Oil from offshore wells: IIT Madras has got technique

The Indian Institute of Technology Madras is in the process of developing indigenous processes for efficient recovery of oil from mature offshore wells.

In India, domestic crude oil production is currently insufficient to meet the nation’s energy demands. Last year, the Government of India approved fiscal incentives for enhancing oil and gas recovery from ageing and new fields, which can potentially raise the production of oil by 120 million tonnes.

Collaborating with research laboratories in Australia, IIT Madras researchers are studying the efficacy of an emerging enhanced oil recovery method called ‘Low-Salinity Enhanced Oil Recovery’ (LSEOR).

Their findings have recently been published in two journals – Journal of Petroleum Science and Engineering and Energy and Fuels.

The Research is being headed by Dr Jitendra Sangwai, Department of Ocean Engineering, IIT Madras, who studies state-of-art processes used to recover crude oil from offshore reservoirs in India.

His research is being funded by IIT Madras and Department of Science and Technology (DST), Government of India.

In line with this expectation, Oil and Natural Gas Corp (ONGC) has been looking at Enhanced Oil Recovery (EOR) techniques to boost oil and gas output from old and matured fields.

Leveraging on modern techniques such as LSEOR could enable the country to meet the expected output. Researches such as those conducted by Dr Sangwai’s laboratory can help understand and optimize the technique and develop indigenous processes for efficient recovery of oil from mature offshore wells in India.

In a press statement, Sangwai said, “Our research aims to develop indigenous methods for recovery of crude oil from geological reservoirs, which is a complex process. There is still much that needs to be understood in the use of LSEOR methods. We do not yet have a clear idea on the mechanism of wettability alteration that can be caused by factors such as oil composition, salt levels in the water, the acidity of the crude oil, mineralogy of the rock and other factors.”

In a paper published recently in Energy and Fuels, Dr Sangwai and his research student, Abhijit Kakati reported that a reduced concentration of divalent cations such as calcium and magnesium in water can make the quartz less oil wettable, while sodium ions seem to have the opposite effect. Similarly, the presence of acidic and basic substances in the oil also reduced water wettability, especially in the presence of salts.

In a parallel study, Dr Sangwai’s team, along with his research student Nilesh Jha, has also studied the effect of adding surfactants and nanoparticles to low salinity water to alter the wettability of sandstone. Surfactants can reduce the interfacial tension between the oil and water, and therefore make the rock more water wettable, but the surfactant itself can be absorbed by the rock.