Money spent to reduce deadtime (e.g. greater agitation, faster valves, faster measurements) will be wasted if the controller is not tuned faster. You may have wonderful process dynamics but loop performance will be lousy if the PID is not tuned to be commensurate with the opportunity. A loop with excessively slow tuning and low deadtime …
Category Archive: Metrics
Jun
02
Top Ten Limitations – Deadtime
Deadtime sets the ultimate limit to loop performance. Deadtime is any delay in the action needed to exceed the threshold for the start of error correction. The loop deadtime is the sum of pure actuation, correction, or recognition delays and the equivalent deadtime from lags smaller than the largest time constant in the loop. For …
May
19
Monitoring Process Performance Online
Process efficiency measurements involve the measurement of process flows and utility or raw material flows. The energy efficiency depends upon the utility temperatures and heat transfer coefficient. The raw material efficiency depends upon feed concentrations and the desirable reaction rate to product and the undesirable reaction rate to a byproduct. For simply changing a stream’s …
Apr
28
Identifying Equipment Performance Problems
Plants often consist of many production units and trains of equipment. The production units may produce raw materials as intermediates in a series of processes that lead to predominant product. Often intermediates or byproducts are also sold. Trains of equipment feed into a common tank that may feed other trains of equipment. Recycle streams further …
Mar
17
Master of Space and Time
The lack of space and time kills process control innovations. The lack of space for new cables, I/O card, and new sensors and the time required for the implementation does more than just slow down implementation, space and time prevents the genesis of new ideas. As I was giving a talk to the American Institute …
Dec
23
XY Plots for Operations and Process Analysis
Process visualization and interaction for operations are about to enter the 21st century after being stuck in the 1980s. Emerson and major companies in the process industries and universities through organizations such as the Center for Operator Performance are doing research on how to increase the effectiveness of operators to match the increased capability of …
Dec
06
Roundtable Presentation – Life Science Industry Forum
The Food and Drug Administration issued the guideline “Guidance for Industry, PAT — A Framework for Innovative Pharmaceutical Development, Manufacturing, and Quality Assurance” in September, 2004. The objective of this guidance was to “describe a regulatory framework (Process Analytical Technology, PAT) that will encourage the voluntary development and implementation of innovative pharmaceutical development, manufacturing, and …
Nov
04
Batch Process Analytics – update -
Over the last three years the DeltaV future architecture team has worked closely with Lubrizol to develop and install a beta version of Emerson’s on-line batch analytics. At Emerson Exchange 2010 the Lubrizol Corp. represented by Robert Wojewodka, Technology Manager, Process Improvement Team Leader, accepted the 2010 PlantWeb Excellence Award for exceptional application of PlantWeb …
Oct
28
Use of Data Analytics in Pharmaceutical Manufacturing
Earlier this year I had the pleasure of speaking at a conference on FDA and PAT for Pharma Manufacturing, FDA-Partnering with Industry. This 2-day conference was co-sponsored by the FDA and the University Of Rhode Island College Of Pharmacy. The primary object of this conference was to “Disseminate current and accurate information on Process Analytical …
Oct
15
ISA Automation Week 2010 – The Most Important Week in my Career
ISA automation week was a success in terms of technical content. The renewed emphasis on technical presentations particularly in automation and control rejuvenated my interest in the International Society of Automation. I moderated a panel discussion on loop tuning. Harold Wade setup the ISA simulator for the following cases that were designed by me to …
