ADVANCED CONTROL

FOR INDUSTRIAL WASTEWATER TREATMENT

1

Esko Juuso

Control Engineering, Faculty of Technology

University of Oulu, Finland

Esko.juuso@oulu.fi

16.3.2015

WASTEWATER TREATMENT

•Process alternatives

•Measurements

• Intelligent analyzers: combine measurements

•Control

•Diagnostics: Detection of operating conditions

16.3.2015

2

Shortage of nutrients

Too much nutrients

High oxygen

Low oxygen

High temperature

Low temperature

High flow

Low flow

Very good

Low reduction

Settling problems

Very good

Warnings

TREND ANALYSIS

• Trend index: scaled values, two windows

• Change

k

nki

j

L

k

nki

j

S

T

j

LS

kXn

kXn

kI )(1

1)(

1

1)(

Alarm

Alarm

There was a problem, but things are now getting better?Very good or

Very good

or

Variable specific

TREATMENT RESULTS

Low

reduction

Settling

problems

Very good

Very good

SUBMODELS

Water treatment

Fuzzy LE blocks

BioMass

Load

- Load

- Nutrients

- Oxygen

- Temperature

Condition of

the biomass

INTELLIGENT ANALYSERS CONTROL

Intelligent analyser

(Software sensor)

Control

Decision making

Intelligent analyser

(Software sensor)Intelligent analyser

(Software sensor)

Control

Decision makingControl

Decision making

On-line modelling- identification

High-level control & diagnosticsweighting of stragies, switching,

cascade control,

plant-wide control, expertise

Performance

analysis

Adaptationadaptation mechanisms,

gain scheduling, scaling

Measurement

technology

CONCLUSIONS

• Step-by-step procedure• Nonlinear scaling

• Trend indices (time windows, importance)

• Change of trend indices

• Deviation index

• Prognostics

• Early detection• Warnings

• Alarms

• Diagnostics, DSS & Control

• Hybrid models are needed• Uncertainty (features of influent, microbial

composition)• Mechanistic + Databased + Intelligent

Variable specific

Intelligent indices

Combinations Process states