Aerated drilling cutting transport analysis in geothermal well

6th ITB International Geothermal Workshop

Wakhyudin, Aris^1 ; Setiawan, Deni^2 ; Marjuan, Oscar Dwi^1

Bandung Institute of Technology, Bandung, Indonesia^1

PT. Mitra Konsultansi Indonesia, Tangerang Selatan, Indonesia^2

关键词: Aerated drilling fluids;    Drilling fluid density;    Formation temperature;    Lost-circulation problems;    Non-productive time;    Oil and gas formation;    Rate of penetration;    Temperature and pressures;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/103/1/012008/pdf
DOI  :  10.1088/1755-1315/103/1/012008

来源: IOP

【 摘 要 】

Aeratad drilling widely used for geothermal drilling especially when drilled into predicted production zone. Aerated drilling give better performance on preventing lost circulation problem, improving rate of penetration, and avoiding drilling fluid invasion to productive zone. While well is drilled, cutting is produced and should be carried to surface by drilling fluid. Hole problem, especially pipe sticking will occur while the cutting is not lifted properly to surface. The problem will effect on drilling schedule; non-productive time finally result more cost to be spent. Geothermal formation has different characteristic comparing oil and gas formation. Geothermal mainly has igneous rock while oil and gas mostly sedimentary rock. In same depth, formation pressure in geothermal well commonly lower than oil and gas well while formation temperature geothermal well is higher. While aerated drilling is applied in geothermal well, Igneous rock density has higher density than sedimentary rock and aerated drilling fluid is lighter than water based mud hence minimum velocity requirement to transport cutting is larger than in oil/gas well drilling. Temperature and pressure also has impact on drilling fluid (aerated) density. High temperature in geothermal well decrease drilling fluid density hence the effect of pressure and temperature also considered. In this paper, Aerated drilling cutting transport performance on geothermal well will be analysed due to different rock and drilling fluid density. Additionally, temperature and pressure effect on drilling fluid density also presented to merge.