Chemical Engineering Practice

Find Mixing Success Through Failures - Part 2

December
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. Here we examine mixing in stirred-tank reactors and provide guidance on scale-up.

Understand the Real World of Mixing

March
2010
Back To Basics
Thomas Post
Most chemical engineering curricula do not adequately address mixing as it is commonly practiced in the chemical process industries. This article attempts to fill in the gaps by explaining flow patterns, mixing techniques, and the turbulent,...

Don’t Let Baffle Tray Flood Baffle You

July
2011
Reactions and Separations
Henry Z. Kister, Matthew Olsson
Use this new correlation based on window liquid velocity to predict baffle tray capacity.

Applying Bus Technologies in Process Control

December
2002
Instrumentation
Ed Smigo
Fieldbus technologies have become increasingly popular in process control applications. This article highlights the practical applications and economics of various buses, so that an engineer can choose the best one for his or her process.

Understand Temperature Change in Process Stream Mixing

September
2006
Heat Transfer
Anil K. Mehrotra, Dharmendra Tiwary
The isobaric and adiabatic mixing of process streams can yield an outlet stream temperature that is either in between, higher than, or lower than the inlet stream temperatures. This article uses simulation to explore temperature-change scenarios in...

Use Spreadsheets to Estimate Modeling Parameters

February
2008
Computational Methods
Tomas B. Co
Dynamic process modeling based on non-uniformly sampled data and multiple sampling runs, even for nonlinear systems, can be performed using spreadsheet implementations of the weighted-least-squares (WLSQ) and Runge-Kutta WLSQ methods.

Understand the Fundamentals of Centrifugal Pumps

October
2010
Back To Basics
J. Howard Kelly, P.E.
Efficient and reliable pumps can significantly improve a plant’s bottom line. This article reviews important concepts that a chemical engineer must understand and the factors that need to be considered when selecting radial-flow centrifugal pumps.

Understand Thermodynamics to Improve Process Simulations

December
2011
Computational Methods
David Hill, Fred C. Justice, P.E.
Selecting a thermodynamic model is an important step in process simulation — one that many engineers overlook. This overview of applied thermodynamics can help you choose the right model for your process.

Squeeze More Out of Complex Columns

July
2002
Reactions and Separations
Piyush Shah
These distillation setups can cut capital and operating costs by up to 30%, and increase separation efficiency. Here is a straightforward method for evaluation.

Understand Flow Patterns in Glass-Lined Reactors

November
2004
Reactions and Separations
Christopher J. Ramsey, David S. Dickey, Keith E. Johnson , Kevin J. Bittorf
Physical modeling and computer simulation provide insights into the performance of a glass-lined reactor.

Safely Handle Powdered Solids

December
2005
Fluids and Solids Handling
Daniel E. Silva, Robert Zalosh, Russell Kahn, Stanley S. Grossel
Understand some of the accident scenarios that result in dust explosions, and follow these suggestions for preventing them.

Improving Heat Exchanger Designs

April
2007
Heat Transfer
Christopher A. Bennett, David C. King, R. Stanley Kistler, Thomas G. Lestina
This article defines and explains the factors that affect heat exchanger design margins. With the proper application of design margins, capital costs can be lowered and plant operations improved.

Validate Your Engineering Software!

July
2001
Instrumentation
Michael  Tanzio
You really can't guarantee that applications work correctly unless you take specific steps to validate the software.

Don't Get Burned Picking Dry-Type Flame Arresters

October
2002
Fluids and Solids Handling
Stanley G. Grossel
These commonly used devices rely on an internal medium to extinguish flame fronts and take the punch out of shock waves, protecting piping, equipment and personnel. Selecting such equipment involves considering the probable type of combustion,...

Guidelines for Selecting Sterilizing-Grade Filters

March
2005
Fluids and Solids Handling
Monica Cardona, Philip Blosse
Determine if your bioprocess needs a sterilizing grade filter, and if so, use these guidelines to select the proper one for your application.

Succeed at Catalyst Scale-Up

June
2006
Reactions and Separations
Ben Wagner, Donald R. Engelbert, J. Todd Osbourne, Jeff Braden, Richard Allen, Uday T. Turaga, William H. Beever
Follow these principles to reduce the time required for scale-up and commercialization to improve the resource effectiveness of the effort.

Determine the Right Eye Protection

September
2011
Safety
Harry J. Elston
Wearing the appropriate protective eyewear begins with a thorough safety assessment. These guidelines clarify how to identify hazards and select protective equipment to avoid eye injuries.

Basics of Centrifugal Pump Selection

May
2002
Fluids and Solids Handling
Bernadette Pyzdrowski, Drew B. Schiller, Kimberly Fernandez, Michael B. Smith
Tips for specification and operation that provide for cost-effectiveness and reliability.

Screw Feeders: A Guide to Selection and Use

February
2003
Fluids and Solids Handling
Hermann J. Feise, Steven W. Couch, Thomas L. Krieger, Timothy Bell
Gain insight as to what screw feeder is best for your application. Plus, learn how to size, specify and test screw feeders.

Troubleshooting Tangential Flow Filtration

June
2003
Reactions and Separations
Kent Iverson
Tangential flow filtration (TFF) is commonly used to concentrate and dialyze solutes. It generally involves the circulation of the feed solution over a filter surface. This article presents a brief overview of the principles governing TFF, and...

Efficient Technology Evaluation

February
2007
Critical Issues
Francesco Citro, Reuel Shinnar
To stay competitive in today's economic climate, rapid and effective assessments of new technologies is a must. Requiring a minimal amount of data, this powerful method can effectively evaluate new ideas and research programs at an early stage...

Choose the Right Elastomer

June
2008
Materials
William M. Stahl
Match a material's performance to process conditions to reduce leaks, improve safety and extend the mean time between failures (MTBF).

Improve Flange Joint Reliability

January
2011
Back To Basics
John Ludman, Mike Emery, Thomas Sandbrook
Proper design, installation, and maintenance of flanged connection systems can prevent loss of containment and process interruptions. Follow this seven-step approach to ensure reliability of this critical process equipment.

Inhibiting and Monitoring Corrosion

March
2012
Heat Transfer
Gary Geiger, Mel J. Esmacher, P.E.
Understand corrosion and ways to control it, and implement these monitoring techniques to improve cooling water system efficiency and reliability and reduce energy consumption.

Take Another Look at Steam Traps

June
2001
Fluids and Solids Handling
S. Raghavi  Chari
Think twice before installing a steam trap. In the case of superheated lines, steam traps may prove to be a waste of time, effort, and money

Evaluating Dryers for New Services

December
2003
Heat Transfer
Charles G. Moyers
Continuous dryers are accurately and easily evaluated using laboratory-scale simulators combined with the specific drying rate approach.

Effectively Manage the Lifecycle of a Product

July
2007
Information Technology
Baha Korkmaz, Marty Martin
By incorporating the batch standards S88 and S95 into the entire product lifecycle, companies can optimize their processes and project management. This enables them to rapidly get their products to market — a critical factor in staying competitive.

Minimize Scale-Up Risk

March
2010
SBE Special Section
Bertil Stromberg, J. Brad Cort, Thomas Pschorn
Proven commercial-scale equipment already exists for many operations involved in producing biofuels from lignocellulosic feedstocks.

Reduce Piloting Time and Cost

July
2011
Process Development
David A. Berg, Michael T. Cleary
Pilot-scale experimentation is essential to establish a sound foundation for a new chemical processing unit. These best practices can reduce the time and cost involved in process development.

Optimize Pipeline Design for Non-Newtonian Fluids

March
2002
Fluids and Solids Handling
Alejandro Anaya Durand, Cinthya Alejandra Anguilar Guerrero,  Edgar Amaro  Ronces
Use this graphical method to determine pipe diameter, fluid temperature and pressure drop for laminar and turbulent flow.

Implementing an EHS Management Information System

May
2004
Information Technology
Jill Barson Gilbert
Information technology issues are just as important as business and environmental, health and safety considerations. Follow these ten tips to deply an effective EMIS with a positive return on investment.

Eliminate Iteration from Flow Problems

March
2008
Fluids and Solids Handling
John D. Barry
This article introduces a novel approach to solving flow and pipe-sizing problems based on two new dimensionless quantities that are independent of line size and flow.

Predicting Emissivities of Combustion Gases

June
2009
Heat Transfer
Alireza Bahadori, Hari B. Vuthaluru
Use this new correlation, which employs easy-to-solve algebraic equations to estimate gas emissivities, to simplify the design and optimization of boilers, furnaces and other combustion equipment.

Learn to Effectively Operate and Maintain Pumps

December
2011
Back To Basics
Daniel Kernan
Centrifugal pumps play a central role in chemical processing. Proper pump operation and maintenance can improve a facility's productivity, reduce downtime, and trim costs.

Uncovering the Realities of Simulation

May
2001
Computational Methods
Andrew  Vieler, Marco S. Satyr, Oscar  Santollani , Rajeev  Agarwal, Yau-Kun Li
Running sophisticated process simulations does not guarantee correct results. You need to understand the thermodynamic assumptions underlying the program and how to ensure proper applications.

Size Letdown Lines for Pressure Surges

November
2001
Fluids and Solids Handling
Gianni  Anci
A high-pressure gas flow in a letdown circuit can cause damage to piping and equipment. Here is how to design a system to avoid damage should a pressurized gas flow occur GianniAnci-

Profiting From Your Pumping System

September
2003
Fluids and Solids Handling
Aimee McKane  , Vestal Tutterow,  Don Casada
Identify ways to minimize the lifecycle costs of your pumping system

Improve Solids Handling During Thermal Drying

November
2004
Fluids and Solids Handling
Herman Purutyan, John W. Carson, Thomas G. Troxel
Follow these guidelines for ensuring the proper flow of slurries, pastes and wet powders to achieve a dried product with the desired characteristics.

Selecting and Using Bolted Head Closures

April
2007
Fluids and Solids Handling
John C. Birkmire, P.E.
Proper design, fabrication, assembly and operation of a pressure vessel closure are essential to ensuring product containment, integrity and quality.

Solving Phase Equilibrium Problems

September
2008
Reactions and Separations
James R. Reinhardt, Terrence L. Chambers
Use this optimization-based approach to analyze multi-component, multi-phase Equilibria.

Visualizing the McCabe-Thiele Diagram

December
2009
Reactions and Separations
Paul M. Mathias
Use this spreadsheet-based visualization and interactive analysis of the McCabe-Theile diagram to understand the foundations of distillation engineering. <br><br>

Identifying Corrosion and Its Causes

April
2011
Fluids and Solids Handling
Gary Geiger, Mel J. Esmacher, P.E.
An important first step in maintaining equipment reliability and efficiency is understanding the various types of corrosion damage that can occur.

Optimize Mixing by Selecting the Proper Baffles

February
2002
Fluids and Solids Handling
Julian B. Fasano, Kevin J. Myers, Mark F. Reeder
It is common knowledge that baffles promote better flow in an agitated vessel, but how to apply them and what kind to use take some ingenuity.

Production Modeling for Multimodal Operations

February
2004
Information Technology
Jeffrey D. Kelly
Two new views for production modeling are introduced - production flow networks and production flow maps - that focus on unit operations and feedstocks, respectively.

Beware of Pitfalls of Carbon Dioxide Freezing Prediction

March
2005
Heat Transfer
Steve Chafin , Tim Eggeman
Carbon dioxide freezing in a cryogenic system can result in plugging and other operational problems. This article offers insights into the carbon dioxide freezing phenomenon.

Pipeline Pressure Drop: A New Design Correlation

June
2006
Fluids and Solids Handling
Roger Gilmont
A linear equation has been derived to accurately calculate the flowrate of fluids in the laminar and turbulent regions, and to derive an equation for use in the transitional regions.

Selecting Entrainers for Azeotropic Distillation

March
2009
Reactions and Separations
Lionel O’Young, Madhura Chiplunkar, Vivek Julka
This systematic methodology uses residue curve maps to identify and evaluate substances that can facilitate distillation by breaking an azeotrope.

Realize Greater Benefits from CFD

March
2001
Fluids and Solids Handling
Ahmad H. Haidari, Andre  Bakker,  Lanre M. Oshinowo
Computational fluid dynamics has moved from mainframes to PCs and laptops. Newer and better software lets you conduct analyses not possible before, and regular engineers, not just experts, can now carry out CFD.

Air Heater Cleaning Simplified

October
2001
Heat Transfer
Brad Buecker
This high-pressure water washing technique can be used to clean Ljungstrom-type air heaters.

Reduce Costs with Dividing-Wall Columns

May
2002
Reactions and Separations
Dennis O'Brien, Douglas A. Stewart, James W. Harris, Michael A. Schultz, Mohamed S.M. Shakur, Steven P. Rosenblum
These distillation columns can significantly reduce capital and energy expenses vs. conventional multicolumn arrangements.

Computationally Evaluate Self-Reactivity Hazards

February
2003
Reactions and Separations
Edward S. Shanley, Michelle R. Murphy, Surendra K. Singh
Here is a method that rates the tendency of new compounds to self-explode without the need to perform extensive laboratory tests.

Real World Modeling of Distillation

July
2003
Reactions and Separations
Harry Kooijman, Rajamani Krishna , Ross Taylor
Previously, simulations based on nonequilibrium, or rate-based, models were considered impractical due to their complexity. However, with ever-increasing computing power, these simulations are not only feasible, but in some circumstances they should...

Clarifying Centrifuge Operation and Selection

August
2004
Fluids and Solids Handling
Victor Norton ,  William Wilkie
Before selecting a centrifuge for your application, understand its principles of operation and investigate the key process variables.

Integrate Process Simulation and Process Synthesis

October
2005
Computational Methods
Dominic Chwan Yee Foo, Michael Lynn McGuire, Murugan Selvan, Zainuddin Abdul Manan
The design of a new process using computer simulations to analyze a process flowsheet based on the onion model can save time, effort and, ultimately, money.

Uncovering the Realities of Simulation, Part 2

June
2001
Computational Methods
Andrew  Vieler, Marco S. Satyro, Rajeev  Agarwal, Yau-Kun Li,  Oscar  Santollani
Simulation software is a commonly used design tool, thanks mainly to its availability on the desktop. However, one has to understand thermodynamic basics before accepting the desktop's final answer.

Streamlining Crystallization Process Design

January
2004
Fluids and Solids Handling
Christianto  Wibowo, Ka M. Ng, Lionel O'Young
Use phase diagrams to develop reliable crystallization processes quickly and cost effectively.

Designing a Facility for API Development

March
2006
Plant Design
Terrence Fay, Yasha Zelmanovich
Kilo labs are instrumental in scaling up the production of active pharmaceutical ingredients. This article discusses the critical factors that must be considered to design such a facility.

Selecting Laboratory Reactors

August
2007
Reactions and Separations
Francesco Picciotti, Marcello Picciotti
This article outlines some of the considerations involved in selecting and specifying a reactor system for research and development applications.

Developing Screening Cost Estimates

July
2011
Process Development
Richard P. Palluzi, P.E.
Making decisions based on estimates derived from weak data is counterproductive. Use this established methodology to prepare scoping and screening cost estimates for pilot plants quickly and accurately.

Effectively Control Column Pressure

January
2001
Reactions and Separations
Andrew W. Sloley 
Maintaining proper pressure can play a crucial role in the stable operation of a distillation column. Here’s how to select the most appropriate pressure-control scheme.

Shortcut Distillation Calculations via Spreadsheets

December
2002
Reactions and Separations
Jake Jevric, Muhammad E. Fayed
This method uses a numerical solution to the McCabe-Thiele diagram to find the theoretical number of stages for binary and pseudo-binary systems,then calculates the actual number of stages, reflux ratio and column dimensions.
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