Becoming bi-directional: SWQP reconfiguration

Skid installation at Wallumbilla.

Skid installation at Wallumbilla.

Gas Today takes an in-depth look at APA Group’s construction approach to the Easternhaul Project, which involves the reconfiguration of the South West Queensland Pipeline to provide bi-directional flow and is being executed across three existing operating facilities.

In December 2012, following APA Group’s acquisition of Hastings Diversified Utilities Fund, including Epic Energy’s South West Queensland Pipeline (SWQP), APA Group undertook a detailed due diligence exercise on in-flight projects commenced by Epic Energy on the SWQP. Epic Energy had executed a number of agreements to transport Cooper Basin gas from Moomba to Wallumbilla for supply to LNG producers at Gladstone. This required the reconfiguration of the SWQP to provide flow in an easterly direction whilst maintaining the ability to flow in a westerly direction for existing users, hence the project has become known as the Easternhaul Project.

The project is being undertaken to respond to changing market requirements in the region, enabling Cooper Basin gas to flow in an easterly direction for delivery to the LNG producers at Gladstone. In addition to allowing Cooper Basin gas to be supplied to Brisbane and Gladstone, the SWQP bi-directional flow capacity will allow gas from the Bowen and Surat basins to be supplied to southern markets. The SWQP will be able to reverse direction at any time and be able to flow at its maximum capacity in either direction within a few hours.

The Easternhaul Project is unique as it is being executed across three existing operating facilities. The new facilities involve significant piping, valving, instrumentation and controls, and integration of new major equipment into existing operating facilities, which makes the construction, pre-commissioning and start-up more challenging. The project has multiple completion packages and completion dates for various proponents, resulting in multiple construction completion and commissioning phases.

The SWQP forms a key link between four existing APA pipelines – Roma to Brisbane Pipeline; Berwyndale to Wallumbilla Pipeline; Carpentaria Gas Pipeline and the
Moomba to Sydney Pipeline. This linchpin asset created a 7,000 km gas pipeline grid transforming the eastern Australian gas market by allowing gas to move seamlessly across four states and the Australian Capital Territory under a single transportation contract. The additional flexible gas transportation and storage services that APA’s Easternhaul Project will add to the east coast gas grid will assist customers in managing the variability and complexity of their supply and demand requirements, as well as assist in the development of a competitive gas market in eastern Australia.

Contracting strategy

Due to the tight project timelines, various construction locations and several facility delivery dates, the construction was broken down into multiple construction contracts. Because the new facilities are being integrated into existing facilities, elements of the electrical, instrumentation and controls detailed design and engineering were undertaken in-house by APA.

Procurement included tendering and award of procurement orders, and construction and supply contracts.

Engineering and construction considerations

The significant engineering challenge associated with the SWQP reconfiguration has been to ensure that the facilities provide functional and safe operation under the multiple flow regimes possible with the complex arrangement of pipeline systems, multiple flow directions and flow rates required across the SWQP network. Besides the design of the new facilities involved, the engineering also required review and analysis of the existing facilities for functional and safe operation.

The project underwent a significant number of hazard and operability assessments, which were implemented to identify and evaluate risks to personnel or equipment and to ensure efficient operations. Numerous hazard identification assessments and safety integrity level assessments were also employed.

The construction of the new facilities at three sites involved construction activities within existing operating facilities.

This required the development of detailed permit-to-work management plans, close management and monitoring of construction activities within the facilities and very close communication and co-operation between the project and APA operations to ensure that all works were executed safely and without incident.

Detailed plans have been developed for multiple shutdowns of existing facilities to enable tie-in and commissioning of the new facilities while minimising impacts on existing operations and commercial commitments.

With the project being delivered across three sites with multiple contractors and multiple delivery dates, there has been a significant effort to ensure safe delivery of the project while maintaining seamless services.

Easternhaul Project Overview

The Easternhaul Project involves the design, procurement, construction and commissioning of modifications to the existing SWQP to enable bi-directional flow.
This requires major works at Moomba, Wallumbilla and at the Queensland Compressor Station 4 (QCS4/SS4) located near Cooladdie at the midline of the SWQP.

Moomba, South Australia

    • A new pressure reduction facility and low-pressure header to facilitate the receipt of gas from the Moomba Gas Plant and to manage the transition from eastern to western flow in the SWQP.
    • A new interconnect pipeline between the Moomba Gas Plant and APA’s Moomba compound to allow gas to be received into the SWQP from the Moomba Gas Plant.
    • New connections within Moomba Pressure Reduction Station to deliver gas to the Moomba Sydney Pipeline and Moomba Compressor Station.
    • New facilities to facilitate bi-directional flow on SWQP.
    • Site works commenced in late 2012 and commissioning is scheduled for August 2014.
  • QCS4, SWQP Midline Compressor Station at Cooladdie

     

    • Modification of the existing scraper compound and the installation of switching valves to allow bi-directional operation of the existing compressor station.
    • Associated piping, electrical, instrumentation and controls modifications to existing facilities to integrate the new facilities.
    • Site works commenced in September 2013 and commissioning was completed in February 2014.
  • Wallumbilla, Queensland

     

    • Inlet filter separator for filtering of Easternhaul gas prior to entry into the facility.
    • Multiple new metering and flow control facilities for metering of new receipt and delivery points.
    • Multiple regulation skids for the control and redirection of flows with the Wallumbilla compound.
    • Multiple gas quality monitoring facilities for new receipt and delivery points.
    • Associated piping, electrical, instrumentation and controls modifications to integrate with existing receipt, delivery point and compression facilities whilst maintaining existing westernhaul functionality.
    • Site works commenced in January 2014 and commissioning is scheduled for completion in October 2014.

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