Process Simulation Essentials for  Undergraduate Education Attend our exhibitor workshop at the 2015 AIChE Annual Meeting

 

Calling all Chemical Engineering academics! Are you or your colleagues attending the 2015 AIChE Annual Meeting in Salt Lake City this November? If so, you won't want to miss out on Chemstations' exhibitor workshop called Process Simulation Essentials for Undergraduate Education. Professors in Chemical Engineering departments worldwide have communicated to us for many years that they want to teach "engineering" and not "process simulator usage." Students need to understand the tools they will use in industry, and have an interest in a well-rounded resume/CV. So in response, we've put together a library of materials suitable for use in academic curricula.   Chemstations would like to invite professors, students, and all other interested parties to learn more about our new Process Simulation Essentials for Undergraduate Education program. We will present a half-hour overview (repeated three times during the session period) of the materials available to professors and students, including example simulations, recorded videos, presentation slide decks, and even a worldwide student competition. Between our formal presentations, Chemstations staff will be available to answer questions and go into more detail on all of the available resources.   2015 AIChE Annual Meeting - Salt Lake City, Utah Salt Palace Convention Center, Room 255C Monday, November 9, 2015 12:30 - 3:00 PM   Stop by and learn what our program offers: Process Simulation Essentials - for Undergraduate Education PowerPoint slides for instructor use Slide notes included for suggested talking points Use all or only those you choose YouTube presentations including: 1-hour introduction specifically for student audience Short How-To Demos on commonly used features 6 other 1-hour segments covering select topics in more detail Simulation example files with notes Divided into topics following typical ChemE curriculum Automatically installed with CHEMCAD PDF version available for review outside of program Student Challenge Problem - Process Simulation Cup Student opportunity to work on real-world simulation problem Compete with students from around the world Further Learning Recommendations Websites to direct students with questions Articles and books Easy Licensing Network licensing allows access from any student computer connecting to university computing networks Full program capabilities, thermo models, and physical property database Reduce your teaching workload and empower your students: Stop hearing "I couldn't get into the computer lab" as an excuse for incomplete assignments Focus your time on developing course material instead of teaching simulator use Get students up to speed on simulation tool faster Expand students' real-world skills and interaction with global network   There is no cost to attend for AIChE Annual Meeting registrants. The overviews will be presented at 12:45 PM, 1:30 PM, and 2:15 PM. Come by for a presentation, learn about the available resources, and chat with other educators and our staff. Please spread the word by forwarding this message to any Chemical Engineering professors or students who may be attending the Annual Meeting. For questions, or to learn more (especially those not attending), please contact Jill Eastwood at jille@chemstations.com.

 

Time to vote in the 2015 AIChE election!

Are you a member of AIChE? If so, you can help decide who will be the next leaders of the Institute, by voting in this year's Board of Directors election.

Voting has already begun! To learn more, view the candidates' statements, and vote online, you can click here.

Voting ends October 12 at 11:59 PM EST. Click on over and make your voice heard!

Did you know CHEMCAD can be used for environmental point-source emission calculations?

At some point in the design or operation of chemical processes, you may need to satisfy regulatory compliance by doing emission calculations. Rather than use separate (possibly non-rigorous) tools, we’d encourage you to use the CHEMCAD models you may have already built for your processes.

Our good friend, Dr. Jeff Silverstein, has written a thoroughly-referenced paper that walks through two examples of charging empty vessels based on the US EPA’s publication: Methods for Estimating Air Emissions from Chemical Manufacturing from Volume II: Chapter 16 of its Emission Inventory Improvement Program (EIIP).

Click here to download the paper, and here to download the CHEMCAD example simulation files referenced in the paper.

Please have a look to see if you can take advantage of his long experience in the field to speed up and improve your environmental compliance calculations. We, and Dr. Silverstein, welcome your feedback for potential future papers in this area.

Did you know that CHEMCAD can calculate flow rate as a function of pressure?

How do you approach engineering challenges involving hydraulic balance in piping networks? The right tools are essential when designing and evaluating a flare network or relief piping system, calculating flow and pressure drop through equipment, or diagnosing leak problems in plants.

CHEMCAD can help with these challenges, by performing hydraulic balance and pressure calculations in piping networks. The program predicts pressure drop, flow rate as a function of pressure, choked flow, and backflow; for more complex systems, the program also calculates pressures and flow distribution through different branches in pipelines based on pressure balance.

If enough variables are specified in the simulation, CHEMCAD can simultaneously calculate the unknown pressures and/or flow rates throughout the model.

CHEMCAD also leads users to specify the geometry in pumps, valves, compressors, and fittings, and hydraulic resistances in pipes, to enable estimation of the pressure balance as a function of the known variables.

The back pressure on valves, pipes, and pumps affects pipelines’ upstream and downstream conditions. Reverse flow can damage equipment, contaminate fluids, and present a serious risk to health and safety. CHEMCAD can predict flow direction, backflow, or reverse flow by simultaneously solving the pressure balance throughout the entire piping network; it also calculates the flow that pumps and compressors can handle using inlet pressures, outlet pressures, and performance curves.

If you’re ready to start setting up piping networks in CHEMCAD, contact your sales or support representative for more information.

Did you know you can model mass transfer in distillation columns in CHEMCAD?

Distillation columns are the ubiquitous workhorses of the chemical processing industry. Design and optimization of these unit operations is done at a much higher level of fidelity than ever before using mass transfer models.

As students, we learned McCabe-Thiele diagrams and shortcut methods to solve simple distillation systems. Often, a little more complexity was added using a spreadsheet to solve harder problems. Then, of course, we were given access to a simulation program which used more rigorous methods, including simultaneous correction and/or inside-out algorithms. When it came to actual columns in the field, however, they didn't always achieve quite what the equilibrium-stage based calculations predicted. You could specify an overall efficiency or even stage-by-stage efficiency profiles to get a better match, but this was a crude way of dealing with the issue.

Enter mass-transfer models, like Bravo & Fair for random packing, Bravo, Rocha & Fair for structured packing, and Billet & Schultes for random or structured packing. CHEMCAD includes these models, along with a database of common packing coefficients. For trayed columns, we include the Chan-Fair, AIChE, and Zuiderweg tray models.

Defining the geometry of such a column requires more user input, but the payoff is vastly improved accuracy and realism in the results for product streams, energy usage, and pressure drop.*

So, take a moment to back up a copy of a simulation with distillation column(s); convert them to mass-transfer by specifying the actual trays/packing you're using; and enjoy the benefits of more accurate answers to your distillation calculations. If you have questions, or if you want to share your successes, give our technical staff a call today!


* I should mention here that from what I've seen in papers delivered by distillation experts over the years, column-internals installation issues can cause significant deviation from expected results in the field. There are a number of companies that specialize in identifying such issues, and I invite you to check out our friends, Dr. Frank Seibert & Dr. Bruce Eldridge, over at the University of Texas Separations Research Program if you're interested in applied research on this topic and more.

Did you know you can quickly make property calculations in CHEMCAD?

Quick, what's the bubble point of the process stream entering one of your columns? What's the viscosity of the stream entering your heat exchanger? You may find yourself needing answers to these types of questions much more often than needing to model an entire process, and we've made it easy to access these calculations in CHEMCAD.

If you have an existing flowsheet with a stream already set up with the right composition, just double-click the stream, and you can immediately calculate bubble/dew point (T or P) or vapor fractions. Just remember Gibbs' phase rule and specify two of the three available fields (T, P, VF); then click the Flash button and you'll have your answer. To get at the thermophysical properties, just right-click the stream and select View Properties to get a quick report.

But what if you want to use a composition that isn't in your current flowsheet? If all the right chemicals are in your component list, and you've got the appropriate K-value and enthalpy methods selected, try this trick: 

1. Make sure no streams are selected (you can click in the white space of the flowsheet to be certain).
2. On the CHEMCAD main menu, choose Specifications > Select Streams.
3. In the input dialog, type a stream number not currently used in your flowsheet (like 999) and click OK.

You'll now be working with a 'dummy stream.' You can specify stream conditions and compositions, but nothing you do here will affect any of your actual flowsheet streams. By clicking Report > Stream Properties > Select Streams and entering that dummy stream number, you can even generate thermophysical property reports. The dummy stream will be accessible for as long as you have that flowsheet open (it's cleared from memory if you switch flowsheets or close CHEMCAD).

Don't let your investment in simulation sit around waiting for the large projects! CHEMCAD is like having your own chemical engineering calculator, and it's ready to supercharge all of your tasks.

Whether you're working on a simulation of your entire process, sizing a few pieces of equipment, or just looking for a quick property calculation, don't hesitate to get in touch with our technical staff for more best-practices tips.

Do we need more chemical engineers? Do we need more heroes?

Someone recently forwarded me a link to ExxonMobil's perspectives blog on the subject of engineers in the United States. You can take a look here to see Ken Cohen's take on addressing the need to educate and connect with young people about engineering and engineers--especially the societal impact, both past and present, of our profession.

As I pointed out several years ago, there are a couple of ways to attack this problem. ExxonMobil's site, BeAnEngineer, and their associated television commercials are a fantastic 'top-down' approach to get the message out to the general public. The complementary approach is 'bottom-up,' and their material is also a great resource for engineers who want to arm themselves with facts and figures they can use to have one-to-one or one-to-few conversations with young people or non-technical colleagues and acquaintances.

If we, as engineers, don't tell our story and tell it well, then we leave ourselves open to two serious consequences: (1) our story gets told by those who view chemicals and chemical engineering as inherently 'bad,' and (2) fewer young people are interested in pursuing chemical engineering.

You know the role we play in society now, and the role we'll play in the future. Learn more about our past successes. Tell your story. Tell our story. Be a hero.