Original scientific paper
Laboratory evaluation of calcium carbonate particle size selection for drill-in fluids
Nediljka Gaurina-Međimurec
Abstract
The technological development in horizontal, re-entry and multilateral wells require drilling and completion the reservoir sections of a well including as little damage as possible. The trends towards open hole completion places additional emphasis on formation damage avoidance. One of critical factors in avoiding formation damage during drilling is obtaining surface bridging on the formation face with minimum indepth solids penetration. In case of overbalanced drilling, this can be donme by optimizing the particle size distribution of calcium carbonate used as bridging agent. The paper presents laboratory data frpm tests carried out on selected fluids which show the extent of the changes that occur in fluid filtration properties (spurt loss, PPT value and static filtration) when calcium carbonate with different PDS is used. The Permeability Plugging Tester was used to evaluate the filtration and spurt loss of selected fluids. The ceramic disks with permeabilities 0,09 μm2 (90 mD), 0,13 μm2 (130 mD) and 0,4 μm2 (400 mD) were used as filter medium.
Keywords
fluids; formation damage; bridging particle; particle size distribution; filtration
Hrčak ID:
5019
URI
Publication date:
4.12.2002.
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