by Pierre Ungemach & Miklos Antics
GPC Instrumentation Process (GPC IP) scored this year a new success and milestone in smart well architecture.
On July 20, GPC IP successfully completed a new anti-corrosion, fiberglass lined, production well at the Bonneuil-sur-Marne (Paris southern outskirts) geothermal district heating (GDH) site operated by SETBO, the local, city managed, heating company.
The 2,020 m deep -38° slanted, well combines a large (20" X 13"3/8) steel cased propping column and a twin (13"3/8 X 9"5/8) fiberglass production liner assembly, the casing x liner annulus being kept free (i.e. not cemented), a design initiated in 1985 on the emblematic Melun l’Almont GDH well GMA4, completed though via a simplified architecture (single 13"3/8 casing/9"5/8 fiberglass liner) and production (self-flowing) mode (P.Ungemach - 1994. A New Geothermal Well Concept. IGA News. Quat. 20; Jan. March 1995 pp.12-13).
This former experience validated the fiberglass lining concept with respect to material aging (no fiberglass wheep nor destructuring), well integrity (no heavy duty workover and no acidizing so far), reduced maintenance (only one master valve change), well productive performance (artesian, non-sustained, 300 m3/h flowing rate under 2 bar wellhead pressure), in spite of below bubble point self-flowing production and related fluid degassing.