1 April 2019
Petrobras facing new regulations for produced water
Brazilian state oil company Petrobras is facing new regulations for its produced water discharge on offshore rigs...
Brazilian state oil company Petrobras is facing new regulations for its produced water discharge on offshore rigs. These regulations will require Petrobras to make substantial upgrades by the first quarter of 2020 to meet specs for overboard discharge and reinjection.
The new regulations are set by the Brazilian Institute of Environment and Renewable Natural Resources (Ibama) and Brazil’s National Environment Council (CONAMA). In August 2007, CONAMA Resolution 393/07 dictated that concentrations of oil and grease must be reached through gravimetric analysis. Petrobras used SM 5520 – F, which satisfied this requirement, but CONAMA’s new stance is that this method meet the parameters set forth in the new term of commitment between Ibama and Petrobras. The agreement also dictates that all discharge must be made above the surface of the sea.
The new requirements demand a different analytical method for testing produced water. Independent consultant, Dan Shannon, told Water in Oil that, “The Brazilian government is removing the silica gel step, meaning that polar hydrocarbons will be included in the discharge max metrics.” Petrobras is moving from SM 5520 - F, the silica gel wash, to SM 5520 – B, an n-hexane or other extracting solvent process. The US equivalent of this process is EPA Method 1664. The monthly and daily average limits of oil in water will remain at 29 mg/L and 42 mg/L, respectively, but Petrobras is facing significant obstacles using SM 5520 – B for concentrations of oil and grease.
A source close to the issue told Water in Oil that Petrobras’ platforms will barely be able to meet the requirement, if at all. “One of the reasons is that all of the flows are much higher, the flowback rate is much higher than what it was,” the source said. Petrobras is aiming to reinject as much produced water as possible in combination with sulfate removal units for production reasons, but Petrobras maintains strict internal limits for reinjection, which are even more stringent than the new regulations for overboarding. The source did say however that the right teams are working toward helping Petrobras meet these goals, but that space and weights of the necessary equipment are going to be a big problem for them.
There was a consensus among all parties consulted that meeting these new requirements will be a considerable undertaking for Petrobras.