Page 231 - Geothermal Energy Systems Exploration, Development, and Utilization

4.9 Sustainability of Treatment 207

Table 4.5 Results of chemical treatments for scaling removal
and connectivity development in selected geothermal fields.

Geothermal field Methods used Number of Variation of the Improvement References
treated wells injectivity index factor
before and after
acid treatment
−1
−1
(kg s bar )
Bacman (Philippines) HCl–HF 2 0.68–3.01 4.4 Buning et al.
0.99–1.40 1.4 (1995)
Leyte (Philippines) HCl–HF 3 3.01–5.84 1.9 Malate et al. (1997)
0.68–1.77 2.6 and Yglopaz et al.
1.52–10.80 7.1 (1998)
Tiwi (Philippines) HCl–HF 1 2.52–11.34 2.6 Buning et al. (1995)
Mindanao (Philippines) HCl–HF 1 Successful 2.8 Buning et al. (1997)
Salak (Indonesia) HCl–HF 1 4.70–12.10 2.6 Pasikki and Gilmore
(2006)
Berlin (El Salvador) HCl–HF 5 1.60–7.60 4.8 Barrios et al. (2002)
1.40–8.60 6.1
0.20–1.98 9.9
0.90–3.40 3.8
1.65–4.67 2.8

Las Tres Virgenes 10% HCl–5% HF2 0.8–2.0 2.5 Jaimes-
(Mexico) 1.2–3.7 3.1 Maldonado and
S´ anchez-Velasco
(2003)
Los Azufres (Mexico) HCl–HF 1 3.3–9.1 2.8 Flores Barajas, and
Rodriguez (2006)
Beowawe (USA) 12% HCl–3% HF1 Successful 2.2 Epperson (1983)
The Geysers (USA) 5% HCl–10% HF1 No effect – Entingh (1999)
Coso (USA) HCl and NTA 30 24 Wells – Evanoff Yeager, and
successful Spielman (1995)
and Rose et al.
(2007)
Larderello (Italy) HCl–HF 5 11–54 4.9 Capetti (2006)
4–25 6.3
1.5–18 12
Successful 4
11–54 4.9