Asset Management in the Chemical Industry

Many high-hazard chemical plants around the world have been in operation for 30 to 40 years. As these plants surpass or approach their original design life, it is crucial to demonstrate their continued viability to stakeholders and regulators, in many cases to ensure the highest levels of Process Safety Management are maintained, but also to ensure that Overall Equipment Effectiveness (OEE) is in good shape.

Aging

The age of equipment alone is not a reliable measure for assessing its suitability for continued use. Aging involves a range of physical, operational, and engineering factors that significantly impact equipment lifespan. In many cases, life-limiting factors were embedded in the design due to capital cost considerations. However, studies show that around 50% of failures are due to operating and maintenance practices, which can be controlled and managed. Understanding the current condition and deterioration rate of equipment is vital for ensuring its ongoing safety and reliability.

?Asset Life Studies of Chemical Plants

Such studies aim to identify short, medium, and long-term actions and costs for continued operation. They focus on vulnerabilities to aging and potential life-limiting issues, using information from asset operators and site visits. The studies review equipment conditions and consider asset care measures, such as inspections and preventative maintenance. Objectives usually include investigating plant conditions, determining additional investment needs, minimizing inspection and maintenance costs, and prioritizing actions to address identified gaps. Key questions for specialists include assessing equipment fitness, necessary actions, expenditure, targeting, planning, prioritization, and vulnerability.

?Methodology

The scope of studies varies from whole sites to specific plant areas or equipment classes. A team of specialists and subject matter experts follow a proven methodology, starting with asset identification and information collection from various sources. Assessments determine the ability to operate equipment to its projected retirement date, categorizing equipment into different statuses based on necessary maintenance and repair. Gaps are identified by comparing required measures to existing maintenance programs, with recommendations formulated and cost estimated. Recommendations are prioritized and scheduled, with a full list provided for asset remediation projects. Finalized asset life plans detail necessary actions for continued safe operation.

Identification of the assets and equipment in scope

The starting point for any study is to identify the assets to be covered by the study.

At the next level, it is necessary to find out which equipment is located within, or associated with, which system. The common facilities and utilities are also identified.

Within each of the systems and the common facilities, it is necessary to identify which equipment is in service and what date it is required to operate to, recognizing that some of the equipment may be redundant or retired early.

On the basis of this information, the study team is then able to determine how to approach the assessment of the equipment. For example, larger items of equipment, such as pressure vessels, are generally assessed individually while instrumentation is often treated as a population.

Information Collection

The information necessary for the study should be assembled from a variety of data sources including asset registers, drawings, photographs and inspection and maintenance records. This is supplemented by discussions with the operations and maintenance personnel responsible for the asset.

Assessment and Categorisation of the Equipment

An assessment can then be made of the ability to continue to operate the equipment to its projected retirement date. This assessment is based upon knowledge of the current condition of the equipment, the known / likely deterioration mechanisms and other life-limiting factors (such as obsolescence) and the ability to maintain the equipment in a reliable and serviceable condition over the operational life of the asset, and beyond. The assessment draws heavily upon the knowledge and experience of the specialists and subject matter experts.

A key output of the assessment is a confirmation of the ongoing maintenance and inspection requirements for the equipment. The assessment also establishes whether the necessary measures are in place.

The asset life status of the equipment is then defined and categorized:

1. Equipment requiring replacement within the remaining operational life of the asset
2. Equipment requiring major repair for continued operation
3. Equipment requiring additional minor (but significant) repair for continued operation
4. Equipment for which continuation of maintenance and inspection regimes is sufficient
5. Equipment requiring further information / study

Categorization of Equipment Asset Life Status

Typical examples of Category 1 include the replacement of vessels, pump sets and safety systems (i.e. a major upgrade of a fire system). Category 2 typically includes major repairs to vessels and tanks, the replacement of sections of pipework and extensive fabric maintenance. Minor modifications and localized repainting and re-lagging are examples of Category 3.

Category 4 covers the equipment for which continuation of the existing maintenance and inspection regimes is deemed to be sufficient to maintain the equipment in a reliable and serviceable condition. .

It is not always possible to determine the asset life status of all of the equipment. More detailed inspection and / or specialist studies may be necessary to provide sufficient knowledge upon which to base the assessment.

Identification of Gaps and Recommendations

The identification of the gaps is based upon a comparison of the measures required to sustain the safety and reliability of the equipment over its projected operating life. The annual maintenance programs and the turnaround program are important inputs into this process.

Most assets have an ongoing fabric maintenance campaign. Understanding the scope of this program and the rate of progress relative to the size of the overall task is also important. This is, in effect, a judgment as to whether the operator is managing to paint the asset faster than it is rusting!

In addition to this, the project program is reviewed to identify projects covering major maintenance (replacements and refurbishments) and any planned modifications.

Having completed this comparison the recommendations to address the gaps can then be formulated.

Estimation of the Cost to Implement the Recommendations

The cost of implementing each recommendation is estimated. Any assumptions made in order to produce the estimates are recorded with the recommendation, together with equipment costs and the installation factors used.

Prioritize the Recommendations and Propose a Timeline

Prioritization and timing of the recommendations involve striking a balance between risk and an assessment of when it is practicable to have completed the recommendation. The risk assessment includes HSE & PSM risk, as well as business risk. The risk assessments are based on the operator’s risk assessment models used within their business.

Finalization of the Equipment Asset Life Plans

Having validated the study findings and recommendations the specialist consultants are then able to complete the asset life plans. The asset life plan includes a description of the equipment, its specification and construction, together with a summary of the operation and maintenance history with a particular emphasis on the age-related deterioration mechanisms. The plan also records the findings and outcome of the risk assessment and the asset life categorization. The plan gives an authoritative review of the equipment and states what actions are necessary for the continued safe and reliable operation of the equipment for the remaining life of the asset.

In summary, each asset life plan is a clear statement of the way forward for the equipment.

Generation of the Expenditure Projection

The data within the recommendations spreadsheet is used as the basis for the creation of the expenditure projection

Reporting and Implementation

A report summarizing findings and recommendations should be prepared, forming part of the asset life plans. Implementation planning and embedding changes across operations ensure the benefits of the study can be realized. This may involve further studies, project scoping, and changes to maintenance and inspection practices.

Benefits

Asset Life Studies are essential for strategic business planning, providing cost information and expenditure profiles valued by operators. They confirm the technical feasibility and safety of ongoing operations to regulators and stakeholders and identify necessary work programs. These studies also enhance understanding of aging issues and management measures within engineering and operations teams.