SoluForce helps energize Fiji with submarine LPG pipe

Fiji is an island country, an archipelago in the heart of the Pacific Ocean. Due to its location and setup, it is heavily dependent on imported fossil fuel to cover a great part of its energy needs. To increase the accessibility to liquified petroleum gas (LPG) for end customers, Bluegas, a locally owned family company invested into an LPG terminal at their Baro, Lami, site on Viti Levu. Requiring a safe, fast and easily installed off- and onshore gas pipe connection, Bluegas got granular on several available options and finally chose a long length SoluForce RTP (Reinforced Thermoplastic Pipes) solution.

FOSSILE ENERGY DEPENDENCY

Although Fiji consists of about 300 dispersed volcanic islands, only a third are inhabited and a major part of the country’s population (~853,000) as well as its economic activities are concentrated on the two main islands Viti Levu and Vanua Levu. It counts amongst the small island developing states (SIDS) in the Pacific and is, due to its geographical location and setup, forced to import fossil fuel to cover most of its energy needed for domestic, commercial and industrial applications as well as transportation. Liquified petroleum gas (LPG), unleaded petroleum, diesel, kerosene, and premix are imported from Australia, New Zealand and Singapore with tankers. It goes without saying, that the dependency on imports leaves the country to struggle with high energy prices and energy security in general.

INCREASED ACCESSIBILITY TO LPG WITH A NEW TERMINAL

To facilitate and increase end customers’ accessibility to LPG for comparably more efficient and apparently safer cooking, heating and warm water, the supplier Petroleum and Gas Co (Fiji) PTE Limited t/a Bluegas, a 100% locally owned family company and subsidiary of the Hari Punja Group, decided to invest in the establishment of the Baro LPG terminal at the company’s Lami site. An offshore loading platform around 700 meters from the terminal will allow for tankers to connect and pump LPG directly to the onshore facilities comprising piping reticulation, road-tanker filling station, gas cylinder filling station, as well as fire protection systems, workshops and other ancillary services.

TIME AND SAFETY INFLUENCE PIPE SELECTION

In search of an adequate submarine pipe for safely transporting the LPG from the offshore tanker platform to the on-shore facility piping Bluegas contracted Zeus Engineering Ltd to compare several alternatives in an extensive feasibility study. The most dominant preconditions were set by time, so that alongside safety and longevity, quick delivery and fast installation were dominant criteria. Apart from a relatively near-term offshore lease expiry which ruled out long lead times, complicated design and time-intense laying. The changeable local meteorological conditions that can be encountered in the region emphasized the need for quick installation.

“A short installation timeline translates also to lower installation costs. Apart from this, it was important to us to have a robust pipeline with a service life guarantee and zero maintenance solution. The design surpassed the standard requirements in terms of seismic and process compliance”, say Shivam Rajan Naidu, CEO of Zeus Group and Ajai K. Punja, Managing Director at Petroleum & Gas Co. (Fiji) Ltd.

“SoluForce RTP pipes are flexible and are produced in long lengths up to 400 meters per reel. Transportation is very economic this way – only 3 coils had to be shipped to Baro – and more importantly, the long pipe length and flexibility enable a straightforward design saving on a lot of time-intense connections”, says Mark Bruin, Technical Service Engineer at SoluForce. With a long track record in supplying infrastructure solutions for the oil and gas industry, and a service life of 20 years without additional corrosion protection, SoluForce GT (gas tight) composite pipes presented the ideal solution for Fiji’s new Baro Terminal.

A later feasibility study by Zeus Engineering confirmed the choice also from a system performance perspective: Whereas other available options considered in the study would have led to capacity reductions or necessitate an increase in pipe diameter to counteract pressure loss, the SoluForce M570 GT pipe system provides optimal, uncompromising performance.

STRAIGHTFORWARD PIPE DESIGN

Thanks to the flexibility of the gas-tight pipe, the fact that it is delivered in long lengths, its easy installation, and the material’s insensitivity to the corrosive submarine environment, the pipeline route was simple and straightforward and involved two pipe joints only.

Starting from the tanker platform where the line is clamped to the vertical platform pillar it then takes a 90° bend at a minimum of 3-meter-radius progressing beneath the seabed in a straight line towards the coast. At the coast, the pipe takes a second, softer bend up the coastal area, creating a slope to finally transition into the onshore trench.

SUBMARINE PIPE INSTALLATION

In preparation for a safe and fast installation of the pipeline, works involving the opening of the sea wall and trenching were conducted a couple of days earlier. To ensure a smooth pipe installation procedure, a SoluForce Engineer arrived on site to accompany and support Dive Centre, a local contractor specialized in submarine pipe and cable installation.

While the SoluForce pipe was unspooled bit by bit, it was pulled from the onshore site into the water using a small excavator. A small boat steered the end of the pipe. After the first 400 meters of pipe had been uncoiled, the consequent segment was swiftly connected with a pre-mounted SoluForce P2P coupling. To save on time, equipment and most of the welding, all fittings had been pre-welded at the SoluForce Factory. Only the last EF-end connecting to the onshore facility pipe had to be welded on site to be able to cut the line at the required length.

Crossing various zones, including a surf zone, and with expected marine activity, it was important to bury the complete line for safety reasons but also to protect the pipe from physical stress caused by the harsh marine environment. The trench with an average depth of 1.2 meters was created by sandblasting.

In addition to adequate backfill material, locally produced rectangular ballast blocks were used to weigh down the line and keep it in place. “The necessary size and weight of these concrete blocks depends heavily on the local circumstances and needs to be calculated for each project”, says Peter Cloos, Head of Technical Service Department at SoluForce, and adds “We are here to support our clients with these kinds of calculations. Marine environments are very harsh and it’s important to carefully plan and prepare ahead to ensure the longest possible, untroubled service life. The toughest pipe will fail at some point if improperly installed, and this is why Bluegas selected only very experienced companies.”

To avoid any physical damage from wave action carrying debris, liquified backfill material, and the sea wall, a PE pipe was utilized as protective sleeve for the section around the sea wall.

The complete pipe installation procedure including clamping the pipe to the tanker platform and welding the end fitting to connect to the onshore structure took only 2 days.

FINAL TESTING

Once the pipe had been successfully installed the pipeline went through a hydrotest which SoluForce had provided, to ensure the system’s tightness. Water was used to push a pipe PIG through the line to clean the inside of the pipe and at the same time fill it up with water. Then the water was put under pressure for 1 hour as defined in the requirements. As final verification a final hydrotest has been conducted with success 2.5 weeks later.

“At SoluForce we are used to working on challenging projects – this was no exception as there were very specific requirements that needed to be taken care of. The success of this project is certainly indicative of the smooth collaboration between our sales and technical departments, the customer, and the engineering firm. And apart from being proud of yet another successfully completed project, we are also proud to have played a key role in improving the energy situation for this remote island’s community”, concludes Robert-Jan Berg, Managing Director at SoluForce.  

1 Petroleum & Gas Company (Fiji) Limited T/A Bluegas