Crude Oil Storage Tank Refurbishment Duration Optimized by 40% Through Advanced Techniques

Crude storage tanks are an important asset in every oil company. Having adequate storage capacities is important economically and ensure steady supply of oil in the market. Hence, taking a huge tank out of service for refurbishment is technically and safety critical, and as much as putting it back into service on time. This paper presents an advanced methodology and assessment of tank refurbishment process of large capacity Crude Storage Tanks, in compliance with the International Codes and Standards resulting in optimization of the project schedule by approximately 40% as compared to conventional methodology of refurbishment. By deploying the advance techniques, detailed assessment, and dynamic planning we have been able to accelerate the completion of the project, improve tank availability time without compromising with the Integrity and HSE.

TOWARDS A DIGITAL TWIN OF A STORAGE TANK USING LASER SCAN DATA

This paper proposes a methodology to automatically extract components of an oil storage tank from terrestrial laser scanning (TLS) point clouds, and subsequently to create a three-dimensional (3D) solid model of the tank for numerical simulation. The proposed method is integrated into a smart analysis layer of a digital twin platform consisting of three main layers: (1) smart analysis, (2) data storage, and (3) visualisation and user interaction. In this proposed method, primary components of the tank were automatically extracted in a consecutive order from a shell wall to roof and floor. Voxel-based RANSAC is employed to extract voxels containing point clouds of the shell wall, while a valley-peak-valley pattern based on kernel density estimation is implemented to remove outlier points within voxels representing to the shell wall and re-extract data points within voxels adjoined to the shell wall. Moreover, octree-based region growing is employed to extract a roof and floor from remaining point clouds. An experimental showed that the proposed framework successfully extracted all primary components of the tank and created a 3D solid model of the tank automatically. Resulting point clouds of the shell wall were directly used for estimating deformation and a 3D solid model was imported into finite element analysis (FEA) software to assess the tank in terms of stress-strain. The demonstration shows that TLS point clouds can play an important role in developing the digital twin of the oil storage tank.

Tank Wall Thermal Stress Analysis and Risk Prevention and Control of Crude Oil Storage Tank

If the crude oil in storage tank is directly heated without considering its temperature distribution, several problems will occur, namely, the thermal expansion of crude oil, and the uneven thickness of the condensate layer, bringing difficulty to the safe management of crude oil storage and transport. However, few scholars have analyzed the temperature field distribution of crude oil storage tank (COST) under heating, or the internal force of COST under static force. Thus, this paper probes into the thermal stress of tank wall, and the risk prevention and control of COST. Firstly, the heat transfer properties of COST were analyzed, an energy balance model was constructed for COST, and several variables were selected to evaluate the heat transfer effect of the tank under different heating modes, including thermal design power, temperature rise rate, and heat energy utilization rate. Next, the cross-section of COST wall was selected for thermal stress analysis. Based on the extremes of circumferential and vertical thermal stresses, the weak parts of COST susceptible to risks like leakage were determined, and several measures and suggestions were presented for reducing the risks of crude oil storage and transport.

Remote Inspection of a FPSO Unit Crude Oil Tank whilst still Producing

In 2020, with the unit still producing a crude oil storage tank on the Bumi Armada owned and operated Armada Kraken FPSO was successfully inspected by Texo using a UAVS flown from outside the tank. This type of truly remote survey significantly reduces the risk to personnel, the survey time and the survey cost, whilst maintaining a survey standard that is close to that achieved by personnel entering the tank and utilising scaffolding. Lessons learnt in the following areas are discussed: • Detailed Scope of Work value, including potential & actual anomaly handling. • Careful pre-mobilisation briefing of the project team and Class surveyor. • Engagement with Bumi Armada personnel, onshore and offshore, and the Texo project team. • Engagement with DNVGL to enable the inspection to be Verification & Class credited. • Development by Texo of project specific procedures based on onshore trials. • Tank cleanliness and cleaning.