1. Amine Swap Out Study (Alernate solvent suitability to Flexsorb)
The study was awarded to recommend an alternative solvent for one of the North sea platform’s existing Acid Gas Removal (AGR) System and further optimise its operation. The platform’s current solvent Flexsorb had severe sourcing issues and resulted in production loss as amine make up was not possible to maintain the amine strenght. Elixir’s process engineering team simulated the AGR system with different solvents, using BR&E’s ProMax software. Modelling and simulation (rating) through ProMax was carried out to validate the usability of ‘Dow Ucarsol 804AP MDEA’ to meet the intended objectives of achieving the sales gas specification through solvent swap. High level review of other available solvents suitability was reviewed to check other better options. At the end of the study, we had succeeded in recommending a solvent that could achieve required export specifications while contributing to a significant reduction in the required reboiler heat duty. The client greatly appreciated our work and awarded us the next phase of the project, performing detailed adequacy checks for the installed system to facilitate a smooth transition to the new solvent.
2. Adequacy Check for new selected solvent as a part of Amine swap out study for North Sea platform.
Following up on the success of our Amine Swap Out Study recommending an alternative solvent, Elixir Consultants undertook a study of the AGR system to verify its adequacy for the optimised conditions and the new solvent. We carried out detailed hydraulic checks on control valves, pumps, and shell-and-tube heat exchangers, and we facilitated vendor reviews of specialised equipment such as plate heat exchangers and columns. Furthermore, to assuage concerns with export gas quality during start-up (high H2S in the reservoir fluid stream due to no diltion from gas lift), we performed dynamic simulations modelling the gas production and gas lift systems, estimating the time required to meet specification. Together, these checks and studies focused on identifying and resolving potential problems that could arise from the solvent swapout, giving our client confidence that the swap could be successfully executed without major modifications to the AGR system.
3. Assessment of AGR bypass (Impact on material suitability) for North Sea platform.
As the platform is predicted to soon become gas deficient, resulting in no gas export, the export gas specifications will not have to be met. Hence, it was proposed to explore the potential of bypassing the AGR system on . Fuel gas and crude oil quality would instead be managed with H2S scavenger injection, reducing the operating cost of the platform. This screening study was conducted to verify that the existing materials of the currently installed equipment and piping is suitable for the higher CO2 and H2S predicted to occur post AGR bypass. This report also evaluates the option to use H2S scavenger injection to treat fuel gas for use as a fuel gas.
4. Review of amine losses at one of the North Sea operator platform
Elixir Consultants UK Ltd was requested to get the Amine Experts view on amine losses followed by north sea platform visit to support Operations team to identify the root cause of amine loss. Elixir team carried out the Process Simulations to confirm the theoretical amine loss with reference to the current operating conditions and came to conclusion of valve passing leading to amine routing to the closed drain/LP Flare KO Drum. During site visit the potential valve passing was identified and crossverified. The recommendations were made to replace passing valves and provding DBB valves whereever found necessary.
5. FLOW ASSURANCE
5.1. Flow Assurance / FEA work (Phase 1 and Phase 2)
The gas lifted well (converted from water injection well) flowline failure (causing damage to support, pipework and loss of production) analysis was investigated by Elixir. Under investigation the Line sizing and FIV screening was carried out for the current process data. This has been carried out for various operating and startup cases. The outcome from this study has highlighted that there are excessive load forces occurring during start-up cases which are in excess of the current piping/stress design (Cases 4A/4B/4C). Since these calculations are based on static calculation methods, as part of this study it was recommended that for these start-up design cases, flow assurance modelling is to be carried out to ascertain more realistic results for the forces.The model was prepared using appropriate elements, and time-dependent pressure fluctuations from flow assurance data was applied to the internal pipe surfaces for analysis.
5.2. DP6 DP8 Pipeline Transient Analysis for Spirit Energy
During well cycling operation (closing and opening of DP6 or DP8 pipeline) there was a possibility of sudden gas in-rush (due to higher DP across Riser ESDV with lower topside operating pressure) causing higher velocity liquid slugs, which might cause pipework/ intrusive device vibrational issues. The study scope was to eview the impact of riser ESDV opening with various downstream pressure.The OLGA transient analysis was carried out to check possibility of liquid slug and mixture velocity to analyze the momentum values.
5.3. FG Import -Low Temperature study (Riser ESDV opening) for Spirit Energy
The scope of the study was to review the impact of riser ESDV opening and possible low temperature issues using OLGA transient simulation.Although OLGA simulation showed fluid temperatures attaining lower temperature than design temperature, however it could not sustain for longer duration to attain metal temperature lower than design temperature. Recommended to open Riser ESDV but with caution of downstream piping support checks for high momentum.
5.4. Minimum Temp Analysis for FG Import Scrubber during platform startup for Spirit Energy
The high-pressure FG import gas routed to FG Import Scrubber via Pressure Reducing Control valve leading to lower operating temperatures in FG Scrubber than design during platform startup. The scope of the study was to review the possibility of low temperatures in FG Scrubber during platform startup. The OLGA transient analysis (using isoenthalpic curve) was carried out to check the possibility of low temperature in the FG Scrubber and recommended pressurization of FG Scrubber before opening PCV upstream of Scrubber.
5.5. N16, N7 & BK8 Flowline/Pipeline settle out pressure calculations for Apache
The opening of flowline PCV with higher settle out high-pressure exceeds the separator PSV capacity, therefore it was decided to review the pipeline settle out conditions for various flows and topside pressure using OLGA simulation.The settle pressure prediction curves were established using OLGA for various topside pressure conditions alongwith various flows.
5.6. Flyndre Sand Flow Assurance Study
The scope included-Evaluate current flow regime to determine fluid phase velocities-Perform erosional velocity evaluation in accordance with DNVGL-RP-O501 Managing Sand Production and Erosion-Perform sand deposition modelling including model sensitivities to evaluate sand deposition boundaries under historic, current and future flow profiles.
6. BRODICK Concept Phase Flow Assurance Report for North Sea client in UK
The scope of this work was as follows:
• Using details of the well trajectory, fluid and reservoir properties (pressure, temperature,well PI), estimate the expected WHFT/P over a range of water cuts and lift gas contributions(to feasibility level).
• Develop a pressure-flow relationship for each of two prospective tie-in points. Establish whether aspirational production profile rates are feasible with 6-inch and 8-inch flowlines.
• Conduct erosion estimate based on nominal sand-free fluids, to confirm line size.
• Produce temperature and pressure profiles to aid in understanding as to whether a cooling spool will be needed or not.
• Confirm line sizing for the following ancillary lines:o Gas lifto Methanolo Scale Inhibitor.
• Assess expected thermal and hydraulic behaviour on turn-down and on un-planned shutdown.
7. Leman 27BC (compression platform) Firewater hydraulic study for Perenco
The scope of the study for Phase 1 was to update the previously completed steady-state Hydraulic Analysis with the latest changes to the firewater system.a. New helideck monitors nozzles,b. Slug catcher foam spray System in its new configuration (new nozzles and orifice plate).c. A New foam spray system around the pump area (Condensate Pump Area).As part of Phase 2 the transient hydraulic analysis was carried out to checka. Potential issues with pressure surge, water hammer, extraction of simple and complex force data at predefined locations,b. Confirm adequate set points for pressure switches,c. Propose potential remedial for the issues identified.
8. Dynamic Simulation Study of E-1570 for temperature excursion due to delayed TCV-1570 closure for Px
TCV-1570 closure Delay introduced to avoid pressure surge was causing temp excursion.As part of scope the steady state and HYSYS dynamic modelling was done for variuos cases:-Cases were run to find out effect of maximum acceptable metal temperatures on PST time (PST times for different temperature)-Finding out effect of ambient temperatures on startup time (Different pipe insulations were detailed in model for getting rigorous results) -Finding out temperature excursion during start up after hot shutdown -Three different cases were run to check if temperature excursion occurs at different flow rateModifications were recommended on start-up procedure based on dynamic simulation results.
9. CFD Analysis for Turbine vent stack of ACE BP platform, Azerbaijan
CFD Analysis is carried out to check the thermal plumes and comustion byproducts of turbine vent stack impacting the nearby equipment, personal access location and helideck.
10. DSEAR Assessment for NPL Gas Delivery SubSystem
Scope covers ATEX Assessment for Gas Delivery Sub-system as per the requirement of Dangerous Substances and Explosive Atmospheres Regulations (DSEAR HSE UK) for National Physical Laboratories CageCapture Experimental Rig Project, UK-To identify the leak sources inside the cabinet followed by DSEAR / ATEX assessment for gas delivery sub-system -To Confirm ATEX exclusion zone distance.
11. Dynamic Simulation study for compressor operation with eductor system.
The dynamic modeling was carried out to check the intraction between eductor system and compressor control system to ensure the compressor operates in safe operating envelope in various scenarios of operation.
Transient Analysis for Fire Water network of Perenco UK
The firewater network transient analysis study carried out for Perenco UK.
5.1. Multidisciplinary engineering deliverables covering piping, instrumentation, structural, and flow assurance scopes. Additionally conducted an N₂ dispersion study for Shell Gannet DGS to ensure safety and compliance.
Provided multidisciplinary engineering support across flow assurance, piping, instrumentation, and structural scopes. Delivered Flow Assurance Reports (Hydraulics) and OLGA Slugging Analysis, developed construct and destruct as-built isometric drawings, and prepared instrumentation drawings for Catalytic Point Gas Detectors (Workpacks 8 & 10). Executed structural modification designs including local deck plating replacement and replacement of corroded pipe supports. Produced detailed piping drawings, civil/structural support designs, and load data preparation for RSRSUK, Claymore, Armada, and Lomond assets across pre-TAR and TAR packages. Supported detailed design for oil export pump outages, gas cooler replacements, booster cooler cleaning, and seal ring replacement activities.
List of Various small projects :
- North Everest Late Life Compression Project - Piping Drawings, Civil Support Drawings & Load data Preparation
- N2 & O2 Rich vent Dispersion Study for one of the UK North sea client
- As Building of Catalytic Point Gas Detectors Workpack 8 and 10- Instrumentation Drawings
- List ItemReplace Local Deck Plating- Structural Modification scope
- Piping-0002 (pre-TAR)- Piping Drawings, Civil Support Drawings & Load data Preparation
- Piping-0003 (pre-TAR)- Piping Drawings, Civil Support Drawings & Load data Preparation
- Claymore EMD Radiator- Piping Drawings, Civil Support Drawings & Load data Preparation
- CA1682 Claymore Oil Export Modifications (TAR)- Piping Drawings, Civil Support Drawings & Load data Preparation
- Replacement of Corroded Pipe Supports
- Armada Booster Cooler Clean- Piping Drawings, Civil Support Drawings & Load data Preparation
- Lomond H-0390 Export Gas Cooler Replacement - Piping Drawings, Civil Support Drawings & Load data Preparation
- Armada Destec Seal ring Replacement NWS & Maria - Piping Drawings, Civil Support Drawings & Load data Preparation
- Lomond EPM Seals and Fuel Gas Supply - Piping Drawings, Civil Support Drawings & Load data Preparation
- Design Drawings to Support SIC Planning Application for one of the North Sea Client.