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Roundtable

The Future of Cantarell

Wed, 01/25/2012 - 10:13

When asked about the future of Cantarell, Carlos Morales Gil, Director General of Pemex Exploration and Production, says that the company still sees Cantarell as a significant reserve base: “We have so far recovered 42% of the original oil in place at Cantarell, and the projections we have allow us to establish that we are going to recover more than 50% before the field is abandoned. This means that there is still around 10%, or around 3.5 billion bbl of oil, that we will produce in the next 20 years or so.”

Morales Gil explains the history behind the exploitation of Cantarell in detail, showing at the same time the importance that Pemex still places on the social aspect of its mandate as a national oil company. “In human terms, the super giant field contributed enormously to the public finances of the country for many years, and is still an important contributor today. Since the reservoir was first developed, Pemex managed it very well. The first wells that were drilled were very shallow, and it was not long before the company realized that these wells were not going to last, and would soon start to produce only gas. As a result of this, we started to drill to greater depths. Based on the data we gathered at the beginning of the 1980s, we soon started to understand that these deeper wells would enable Cantarell to produce upwards of 1 million bbl/day.”

It was around this time that the decision was taken to exploit Cantarell with a focus on maximizing the value that could be obtained from the field. Over the following years, new facilities were built, additional wells were drilled, nitrogen was injected, and Cantarell eventually peaked at 2.21 million bbl/day in 2003. In other fields, such as Abkatún, Pol, and Ku-Maloob-Zaap, Pemex took a different approach, extracting the reserves in such a way that a production plateau would be maintained for as long as possible. “Neither decision was incorrect; they were just taken at times when Pemex had different priorities,” explains Morales Gil.

Detailing the strategy for Cantarell in 2011, Morales Gil explains that Pemex focused on stopping the production decline and returning Cantarell to production growth through a combination of new wells, the application of new technology, and changing wells from gas lift to electric submergible pumps (ESPs). The company also looked at managing water and gas production at its declining wells. Morales Gil says that the major challenge throughout 2011 was the shortage of jack-up rigs, and that this is something that Pemex will address in 2012. “During 2011, we had to void several tenders for jack-ups due to a lack of offers. Today, this lack of jack-up rigs affects not only the Cantarell project but also other shallow water fields in the Mexican gulf. This is something that we are currently addressing, and in the mid-term at Cantarell we expect to see a slight increase in production, once we get the facilities for water and gas handling in place, and contract all the rigs we need to fulfil our drilling plans,” he says. After producing 449,000 bbl/day in 2011, this year’s production target for Cantarell will be around 480,000 bbl/day, Morales Gil says.

Carlos Morales Gil

Carlos Morales Gil

Director General
Pemex Exploration and Production

When asked about the future of Cantarell, Carlos Morales Gil, Director General of Pemex Exploration and Production, says that the company still sees Cantarell as a significant reserve base: “We have so far recovered 42% of the original oil in place at Cantarell, and the projections we have allow us to establish that we are going to recover more than 50% before the field is abandoned. This means that there is still around 10%, or around 3.5 billion bbl of oil, that we will produce in the next 20 years or so.”

Morales Gil explains the history behind the exploitation of Cantarell in detail, showing at the same time the importance that Pemex still places on the social aspect of its mandate as a national oil company. “In human terms, the super giant field contributed enormously to the public finances of the country for many years, and is still an important contributor today. Since the reservoir was first developed, Pemex managed it very well. The first wells that were drilled were very shallow, and it was not long before the company realized that these wells were not going to last, and would soon start to produce only gas. As a result of this, we started to drill to greater depths. Based on the data we gathered at the beginning of the 1980s, we soon started to understand that these deeper wells would enable Cantarell to produce upwards of 1 million bbl/day.”

It was around this time that the decision was taken to exploit Cantarell with a focus on maximizing the value that could be obtained from the field. Over the following years, new facilities were built, additional wells were drilled, nitrogen was injected, and Cantarell eventually peaked at 2.21 million bbl/day in 2003. In other fields, such as Abkatún, Pol, and Ku-Maloob-Zaap, Pemex took a different approach, extracting the reserves in such a way that a production plateau would be maintained for as long as possible. “Neither decision was incorrect; they were just taken at times when Pemex had different priorities,” explains Morales Gil.

Detailing the strategy for Cantarell in 2011, Morales Gil explains that Pemex focused on stopping the production decline and returning Cantarell to production growth through a combination of new wells, the application of new technology, and changing wells from gas lift to electric submergible pumps (ESPs). The company also looked at managing water and gas production at its declining wells. Morales Gil says that the major challenge throughout 2011 was the shortage of jack-up rigs, and that this is something that Pemex will address in 2012. “During 2011, we had to void several tenders for jack-ups due to a lack of offers. Today, this lack of jack-up rigs affects not only the Cantarell project but also other shallow water fields in the Mexican gulf. This is something that we are currently addressing, and in the mid-term at Cantarell we expect to see a slight increase in production, once we get the facilities for water and gas handling in place, and contract all the rigs we need to fulfil our drilling plans,” he says. After producing 449,000 bbl/day in 2011, this year’s production target for Cantarell will be around 480,000 bbl/day, Morales Gil says.

Gustavo Hernández García

Gustavo Hernández García

Subdirector for Planning and Evaluation
Pemex E&P

“In recent years, Cantarell’s production has been declining. At times, it appeared as if Pemex would be unable to do anything to halt this decline, but today we are proud to say that we have engineered a solution to slow this decline to the extent that we can once again rely on Cantarell to be a stable contributor to Mexico’s oil production.

“We have now reduced the decline at Cantarell to almost zero. One of the reasons that we were not able to address this decline adequately until now has been the fact that we were unable to drill the wells that were required at the field. In 2011, Pemex was unable to contract 16 of the jack-ups that it needed to drill the wells that were scheduled. As a result, we were unable to meet the original production target for the year at Cantarell. In turn, this was the underlying reason of the 1% decline in Mexico’s oil production last year.

“We are now in the process of scouring the globe for jack-ups to drill in Cantarell, and we have already found some to meet drilling demand for 2012 – recently we presented two jack-ups that we would like to contract to the board for their authorization. We expect to have additional jack-ups by the end of the year, which will help us get closer to our production targets at Cantarell through the drilling of additional wells, specifically in locations that have not yet been fully exploited by existing wells. By replacing production from workover activities, we expect to maintain a production plateau at Cantarell for the next few years of between 400,000 bbl/day and 500,000 bbl/day.”

 Javier Estrada Estrada

Javier Estrada Estrada

Commissioner
CNH

The CNH is currently producing its technical assessment of the Cantarell field, which will be released during the first quarter of 2012, but Javier Estrada Estrada explains his concerns regarding the future of Cantarell: “The pressure level of Akal, Cantarell’s main field, hasn’t achieved a steady state. Pressure is still coming down and so is production, while the gas/oil ratio is still rising. Akal’s average production rate declined from 370,000 bbl/day in 2010 to 314,000 bbl/day in 2011 according to CNH statistics, and continued to decline in the beginning of 2012.

“On a positive note, the CNH is glad to see that Pemex is complying with gas flaring, and investing more in this area. We imposed an investment plan for reducing gas flaring, which requested Pemex to invest more in gas reinjection, but we have to recognize that the field has not achieved stabilization. Pemex has managed overall to stabilize more or less the production in the whole country, but as a consequence of increasing production at KMZ and other fields rather than because of stabilizing Akal.

“In the first quarter of 2012 the technical assessment from Cantarell will be released by the CNH. I have not yet seen a draft of the report from my technical team, but I expect it will contain a recommendation to accelerate the substitution of wells: to increase the speed at which Pemex closes wells with high gas/oil ratios, and drills new wells. I expect the report will also contain some technical elements to give a recommendation of how fast you should replace wells. Together with some projects related to enhanced oil recovery.”

Grupo Diavaz

Horacio Méndez Villalobos

General Manager
Weatherford

“Weatherford is aware that Cantarell continues to be one of the main producing reservoirs in Mexico. Geologically, it is a naturally fractured anticline structure in a phase of mechanical and energy declination. To solve or improve Cantarell’s problems, the entire production system has to be analysed, from the reserve itself to the superficial installations, in order to find the best technologies that contribute effective solutions,” says Horacio Méndez Villalobos, Country Manager of Weatherford Mexico.

Méndez Villalobos believes that the field requires the implementation of an integrated productivity engineering concept, with the help of technology focused on increasing Cantarell’s recovery factor, whilst maintaining the integrity of the complex’s reserves. “Specifically, this means reducing the conification or canalization impact of the active aquifer and the expansion of the gas cap with smart and automated technologies capable of generating a self-response in terms of present fluids in the reserve and improving the availability and efficiency of the recollection, separation, treatment and distribution processes of the fluids, which is affecting the field’s productivity,” says Méndez Villalobos.

Luís Vázquez Sentíes

President
Grupo Diavaz

When asked about the importance of the Cantarell field for Grupo Diavaz, Luís Vázquez Sentíes explains that the company first started working on Pemex’s Cantarell project back in 1979. “Cantarell has been a very good project for Diavaz, we constructed pipelines, and were responsible for much of Pemex’s maintenance and construction.” Although he believes that Cantarell led to the complacency that Pemex has often been accused of in terms of replacing its reserves, Vázquez Sentíes says that the service industry cannot be accused of the same: “We had to constantly innovate throughout the field’s development in order to keep up production levels. We did a lot for Cantarell and we are still playing that role today, trying to find new ways to produce oil.” One of the secondary recovery

techniques that Grupo Diavaz has been working on is the separation of associated gas from oil produced at onshore fileds, which is then reinjected into the casing of the well rather than the reservoir, in order to increase production. Diavaz is currently in discussions with Pemex to trial this patented technology at Cantarell. Onshore, production has been increased by 30% at some wells following the application of this technology.