Urucu-Coari-Manaus gas pipeline goes on stream

Natural gas will substitute for diesel fuel and fuel oil, particularly in power generation, reducing greenhouse effect gas emissions.

The Urucu-Coari-Manaus gas pipeline was inaugurated this Thursday (11/27) during a ceremony attended by president Luiz Inácio Lula da Silva. The event was held at the Isaac Sabbá Refinery (Reman), the first unit to receive the gas coming from Urucu.

 

According to Petrobras’ CEO José Sergio Gabrielli de Azevedo, the gas pipeline is ready to operate, and its usage will grow as scheduled. "All gas pipelines initially go on stream below their full capacity. The grow in time, as new demand is added on. In the particular case of the thermal demand of Manaus, the engine substitution process will follow a certain sequence until September. Therefore, the usage is entirely within the estimations of what would be normal for a gas pipeline of this type," he said.

President Lula mentioned the technical hurdles that had to be overcome for the construction and highlighted the project’s environmental benefits. "We will have a small revolution in the energy matrix in Northeastern Brazil, particularly in Manaus," he emphasized. Substituting the fuel oil the seven thermoelectric plants that supply the region with power run on for natural gas will prevent the emissions of 1.2 million tons of CO2 per year.

The contractual term for the thermoelectric plants to adapt to use natural gas expires next September. Lula and Gabrielli emphasized the need for responsibility when replacing the plants’ engines in order to avoid hindering the population’s power supply.

"We are waiting for the thermoelectric plants to complete the engine substitution process. This cannot be done all at once, as it might threaten the Manaus power system. We cannot take this chance," pondered Gabrielli.

Chief of Staff Dilma Rousseff mentioned Petrobras’ concern with the impacts of the construction. To her, the gas pipeline proves sustainable development is possible. "We were able to build the gas pipeline with full respect for the environment," she said.

Part of the Growth Acceleration Program (GAP), the gas pipeline is 661 km long on its trunk line, which connects Urucu to Manaus, and has seven branches that will be used to supply the cities of Coari, Codajás, Anori, Anamã, Caapiranga, Manacapuru, and Iranduba and range for 140 km.

The gas pipeline is a means through which a significant change will be made to the State’s energy matrix, as it will allow for the substitution of diesel fuel and fuel oil for natural gas, particularly to generate electricity.

The Tambaqui thermoelectric plant (60 MW), in which Petrobras holds 30% equity stakes, will be the first one to use natural gas to generate power in Manaus. Operation there are slated to go on stream as early as next December 21st. One of the TEP’s five engines, with 17 MW of installed capacity and with a consumption of 108,000 cubic meters per day, has been in the process of being converted to run on natural gas since August.

In addition to Tambaqui, the Manauara (60 MW), Jaraqui (60 MW), Aparecida (152 MW), Mauá (268 MW), Cristiano Rocha (65 MW), and Ponta Negra (60 MW) plants will also run on natural gas instead of on diesel fuel and fuel oil. Responsible for supplying the capital city of the state of Amazônia, together they have 725 MW of installed capacity. The use of natural gas to generate electricity in Manaus will prevent the emissions of nearly 1.2 million tons of CO2 to the atmosphere per year.

The thermoelectric plants that supply Manaus consume 1.2 billion liters of fuel oil and diesel fuel per year, according to Eletrobrás’ Annual Fuel Plan report. In order to have an idea of what this total represents, according to the NPA (National Petroleum Agency), the consumption of diesel fuel (740.4 million liters/year) and fuel oil (911 millions liters/year) in the state, for all uses (thermal and non-thermal), topped-out at approximately 1.6 billion liters in 2008.

To maintain power supply in Manaus, the plants are being converted to run on natural gas gradually. The process is expected to be completed in September 2010. Since the plants are composed of an assembly of engines, the conversion is being done machine by machine, until the entire generation park will be able to operate on natural gas.

Brazil’s second biggest natural gas reserve

The gas pipeline’s initial transportation capacity is 4.1 million cubic meters of gas per day. With the installation of two intermediary compression stations between Urucu and Coari, this capacity will rise to 5.5 million cubic meters per day, the total contracted capacity, in September 2010.

Of the 5.5 million cubic meters per day of natural gas, the volume to be used to supply the thermal market is 5.0 million cubic meters per day, while 0.5 million cubic meters of gas per day will go to fuel to the non-thermal (industrial, commercial, residential, and vehicular) market. Cigás (Companhia Distribuidora do Amazonas), the state’s utility, will be in charge of distributing the natural gas to the final consumers.

The Urucu-Coari-Manaus gas pipeline allows the natural gas produced in the Solimões Basin - Brazil’s second biggest reserve, estimated at 52.8 billion cubic meters, second only to Rio de Janeiro (144.8 billion cubic meters) - to be made available to the market. Until now, production had been reinjected on account of a lack of transportation infrastructure.

Transpetro will operate the gas pipeline. To face the unique conditions in the Amazon, a team of operators was trained for two years to do the work. As the other gas pipelines under Transpetro’s operating responsibility, the Urucu-Coari-Manaus gas pipeline will be operated in a remote, automated manner by means of the National Operational Control Center (CNCO), headquartered in Rio de Janeiro.

Technological innovations

In addition to its energetic and environmental importance, Urucu-Coari-Manaus also stands out for the unprecedented engineering solutions used during the construction that allowed the work to be completed in the shortest possible term with respect for the environment.

The gas pipeline cuts through the Amazon forest, a region marked by intense rainfall; by major variations in the levels of the water bodies (the so-called igarapés) and rivers year-round, which may swell up to 14 meters; and by soil conditions that are little favorable for machine transportation and for worker access to job sites.

To overcome these difficulties that are specific to the Amazon region and never before faced in pipeline construction, Petrobras adopted unprecedented constructive solutions as of April 2008. These innovations were deployed particularly in the 196-km section between the cities of Coari and Anamã, considered as the most difficult of the entire gas pipeline as it has the longest course of flood areas.

An onshore gas pipeline was built partially under the rivers for the first time ever, using a methodology similar to that used to build maritime ones. The solution allowed for work to continue even in the rainy season, between November and June, in hard-to-access areas.

In flooded sections, barges were turned into floating construction sites, where pipes were welded and formed columns measuring a thousand meters each. Attached to floats and barrels, the columns were transported by tow boats to other barges, where they were coupled to another column of the pipe that had already been set into its position. The ties would then be undone, one by one, in order to lower the pipes onto the ranges that had previously been cleared in the flooded areas. At least 6,000 floats and barrels were used in the operation.

In the 75-km section between Coari and Anamã, the pipes were transported by freight helicopters capable of supporting 4.5 tons each. The pipes were carried tied to 80-meter long wire ropes to the areas where access was unavailable on land, on rivers or riverbanks. The solution reduced the suppression of forest vegetation to transport the pipes to the construction sites.

To reduce employee transportation time and shorten the distances to the job sites, 22 forest camps were installed, each capable of lodging 160 people, in accordance with the models adopted by the Army for survival in the forest.

In addition to these innovations, Petrobras also deployed additional measures to preserve the region’s rivers and riverbanks. Along the 661 km of the gas pipeline’s trunk line, 19 directional holes were made, special features where the gas pipeline is buried under the river bed. The longest and deepest was the one made under the Solimões River. It is 1,821.72 meters long and runs at a depth of 102 meters.

The Urucu-Coari-Manaus gas pipeline was the pipeline construction job that used the highest percentage of local labor: 70%. About 8,900 employees worked directly in the construction, while 26,700 additional indirect jobs were created by the project. Of the workers involved in the project, 8.7% were women (774). Of all of the material used in the construction work, 95% were made in Brazil. The percentage of machines and equipment, meanwhile, was 85%.

Construction sections:

Section A (Urucu-Coari, 279 km) – This section has had a gas pipeline measuring 18 inches in diameter since 1999, which was adapted to transport liquefied petroleum gas (LPG). A new 10-inch pipeline was built in this section to transport LPG. Then, the existing gas pipeline, which until then transported LPG, was adapted to transport natural gas. The LPG pipeline went on stream last February.

Section B1 (Coari-Anamã, 196 km) – In this section, the gas pipeline is 20 inches in diameter. A part of it is in a floodable area that is difficult to access. New constructive approaches were used to do the work in this section.

Section B2 (Anamã-Manaus, 186 km) – Continuation of section B1. This section concentrates the biggest number of communities (135 in total) and 46 km of roads surrounding the gas pipeline range. Equipment and pipes were transported on barges in a few places in this area.