Technology Roadmap for Wastewater Reuse in Petroleum Refineries in Brazil

Because of the planned expansion of Brazil’s refining capacity called for in the government’s energy policy and the scenario of stress on water resources, it is necessary to design the country’s new refineries so as to minimize water consumption and maximize reuse of effluents. Existing refineries are large water consumers. In 2009, Brazilian refineries consumed 254,093 m3 / day of water (estimated from the water consumption index of Petrobras refineries, of 0.9 m3 water/ m3 of oil) (Amorim, 2005). Empresa de Pesquisa Energetica EPE (“Energy Research Company”), a federally owned company that is part of the Ministry of Mines and Energy, forecasts an increase of 79% in Brazilian refining capacity with the construction of new refineries by 2030 (EPE, 2007). Some of them are planned for the Northeast region, which suffers from water shortage. While Brazil as a whole is blessed with water, having roughly 13% of the planet’s freshwater reserves (Mierzwa & Hespanhol, 2005), these resources are very unevenly distributed, with some regions plagued by shortages (arid and semi-arid regions) and others blessed with abundant water. Finally, although the country’s industrial heartland, the state of Sao Paulo, and the center of its oil industry, the state of Rio de Janeiro, both are in the country’s semi-tropical region, they still face problems of water shortages due to high demand, causing conflicts among watershed users. The methods to reduce water consumption are conservation, recycling and reuse. Among the three, water conservation requires the least effort and investment costs. It involves the rational use of water by industry, incorporating measures to prevent physical losses and improve operations (Matsumura & Mierzwa, 2008). Recycling (with regeneration) refers to the use of treated wastewater at the place of origin. Finally, water reuse can occur in the following forms: a) direct reuse of wastewater in other processes, when the level of contamination does not interfere in the next process; and b) with regeneration, which is reuse of treated effluent in different processes than the original one (Wang & Smith, 1994). An important energy efficiency program was launched in 1992 by the U.S. Environmental Protection Agency, called Energy Star. As part of this program, a guide was issued focused on the refinery industry (Worrell & Galitsky, 2005). However, this document only covers energy use by refineries. There is a need for a similar document on efficient water use by refineries. Therefore, against the backdrop depicted above of unevenly distributed and locally insufficient water resources, a technology roadmap for Brazilian refineries is important.