Chemical Engineering Practice

Understanding Steam Traps

February
2011
Back To Basics
James R. Risko
Steam trap failure can affect process operations and reduce profits. Choosing the right steam traps can improve reliability and reduce cost.

Should You Use Enhanced Tubes?

April
2002
Heat Transfer
Graham T. Polley, Mohamad R. Jafari Nasr
Following this procedure to identify a basic exchanger geometry without performing a full exchanger design and to evaluate where and when heat transfer enhancement can be of benefit.

Fermentation Goes Large-Scale

January
2003
Special Section
Alex Patist, Aristos Aristidou , J. J. Hahn , Pim van Hoek
Designing an economically competitive and environmentally sustainable fermentation route means considering the downstream separations needed to capture the final product during the initial process design.

Formulating Production Planning Models

January
2004
Information Technology
Jeffrey D. Kelly
Optimize petroleum and petrochemical plant production by understanding the mathematical modeling behind nonlinear planning models.

Properly Select Equipment for SIP Systems

August
2007
Fluids and Solids Handling
Tony George
Sterilization-in-place (SIP) systems are essential to the operation of many pharmaceutical and biotech facilities. This article reviews design considerations, selection criteria and performance expectations for control valves, regulators, isolation...

Designing Four-Pass Trays

April
2010
Back To Basics
Daniel R. Summers
Use this procedure to design four-pass distillation column trays and to balance the vapor/liquid ratio on each tray panel.

Bioreactor Design for Chemical Engineers

August
2011
Back To Basics
Gregory T. Benz
Fermentation processes are based on chemical engineering principles. Understand these concepts to achieve optimal bioreactor design.

Properly Clean Out Your Organic Heat-Transfer Fluid System

May
2001
Heat Transfer
Ander  Beain, Jay  Heidari,  Conrad  Gamble
Follow these guidelines for applying side-stream filtration to on-line cleaning, and chemical or mechanical cleaning to equipment that has been drained of fluid.

Follow These Best Practices in Steam System Management

December
2001
Heat Transfer
David  Jaber, Fred L. Hart, Gilbert A. McCoy
These tips on how to improve steam generation, distribution and recovery can help a plant to increase its steam system efficiency by as much as 20-30%.

Optimize Power Consumption in Aerobic Fermenters

May
2003
Reactions and Separations
Gregory T. Benz
By performing the necessary pilot work, and rigorously calculating the full-scale performance instead of using simple rules-of-thumb, significant energy savings can be achieved in fermenters.

Maintaining Piping and Support Systems

June
2005
Operations And Maintenance
Gerry May
With proper pipe support design, installation and maintenance, pipe damage should normally not develop for decades.

Ionic Liquids for Aromatic Extraction: Are They Ready?

December
2006
Reactions and Separations
Sachin T. Anjan
Ionic liquids have already moved into the commercial arena as reaction solvents. This article compares them to conventional solvents and examines their potential for the extraction of benzene, toluene and xylene from reformate.

Step into the Virtual Plant

February
2002
Instrumentation
Gregory K McMillan, Mark S Sowell III, Michael M Mansy
The ability to warehouse process and control system knowledge offers a vast potential for improved operations by sharing a common source of information and avoiding data duplication.

Process Intensification: Has Its Time Finally Come?

October
2003
On The Horizon
Costas Tsouris, Joseph V. Porcelli
Many new technologies are being developed, but several important barriers must be overcome before process intensification is widely adopted.

Selecting a Membrane Filtration System

December
2004
Fluids and Solids Handling
Frank Parma , Wu Chen
Proper design and scaleup of a membrane filtration system requires an understanding of the availability of membrane material, pore size and module configurations. These practical guidelines will help in the selection process.

A Strategy for Excellence in Process Development

October
2008
Process Development
Lionel O'Young, Vaibhav V. Kelkar
Here is how to integrate overall process development activities and identify practices that facilitate commercial process development.

Simplify Experimental Design

January
2010
Computational Methods
Joseph F. Louvar
Save time and money by using this approach to fractional-factorial design of experiments (DOE) for studies involving six or seven variables. <br>

Implementing an IACS Patch-Management Program

May
2011
Information Technology
Kevin Staggs
Maintain state of the art industrial automation and control systems (IACS) by using these steps to support an effective patch management program and implement it with minimum risk.

Working with Non-Ideal Gases

March
2003
Fluids and Solids Handling
Jimmy Peress
Here are two proven methods for predicting gas compressibility factors.

Apply Solubility Theory for Process Improvements

March
2004
Reactions and Separations
Michael J. Gentilcore
For solid compounds that dissolve in solvents but do not ionize, the thermodynamics of solubility can provide valuable predictions and insights.

Improve and Maintain Cooling Tower Efficiency

April
2005
Heat Transfer
James L. Willa
Changing maintenance and/or operating procedures can significantly increase cooling tower performance without major capital expenditures. Here are some tips for ensuring proper design and operation of major tower components.

Increase Powder Flow via Gas Injection

July
2006
Fluids and Solids Handling
Herman Purutyan, John W. Carson, Thomas G. Troxel
Fluidization and air-assisted discharge are two ways to optimize fine-solids handling. However, the choice of technology is as important as designing and operating the system properly.

Use Model-Predictive Control to Improve Distillation Operations

January
2008
Instrumentation
Daniel R. Webb, Robert D. Rounding, Robert J. Conroy, Umesh Mathur
This methodology, based on steady-state and dynamic simulation, can be used to develop the necessary models— and avoid disruptive and costly step testing to the extent feasible.

Choosing Specialty Metals for Corrosion-Sensitive Equipment

July
2010
Back To Basics
Dean Gambale
Specialty metals should be considered for processes that push beyond the corrosion limits of steel. New composites and surface alloy technologies expand the options for defending against corrosion.

Choose the Right Electric Motors for Hazardous Locations

November
2011
Back To Basics
Uriah Van Amerom
Risks associated with operating an electric motor in hazardous areas range from production downtime to injury and death. Learn how to assess the operating environment and select the appropriate motor.

Burning Bright: Trends in Process Integration

July
2001
Process Development
Nick  Hallale 
Process integration has a far wider scope and touches every area of process design. Industries are making more money from their raw materials and capital assets, while becoming cleaner and more sustainable.

Accurately Predict the VLE of Thiol-Hydrocarbon Mixtures

September
2004
Reactions and Separations
Chorng H. Twu, Vince Tassone, Wayne Sim
This methodology can be used to calculate vapor-liquid equilibria (VLE) between thiols and hydrocarbons at any composition, temperature or pressure to improve gasoline fractionation processes.

The G-Value for Agitator Design: Time to Retire It?

March
2007
Fluids and Solids Handling
Gregory T. Benz
This commonly used number does not correctly address the influence of viscosity, and has no relationship to performance parameters such as fluid velocity and blend time. This article recommends actual measures of agitator performance that should be...

Minimize Mechanical Integrity Budget Battles

February
2011
Safety
Daniel A. Long, P.E., Jack McCavit
Chemical processing and manufacturing plants must ensure the mechanical integrity of their equipment. These strategies and tactics can make doing so easier when budget issues arise.

Take the Tedium Out of Writing Process Descriptions

February
2001
Instrumentation
Michael J. Gentilcore
Setting up a special function and a shorthand system on a spreadsheet can improve the descriptions needed for implementing a process control system, while minimizing the monotony in writing them.

Modeling Production-Chain Information

February
2005
Information Technology
Jeffrey D. Kelly
Data alone is not information. Use this model to transform data into vital information for decision making.

Modeling Reactive Absorption

January
2009
Reactions and Separations
Eugeny Kenig, Panos Seferlis
Effective modeling of reactive absorption enhances system design, improves experiment planning for parameter-estimation, and facilitates process operation and control decisions.

Preventing Maldistribution in Multi-Pass Trays

April
2010
Reactions and Separations
Henry Z. Kister, Matthew R. Olsson, Richard Dionne, Walter J. Stupin
This method, based on hydraulic equations in the open literature, calculates vapor/liquid distribution in four-pass trays to correctly predict flooding and efficiency.

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.
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