TECHNICAL SESSION II 1 JUNE 2017 - Tissue World Miami · new equipment for turbomachinery and reactors at MAN Diesel & ... -Case study for a Tissue plant -Water separation system

TECHNICAL SESSION II 1 JUNE 2017

Wagner Canelhas is currently a sales engineer in the division of new equipment for turbomachinery and reactors at MAN Diesel & Turbo Brasil since 2016. He worked in advertising and marketing at Escola Estadual Adolpho Bloch between 2007 and 2009. Wagner worked as an art director in advertising at AB Comunicações in 2009. He graduated in Mechanical Engineering from Universidade Federal Fluminense in 2016, where he partici-pated in the Formula SAE project for three years, in which he was responsible for the fairing of the vehicle and in parallel for the team’s marketing management. He joined MAN as an intern in September 2014.

VACUUM BloWEr TECHNology For TiSSUE plANTS - a case study for the most modern vacuum plANT oN TiSSUE MACHiNES iN BrAzil WAgNEr CANELHAS SAlES ENgiNEEr TUrBoMACHiNEry & rEACTorS MAN, BrAzil

INNOVATIONS & IMPrOVEMENTS: SUSTAINABLE, PErFOrMANCE ENHANCINg AND ENErgY SAVINg SOLUTIONS

1 < > MAN Diesel & Turbo Author Current topic 00.00.2012 [optional: Brand]

MAN Diesel & Turbo

Wagner Canelhas

Sales Engineer

Rafael Martos

Head of Sales

Vacuum blower technology for Tissue plants A case study for the most modern vacuum plant on Tissue machines in Brazil

2 < > Tecnologia de Sopradores de vácuo para Tissue Wagner Canelhas Tissue World – São Paulo 2017 05.2017

Introduction Part 1

Introduction - Paper Machines

- Tissue Machines

- Hood

- Felt Wires

- Vacuum levels and flow rates for each product

- Typical vacuum flowchart

Vacuum Systems for Tissue

- Liquid ring pump

- Main Components

- Operating characteristics

- Use of "False Air"

- Vacuum blowers

- Main Components

- Operating characteristics

- Comparison between systems

- Advantages and disadvantagess

- Case study for a Tissue plant

- Water separation system


Technological characteristics - Energy Efficiency

- Constant Speed

- Variable blades

- Multiple levels of vacuum

- Speed variation

- Thermal Recovery Possibilitie

- Hood inflation air

- Shower water heating

- Building heating / false ceiling

- Combustion air preheating

- Felt Conditioning

- De Costa curves (constant drainage)

- Break-in and drag-load phenomena

- Measurement and control of dewatering

Modernizations of existing plants - Typical vacuum flowchart

- Modernizations list of references

Conclusion

Introduction Part 2


Vacuum levels for other applications

Type of

produced

paper

Anual

production

(tons/year)

Vacuum gauge pressure

(meters of water column)

Total vacuum flow

(m³/min)

Maximum vacuum

flow

(m³/min)

Tissue 55.000 -2,5 até -5,0 920 580 @ Suction Roll

Tissue 30.000 -4,5 550 550 @ Single Point

Pulp 250.000 -0,5 até -6,5 900 215 @ Suction roll

Paper 150.000 -0,2 até -7,0 1200 414 @ Press Roll

Paper 20’000 -0,5 até -7,0 1980 221 @ Uhle Box

Usually Tissue is one of the processes that most demand vacuum in single points


Vacuum systems for Tissue Liquid ring pumps

Components:

A – Rotor with blades

B – Liquid ring seal

C – Pump housing

D – Suction section

E – Discharche section

F – Interface blades / liquid ring

Additional Details:

Air and water inlets and outlets

Bearing support

Single or dual stage operation

One motor for multiple pumps

Pulleys configuration


System features:

Volumetric machine

Pulsations and vibrations

High pressure variantions

High vacuum levels (>80 kPa)

Small to medium lifetime

Requires water sealing

Low flow variation

− Works under “Bleed Air”

Low maximum flow per housing

− High number of pumps per

installation (>4)

Lower compression efficiency

Small change in consumption under

partial loads

Vacuum systems for Tissue Characteristics of pumps at constant speed

Suction point

𝐕 = Cte

Vacuum

Power

Air Flow

Bleed air


Vacuum systems for Tissue Vacuum blower

Components:

Rotor and impeller(s)

Stator

Housing

Hydrodynamic bearings (oil)

Up to 4 suction points

Additional Details:

Single or multiple stages

One motor per machine

One blower for multiple vacuum

machines

Dedicated lubrication system

Diffuser blades

Gearbox

Hydrodynamic bearings

Housing

Stator

Rotor


System features:

Dynamics machine

Low pressure variation

− Delivers until 4 pressure levels

− Throttle valves

Pressure levels up to 80 kPa

Long lifetime, exceeding 15 years

Compresses air only

− High compression efficiency

High flow variation

− 110 to 80% for RC technology

− 110 to 30% for RT technology

Few machines per installation

− For Tissue, from 1 to 4 machines

Economy in partial loads

Possibility of complementary

thermal recovery

Suction point

𝑷 = Cte

Vacuum systems for Tissue Characteristics of blowers at constant speed

Vacuum

Power

Air Flow


Comparison between technologies Advantages and disadvantages

Application / Feature Vacuum blower Liquid ring pump

Operating flow rate per equipment Higher flow rates Lower flow rates

Operating pressure range Up to 80kPa Up to around ~98 kPa

Pressure variation Low: Throttle valve High

Flow rate variation High Low: Bleed air

Number of machines per Tissue plant 1 to 3 4 or more

Compression efficiency High Low

Possibility of thermal recovery High - Exhaust air Low - Warm Water

Water consumption Very low High

Vibrations and pulses Low High

Dimensions and weight Low High

Noise level Similar

Availability Higher Lower

Maintenance requirements Low Frequent


Comparison between technologies Air / Water separation system

Vacuum pumps:

Separators with barometric legs

Pre-separator packages

One separator per vacuum point

Open or closed water cycle for

sealing system

− Cooling towers

Vacuum blowers:

At least one separation box per

vacuum level (pressure)

− Concrete or steel boxes

− Positioning on the same level as

the paper machine or lower

− Pumps for water extraction


Case Study - Tissue Plant Comparison of new Tissue plant in Brazil

Rated item Vacuum blower Liquid ring pump

Rated power (electric motor) 57% (43% reduction) 100%

Maximum power consumption 50% (30% reduction) 80%

Average power consumption 40% (40% reduction) 80%

Number of machines 1 x RT 71-1 5 vacuum pumps

Preliminary thermal recovery 14 % (86% reduction) 80%

OPEX / LCC 55 % (45% reduction) 100%

Water consumption in open circuit < 1% (99% reduction) 100%

For this project the blowers consume, under average power, half the power of the pumps

First reference of the single-stage machine in Brazil

Forecast to have already started operation in 2019

Largest Yankee Cylinder ever made for Tissue machines in the world

Taken as the most modern Brazilian vacuum plant in Tissue

Effects of Break-in economy were not considered in this study


Vacuum Blowers Energy efficiency - constant speed


Vacuum Blowers Adjustable diffusor blades

Functionality:

Modify the flow resistance and alter

the machine operating curve

Provide modulation of flow and

pressure of the machine

Maximize operation during felt

conditioning and llifetime

Additional data:

Diffusor blades can operate

between 10 to 26º

Operated by pneumatic valve and

servo motor integrated into the casing

Allows reduction of project flow by up

to 30%

Automatic system


Vacuum Blowers Energy efficiency – diffusor blades


Vacuum Blowers Energy efficiency – diffusor blades


Vacuum Blowers Energy efficiency – Speed variation


Felt conditioning Constant drainage –De Crosta curves

De Crosta curves (1980)

The drainage rate of the felt should

be constant during the lifetime of the

felt.

Study on new, used and half-life

felts

Conclusion of the ideal vacuum

curve for paper machines

Lifetime (30 days)

Transition to old felt (5~7 days)

Known phenomena:

Break-in

− Time spent on felt compaction

Drag Load

− Higher load on machine rolls

− Risk of premature felt rupture


Felt conditioning Comparison of vacuum technologies


Ideal solutions

Measurement of the level drainage of felts and automation of the vacuum

system

Drive in the vacuum system making use of choke valves and diffusing blades

reducing the effects of Break-in

Variation of flow to lower values than design, reducing drag-load effect

Usual solutions

Chemical or mechanical compaction of felts at the beginning of their useful

lifetime

Low production operation to compensate for operation outside the design point of

the vacuum system

Felt conditioning Possible solutions


Thermal recovery Theoretical Principle - Preliminary Calculus

Enthalpy of moist air

Considerations for thermal exchange at constant pressure (specific heat cp)

Consider absolute humidity to calculate the enthalpy of water separately

Consider enthalpy of dispersed water steam in air

ℎ = 𝑐𝑎𝑖𝑟 ∗ 𝑇 + 𝑥 ∗ (𝑐𝑤𝑎𝑡𝑒𝑟 ∗ 𝑇 + ℎ𝑠𝑡𝑒𝑎𝑚)

Case Study for Tissue Machine

Temperature that the air leaves the blower - 150 ºC

Ideal thermal recovery temperature for air - 60 ° C

Consideration of specific heat of water as 1.84 kJ / kgºC

Consideration of specific heat of air as 1.006 kJ / kgºC

Consideration of steam enthalpy as 2501 kJ / kg

Absolute humidity of 0.15 kg H2O / kg air

Mass flow rate of 25 t / h = 25,000 / 3600 kg / s

Result obtained: 798 kW of energy to be recovered

Added to energy efficiency, savings of 80% compared to the consumption of vacuum pumps


Thermal recovery Hood air - Simplified


Thermal recovery Hood air vent – preheating


Thermal recovery Hood air - burner


Thermal recovery Hood air – Steam heated


Thermal recovery Pre-Heating of the shower water


Thermal recovery Building heating / False ceiling

Building heating

Relevant in regions of southern Brazil, where winter is severe and heat energy can be

saved by using blower air to heat the building.

It can be applied in a complementary way to the previously proposed recoveries.

No use of heat exchangers

False ceiling heating

In order to avoid precipitation of droplets in the ceiling where the paper machine is

installed, it is common to construct a heated false ceiling.

Application will largely vary according to present temperatures, size and production of

the paper machine in question.

It can also be applied as thermal recovery complementary to previous ones

No use of heat exchangers


Thermal recovery Preheating of combustion air


Modernization of existing plants Proposed adaptations

What is, or can be kept

Vacuum pump system (temporary

backup)

Air / water pre-separators

Vacuum pipeline between pumps

and paper machine

What shall be implemented:

New vacuum system (blowers)

New motors for blower drive

Separation boxes made of concrete or

steel

Control valves at the point of greatest

flow and pressure.

Opcional

Frequency inverter

Transformers


Modernization of existing plants Common operation - List of world references

Plant Customer Product Country Year

Archangelsk BM2 JSC Arkhangelsk Sack Kraft Paper Russia 2016

Shiwha Shindaeyang BM1 Shindaeyang Paper Linerboard Korea 2015

Shintanjin PM 1 Hansol Paper Co. Ltd Art Paper Korea 2015

Oberkirch PM 5 Koehler Paper Group Paper Germany 2015

Duffel TAD Tissue Sofidel Benelux NV. TAD Tissue Belgium 2015

Osan BM 1 Dong Won Paper C. Ltd Testliner Korea 2015

Daejeon BM 31 Hansol Paper Co. Ltd White Board Korea 2015

Daejeon BM 32 Hansol Paper Co. Ltd White Board Korea 2015

Ovaro BM 1 & 2 Reno di Medici Board Italy 2015

Ansan Korea BM 1 Korea Paper Linear Board Korea 2014

Dörpen PM 3 UPM Nordland Fine Paper Germany 2014

Lexington NW 1 Kimberly-Clark Non Woven USA 2014

Banpong PM 3 Thai Paper Printing/Writing Thailand 2014

Hyunpoong BM 1 Kyungsan Paper Corrugated Medium Korea 2014

Nortrup BM 1 Delkeskamp Fluting/Liner Germany 2014

Mislata PM 7 Miquel y Costas & Miquel Silk/Tipping paper Spain 2014

Olsany PM 5 OP Papirna Finepaper Czech Republic 2013

Beech Island TM 3 Kimberly-Clark Tissue USA 2013

Allo TM 1 Georgia-Pacific Company Tissue Spain 2011


Conclusion

Vacuum blower technology

It has several advantages for the papermaking process, especially in the sanitary

paper sector (Tissue)

Tendency to expand and spread in Brazil (as already happened in China)

Modernization studies being done in several plants and obtaining good results with

returns of the investment between 1 to 3 years.

Vacuum pump technology

Ideal for high vacuum levels and applications where fluid sealing is crucial.

More competitively efficient in small plants when fewer pumps are applied (<400 cfm)

Especially used in large scale in pulp mills (less concern with water consumption and

thermal recovery, besides own electrical generation)

Thermal recovery technologies

Great application potential, however reduced when compared to countries with severe

winters

May be associated with generation solutions with gas and steam turbines

31 < > MAN Diesel & Turbo Author Current topic 00.00.2012 [optional: Brand]

MAN Diesel & Turbo

Wagner Canelhas

Sales Engineer

Rafael Martos

Head of Sales

Vacuum blower technology for Tissue plants A case study for the most modern vacuum plant on Tissue machines in Brazil

Documents

TECHNICAL SESSION II 1 JUNE 2017 - Tissue World Miami · new equipment for turbomachinery and reactors at MAN Diesel & ... -Case study for a Tissue plant -Water separation system