MEOR: Recovering Oil from Stripper Wells

Ageing oil wells are a growing challenge for the global oil industry. As reservoirs deplete, declining pressure reduces oil flow, leaving many wells classified as stripper wells, low-producing assets nearing the end of their economic life. Despite this, substantial residual oil remains trapped in these reservoirs. Conventional recovery methods are costly (USD 140,000–200,000 per well) and increasingly ineffective at higher depths and temperatures.

To address this, TERI’s Industrial Biotechnology Programme collaborated with the Institute of Reservoir Studies (IRS) in 1999 to develop Microbial Enhanced Oil Recovery (MEOR). The focus was on engineering resilient microbial consortia capable of surviving extreme reservoir conditions, including temperatures up to 90°C, high pressure, and salinity levels of 4–8%.

After five years of extensive collaborative research, the Institute of Reservoir Studies (IRS) and TERI jointly developed and launched the Microbial Enhanced Oil Recovery (MEOR) technology in 2004. The technology was subsequently validated through laboratory-scale studies conducted at both IRS and TERI.

MEOR has demonstrated effectiveness in enhancing oil recovery from stripper wells by mobilising crude oil trapped within the pore spaces of reservoir rocks, thereby improving overall extraction efficiency.

MEOR uses the “huff-and-puff” technique, where microbes are injected into wells to stimulate oil release. These microbes produce gases (CO₂, methane), biosurfactants, alcohols, and fatty acids that work synergistically to reduce oil viscosity, lower interfacial tension, and mobilize oil trapped in rock pores. This significantly improves sweep efficiency and enhances overall recovery.

Field trials have shown promising results. In Gujarat’s Mehsana fields, oil viscosity was reduced by up to 35 per cent. Large-scale deployment across ONGC and Oil India wells yielded over 43,590 metric tonnes of additional oil within six months.

The success of MEOR led to the formation of ONGC TERI Biotech Ltd (OTBL) for commercialization. Today, the technology is applied across 100+ wells in India and abroad, offering a cost-effective, sustainable solution to extend the life of ageing oil fields.