Petrobras uses carbon capture to increase gas production, raising sustainability issues Ship’s crew

(Bloomberg) –

State-controlled Brazilian oil giant Petrobras is capturing and storing a growing amount of carbon dioxide under the sea floor. This is a strategy that will help it boost oil and natural gas production. It also calls it green.

The company is pursuing the strategy on three massive offshore oil fields located 230 kilometers (143 miles) off the coast of Rio de Janeiro. There, Petrobras uses special membranes to separate CO2 from natural gas, which is a by-product of oil production. The carbon is then injected back into the reservoir.

The technique increases subsurface pressure in the reservoirs, making it easier to bring more oil to the surface and extending field life. By removing the CO2, Petrobras can also safely pipe the remaining natural gas to shore. Otherwise, there could be potential leaks, as CO2 produces carbonic acid that corrodes steel pipelines and Brazil’s offshore gas is high in pollutants.

“This is due to operational concerns. It has nothing to do with environmental awareness,” said Cleveland Jones, a consultant and researcher at the National Institute of Oil and Gas in Rio de Janeiro. “You shouldn’t take credit for that.”

But in its most recent sustainability report, Petrobras highlights how the carbon capture program reduces emissions intensity, or the amount of greenhouse gases emitted per barrel of production. Also, CO2 capture is listed as one of the greatest achievements in green technology. In the late 2000s, Petrobras developed the technology as the most viable way to transport the gas from mid-ocean to end users on land.

Carbon injection can have an overall positive impact on climate if the carbon is captured from the atmosphere or industrial sources rather than re-injecting CO2 that was originally in the ground. However, the latter is widely used throughout the oil industry to increase fossil fuel production.

Brazil’s fossil fuel operation guidelines also forced Petrobras to act: flaring or venting the CO2 captured from natural gas would violate Brazilian regulations. To get the natural gas onshore and avoid corrosion of its pipelines, Petrobras had to find a technical solution.

In response to questions, Petrobras clarified that the program for carbon re-injection – known as carbon capture, use and storage – will not be considered as part of its net emissions reduction or as a potential source of carbon offset credits. Nevertheless, the company emphasizes that it aims to re-inject a total of 80 million tons of CO2 from 2015 to 2025, which is a big step forward in its climate commitments.

“We have the largest offshore CO2 re-injection program in the world,” says its climate change report.

Petrobras has two pipelines that use carbon capture to clean up natural gas from deep-sea fields and expects to commission a third pipeline next year. This could increase supply by as much as 21 million cubic meters per day and reduce Brazil’s dependence on expensive imports of liquefied natural gas from Bolivia, which has become an unreliable supplier of the power plant’s fuel.

Petrobras produces oil that is comparatively low in carbon, both due to the amount of energy expended in producing the oil and the chemical composition of the oil itself. A single well in Brazil’s so-called pre-salt offshore region can produce more than 50,000 barrels per day produce, while in the famous Permian Basin in Texas it takes more than 5,000 wells to produce the same amount. This means that less energy and emissions are required in Brazil to produce the same amount of oil. This is partly because the company uses CO2 to increase the efficiency of its wells.

While many producers are making efforts to reduce on-site pollution, the majority of a barrel of oil’s greenhouse gas emissions come from being burned by consumers for transportation or energy.

Petrobras also says more than a decade of CO2 re-injection experience will help the company explore new ways of storing carbon, such as capturing emissions from refineries and then storing them in decommissioned oil fields, which are a potential source of carbon credits would. The oil industry has pushed carbon capture and storage projects to counteract its emissions. Occidental Petroleum Corp. captures carbon from the atmosphere and injects it into oil fields. This is part of a plan that the company will use to ultimately reduce its crude oil emissions to zero net emissions.

Other big oil companies have struggled to get carbon capture to work. Chevron’s carbon capture and storage project in Australia, Gorgon CCS, injects only a third of the carbon it’s supposed to inject and has years to work to reach full capacity. The project was intended to capture 4 million tons of CO2 annually from a liquefied natural gas plant and store it in an underwater reservoir.

According to numerous lines of research, carbon capture must increase by 2050 to reach net-zero if the world is to avoid warming more than 1.5°C. While more than $7 billion was invested in carbon capture projects between 2018 and 2021, more than 70% of all captured CO2 is used for improved oil production, BloombergNEF said in a research report last year. The report also states that the more than 30 years of use of carbon capture for oil production by fossil fuel companies has contributed to a lack of societal acceptance of the technology.

© 2023 Bloomberg LP

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