PTQ Q2 2026 Issue

Operations and process engineering need to feed back their issues and provide the data needed to justify their turnaround scope items, such as: • Small auxiliary equipment critical to operations. • Equipment that is difficult to monitor and inspect. • Areas with limited instrumentation and access. • Problems caused during unit upsets or shutdowns. Other areas may require added monitoring to quantify the issue and then apply a value to justify the turnaround scope. Without data and operation support, it is easy for the turnaround group to cut these items to control scope. The following discussion provides examples of critical areas that have significant value. Small auxiliary equipment Vacuum eductors on condensing turbines have limited instrumentation, making it difficult to track conditions. Issues such as abnormal designs can cause challenges in maintaining them while in service. Assumptions that this equipment can be maintained during operations can sud- denly change when isolation valves fail to hold. Tracking the performance of small equipment, when fea - sible, can provide justification for cleaning the equipment. For example, turbine and vacuum eductor performance can be used to justify the loss of air rate from poor turbine per- formance. In one case, the loss of blower capacity resulted in a 5% reduction in unit capacity, valued at ~$4.6 MM/yr. Figure 1 shows the eductor surface condenser found in poor condition during shutdown. Hard-to-monitor or inspect equipment The regenerator overhead orifice chamber is used to reduce pressure without causing excessive wear on the flue gas slide valves (FGSV). Often, pressure data across the orifice chamber is not available. An issue with the orifice cham - ber may not be clear until the flue gas slide valve operates well away from normal opening. Even then, it may first be assumed that the process side conditions are the cause or that there is an issue with the slide valve, such as excessive wear. Inspection during a turnaround may also be difficult with welded manways, which makes the turnaround group reluctant to authorise opening the equipment. Tracking both the FGSV and orifice chamber pressure drop based on actual flow can help identify issues. Consider providing sufficient online pressure data to track both the FGSV and orifice chamber. Issues with the orifice chamber

degradation in fractionation, loss of flow, and/or increased pressure drop. This is the time to submit the list of process equipment concerns. Armed with this data, the next task is to develop the operation cost of the issue. Replacing a leaking valve is often easily justified by the lack of isolation and loss of that piece of equipment, which may result in a full unit outage. Estimates of unit throughput loss or heat transfer loss can be generated based on the loss of performance. Unit models can also be used to show performance at design conditions versus current operation. Data col - lected from a post-turnaround test run can also be used for benchmark operations. This is also an opportunity to identify upgrades to equipment to remove constraints, reduce equipment downtime, or reduce operating costs. Any equipment that is chosen for replacement should be reviewed for improvement opportunities. Process engineering should also query operations for issues they have noted. Engineering will likely be called upon to help in justifying operations items for the turnaround. Historically, turnaround scope has been driven by mechani - cal integrity and base-level inspection programmes. Reliability-based inspection programmes, such as API RP 580/581 Risked-Based Inspection, have developed, and inspection data has been used to predict mechanical integrity issues. From the programmes, inspection can focus on damage mechanisms and corrosion issues. These programmes can then improve mechanical reliability while reducing turnaround scope, but they are not designed to find process and operating issues. Figure 1 As found, eductor surface condenser exchanger condition

No individual tray ∆Ps

Tray eroded

Welded manways: Dicult to access

Nozzle holes

Figure 2 Damage in orifice chamber

PTQ Q2 2026