Smart SRUs Pre-Investment Utilizing Oxygen Enrichment Technology

2021 ◽  
Author(s):  
Waleed Alhazmi ◽  
Maher Alabdullatif

Abstract This paper presents an unparalleled engineering assessment conducted to evaluate the feasibility of pre-investing in O2 enrichment technology, with the purpose of increasing the processing capacities of conventional air-based sulfur recovery units (SRUs). Ultimately, the goal is to minimize the overall number of required SRUs for a greenfield gas plant and, consequently, capture a significant cost-avoidance opportunity. The technology review revealed that a high-level O2 enrichment can double the processing capacity of air-based SRU, depending on the H2S content in acid gas. As H2S mole fraction in feed increases, the debottlenecking capability increases. For the project under assessment, the processing capacity of air-based SRUs showed a maximum increase of 80%. On the contrary, operating with high O2 levels, will elevate SRU reaction furnace temperature, and mandates installing high-intensity burners, along with special control and ESD functions, to manage potential risk and ensure safe operation. Additionally, the liquid handling section of SRUs (condensers, collection vessels, degassing vessels, sulfur storage tanks) should be enlarged to accommodate more sulfur production. Typically, the enriched oxygen can be supplied from air separation units (ASUs), which entails significant capital cost. Apart from these special design considerations, there are several advantages for adopting this technology. Oxygen enrichment removes significant nitrogen volumes, which reduces loads on Claus, tail gas treatment, and thermal oxidizer units. Hence, lower capital cost for new plants is acquired due to equipment size reduction. In addition, higher HP steam production and less fuel gas consumption are achieved. Conventionally, O2 enrichment technology is employed in the initial design stage or used to retrofit operating SRUs facilities. However, it is unique to consider O2 enrichment-design requirements as part of new air-based SRUs design for phased program development. The objective is to enable smooth transition to fully O2 enrichment operated SRUs at a later phase of the project without the need for any design modification. This exceptional pre-investment strategy has resulted into reducing the required number of SRUs at phase II from eight to five units; and accordingly, a significant cost avoidance was captured.

2021 ◽  
Author(s):  
Prasad Kunnathully Prabhakaran ◽  
Cibu Varghese ◽  
Faris Ragheb Kamal

Abstract As part of a green field development project for ADNOC offshore, NPCC here in after called as "contractor", successfully completed installation of an oil and gas processing super complex at offshore Abu Dhabi. This super complex consisted of four large interconnected platforms of different functionalities and an accommodation platform. Associated flare structures and interconnecting bridges were also installed as part of this project. Weights of the topsides in this project were varying from 7,000MT to a ∼32,000 MT. All these topsides were installed by float-over method using contractors own cargo /launch barge fleet. Gas treatment platform topside installed as part of the above project is the world's heaviest single-module topside Installed by float-over on a fixed steel jacket. Float-over is the process of installing the topside on a preinstalled jacket by ballasting and/or by other methods of load transfer such as hydraulic jacks. This installation method is widely used for heavy topsides, due to its cost effectiveness and efficiency. By float over installation method, the topside can be installed as a single integrated unit after completion of all hookup and commissioning works onshore. This paper outlines installation engineering challenges during EPC phase for the gas treatment platform topside. Design of this topside went through phenomenal changes in terms of its size and weight during EPC phase and posed several challenges to install this unit as a single module. This paper presents the installation method, and various parameters considered during installation and also includes discussion on selection of float-over barge, importance of weight control & layout design, finalization of topside support height on barge and installation aids. This paper also presents various installation engineering analyses required during design stage. Float-over installation of the gas treatment platform was carried out by the conventional load transfer method (by ballasting) and using normal spread mooring arrangement.


Author(s):  
Aboubaker Z Masoud ◽  
Iqbal M Mujtaba

In this paper, the effect of operating decisions on the design and energy consumption for inverted batch distillation is considered. In distillation, utility cost is a function of column vapour load (V). We present a different type (as compared to what is available in the existing literature) of optimisation problem formulation and show that for a fixed market demand scenario minimisation of V for a given N will not only minimise the utility cost (cooling water + energy cost) and the capital cost but will also maximise the profitability of the operation. Also, with several examples of binary separation, it is shown that the decision of operating policy (such as constant reboil ratio, time dependent reboil ratio, etc.) at the design stage can have a significant impact on the capital and utility cost and overall profitability. This will in turn have significant effect on global warming as savings in utility cost reflects savings in energy cost. For difficult separations, which are capital and energy intensive, 40% savings in capital cost, 60% savings in utility and 70% improvement in profitability are possible if operating decisions are taken at the design stage.


2021 ◽  
Author(s):  
Oleksandr Spuskanyuk ◽  
David C Haeberle ◽  
Brandon Max Baumert ◽  
Brian Matthew King ◽  
Benjamin T Hillier

Abstract The growing number of upcoming well abandonments has become an important driver to seek efficiencies in optimizing abandonment costs while establishing long term well integrity and complying with local regulatory requirements. With an increasing global inventory of Plug and Abandonment (P&A) candidates, Exxonmobil has been driven to look for the most reliable, safe, and cost-efficient P&A technologies. ExxonMobil's P&A guidelines are consistent with and often more stringent than the local regulatory requirements but are also achievable, at least in part, with rigless technologies, leading to a more cost-efficient approach while ensuring well integrity. The objective of this paper is to demonstrate the success of rigless abandonments and their benefits compared to rig-based solutions. When developing a well abandonment plan, it is essential to consider a number of factors. These include local regulations, identification of zones to be isolated and suitable caprocks, and recognition of constraints including well history, conditions and uncertainties. Teams should begin with low cost operations without a rig if possible, estimate costs and effectiveness to achieve the barrier requirements, and evaluate batch operation opportunities for multi-well programs. ExxonMobil case studies are shown to help describe in detail how to make decisions about applicability of rigless abandonment options and how to properly execute such abandonments to achieve compliance with the barrier requirements. It has been demonstrated that significant cost savings can be achieved by staging the abandonment program in a way that lower cost technologies are utilized during the early stages of well abandonment, starting with wireline where possible, followed by coiled tubing and finally by a pulling unit, as appropriate. P&A execution could be achieved without a rig in a majority of cases, including most offshore wells, with the need to use a rig only in special circumstances or phases of execution. It is important to note that the barrier placement and safety of rigless P&A execution will not be compromised, as compared to the rig-based P&As. Additional cost savings could be achieved by further optimizing P&A design at the well design stage, ensuring that there are no built-in limiters that would prevent rigless P&A execution at the end of well life. Several case studies from ExxonMobil's global offshore experience demonstrate the feasibility and effectiveness of rigless P&A operations, with significant cost savings compared to rig-based P&As. It has been evident that rigless P&A choice is applicable to the variety of ExxonMobil's P&A projects of different complexities, with the same or superior quality of abandonment and safety record.


Author(s):  
M. R. Acton ◽  
P. J. Baldwin ◽  
R. P. Cleaver ◽  
D. J. McCollum

This paper describes a package of computer models that has been developed to assess the risks from gas releases at above ground installations associated with natural gas transmission pipelines. The package can be applied to compressor stations (containing compressor enclosures and associated gas treatment equipment) and pressure reduction stations, through to single block valve installations. It has been designed for used by safety engineers in performing quantified risk and hazard analysis, as required to meet regulatory requirements, such as the COMAH Regulations or the DSEAR Regulations in the UK. It can also be used in the design stage of projects to support decisions related to site layout for example. The package contains a range of mathematical models to assess the consequences of accidental releases of gas (including outflow, dispersion, gas accumulation, fire, explosion and thermal and overpressure response), validated by data from large and full scale experiments. The individual models are linked in a logical manner constructed around a series of “knowledge bases” that provide a defined structure to allow a wide range of different scenarios to be assessed. The predictions of the consequences arising from various scenarios can be combined with estimates of the frequency of initiating events (based on industry statistics where available, or using predictive models), in risk calculation routines which sum the outcomes for the different scenarios to calculate individual and/or societal risk. To illustrate the use of the techniques, examples of their application are given. In particular, it is shown how the risks arising from releases from high pressure vessels or in confined volumes, such as compressor enclosures, can be evaluated.


Author(s):  
Alberto F. Marti´n Ghiselli ◽  
Rau´l M. Kulichevsky ◽  
Mauricio A. Sacchi ◽  
Alberto J. Pastorini ◽  
Ce´sar G. Belinco

A flow-induced vibration problem evaluation of a shell and tube cooling water heat exchanger equipment installed in a power plant is presented in this paper. The problem produced loss of thickness in many tubes of the bundle, by impact or fretting wear, and the need to plug these tubes to avoid leakage. These vibrations could had been produced by changes in the equipment operational conditions or by a wrong evaluation during the design stage. An analytical and experimental evaluation was made to predict tubes dynamical response and to identify the excitation mechanisms. The original design modification adopted to solve the problem is presented and evaluated.


1995 ◽  
Author(s):  
Ramesh B. Poola ◽  
Henry K. Ng ◽  
Raj R. Sekar ◽  
John H. Baudino ◽  
Christopher P. Colucci

2019 ◽  
Vol 105 ◽  
pp. 02017
Author(s):  
Olesya Aksenova ◽  
Evgenia Nikolaeva ◽  
Riccardo Paulman

The article seeks to examine the efficiency of applying means of mathematical processing and computer modeling of the work processes of gas cleaning facilities of power plants to optimize the process of planning and designing of future power plant in operation. A way of solution of the gas outbursts cleaning problem at the stage of designing measures for the development of waste processing systems through mathematical processing of expected volumes of gas outbursts and computer simulation of individual pieces of equipment and working areas as a whole is offered. The authors present the results of the processing of the projected technological processes and the gas outbursts cleaning facilities in terms of E-networks and using mathematical processing in the application Simulink, which allows to build a model of the device and to carry out calculations on the screen using the library of building blocks. A 3D model of the gas cleaning facilities, which allows to visualize the technological process and to compare it with theoretical calculations at the design stage of the future power plant and, if necessary, make changes to the project, has been created by means of computer modeling.


2018 ◽  
Vol 6 (2) ◽  
pp. 197-208 ◽  
Author(s):  
Jung Min Park ◽  
Byung Chai Lee ◽  
Soo Won Chae ◽  
Ki Youn Kwon

Abstract In the computer aided engineering process with finite element analysis, a CAD surface model is sometimes needed for various tasks such as remeshing, shape optimization or design modification. Occasionally, engineers who perform an analysis at the product design stage are given only finite element mesh models; corresponding CAD models can be unavailable. This paper presents a method to extract free-form B-spline surfaces and certain feature curves from a surface mesh model. First, using the k-means clustering method, our process segments given meshes into a number of regions according to principal curvature information; then, region operations are performed. Next, each region is converted to an approximately free-form B-spline surface. In the last step, feature curves to create loft or sweep surfaces are calculated by minimizing the distance error. Some practical examples are also presented to demonstrate the effectiveness and usefulness of our method. Highlights We propose a new method of creating CAD surfaces from given finite element mesh model. Feature curves are extracted for creating sweep or loft surfaces. By using the generated surfaces based on the feature curves, the shape modification can be easily performed in the designing process.


Sign in / Sign up

Export Citation Format

Share Document