Using an Adjustable Cone Meter to Measure Wet Gas

A traditional fixed size Venturi meter has a turndown of about 8:1 under dry gas conditions that may drop to as low as 3:1 under wet-gas flow. When the well conditions change, a replacement of the original Venturi meter with one of a different size is needed. In this paper, we present the design, development and testing of an Adjustable cone meter that has the ability to adapt itself to the flow conditions automatically and provide a turndown of as much as a 54:1 under dry gas conditions and as much as 20:1 under wet-gas conditions. The patented feature of the Adjustable cone meter is the adjustable sleeve that moves over the cone when the flow rate decreases below a preset value causing an increase in the differential pressure across the meter. In addition, traditional Venturi meters have only one differential pressure measurement and the sensor tends to overestimate the flow when there is liquid present in the flow (wet-gas). The Adjustable cone meter has two differential pressure sensors and the second measurement is used to estimate the liquid content in wet-gas. Two meters were manufactured and tested at the National Engineering Laboratory in East Kilbride, Scotland under gas flow rates of up to 18 MMscfd. Based on the differential pressure measurements under varying flow conditions, algorithms were developed to measure the dry gas and liquid fraction. An over-reading model of the meter and a liquid fraction estimation model based on the pressure loss ratio was derived from an additional differential pressure measurement. The model was used to not only to quantify the gas and liquid flow rates but also the estimated error in each measurement. The measurements show that the Adjustable Cone meter is able to provide low uncertainty in both dry and wet gas conditions and met the conditions outlined in ISO 5167-5. The Adjustable cone meter is a much needed innovation in the area of differential pressure measurement.

INFLUENCE OF STORAGE TIMES OF SLUDGE FROM THE FERROALLOY INDUSTRY ON THE PROPERTIES OF CEMENT-BASED MIXTURES

Purpose. The transition to environmentally friendly, waste-free technologies is a priority for most countries in the world. The metallurgical and construction industries make a significant contribution to the formation of large volumes of man-made waste. During the production of ferroalloys, waste is generated in the form of sludge, which is stored in sludge collectors. Sludge storage has been going on for over 25 years. In order to study the effect of the duration of storage of sludge on its properties in the compositions of dry building mixtures on a cement basis, a comparison was made of the efficiency of using sludge with different storage periods. The influence of sludge of various storage periods on the strength of dry construction is estimated. Methodology. The studies were carried out in accordance with the standard methods for determining the physical and mechanical properties of solutions from dry mixtures for the installation of self-leveling floors, specified in DSTU B V. 2.7-126: 2011 “Sludge awesome dry modified. General technical minds”. Sludge from wet gas cleaning of ferrosilicon production is stored in dumps where it is a mixture of lumps of various fractions 5…50 mm in size. To use sludge in the composition of dry building mixtures, it must be dried and crushed on a roller crusher and on a disintegrator. Findings. The best ratio of the "age" of the sludge and its percentage in the composition of the mixture was determined to increase the strength characteristics of the cement stone. Originality. The influence of the chemical nature of sludge from wet gas purifiers of ferrosilicon production on the hydration processes and strength of cement stone is analyzed. Practical value. The use of man-made waste in the formulations of dry building mixtures helps to simultaneously reduce the harmful effect on the environment of industrial enterprises and increase the mechanical and economic characteristics of cement mortars based on dry mixtures.

Managing the Salvage, Removal, Preservation and Re-Installation of Tilted Wellhead Platform

This paper describes the planning, offshore execution and technology involved in the intact salvage, removal, preservation and relocation of a Wellhead Drilling Platform (WHP) which was tilted during drilling operation in the "X" field. The field development plan consists of a WHP tied-back to a Floating, Production, Storage & Offloading (FPSO), anchored at 700 m away from the WHP. The oil field is located 110 km from shore and at water depth of 57 m. The Project Management Team (PMT) had completed the installation of the WHP, unfortunately mishap was happened when the WHP experienced tilting during drilling operation. The platform tilted/leaned two (2) degrees towards the drilling rig. The strategy adopted by the PMT was to rig-down and move out the affected rig; immediately salvage the newly installed 1,300MT WHP's topside. The work was executed under the crisis management envelop with the aim to save the rig and platform from total loss i.e., to avoid the platform topples into the sea and subsequently hits the rig. The salvage operation employed unique processes, procedures, and technology to safe hold the tilted platform by Anchor Handling Tugs (AHTs) and pipelay barge; rig-down and move out the drilling rig, reinstatement of lifting lug/pad eyes which had previously removed after completion of topside installation and finally removal of topside from the tilted jacket. The topside then transported to the fabrication yard, where there the topside had been preserved on the transportation barge for a period of five (5) months while waiting for the new jacket to be fabricated and installed. The re-development of the affected offshore facilities from the incident involved installation of new jacket at 150 m away from the tilted jacket location, re-installation of the topside to the new installed four (4) legged jacket, re-routing the previous installed infield pipelines (8" Liquid, 16" Wet Gas and 12’ Export Gas pipeline from FPSO) and tied-in to the new platform. The planning, innovation and execution has resulted in a significant cost containment and managed to avoid major disaster; subsequently safeguard Company's reputation. The salvage of the topside and rejuvenation of the pipelines have managed to avoid the reconstruction of the topside module which potentially could lead to non-cost recovery of huge amount of additional cost (in USD millions) and managed to avoid any Loss of Primary Containment (LOPC) by taken all the necessary precautions.

A Review on the Application of Multiphase Twin Screw Pump as a Downhole Wet Gas Compressor to Improve Gas Wells Recovery Factor

By introducing a multiphase twin screw pump as an artificial lifting device inside the well tubing (downhole) for wet gas compression application; i.e. gas volume fraction (GVF) higher than 95%, the unproductive or commercially unattractive gas wells can be revived and made commercially productive once again. Above strategy provides energy industry with an invaluable option to significantly reduce greenhouse gas emissions by reviving gas production from already existing infrastructure thereby reducing new exploratory and development efforts. At the same time above strategy enables energy industry to meet society’s demand for affordable energy throughout the critical energy transition from predominantly fossil fuels based resources to hybrid energy system of renewables and gas. This paper summarizes the research activities related to the applications involving multiphase twin screw pump for gas volume fraction (GVF) higher than 95% and outlines the opportunity that this new frontier of multiphase fluid research provides. By developing an understanding and quantifying the factors that influence volumetric efficiency of the multiphase twin screw pump, the novel concept of productivity improvement by a downhole wet gas compression using above technology can be made practicable and commercially more attractive than other production improvement strategies available today. Review and evaluation of the results of mathematical and experimental models for multiphase twin screw pump for applications with GVF of more than 95% has provided valuable insights in to multiphase physics in the gap leakage domains of pump and this increases confidence that novel theoretical concept of downhole wet gas compression using multiphase twin screw pump that is described in this paper, is practically achievable through further research and improvements.