The Hindu Business Line : Cairn expects more from Rajasthan field

There is more to Mangala than Cairn Energy cares to admit at this point in time. The company has said that there are a billion barrels of oil in Rajasthan field, of which the company expects to get 400 million barrels out of ground. A recovery factor of 40 per cent is considered pretty good in petroleum engineering, especially considering that the oil under Rajasthan is more viscous and does not flow up the well easily.

But talk to officials, informally, they will tell you the truth — the production from the field could be at least 50 per cent more. That is another 200 million barrels.

Viscous oils will have to be taken out of the ground using methods that are called `enhanced oil recovery', or EOR, techniques.

Cairn Energy officials told Business Line in an informal interaction that in the company's projections presented for the initial public offering, the additional 200 million barrels had not been taken into account.

A senior official said that with use of surfactants and polymer flooding, the ultimate recovery from the Mangala field could go up to 60 per cent, a high figure against any benchmark.

Although the crude in the Gujarat-Rajasthan belt is `heavy', Cairn Energy officials do not believe they would have to go to the extent of in-situ combustion (where they pump air into the well (for oxygen) and ignite part of the oil).

Incidentally, in-situ combustion is practised by ONGC in the Mehsana field of Gujarat— the only place in the country where this EOR technique is used.