Presentation on theme: "CRITICAL VARIABLES PROGRAM Get plant operating results with an inexpensive and simple implementation using only PI-ProcessBook and PI-DataLink (NO Programming."— Presentation transcript:
CRITICAL VARIABLES PROGRAM Get plant operating results with an inexpensive and simple implementation using only PI-ProcessBook and PI-DataLink (NO Programming and LOW maintenance!)
AGENDA Introduction Problem: Unit Operating Settings Proposed Solution & Game Plan Details of Critical Variables Program –Displays for current plant status –Reports for deviation tracking Results: Successes & Failures
GENERAL INFO Carolyn Przybylski (sha–BILL–skee) –B.S. Chemical Engineering (1987) –Started with Cytec as Process Engineer -> Production Engineer -> Process Control Engineer –Currently Sr. Manufacturing Systems Engineer –PI System Manager (4 years) Cytec Industries – Fortier Plant –New Orleans, LA –Chemical Manufacturing plant –Continuous Processes (24/7/365) –440+ Cytec employees & 150+ contractors onsite
PI SYSTEM LAYOUT Separate Networks (Process & Office) Two 50K tag servers with PI-to-PI interface Interfaces: –6 DCS (GSE D/3 & Yokogawa) –20+ PLC (Square D, Allen Bradley) –2 APC Systems –Laboratory Mgmt System (LIMS) –Environmental Mgmt System (EMIS) PROCESS NETWORK OFFICE NETWORK Routers/Firewall DCS & PLC Process PI Server (50k) APC Office PI Server (50k) PI-to-PI Server EMIS LIMS Clients
PROBLEM Spent a lot of time & money improving control loops to enable finer control closer to constraints Plant was still being run at “easy” settings rather than economical Some settings could be detrimental to process (plugging) or equipment (corrosion) over the long term Advanced Control option too expensive
“CHEAP & EASY” SOLUTION Needed a system to maintain the plant at target operating points and to track excursions from target CHEAP – used existing PI Clients of ProcessBook and DataLink EASY – no special programming required, just standard ProcessBook, DataLink, and Excel functions Focused effort on developing list of key parameters and their targets/limits and then following up to ensure that unit was run within those limits
WHY USE PI INSTEAD OF DCS? Lab sample results do not reside in DCS, but do reside in PI Some key parameters are calculations that are done in PI, not on DCS Future parameters from other units that were in PI Limited DCS screens used for control; can use PC screen for PI Easy to make changes (more people trained on PI-ProcessBook and Excel than on DCS)
GAME PLAN Step 1: Establish list of critical variables as key indices for the plant and include ranges for TARGET, HI/LO, and HIHI/LOLO Step 2: Develop ProcessBook display to show where plant is currently operating in relation to established targets (snapshot view) Step 3: Develop daily DataLink report to show how much time was spent in each range (% of time) for monitoring off-shift periods
HOW ARE WE DOING RIGHT NOW?
NO VBA PROGRAMMING: MULTISTATE SYMBOLS, ONLY
HOW HAVE WE DONE IN THE PAST?
PI TIME FILTER FUNCTION
TIME INTERVAL FORMATTING =($B$4-$B$3)*24&"h"
CRITICAL LIMITS ENTRY FOR REPORT Cell “$L10” used in Time Filter Formula
TIME FILTER FUNCTION EXPRESSION (LO/HI)
TIME FILTER FUNCTION EXPRESSION (LOLO/HIHI)
% Time in Target Ranges: –Unit 1 = 95% –Unit 2 = 80% Steam Savings of M$1.6 Long term savings: TBD –Extend equipment life? –Reduce outages due to plugging? Communication key to success (supervisors, operators, engineers) RESULTS
Originally one display and one report applied to operating parameters for one unit Now three units using displays and reports for operating parameters As successes are realized, more units should begin similar implementations Have added displays and reports for Cooling Tower Operation and Quality Control ADDITIONAL STEPS
COOLING TOWER DISPLAY
USED DATASETS TO DISPLAY LIMITS ON TRENDS
QUALITY CONTROL DISPLAY
SUMMARY OF CRITICAL VARIABLES PROGRAM Simple method to maintain key variables on target using basic functionality of PI & Excel Can be applied to multiple areas such as production, cooling towers, & quality control KEY COMPONENT: COMMUNICATION! –Tool just helps to provide FOCUS on key issues & problem areas –Once target deviations are identified, operators, engineers, and supervisors MUST work together to apply solutions (specific communications/training)
QUESTIONS / COMMENTS? Thank you for your time and interest! Phone: (504)