Sand Control Technology for Extended-Reach Wells: Best Practices from the Longest Gravel Packs Performed Offshore Brazil

Abstract

The Campos basin is a sedimentary basin located in offshore Brazil, between the north coast of Rio de Janeiro State and the south coast of Espírito Santo State, encompassing many oilfields. Most of the reservoirs in the basin are high-permeability sandstones containing low API gravity oil but are without strong water drives. Long horizontal producer wells are the best economic option for field development but require water injection to maintain reservoir pressure. Horizontal sections generally range from 1000 to 2000m, which demands gravel pack as a sand control method. Gravel packing such long wells is a challenge and requires thoughtful engineering to optimize pumping techniques and technology. Presented here are best practices to overcome several challenges faced in this field to achieve overall success. The challenge for extended-reach gravel packing is that the long horizontal section develops high friction during the alpha and beta wave propagation. Increasing the pumping pressure to overcome this friction increases the risk of fracturing the formation, consequently reducing the equivalent circulation rate downhole impairing the proppant transportation. In contrast, a reduced pump rate during alpha wave propagation can lead to a premature screenout due to the increase in dune height of over 85%. To overcome these issues and place gravel packs in these wells, careful engineering and simulation, lightweight proppants, friction reducers, and thorough job planning were used to successfully perform gravel packs in more than 40 horizontal wells completed in the Campos basin from 2011 up to 2017. The experience of pumping the longest gravel pack jobs in offshore Brazil (horizontal length more than 2,000m) offer insights into best practices for gravel packs in extended-reach horizontal wells: Design considerations, specific well challenges faced, technologies deployed, and operational planning requirements. Specifically, highlighting the benefits of using lightweight proppants and optimized fluid systems to minimize screen out risks and maximize pack efficiency.

The Gravel Packing Length Determination Method and Influencing Factors Analysis in Deepwater Horizontal Wells

“…It can be seen from Figure 6 that for higher pump rate, the α-wave sand bed height can be controlled to successfully complete the α -wave packing stage. However, for β -wave 6 Geofluids packing stage, the reverse packing length of β-wave is mainly affected by the packing pressure [19,20]. With the increase of pump rate, the complete α-β wave packing length decreases.…”

Simulation and application analysis of gravel packing in deepwater HT/HP wells

“…The significant temperature change phenomenon leads to significant changes in the physical properties of carrier fluid, resulting in drastic changes in packing friction and packing pressure. So how to overcome the operation contradiction of gravel packing in deepwater horizontal wells and achieve high quality and effective packing has become a key technical problem for effective offshore oil and gas development 14–16 . According to the specific characteristics of deepwater high‐temperature and high‐pressure (HT/HP) and multichannel, a gravel packing coupling model for deepwater HT/HP horizontal well based on the α–β wave packing theory 17 is established, the influence of slurry flowing through long and multichannel and temperature alternation along flow path are considered.…”

“…So how to overcome the operation contradiction of gravel packing in deepwater horizontal wells and achieve high quality and effective packing has become a key technical problem for effective offshore oil and gas development. [14][15][16] According to the specific characteristics of deepwater high-temperature and high-pressure (HT/HP) and multichannel, a gravel packing coupling model for deepwater HT/HP horizontal well based on the α-β wave packing theory 17 is established, the influence of slurry flowing through long and multichannel and temperature alternation along flow path are considered. The packing simulation algorithm and calculation process are designed to realize the temperature-pressure simulation and multistage fine friction calculation of gravel packing in deepwater HT/HP horizontal Wells.…”