Petrobras to use new tech to split oil from CO2 on seabed

Petrobras announced this week it will begin within four years the pilot phase of a new project to re-inject carbon dioxide removed from oil fields underground. Dubbed the Hisep Project, the new technology developed by the company allows the separation of oil from carbon dioxide and the subsequent re-injection of the CO2 to take place on the seabed rather than on the platform.

As it stands today, Petrobras already re-injects part of the CO2 underground. Through the new initiative, the idea is to increase the percentage of re-injection. The method involves liquefying CO2 using underwater equipment that raises the pressure on the gas. In liquid form, the carbon dioxide is re-injected underground, preventing it from being dispersed into the atmosphere.

The project’s pilot phase will be implemented in the pre-salt Mero field, in the Santos basin. After laboratory tests, Petrobras will arrange for the assembly of the underwater equipment that will separate and re-inject the gas. The total investment from the start of the research in 2014 to the kickoff of the pilot phase in mid-2028 should reach $1.7 billion

CO2 is a gas that is associated with oil in underground reservoirs. When oil is extracted, a significant amount of the gas is released into the atmosphere.

De-carbonization

“De-carbonizing the oil business is key to the energy transition. It means we can still use hydrocarbons, oil, and gas in our daily lives—for a long time, we’ll still have to—but with a mitigated impact,” said Petrobras President Jean Paul Prates.

The state-run company, he noted, has been trying to make a responsible energy transition, while at the same time dealing with divergent demands surrounding the pace of these changes. Some sectors of society are calling for more speed in the process, while others want it to be slower, he pointed out.

According to Petrobras Director for Engineering, Technology, and Innovation Carlos Travassos, the initiative could also bring cost savings.

“A large part of the process plant [on oil platforms]—around 65 percent—is dedicated to separating and injecting gas. By using Hisep, I take this operation down [to the seabed]. With a 65 percent reduction in weight and space [on the platform], we expect a significant cost reduction.”

In addition, by reducing the cost of separating and re-injecting carbon dioxide, oil can be extracted from fields that are currently not economically viable due to high CO2 content. Another positive point, Travassos mentioned, is that it reduces the exposure of employees to risk, as it takes the process away from the platform facilities.