Naslov
A Successful Treatment of Formation Damage Caused by High-Density Brine

Autori
Čikeš, Marin ; Vranješević, Branka ; Tomić, Mihovil ; Jamnicky, Oljeg

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
EUROPEC European Petroleum Conference, PROCEEDINGS / Achenbach, Gary D. - Richardson (TX) : Dallas (TX) : Society of Petroleum Engineers, 1988, 443-453

Skup
SPE European Petroleum Conference

Mjesto i datum
London, Ujedinjeno Kraljevstvo, 16.10.1988. - 19.10.1988

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Scale Control; Calcium Sulfate; EDTA; Gas-Condensate; Case History; Croatia

Sažetak
Well Kal-4, completed at the depth of 3455-3404 m in the Panonian basin in Croatia, was tested at a maximum flow rate of 337000 m3/d of gas, 264 m3/d of condensate and at bottom-hole flowing pressure of 175 bars. Well also produced H2S and CO2. Formation pressure was 475 bars and temperature was 182 oC. After the killing of the well with solid-free, high-density completion fluid (CaBr2 brine) and recompletion, the well was put into trial production.During the next several weeks production was declining rapidly and finally stopped due to the condensate accumulation in the production string. Well test analysis indicated severe formation damage (DR=21.4) caused by the deposition of calcium sulfate scale (CaSO4) in the perforations as well as in the formation. Remedial EDTA treatment was designed. After performing a small, two-stage treatment, damage was virtually completely removed and the well was put back into production. The paper presents reservoir description, treatment design and execution, as well as pre-treatment and post-treatment analyses of the well. Chemical aspects of calcium sulfate scale deposition and dissolution by Na4EDTA is also given.

Izvorni jezik
Engleski

Znanstvena područja
Rudarstvo, nafta i geološko inženjerstvo

POVEZANOST RADA