Abu Dhabi Polymers Company (Borouge) is inviting contractors to bid for three construction deals worth $4.5bn in total as part of the third-phase expansion of its petrochemicals complex at Ruwais.

Borouge approached contractors to bid for the three engineering, procurement and construction (EPC) contracts in the third week of October, according to prequalified firms. The companies first expressed interest in the deals on 17 September.

 The third-phase expansion of the complex, the Borouge 3 project, will boost the firm’s plastics production at Ruwais by 2.5 million tonnes a year (t/y) to 4.5 million t/y, making it the largest complex of its kind in the world. The complex currently produces only 600,000 t/y but this is being expanded to 2 million t/y under the Borouge 2 project, which will be completed in 2010.

The first contract to be tendered for Borouge 3 is a $3bn deal to expand polyolefins production by building reactors, an ethylene purification unit and a catalyst system. Borouge has invited at least six firms to bid.

The second deal is a $1bn offsites and utilities package to supply seawater-cooling systems, chemical and oil product storage systems, and construct the main buildings at the site.

The third contract, worth $500m, is to build a low-density polyethylene plant. Polyethylene is used to make piping.

In July, Borouge awarded a $1.1bn contract to build a cracker to Germany’s Linde.

In the same month, it awarded the front-end engineering and design contract for the three construction packages to Italy’s Tecnimont.