Calcium Carbonate Scale Control in Geothermal Wells

Abstract

Scaling of wells represents a major problem to many geothermal power plants. Geothermal brines contain dissolved minerals that have a high tendency to precipitate in critical areas. In particular, formation and growth of calcium carbonate scales are harmful to operations by restricting brine flow and causing a decrease in power generating efficiency. Removal of the scale involves taking the well off line and physically cleaning the deposits downhole. This process restores the well efficiency but is extremely costly and time consuming. This paper explores the technology behind how polymeric antiscalant additives effectively and economically prevent downhole scale formation and allow for uninterrupted efficient power generation. Feeding methods, monitoring techniques and results from geothermal developers in the Imperial Valley, Coso Hot Springs, Steamboat Springs and Beowawe resources areas will also be discussed.