Holistic Network Modelling for Debottlenecking of a Highly Integrated and Complex System for Optimizing Hydrocarbon Evacuation
Authors: Tan Frankie Kia , Kulkarni Sukrut Shridhar 
Published: March 2021

This paper deals with debottlenecking approach of complex and integrated system through means of Holistic Modeling for optimizing hydrocarbon evacuation. As prudent operator for the complex network, it is crucial to pursue strategic ideas and innovative concepts to optimize supply demand balance, fulfill contractual obligations to optimize resources to maximize value creation, whilst protecting investment decisions for monetization of the new field development. It therefore necessitates to prioritize system reliability and de-bottlenecking initiatives to implement successful business plans with appropriate timely reconfiguration at various intensities of the network. It is consequently essential to decipher the pain points by performing root cause analysis and troubleshooting to achieve optimal fit for purpose solution by gaining better understanding of network characteristic, supply distribution & operating topology.

Paper focus on a bold step change that was commenced to develop an end-to-end Holistic Network Model from well head (fields) to product delivery to scrutinize the network and propose suitable alleviation by appraising the debottleneck requirement at offshore riser collection manifold which serves as integrated facility for multiple hubs and fields. Model was validated with plant information and deployed to yield robust & realistic results. Multiple sensitivity scenarios were accomplished to analyze current riser manifold configuration limitation checks for tie-back of new field such as ullage opportunity, pressure variations, hydraulic fluxes, potential choking of low-pressure wells/fields and prospective blending specifications violations etc. Obstacles across affected manifold could be estimated and its reconfiguration was planned by means of variations in operating philosophy, alterations in the manifold assembly with appropriate manifold debottlenecking recommendation.

Analytics of Integrated Network modelling could qualify not only technical obligations but also empower representative economic evaluation for debottlenecking by appending precise requirement in terms of manifold reconfiguration, backed up by appraised data from network model. Model output also assisted to gauze the potential for enhancing network capacity by implementing appropriate reforms to optimize evacuation for new field line ups. Integrated network model developed with an aid of basic network elements can be subjected to estimate vital features for comprehensive network such as pressure and flow across the various nodes in the system. Methodology describes how by developing an integrated network model that summarize the granularity of a highly complex offshore gas network has facilitated to strategize the manifold reconfiguration and appraise debottleneck requirement besides proposing appropriate mitigation. With integrated network modeled on a single platform allows a uniform data transfer from various elements such as fields, facilities, pipelines, gas highways and terminals into the model which assist for network optimization.

The situational analysis via modeling could enable the elimination of new dedicated infrastructure for field evacuation leading to CAPEX optimization there by facilitating its optimal monetization. It reveals extensive usage of model with physical boundaries steering decision for project implementation.