Dredging 101. Why, Who, How and So What! 2015 WAMSI Research Conference. 30 March 2015

Transcription

1 Dredging 101 Why, Who, How and So What! 2015 WAMSI Research Conference 30 March 2015

2 Presentation Contents Quick Oversight on Why we need to Dredge and Who Carries it out Global Context of some of our Projects How Dredges work and their Turbidity Generating Sources

3 Things Have Changed (improved?) Drilling Rock by hand ready for blasting, Swan River Mouth, now Fremantle Inner Harbour

4 Why? ~30% GDP for Australia generated via seaborne trade 1 Shipping Channels, like roads, need to be maintained and improved Dredging of shipping channels, for maintenance and capital deepening is necessary Dredging also required for other maritime development activities References: 1 Ports Australia, April 2014 Dredging and Australian Ports

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6 Global Shipping Fleet is Growing in Size Sourced from Ports Australia

7 Who? A number of domestic players, generally with smaller sized equipment suited to minor capital and maintenance dredging projects Only five key International Companies who have recent track record to directly execute projects in Australia under our contracting, HSE and IR conditions o A couple of companies have completed works as part of a JV or sub contract For large projects proponents are competing globally for a limited fleet of equipment we generally can t pick and choose

8 International Trailer Suction Hopper Dredge Fleet Global Fleet Potentially Available to Australian Market Hopper Capacity (m 3 )

9 International Cutter Suction Dredge Fleet Global CSD Fleet Potentially Available to Australia Total Installed kw

10 So What? Recent Large Capital Dredging Projects-Australia Location Volume Dredged Duration Ichthys (NT) 16Mm3 ~14months Ichthys (NT) 16 Mm 3 14 months Gladstone (Qld) 25Mm3 Gladstone (Qld) 36 Mm 3 28 months Gorgon (WA) 8Mm3 Gorgon (WA) 8 Mm 3 6 months Wheatstone 25Mm3 Wheatstone (WA) 25 Mm 3 25 months Port Hedland (south west creek) (WA) 14 Mm 3 12 months Totals ~100Mm 3 ~85 months (100 Subiaco Football Stadiums)

11 Recent Capital Projects and Scale - Global Suez Canal Channel Duplication: 230Mm 3 of Dredging over 50km of Channel 17 Cutter Suction Dredges and 2 Trailer Suction Hopper Dredges Contract Signed October 2014, started soon after and to be completed by August 2015 (i.e. <10 months)! Panama Canal Expansion 1 ~ 60Mm 3 of Dredging and excavation on the Atlantic, Pacific Entrances and Gatun Lake References: 1

12 How - Types of dredgers Hydraulic (slurry formed to transport material) Mechanical (near insitu density removal) Cutter Suction Dredge Trailer Suction Hopper Dredge Water Injection Dredge Backhoe Dredge Grab/Clamshell Dredge Dipper Dredge Bucket Ladder Dredge Suction Dredge

13 CSD Typical Features Deck Crane Bridge Side Anchors Working/ Travelling Spud Fixed Spud Slurry Pumps + Pipework Suction Mouth Ladder Cutter Head Source: IADC Dredging for Development,

14 Cutter Suction Dredges Small and Large

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16 Ground anchors Delta flippers (sand) Bruce Danforth Stevin Stevsharks (rock)

17 Gravity anchors Box anchors Concrete block Tripod platform?

18 Placement anchor booms

19 Cutting Teeth Before, and After

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21 Blade Tooth Adaptor

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23 Reclamation Areas In Theory

24 Reclamation Area In Practice Dredge Material Discharge Point Dredge and Pipeline Internal Bund Tailwater Discharge Point External Bund

25 Weir Boxes

26 Reclamation Area Lined

27 Trailer Suction Hopper Dredge

28 Bridge and Accommodation Draghead Suction Pipe Hopper Pump Ashore Connection

29 TSHD Dredging Cycle Hopper Overflow Losses Propellor Wash Draghead DREDGING SAILING LOADED TO DISPOSAL SITE Propellor Wash Propellor Wash SAILING EMPTY TO RECOMMENCE DREDGING DUMPING MATERIAL/ PUMPING ASHORE Fines Stripping from Dumped Material Fines within Tailwater Discharge Propellor Wash

30 Bridge Operations

31 Turbidity Hopper Overflow during dredging

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34 TSHD - Draghead

35 Turtle Exclusion Chains

36 Loaded and Travelling to Disposal Site

37 TSHD Bottom Dumping via Split Hopper

38 TSHD Bottom Dumping via Doors

39 Plume Generation Bottom Dumping

40 Beach Renourishment Pumping Out

41 Backhoe and Grab Dredges

42 Backhoe Dredge

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44 Backhoe Dredge

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46 Online Resources PIANC CEDA (Central Dredging Association) - IADC (International Association of Dredging Companies) US Army Corp of Engineers - IHC Dredging -