Cement Australia – Heat Exchanger Duct Replacement

Cement Australia’s operations in Gladstone incorporate Australia’s largest cement kiln, capable of producing more than 1.6Mtpa of cement.

Early in 2017, it was identified that the heat exchanger duct between the clinker cooler and the inlet to heat exchanger no.1 (HE1) had reached the end of its life, and was significantly impacting on plant production. Cement Australia engaged Walz Group to replace the equipment to return the kiln performance to full capacity. The project required us to remove and replace the failing heat exchanger, ductwork, inlet chamber, associated supports, and specified tubes during a time critical shutdown.

We utilised our dedicated fabrication facility to manufacture all the ductwork, inlet chamber, and the associated supports and components. We also applied protective coating as required. Prior to the shutdown for the replacement works, we reinforced the plant foundation and structure to ensure it could accommodate additional loads.

Our comprehensive plant and equipment fleet was invaluable for this project, which required craneage and scaffolding to remove and replace the existing structure.

BMA Broadmeadow – MG10 & MG11 Conveyors

As BMA’s Broadmeadow longwall mine operations advanced, a need was identified to install new conveyer infrastructure to replace shuttle cars and diesel ram cars to transport coal from the face.

Walz Group was engaged by BMA to complete the structural, mechanical and pipework installation of two new conveyers — Maingate 10 (MG10) and Maingate 11 (MG11). The project was completed in two stages — one for each conveyor — to accommodate operational constraints. We undertook all installation and construction work required to complete both conveyors.

Works were conducted in a live operating environment to maximise operational efficiency. This required careful planning and sequencing to ensure the mine could continue to operate as usual, safely and with minimal impact on production.

Specifically, the works incorporated:

Coffin seals
Drive frames
Drive modules
Belt maintenance equipment
Substation shed and related interface structures
Grouting to all structures including drive areas and transfer foundations
Hand rails
Transfer towers
Gantries and trestles and their associated mechanical components

Leighton – APLNG Curtis Island Workers Camp

Forming part of the six LNG trains on Curtis Island, the Australia Pacific LNG plant is Australia’s largest producer of coal seam gas (CSG). It not only supplies Queensland’s domestic gas market, but also processes CSG into liquefied natural gas to meet the demand of customers around Australia and globally. The development of the plant took some five years, shipping its first cargo in 2016.

To support the construction of the plant, Walz Group was engaged by Leighton Contractors (now known as CPB Contractors) late in 2011 to build the works accommodation camp. Our scope incorporated:

Civil Works including
- Preparation of site
- Road construction
- Building platforms
- Drainage
- Concrete works
Building installation
- 2,600 residential units
- Full commercial kitchen and dining hall to accommodate preparation of three meals a day for 2600 camp residents.
- Miscellaneous buildings including offices, gymnasiums, laundry/toilet/washroom blocks, medical facilities, lunch cribs, security huts, etc
- BBQ shelters, pavilions, walkways

John Holland – Abbot Point X50 Expansion

We worked with John Holland Group to deliver the X50 Expansion at Abbot Point Coal Terminal. This work increased the North Queensland Bulk Ports Corporation’s annual export capacity to 50 megatonnes. The facility services the export requirements of a number of mine operators, including Newlands, Collinsville, and Sonoma mines.

Our scope incorporated a range of marine works associated with the extension of the transfer tower and construction of the additional operation berth, east of the existing Berth 1. The works included installation of piles, headstocks, and rail girders, as well as steelwork modifications, installation of new equipment, and modification of existing equipment to accommodate the expansion. Walz provided all associated marine equipment and qualified operators.

Newcrest – Tank TK202 Repair

Newcrest Mining Limited (formerly Lihir Gold Limited) operates a gold mine and processing facility on Lihir Island in Papua New Guinea. Two Heavy Fuel Oil (HFO) storage tanks (TK201 & 202) were constructed for the original plant in 1996 and one new IPS HFO storage tank was later commissioned in 2013. TK201 and 202 were originally designed and constructed to API 650 for a nominal storage capacity of 14,000l each.

Following maintenance inspections on TK202 in 2009 and later in 2012, Newcrest identified various repairs and upgrades required to ensure the tank maintained its compliance. Walz Group was engaged to assist with this scope of works which included:

Internal inspection of the tank
Repairs to the tank’s annular ring, shell, roof and tank furnishings
Repairs to the tank’s internals including floor, support columns and roof framing
Repairs to protective coatings

Newcrest – Automated Ball Feeder

With a history of successful collaboration at the Lihir gold mine, working on the repair of HFO storage tanks TK01 and TK02, we were pleased to partner with Newcrest again for these improvement works to the mine’s gold processing plant. Walz was engaged to carry out the SMP and Electrical and Instrumentation works associated with upgrading three of the automated feeders on the existing ball mills at the plant.

Our scope included installation of structural steel and mechanical components (storage bin, air multipliers, feed tubes, hoists, magnets, discharge hoppers, feed launders and head box). We also performed the associated piping works required to upgrade the ball feeders. The Electrical and Instrumentation works were carried out by a specialist contractor from Australia, selected and engaged by us. We mobilised some of our plant and equipment to Lihir from Gladstone to assist with these works.

Having carried out several projects in Lihir, we recognise the importance of community engagement and always seek to engage local labour hire and subcontractors whenever we work on the island.

BMA Hay Point – Trestle Deconstruction

Based on our successful track record on multiple projects at Hay Point terminal, we were engaged by BMA to deconstruct and remove the original trestle and the 17BP conveyor installed when the facility opened in 1971. The ageing 1.8km structure transported coal from the terminal to waiting bulk carriers for more than 40 years and was decommissioned late in 2016.

Working from jack-up barges, our crews are dismantling the trestle and conveyor in sections, and transferring approximately 6,500 tonnes of steel to Half Tide Harbour by barge. Our work at Hay Point is ensuring that aging infrastructure is safely and carefully removed in order to best protect the local environment. In March 2019, Walz Group achieved two years recordable injury free on the project.

In conjunction with the main work of dismantling the trestle, Walz Group is undertaking additional separable portions of work under the same contract. Each separable portion of work is outlined below.

Disposal of Waste Material

Once on-shore, the trestle sections are separated into steel, concrete and timber components and prepared for transport to recycling facilities.

Dewatering and Processing of Pile Water

If the water located in the piles is not inert or has the potential to cause visual pollution, Walz is responsible for processing and filtering the water prior to release off-site.

TT8 Top Deck Removal

We are removing and disposing of the existing TT8 top deck, and installing the new structure and supporting componentry.

Berth 1 to MD2 Footbridge Installation

We have been contracted to install a new footbridge (Footbridge 2), with associated structural support and access walkways. The new structure will connect Berth 1 to MD2 after the deconstruction of 17BP conveyor and roadway.

Berth 2 Shutdown Works

The current shiploader infrastructure requires upgrading and refurbishment, as well as installation of new elements. We have completed:

Fender maintenance and chain replacements
Installation of a new davit crane
Upgrading the ship access gangway and supporting structures
Removal of redundant fenders
Other miscellaneous works as required

Berth 1 Shutdown Works

This refurbishment work is similar in nature to that outline for Berth 2 above and incorporates:

Fabrication and installation of a new tripper
Installation of new transfer chute and upgraded pulleys
Repair and surface protection to conveyor structure and rail girders
Supply and installation of new tripper rail
Installation of new walkways between berthing dolphins
Installation of new top Davit Crane
Fender chain replacements

Ausenco – Carborough Downs Overland Conveyor

Vale’s Carborough Downs underground mine is located in Central Queensland’s Bowen Basin, 180 kilometres southwest of Mackay. Walz Group was engaged to perform the structural, mechanical, piping, and electrical installation of the 5km overland conveyor and upgrade of the coal handling and preparation plant (CHPP). This formed part of a broader brownfields expansion. In total, we constructed almost 6km of conveyor systems (drift, stockpile, reclaim, reflect, overland and surge bin conveyors) and associated componentry.

Our works included:

Structural steel installation — trestles, conveyor gantries, transfer stations
Mechanical installation — belt weighers, scrapers, drive motors, pullies, external gravity take-up
Installation of victaulic and screwed pipework
All electrical installation

BMA Hay Point – Stacker Reclaimer SR1 & SR2 Refurbishment

When the existing stacker-reclaimer stockyard machines (SR1 and SR2) at the Hay Point coal terminal started to approach the end of their life, BMA commenced the process of replacing them. With an anticipated lead time of two years for the new equipment to be manufactured and shipped to Australia, the machines needed work to be kept operational until the replacements arrived.

Walz Group was contracted to dismantle both stacker-reclaimers down to the fixed cone to undertake structural integrity repairs. This would extend the life of both machines for the interim lead time of their replacements. The works involved removal of mast, pendants, bucket wheel boom, counterweight arm, counterweight box and slew cone.

The machines were then rebuilt with new slew cone, new counterweight assembly and refurbished bucket wheel boom. Both machines were jacked up to clear the rails to remove all bogies, which had to be refurbished and machined to suit the new rail profile.

Our fabrication workshop and protective coatings workshops Gladstone were instrumental in the repair and refurbishment of existing componentry.

Alcan Grove – Transfer Station TS6-10 Dust Handling System

Rio Tinto’s Alcan Gove operations are located on the Gove Peninsular in northeast Arnhem Land in the Northern Territory. Our client identified that the plant was experiencing product loss and dust emissions at a juncture of two conveyors transporting ore to the harbour. The dust emission issues were due to inefficiencies within the transfer station. Walz Group was engaged to upgrade the export conveyor system and transfer station to achieve a targeted reduction in visible dust generation of 85%.

Our scope comprised the installation of all structural, mechanical, and piping elements of a new dust handling system. The works included:

Roof modifications
New compressor house
Low pressure air system
Compressed sir system
Dust collector (bag house) and associated ducting
Load station and associated return air slides
Head chute