Q&A: A defense of Brazil gas reinjection
Brazil oil and gas institute IBP's director, Sylvie D'Apote, spoke to Argus about the country's high levels of natural gas reinjections — when gas is pumped back into wells to enhance oil recovery or avoid flaring — the country's evolving gas market and onshore/offshore prospects. Edited highlights follow.
Some market participants argue the amount of gas available in Brazil's market is limited by reinjections. Could Brazilian fields focused on oil transition to gas?
Reinjection is a common misconception in this country as it is necessary for oil production in the country's pre-salt layer, in the [offshore] Santos basin, southeast Brazil. Alternating gas and water reinjections has proved to be an efficient technique to recover pre-salt oil.
But there is no reinjection of gas in other fields outside the pre-salt. Only water is reinjected in the Campos basin.
It is also true that the gas reinjected today can be produced in the future. In the pre-salt, this will take time because it is a relatively new oil and gas province, with production starting in 2011. An example of a mature field that is turning from oil to gas is the Urucu complex, in the Solimoes basin, in the Amazon region.
Urucu is one of Brazil's largest onshore gas producers, responsible for 9pc of domestic output, the same as the Campos basin and only smaller than pre-salt reservoir. Why is that?
The Urucu project started in the 1980s. For at least 20 years all gas was reinjected because there were no pipelines to take it to [Amazonas state capital] Manaus, the only city in the region. Then a pipeline was built, but demand has been lower than production, so about half of gas production continued to be reinjected. After so many years, gas production is increasing steadily while oil production is dropping.
In the last 22 years, oil output dropped by 72pc and natural gas output rose by 129pc.
That is the first such case in Brazil, but there are [similar] examples in other countries, such as Norway and Colombia.
Norway has started a blowdown process in the Oseberg field — shifting from gas reinjections to gas production. If Brazil's giant gas fields are still far from blowdown, what can shake the country's gas market?
Brazil has several mature fields in Campos, which can still produce quite a lot of oil — and less gas — with secondary and tertiary stimulation.
But it is important to remember that the basin was never a gas-prone area and that there were almost no gas reinjections [there]. By the end of the decade, three major projects — the Rota 3 pipeline, the Raia fields and the Sergipe deep waters project — will provide over 52mn m³/d of gas to the market, which will double the supply to the firm gas market in Brazil, notwithstanding demand from power plants.
Apart those projects, what can we expect for the natural gas market in Brazil?
We can expect new production from other offshore discoveries outside the pre-salt perimeter, such as the Gato do Mato discoveries in the Santos basin.
Also, there is a new trend that has been ongoing in onshore and shallow waters especially in Brazil's northeast, with new independent companies with strong recovery expertise technology for mature or marginal fields divested by Petrobras.
Some fields have now doubled or tripled production. Even if we are talking about smaller volumes, it's extremely revitalizing for local economies.
