Archives :: Technical & Practical

Displaying 141 - 160 of 527 stories.
June 1, 2012
One of the most energy-intensive utilities for many facilities in the chemical process industries (CPI) is the steam system. Traditionally, steam-use optimization has centered on efficient heat transfer and eliminating waste [ 1]. Further optimization can involve a broader look at how steam supply and consumption interact dynamically throughout a large complex. This type of optimization often results in...
http://www.chemengonline.com/technical_and_practical/Dynamic-Modeling-for-Steam-System-Control_9388.html
June 1, 2012
A variety of performance problems can arise in distillation towers during startup. Many are caused by equipment, hardware or process conditions. Hardware issues may be related to instrumentation, tower internals or ancillaries. Instrumentation malfunctions are also common during startup and are predominantly related to liquid level indicators, online analysis of key components and in some cases...
http://www.chemengonline.com/technical_and_practical/Distillation-Avoid-Problems-During-Tower-Startup_9389.html
June 1, 2012
  A gas flare is an elevated vertical conveyance found accompanying oil wells, gas wells, drilling rigs, petroleum refineries, chemical plants, natural gas plants and so on. Although modern flare systems are specifically designed to reduce the thermal radiation, pollution and acoustic impact of a flare, a considerable amount of radiation is nevertheless emitted by an operational flare as a result of...
http://www.chemengonline.com/technical_and_practical/CFD-Analysis-of-Heat-Transfer-From-Flares_9390.html
June 1, 2012
Throughout the chemical process industries (CPI), the need to drain a tank or process vessel arises. In batch-type plants, it is a regular occurrence and is one factor that affects the total cycle time per batch and ultimately the entire production capacity of the plant itself.  Figure 1. In a vertical cylindrical, flat-bottom tank, liquid is flowing into the outlet nozzle (point 1) located at x...
http://www.chemengonline.com/technical_and_practical/Draining-Vessels_9398.html
May 1, 2012
Failures of piping due to vibration-induced fatigue are a serious problem in the chemical process industries (CPI) and a matter of concern for the safety and reliability of plant operations. Due to the complexity of flow-induced vibrations in pipes, no closed-form design solutions — those that can be expressed in terms of well-known functions — are available. In this article, we present a...
http://www.chemengonline.com/technical_and_practical/A-method-for-quantifying-pipe-vibrations_9271.html
May 1, 2012
Reducing freshwater consumption and wastewater discharge at large petroleum-refining and chemical-production facilities can lower costs, while allowing plants to expand production capacities without having to secure additional freshwater resources and without having to enlarge their wastewater treatment plants. The key approaches to saving significant amounts of water are: improved water management...
http://www.chemengonline.com/technical_and_practical/Water-saving-strategies-for-the-CPI_9277.html
May 1, 2012
Quite often, during the design of conveying systems, not enough attention is paid to the design of the conveying pipeline and its components. This disregard often leads to some major conveying system problems such as low conveying rates, conveying line plugging, excessive wear and tear in the conveying line, high conveying system pressure drop, product breakage, fines and streamer generation and product...
http://www.chemengonline.com/technical_and_practical/Rules-of-Thumb-For-Pneumatic-Conveying-Pipelines_9280.html
May 1, 2012
The growth in use of centrifugal compressors in chemical process industries (CPI) applications in recent decades has been brought about by four factors: 1) advances in dry gas seal technology; 2) modern aerodynamic, rotor-dynamic and thermodynamic knowledge and techniques; 3) advanced manufacturing methods to producing accurate rotating parts and various complex components with reasonable costs; and 4) the...
http://www.chemengonline.com/technical_and_practical/Centrifugal-Compressors-for-CPI-Plants_9296.html
April 1, 2012
The approaches currently used by process integration specialists to assess the opportunities for the integration of reboilers are frequently erroneous and lead to proposals that have to be rejected at the detailed engineering stages or worse, to commissioned reboilers that do not perform properly. This article examines the integration of both vertical and horizontal thermosiphon reboilers, and covers the...
http://www.chemengonline.com/technical_and_practical/Thermal-Integration-Of-Reboilers_9180.html
April 1, 2012
At one time, the design of distillation columns and other major components for the chemical process industries (CPI) required engineers to make one-at-a-time calculations in order to project what-if scenarios covering the processes, equipment, raw materials and capital necessary for renovation or construction. If an engineer was fortunate, he or she might have had access to central computer facilities that...
http://www.chemengonline.com/technical_and_practical/Better-Chemistry-By-Design_9181.html
April 1, 2012
Instrumentation best practices that are taught in colleges and published in standards are intended to be broadly applicable, guiding users in every industry and geography. However, for outdoor applications in cold climates, where the temperature can fall below –40°C, the optimum installation may be very different from those recommended via best practices, to ensure reasonable performance...
http://www.chemengonline.com/technical_and_practical/New-Measurement-Practices-for-Cold-Climates_9182.html
April 1, 2012
In the chemical process industries (CPI) it is often necessary to verify material specification at various points in the process. In that effort, it is usually impossible — or at the very least impractical — to measure the whole production. Instead, small samples must be extracted from a parent population. Such is the case in particle size characterization of bulk solids, process streams and...
http://www.chemengonline.com/technical_and_practical/Sampling-Particulate-Materials-the-Right-Way_9183.html
April 1, 2012
When a process plant is set up, an owner has several things in mind; the market demand for his product and hence the plant capacity, the plant cost, the space availability, space for future expansion and so on. Once a plant has been built, there is equipment that has additional design margins. For example, columns and pumps are specified with 10% margins. Control valves are specified with approximately a...
http://www.chemengonline.com/technical_and_practical/Revamping-Your-Process-Plant_9184.html
March 1, 2012
Thermodynamics cannot yield any information about the intermediate states of a given reacting system. These intermediate states are the subject matter of chemical kinetics, which studies reaction rates and mechanisms. Chemical kinetics will predict what chemicals are present while thermodynamics will predict the limits of distribution of those chemicals in the different phases [1]. The design and analysis...
http://www.chemengonline.com/technical_and_practical/Thermodynamic-Analysis-Of-Electrolyte-Systems_9057.html
March 1, 2012
Distillation is one of the most extensively used operations in the chemical process industries (CPI). It is a highly energy-intensive unit operation, and continuously rising energy costs make it imperative to look for ways to reduce energy requirements. Some energy-saving configurations can increase capital investment costs, so the benefits need to be weighed carefully. Various techniques, such as heat...
http://www.chemengonline.com/technical_and_practical/Distillation-Optimization-By-Vapor-Recompression_9064.html
March 1, 2012
Rotating machines, such as pumps, compressors, gas turbines, steam turbines and electric motors, play crucial roles in most chemical process industries (CPI) facilities. Increasingly, advanced condition monitoring is being used to improve the operation and maintenance of these workhorse components. The use of well-designed condition-monitoring systems, predictive-maintenance strategies and failure...
http://www.chemengonline.com/technical_and_practical/Condition-Monitoring-for-Rotating-Machinery_9073.html
February 1, 2012
Level measurement and control in process vessels can be one of the most challenging applications in which to obtain consistently safe and reliable results. Part of this difficulty may be due to the fact that the sizing of the vessel and selection and installation of the level instruments are frequently performed by different people at different times, rather than evaluated holistically as a system. Level...
http://www.chemengonline.com/technical_and_practical/Vessel-Sizing-and-Level-Instrumentation_8947.html
Pages: « Previous  1 2 3 4 5 6 7 [8] 9 10 11 12 13 14 15 16 17 Next »

Get more from ChemEngOnline.com
Get email updates in your inbox

 

Subscribe to:
Chemical Engineering Magazine

Chemical Engineering Magazine and Archives

Plant Cost Index

Join us on... Twitter LinkedIn

LinkedIn Groups

Our LinkedIn group is now over 28,000 members strong!

  1. Join other CPI professionals from all over the globe and share best practices, expertise, concerns and more.
  2. Provide feedback to Chemical Engineering Editors


Current members represent Worley Parsons, DuPont, SABIC, Fluor, Air Products, LyondellBasell, Nalco, Dow Chemical, Dow Corning, BASF, Jacobs Engineering, ExxonMobil, Shell, Chevron and more.

Join Now



We also offer the following subgroup for more targeted discussions:

Tools
Search the Buyers' Guide

Plant Cost Index

Facts at Your Fingertips (archive)

Ask the Experts

Back Issues
X
To access this area, please log in or create an account.
Username:
Password:
Forgot your password?
Request it now.
Processing...
Live chat by BoldChat