Sodium orthosilicate: An effective additive for alkaline steamflood

Steamflood performance often suffers from channelling and gravity segregation, resulting in poor sweep efficiency. Alkaline additives may be used with steam for certain types of crude oils to improve steamflood performance. In this paper, an experimental study is presented to evaluate the effectiveness of sodium hydroxide, sodium metasilicate and sodium orthosilicate for improving steamflood performance in the Wilmington Tar Zone crude oil. The experimental apparatus was designed to completely eliminate heat loss from the core so that the effects of the alkaline additives on saturated steam, rather than on the condensed water, could be studied. The results show that sodium orthosilicate outperforms sodium hydroxide and sodium metasilicate in enhancing oil recovery by a steamflood.