Rashid Petroleum Company (Rashpetco) is the key supplier of gas for both domestic consumption and as a feedstock to local LNG plants exporting around the world. Frequent production issues during recent years had prompted a number of reviews of systems and procedures, equipment, and facilities. One such review was carried out on the alarm system where the number of alarms being presented to the Control Room Operators (CRO’s) was well outside the guidelines defined in EEMUA 191, the internationally recognised guide to good practice in alarm management. This was identified as a key problem both for maintaining production and for improving safety.
A number of previous attempts to reduce the number of alarms had proven to be unsuccessful and failure to respond to alarms had been implicated in a number of compressor trips that resulted in production losses. Given the need to review this issue, personnel from Rashpetco attended ABB’s alarm management training course and, as a result of this and recommendations from other ABB clients, commissioned ABB to undertake an ‘Alarm system heath check study’.
The health check study report detailed a list of recommendations for action, and concluded that the remedial work was urgently required because Rashpetco did not have an effective alarm system. ABB were subsequently asked to lead a project team made up of instrument, production, safety, process and DCS system engineers through a review of all the alarms generated by the control system.
The exercise focused on the experience and knowledge gained from plant operations since the start of 2001 to prioritise each alarm, verify each alarm threshold and check the control setting for each instrument. As a result a number of alarms, including a number of duplications, were either removed or re-categorised as events.
An ABB SmartLogger / SmartClient alarm monitoring tool was installed for the WDDM facility to provide ongoing analysis of the alarm and event data produced by the Data Historian. This helped ABB / Rashpetco to identify and prioritise further problems in both the base alarm load and peak alarm load.
An important project aim was to reduce the peak loading of alarms during plant trips or equipment failures and reduce alarm rates to manageable levels whilst being careful to ensure that important alarms were still visible and not hidden from the CRO’s.
One of the key performance targets of the project was to reduce the rate of alarms being presented to the Control Room Operative’s (CRO’s) down from its initial rate of 390 alarms per 10 minutes to below 3 alarms per 10 minutes. This was achieved and bettered with the alarm rate reducing to 2 alarms per 10 minute period (figure 1).
ABB were subsequently commissioned to undertake a similar project on an adjacent plant (Rosetta) as a direct result of the successful work already carried out on WDDM. The same approach and delivery mechanism were used throughout this second project which again resulted in significant alarm number reductions to below 1 per 10 minute period (figure 2). On completion of the assignment, Rashpetco accepted all of the recommendations made by ABB and have since commissioned ABB to provide alarm system specialists to work alongside their own staff to implement a programme of further remedial action as quickly as possible.