The use of Appropriate Technology in the design of new dredgers ir.Robby de Backer, ir.Frederik Deroo Jan De Nul N.V.

The use of Appropriate Technology in the design of new dredgers

ir.Robby de Backer, ir.Frederik DerooJan De Nul N.V.

APPROPRIATE TECHNOLOGY:

Technology or engineering that takes special consideration of its social and environmental ramifications.

Traditional view:

• Simple, efficient technology, using limited resources.

• Immediately applicable in daily life.

• Mostly applied to developing countries.



Applied to Dredging.

• Use design, materials and equipments with lowest possible social and environmental negative impact in the design and construction of Dredgers.

• Use design, materials and equipments with lowest possible social and environmental negative impact during the operation of Dredgers.

• Use operational methods with lowest possible social and environmental negative impact during execution of the project.




Compliance with the principles of Appropriate Technology

• Holistic approach.

• AT = Efficient Dredgers (social aspect ?)

Investment plan 2007-2011(ordered)

PROJECT NR. DESCRIPTION SHIPYARD

8023 7500 m3 Hopperdredger “AL-IDRISI” Buyoung, Korea

8030 7500 m3 Hopperdredger “VITUS BERING” Buyoung, Korea

8025 46000 m3 Hopperdredger “CRISTOBAL COLON” La Naval, Spain

8031 46000 m3 Hopperdredger “LEIV EIRIKSSON” La Naval, Spain

8064 Self-propelled Cutter Suction Dredger (23 500 kW) “IBN BATTUTA” Uljanik, Croatia

8065 Self-propelled Cutter Suction Dredger (23 500 kW) “ZHENG HE” Uljanik, Croatia

8066 Self-propelled Cutter Suction Dredger (23 500 kW) “FERNAO DE MAGALHAES”

Uljanik, Croatia

8067 Self-propelled Cutter Suction Dredger (23 500 kW) Uljanik, Croatia

8474 Backhoe Dredger (3700 kW) “POSTNIK YAKOVLEV” Xinhe Tianjin, China

8623 Side Stone Dumping Vessel (6000 ton) “WILLEM DE VLAMINGH” Buyoung, Korea

8576

8577

3700 m3 Splitbarges (2 units) “BOUSSOLE”, “ASTROLABE” Xinhe Tianjin, China

8578 to 8581 1800 m3 Splitbarges (4 units) “CONCEPCION”, “SANTIAGO”, “TRINIDAD”, “VICTORIA”

Xinhe Tianjin, China

8032 3700 m3 Splithopperdredger “DE LAPEROUSE” Xinhe Tianjin, China

8622 Fallpipe & mining Vessel (30 000 ton) “SIMON STEVIN” La Naval, Spain

8033 3400 m3 Hopperdredger “ALVAR NUNEZ CABECA DE VACA” Xinhe Tianjin, China

8034 3400 m3 Hopperdredger “SEBASTIANO CABOTO” Xinhe Tianjin, China

8035 30500 m3 Hopperdredger La Naval, Spain

8582 to 8585 3700 m3 Splitbarges (4 units) Xinhe Tianjin, China




• Design and construction of a Dredger.– Conceptual design.– Material selection.– System design.– Energy & emissions.

• Operational methods of a Dredger.– Optimal fleet management.– Rules & regulations.– Cost.




Design and construction of a dredger:

• Conceptual Design: EFFICIENCY, APPLICATION OF MODERN DESIGN TOOLS, ADVANTAGE OF “YOUNGER” VESSELS

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

1975 1980 1985 1990 1995 2000 2005 2010 2015

Building Year

Sp

ecif

ic p

ow

er [

kW/k

n*t

on

]

Specific Power [kW/kn*ton] for hopperdredgers 2000 to 5000 m3

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

1996 1998 2000 2002 2004 2006 2008 2010 2012

Building Year

Sp

ecif

ic P

ow

er [

kW/k

n*t

on

]

Specific Power [kW/kn*ton] for Jumbo hopperdredgers

Ratio Deadweight/Light Ship Weight for Jumbo Hopperdredgers

0

0.5

1

1.5

2

2.5

3

3.5

1996 1998 2000 2002 2004 2006 2008 2010 2012

Building Year

Ra

tio

De

ad

we

igh

t/L

igh

t S

hip

We

igh

t

Ratio Light Ship Weight/L*B*H for Jumbo Hopperdredgers

0

0.05

0.1

0.15

0.2

0.25

0.3

1996 1998 2000 2002 2004 2006 2008 2010 2012

Building Year

Rat

io L

igh

t S

hip

Wei

gh

t/L

*B*H

[to

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• Conceptual Design: EFFICIENCY, APPLICATION OF MODERN DESIGN TOOLS , ADVANTAGE OF “YOUNGER” VESSELS

• Material Selection: CRITERIA FOR “AT” COMPLIANCE ARE REQUIRED







• System Design: EFFICIENCY







• System Design: EFFICIENCY

• Energy & Emissions: EFFICIENCY




Operation of a Dredger:

• Optimal fleet management: USE THE MOST APPROPRIATE DREDGER

Vessel A B C

Hopper Capacity [m3] 11300 7500 4400

Dredging draught [m] 9.10 8.15 7.30

Deadweight at dredging draught [ton]

18600 11800 8130

Project parametersDredged spoil: medium to fine sand, D50=150 mu

Dredging depth: 15 mSailing distance from dredge site to disposal site: 15 Nautical MilesDisposal method: Bottomdoor dumpingTotal amount of spoil to be dredged: 1 000 000 m3 Maximum loaded draught due to local constraints: 8 m

Vessel A B C

Weekly production

100% 75% 48%

Cost 100% 91% 120%

Project duration 100% 133% 206%

Total amount of fuel consumed for

project

100% 83% 96%






• Regulations: “HOLISTIC APPROACH”, USE OBJECTIVE PARAMETERS

Project parametersDredged spoil: medium to fine sand, D50=150 mu

Dredging depth: 15 mSailing distance from dredge site to disposal site: 15 Nautical MilesDisposal method: Bottomdoor dumpingTotal amount of spoil to be dredged: 1 000 000 m3

Vessel A

Hopper Capacity [m3] 11300

Dredging draught [m] 9.10

Deadweight at dredging draught [ton]

18600

Vessel A, loading without

overflowing

Vessel A, loading with overflowing

Weekly production 100% 167%

Cost 100% 61%

Project duration 100% 60%

Total amount of fuel consumed for project

100% 60%






• Regulations: “HOLISTIC APPROACH”

• Cost: “COST” OF SIDE-EFFECTS TO BE TAKEN INTO ACCOUNT ?




CONCLUSIONS

• New design tools needed.

• Holistic principle.

• Importance of a modern, versatile fleet.

The use of Appropriate Technology in the design of new dredgers ir.Robby de Backer, ir.Frederik Deroo Jan De Nul N.V.

Documents

m3 slide

appropriate dredger

efficiency slide

conceptual design

use of appropriate technology

system design

efficient technology

environmental ramifications