Chemical Engineering Practice

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
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.

Designing a Facility for API Development

March
2006
Plant Design
Terrence Fay
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
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.

Design Reactors via CFD

December
2001
Reactions and Separations
Ahmad H. Haidari
Using computational fluid dynamics to design commercial-size batch and continuous reactors can eliminate subjective experience and empiricism, leading to better-designed, more-efficient units.

Avoid Internet Pitfalls

April
2003
Information Technology
Tim Headley
When developing your website, take these preventative measures to steer clear of any potential lawsuits.

Ensure Proper Design and Operation of Multi-Pass Trays

June
2005
Reactions and Separations
Mark Pilling
To function properly at optimum capacity and efficiency, multi-pass trays must be designed so that the liquid and vapor flows are properly balanced. This article provides guidance on how to achieve that.

Reduce Risk When Sourcing Abroad

October
2010
Fluids and Solids Handling
Gregory T. Benz
Purchasing lower-cost process equipment from vendors in developing nations can be an attractive proposition in times of economic austerity. When sourcing outside local channels, keep the points discussed here in mind to avoid costly problems that go...

Get More Out of Single-Stage Distillation

February
2002
Reactions and Separations
Ryan C. Schad 
Try these practical ways to boost capacity, increase product quality or reduce cycle time in batch and continuous systems.

Ease Control Valve Selection

November
2002
Fluids and Solids Handling
Trevor Bishop
With so many types and options available, choosing the right control valve can seem daunting. Selection can be simplified by considering the process fluid, the service requirements, how the various valves function, and seeing how each valve will...

Reduce Dust Explosions the Inherently Safer Way

October
2003
Fluids and Solids Handling
Faisal I. Khan
This article is aimed at the development of a framework for dust explosion prevention and mitigation that explicitly incorporates the principles of inherent safety. As distinguished from engineered and procedural safety features, inherent safety...

Dividing-Wall Columns Find Greater Appeal

May
2007
News Feature
Gerald Parkinson
Conceived more than seven decades ago, dividing-wall columns are now only gaining widespread acceptance. The reasons— the drive to save energy and advances in computer technology that have overcome the burden of doing complex column internal designs.

Form Nanoparticles via Controlled Crystallization

October
2008
Reactions and Separations
Thomai Panagiotou
This continuous bottom-up approach allows precise control of the crystallization process to achieve size, distribution and quality goals, as well as realize the benefits of process intensification.

Save Energy Through Automation

January
2010
Instrumentation
Douglas C. White
Identifying the right automation investments — those with low costs and high impacts — can result in millions of dollars in energy savings for petrochemical plants. <br>

Easily Assess Complex Safety Loops

March
2001
Instrumentation
Lawrence  Beckman
Many safety instrumented systems rely on dissimilar redundant field devices, and this can complicate required analyses. These equations will enable field personnel to handle such situations readily.

Optimize Control Room Communications

October
2001
Instrumentation
Brad A. Walker
Faced with more distractions than ever, operators need an environment that is conducive for dealing with abnormal, as well as normal, situations. Effective control room design can help.

Control and Optimize Nonlinear Systems

February
2003
Instrumentation
Pradeep B. Deshpande
Turbocharging a contrained model predictive controller (CMPC) with fuzzy logic allows CMPCs to be applied over nonlinear systems

Is Your Cold Lime Softener Effective?

December
2007
Reactions and Separations
Loraine Huchler
If your plant's utility system is experiencing problems, the culprit may be the clarifier. Understanding how to diagnose and correct off-spec clarifier operation will allow downstream units to function more efficiently and reliably.

Use Oxygen to Improve Combustion and Oxidation

July
2010
Reactions and Separations
Reed J. Hendershot
Substituting oxygen for air is often a low-cost, easy-to-implement option that can reduce capital costs, lower emissions, and improve process flexibility and reliability.

Reduce Your Compressed Air Costs

October
2011
Fluids and Solids Handling
Ron Marshall
Annual operating expenses for compressed air systems can exceed the equipment’s purchase price. Follow these seven steps to implement efficiency measures that yield cost reductions.

Select the Right Spray Nozzle

June
2001
Reactions and Separations
Peter  Welander
Finding the proper nozzle for specific applications doesn't have to be difficult. By applying basic concepts of nozzle technology, you can create a droplet profile that best suits your needs.

Hydrogen: Liability or Asset?

September
2002
Reactions and Separations
Nick  Hallale
In a petroleum refinery, viewing hydrogen as an asset rather than a liability can lead to increased profits. The key is in the mindset. A typical investor uses money to make money. This article shows you how to use hydrogen to make money.

Handling Flammable Liquids

July
2003
Fluids and Solids Handling
James C. Mulligan
Identify electrostatic hazards associated with liquid processing and understand the precautions available to control them.

Rotating Equipment

October
2005
Fluids and Solids Handling
Kazim Akhtar
Protect compressors and turbines by using piping strainers and following the line procedures outlined in this article.

Scaling Fixed-Bed Catalyzed Processes

March
2007
Reactions and Separations
Jonathan H. Worstell
The new parameter introduced here will yield more meaningful results when a fixed-bed reactor is scaled up for process development or scaled down for plant support.

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
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
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.

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
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.

Selecting a Membrane Filtration System

December
2004
Fluids and Solids Handling
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.

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
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.

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
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.
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.
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