An integrated approach for produced water treatment and injection

During the process of the development and exploitation of oil reservoirs, a certain amount of reservoir water is produced along with hydrocarbon fluids. The volume of produced reservoir water does not remain constant over time. In the initial stages of production, relatively small amounts of water are obtained in the production. Due to a strong water drive and as time progresses the amount of produced water continuously increases. The final phase of production is often characterized by an enormous production of water, which significantly exceeds the quantity of produced oil. In highly waterflooded reservoirs, the quantity of produced water is over 90% of the total produced fluids. If well stimulations or waterflooding operations have been carried out, the properties and volume of produced water may vary even more significantly. The management of produced water is generally an expensive process, regardless of the oil price. There are usually large volumes of water to be treated, prepared and injected into the appropriate underground formations or aquifers. In this paper, the integrated approach for management of produced water will be presented, which will include constant monitoring of changes in the characteristics and volume of the produced water during the entire life cycle of the fields. Similarly, there will be a focus on the optimization of the water treatment and its disposal. Screening criteria will be presented according to the disposal formation quality and design of the water treatment system. Therefore, the decision tree will be designed according to the properties of the formation in which the treated water will be injected.