Improvement of the Richardson-Zaki liquid-solid fluidisation model on the basis of hydraulics (PPT)

(1)

Delft University of Technology

Kramer, Onno

Publication date 2018

Document Version Final published version

Citation (APA)

Kramer, O. (2018). Improvement of the Richardson-Zaki liquid-solid fluidisation model on the basis of hydraulics (PPT). 16th Multiphase Flows conference and shore course, Dresden, Germany.

Important note

To cite this publication, please use the final published version (if applicable). Please check the document version above.

Copyright

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons. Takedown policy

Please contact us and provide details if you believe this document breaches copyrights. We will remove access to the work immediately and investigate your claim.

This work is downloaded from Delft University of Technology.

(2)

15 November 2018

(3)

Improvement of the Richardson-Zaki

liquid-solid fluidisation model

on the basis of hydraulics

Onno Kramer

15 November 2018

(4)

o

Introduction

o

Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

(5)

● Introduction

o

Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

(6)

1 _{Waternet Drinking Water Department}

2 _{HU University of Applied Sciences Utrecht,}

Institute for Life Science and Chemistry,

3 _{TUD Delft University of Technology,}

Faculty of Civil Engineering and Geosciences

4 _{TUD Delft University of Technology,}

Faculty of Mechanical, Maritime and Materials Engineering

5 _Omnisys

Consultancy

Onno Kramer1, 2, 3, 4

Eric Baars1

Peter de Moel3, 5

Wim van Vugt2

Johan Padding4

Jan Peter van der Hoek1, 3

Hydraulic modelling of liquid-solid fluidisation in drinking water treatment processes

(7)

Objective Materials & methods Results & discussion

Introduction

Introduction Conclusions Questions

1.2 million clients

(8)

Introduction

 Background: (water cycle)

 Field: (drinking water treatment processes)  System: (multiphase flows)

 Process: (softening)

 Fluidisation: (liquid-solid = water-calcite pellets)

(9)

Introduction

 Field: (drinking water treatment processes)

 System: (multiphase flows)  Process: (softening)

Source Coagulation Sedimentation Infiltration Filtration Ozone Softening BACF SSF Reservoir Network

No chlorine!

(10)

Introduction

 Field: (drinking water treatment processes)

 System: (multiphase flows)

(11)

Introduction

 Fluidisation: (liquid-solid = water-calcite pellets) OH- + HCO3- ↔ CO32- + H2O

CO₃2- _{+ Ca}2+ _{→ CaCO}

3↓

10 - Hardness reduction to 1.4 mmol/L

- Reduces solubility of lead (public health) and copper (environment) - Economic benefits and comfort

- Reduction of washing powder

- Increase life time hot water equipment - Cleaner laundry, tasteful tea

(12)

Introduction

Hard water NaOH Soft water Pellets Seeding 11

(13)

o Introduction

● Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

(14)

Objective

 Objectives:

• Increasing sustainability

• Reducing chemical use

• Improving water quality

 Method: improved model based on hydraulics (porosity)  Focus: crystallisation on specific surface area

(15)

Objective

 Objectives:

• Increasing sustainability • Reducing chemical use • Improving water quality

 Method: improved model based on hydraulics (porosity)  Focus: crystallisation on specific surface area

(16)

o Introduction

o Objectives

● Materials and methods

o

Results and discussion

o

Conclusions

(17)

Objective Materials & methodsMaterials & methods Results & discussion

 Starting point: most popular fluidisation model  Reference: Richardson-Zaki (1954)

 Model analysis: influence of parameters  Introduction: hydraulic model components  Experiments: pilot plant research

 Particles: CaCO₃ pellets, garnet sand, crushed calcite  Data matrix: (grain size, temperature, water flow)  Validation: data comparison

(18)

 Model analysis: influence of parameters

 Introduction: hydraulic model components  Experiments: pilot plant research

(19)

 Introduction: hydraulic model components  Experiments: pilot plant research

Porosity

Index Superficial _velocity

Terminal velocity

(20)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³] Terminal velocity Formula

Classical Richardson-Zaki equation

= < 0.2, = 4.65 0.2 ≤ < 1, = 4.4 −0.03 1 ≤ < 500, = 4.4 −0.1 ≥ 500, = 2.4 General expression = ₁ 2

Garside & Al-Dibouni equation −

− =

Khan & Richardson −

− =

Index

(21)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³] Terminal velocity Formula

− =

Index

(22)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³] Terminal velocity Superficial velocity Index 21

(23)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³] Terminal velocity Index Minimum fluidisation velocity Incipient porosity

Granular activated carbon filtration backwash:

ε ≈ 0.45

Pellet softening fluidisation: ε ≈ 0.55

(24)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³] n=2.4 inertial regime n=2.6 n=2.8 n=3.0 n=3.2 n=3.4 n=3.6 n=3.8 n=4.0 n=4.2 n=4.4 n=4.6 n=4.8 viscous regime Minimum fluidisation Terminal velocity Incipient porosity Minimum fluidisation velocity Formula

− =

Index

(25)

R a ti o : s u p e rf ic ia l / te rmi n a l s e ttl in g v e lo c ity [-] Porosity [m³/m³]

Minimum fluidisation

velocity

Terminal velocity

Brown-Lawler (improved Schiller-Naumann)

= 24 1 + 0.15 . + 0.407 1 +8710 Carman-Kozeny =180+ 2.87_. 24 Index = log , 1 − log , = 1 1 − = Interpolation

(26)

 Introduction: hydraulic model components

 Experiments: pilot plant research

Porosity

Index Superficial _velocity

Terminal velocity

Carman-Kozeny (at minimum fluidisation)

Brown-Lawler (at terminal settling settling)

= 24 1 + 0.15 . + 0.407 1 +8710 =180+ 2.87_.

(27)

 Model analysis: influence of parameters  Introduction: hydraulic model components

 Experiments: pilot plant research

(28)

(29)

 Particles: CaCO₃ pellets, garnet sand, crushed calcite

 Data matrix: (grain size, temperature, water flow)  Validation: data comparison

1 mm

(30)

(31)

 Particles: CaCO₃ pellets, garnet sand, crushed calcite

 Data matrix: (grain size, temperature, water flow)

 Validation: data comparison  10 sieved fractions(0.4 < d_z < 2.0 mm)

 4 temperatures

(5, 15, 25, 35 °C)

 25 ascending water flows

(0-180 m/h)

(32)

o Introduction

o Objectives

o Materials and methods

● Results and discussion

o

Conclusions

(33)

Objective Materials & methods Results & discussionResults & discussion

 Experiments: 76 fluidisation characteristics

 Results: model (implicit) and simplified model (explicit)  Application: drinking water pellet softening

 Model accuracy improvement

(34)

. −

− . = . .

(35)

Introduction Conclusions Questions 34

1 10 1 10 100 1.000 Coef fi ci ent (Ri card so n -Z ak i) [-] Reynolds terminal [-]

n=2.4 (viscous regime) n=4.8 (inertial regime) Richardson-Zaki (1954) Wallis (1969)

Richardson (1971) Garside-AlDibouni (1977) Rowe (1987) Khan and Richardson (1989) RZ-hydr1 (BL+CK) RZ-hydr2 (KZ+LW)

RZ-hydr3 (EG+LW) Rowe-hydr-Ret Calcite pellets (42) Sand pellets (0) Garnet pellets (0) Glass pearls (0) Garnet (13) Calcite IT (0) Calcite UK (0) Calcite NL (0) Calcite NH (20) Crystal sand (0)

(36)

35 0%

5% 10% 15%

20% _{Porosity prediction error} Whole range mf-180 [m/h] 60-90 [m/h] 0% 20% 40% 60% 80% 100%

(37)

minimum fluidisa on >100%→12% porosity >15%→3%

36 0%

5% 10% 15%

20% _{Porosity prediction error} Whole range mf-180 [m/h] 60-90 [m/h] 0% 20% 40% 60% 80% 100%

(38)

o Introduction

o Objectives

o Materials and methods

o Results and discussion

● Conclusions

(39)

Introduction ConclusionsConclusions Questions

 RZ models can be improved based on hydraulics principles i.e. 3 points (ε,v)

(0,0) (ε_mf, v_mf) (ε→1, v_t)

 Porosity can be predicted more accurately

 Recommendations:

• Model enhancement (more general)

• Identification of irregularly shaped particles

• Implications for specific surface area (Interfacial Area Density)

(40)

Introduction ConclusionsConclusions Questions

 RZ models can be improved based on hydraulics principles i.e. 3 points (ε,v) (0,0) (ε_mf, v_mf) (ε→1, v_t)

 Porosity can be predicted more accurately

 Recommendations:

• Model enhancement (more general)

• Identification of irregularly shaped particles

• Implications for specific surface area (Interfacial Area Density)

(41)

o Introduction

o Objectives

o Materials and methods

o Results and discussion

o Conclusions

(42)

DOI: 10.1016/j.powtec.2018.11.018

(43)

Thank you for your attention

(44)

Personalia

Name: Onno Kramer Phone.: 06-42147123

E-mail: onno.kramer@waternet.nl Network: LinkedIn

Publications: TUDelft PureCycle , ResearchGate,

Waternet, Sector Drinking Water, Department, Production

HU University of Applied Sciences Utrecht, Institute for Life Science and Chemistry

Delft University of Technology

Faculty of Civil Engineering and Geosciences, Department Water Management, Section Sanitary Engineering, Research Group Drinking Water Faculty of Mechanical, Maritime and Materials Engineering, Department Process and Energy, Section Intensified Reaction and Separation Systems

(45)

Optional for questions

(46)

(47)

(48)

(49)

(50)

(51)

Rat io: super ficial / te rm inal set tl ing v e loc ity [-] Porosity [m³/m³] n=2.4 inertial regime n=2.6 n=2.8 n=3.0 n=3.2 n=3.4 n=3.6 n=3.8 n=4.0 n=4.2 n=4.4 n=4.6 n=4.8 viscous regime Minimum fluidisation 50

(52)

0,4 0,5 0,6 0,7 0,8 0,9 1,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Porosi ty [m ³/m ³]

Ratio: superficial / terminal settling velocity [-]

n=2.4 inertial regime n=2.6 n=2.8 n=3.0 n=3.2 n=3.4 n=3.6 n=3.8 n=4.0 n=4.2 n=4.4 n=4.6 n=4.8 viscous regime 51

(53)

1 10 1 10 100 1.000 10.000 Coe fficien t (Ricar dso n -Zaki) [-] Reynolds terminal [-] n=2,4 (viscous regime) n=4,8 (inertial regime) Richardson-Zaki (1954) Wallis (1969) Richardson (1971) Garside-AlDibouni (1977) Rowe (1987) Khan-Richardson (1989) RZ-hydr1 (BL+CK) RZ-hydr2 (KZ+LW) RZ-hydr3 (EG+LW) RZ-hydr-Ret Metal balls (RZ) RZ data 0,1 1 0,4 Su pe rf icial ve lo ci ty [m /s] Porosity m³/m³] n(m=1kg)=2.406 n(m=2kg)=2.434 n(m=3kg)=2.415 52

(54)

 Profit: re-use calcite as a seeding material - Cost reduction: 100.000 €/year (0,4%)

- Sustainability: 40.000 eco-points/year (5%)

- Valorisation: high market segments: glass/paper/capet… - Vision: possibilities introduction of process cycles in industry - So much to learn…

- Legislation - Hydraulic

- LCA calculation

The Calcite factory

53

(55)

(56)

(57)

(58)

CFD oppertunities

57 - Interstitial velocity versus terminal settling velocity

- Tortuosity versus ratio terminal and interstitial velocity

- Influence of the geometric representation (shape) on the specific surface area - Particle interactions and collisions versus drag

- Relevant forces buoyancy, gravity and friction - Surface roughness impact

- …

Any suggestions are welcome.

(59)

Improvement of the Richardson-Zaki liquid-solid fluidisation model on the basis of hydraulics (PPT)

Improvement of the Richardson-Zaki

liquid-solid fluidisation model

on the basis of hydraulics

Contents

o

Introduction

o

Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

Contents

● Introduction

o

Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

Contents

o Introduction

● Objectives

o

Materials and methods

o

Results and discussion

o

Conclusions

Contents

o Introduction

o Objectives

● Materials and methods

o

Results and discussion

o

Conclusions

Contents

o Introduction

o Objectives

o Materials and methods

● Results and discussion

o

Conclusions

Contents

o Introduction

o Objectives

o Materials and methods

o Results and discussion

● Conclusions

Contents

o Introduction

o Objectives

o Materials and methods

o Results and discussion

o Conclusions

Thank you for your attention

Optional for questions

CFD oppertunities