LABORATORY INVESTIGATIONS OF SILICATE MUD CONTAMINATION WITH CALCIUM
Item
Title (Dublin Core)
eng
LABORATORY INVESTIGATIONS OF SILICATE MUD CONTAMINATION WITH CALCIUM
hrv
LABORATORIJSKA ISPITIVANJA ZAGAĐENJA SILIKATNE ISPLAKE KALCIJEM
Description (Dublin Core)
eng
The silicate-based drilling fluid is a low solids KCl/polymer system with the addition of soluble sodium or potassium silicate to enhance inhibition and wellbore stability. Silicate-based drilling fluids exhibit remarkable shale and chalk stabilizing properties, resulting in gauge hole and the formation of firm cuttings when drilling reactive shales and soft chalks. Silicates protect shales by in-situ gellation when exposed to the neutral pore fluid and precipitation, which occurs on contact with divalent ions present at the surface of the shale. Also, silicates prevent the dispersion and washouts when drilling soft chalk by reacting with the Ca2+ ions present on chalk surfaces of cutting and wellbore to form a protective film. The silicate-based drilling fluid can be used during drilling hole section through shale interbeded anhydrite formations because of its superior shale stabilizing characteristics. However, drilling through the anhydrite can decrease the silicate concentration and change rheological and filtration fluid properties. So, the critical concentration of calcium ions should be investigated by lab tests. This paper details the mechanism of shale inhibition using silicate-based drilling fluid, and presents results of lab tests conducted to ascertain the effect of Ca2+ ions on silicate level in the fluid and the fluid properties.
hrv
Silikatna isplaka je KCl/polimerna isplaka s malo čvrstih čestica i s dodatkom topivog natrijevog ili kalijevog silikata radi povećanja inhibicije i stabilnosti kanala bušotine. Silikatne isplake pokazuju izvanredna svojstva u stabiliziranju šejla i krede, čime se postiže nominalan promjer kanala bušotine i stvaranje čvrstih krhotina tijekom bušenja kroz reaktivne šejlove i meke krede. Silikati štite šejlove in-situ geliranjem u kontaktu s neutralnim slojnim fluidom i taloženjem do kojeg dolazi uslijed reakcije silikata s dvovalentnim ionima prisutnim na površini šejla. Tijekom bušenja kroz meku kredu silikati sprečavaju disperziju i proširenja jer reagiraju s Ca2+ ionima koji su prisutni na površini krhotina krede i stijenki kanala bušotine i formiraju zaštitni film. Zbog njenih superiornih svojstava u stabiliziranju šejla silikatna isplaka se može koristiti tijekom bušenja kroz naslage anhidrita sa proslojcima šejla. Međutim, bušenje kroz anhidrit može dovesti do prevelike potrošnje silikata odnosno smanjenja njegove koncentracije u isplaci, te promjene reoloških i filtracijskih svojstava isplake. Zbog toga je neophodno provođenje laboratorijskih ispitivanja radi utvrđivanja kritične koncentracije iona kalcija u isplaci. U, radu se opisuje mehanizam inhibicije šejla kad se koristi silikatna isplaka, i prikazuju rezultati laboratorijskih ispitivanja provedenih radi određivanja utjecaja Ca2+ iona na razinu silikata u isplaci i na njena svojstva.
Creator (Dublin Core)
GAURINA-MEĐIMUREC, NEDILJKA
SIMON, KATARINA
MATANOVIĆ, DAVORIN
Subject (Dublin Core)
eng
drilling;wellbore instability;inhibition;contamination;silicate-based mud;lab tests
hrv
bušenje;nestabilost kanala;inhibicija;zagađenje;silikatna isplaka;laboratorijska ispitivanja
Publisher (Dublin Core)
Faculty of Mining, Geology and Petroleum Engineering University of Zagreb
Date (Dublin Core)
2004
Type (Dublin Core)
text
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://hrcak.srce.hr/13366
eng
https://hrcak.srce.hr/file/20485
Source (Dublin Core)
Rudarsko-geološko-naftni zbornik
ISSN 1849-0409 (Online)
Volume 16
Issue 1
Language (Dublin Core)
eng
Rights (Dublin Core)
info:eu-repo/semantics/openAccess
The author and publisher rights are visible during the submission process, and ethical codex is available at http://hrcak.srce.hr/ojs/index.php/rgn/about/editorialPolicies#custom-0 .
The Bulletin is open access (OA, green model, CC-BY) journal what means that electronic versions of articles are accessible to readers, without any fees or registration.When use, please refer to Creative Commons license (BY type, http://creativecommons.org/licenses/by/4.0/ ).
Publisher copyright policies & self-archiving is also described at Sherpa organisation web (RoMEO service) based at the University of Nottingham (http://www.sherpa.ac.uk/romeo/pub/2374/).
All volumes of the Bulletin (from 1989) are available at Hrčak journal pages (http://hrcak.srce.hr/rgn-zbornik?lang=en).
The Bulletin is open access (OA, green model, CC-BY) journal what means that electronic versions of articles are accessible to readers, without any fees or registration.When use, please refer to Creative Commons license (BY type, http://creativecommons.org/licenses/by/4.0/ ).
Publisher copyright policies & self-archiving is also described at Sherpa organisation web (RoMEO service) based at the University of Nottingham (http://www.sherpa.ac.uk/romeo/pub/2374/).
All volumes of the Bulletin (from 1989) are available at Hrčak journal pages (http://hrcak.srce.hr/rgn-zbornik?lang=en).