Analysis of factors influencing the efficiency of hydrochloric acid treatments

Key words: large-volume acid treatments, injection rate, reservoir coverage, estimation of incremental oil rate.

The primary method applied in Tatneft OAO to stimulate oil production from carbonate reservoirs is based on hydrochloric acid injection. Therefore, efficiency of hydrochloric acid treatments was analyzed depending on specific acid volumes and injection rates. In the course of the analysis, acid treatments were classified according to specific injection volumes, and a separate group of large-volume acid treatments was singled out. Acid penetration depth was estimated using a simple numerical model of acidizing process in carbonate reservoirs.