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Improvements on existing wells' potential are crucial towards ensuring an economically viable project. Among various artificial lift techniques, gas lift is considered as one of the most efficient when associated gas capacity is available, and well production parameters are favorable. Also, jet pumps are specifically favorable for horizontal wells due to the relative ease in downhole installation. This paper combines these two techniques to introduce and evaluate an innovative hybrid method. It provides optimum operating windows for its design and application. This study aims to introduce and benchmark a newly proposed hybrid lift techniques for horizontal wells. Some features of this method are: 1) The operating Gas Lift Valve (GLV) is installed at the bottom of vertical. 2) The jet pump is installed below the GLV. 3) The power fluid and gas are injected through the casing-tubing annulus. 4) The pressure of gas, provided by the compressor, is used to push the power fluid through the jet pump nozzle and into the tubing. An analytical model is applied to simulate this hybrid lift technique through nodal analysis, combining models for reservoir inflow, flow through jet pump, and two-phase flow in wellbore. A sensitivity study is conducted to understand the effects of depth, API gravity, water cut, reservoir pressure, gas-liquid ratio (or gas injection rate), nozzle pressure, and nozzle and throat area ratio (R ratio) on the proposed hybrid lift's performance. A hybrid lift operating window is defined as the conditions that result in higher production rates than gas lift alone. The largest operating window is present for shallower wells with larger tubing diameters. The R ratio effects are variable throughout the cases and an optimal R ratio design is needed for each specific case. The required optimal GLR is observed to be always lower for the hybrid lift system compared to gas lift, making it relatively easier and cheaper to achieve. Overall, the operating window for application of hybrid lift is: 1) larger tubing size, 2) higher water cuts, 3) shallower wells, 4) lower required GLR's, 5) heavier oils, 6) higher nozzle pressures, 7) depleted reservoir pressures, 8) higher R ratios (if the well can handle the friction). Additional economic considerations are necessary to better evaluate this technique and determine its optimum operating window. This innovative hybrid gas lift technique can be widely applied towards increasing well's performance, life, and economic viability. It shows its true merit in seemingly less promising and difficult cases with higher water cuts and lower reservoir pressures by increasing benefit throughout the life of the well.

Aim:The foremost aim of the present study was to formulate a Diclofenac Sodium tablet of 50mg using the direct compression method with directly compressible (DC) grade excipient and the wet granulation method. Materials and Methods: Comparative study of evaluation parameters like micromeritic properties of directly compressible powder blends and granules obtained by wet granulation was carried out to analyze the suitable method for tabletting. Evaluation parameters such as tablet description, hardness, friability, drug content, disintegration time, and dissolution study were analyzed and compared for tablets manufactured by direct compression using DC grade excipients and wet granulation methods. Results: The results of all evaluation parameters were well within the limit as per Indian Pharmacopeia (IP). Edges and Surface morphology of tablets were studied using Scanning Electron Microscopy (SEM). In-process hold time for tablets was studied by performing hold time stability study. The present work was also focused on the comparison of tablets physicochemical properties manufactured from direct compression using DC grade excipient and wet granulation methods. Conclusion: The results of disintegration and dissolution studies revealed that the tablets manufactured using direct compression using DC grade excipients were completely disintegrated in a short time and steadily dissolved at a faster rate respectively compared to the tablet manufactured from wet granulation method. Hold time stability study showed that the directly compressible tablets were more stable than the tablet formulated using the wet granulation method.

Efficient processing of fluids from flowing wells is an important function on a topside facility to maintain optimum hydrocarbon production. Many oil and gas facilities face the additional challenge of limited available footprints to process additional capacity. Normally, onshore facilities move process fluids from the wellhead to a de-sander unit, and then to a 2-phase or 3-phase separator unit. In offshore and onshore production facilities, fluids from multiple wells are sometimes co-mingled in a manifold and processed through two or three separation stages with progressively lower pressures to separate gas, crude oil, and produced water. Sequential pressure letdown and numerous fluid pump-around loops to separator vessels and interconnected piping with pumps, valves, and instrumentation occupy a large space on a wellsite. To add processing flexibility in an ever-changing fluid composition (water cut, gas vapor fraction (GVF), and solids loading) from co-mingled production wells and to remove the bottleneck at the topside processing capacity, a chemically enhanced, smart compact separation system has been developed. The new separation system is based on the centrifugal (CF) separation principle. After comprehensive laboratory testing and Computational Fluid Dynamics (CFD) model validation for separated fluid streams, the system was tested in field conditions at an unconventional wellsite to benchmark mechanical reliability, separation effectiveness, and robustness. The modular design concept of this new system enables operation at 200 to 10,000 bbl/d fluid capacity at nominal increments by adding units in parallel. The system is designed to handle 30 to 99% water cut and normally encountered solids or fines concentrations. This technology is also able to handle ever-changing fluid conditions at the well such as production decline or water cut changes by using a digital interface that controls the separator operation based on inlet fluid conditions. This smart, compact separation system enables efficient separation and reduces the need for over-sized separation vessels. A 2,000 bbl/d, two-phase (oil/water) system has consistently achieved residual oil-in-water (OIW) levels below 400 ppm in the water outlet without chemical addition enhancement. The residence time for separation is less than a minute for the 2,000 bbl/d prototype unit, enabling it to be used as an alternative to a freewater knockout (FWKO) vessel. The prototype unit has a 4-in. diameter housing that is mounted on an 8-feet cast-iron frame with a 15-hp electrical motor coupled as the prime mover. The lab and long-term field test results have also indicated that the CFD simulations can effectively reveal the mechanism of oil-water separation as well as validation of separator sizing parameters for various flow capacities. The refined control algorithms are still in development phase, but when completed they will control the separator dynamically as flow conditions change in the well. A field trial to test chemical demulsifying agents will determine the final separation efficiency of this system.

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