Technology for a better society 1

Nicola Paltrinieri1, Giordano Emrys Scarponi1,2, Faisal Khan3, Stein Hauge1

1SINTEF Technology and Society, Trondheim, Norway.

2University of Bologna, Italy

3Memorial University of Newfoundland, St. John’s, Canada

Addressing Dynamic Risk in the Petroleum Industry by Means of Innovative Analysis Solutions

6th International Conference on Safety & Environment inProcess & Power Industry - 13-16 April, 2014, Bologna , Italy

Technology for a better society 2

Every event was unique and the direct causes often differed, but many of the underlying causes were identified as recurring problems, such as:

• the failure to perform risk evaluation during changes/modifications, and• the inadequate verification of safety barriers

(Tinmannsvik et al. 2011)In particular it was reported:• poor information flow between night and dayshifts and onshore and offshore teams

operating at Montara, Macondo and Snorre A, and• poor involvement of measured pressure drilling experts in the planning, risk

assessment and operational follow-up of the Gullfaks C well operation.

Snorre A 2004 Montara 2009 Macondo 2010 Gullfaks C 2010

Recent O&G industry accidentsIntroduction

Technology for a better society 3

In the Petroleum industry, Integrated operations (IO) refers to new work processes and ways of performing oil and gas exploration and production, which has been facilitated by new information and communication technology.The IO Center conducts research, innovation and education within the field of IO.

Data processing, modeling, prediction

Data acquisition

Visualization &communication

Smarter Decisions through

Integrated operations

Integrated planning & execution

Decision processes across disciplines &

organizations

Integrated OperationsIntroduction

Technology for a better society

Three innovative techniques, whose main feature is their dynamicity and capacity to be reiterated and produce updated risk assessment, are applied and evaluated for their potential suitability with IO solutions and related implications.

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New dynamic risk approaches

1. Establishing the context

2. Hazard identification

3. Analysis of initiating events

4. Analysis of consequences

5. Establishing the risk picture

6. Risk evaluation

7. Comm

unic. &

consultation

8. Monitoring, review

and update

DyPASI Dynamic Risk Analysis Risk Barometer

Methodology

NORSOK Z-013 standard steps

Methods

Novelties

Technology for a better society 5

Dynamic Procedure for Atypical Scenarios Identification

Step Description

1 Retrieval of risk notions

Search for relevant information on undetected potential hazards and accident scenarios not considered in the bow-tie development.

2 PrioritizationDetermination as to whether the data are significant enough to trigger further action and proceed with risk assessment.

3Atypical scenario identification

Atypical scenarios are isolated from the early warnings and a cause-consequence chain is developed and integrated into the bow-tie d.

4 Definition of safety measures

Definition of new barriers related to atypical scenario elements.

Methodology

Pre-requirements

As a preliminary activity the application of the conventional bow-tie technique is performed.

Technology for a better society 6

Dynamic Risk AnalysisStep Description

1Scenario identification. The potential scenarios, their consequences, causes and related safety barriers are identified by means of a Bow-Tie Analysis.

2Prior function calculation. A probability density function of type Beta can be selected to represent the failure probability of safety barriers. Its mean value can be used as a conditional probability in the frequency analysis.

3Formation of the likelihood function. This function is formed using real time data from the process as it operates. These data are inferred from the Accident Sequence Precursors and presented by a binomial distribution.

4Posterior function calculation. The posterior failure function of the safety barriers is obtained from the prior and likelihood functions using Bayesian inference. Bayesian inference is a tool which uses data to improve an estimate of a parameter.

5 Consequence analysis. It is carried out on the scenario in order to estimate its potential consequences.

Methodology

Pre-requirements

Monitoring and report of process incidents and near misses (Accident Sequence Precursors – ASP).

Technology for a better society 7

Risk BarometerStep Description Formula

1Risk indicators can be measured on an arbitrary scale but values should be mapped by means of a standardized mark scale.

2 Definition of RIF values. Linear weighted sum is used.

3Definition of RIFs impact on QRA parameter. Linear weighted sum is used.

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Development of QRA parameter influence model. The relation between the total weighted RIF value and the parameter is established by a linear interpolation.

5 Risk measure expansion by Taylor series.

6 Visualization through risk barometer.

Methodology

Pre-requirements

Sensitivity analysis of QRA to define relative importance of QRA parameters

Definition of RIFs related to QRA parameters

Definition of risk indicators related to RIFs.

Technology for a better society

The case-study is a typical oil production process area located topside on an offshore platform. The process area consists of the following separate modules:• Choke/manifold

module• Separation module• Gas compression

module• Gas recompression

module• Water

injection/production module

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Case-study: oil production process areaApplication

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The following search systems were used to identify related risk notions: • MHIDAS, (HSE – United Kingdom), • ARIA (French Ministry of Environment), and • Google Scholar (Google inc.).

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Data retrieval Results

Explosion Fire Release Other Tot

Disaster 3 3

Accident 8 6 1 15

Incident 4 6 2 12

Mishap 2 1 6 9

Tot 17 13 8 1

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Logic tree diagram

detect limit detect control control detect limit controlleak leak pool pool ign gas gas dis pool dis

safe safe

safe pool disp. environ. / tox.

Pool gas disp. flashfire/VCE flashfire/VCE ignition Poolfire safe

pool disp. environ. / tox.

gas disp. flashfire/VCE flashfire/VCE ignition Poolfire

Results

Detail of the bow-tie diagram (right-hand side) referring to a multiphase loss of containment in the 1st stage separator.

LOC

COND. PROB. COND.

PROB.COND. PROB.

COND. PROB.

COND. PROB.

COND. PROB.

COND. PROB.

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Posterior frequency of accident scenariosResults

0.00E+00

5.00E-08

1.00E-07

1.50E-07

2.00E-07

2.50E-07

3.00E-07

3.50E-07

0 2 4 6 8 10 12

Env. tox.Flashfire/VCEPoolfire

Ev./

year

Year

On the basis of the risk notions identified, some fictional accident sequence precursors were defined in order to show the application of DRA.

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A set of indicators defining the status of the safety barriers in

the process area and organizational influencing

factors was defined. Average values with representative

variations were applied.

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Definition of indicatorsResults

Indicator

QRA parameter:

Barrier PFD

RIF:Technical measures

RIF:Operational measures

RIF:Organizational

measures

Theory

Leak frequency

Technical condition

Competence & training

Preparations and planning

Work practice and work load

Work supervision / management

Quality of procedures and documentation

Preventrelease

PSD system

PSVs

Containment of process segments

Disassembling of HC-system

Practice (actual oil company

case-study)

Technology for a better society 13

Real-time risk levelIndicator description wi,j,k

xi,j,k Marktp ti tp ti

Findings during 3 last months that resulted in notification, maintenance request or project

15% 1 2 3.5 6

Open work permits for a given area 13% 3 6 3.5 6

Bypasses and overrides/inhibitions of the gas detection system

33% 1 2 3.5 6

Fraction of failed valve tests 25% 1% 2% 1 3.5

Etc…

Low risk

Normal risk

High risk

Very high risk

High high risk

ti

tp

Results

Technology for a better society

DyPASI and DRA demonstrated to be mutually complementary and to give a relatively effective support to the continuous review and update of the risk picture.

DyPASI and DRA are still relatively tied to the QRA structure, but the Risk Barometer aims to overtake and improve the QRA process by introducing new risk influencing factors.

Both DRA and Risk Barometer aim to evaluate how the performance of the safety barriers in the plant affects the overall risk picture, but they respectively adopt a reactive and proactive approach.

The Risk Barometer aims to effectively visualize the result, in order to provide a better decision support during daily operations.

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Qualitative assessment of the techniquesDiscussion

Technology for a better society

All techniques were effectively applied to the generic case-study considered.

A clear complementarity between the different approaches was not identified because of overlaps and different strategies adopted in the assessment of the risk picture.

The Risk Barometer, despite the fact it is still under development, was proven to be the most suitable technique to dynamically assess the risk in the context of Integrated Operations.

In fact, it is based on indicators that can be automatically collected from the system, in order to give a real-time response, and addresses the issue of the visualization of results, in order to share information across geographical, organizational and discipline boundaries as a support for critical decision-making.

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ConclusionsConclusions