Plastic Liners for Offshore Production Lines: A Cost Effective Alternative Solution to Corrosion Resistant Alloys?

This paper presents the investigations performed by TotalEnergies and Saipem on the cost effectiveness potential of internal plastic lining for corrosion protection of offshore production lines. Objective was to better understand for a complete EPCI cost comparison the various parameters that could have a significant impact on the potential savings associated with the use of plastic lining instead of CRAs (Corrosion Resistant Alloys) for very corrosive production fluids such as sour gases. An extensive cost comparison study between CRA lining and plastic lining for offshore production lines was performed considering sensitivity on several parameters: 3 pipe diameters, S-Lay, Reel-Lay and J-Lay installation, sensitivity to external thermal insulation requirements, mechanical and design requirements, to pipe length and fixed costs (technologies and vessels). A dedicated calculation tool for system design and cost assessment was built on purpose for this sensitivity study. Costs were assessed for the various cases, starting from pipe design, then assessing procurement costs, fabrication costs then installation costs with preliminary cycle time assessment. Project management and engineering costs have been considered to obtain comparative EPCI (as installed) cost assessments for the various study cases. Plastic lining appears to be a cost-effective solution installed in J-Lay or S-Lay in addition to reeling (up to 45% of potential cost savings on installed line compared to CRA lining). The main driver for the cost savings is associated to the procurement of the pipes and associated lining, including pipe manufacturing. Some smaller savings can also be obtained from the offshore cycle times in J-Lay and S-Lay as the CRA welding add a significant operation time in comparison with standard CS welds. The fixed additional costs associated to the plastic lining (specific tooling for example) can be quickly amortized after a few kilometers thanks to the material cost savings. Integrating them as a company investment allows to unlock costs savings even for shorter lines. The thermal contribution of the plastic liner is also interesting regarding the overall pipe insulation design. This study completes the works already performed by the industry on the offshore costs of plastic lining as it considers the whole EPCI CAPEX costs from the Contractor and Operator points of view and offshore experience. The study integrates the S-Lay and J-Lay installation methods (while previous studies mainly focused on Reel-Lay) and includes an extensive sensitivity study with various key parameters such as pipe sizes, pipe design requirements, material costs and offshore operation times to get a general overview of potential benefits associated with plastic linings for offshore production lines transporting corrosive fluids such as sour gases.

Performance analysis of standalone photovoltaic power generation in different load conditions in India

The conversion of solar energy into electrical energy by the design of energy-efficient way is the key objective of this paper, which can be used as a main source of power for the main building of Polytechnic Institute to meet its daily energy requirement by replacing the all exist-ing fluorescent lighting loads to LEDs. The main purpose to choose a standalone photovoltaic system is due to the huge power cut in this location. This institute is situated in a rural area of West Bengal, India. The use of photovoltaic power relies upon assortment factors, such as structuring, topographical area, climate condition, sun-based irradiance, and burden utilization. Point by point use examinations including the two sorts of lighting burden, establishment, and upkeep of sun-based PV framework amid its life expectancy has been completed. Moreover, the analysis has two dimensions, one is cost comparison and payback calculation with respect to energy by replacement of load and another is, though the initial investment is high in a off-grid photovoltaic system, during the life span of the scheme, it not only returns this capital in-vestment but also gains substantial dividend.