![when to use depriester chart when to use depriester chart](https://i.ytimg.com/vi/g9u3otWC-Jk/hq720.jpg)
Since you are solving for T which is not explicitly defined in this equation, you will need to either use trial, error, and the DePriester chart to find T or find the DePriester chart in equation form and solve that set of equations (Wolfram or Excel Goalseek). Use the respective mole fractions for the y's. To be clear, the parentheses indicate that K is a function of T and P, not any arithmetic. To finding the dewpoint solve the following equation: The DePriester chart does not include nitrogen, but it is probably safe to assume its K is effectively infinity for the conditions you are using since its boiling point is much lower than the other components. Where y and x are the mole fractions of that component in vapor and liquid respectively. Section 5 has information on dispelling some of the assumptions I mentioned above.įor methane and ethane, you can use a DePriester Chart to determine the vapor/liquid equilibrium ratio of each component for any temperature and pressure. This problem can be as involved as you want it to be.Įdit: Here is a nice little summary for the uninitiated.
![when to use depriester chart when to use depriester chart](https://lasopacenters282.weebly.com/uploads/1/2/5/7/125773725/895636382.png)
There are more corrections to be had if you want to eliminate some assumptions. This is, in my view, a thermo for Chem E's probablem. You want a lowish pressure (which you have) and really similar components (methane & ethane) to be more confident in this assumption, but my intuition says that nitrogen will probably play well with them. You can probably get away with assuming ideal gas/liquids and using raoult's law. There might be something available since these are all pretty standard chemicals, but I'll leave that to you. You can google around, but as systems grow more complex it gets exponentially more unlikely to be able to find nice experimental data to make your life easy. No, you can't simply consider how the substances behave in isolation and choose the highest dewpoint. Meme posts made outside this time will be removed. Meme posts are allowed only Saturday, Sunday, and Monday. You can be an account with a website, but not a website with an account. Trolling, posts intentionally inciting conflict, personal attacks, and spam will be removed.Īvoid posting blogspam, blog self-promotion, or personally monetized links. Racism, sexism or any other kind of intolerance or discrimination will not be tolerated. Otherwise your post may get deleted.ĭo your own research, follow basic guidelines, and be sure to google your question beforehand. If the topic of your post is currently covered in one of the megathreads/stickied posts at the top of the page, please put your content as a comment there instead. Not reading them and then complaining will not earn you any sympathy. This is a place for engineering students of any discipline to discuss study methods, get homework help, get job search advice, and find a compassionate ear when you get a 40% on your midterm after studying all night. Check out the official EngineeringStudents Discord!: discord.gg/EngineeringStudents ↑ "Define and use K values, relative volatility, and x-y diagrams".Unit Operations Handbook: Volume 1 (In Two Volumes). ↑ "Pbub and Pdew calculation based on the DePriester chart for a fast pyrolysis and hydrotreating process".Read this K-value off the chart (approximately 21.3). Note where the line crosses the methane axis.Connect the points with a straight line.
![when to use depriester chart when to use depriester chart](https://s3.studylib.net/store/data/008860220_1-deeea6fe940cd6dd694d6d5ddaf0cad5.png)
On the right-hand vertical axis, locate and mark the point containing the temperature 60☏.On the left-hand vertical axis, locate and mark the point containing the pressure 100 psia.
![when to use depriester chart when to use depriester chart](https://us-static.z-dn.net/files/dbd/d9fb819047e76d670172c6b79ea9f34d.jpg)
Exampleįor example, to find the K value of methane at 100 psia and 60 ☏. Many DePriester charts have been printed for simple hydrocarbons. "K" values, representing the tendency of a given chemical species to partition itself preferentially between liquid and vapor phases, are plotted in between. These nomograms have two vertical coordinates, one for pressure, and another for temperature. DePriester in an article in Chemical Engineering Progress in 1953. DePriester Charts provide an efficient method to find the vapor-liquid equilibrium ratios for different substances at different conditions of pressure and temperature.