Energy is Always a Major Cost Factor

International Symposium on Energy Efficiency in

Pulp and Paper Industry, September 20, 2011

Jussi Manninen and Janne Poranen

VTT Technical Research Centre of Finland

2 27/10/2011

Contents

Why energy is a major cost factor and why energy prices are high

What are the targets for efficiency improvement

What can be done to increase energy efficiency

Operations

Monitoring

Technology (examples from Metso)

Research and development of future technologies for energy

efficient paper processes

Conclusions

3 27/10/2011

Why is energy a major cost factor

Pulp and paper making is energy-intensive

Cost of energy is on the rise

Oil and gas prices are rising

Diversification of energy supply due to energy security and

environmental concerns leads to increased use of renewables

=> leads to increased competition on wood

Other costs are introduced, like taxes and emission trading

4 27/10/2011

Energy demand is projected to grow substantially

Source: World Energy Outlook 2010, IEA

US and China annual

consumption is ca

2200 Mtoe

5 27/10/2011

Renewables need to be supported to accelerate their introduction

to market

Source: World Energy Outlook 2010, IEA

6 27/10/2011

New oil sources need to be found

Source: World Energy Outlook 2010, IEA

7 27/10/2011

How to control cost and increase energy efficiency

Understand energy use

Monitor energy use and benchmark

Develop an energy strategy

Implement an energy management system

Implement energy efficiency measures

Optimise energy purchase

8 27/10/2011

How to start implementing energy management

Collect data on energy use and document data to get an energy balance

Production and energy reports

DCS and additional measurements

Process simulation

Establish baseline performance

Set target values to aim to

Benchmarking

BAT-values

Theoretical values

Analyse energy use patterns and trends to identify key factors that influence energy consumption

Evaluate the process performance and equipment to identify improvement potential and opportunities

Experience

Analysis

Process simulation

9 27/10/2011

Electricity use benchmarks

Sähkönkulutus

0

500

1000

1500

2000

2500

3000

Kra

ft, B

leac

hed, H

WSGW

TMP

ONP, d

eink

ed

Line

rboa

rd

Recy

cled

Boa

rd

New

sprin

t

Coat

ed G

round

wood

Coat

ed F

ree

Tissu

e

kW

h/t

Tyypillinen

BAT

Teoreettinen

Typical

BAT

Theor.

ElectricitySähkönkulutus

0

500

1000

1500

2000

2500

3000

Kra

ft, B

leac

hed, H

WSGW

TMP

ONP, d

eink

ed

Line

rboa

rd

Recy

cled

Boa

rd

New

sprin

t

Coat

ed G

round

wood

Coat

ed F

ree

Tissu

e

kW

h/t

Tyypillinen

BAT

Teoreettinen

Typical

BAT

Theor.

Electricity

Source: Francis, Towers and Browne, 2002, Energy Cost Reduction in the Pulp and

Paper Industry – An Energy Benchmarking Perspective, Paprican

10 27/10/2011

Steam use benchmarks

Höyry

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

Kra

ft, B

leac

hed, H

WSGW

TMP

ONP, d

eink

ed

Line

rboa

rd

Recy

cled

Boa

rd

New

sprin

t

Coat

ed G

round

wood

Coat

ed F

ree

Tissu

e

GJ/t

Tyypillinen

BAT

Teoreettinen

Typical

BAT

Theor.

SteamHöyry

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

Kra

ft, B

leac

hed, H

WSGW

TMP

ONP, d

eink

ed

Line

rboa

rd

Recy

cled

Boa

rd

New

sprin

t

Coat

ed G

round

wood

Coat

ed F

ree

Tissu

e

GJ/t

Tyypillinen

BAT

Teoreettinen

Typical

BAT

Theor.

Steam

Source: Francis, Towers and Browne, 2002, Energy Cost Reduction in the Pulp and

Paper Industry – An Energy Benchmarking Perspective, Paprican

11 27/10/2011

Factors affecting consumption

INTERNAL FACTORS

•Loads

Load characteristics

•fast dynamic

•constant power etc.

Load (type, class etc.)

•individual device

•device group

•plant unit

Load groups

(load composition)

•drying

•wet end etc.

•Paper mill size and age

•Process arrangements

•Production type

•Product type

•etc.

LO

AD

MO

DE

LS

EXTERNAL FACTORS

• climate

• weather

• season

• day of the week

• time of the day etc.

Source: Alanen, R., 2000, Analysis of electrical energy consumption and neural network estimation

and forecasring of loads in a paper mill, VTT Publications 424.

12 27/10/2011

Improve performance using these three cornerstones of energy

efficient processes

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Energy cost have influence on the cost-optimum production rate

Source: Sivill, L. and Ahtila. P, 2009, Paper Machine Production Efficiency as a Key

Performance Indicator of Energy Efficiency, Proceedings of PRES-09

14 27/10/2011

Example of specific steam consumption as function of production

Source: Sivill, L. and Ahtila. P, 2009, Paper Machine Production Efficiency as a Key

Performance Indicator of Energy Efficiency, Proceedings of PRES-09

15 27/10/2011

Monitoring electricity consumption – a case study in the pulp and

paper industry

Goals

Estimate the impact of operational practices on energy consumption

Obtain information on the success of process design

Evaluate potential and economics of equipment re-sizing

Detect maintenance demands of process equipment in advance before any significant deterioration in performance occur

How it was done

Data acquisition system was installed and connected through standard interfaces to the process automation system, the energy control system, measurements of the electrical network and different equipment registers

30 kW or larger drives were selected for the monitoring, and sampling interval was 1 minute

A monitoring period of several months was used to capture all possible load situations

Power consumption measurement was estimated using either correlation methods or type-specific load curves of electric motors.

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Monitoring included 20 % of drives but over 80 % of installed

capacity

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Many drives are run at partial load

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Benefits from electricity load monitoring

Improved knowledge of electricity use helps to improve control and

forecasting

Surveillance of electricity use promotes best practices e.g.

between shifts

Provides long-term data for energy savings analyses for

drives

pumps, blowers

Points out maintenance needs for equipment

Gives feed-back to designers to improve dimensioning

Energy efficient solutions

© Metso

EnergyOperator monitoring and reporting tool

Date Author Title 20

Standard

reports

Energy

balances

Operator

EE-Info

• Total balance

• Heat balance

• Water balance

• Time reports

• Grade reports

• Line level

• Sub-processes

• Parameters

• Web manual

• Check lists

Monitoring

displays

EnergyOperator – modules

Analyses

© Metso

Energy savings at stock preparation Case: Eucaplyptus refining with OptiFiner Pro

Date Author Title 21

Solution

• Low consistency refining

technology

• One OptiFiner Pro replaces two

traditional refiners

Result

Stock manufacturing and handling

40% electrical energy savings

compared to traditional

refiners

© Metso

• Long dwell time in the vacuum

zone

• Increases felt dewatering at a lower

vacuum level than a slotted cover

• Decreases friction between the

cover and the felt

• Cost savings and benefits

- Increased dewatering

- Lower friction - lower press drive load

- Longer felt lifetime - longer felt change

interval

22

Cost-saving felt conditioning solution

Perforated uhle box cover based on SolidCoat technology

Wet end dewatering

© Metso

Dryer section energy savings through optimized doctoring

Low friction doctor blades

Date Author Title 23

Assumptions

Width 7 m

Machine speed 900 m/min

Load 300 N/m

Dryer cylinder radius 0.915 m

µ Glass fiber 0.5

µ Carbon fiber 0.2

Number of blades 50

Running days/year 300

Friction and drive powers

Relative power consumption of doctor

blade materials

Based on laboratory tests in simulated paper machine

environment

4

3

2

1

0

Carbon

fiber

Glass

fiber

Steel Bronze

Solution

• Doctor blade material with low

friction coefficient

© Metso

Energy savings and low maintenance costs PowerDry Plus air dryer

Results

• Lower web temperature

• Less water penetration

• Energy savings

• Lower maintenance costs

Date Author Title 24

Maintenance costs

Energy costs

PowerDry Plus Gas IR Electrical IR

600

500

400

300

200

100

0

Paper finishing

k €/a

700

Machine width 8 m

PowerDry Plus with 3 nozzles and IR dryers with

similar evaporation

Annual operating time 8,000 h/a

Energy source natural gas - natural gas 30 €/MWh

- electric power 55 €/MWh

25 27/10/2011

Some future directions for improving energy efficiency in paper

and boardmaking

Improved water removal from the web

Savings in steam 4 % per 1 %-unit of dry content

Material development to reduce friction

Savings in electricity consumption of drives

Process simplification

Thinner paper products

Considerable savings in raw material and energy per functionality of paper (i.e. per printing surface)

High consistency forming

Savings in short circulation pumping

Replacement of fiber by fillers

Savings in pulping and drying

Dry forming

Savings dependent on how much moisture is needed to form the web and how much energy is needed for fluidisation of fibers in air

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Drivers for new resource efficient technologies

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Technical specifications:

Forming unit Press

Gap/Hybrid/Fourdrinier

Web speed 2500 m/min Max line load 2000 kN/m

Headbox flowrate 240 l/s/m Web width ~210 mm

Web width 300 mm Belt width 700 mm

Fabric width 500 mm

New process and product concepts

• Fundamentals of web forming

• Paper structure

• Dewatering

• Wet end process development

• Mixing, deaeration, screening

• Wet-pressing

• Sensor development

• Papermachine clothing development

• Chemical and raw material studies

SUORA – Research environment

Running concepts

• Once-through (no circulation)

• Small volume circulation

• 15 m3 ~300 kg

• Large volume circulation

• 100 m3 ~3 000 kg

Research case: forming fabrics and energy consumption

• Target of study was to find out if forming fabrics can affect energy

consumption on forming section.

• On SUORA-former friction of forming fabric on vacuum box and

wattage of drive motor can be measured

• SUORA environment has

support a new forming

fabric type development

with lowered energy

consumption

– First product application has

been sold and the

installation in paper mill will

be done in 10/2009

Forming fabric designs can effect energy consumption

Difference in this case more than 10 %

29 27/10/2011

Conclusions

Energy prices are expected to stay high in the future and energy

prices can be reflected on the price of wood, too

You need to increase understanding on where and when energy is

used to improve operations and know where to invest

There is still room to improve energy efficiency with best available

technology

For more radical changes, we need to develop new technologies

that are based on better understanding of the phenomena taking

place in papermaking

30 27/10/2011

VTT creates business from

technology