Experience with Chemical Injection and Umbilicals in Pre-Salt Fields

2021 ◽  
Author(s):  
Sidnei Guerreiro Da Silva ◽  
Andre Athayde Gonçalves ◽  
William Albuquerque Da Silva ◽  
Rafael Di Lorenzo Filho
Keyword(s):  
Control Systems ◽  
Deep Water ◽  
Production Systems ◽  
Poor Performance ◽  
Lessons Learned ◽  
Operational Experience ◽  
The Poor ◽  
Design Requirements ◽  
Chemical Products ◽  
Wax Deposits

Abstract The characteristics of Pre-Salt carbonate reservoirs demand downhole chemical injection to prevent scale, asphaltene, and wax deposits, besides the need of H2S scavenger, and MEG, normally injected at Xmas tree (WCT). The poor performance of injection systems installed in Santos Basin, together with production risks associated to the lack of chemical injection, led the project team to re-evaluate design requirements, such as chemical products characteristics, production systems equipments, umbilicals, and chemical injection valves. In addition, umbilical failures are being observed in other deep-water fields, related to subsea control systems functions. This paper focuses on Company operational experience and lessons learned related to umbilicals and downhole chemical injection.

scholarly journals Communication of Intent in Distributed Supervisory Control Systems

1997 ◽  
Vol 41 (1) ◽  
pp. 259-263 ◽  
Author(s):  
Lawrence G. Shattuck ◽  
David D. Woods
Keyword(s):  
Control Systems ◽  
Dynamic Process ◽  
Supervisory Control ◽  
Poor Performance ◽  
Us Army ◽  
The Poor ◽  
Local Actors ◽  
Distributed Supervisory Control ◽  
Process Coordination ◽  
The Military

Distributed supervisory control systems are characterized by remote supervisors who work through multiple local actors to control a dynamic process. Coordination normally occurs through the use of predetermined plans and procedures. However, these plans and procedures can be underspecified and brittle when an actor is confronted with an unanticipated situation. In these instances, the local actor must adapt the plan in a manner consistent with the intent of the remote supervisor. This research investigated the communication of intent in military C2 systems by using a mixed-fidelity simulation. US army battalion commanders and subordinate company commanders developed operations orders using their standard planning procedures. Anomalies were introduced that forced them to rely on the senior commander's intent rather than the written plan. In spite of an embedded procedure for communicating intent in the military domain, in most instances, company commanders failed to follow their battalion commander's intent. Explanations for the poor performance and methods for imparting presence and communicating intent are discussed. Implications of the study extend to other types of distributed supervisory control systems in which machine agents can function as either remote supervisor or local actor.

The Roma in Post-Communist Bulgaria: Growing Social Marginalization and State Policies

2020 ◽  
Vol 2 (1) ◽  
pp. 1-24
Author(s):  
Yorgos Christidis
Keyword(s):  
Political Parties ◽  
Social Exclusion ◽  
Hate Crime ◽  
Hate Speech ◽  
Poor Performance ◽  
State Policies ◽  
Social Marginalization ◽  
Popular Support ◽  
Economic Problems ◽  
The Poor

This article analyzes the growing impoverishment and marginalization of the Roma in Bulgarian society and the evolution of Bulgaria’s post-1989 policies towards the Roma. It examines the results of the policies so far and the reasons behind the “poor performance” of the policies implemented. It is believed that Post-communist Bulgaria has successfully re-integrated the ethnic Turkish minority given both the assimilation campaign carried out against it in the 1980s and the tragic events that took place in ex-Yugoslavia in the 1990s. This Bulgaria’s successful “ethnic model”, however, has failed to include the Roma. The “Roma issue” has emerged as one of the most serious and intractable ones facing Bulgaria since 1990. A growing part of its population has been living in circumstances of poverty and marginalization that seem only to deteriorate as years go by. State policies that have been introduced since 1999 have failed at large to produce tangible results and to reverse the socio-economic marginalization of the Roma: discrimination, poverty, and social exclusion continue to be the norm. NGOs point out to the fact that many of the measures that have been announced have not been properly implemented, and that legislation existing to tackle discrimination, hate crime, and hate speech is not implemented. Bulgaria’s political parties are averse in dealing with the Roma issue. Policies addressing the socio-economic problems of the Roma, including hate speech and crime, do not enjoy popular support and are seen as politically damaging.

Biomass Characterization in a Nitrification-Denitrification Biological Enhanced Phosphorus Removal (NDBEPR) Plant during Start-Up and Subsequent Periods of Good and Poor Phosphorus Removal

1994 ◽  
Vol 29 (7) ◽  
pp. 91-100 ◽  
Author(s):  
K. C. Lindrea ◽  
S. P. Pigdon ◽  
B. Boyd ◽  
G. A. Lockwood
Keyword(s):  
Phosphorus Removal ◽  
Poor Performance ◽  
Intracellular Distribution ◽  
Full Scale ◽  
Laboratory Scale ◽  
Plant Operation ◽  
The Poor ◽  
Start Up ◽  
Biomass Characterization

During commissioning and process stabilization of a NDBEPR plant at Bendigo intracellular distribution and movement of phosphorus, K+, Mg2+ and Ca2+ was followed to establish the nature of biomass development. The system was also monitored at the end of a period of breakdown of the BEPR process and during its return to phosphorus removal. Phosphorus (P) and Mg2+ distribution in the biomass were closely related during all phases of plant operation, and laboratory trials indicated that the poor performance of the full-scale plant was associated with seasonal reduction in influent Mg2+. Laboratory scale trials produced a similar effect when the influent Mg2+ was limited to concentrations much lower than those experienced in the full scale plant, but only after the Mg2+ and P reserves in the biomass were depleted. The distribution of P, K+, Mg2+ and Ca2+ in the biomass from the full scale plant was similar to that seen in the laboratory trials when cations in the feed were severely limited and recovery of the full scale plant also closely matched that of the laboratory scale system.

Trail Making Test Performance in Relation to Certain Experimenter, Test and Subject Variables

1964 ◽  
Vol 19 (1) ◽  
pp. 199-206 ◽  
Author(s):  
Oscar A. Parsons ◽  
Harriet I. Maslow ◽  
Freda Morris ◽  
J. Peter Denny
Keyword(s):  
Test Performance ◽  
Screening Test ◽  
Poor Performance ◽  
Trail Making Test ◽  
Psychiatric Disturbance ◽  
The Poor ◽  
Subject Variables ◽  
Trail Making ◽  
The Brain ◽  
Order Of Administration

The Trail Making Test, previously reported highly effective in differentiating brain-damaged from non-brain-damaged Ss, was administered to 21 brain-damaged Ss and 63 non-brain-damaged Ss. Since the latter Ss performed at a level indistinguishable from that of the brain-damaged Ss, several studies were designed in an attempt to “explain” the poor performance of the non-brain-damaged Ss. The possible effects of behavioral agitation, anxiety, examiner differences, facility with letters of the alphabet, order of administration, and ego-involvement were investigated. Only anxiety was found to be significantly related to performance. However, in other analyses age, education, vocabulary, and degree of psychiatric disturbance were significantly related to performance. Until these variables are considered in the scoring system, it seems unlikely that the TMT will be effective as a general screening test for brain-damage.

scholarly journals Structural transformation and productivity in Latin America

2015 ◽  
Vol 15 (2) ◽  
Author(s):  
Pedro Cavalcanti Ferreira ◽  
Leonardo Fonseca da Silva
Keyword(s):  
Latin America ◽  
Structural Transformation ◽  
Productivity Growth ◽  
Equilibrium Model ◽  
Poor Performance ◽  
Services Sector ◽  
The Poor ◽  
Agriculture Industry ◽  
Key Factor ◽  
Modern Services

AbstractThis article examines the effects of sectorial shifts and structural transformation on the recent productivity path of Latin America. We use a four-sector (agriculture, industry, modern services and traditional services) general equilibrium model calibrated to the main economies in the region. The model very closely replicates labor reallocations across sectors and the growth of aggregate labor productivity from 1950 to 2005. Structural transformation explains a sizeable portion of the region’s convergence in the first decades. In most cases, the poor performance of the traditional services sector is the main cause of the slowdown in productivity growth observed in the region after the mid-1970s and is a key factor in explaining the divergence during this period.

Optimization Applied to Buzios Flexible Riser Systems and Subsea Layout

2021 ◽  
Author(s):  
Vinicius Gasparetto ◽  
Thierry Hernalsteens ◽  
Joao Francisco Fleck Heck Britto ◽  
Joab Flavio Araujo Leao ◽  
Thiago Duarte Fonseca Dos Santos ◽  
...  
Keyword(s):  
Deep Water ◽  
Technology Use ◽  
Capital Expenditure ◽  
Lessons Learned ◽  
Internal Diameter ◽  
Flexible Riser ◽  
Flexible Pipe ◽  
Injection Wells ◽  
Gas Field ◽  
Field Development

Abstract Buzios is a super-giant ultra-deep-water pre-salt oil and gas field located in the Santos Basin off Brazil's Southeastern coast. There are four production systems already installed in the field. Designed to use flexible pipes to tie back the production and injection wells to the FPSOs (Floating Production Storage and Offloading), these systems have taken advantage from several lessons learned in the previous projects installed by Petrobras in Santos Basin pre-salt areas since 2010. This knowledge, combined with advances in flexible pipe technology, use of long-term contracts and early engagement with suppliers, made it possible to optimize the field development, minimizing the risks and reducing the capital expenditure (CAPEX) initially planned. This paper presents the first four Buzios subsea system developments, highlighting some of the technological achievements applied in the field, as the first wide application of 8" Internal Diameter (ID) flexible production pipes for ultra-deep water, leading to faster ramp-ups and higher production flowrates. It describes how the supply chain strategy provided flexibility to cover the remaining project uncertainties, and reports the optimizations carried out in flexible riser systems and subsea layouts. The flexible risers, usually installed in lazy wave configurations at such water depths, were optimized reducing the total buoyancy necessary. For water injection and service lines, the buoyancy modules were completely removed, and thus the lines were installed in a free-hanging configuration. Riser configuration optimizations promoted a drop of around 25% on total riser CAPEX and allowed the riser anchor position to be placed closer to the floating production unit, promoting opportunities for reducing the subsea tieback lengths. Standardization of pipe specifications and the riser configurations allowed the projects to exchange the lines, increasing flexibility and avoiding riser interference in a scenario with multiple suppliers. Furthermore, Buzios was the first ultra-deep-water project to install a flexible line, riser, and flowline, with fully Controlled Annulus Solution (CAS). This system, developed by TechnipFMC, allows pipe integrity management from the topside, which reduces subsea inspections. As an outcome of the technological improvements and the optimizations applied to the Buzios subsea system, a vast reduction in subsea CAPEX it was achieved, with a swift production ramp-up.

Case History: Lessons learned From Retrieval of Coiled Tubing Stuck by Massive Hydrate Plug When Well Testing in an Ultra Deep Water Gas Well in Mexico

2011 ◽  
Author(s):  
Victor Gerardo Vallejo ◽  
Aciel Olivares ◽  
Pablo Crespo Hdez ◽  
Eduardo R. Roman ◽  
Claudio Rogerio Tigre Maia ◽  
...  
Keyword(s):  
Deep Water ◽  
Case History ◽  
Lessons Learned ◽  
Well Testing ◽  
Gas Well ◽  
Coiled Tubing ◽  
Hydrate Plug ◽  
Water Gas

scholarly journals Fused CLEAN deconvolution for compact and diffuse emission

2018 ◽  
Vol 618 ◽  
pp. A117 ◽  
Author(s):  
L. Zhang
Keyword(s):  
Poor Performance ◽  
Point Of View ◽  
Diffuse Emission ◽  
Multi Scale ◽  
Convolution Operation ◽  
Computational Load ◽  
Fitting Procedure ◽  
The Poor ◽  
Computationally Expensive ◽  
Clean Algorithm

Context. CLEAN algorithms are excellent deconvolution solvers that remove the sidelobes of the dirty beam to clean the dirty image. From the point of view of the scale, there are two types: scale-insensitive CLEAN algorithms, and scale-sensitive CLEAN algorithms. Scale-insensitive CLEAN algorithms perform excellently well for compact emission and perform poorly for diffuse emission, while scale-sensitive CLEAN algorithms are good for both point-like emission and diffuse emission but are often computationally expensive. However, observed images often contain both compact and diffuse emission. An algorithm that can simultaneously process compact and diffuse emission well is therefore required. Aims. We propose a new deconvolution algorithm by combining a scale-insensitive CLEAN algorithm and a scale-sensitive CLEAN algorithm. The new algorithm combines the advantages of scale-insensitive algorithms for compact emission and scale-sensitive algorithms for diffuse emission. At the same time, it avoids the poor performance of scale-insensitive algorithms for diffuse emission and the great computational load of scale-sensitive algorithms for compact emission in residuals. Methods. We propose a fuse mechanism to combine two algorithms: the Asp-Clean2016 algorithm, which solves the computationally expensive problem of convolution operation in the fitting procedure, and the classical Högbom CLEAN (Hg-Clean) algorithm, which is faster and works equally well for compact emission. It is called fused CLEAN (fused-Clean) in this paper. Results. We apply the fused-Clean algorithm to simulated EVLA data and compare it to widely used algorithms: the Hg-Clean algorithm, the multi-scale CLEAN (Ms-Clean), and the Asp-Clean2016 algorithm. The results show that it performs better and is computationally effective.

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