Hi Michael, usually you would solve this by adding a throttle valve after the feed stream with 210 psig where you reduce pressure to 100 psig. This is an adiabatic operation wher you will see also a temperature change. Now you will feed into the adiabatic flash vessel where you separate the phases without any further exchange of energy. Just do it like in real live! You always will have some kind of valve to reduce pressure in advance to go to such a vessel. Otherwise this process wouldn't be well...
Hi Michael, usually you would solve this by adding a throttle valve after the feed stream with 210 psig where you reduce pressure to 100 psig. This is an adiabatic operation wher you will see also a temperature change. Now you will feed into the adiabatic flash vessel where you separate the phases without any further exchange of energy. Just do it like in real live! You always will have some kind of valve to reduce pressure in advance to go to such a vessel. Outherwise this process wouldn't be well...
Hi Daniel, i installed WinPython 3.9 from link you provided on Sourceforge. I also checked the installation of Python is working via Spyder. I still get an error on running Reaktoro PP: Please, could you have a look? regards, Gregor * This error was raised during the calculation of a Unit Operation or Material Stream. System.TypeInitializationException: The type initializer for 'Python.Runtime.UcsMarshaler' threw an exception. ---> System.IO.FileLoadException: Could not load file or assembly 'System.Runtime.InteropServices.RuntimeInformation,...
Hi Daniel, thanks for that information. I will check this out. Please, could you update the information on your website regarding Reaktoro ? Do you have a working sample file which might be included to sample files directory to demonstrate usage of that PP?
Hi Daniel, I'd like to remember you of that issue as suggested. I installed Python from the link you suggested within the property package. p.s.: i defined Python path in general settings: C:\Users\xxxxxx\Python\WPy64-310111\python-3.10.11.amd64
Hi Daniel, I'd like to remember you of that issue as suggested. I installed Python from the link you suggested within the property package.
Hi Daniel, i just installed Python and added the link of the folder into the general settings. Then i created a new simulation with Reaktoro-PP and Water, NaCl, Na+ and Cl- as components. I also added a new equilibrium reaction NaCl <-> Na+ + Cl- A new stream with Water and NaCL was created. Now i get a new error message on calculation: Location: Code Location: InitializePythonEnvironment (file 'C:\Users\g90020\source\repos\DWSIM\DWSIM.GlobalSettings\Settings.vb', line 209) Calling Method: Flash_PT...
Hi together, i fetched actual code from GitHub and compiled the projekt. With this actual version Reactoro-PP should work without an additional python environment. I tried this, but DWSIM complains that there is no link to a Python installation folder. What is going wrong here? Please help.
Hi together, i fetched actural code from GitHub and compiled the projekt. With this actual version Reactoro-PP should work without an additional python environment. I tried this, but DWSIM complains that there is no link to a Python installation folder. What is going wrong here? Please help.
On using well definied components, i would try to use ideal PP. Phase change with melting is possible generally.
I recomend to use MODFAC-NIST as property package. This model is able to account for different temperatures and has highes quality of interaction parameters.
Hi, yes, you should do this either by wizard for solids definition or by compound creator utility. You need to define the elements directely as no UNIFAC or Joback groups can be defined. Therefore you need to define all required properties manually as no Joback groups are definied to do that job for you.
Hi, the depicted molecule is a polymer and should be defined as a solid with help of the wizard. As an alternative i created a (monomer)compound with by compound creator with two rings beeing connected. Problem: This compound can't be definied by UNIFAC/MODFAC as the required group "ACO" is missing in these models. Therefore only Joback-groups were definied directely. This allows to estimate physical properties of this compound. I hope this helped? Gregor
Hi Fortune, to add biomass as new component, this is the way to go! Define it by entering the element composition. But be aware to define all required properties (at least proxy values).
I modified your definition: * remove all UNIFAC groups - you can't use this model as the group for oxygen in ring is missing here. * From UNIFAC groups the Joback groups are automatically defined. This is not possible from MODFAC and has to be done manually therefore. * I added the correct groups inbothe MODFAC models * I assigned the required Joback groups -> now you can try to calculate parameters automatically. Molecular weight is calculated automatically from Joback groups now. I hope this h...
@Daniel: probably it would help if the error message is modified to tell the user that a recycle block needs to be added.
Please be aware that CO2 solubility in water is calculated by Henry coefficient. DWSIM automatically decides how to calculate this depending on temperature beeing above or below critical temperature of CO2. This may give unstable and/or wrong results. @Daniel: we should modify this like in Aspen - define a component beeing either as a Henry component or not.
Hi, please open simulation file "Electrolysis Cell with ExcelUO" from samples folder. Then you may read instruction to reconnect Excel file. This is necessary as the samples folder with Excel file is different at every installation of DWSIM. Press first button "Search" to find "Electrolysis.xlsx" file in samples folder of DWSIM. After connection press second button "Edit" to open file in Excel. You will find 3 tabs "Input", "Output" and "Calculations". You may not change structure of Input or Output...
Hi, as you probably know, gases like oxygen, nitrogen, hydrogen, ... are solving in liquids as well. This is depending on pressure and temperature. This is calculated with the Henry coefficient of such components. You will have to compare your calculated values with literature to verify the exact value. Gregor
Hi Nizar, Sure, this is possible. Did you already check the sample with an electrolysis cell? This sample was created by me some years ago when i implemented the Excel-UO to demonstrate usage of that UO. This is not a very highly sophisticated sample for an electrolysis yet, it rather was created for demonstration purpose of that UO. The exact values of your cell, like efficiency, U/I curve and so on still need to be checked and adjusted by you! If you have further questions, please move to DWSIM...
You may try property packages UNIQUAC or NRTL. You need to do a regressen of experimental data to get the required interaction parameters. I would be happy if you could supply the final simulation and regression files here in case of a success. Best Regards Gregor
Hi Felipe, this can be done in a very simple way. Just take a feed stream and run it through the compressor. As this is a continuous simulation you may transfer this to your batch operation by changing the flow units by removing the division by time in your mind. For instance: Feed with 1000 m³/h is compressed to 5 bar in DWSIM. You will find temperature and volume flow m³/h in output stream. Now you can interpret this as a batch process in following way that 1000 m³ of feed are compressed to 5 bar...
Hi, on SpreadsheetUO - Editor you will find a button "create new". This will create an empty Excel sheet from the template. With button "Edit" you can edit that table. There are tabs "Input" and "Output" inside that Excel file. Input tab will contain values from connected input streams. In Input tab you also can add some parameters which are displayed in DWSIM later. Results of your internal calculations are written to the Output tab. During calculation, DWSIM is writing values to the UO, calculating...
Please wait for the update. But you might use a workaround in meantime: Use a "Specification Block" to read energy stream of reactor and write it's negative value to energy stream of heater. The heater needs to work in mode "Energy stream"
Hi, this is right. A solution is already in progress. I already prepared a commit to GitHub to solve exactely this problem. https://github.com/DanWBR/dwsim6/pull/196 You will have to wait some days still as i need to update some files first. Gregor
Hi, this is right. A solution is already in progress. I already prepared a commit to GitHub to solve exactely this problem. You will have to wait some days still as i need to update some files first. Gregor
Please add your Component definition file here for inspection.
Hi, please check out the following link: https://dwsim.inforside.com.br/wiki/index.php?title=Using_the_Compound_Creator_Utility You should follow the following path: 1. Create new component with Component Creator utility 2. Enter as name "Glucose" and add CAS-Number 50-99-7 3. Import Data from Chemeo Database 4. Add Joback groups (These groups are not impoeted from Chemeo automatically yet) https://www.chemeo.com/cid/33-990-6/Glucose 5. Check for additionall informations on NIST-Webbook by clicking...
Hi Luca, i am the "inventor" of that behavior and this behaviour is "by design". Some years ago i wrote the code of that unit to handle a solid phase. The flash tank is used for separating liquid and vapour phases, but not for separating solid phases. Let's explain the idea behind that. Imagine a stream with one or two liquid phases, a solid and a vapour phase entering a flash tank in real live. The vapour phase is always leaving at the top and liquid phase at bottom. The flash tank is equipped with...
Hi, i modified the existing urea component to give realistic results for liquid density of solutions and a deminishing vapour pressure as a solute in water. But when you calculate solubility, the results are not even half of literature data. Therefore boiling points are not correct as well. @Daniel: I think we will need some kind of regression of interaction coefficients for NRTL/UNIQUAC models from solubility data.
Hi, first of all, you should use only a single flash algorithm -> Nested Loop (SVLLE) The same is for property package -> initially try Raoults Law (ideal, without interaction parameters). Now you should check solubility data of urea in water first! If you got that right, you may proceed to evaporation of that solution regards, Gregor
Try a sensitivity study Gregor
Hi Vincent, i am sorry, this can't work. Unifac groups are used to automatically generate the required Joback groups. But, as you noted, there is no Si in Joback model availabel. Therefore this will not work. The prefered procedure in this case would be to import this component from an external database (Chemeo or Cheric). But available parameters of this component are not sufficient. In this case, you will have to deliver all required parameters from other sources available to you (Literature, laboratory...
Hi Evan, you may try the Excel-Addin. First you may prepare a table, containing all criteria as separate rows. Then you add a table containing the TP-Flash calculation. Then you create a VBA-macro where you write the criteria from one row to the flash calculation sheet and recalculate the flash. Now you can copy the results back the the criteria sheet and advance to the next row. Gregor
Hi Benjamin, this is already possible. You need to select flash algorithm "NestedLoops SVLE - Eutectic". The other algorithm usually is not appilcable, depending on you system. Your component which is to be precipitaded needs a proper definition of the relevant pure component properties: Temperature of fusion Enthalpy of fusion * Heat capacity of solid and liquid Further details have a look into the code: https://github.com/DanWBR/dwsim4/blob/master/DWSIM.Thermodynamics/Flash%20Algorithms/NestedLoopsSLE.vb#L371...
Please attach your simulation for review. You can use UNIQUAC/NRTL/MODFAC (NIST)/MODFAC (Dortmund) as property package. You should compare the different PP's. I think the MODFAC-NIST probably will give the best results. You also need a suitable flash algorithm which is capable of VLLE calculations. I recommend "Nested Loops VLLE". Go to configuration an select both components as possible second liquid. Now this will work. Gregor
Define a stream with required composition. Then set specification either to "Temperature and vapour fraction TVF" or "Pressure and vapour fraction PVF". Define vapour fraction to 0 or 1. This will calculate the bubble / dew point. Gregor
As Daniel already wrote, you need to use a conversion reactor. Select "Define Outlet...
Definition of streams: select stream in editor window select basis: mass flow enter...
Hi Yogesh, some remarks to your solution: replace component air with components oxygen...
Hi i am testing your case just now. But i am still strugling with the first absorber...
Hi Yogesh, this project seems to be feasible with DWSIM. But it will not be a project...
Hi Jelle, there is even one more issue to consider with Gibbs reactor. This reactor...
Hi Nick, you need to use the conversion reactor. You have to add two reactions of...
Hi, as you already noticed, no group is available for that component. Neither in...
Hi Qiwei, why should temperature go up to 250°C? This is the dew/boiling point of...
Hi, the correct answer is: "it depends" My diagram depicts the end of evaporation...
Hi Qiwei, the answer is "thats thermodynamics". Please have a look to the VLE diagram....
Hi i modified your sample. I think this is what you want to calculate. Just run the...
I don't know the exacte definition of this standard but it looks like a boiling curve....
Hi Luca, there was a bug in actual implementation. This should be resolved with next...
Hi, sulfuric acid is not existing yet. You need to define a user component Grego...
Hi Josh, i tried your case with a mixture of water/ethanol and it worked without...
Hi Rasmus, i created a milk component with your data. This component has an extremely...
Hi, I think i can help you as i am doing similar simulations quite successfull -...
Hi, I think i can help you as i am doing similar simulations quite successfull -...
Hi Stefan, DWSIM is loading component data into memory on startup. If you add a new...
Hi Stefan, your assumption was right, parameter is not utilised in function E. You...
Hi Stefan, I would like to explain the working of regressions in a more detailed...
Hi Toby, the Gibbs reactor has two calculation modes. The mode you are using has...
Hi Hans, the pipe model has been reworked significantly by Daniel (DWSIM4). Your...
I already checked that a mixture of Glycerol and PPP are splitting into two liquid...
Hi Sabina, the biodiesel simulation you intend to do seems to be possible straight...
Hi Sabina, there are several different ways to accomplish that. Depending on the...
Hi Alba, you need to select the unit operation object and press F1 key. This will...
Hi Alba, it seems, you don't completely understand the working principal of this...
Hi Peter, i had a look into your simulation. There are several problems you introduced:...
Hi, did you read the help? I think your questions will be answered there. Generally...
Even if your immediate problem is solved, this is still regarded as a workaround...
The component Cyclohexane is available as a ChemSep component already. You need to...
Hi, there was/is a bug in calculating reactors. The internal calculation results...
Hi, please attache your simulation file to this thread for further inspection. G...
Hi Juan, i did a check of the utilised property package. You may use either NRTL,...
Hi Juan, i did a check of the utilised property package. You may uses either NRTL,...
Hi Alba, i guess you want to use an electroyle property package? If this is the case,...
Hi Kevin, there is no such option! If you want to calculate the solubility of hydrocarbons...
Hi, i guess, this will not be possible. DWSIM is a static state simulator, where...
Hi Gökhan, it seems, you missed to set the "Adjust simultaneous" option in parameters...
Hi Gökhan, I tried "Modified Unifac (NIST)" with Nested Loops VLLE as property package....
Hi Alba, there is another property package for electrolytes "Extendet UNIQUAC" which...
Hi Thomas, you will find this parameter in section 2 "Pressure downstream". I prepared...
Hi Thomas, you will find this parameter in section 2 "Pressure downstream". I prepared...
Hi Thomas, the outlel pressures is defined by the operation mode of the mixer. You...
Icons for Mixer and Splitter were replaced.
Icons do not match
I quickly created a sample where ethanol and methanol is extracted from water by...
Hi Aditi, i modified the Excel table and the simulation in order to integrate the...
You don't need to add this catalyst as a component to the simulation. If you would...
Hi Aditi, as promised, i created a preliminary model for you. You will see a membrane...
Hi Aditi, as promised, i created a preliminary model for you. You will see a membrane...
Hi Aditi, give me a while and i will come up with an improved model, which should...
Hi Aditi, this process layout is a little differnt to the model I sent to you. We...
Hi Aditi, I had a look into your simulation files. I really wonder if such a reaction...
Hi Aditi, I had a look into your simulation files. I really wonder if such a reaction...
Hi Aditi, I had a look into your simulation files. I really wonder if such a reaction...
Hi Aditi, did you already read the help? What exactely you didn't understand? First...
This sample demonstrates the usage of an Excel-Unit-Operation which is used to create...
Hi JMB, i created a new algorithm which is able to handle even very nasty cases like...
Hi JMB, it took a while, but as i promised, I developed a new algorithm for that...
Hi, i had a look into this algorithm and identified the root cause of the problem....