New Oil Recovery Enhancement Technology

15.10.2012

New Oil Recovery Enhancement Technology

A technology of increasing crude oil recovery from reservoirs by injecting microgel polymer systems with surfactants (MGS-KPS technology) is being successfully applied at OAO TATNEFT. This engineering development of TatNIPIneft experts (part of the Company) was awarded Grand Prix of the XIX-th International Exhibition “Oil and Gas. Petrochemistry - 2012”.
 
The MGS-KPS technology is designed to regulate the process of oil displacement and increase crude oil recovery in heterogeneous and multilayered reservoirs. It can be applied both at the early stage of reservoir flooding and in long-term flooding conditions. Technological effect is achieved through reducing the permeability of water-bearing intervals and increasing the efficiency of crude oil displacement from less permeable zones of reservoirs by pumping gelling polymer compositions of various types.
 
New technology provides for application of polyacrylamide based gel-forming compositions obtained through using gel (cross-linking) inductors of two types. Depending on the geological and technical conditions of the application site, different approaches are used including the injection of mobile microgel system or sequential injection of gel-forming slug and microgel composition. The inclusion of surface-active agents (surfactants) into mobile microgel system simultaneously increases the formation coverage ratio and crude oil displacement.
 
The MGS-KPS technology can be implemented in all seasons, which is provided by the lack of restrictions on the mineralization of water used to obtain compositions, as well as by the use of surfactants with a low pour point. Compared with other polymer solutions, the MGS-CPS compositions are characterized by low polymer and cross linking agent content while providing for a high residual resistance factor. This helps to reduce treatment costs without loss of process efficiency. The possibility of choosing from a variety of compositions and injection methods (depending on the conditions of a wellsite) also contributes to economic and technological efficiency.
 
New technology has been introduced at the oilfields of OAO TATNEFT since January 2012. Injection under the MGS-KPS technology has been performed in 87 injection wells during eight months of 2012. It is now very popular among all the NGDUs of OAO TATNEFT. The forecast duration of technological efficiency is 2 years.