Waterflood monitoring with tracers

Waterflood monitoring is one of the main aspects of Enhanced Oil Recovery as it needs quality and control requirements of injecting water and accurate chemical, physical analysis of fluids. Tracers help to assess the optimum flowing path of an existing pattern. Therefore, this monitoring program follows the approaches and methods described based upon the developed design solution and experience obtained over operation time.

Injection Water Quality Requirements

The water quality required for an oil reservoir is primarily a function of reservoir permeability. Tight, low-permeability zones generally require better-quality water than higher-permeability zones.

When the injection water quality is inadequate, the consequence can be inferior a reservoir plugging. The result of plugging is reduced sweep efficiency, which results in decreased recovery and, ultimately, loss of revenue. Also, operational costs are increased because of workovers and system repairs required to restore injectivity.

Generally, the following analyses and calculations are required to determine Injection water quality:

Injection water physical and chemical characteristics;

Sulphate reducing bacteria (SRB) count;

The suspended solids content and particle size distribution;

Scaling tendencies;

Injection and formation water compatibility (total produced formation water and produced formation water from different oil wells);