Digital: Reliability and safety—two sides of the same coin
Digitalization is pervasive in today’s hydrocarbon processing industry.
Digitalization is pervasive in today’s hydrocarbon processing industry. Companies are coming out with offers ranging from point solutions to platforms. They take the forms of sensors, software, wearables, robots and mobile phone applications.
Many technologies are available, but to be effective they must solve a problem. One of the earliest applications is predictive maintenance (PdM). According to a survey by Tech Pro Research in January 2019, 79% of respondents use or plan to use IoT for predictive maintenance.1 This is the highest of any application.
Predictive maintenance is attractive to many companies because it has a fast return on investment. Refineries can immediately see the condition of their assets, which gives benefits in terms of reducing unplanned downtime, increasing safety, reducing maintenance costs, and increasing the intervals between preventive maintenance (PM).
Within the last 5 yr, a shift has been seen in technology that makes online, real-time predictive maintenance more accessible. Wireless sensor prices have dramatically dropped, cloud computing provides scalability and data storage, and advances in machine learning increase the analytical power to make sense of the data. This means that valves, rotating equipment, electrical panels, and other semi-critical assets can be monitored.
While unplanned downtime is usually the primary driver for wireless PdM, it can have a significant impact on reducing safety risk. In general, four scenarios are frequently identified where real-time asset information can lead to safer operations, as detailed in the following sections.
Fewer “unusual situations”
The most dangerous time for a refinery is when it is in transition. According to a 1998 study of 500 safety incidents, “A typical refining or petrochemical facility will spend less than 10% of its time in transient operations; yet, more than 50% of process safety incidents occur during these operations.”2 One of the reasons for this is that people spend most of their time in normal operating conditions, and they are not practiced enough in abnormal conditions. Tens of thousands of procedures are performed during a refinery turnaround; an error in any one of these could cause a serious safety incident.
The deadliest refinery accident in US history happened at BP’s Texas City plant in 2005, during the restart of the hydrocarbon isomerization unit. Multiple explosions and fire caused 15 deaths and 180 injuries. According to an investigation by the US Chemical Safety Board (CSB), there were many cultural, equipment, safety and human causes for the accident.
PM tasks are often set by original equipment manufacturers (OEMs) or a criticality analysis. Sensorizing assets and being notified of any changes allows maintenance teams to extend the intervals between PMs. For example, instead of rebuilding a pump on a schedule, real-time asset condition monitoring can allow for rebuilding it only as needed. This results in not only significant cost savings, but also a reduction in abnormal situations and an increase in safety.
Reliable operations with minimal shutdowns and startups for maintenance activities is a major contributor to reducing safety incidents.
Improved process safety
In 2017, there were at least 33 fires, explosions and chemical releases at US oil refineries and industrial plants.3 After the BP Texas City explosion, OSHA officials found that oil refineries accounted for more worker deaths than any other industry category. Seventy percent of citations were related to process safety.
Most oil and gas facilities have protection systems on critical assets and periodic walkaround condition monitoring programs for semi-critical assets. Even with well-developed reliability programs, accidents happen. By increasing the number of balance of plant (BOP) assets being monitored, operational reliability improves along with safety.
Less accidents
Every facility has assets that are inaccessible or dangerous to reach with walkaround vibration monitoring equipment—e.g., areas where machinery is gummed up with hydrocarbon residue or monitoring cooling tower equipment. Accidents can cause burns or death.
Instead of risking human lives for inspections, many companies can easily justify installing permanent sensors on these assets. They can regularly receive data on asset condition without crawling around hazardous equipment.
Better scheduling of service personnel
Service scheduling is especially relevant to operators with distributed assets, like a midstream compressor station. One pipeline operator shared that the immediate benefit from continuous wireless sensors and real-time asset information was that he did not need to dispatch service personnel to check on the asset condition.
As a major operator in Colorado, the winter months bring heavy snowfall, which can mean dangerous conditions for inspection. The gas plant that the pipeline supplied was not receiving enough feedstock, and a technician was sent to inspect it. The technician was involved in an auto accident due to the road conditions.
If sensors had been monitoring the compressor health, the technician could have been notified earlier, resulting in better scheduling under safer conditions.
Better reliability equals better safety
Most refineries install condition monitoring because the cost of lost production can amount to millions of dollars per day. A failure in a production-critical asset has significant consequences, and maintenance teams want to see asset condition to predict and prevent unplanned shutdowns.
The side benefit of safety could be argued to be the primary benefit. Ultimately, better-running machinery means improved safety. The consequences of failure are often so high that preventing one safety incident could pay back the entire system. The OSHA fine alone for the Texas City refinery explosion was $50.6 MM. This amount does not include the civil suits or the investments BP is making to improve working conditions.
Real-time asset condition goes beyond safety
Real-time asset condition provides transparency across the entire facility so that everyone, from maintenance technicians to the plant manager, can see what is happening in the refinery. Operators are immediately notified of the earliest changes in asset condition and can view conditions at any time, from anywhere.
Collecting more data means that someone needs to analyze it. One company collected 1.4 MM readings with permanent wireless sensors, compared with 5,000 that an analyst would have collected in the same 6 mos. The sheer volume of data would be unmanageable for a team of analysts collecting data every few weeks.
Machine learning algorithms can sort through huge quantities of data, acting as an assistant to the analyst. They can create a single, trendable asset health score that flags problem assets.
Continuous sensors can go beyond predicting health to optimizing asset performance. By correlating asset conditions with process conditions, the system can identify abnormal variations before they cause problems in mechanical equipment.
One example is pump optimization. Periodic monitoring of vibration alone will not determine whether the pump is operating below its best efficiency point. Instead, multiple parameters are needed to understand performance.
Digitalization
An explosion in digital technologies is being seen. Refineries that are implementing digitalization initiatives should start with their business goals to understand the best application of these technologies.
When it comes to asset reliability, real-time information can increase predictability, reduce costs and, most importantly, save lives. Hindsight is always 20/20, and digital refineries have the opportunity to implement technology that changes the term “hindsight” to “foresight.” HP
Literature cited
- Wachsman, M. W., “Survey: Industrial IoT deployment thriving,” ZDNet, March 1, 2019, online: www.zdnet.com/article/survey-industrial-iot-deployment-thriving/
- Miklovic, D., “Why 10% of your operations cause 50% of your safety incidents,” LNS Research, Industrial Transformation Blog, January 26, 2016, online: www.blog.lnsresearch.com/why-10-of-your-operations-cause-50-of-your-safety-incidents
- Green, N., “33 accidents happened at oil refineries as EPA delayed updating disaster rule, says environmentalist group,” Daily Breeze, April 3, 2018, online: www.dailybreeze.com/2018/04/03/environmentalists-blast-epa-for-inaction-on-rule-update-intended-to-bolster-refinery-safety/
The Author
Madsen, K. - Petasense,
Ken Madsen is a Senior Account Executive at Petasense. He has more than 20 yr of experience in enterprise sales working with oil and gas companies across upstream, midstream and downstream segments. He excels at transforming complex technologies like the IIoT into a solution that solves real business challenges. Previously, he worked at Emerson’s Process Systems and Solutions group, where he implemented a sales enablement program. Mr. Madsen holds an MBA degree from Kellogg University in Evanston, Illinois and a BS degree in civil engineering from Rice University in Houston, Texas.
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