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This paper aims to describe a model created to determine various important parameters to monitor oil producer wells with different artificial lift types: Jet Pump (JP) and Electric Submersible Pump (ESP) of Mangala & Aishwarya fields. The fields contain medium gravity viscous crude (10-40cp) in high permeability (1-5 Darcy) sands. In order to overcome adverse mobility ratio and improve sweep efficiency, polymer flooding was adopted. As the Polymer flooding proceeded, polymer breakthrough in producer wells was observed. The major challenges faced in producer wells is polymer/scale depositions realized during well interventions. This issue has surfaced in field due to polymer breakthrough in oil producers and mixing of produced polymer concentration in well fluid with scales, wax or other bivalent ions. Major concerns due to polymer deposition included, fouling of artificial lift system, decrease of well uptime, jet pump (type of artificial lift) & ESP efficiency decrease. ESP & Reverse jet pumping are the major artificial lifts for the field, where power fluid is pumped through annulus and production is taken through tubing. With continued jet Pump fouling due to Polymer, wax & scale agglomerate, well uptime decreased. During jet pump redressing, polymer deposition has been observed in the body X-over (reservoir liquid path), check valve assembly, throat and spacer nozzle to throat inside jet-pump. Thus, a necessity was felt to address the issue with a proactive approach. Continuous chemical dosing method was tried and proven successfully, but it was not cost effective. Hence empirical based modelling was required which can quantify these parameters to plan for well intervention & well clean-up jobs. The developed model is "intelligent" and determines various parameters like – Productivity index(PI) of jet pump well without having suction pressure data, jet pump nozzle loss coefficient, ESP pump efficiency (ESP wear), annulus deposition & debris deposition in tubing reducing effective ID of annulus & tubing respectively. The model calculates from every newly logged Multiphase flowmeter rates, water cut, Annulus pumping pressure & tubing head pressure (THP) events and determines its approach of marking the risk levels of a well. With continued JP/ESP fouling, tubing deposition & PI drop due to Polymer, wax & scale agglomerate, well uptime & production rate is decreased.

Poor conformance & injectivity sustenance is a major concern of Mangala, Bhagyam & Aishwarya (MBA) fields. The presence of high permeability streaks or thief layers between injection and production wells typically results in pre-mature water breakthrough, high water cut and deficient volumetric sweep. As a result, significant oil volumes in the reservoir may not be contacted by the injection fluid. Another concern is of low VRR (Voidage Replacement Ratio) in some of the layers due to reduced injectivity in those sands. Consequently, it has led to poor recovery from those sands. It is also a growing problem with the polymer deposition taking place in the wellbore particularly Mangala (undergoing full-field polymer flooding), leading to challenging wellbore cleanup operations. Several methods have been used in the past, both mechanical and chemical to improve the treatment fluids during stimulation. In this paper, we introduce a novel technique; Radial Jet Drilling (RJD) for Injection & Conformance Improvement which is practical & effective and has resulted in injection improvement of greater than 100% and at-least 3x sustained treatment result over conventional techniques performed earlier. The technique involves running in hole the RJD deflector shoe on jointed pipe (typically 2-3/8") to the target depth & correlated. This is followed up with high pressure coiled tubing to rig up over the jointed pipe string and perform operations in two steps:Milling to establish Casing exitJetting to create lateral of desired length (30 to 100m) Both operations require separate runs with different downhole assemblies on coiled tubing. The setup allows the operator to jet with fluid of choice depending upon the geological & well fluid understanding. The selection of depths to create desired laterals depends upon sand thickness, formation dip, sand continuity, well deviation, cement quality & few other factors which shall be discussed in this paper. As a result of the created laterals, the injection fluid experiences low pressure drops and bypasses damaged zones/permeability barriers; which ultimately results in improved injection & conformance leading to better sweep efficiency. The other advantage of the technique is the relatively easy integration of tool with existing infrastructure i.e. small horsepower rigs. This paper will document the physics behind the technique, treatment design considerations and implementation for stimulations performed across the fields using Radial jet drilling. Particular attention is paid to multiple injector well stimulation case studies from these fields, the challenges faced, the solutions implemented, results & inferences drawn using post job surveillance. The results observed across the field w.r.t injection & its sustenance performance is consistently greater over conventional methods used earlier.

Poor conformance is a major concern of Mangala, Bhagyam & Aishwarya (MBA) fields. The presence of high permeability streaks or thief layers between injection and production wells typically results in pre-mature water breakthrough, high water cut and deficient volumetric sweep. As a result, significant oil volumes in the reservoir may not be contacted by the injection fluid. Another concern is of low VRR (Voidage Replacement Ratio) in some of the layers due to reduced injectivity in those sands. Consequently, it has led to poor recovery from those sands. It is also a growing problem with the polymer deposition taking place in the wellbore particularly Mangala (undergoing full-field polymer flooding), leading to challenging wellbore cleanup operations. Several methods have been used in the past, both mechanical and chemical to improve the treatment fluids during stimulation. In this paper, we introduce a novel placement technique for Conformance Improvement which is practical, effective and durable as well as another tool variant that helps cleanup challenging wellbore environments. Typically, prior to the tool allowing for pin-point placement, the adjustable nozzle tool is run to ensure that the perforation and wellbore is cleaned up thoroughly with help of advanced fluid dynamics. The dynamic injection modulation (hereinafter referred to as, "DIM") tool for pin-point stimulation placement improves the distribution of injected fluid in the reservoir matrix by the process of dispersion. The tool generates an energized fluid pulse that allows fluid to be diverted away from established fluid paths. The pressure pulse, as it travels dilates the pore spaces thus propagating the wave further into the reservoir. The pin-point accuracy of placements leads to treating of reservoir layers which are left untreated during conventional stimulation treatments where viscous fingering effects dominate. As a result, injection fluid would divert into uncontacted layers to improve sweep efficiency. The other advantage of the tool is the relatively easy integration of tool with existing infrastructure. The tool is easily run with coiled tubing ("CT") with only addition of an accumulator unit on surface. This paper will document the tool physics, job design and Implementation technique for stimulation using Fluid Modulation tool as well enhanced well cleanup. Particular attention is paid to multiple injector and producer well stimulation case studies from these fields, the challenges faced, the solution proposed, and finally the results obtained. The results observed across the field with respect to injection performance is consistently greater than 75% over conventional methods used earlier. Also specifically, in scenarios of difficult fill cleanups, the advanced wellbore cleanup tool variant helped in multiple polymer and sand fill environment cleanouts over various wells over conventional methods of cleanup.

This paper describes simulation solution for CT(Coil Tubing) based WBCO in flowing ESP/Jet Pump wells for scale/polymer debris deposition removal prior to any treatment in well, such as – Formation stimulation, ESP treatment, etc. It also describes prediction for requirement of Surface Well Test spread support to assist Nitrogen assisted WBCO. The paper describes new way of simulation for CT WBCO job in artificially flowing wells to predict decreased Liquid rate from reservoir, CT pressure & friction pressure losses. The modelling is done in Prosper and Cerberus, the results of which are validated with surface well test and Multiphase flow meter data recorded during the jobs. The results observed were very close to modelled with a number of advantages such as – No loss returns, higher lifting velocities, prediction of increased/decreased reservoir liquid rate affecting Motor winding temperature in ESPs, no settling of debris, post job Increased Liquid gain from well, decreased tubing friction pressure loss

Bhagyam field is a shallow onshore field in Northwest India. The field development includes 150 production wells with 40 plus injection wells. The crude is sweet & light oil (27 Deg API) with 30 % wax content and a varied viscosity from range 50-450 cP. The Wax appearance temperature is ~ 2° C lower than the reservoir temperature of 53° C which impacts the completion design and affects the flow assurance of the field. In recent times, the field production has been impacted by frequent work-overs in the field. The run life of the PCP systems, which was impacted by tubing punctures that arose from substantial rod-tubing contact loads, had reduced drastically from ~ 500 days to 259 days. The objective of this paper is first to analyze the drastic reduction in the run life of the Bhagyam PCP systems and then provide design changes which when implemented increased the run life of the PCP system. The paper describes the measures taken and the design changes made to limit the system failure due to failed tubing and increase the run life of the system back to 500 days and will allow the readers to understand, in detail, the various types of problems that were encountered in operating PCP wells, the methods that were used to analyse the PCP failures, and new completion design that help to alleviate the problems to significantly improve the Bhagyam PCP run-life.

This paper summarizes the completion designs and operational challenges of successful well completions in more than 400 wells in the Rajasthan onshore block of Northwest India. The Rajasthan onshore block has three core fields, with a total 37 oil and gas discoveries. These wells were completed in over three and a half years without compromising aspects of health, safety, or the environment. During the campaign, a commendable feat of zero HSE incidents was observed.These wells are broadly categorized as development and exploration wells and include a variety of both open- and cased-hole well completions. The completion systems are wide-ranging, varying from monobore conventional completions to open-hole, sand-control applications. The scope of work and challenging parameters include highly deviated open-hole and cased-hole sections, along with complex workovers. A wide range of products and services were designed to maximize well production. The completion design included a variety of packers, flow-control devices, intervention solutions, and other relevant completion tools.There were various operational, health, safety, environmental, logistical, and manufacturing-related challenges that were overcome to drill and complete the wells. The purpose of this paper is to provide insight into the well types, completion designs, and to discuss the associated challenges.The technology and practices established from these successful operations have become the standard operating procedures for completion jobs. This paper will take the reader through the evolution of well-completions technology, from the early days, when perceived risk was both hindered and was the spark for innovation, to the present time, when this technology is routinely used to meet production and reservoir development goals.