Feature article
Meeting the asset-integrity challenge
16/05/2008
Elise Tjong Tjin Tai, Shell Global Solutions International BV
Most process-industry companies pride themselves on their good safety records.
Indeed, their operating licences depend on their ability to demonstrate that safety procedures are in place and that equipment is being maintained to a high standard. But many plants have long operating histories and a wide variety of assets of differing ages and types, which can make asset-integrity management challenging. And many assets are now being operated beyond their envisaged design lives.
Without a thorough knowledge of the condition of a plant’s critical equipment and an understanding of its repair and replacement needs, companies can find it difficult to incorporate asset-integrity and equipment budgets into long-term business plans. They may also be under pressure to demonstrate the effectiveness of their asset-integrity measures to stakeholders and regulatory authorities.
Asset-integrity is a key contributor to successful operational performance. Two kinds of asset-integrity reviews are routinely performed, the first type of review focuses on management systems and the second concentrates on equipment and hardware systems. These independent tasks are often combined to give a comprehensive insight into the asset’s integrity.
This article uses four case studies to illustrate the benefits of performing a focused asset-integrity review to establish the nature of any long- and short-term hardware and management issues and to prioritise investment.
Focused asset-integrity review
A focused asset-integrity review enables managers to identify more efficient ways of working by learning from successful implementation of new strategies in similar facilities around the world. Each review involves a close partnership between a dedicated external team and a team from the company whose equipment and/or management systems are being reviewed. There are four key stages in the review:
- For a management-systems review, the company carries out a preliminary self-assessment of its operations, using a question-and-answer software package.
- The review team interviews employees at all levels in the organisation, evaluates the findings and compares them with the customer’s self-assessment. The team assesses the condition of the hardware through inspection during site walks, and reviewing maintenance and inspection records.
- The company receives a score (on a scale of 0 to 1000) that benchmarks its asset-integrity management systems against those of other companies with similar facilities. This highlights the company’s strengths and the opportunities for improvement.
- The review team works within the client’s organisation to identify where the differences lie and to prepare a target list of improvements of the integrity management systems. For hardware improvements, recommendations are defined and prioritised.
The review is a vital step toward helping improve asset integrity and prioritising areas for future development. Operating expenditure can also be targeted to help maximise the benefits. Asset integrity can be improved through the implementation of technical and operational recommendations. The benefits may include
- an accurate determination of existing asset-integrity management systems
- detailed practical recommendations for integrity management systems, equipment and hardware systems improvements that are based on the external team members’ extensive knowledge of asset integrity
- compelling evidence to demonstrate the effectiveness of asset-integrity measures to stakeholders and regulatory authorities
- on-the-job training opportunities for staff to participate in the review, learn from the specialist and follow up the recommendations made during the review
- global networking opportunities, such as best-practice exchanges between operating units that have undergone a similar review or the establishment of specialist engineering networks and joint improvement programmes.
This asset-integrity review system has been successfully applied for over 10 years in refineries, chemical plants, liquefied natural gas (LNG) plants, gas plants, and exploration and production facilities worldwide.
German fired equipment
The Harburg refinery, operated by Shell Deutschland Oil GmbH, is one of Germany’s oldest refineries, and has a wide variety of fired equipment with different safeguarding systems. Harburg refinery wanted its fired equipment to continue operating safely and reliably and to be ready for a forthcoming government integrity-management policy.
In 2004, a multidisciplinary team performed a focused asset-integrity review that centered on the refinery’s fired equipment. The programme had three steps: review, implement and sustain. During the review stage, the team assessed and challenged the status of the refinery’s fired equipment and its integrity-management systems. The team members applied their specialist maintenance, engineering and operational experience to evaluating issues in areas that included combustion, operations, process technology, inspection, materials and corrosion, process control and safeguarding.
The review team interviewed key refinery staff and contractors, assessed plant records and viewed the equipment. The results were then scored and weighted, and used to systematically evaluate the fired equipment against current best-practice technical and operational standards for long-term integrity. For example, the presence of effective safeguarding systems and flame detectors was given a high weighting, and the existence and appropriate management of integrity operating windows was considered crucial.
The key recommendations from the review included upgrading the management of the integrity operating windows and revising start-up procedures and burner maintenance protocols. Many of the maintenance recommendations relating to items such as burners, heater observation windows and mechanical minimum stops for stack dampers were easy to implement but, together, they delivered considerable benefits. The review also demonstrated that some of the fired equipment could benefit from thermographic and metallographic examinations and consequent material replacement.
The refinery’s management was given a concise overview of the status of the fired equipment, the areas for improvement and recommendations for risk-prioritised actions to help realise these improvements.
The review team found that Harburg refinery’s fired equipment was generally in good condition and had suitable management systems and well-trained operators and process engineers. Some of the review’s recommendations supported the refinery staff’s insights into what improvements were necessary. For example, the review identified the need and supported the approval of a new $35-million furnace, which was commissioned in May 2006. Replacing the furnace was shown to be vital for the refinery’s long-term integrity goals.
Other opportunities for improvement were identified with the help of the fresh perspective that the external reviewers brought to Harburg refinery. The review also provided credible evidence of the effectiveness of the refinery’s asset-integrity measures to stakeholders and regulatory authorities.
A similar review was undertaken at Rheinland refinery, Germany, which is also operated by Shell Deutschland Oil GmbH. A business improvement review had identified the reliability of fired equipment as an area that could be improved. One of the employees had participated in a focused asset-integrity review at another refinery and had seen the benefits of the process. In 2005, Rheinland refinery initiated its own review.
Brunei LNG plant rejuvenation
Brunei’s natural gas is liquefied for export at the Brunei LNG plant, which is operated by Brunei LNG Sdn Bhd (BLNG). The plant was designed in the late sixties and increasing its capacity and extending its operating life are long-term projects for BLNG. In the late 1980s the plant underwent a major rejuvenation.
The rejuvenation work was performed at a cost of only 15–20% of the asset replacement value. Following the success of a reliability and integrity improvement programme, a second study was performed in the late 1990s to assess whether the life of the plant could be extended a further 20 years to 60 years. The study, named ‘asset reference plan’, was based on input from several sources, among this were the results of an asset integrity review focused on equipment and hardware systems. It concluded that the proposed extension of the plant’s life was feasible. Twenty-five major projects were to be implemented over 10 years, including a new power plant, the upgrade of the cooling water system and the replacement of many components, such as safety relief valves, control valves, instrumentation, high voltage cabling etc. Replacing the four Main Cryogenic Heat Exchangers (MCHE) was one of the first major projects to be undertaken: two MCHEs were started up in 2004 and the remaining two in 2005.
Rejuvenation work is ongoing at the Lumut plant. All this work is designed to provide a renovated, up-to-standard plant capable of producing more than 140% of original nameplate capacity for a period of at least 20 years, all this at a ‘rejuvenation’ cost substantially lower than the cost for a new LNG plant.
Focused asset-integrity reviews of integrity management systems, which are carried out typically every five years at BLNG, as part of the assurance programme, have been instrumental in the planning of the rejuvenation efforts. In addition, the reviews helped BLNG to evaluate and improve the plant’s asset-integrity management, and, at the same time, reduce costs to compete with other LNG exporters in Asia–Pacific. It also allowed BLNG to benchmark the plant’s asset-integrity management to confirm that the systems and processes in place were efficient and to identify any areas for improvement. Focused asset-integrity reviews are seen as an opportunity to obtain confirmation that the operation is heading in the right direction.
Brunei oil and gas production
Brunei is the third-largest oil producer in Southeast Asia, and its production averages about 200,000 B/D. Brunei Shell Petroleum (BSP), a joint venture owned in equal shares by the Brunei government and Royal Dutch Shell plc, is the chief oil and gas company in Brunei.
The management of BSP was facing the challenge to determine whether the aging assets would meet future business targets, and they recognised that a focused asset-integrity review would effectively identify the issues to be tackled. The company knew that a good integrity management system can help to prevent avoidable losses and protect a company’s reputation.
BSP undertook a focused asset-integrity review that enabled it to identify a clear path toward future improvements. The programme looked at the management systems at BSP’s upstream facilities. BSP was able to confirm and set priorities for improvement and adjust its asset-management focus areas. In addition, benchmarking between operating units helped BSP to identify where best to concentrate expenditure.
The review has been key to the Shell Exploration and Production Technical Integrity programme, which consists of three parts, assess, fix and sustain. Completing the review has been key to the delivery of the ‘assess’ part of the programme. It has confirmed that the company is moving toward top-quartile performance and highlighted further opportunities for improvement; the management of lifting equipment was one area identified, with both short and long-term action items being defined. Clear goals were set for improving asset-management systems, and the company is well on its way to meeting them.
Conclusion
The reviews at these facilities described above demonstrate the value that a thorough knowledge, gained through applying a structured methodology, of the condition of a plant’s critical equipment and asset-integrity management systems can deliver. Indeed, most facilities are now initiating additional focused asset-integrity reviews for their equipment and management systems.
The asset-integrity reviews helped provide the foundations on which the improvement plans for asset-integrity management systems have been built. They have also been important steps towards the implementation of rejuvenation plans.
The author
Elise Tjong Tjin Tai is a senior engineer for asset integrity and reliability at Shell Global Solutions International BV, The Hague, the Netherlands. Before joining Shell Global Solutions, she worked in Shell refinery and chemical plants in the Netherlands. She has an MSc degree in mechanical engineering from the University of Twente, the Netherlands.