How to objectively quantify the level of clogging in filters used in a gas expansion station?
In a continuous improvement process, a gas distribution company wanted to have a better monitoring of filter degradation. This one would help to optimize the lifetime and to improve the intervention planning.
However, the client only had very limited information available about the filter condition. Moreover, due to the variable operating conditions, the degradation could not be assessed correctly.
To obtain this information a new approach was developed by Performance for Assets.
The customer was already using online monitoring to measure pressure drops in the filters. When the pressure reached a threshold, an alarm was triggered in the control room and an intervention request was be sent to maintenance to replace the filters.
This approach had a number of disadvantages:
To address these ones and estimate the filter degradation more precisely , P4A applied a physical approach based on the pressure drop model as a function of the flow.
The output consists in an iterative estimation of the pressure drop coefficient filtered to mitigate measurement noise and modelling errors. This approach enabled to build indicators not influenced by the operating conditions.
The resulting indicators are:
Level of Clogging: This indicator provides a view of the evolution of the filter degradation independently from fluctuating operating conditions.
Flow Capacity: This second indicator expressed the residual capacity of the filter in terms of flow based on its degradation status (the pressure drop coefficient).
Thanks to the solution that was developed by Performance for Assets, the end user now has a clear view of the filter condition by visualizing the current flow and capacity.