Productivity & Yield Improvement in Discontinuous Processes

Productivity & Yield Improvement in Discontinuous Processes Chris Morse - Honeywell

2 © 2015 Honeywell International All Rights Reserved

Raw Material Costs in the Chemicals Industry

• Raw Materials after feedstock significant cost element for Chemicals Manufacturers

• Optimization of raw material usage reduces cost of goods sold

• Automation of Raw Material additions using Experion increases efficiency & productivity

• Techniques shown applicable to Batch & other discontinuous processes

Typical Financial Basis for Chemicals Manufacturing


Raw Material Automation - Challenges

• Physical/Chemical material characteristics vary

• Automation equipment requires tuning for different materials

• Manual actions are prone to error

• Processes/Formulations change over time

• Certain materials e.g. catalysts or modifiers are high cost items

• Raw Material Addition accuracy has significant QA impact


Experion Functions Available to Help

• Experion Batch Manager - Scalable for many sequential processes

• Sequential Control Modules - Raw material additions

• Advanced Sequence Visualization - Operator sees status & problems

• Control Modules - Advanced totalizer & controller facilities - Auxiliary Calculation

• Procedure Analyst - Raw Material Usage Report

REG PV

REG CTL

LOG

DIG COMP

HPM Tools

ExperionTools


Experion Batch Manager – Cycle Time Reduction

Batch 52 Start

Mix Sample Discharge Material 2 Material 1 Mixer Start

Reactor Start

Server Based Mixer Cycle Time

Batch 53 Start

Mix Sample Discharge

Material 2

Material 1 Mixer Start Reactor Start

Controller Based Mixer Cycle Time Cycle Time Reduction

6-12 secs

2 secs

12 Sec

2 Sec

Serv

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tep

trans

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Con

trolle

r ste

p tra

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• Material flows differ affecting cut-off point

• Wide variation in quantities – same equipment

• Flow measurement characteristics vary by material

Flowmeter Feed Addition

Material A

Material B

Material C

FT

Continuous Process

Autoclave

Tank T

Setup/Start Totalizer

Open Valve T

Open Valve A/B/C

Start Pump

Close Valve A/B/C

Stop Pump

Close Valve T

Material Qty Units

Material A 187.0 Kg

Material B 19.8 Kg

Material C 24.5 Kg

Flowrate

Mat B Mat C Mat A

Target Value

Flowrate

Mat B Mat C Mat A

Pre Target 4

Pre Target 3

Pre Target 2

Pre Target x Reached Challenges:

• Up to 4 pre-targets per totalize

• Switch between multiple totalizers in an SCM

• Reduce cycle time of totalizer min 50 mSec

Optimization Levers:

Pre Optimized Flows

Optimized Flows


Flow Control Material Addition

Material A

Material B

Material C

FI

Continuous Process

Autoclave

Tank T

FC

Flowrate Material A

Pre Target 2

Pre Target 1

Mode = Auto SP = Full Flow

Mode = Auto SP = Trickle Flow

Mode = Man OP = 0%

Slope determined by OPROC

Setup/Start Totalizer

Open Valve T

Mode = Auto SP= Full

Start Pump

Mode = Auto SP = Trickle

Mode = Man OP = 0%

Stop Pump

Pre Target 2 Reached

Pre Target 1 Reached

OPCV = 0%

Close Valve T

Mode = Man OP=100%

Line Drain Time Complete

Material Qty Units

Material A 187.0 Kg

Material B 19.8 Kg

Material C 24.5 Kg

• Minimise dosing time with accurate cutoff

• Post target cutoff content of line can affect cost/quantity

• Maintenance of flow & cutoff values

Addition challenges:

• Experiment with controller modes & flow set points for minimum addition target deviation

• Drain line & offset against line content – may be equipment specific value

• Maintain values as Material or Equipment value – not recipe parameters



Gain in Weight Addition

W1

Tank S1

32% Dry

Matter

Mixer 2 m3

Intermediate Storage 5 m3

Final Storage 10 m3 Paper Machine

Coating Station

Open Vale T1

Calculate Target

Open Valve S1

Start Pump

Close Valve W1

Wait for Stabilization

Stop Pump

Target Reached

In Tolerance?

Close Valve S1

No Yes

Tare 1

Tare 2

Weight Tolerance

Un-Discharged

Stabilization Time

• Reaching a Stable weight value

• In flight error – varies with time & material

• Residual material on sides of hopper

• Material lot to lot variation

Challenges:

• Tune out instability

• Compensate for in flight error & material differences in a calculated target

• Alert Operator to un-discharged material



Material Quantity Target Tuning

B101

B102

B103

B104

B105

+ve Tolerance Recipe Target 24.2Kg -ve Tolerance

Improvement: Maintain Accuracy for each Batch

Material A Addition over 5 Batches

B101

B102

B103

B104

B105

+ve Tolerance Recipe Target 24.2Kg -ve Tolerance

Normal Variation with Giveaway Applying Material A Bias to next batch over 5 Batches

B101 B012 B105 B104 B105 Mean Bias

over 10 Batches

- 0.2 -0.4 +0.3 -0.2 -0.3 -0.05

B101 B012 B105 B104 B105 Mean Bias

over 10 Batches

+0.2 +0.3 +0.4 +0.5 +0.6 +0.25

In spec but with material giveaway &

possible quality impact

Bias correction calculated for each batch applied to recipe target.

In spec & consistently

closer to target for better yield

and quality

Mean bias over several batches alert raised if absolute value gets too high

–before spec deviation

Bias calculation tries to correct low delivery but the root cause is an

equipment problem. Deviation will eventually occur

Bias monitoring for Equipment Problem Detection


Next Batch Compensation & Real Time Release

B101

B102

B103

B105

B105

Material B

Material A

Mix

Monitoring

Sample Set Batch Status

In Tolerance?

No Yes

End: Release/Quarantine/Reject End: Release

Positive difference vs target

Negative difference vs target

Calculated compensation vs normal target

“Normal” Target Value

-ve Tolerance

+ve Tolerance

Mixer Operation

• Accurate measurements are available

• Batches feed to a downstream process

• Quality values can be calculated or inferred

Assumptions

Real Time Release – no quality deviations detected. Batch moves to next stage – downstream/packaging


Reduced Sampling = Further Cycle Time Reduction

Batch 53 Start

Mix Discharge

Material 2


Cycle Time Reduction

Batch 53 Start

Mix Sample Discharge

Material 2


Monitoring

Sampling Once Per Batch

Reduced Sampling – Deviations Only

• Checks for raw material qty deviations

• Checks other quality variables which can be automated – e.g. mix time

• Alerts operator to quality problems

• Sets status of batch: Released/Quarantine/Rejected

• MAY have Supervisor Access

Monitoring Phase


Procedure Analyst - Materials Usage Reporting

• Material Usage Report ‒ Show target, actual and deviation material amount on a per batch basis

between specified start and end dates ‒ Search for target value deviations ‒ Any material addition SCM can be recorded for reporting


Raw Materials Optimization – Calculating the Value

• Assumptions: ‒ Production is 340 days/year 24 hours/day ‒ Production Rate 480 Tons/day ‒ Revenue $1500/ton ‒ Raw Material Costs 35% of revenue

• Annual Revenue $244M • Annual Raw Material Costs $85M • 1% Reduction in Raw Material savings $850K


Questions to Ask

• Can our raw material additions be automated? • Can material addition measurements be

improved? • How could variations in raw material additions be

smoothed out? • What data is available for raw material usage? • Can quality checks be automated? • Is there a better way of adding some

materials?


What is the value of 1% Raw Material Savings?

Technology

Productivity & Yield Improvement in Discontinuous Processes