 2023 - 04:11 AM.