VITAL ROLE Compressor recycle valves, also called anti-surge valves, play a vital role in safeguarding the compressor against expensive damage
Increasingly demanding dynamic performance requirements and targets to reduce plant emissions are placing compressor equipment at risk of damage, but proven anti-surge and compressor recycle valve technology is set to help the oil and gas industry avoid compressor damage and, consequently, reduce downtime.
Compressor recycle valves, also called anti-surge valves, play a vital role in safeguarding the compressor against expensive damage by redirecting the outlet gas back to its inlet.
The valve comprises two essential components: the valve assembly, which serves as the critical mechanical part, and the advanced pneumatic actuator, which features a high-performing and fast-acting controller.
To ensure improved performance and effectively tackle significant concerns, such as vibration, noise and controllability, the anti-surge control valve relies on a fully integrated and proven technology. Employing this comprehensive approach enables the valve to achieve peak performance and successfully address critical issues in applicable systems, specialist flow control solutions provider IMI Critical Engineering says.
IMI CCI application engineering manager Ronald Simon says the performance of an anti-surge valve is crucial for compressor and plant performance.
“To maintain an optimal balance between efficient production and the proper functioning of a compressor, seamless coordination among all components of a compressor recycle valve is essential.”
The faster and more precise the anti-surge control valve's response to an upset condition on the compressor map, the lower the process interruption and the likelihood of repetitive surge events, he adds.
This, in turn, reduces the risk of compressor damage, resulting in enhanced performance, reliability and production output for the plant.
However, surge events can interrupt compression in upstream and midstream oil and gas, liquefied natural gas, and petrochemicals facilities.
If left unaddressed, this disruption may lead to compressor trips or system failures that require, often times, expensive remedial work to resolve the damage, notes IMI Critical Engineering global engineering director Mike Semens-Flanagan.
To reduce recycling modes on the compressor and ensure the best protection, he says, it is crucial to prioritise dynamic performance and controllability.
“By achieving this, the system can effectively and efficiently reduce the occurrence of recycling modes, thus maximising operational efficiency,” Simon says.
Meanwhile, Semens-Flanagan highlights that, in demanding applications, the valve manages high dynamic forces, so failure risks must be reduced for the best possible performance.
Similarly, valve issues, including vibration, noise and erosion caused by the wide differential pressures that occur during these operations, can impact on nearby equipment if not addressed, he adds.
To address these concerns, IMI Critical Engineering has developed an integrated anti-surge and compressor recycle valve that combines multiple, co-acting technologies to balance efficient production and equipment health.
The valve comprises IMI CCI’s patented DRAG Control Valve technology with supply chain visibility actuators and smart, high-performance FasTrak or QuickTrak controllers and positioners.
The solution’s individual parts, developed in-house across the business divisions of the IMI group, continually interact to reduce the chance of cycle trips to improve performance at startup and during operation.
The multi-stage, multi-path DRAG design directs fluid through a highly-resistant tortuous path to incrementally reduce the differential pressure. This limits the velocity head at the trim, which eliminates the risk of vibration, noise and erosion.
The QuickTrak controller features the latest pneumatic digital valve control technology, Simon says, adding that the QuickTrak system is designed to meet the needs of the most demanding applications.
“Perfectly integrated with the SC/V actuator, it provides fast and highly accurate valve control,” he says.
Another precise digital-pneumatic valve controller is the company’s FasTrak, which reacts to changing conditions within the valve, thereby preventing issues and supporting predictive maintenance.
“It also comes with a dedicated diagnostic system for anti-surge applications and a packing degradation monitoring system,” Simon highlights.
The valve, designed for operations in the oil and gas sector, incorporates a high number of stages for small openings at low flow conditions. This design allows for greater velocity and flow control, which Simon says results in fewer cycles required to achieve compression targets and, ultimately, reduces the carbon footprint.
The integrated solution offers numerous benefits, including uninterrupted processes during surge events, and subsequently mitigating the risk of repeatable surge events and compressor trips.