Chemical Engineering Practice

Analyzing APC Performance

August
2002
Instrumentation
To reap the most benefit from an advanced process control (APC) system, users need to know how to analyze and monitor the APC's performance.

How to Scale-Up Mixing Processes in Non-Newtonian Fluids

May
2003
Fluids and Solids Handling
Christopher Henry , Robert J. Wilkens,  Lew E. Gates
This article will describe the relationships that must be understood to scale-up fluid mixing processes in non-Newtonian, power-law fluids. The principles described apply to both close-clearance impellers, such as anchors and helixes, and to open...

What’s the Price of Steam?

July
2005
Heat Transfer
Petar Varbanov , Robin Smith
Realistic steam prices are necessary for the efficient operation of a chemical production site, both to allocate realistic costs to the different businesses on the site and to provide a true economic incentive for energy conservation.

Reshaping the Structure of Fluidized Beds

July
2009
Fluids and Solids Handling
J. Ruud van Ommen, John Nijenhuis, Marc-Olivier Coppens
Adding structure to a gas-solid fluidized-bed reactor changes the system’s hydrodynamics and can improve performance.

Selecting Nickel Alloys for Corrosive Applications

May
2007
Materials
Paul Crook
Nickel and its alloys offer resistance to attack by a wide range of chemicals, including acids, alkalis and salts, making these materials suitable for may CPI applications.

Process Control for Microreactors

August
2001
Instrumentation
Don  Humbert, Lech  Znamirowski, Olgierd A. Palusinski, Sarma Vrudhula
Field-programmable analog arrays coupled with microreactor technology promise to change the way plants are built, as well as the methods by which their processes are designed and controlled.

Keys to Bioreactor Selection

March
2002
Reactions and Separations
John A. Williams
A few basic types of bioreactor designs are used to produce a wide range of products, from antibiotics to foods to fuels. Here's how to pick the best options for your application.

Navigate Phase Equilibria via Residue Curve Maps

November
2002
Reactions and Separations
George J. Koplos, Raymond N. French, Waldo E. de Villiers
These maps provide a rapid, graphical means to visualize the separation possibilities and constraints of azeotropic ternary systems. They also help check the soundness of models used to predict equilibrium data.

Efficiently Solve Complex Calculations

October
2003
Information Technology
Mordechai Shacham, Neima Brauner ,  Michael B. Cutlip
Reduce the chances of computational errors by following this technique, which combines the use of a standard spreadsheet with a numerical software package.

Optimizing Batch Operations

January
2006
Reactions and Separations
Kah Loong Choong, Robin Smith
Use this novel method to optimize the operating conditions as they vary through time in batch processes.

Tools to Model Multiphase Separation

June
2007
Fluids and Solids Handling
David Connolly, Saeid Mokhatab, Timothy Newton
The flow fields in multiphase separators are often extremely complicated, making it difficult to model such systems. Computational fluid dynamics (CFD) and visual dynamic modeling (VDM) can be used together to overcome some of the challenges.

Selecting a Heat Exchanger Shell

June
2011
Back To Basics
Thomas G. Lestina, P.E.
The first step in specifying a shell-and-tube heat exchanger is choosing the right shell to meet process requirements.

Propel Your Pneumatic Conveying System to Higher Efficiency

April
2001
Fluids and Solids Handling
Francisco  Cabrejos, Herman  Purutyan, Thomas G. Troxel
For new and existing installations, there are many system and component choices available. Here’s how to narrow down the options to make the appropriate selection for optimal performance.

Pervaporation Comes of Age

October
2001
Reactions and Separations
Nick Wynn
This membrane process has found growing use for dehydrating organics. Uses keep increasing, mostly due to development of new, high-temperature membranes.

Put More Punch Into Catalytic Reactors

March
2003
Reactions and Separations
Ed Fontes, Olof Hernell, Phil Byrne
Using equation-based modeling to design these reactors can optimize their efficiency and throughput.

Team Up with a Consultant for Process Equipment Selection

August
2006
Career Catalyst
Gregory T. Benz
Engineers who specify, scale up or purchase process equipment typically have fewer internal or vendor resources available than in the past. This article explores the problem and offers a solution.

Selecting Agitator Seals for Bioprocessing Applications

January
2008
Fluids and Solids Handling
Gregory T. Benz, William Ho Liam Teng
Issues such as sterility, isolation and contamination must be considered when choosing seals for use in biotech and pharmaceutical processes. This overview describes common types of seals and offers guidance on selecting the appropriate seal for...

Realizing the Promise of Wireless

May
2009
Instrumentation
Bob Karschnia, Peter Zornio
Innovation drives the growth of wireless technology, as successful applications demonstrate cost savings, reliability, safety, and ease of use.

Produce Reliable Models with Efficient Meshing

August
2010
Computational Methods
Christian Wollblad, Ed Fontes, Henrik von Schenck, Phil Byrne
Improve your modeling skills to construct accurate, effective meshes that simulate or optimize a process in less time.

Tune Control Loops for Minimum Variability

January
2002
Instrumentation
Lanny A. Robbins
The Robbins tuning rules can reduce the variability of control loop response to about 60% of that observed with Ziegler-Nichols tuning rules.

Guidelines for Crystallizer Selection and Operation

October
2004
Reactions and Separations
Wayne Genck
Continuous crystallizers serve a wide range of applications in the chemical process industries. Optimize system performance by heeding these practical design and operating principles, which apply to the forced circulation (FC), draft-tube-baffle (...

Improving the Reliability of Mechanical Seals

November
2005
Operations And Maintenance
Michael Huebner
With a better understanding of seals, their selection, material considerations, and operation requirements, users can greatly improve equipment reliability and reduce operating costs.

Streamlining the Validation Process

March
2007
Management
Robert Mackey, Tim Flanigan
Today, validation is no longer an afterthought for the design and construction of a new or renovated process or facility. It is, in fact, recognized as an integral part of the total project. Fully integrated services are now available to ensure a...

Correlate Data Effectively

February
2011
Computational Methods
Faruk Civan
Follow these nine simple rules to avoid common pitfalls and get better results.

Choose Materials for High-Temperature Environments

February
2001
Materials
Peter  Elliott
High temperatures, stresses, and the presence of elements such as oxygen, sulfur, or the halogens can add up to trouble. Here is how to screen candidate alloys for such service.

Steam Trap Troubles?

February
2005
Heat Transfer
Trinath Sahoo
First, prevent problems by selecting the appropriate trap and installing it properly. If problems arise, follow these guidelines for diagnosing and correcting them.

Rx for Pharma

March
2009
Critical Issues
Girish Malhotra, P.E.
Chemical engineers could hold the key that helps pharmaceutical companies — facing pressure to control rising drug prices and competition from generics — reduce their manufacturing costs.

Designing Dust Collectors

September
2011
Fluids and Solids Handling
Greg Mehos, P.E.
To assure reliable and safe operation of a dust collector, apply the basic principles of chute and hopper design — which are based on the dust's fundamental flow properties.

Estimate the Capacity of Simple Batch Processes

August
2002
Reactions and Separations
James L. Manganaro
Finding the throughput of a multiple-unit, multiple-step operation, even when it is relatively uncomplicated, is not always an easy matter. Several equations and graphical aids are provided to help determine yearly capacity.

Avoid Sulfolane Regeneration Problems

July
2004
Reactions and Separations
Donald F. Schneider
The regeneration of sulfolane, a common extraction solvent, is difficult. With proper attention to design and operation, problems can be minimized.

Selecting Corrosion-Resistant Materials

December
2006
Materials
Francesco Picciotti, Marcello Picciotti
This article looks at some common corrosion-resistant alloys and gasket materials that are available for use in applications with high pressures and temperatures.

Evaluating Cooling Tower Upgrades

May
2008
Heat Transfer
Tom Dendy
When considering improvements to cooling towers, it's important to perform an economic analysis of the options.

Find Mixing Success through Failures - Part 1

October
2008
Fluids and Solids Handling
David S. Dickey, Gary K. Patterson
Understanding when and why mixing fails in the laboratory is often the only way of avoiding a similar failure in a production-scale reactor.

Bridge the Gap with Semicontinuous Distillation

August
2001
Reactions and Separations
James R. Phimister ,  Warren D. Seider
This processing strategy combines the advantages of batch and continuous operation, providing flexibility and efficiency in a single design.

Evaluating the Economics of Desalination

December
2002
Heat Transfer
Hisham M. Ettouney, Hisham T. El-Dessouky, Peter J. Gowin, Ron S. Faibish
This article presents an in-depth analysis of thermal and membrane desalination economics and outlines a simple procedure for calculating the unit product cost for various desalination processes.

Building Models from Simulator Runs

January
2006
Computational Methods
Aad van Veldhoven, Magali de Macedo
The design-of-experiments approach has the advantage of providing the framework to build complex models with minimum use of time and effort.

Evaluating and Documenting Tower Performance

February
2010
Reactions and Separations
Daniel R. Summers
A good performance evaluation can lead to a significant improvement in column performance and establish a basis for future tower evaluations. <br>

Integrate Compressor Performance Maps into Process Simulation

June
2011
Computational Methods
Grant Stephenson
Transforming the performance maps to a reduced coordinate system that is independent of suction conditions and rotational speeds allows these curves to be accurately incorporated into a process simulator.

Innovations in Food Processing

March
2003
Fluids and Solids Handling
B. G. Swanson, G. V.  Barbosa-Cánovas, M. F. San Martín
Today's savvy consumers want processed foods to look freshly prepared, while still meeting all safety requirements. Conventional thermal treatments are inadequate to fulfill this demand. New nonthermal techniques, such as pulsed-electric fields, are...

Prevent Caking During Solids Handling

May
2005
Fluids and Solids Handling
Brian H. Pittenger, Gabriel I. Tardos , Herman Purutyan
Use these guidelines to avoid potential caking problems. The key steps are to select a material characterization method, identify the factors that can be feasibly controlled and conduct tests to confirm that process/handling changes yield the...

Obtain the Best Physical Property Data

May
2009
Fluids and Solids Handling
Kevin G. Joback
Physical property values are essential for many chemical engineering tasks. This article reviews sources of physical property data, discusses the use of experimental methods to measure properties, and details several types of estimation techniques.

Nitrogen: A Security Blanket for the Chemical Industry

November
2011
Fluids and Solids Handling
Bill Carlson, Joe Dumoit, Paul Yanisko, Shiying Zheng
The benefits of nitrogen blanketing include improved process safety, better product quality, and longer equipment life. Here's how to achieve the desired safety or quality results while minimizing costs.

Integrate EHS for Better Process Design

February
2002
Process Development
Lisa Bendixen
Get a jump on process development by addressing environmental, health and safety (EHS) issues together early in the design and development cycle. The result will be a better process and lower costs.

Can We Believe the Simulation Results?

October
2002
Reactions and Separations
Henry Z. Kister
Be careful of these key issues that may generate differences between a distillation-tower simulation and its actual performance. Simulations do not always square with nuts-and-bolts reality.

Simulating Aqueous Processes

September
2003
Reactions and Separations
Joel B. Christian
Simulation that includes aqueous modeling can also account for full vapor/liquid/solid equilibria modeling, including redox chemistry.

Run Clean with Dry Vacuum Pumps

October
2001
Fluids and Solids Handling
Jim  Ryans, Joe  Bays
The use of dry pumps is growing, replacing workhorse steam jets and liquid-ring pumps. Here is a comprehensive selection guide.

Track Condenser Performance

February
2003
Heat Transfer
Brad Buecker
An effective monitoring program can extend equipment life, improve operations, and yield substantial energy savings.

Pumping System Head Estimation

February
2005
Fluids and Solids Handling
James Anthony
These spreadsheets highlight losses, uncertainties and value of power used, helping you optimize pumping system designs and save on operating costs.

Avoid Problems in Process Water Systems

October
2007
Heat Transfer
Marilyn W. Blaschke, Roger D. Metzler
Prevent corrosion, emulsification and fouling by implementing these operational and chemical measures.

Examining X-Ray Technology

March
2009
Fluids and Solids Handling
Ray Spurgeon
Use X-ray inspection to see whether your product is contaminant-free and packaged properly.

The Flange Factor in Gasket Selection

September
2011
Fluids and Solids Handling
Dave Burgess, John Crandall
Gaskets should be chosen based on service conditions, as well as the type of flanges to be sealed. These principles will help to guide the selection.

Optimize Heat Exchanger Cleaning Schedules

June
2001
Heat Transfer
Brendan R. O'Donnel, Bruce A. Barna, Chris D. Gosling
Get the most out of your heat exchanger by evaluating the trade-offs between a one-time expenditure and reduced operating expenses, increased income, and/or longer operating life span. Brendan R. O'Donnell - Bruce A. Barna - Chris D. Gosling -

Take the Guesswork Out of FRP Corrosion

December
2001
Fluids and Solids Handling
Gunnar Bergman
The lifetime of fiberglass-reinforced plastic equipment and piping often depend upon previous experience. Here's a way to predict and prolong service life.

Optimizing Crystallizer Scaleup

June
2003
Fluids and Solids Handling
Wayne Genck
Explore how mixing parameters impact the crystallization process and recommend ways to improve the likelihood of successful scaleup. The concepts of nucleation and growth, types of mixing, design considerations, agitator parameters and scaleup...

Dynamic Capacity Modeling of Product Development

July
2004
Information Technology
Brian E. Hartman, Jospeh S. Alford Jr., Prashant B. Kokitkar
Avoid large work queues by proactively anticipating the resource needs of your company using dynamic capacity models.

A Simple Approach to Vapor Pressure Prediction

January
2007
Reactions and Separations
Andrew J. DeDoes, Matthew D. Goetz, Michael J. Misovich
This method reproduces the vapor pressure predictions of the Soave-Redlich-Kwong and Peng-Robinson equation of state with a simple Antoine equation that uses constants derived from critical properties and the acentric factor.
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