Inflow Monitoring and Analysis Using Proprietary Intelligent Chemical Tracers in the Yuri Korchagina Field

Abstract

The first installation of intelligent tracers system in extended reach horizontal well was deployed by LUKOIL-Nizhnevolzhskneft LLC in a thin oil rim reservoir with a large gas cap located in the North region of the Caspian sea. Putting in operation of the Yu. Korchagin field is challenging serious tasks during development:relative zone inflow estimation;identifying intervals of water breakthrough;long-term monitoring of oil extraction and water level;monitoring of completion equipment functionality. Traditional technologies of production logging, considering complex well trajectory, are highly risky and expensive. Fiber-optic system of monitoring of Distributed Temperature Sensors (DTS) would be an ideal instrument identifying the source of gas breakthrough, but such technology is not always feasible due to necessity of rotation of the completion during its running in extended reach horizontal well. Performance of periodic field research via cable is limited due to drilling operations on the platform. In addition to perform such survey it is required to use downhole tractors to transport logging tool. Practice of tractors usage in extended horizontal wells in the field has a negative statistics to reach the toe of the well, as for a project operator it's important to verify remote flow contribution (e.g. 7000 m) in total well flow rate. To solve the above problem a relatively new monitoring technology has been applied. At stage of equipment fabrication downhole intelligent chemical sensors were installed in sand screens. Sensors are placed in the drainage area in different intervals along the well to meet objectives by the engineers of LUKOIL Nizhnevolzhskneft LLC to provide flow profiles, identify the location of gas breakthrough and confirmation of the functional work of AICD in the course of time. After selection of surface samples of hydrocarbons at the wellhead, a laboratory analysis is conducted for chemical tracers in the sample and interpretation of tracer signals during unsteady and steady state production is performed. Some period has passed related to operation of the well after its start. The first well equipped with intelligent chemical indicators has its history of production; the well performance can be evaluated both in whole, and for each zone equipped with chemical indicators. This paper will review the experience of wireless monitoring for extend horizontal well on the shelf of the Caspian sea.

The Results of the Pilot Works on Well Completion Technologies and Continuous Monitoring on the Example of Extremely Long Horizontal Wells of the Yu. Korchagin Field in the Caspian Sea

“…Polymer rods were installed in channels bounded by ribs located between the outer diameter of the pipe and the inner diameter of the screen element (Figure 18). After the logging data during drilling was interpreted, a group of engineers from the development department identified places for installing swellable annular packers (16 intervals separated by packers), as well as eight intervals for installing intelligent tracers in the lower completion for this pilot well (Shtun, 2016).…”