ONGC to turn seawater to fresh water off Mumbai

Vol 23, PW 2 (14 Nov 19) Exploration & Production

'Water, water everywhere' but not a drop for drilling, the British romantic poet Samuel Taylor Coleridge might have mused if he had witnessed ONGC's struggle to secure enough fresh water for its Mumbai offshore activity.

But ONGC has come up with a novel solution to hire two platform supply vessels (PSVs) with onboard desalination units that can convert seawater to fresh water for use in drilling and other non-drinking uses like showering or washing clothes aboard rigs off the west coast. This is the first time ONGC is hiring stand-alone offshore desalination vessels with a pre-bid planned for November 19, postponed from November 5.

Likewise, the bid deadline has been extended from December 4 to December 17. ONGC's problem stems mainly from local authorities who often supply much less than contracted to its Nhava shore base, disrupting deliveries to 32 rigs and 12 process platforms working off Mumbai.

Worse, water is also stolen by local villagers who tap the delivery pipeline to ONGC's shore base. ONGC wants each PSV equipped to produce 600 t/d of fresh water on five-year contracts.

Expect bids from Greatship, SCI, Hind Offshore and other PSV suppliers who will have to partner reputable water treatment companies. Alfa Laval or Rochem India are two such companies.

Each desalination unit is expected to cost approximately $2m and operating expenses will be "very high" with PSV day rates expected to be near $14,000.