Overview
Rotork actuators provided an all-electric specification for valve control on new gas dehydration units at seven sites in the Transylvanian region of Romania.
Challenge
Romgaz, the largest natural gas producer in Romania, is responsible for the production of around 40% of the country’s consumption. Dehydration plants use triethylene glycol to remove the water from natural gas in to prevent downstream processing problems (such as freezing, corrosion and the formation of hydrates).
Solution
The specification ruled out the use of air instruments and compressors. This dictated the use of explosionproof electric actuators for isolating and control valve duties in the hazardous areas.
Result
Rotork supplied ATEX certified IQT isolating valve actuators and CVA control valve actuators. The electrical supply to the dehydration units is secured by means of a three-tier failsafe system comprising mains power supported by a 30kVA uninterruptable power supply and a 45kVA natural gas powered generator.
Centralised control is provided by a Cytect SCADA system and ABB plc, housed in a control room adjacent to each plant. In addition, an Eex-e certified PC with mimic panel and identical graphical interface is located within each plant, enabling operators to work on the system in the field as well as the control room.
Customer Benefits
This is a key stage of the journey of natural gas. These sites now benefit from precise and accurate control.
The CVA actuators installed offer a highly accurate and responsive method of automating control valves, without the complexity and cost of a pneumatic supply. The IQ is also an electric actuator.
Both designs feature intrinsically safe, non-intrusive setting and configuration technologies.