InterOil Exploration and Production is a Norwegian petroleum company with operations in Peru, Colombia, Ghana and Angola. The company is traded on the Oslo Stock Exchange.
Abstract Background In addition to the other uses for macroalgae, since the 1970s, there has been interest in using macroalgae as a source of biofuels, due to the high rates of productivity and intrinsic advantages over other biofuel crops such as not requiring land use or significant freshwater input. A wide range of conversion processes exist but anaerobic digestion was one of the first demonstrated and is still a widely proposed conversion pathway. To be economically viable and scalable within Europe, the industry will need to be based on a small number of fast growing, high-yielding European macroalgae species. There is a wide body of scientific work on the conversion of seaweeds to biofuel via anaerobic digestion. Main text These studies demonstrate that the efficiency of this conversion pathway is highly variable between species, processing techniques, composition and digestor conditions. In this paper, we review this body of work specifically linking it to candidate species for European macroalgae bio-energy cultivation with the aim to promote the future development of the European macroalgal cultivation sector and allow for a better alignment with the requirements for biofuel production from macroalgae. Conclusions Overall, anaerobic digestion of seaweed offers opportunities for large-scale energy production which avoids some of the issues that have faced previous generations of biofuels, but there are a number of key challenges to overcome to ensure wider adoption and economic viability. (1) Optimising the biomass production to ensure an economic and uniform feedstock with the composition optimised to increase desirable characteristics such as sugar content and the carbon and nitrogen ratio and to reduce inhibitory factors such as halogenated secondary metabolites, sulphur and heavy metals. (2) Improving conversion rates through co-digestion, pre-treatments and tailored microbial communities, using scalable and economically feasible technology. (3) Developing tailored microbial communities capable of utilising the diverse polysaccharides in seaweed feedstock and being tolerant of the saline conditions associated with them. Addressing these issues will deliver significant benefits towards the development of a bio-energy industry based on the anaerobic digestion of cultured seaweeds.
MicroCT imaging is performed before and after confined compression testing of a minicore of Boise sandstone to extract quantitative information on the microstructural controls on compaction initiation and distribution, and to test whether grain size distributions tend to conform to a power law through comminution. In contrast with traditional compaction studies, this analysis focuses on local statistics among regions of a given sample as opposed to global statistics in a sample set. The original workflow includes a segmentation strategy and the definition of a series of metrics that are evaluated throughout the entire image volumes before and after testing. The results suggest that local porosity and sorting are the main controls on local strength, whereas neighborhoods with larger mean grain size do not appear to be more prone to yielding. Furthermore, our observations appear to confirm the tendency of grain size distributions to become self-similar through the elimination of same size neighbors at all scales, consistent with the concept of fractal compression.
Abstract The objective of this paper is to improve the new model of the non-conventional project management and specify the standardization of various type of partnership models in project delivery governance and technical assurance processes by ensure consistency when developing opportunities for hydrocarbon and non-hydrocarbon facilities (Partnership Model). This paper has investigated the following topics: Governance and Assurance requirements for projects containing partnership model. Project delivery strategy selection and process on various types of Partnership Model Availability Assurance of partnership model facilities, and production monitoring process. Outlining the most effective agreement duration for each partnership model. This development methodology will provide invaluable appraisal governance that shape and regulate various partnership models across the project phases (Identify to Operate) and ensure a robust technical functional specification requirement for each model (Figure 01-"Partnership Models Governance and Assurance Process"), extracted from Public-Private Partnership (PPP) concept. The assurance process will cover and mitigate technical, and assurance challenges associated with different partnership models on Projects not limited to the following: Payment Structure: Economics scenarios with or without financing to be considered during technical evaluation model. Buy-Back Fee: an option to establish an agreement with/without transferring the ownership of the assets from investor for various type of 3rd party, BOT projects via partnership model. Project Assurance Plan: Establishing a risk-based framework and principles that allow operating companies to be more flexible and operate efficiently. Functional Specification: Project Owners to provide robust functional specification at early stage (Select phase) of the projects. Communication Protocol: Managing interface by establishing a solid communication protocol between the client facilities and investor (BOT, DBOOM, BOOT) facilities, to guarantee the desired outputs. Standard Equipment: Equipment segmentation for different types of partnership models. Production Monitoring: Proposed metering protocol to avoid technical constraint during Operation phase. Technical/Technology Risk Assessment: De-risk the full development through early production for hydrocarbon facilities or reduction an environmental exposure via non-hydrocarbon projects. Limitation: The process investigated the limitation for each partnership model option based on existing 3rd party or BOT, DBOOM projects learnings. It’s recognized that there may be some complex scope in partnership model projects that fall under more than one segmentation category e.g. Gas to Power (GTP) projects could potentially be combined with gas processing facility sourcing strategy. This study will highlight the importance of governance and assurance processes and a hybrid PPP (3rd Party, BOT, DBOOM, IPP Projects, etc.) concept that serves projects delivery in the energy Industry. Figure 01EPC and O&M Project Delivery Quilt
Abstract The objective of this study and paper is to gain a better understanding of long term HMPE mooring rope performance for permanent facility mooring applications. The study specifically applies to HMPE rope used to moor an FPSO for a duration of 7 years. The HMPE rope was in and on the seabed, connecting the mooring line to the anchor, in this application for long term mooring. The temporary Serpentina FPSO moorings (2013 - 2019) included an HMPE mooring rope in each of the 9 mooring lines. All ~350 ft length ropes were located at and under the mudline as forerunners to a drop-embedded anchor. The mooring lines were recovered in 2019 and stored quayside in Louisiana until being cut into samples and tested for this project. The HMPE (Dyneema® SK78 fiber) mooring rope underwent the following tests: Full scale MBL testsDissection & visual / MicroCT inspectionFiber testing (comparing used fibers with new fibers, including residual creep testing (ARELIS)) All results indicate that the ropes are suitable for long term use. Two full scale rope MBL tests were performed that indicated the residual rope strength was over the rated average break strength. Inspections indicated an absence of foreign particles within the rope. Fiber testing indicated a sufficient residual creep life for continued deployment in excess of the lives of most LTM systems. No long-term deployment of HMPE fiber ropes in/on the seabed mooring a permanent facility with subsequent testing has been documented in industry to the knowledge of the authors. The results from this study indicate new potential for mooring components that are not subject to corrosion and allow for enabling anchor technologies to be used in permanent facility, offshore wind/renewables, and other mooring system applications.
We study the impact of switching from combustion heating to electric heating in processes comprising high temperature reaction/separation sequences, where the heat supporting the reaction(s) is substantially provided by combusting a reaction byproduct (fuel gas). A canonical process structure is de?ned. It is shown that the conventional combustion- based process presents signi?cant interactions. An asymptotic analysis is utilized to investigate and compare the dynamic responses of the conventional and electric process configurations. It is demonstrated that the dynamic behavior of the two processes exhibits two timescales, with the faster corresponding to the evolution of the temperatures of the units with high heat duty, and the slow time scale capturing the variables involved in the material balance. A simpli?ed ethylene cracking process example is used to demonstrate these findings.
