Thursday, October 31, 2013

Happy Halloween! (a hint at CHEMCAD version 7.0)

Aaron, our resident mad scientist, hard at work on version 7.0!

Great news: we're in limited beta testing for the new version.  Our focus has been the flowsheeting tools (symbols, streams, look and feel), and you'll still see a number of engineering improvements (a gas membrane UnitOp is coming, for example).  We are incorporating a much more modern toolset with an eye toward (1) fitting in with other drawing/flowsheeting tools standards, and (2) addressing the 6 years of feedback from the 6.X versions. Nothing too scary, so stay tuned here for more information.

Tuesday, October 29, 2013

Competitive Comparison - A Rebuttal

Quick summary:  Recently, a document being circulated by our competitors purporting to compare CHEMCAD to Aspen Plus came to my attention. I'm going to address the document in general, and then correct some of the misinformation contained in the document. If you are in the market for a chemical process simulator, or thinking about switching, read on:

I suppose we should feel flattered that our competitors feel it necessary to address us directly in the marketplace, and I do understand the need for comparison. Often customers ask us, "What's the difference between CHEMCAD and the others?" Here's the bottom line: rarely, if ever, will one simulator company know enough about the others to offer a truly useful comparison, and it would be expecting too much to believe that you're getting an unbiased comparison.

If you want to compare, don't hesitate to ask for a comparison, but do your own evaluation by asking for a trial license.  I can't stress that enough. Use the trials to simulate your processes with any and all software packages you're considering. Test drive the customer support facilities. Call the hotlines. Send emails. Search the customer portals. Yes, it will take longer than asking the sales groups at each competitor to compare themselves, but it's critical and time well spent.

So, here's the document:

"~14,000 (without support)
Also sells an hourly usage rate of $15-25/hr in some geographies"
Jumping right into the CHEMCAD side of things: CHEMCAD is a suite of several modules (see here), so this price appears cherry-picked to be close to a 1-year commitment for just our CC-STEADY STATE module. Longer commitments and prepaying can significantly discount that amount. Oh, and support (and upgrades) are included in our license fees. We do offer multi-year, yearly, monthly, and even hourly options. Again, any price comparison ought to be done using the specific modules and licensing terms you want. Contact us- it's a painless process to have our teams come up with a price for you.

"840 Customers
3.3% Market Share"
We do have over 800 active organizations using the software, however, this comparison is a bit misleading.  For our industrial customers, a single license is shared by an average of 5-6 users. At academic institutions, there may be as many as 200 users. Yes, our competitors dominate the largest CPI organizations, and we too have licenses at many of those same organizations on the desktops of engineers who prefer our products.  According to Aspen Technology's most recent annual report, they claim 1,750 customers. Regarding market share, I'm not sure what to make of these numbers. What I can say is that Chemstations had approximately $7M in revenue for the 12 months ending Sept 30, 2013. They have a lot more. If that's a metric you want to use in your decision making, just make sure you understand that Chemstations only does simulation software. It's our passion, and it's our focus.

Physical Properties
"2000 or so 'standard components' (DIPPR database)"
We are a licensed DIPPR distributor, and we offer over 2,200 components to our users. In addition, we have over 10,000 binary interaction pairs for a variety of our thermodynamic options. However, I would again like to point out the importance of trying out the software(s) to see if your chemical components are available. Talking about 2,200 or 24,000 components isn't relevant if (1) both software packages have your components, (2) neither package has them, or (3) the data is sparse and/or inaccurate.

User Interface
"Microsoft 2003-style User Environment"
I'm not sure what "Microsoft 2003-style" is, and I'm not sure it means the same thing to all people. Our interface is currently undergoing a complete overhaul (watch for a coming blog post about version 7.0!), but the 6.X versions were built using a very involved process of face-to-face interviews with a cross section of our user base to identify core workflows. And it's built with 25 years of history and our reputation for ease of use. I'm sounding like a broken record, but you ought to put this to the test with a trial.

Customer Support & Training
"Personal user support, not available 24/7
3 or 4 Workshops held a year
3 or 4 daylong 'CHEMCAD Essential' online workshops available every year"
Again, I don't know what "personal user support" is, so I'll describe our system. We have trained engineers, who are CHEMCAD experts, available by phone and email throughout the business day in both Houston, TX, USA and Berlin, Germany. We provide a customer portal which tracks customer support tickets and allows you to follow the progress of any issues requiring a high level of interaction (file exchange, etc.) and a knowlegebase of common support issues. We do provide workshops around the US, webinars throughout the year, and importantly, we offer on-site training. Finally, our 'Essentials' videos are available on demand at our YouTube channel.

"Link between CHEMCAD and excel is complex and difficult to use"
Put our Excel Data Map to the test. It's very powerful and you can create a lot of value with it. If you think it's "complex and difficult to use," don't hesitate to tell us. Here is a recent paper which includes an application of our Data Map.

"CHEMCAD uses sequential modeling so it doesn't scale up well"
We use a sequential modular solver by default, and we offer a simultaneous modular solver. Scale-up to large numbers of unit operations, in steady state or dynamics, is not an issue. Here is a paper detailing a very large, dynamic model where CHEMCAD "scaled up well." And while we are on the topic of "modeling," we can also do a momentum (pressure) balance across the flowsheet at the same time we are doing the heat- and material- balances.

"Some solids handling, limited properties for solids"
We have particle size distribution calculation, solids unit operations, and you can declare any component in your flowsheets as a solid to remove it from phase equilibrium calculations. Solid properties for many components come from DIPPR, and we also provide solid-liquid equilibrium (SLE) calculations.

"Batch capability with CHEMCAD Batch"
CC-BATCH is a batch distillation specific application. With our CC-DYNAMICS module, you can model dynamic, batch, and semi-batch processes (including tank reactors with reaction kinetics and heat transfer calculations with a jacket, a coil, or both).

"Standard distillation columns"
We provide equilibrium stage SCDS and Inside-out (TOWR) unit operations. We have reactive distillation within the SCDS. We also have mass-transfer-based models for trays, random packing, and structured packing. We can run these in steady state or dynamics (including dry startup and shutdown).  Oh, and we have incorporated "years of feedback and ideas" also. Twenty five years as of 2013, if you're counting.

"Very limited equipment costing available; not proven in the market and not trusted by users"
Equipment costing is not our business. We provide a tool which does a good job of relative costing (one process versus another).  We do not sell on the idea that we provide accurate, absolute costing. We do provide a variety of unit operation sizing algorithms that can be sent to rigorous costing packages or to equipment vendors. Finally, the code for our costing is user-accessible, so you can edit it directly and use your costing code.

"CC-Dynamics available"
CC-DYNAMICS, our dynamic process simulation module, is available as an add-on to CC-STEADY STATE or as a standalone package.

Heat Exchangers
"CC-THERM available for add-on and standalone"
CC-THERM, our heat exchanger rating and design tool, is available as an add-on to CC-STEADY STATE or as a standalone package. You can even run a flowsheet using the actual performance predicted by the geometry of the exchanger for a more rigorous simulation (we call this "simulation mode").

"No Equivalent software available"
We don't have software that makes any attempt to automatically optimize energy use. We provide an optimization routine (which can handle integer values), and we use a variety of software protocols (OLE, COM, OPC, CAPE-OPEN) if you would like to connect an external optimizer.

We have a large number of customers in the biofuels business, from folks who design the facilities to those who operate them. Test drive us if you want to see whether your process is supported (I'd bet it is).

To sum up- it's best to take a comparison written by a vendor (even us!) with a large grain of salt. For a true comparison, ask for a trial. Use customer support. Ask for, and call, references. We certainly want your business, and we want to help you create value for your organization.

Thanks for reading,

Steve Brown
Chemstations, Inc. 

Friday, August 10, 2012

The greatest (chemical industry) show on Earth!

Have you ever visited a European city on the river with 167,000 members of industry and academia?

Welcome to ACHEMA! Every three years the city of Frankfurt hosts this week-long chemical industry show, which is so large it has its own daily newspaper. The show boasts more than 1,000 exhibitors, spread among several exhibit halls--most of which have three floors of exhibits.

Several members of the Chemstations team spent the week visiting customers, prospects, and colleagues at our booth in exhibit hall 9.

Chemstations Europe has been coordinating our presence at ACHEMA for many years. We enjoyed the opportunity to visit with our European staff, talk with existing customers, and meet with prospects. We demonstrated electrolyte flowsheets, custom rate expressions for kinetic reactor models, rigorous heat exchangers--in fact, in those five days we demonstrated most of the features of CHEMCAD to visitors who wanted to know, "Can CHEMCAD do this?"

It's common for university classes to tour the exhibit as a group; having twenty students and a professor 'stop by' for a quick demonstration is always interesting!

The culture of ACHEMA is exciting. You can't see the entire exhibition, as it's simply too large. Some vendors will have artistic displays, some have projectors, while others have functional equipment. I once saw a stainless steel forklift in the hall, with a sign that proclaimed "Entire unit can be sterilized" in several languages. Some exhibitors will even have operational process equipment in their booths.

You'll see fun attempts to lure visitors to booths, such as "free foot massage in this booth." At the end of the day, many exhibitors will start serving alcohol and snacks to their visitors and neighbors. During the week there are receptions and dinners related to the event, and several restaurants and halls that stay open late, serving excellent German beer. When you leave Frankfurt, you will remember this event for the rest of your life.

Many of the exhibitors recognize each other from previous shows; several exhibitors have the same location and neighbors in the hall. Our booth was next to Infraserv Knapsack, a longtime CHEMCAD user. They'll be co-hosting the 3rd Symposium on Computer Aided Process Optimization in Germany, February 2013 (more information).

The next ACHEMA takes place in spring of 2015, and we hope you'll stop by our booth and say hello! Of course you can also see us at other meetings, such as the AIChE Spring and National meetings each year.

Friday, February 17, 2012

Books you should own if you read this blog

Since childhood, I have been a voracious reader. In my youth I would typically read six books at the same time, during school. I'm always excited when I visit a bookstore, browse Amazon, or see a flyer for new books. At the AIChE spring and national show, I always spend time at the exhibition visiting the booksellers.

Newspapers and talk show hosts tell us which books we should read because everyone else likes them; finding good books that are relevant to chemical engineering takes a bit more searching than the metro page. I'd like to share a list of books--technical and non-technical--which I think should be read by anyone who uses CHEMCAD.

Portrait of a Chemical Engineer (As a Young Man Growing Older), by Ben Horwitz

I've had the pleasure of knowing the author for years. He's a brilliant man, and a great engineer. Horwitz follows his career from his first engineering job through time as head of engineering at a global engineering firm, and concludes during the early period of his independent consultancy. Few of us will have such a varied experience in process. Currently the book is available only from the author at his web site ( Volunteers (such as myself) will likely help convert it to Kindle format. If I were dean of a chemical engineering department, I would recommend this book to all prospective students.

Chemical Engineering in Practice--Design, Simulation, and Implementation, by John Edwards

I've been lucky enough to work with John for nearly a decade. He has vast experience in applied controls and engineering, and runs a successful engineering company. This book teaches what he feels are important concepts of applied engineering. We're flattered that he uses CHEMCAD simulations for so much of this book. If you have young engineers working in process design or modeling (or controls, or anything vaguely related to process design), I would recommend this book. Available in print from the author's web site (, or in Kindle format from Amazon.

Chemical Thermodynamics: for Process Simulation, by J. Gmehling, et al.

I'm recommending a book that I haven't even read! Gmehling is a world-renowned expert on physical properties and thermodynamics. I expect this to be a valuable reference to anyone who uses a process simulator. This book has just been released, and my copy is on order. While I haven't read the book, the reputation of the authors is enough for me to recommend it. I've known Gmehling for years; I'm confident this will be a good book. Published by Wiley, available from various resellers or directly from the publisher.

Branan's Rules of Thumb for Chemical Engineers, by Carl Branan

Ever need to guess an important number? Branan has done it already. His book gives you practical advice on how to solve many problems, and also decent guesses for numbers such as "heat transfer coefficient for this utility and this process type flow."

The Properties of Gases and Liquids, by Poling, et al.

Want to understand how simulators predict physical properties? Want to do a better job predicting properties for new chemicals that you add to a simulator? Read this book.

Product and Process Design Principles: Synthesis, Analysis and Design, by Seider, et al.
Analysis, Synthesis, and Design of Chemical Processes, by Turton, Whiting, et al.

Either of these books would be useful for a design class, or for engineers who want to teach themselves more about modeling processes with a simulator. The named authors are CHEMCAD users. We keep several copies of both books in our office.

Refinery Process Modeling, by Gerald L. Kaes

Want to learn how to model refinery operations with a process simulator? Start with this book. Kaes talks about the bases of methods that are in your simulator, such as creation of pseudocomponents from a distillation curve. He explains refinery terms (e.g., the difference between kerosene and naphtha), and discusses modeling concerns for various equipment. Good for engineers that need to learn about refining, how to model refining operations, or both.

Phase Equilibria in Chemical Engineering, by Stanley M. Walas

Want to get into the nitty-gritty math of applied thermodynamic vapor-liquid equilibria calculations? This is the book for you. It's out of print, and it's hard to find. If you have access to a copy, I would recommend that you skim through it to determine whether this is 'too technical' for you. If you don't have access to a copy, then Gmehling's book might be a better starting point, simply because it's readily available in print. If you have a spare copy of Walas' book that you'd like to sell, drop me a note.

Monday, November 7, 2011

An interesting presentation at 2011 AIChE National meeting

I’m privileged to be able to regularly attend the AIChE Spring and National (fall) meetings. I attend presentations, meet with customers and prospects, and attend division dinners. Chemstations has been a long-time exhibitor at these meetings, and often sponsors the meeting. I’m vice-chair of the admin committee for DIPPR (, which often meets during the National meeting.

One of my favorite papers at the 2011 National meeting in Minneapolis was a presentation by Dr. Becky Toghiani titled Group Contribution Methods in Undergraduate Chemical Engineering Thermodynamics. Dr Toghiani is a professor at Mississippi State; we’ve known her for years and admired the way she teaches her students the fundamentals. In her presentation, Dr Toghiani discussed one way she has her students use computer programs (CHEMCAD and Cranium*) to learn about the limitations of predicting chemical properties.

Several of the exercises involve predicting well-known chemicals and comparing the results to database values. The students start by comparing predicted pure component properties to experimental data, noticing that if Tc, Pc, and Tb are not well predicted, other properties that are correlated from these values (VP, Cp, HOV) will not be well predicted either. This shows students some of the limits of correlations.

The students then move on to mixture behavior, where they model the separation of binary mixtures using UNIFAC to predict non-ideal VLE. After modeling with predicted chemicals, they look at experimental VLE data to see how well the predicted behavior matches the system. One of the systems is a mixture of o-xylene and p-xylene. Use of a first-order subgroup model (such as Joback) to predict these chemicals will lead to these predicted isomers having the same properties and UNIFAC subgroups, which means they cannot be separated. Use of a second, order model will create slight differences in critical properties and allow for (very difficult!) separation. Naturally, the students are not warned that “cannot be separated” is the wrong answer; this is a process to help them learn to think.

These problems teach Dr Toghiani's students to remember “what is behind the curtain” when they are using modern tools and methods. The students also learn to inspect and think about their results, and ask “Should I try to approach this problem in a different way?” These are the types of lessons we really like; they show the power of a process simulator, and they also teach that a simulator is a tool, not a magical device. It’s important to understand the engineering concepts and the models underneath, even if you don’t have to do the math yourself.

* I should note that I was sitting next to a long-time friend of Chemstations during this presentation: Dr. Kevin Joback, President of Molknow ( and author of Cranium.

Monday, March 21, 2011

Chemical Engineering Hero: Ben Horwitz

You’ve probably caught on to the fact that we here at Chemstations are pretty proud of the chemical engineering profession. Well, I’d like to take this opportunity to recognize someone who has made some serious contributions to chemical engineering practice everywhere he’s been.

Those of you who have met Ben Horwitz know that he’s one of a kind. He’s sort of a force of nature that sweeps in and makes an impression. I’ve worked with Ben since 1995, and I owe a lot of what I know about practical process engineering to him.

Ben made a career at HK Ferguson (and then MK Ferguson) before going out on his own. He’s designed, troubleshot, de-bottlenecked, and optimized more processes that most of us will ever see; his hands-on, in-the-field techniques have made plants run when others had given up. In my experience, he doesn’t brag about the financial impact of his efforts, but I’d wager that he’s easily saved millions of dollars for his clients. Along the way, he’s educated future engineers in college process design classes and trained hundreds of engineers (and chemists!) in the use of simulation tools with his irreverent yet effective style. Ben is NOT a “click here” and “click there” instructor (as you know if you’ve taken a class!); he is a problem solver of the highest order, and he never lets you forget that process engineering is about solving problems.

If you’re interested in learning more about Ben and his myriad of engineering (and life) experiences, I invite you to take a look at his web site ( You will very likely find his book, Portrait of a Chemical Engineer, to be a fascinating read. It spans his university years, his time in the Peace Corps, and through to his professional work; it’s told in a fast pace through a series of vignettes that capture the highlights of the events that molded and shaped him into the professional, the chemical engineer, and the hero that we’ve come to know. You can read an excerpt online, and even order your own copy.

I’m incredibly lucky to count Ben as a colleague, and I’m proud to count him as a friend.

OK, so if you’ve read this far, I’m going to tell you about Ben’s influence on me. 1994. I was pretty green (ok, very green) and just out of undergrad when Ben began teaching at our seminars. I think the first thing he said to me was, “Who are you?” I said I was the new guy; he looked me up and down and walked away. He spoke quickly. He was to the point. I had no bona fides yet, and I was unproven. I sat in the back of the seminar room and watched in amazement as Ben began by telling stories. Telling stories to teach simulation? This was an amazing sight, to be sure.

So there he is, telling stories. Setting up scenes in chemical plants. Describing characters. Replicating dialogue from other engineers, from plant managers, and from operations staff. Focusing our attention on the challenge at hand. And then he led us all down the chemical engineering, problem solving path. He often asked questions of the attendees—questions that forced us to think and really got to the heart of the challenges. He also gave quizzes. He used a flip chart to describe a problem, and he just let the class run with potential solutions. I don’t remember which quiz it was, or which day it was, but I do remember that I answered one of the quizzes in a way that caused Ben to leap up and say “YES! THAT’S RIGHT! STEVE IS EXACTLY RIGHT!” In that instant, I saw how passionate this guy was about both the challenge of process engineering and the objective of teaching its principles to the class. He cared more than anyone I have ever seen in the chemical engineering world, and with that answer, I was suddenly on Ben’s radar.

We probably worked together five or six times a year for several years after that, and I was always impressed by Ben’s ability to quickly learn every attendee’s name and background. Ben’s style is to engage everyone, keep your attention, and make it fun. He puts every ounce of his energy into the courses, and everyone comes out tired, but with new perspectives.

I don’t get to work directly with Ben as much these days, but when I get the chance I love to wander into our training room and see the class react to Ben’s stories. I know most of them by heart now, but they still sound as fresh and important as they ever did. This is because he loves what he does (and does what he loves), and that makes him a hero to me and the rest of us at Chemstations.

Wednesday, January 19, 2011

Great article on Heat Integration in CEP

The December 2010 issue of CEP (Chemical Engineering Progress) has a good article on heat integration. Disclaimer, I am a friend of the author (Alan Rossiter). Rossiter's article is a very understandable explanation of pinch analysis, a topic that is confusing to the uninitiated.

The concept of pinch analysis is that you don't need to use steam for all your heating needs, or cooling water for all your cooling needs. You might have 'hot' process streams that need to be cooled, and 'cold' process streams that need to be heated. Pinch analysis suggests that you will save energy if you use the 'cold' process stream as a utility for the 'hot' process stream, rather than purchasing steam and cooling water. While that may sound simple…most people find the next steps, performing the pinch analysis, difficult to understand.

Rossiter does a wonderful job showing us how to perform pinch analysis, and shows that the use of this method is not as difficult as we think. He explains how to understand the composite curve for 'heat sinks' and 'heat sources. He shows how you can perform a retrofit study, to see the potential benefits to integrating heat on an existing crude column.

Some of our customers have done pinch analysis before, some are interested in it.

Want to do it in CHEMCAD? We have the ability to generate a composite curve (fig 1, in Rossiter's article). You can specify the value for deltaTmin, the distance between the hot and cold curves. You can specify that some of the streams on the flowsheet should be ignored when you generate the composite curve; you wouldn't want to include a steam flow rate on the theoretical composite curve. When you're ready to explore alternate configurations, draw out a flowsheet with heat exchangers and match streams (Fig 3, Rossiter). We don't automatically match streams for you; we feel that an engineer needs to make that decision.

I suggest that anyone involved with utilities (or crude columns) and process simulators take the time to read Rossiter's article; it might give you money saving ideas.

PS While you are looking at recent issues of CEP, you could also take a look at page 59 of the Nov '10 issue, for a picture of the CHEMCAD Technical support team at AIChE's Process Technology Conference. Better yet, check out the back cover of January '11 CEP.