NAUTILUS has awarded DRA Group with the contract for the detailed design of the Solwara 1 dewatering plant to be used on the company’s production support vessel.

The scope of work awarded to DRA involves the detailed design of the vessel-mounted material processing facilities.

Nautilus said the design phase is expected to be completed in the fourth quarter 2015.

On completion of the design, the vessel-mounted modules will be fabricated and pre-commissioned onshore prior to integration onto the completed vessel.

Fabrication of the process plant is expected to commence in early 2016, with first production from the Solwara 1 project scheduled for 2018.

With a design capacity of 400 tonnes per hour, the plant will include screening the Seafloor Massive Sulphides into a number of size fractions, followed by dewatering using centrifuges and filter presses, eventually filtering to 8 microns.

The combined dewatered product will then be temporarily stored in the vessel’s hold, prior to shipment via Handimax vessels to the company’s processing partner in China.

Nautilus said the remaining filtered water was then returned via the enclosed riser system to drive the subsea lift pump and discharged within 50 metres of the seafloor from where it originally came.

Nautilus chief executive Mike Johnston said the project team had worked on studies and early engineering with DRA for several years.“DRA has extensive experience with similar floating dewatering/mineral processing facilities in related offshore industries. We are pleased to have them utilise this experience when they carry out the detailed design for our on board processing facilities.”

Pleased with the award, DRA regional director Donald Holley said he looks forward to applying DRA’s previous experience in designing vessel-mounted process plants, particularly learns learnt from the company’s offshore diamond recovery projects in South West Africa to the Solwara 1 project.

DRA is a multi-disciplinary engineering group which delivers mining, minerals processing and infrastructure services from concept to commissioning together with operations and maintenance services.