CRITICAL VARIABLES PROGRAM

Get plant operating results with aninexpensive and simple

implementation using onlyPI-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 LIMITSENTRY 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 TODISPLAY LIMITS ON TRENDS

QUALITY CONTROL DISPLAY

SUMMARY OFCRITICAL 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!

Email: Carolyn.Przybylski@cytec.com

Phone: (504) 431-6468