Höegh LNG and Altera Infrastructure is scaling up large scale CCS infrastructure

In a joint initiative, called “Stella Maris CCS” Altera Infrastructure and Höegh LNG are working together to provide cost efficient floating Carbon Capture and Storage infrastructure solutions for a global market, not limited to size or geographical location. Valuable infrastructure experience is brought together; with FPSO (Floating Production, Storage and Offloading) and Dynamically Positioned Shuttle Tankers from Altera and FSRU’s (Floating Storage Regasification Unit) from Höegh. We intend to continue to build on our heritage and experience, using our combined skills to contribute to carbon emission reduction around globe. With the “Stella Maris CCS” project, we will essentially be doing what we are doing today, only in reverse. Our solution, initiated in 2019 as the first of its kind, will offer a large-scale floating infrastructure for collection, transport, and injection of CO2 into subsea reservoirs/aquifers. Our infrastructure concept consists of 2-3 Carbon Collection Storage Units (CCSU) to aggregate volumes at different key locations, 3-4 CO2 Shuttle Carriers and one Floating Storage and Injection Unit, the total amount of CO2 injected with these assets can reach up to 10 million tons per year. In order to realize large scale CCS, the unit costs must come down, and the barriers for emitting industries to invest in capture plants must be lowered. With Stella Maris we are addressing these hurdles. The larger ship design enables carrying volumes of CO2 at low pressure and will allow for greater economies of scale in the absence of a pipeline which places less limitations on distance to reservoir and ultimate flow capacity. Having a centralized conditioning of CO2 in a CCSO hub allows more flexibility for on-site capture design from multiple onshore industrial emission sources with shared port access. To defray high logistics cost in e.g. the Baltic region, a hub and spoke transportation approach enables collection in smaller parcels, milk-run gathering and conditioning for large scale transfer for storage in an offshore subsea reservoir on the Norwegian Continental shelf

Research on seismic performance of new bridge pier seismic reduction isolation system based on shaking table test

In view of the current poor seismic performance of bridges, this paper started with the vibration isolation and reduction mechanism of the bearing, and deduced the coordination relationship between the stress and the deformation of the bearing under the vibration isolation and vibration reduction working conditions. Combined with the shaking table test, the defect that the traditional rubber bearing has poor seismic isolation effect was analyzed. Based on this, a base-bearing double reduction system was proposed and its vibration reduction and isolation effect was compared with the traditional bearing. The shaking table test results showed that, compared with the traditional bearing, the proposed vibration reduction system had better energy dissipation effect and could weaken the apparent cracking damage of the pier under the action of earthquake. Under the 125 m/s2-750 m/s2 peak acceleration excitation of the EI-Centro wave, the proposed vibration reduction system could greatly reduce the displacement variation of the upper main beam by 20 %-47 %. Moreover, the results of dynamic amplification factor measured at the corresponding height of the two types of piers also verified that the proposed base-bearing double vibration reduction system had greater competitiveness when the peak acceleration of seismic waves was less than 500 m/s2

Reliability calculation with error tree analysis and breakdown effect analysis for a quadcopter power distribution system

Quadcopters are playing an increasingly important role in a variety of industries due to their numerous advantages over other types of aircraft. Additionally, quadcopters are susceptible to damage, and their repair can be costly. On the other hand, today, reliability is recognized as a critical design feature in most industries. A device's reliability is one of the most important and complex issues in the field of engineering since it provides engineers with an insight into how a device performs. Due to the fact that reliability is a major factor in all industries and can significantly affect the quality and life of products, we analyzed the reliability of a quadcopter using statistical relationships, mathematical models, and previous experiences. After examining the failure modes and their effects on the system, the effects of the quadcopter failures are analyzed using the FMEA method, in order to determine the cause and mode of the failure. Finally, to determine the causes of failure, we have checked the quadcopter by the FTA method to minimize the possibility of failure. The purpose of this article is to discuss definitions and concepts in the field of reliability, followed by an analysis of the quadcopter and its components

Eigen value approach with memory dependant derivative on homogeneous isotropic infinitely extended rotating plate of a finite thickness in absence of heat source

Our present manuscript is an attempt to derive a model of generalized thermoelasticity with dual phase lag heat conduction by using the methodology of memory dependent derivative for a isotropic rotating plate subject to the prescribed boundary conditions with constant magnetic and electric intensities. Two integral transform such as Laplace transform for time variable and Fourier transform for space variable are employed to the governing equations to formulate vector-matrix differential equation which is then solved by eigenvalue approach methodology. The inversion of two integral transformations is carried out using suitable numerical techniques. Numerical computations for displacement, thermal strain and stress component, temperature distribution are evaluated and presented graphically under influences of different physical parameters

Corrosion behavior of Graphene reinforced Al-12Si coated 7075 Aluminium alloy

This paper aims at investigating the effect of graphene reinforced Al-Si coatings on the corrosion behavior of AA7075 aluminium alloy. Al - 12Si alloy powder reinforced with 0.5 and 1 wt.% graphene was plasma sprayed on AA7075 substrate. Potentiodynamic polarization measurements were performed using CHI660E-CH electrochemical workstation. It was observed that 0.5 wt.% graphene reinforced Al-Si coating enhanced the corrosion potential from –0.893 to –0.761 V and reduced the corrosion current density from 1.3×10-4 to 9.78×10-6 A/m2. The atmospheric galvanic corrosion was simulated using COMSOL Multiphysics finite element package. It was observed that AA7075 aluminium electrode potential with respect to AISI 4340 steel increased from –0.76 to –0.59 V. The least average current density of 0.95 A/m2 was observed at 95 % relative humidity and 0.0035 kg/m2 salt load density indicating the minimum corrosion rate for 0.5 wt.% graphene reinforced Al-Si coated AA7075 substrate. The simulation also confirmed that 0.5 wt.% graphene reinforcement in Al-Si coatings enhanced the corrosion behavior of AA7075 when compared with 1 wt.% graphene reinforcement

Analysis of the influence of super large area and super deep foundation pit excavation construction on surrounding subways

The shortest distance from the deep foundation pit envelope of the project to the subway station building is only 7.7 meters, and the deepest excavation depth of the foundation pit is about 24 meters. The surrounding environment of the foundation pit is complex, involving many buildings, the construction is difficult, and there is a great risk of construction safety. The effective control of the structural deformation of the existing subway station is the key to selecting the underground enclosure structure and construction process of the surrounding post-construction projects. Combined with the actual situation of the project, the three-dimensional numerical analysis method is used to analyze the impact of the construction of the foundation pit of the building on its adjacent structures in detail, and the relevant treatment measures are proposed. The research shows that the unloading effect caused by the large-scale excavation causes the soil outside the pit to move towards the inside of the pit. Under the influence of the soil deformation transfer effect, the Beiguan Station of the R1 line subway produces certain rebound, settlement and horizontal displacement, but the values of each deformation index are within the deformation control standard, the numerical analysis considering the influence of small soil strain can better reflect the influence of foundation pit excavation on the displacement, deformation and internal force of the existing structure. It can better match the actual engineering experience

The application of seismic parameters conversion among different structure design codes

The main goal for structure engineer is to do safety design and make sure structures can resist seismic forces by adopting proper construction materials and structure systems. The seismic design parameters are the key factors to control the structure seismic design procedures and results. These parameters covered several items, such as seismic spectral response acceleration in 1 second (S1) and short period (SS), site classification(A~E), sites importance (Ie,), strong motion files with their pseudo-acceleration and displacement, etc. Around these parameters, different countries and regions also issued the domestic design principles correspondence. For international projects, no matter which area or country projects located in, every structure engineer should take more care about the proper seismic parameters to deploy seismic design, and the issues of seismic parameter conversion among various codes appeared a few decades ago. In this article, author focused on multiple stories hotel (RC) structure design with GB and ASCE seismic parameters controlling, demonstrate the difference of structure design principles between GB and ASCE, and applied specified seismic parameters conversion method, then deploy structure analysis based on these parameters, got series structure analysis results. In the end, author provided a few practical advice about developing strategies and decisions from consultant view. These conclusions not only can benefit developers, also strengthen the support from consultant agency, besides, the parameter screen procedures enhanced the structure designer’s driving ability on various structures which locate in different regions and countries

Prevalence of orofacial pain and temporomandibular disorder among violin and viola players: a pilot study

Prevalence of orofacial pain and temporomandibular disorder was evaluated among violin and viola players, having as control group other string players (cello and double base players). We found a high prevalence and more severity on violin /viola players. We also found that it is not related to the number of hours performing the instruments. Violin and viola players are more prone to headache and more aware of their parafunctional behavior

Comprehensive sensitivity analysis on static and dynamic reservoir parameters impacting near wellbore injectivity during CO2 sequestration

Carbon capture and storage (CCS) is proved to be effective measure for reducing CO2 emissions. whilst the world still highly depends on the use of fossil fuel energy, this method is necessary for reaching the world’s 1.5 °C goal. In CCS, CO2 is hindered from entering the atmosphere by capturing it from sources of emission and storing it in geological formation. Saline aquifers among all possible underground formations are most common targeted ones for CO2 storage due to their frequent presence, and large storage capacity. However, this storage option suffers from sufficient well injectivity to inject large volumes of CO2 at acceptable rates through a minimum number of wells. The injectivity impairment / reinforcement happens through mineral dissolution, fine particle movement, salt precipitation and hydrate formation (known so far). Each of these mechanisms will be more dominant in injectivity alteration at different distance from the injection point depending on reservoir pressure and temperature, formation water salinity, rock mineralogy, and flow rate of CO2 injection as well as its dryness. Incorporating all the finding into radial flow near wellbore will help gaining insight into the resultant of injectivity changes over time and distant from injection point. In this study we have chosen Eclipse 300 together with an open-source code to investigate the impact of formation characteristics, CO2 -Brine-Rock interaction, pressure, temperature as well as injection rate on injectivity alteration. The goal for this work is to provide a workflow which can help predicting injectivity alteration using the existing tools. Simulation results show that the high homogenous horizontal permeability in combination with vertical flow baffles in the formation (among all other parameters) has positive impact on storage capacity by increasing residual trapping. However, permeability is affected severely by salt precipitation during CO2 injection. Combined static and dynamic parameter study demonstrate that the injection rate plays a crucial role in size and expansion of CO2 plume as well as growth rate of dry out zone length, amount of salt precipitation and length of equilibrium region. The higher the injection rate, the quicker activation of the capillary and gravity force which leads to drag more brine to near well-bore resulting in higher volume fraction of salt precipitation. However, low injection rate could result in smaller CO2 plume, shorter dry out zone and longer equilibrium region in term of distance from injection point

Study on empirical model and CFD about pressure rising in Cab during door closure

Aiming at the problem that there is a strong eardrum pressure in the passenger car during the closing process, two analysis and prediction methods, fast formula prediction and CFD simulation based on accurate models, are proposed. The regression model of ear pressure comfort was established by DOE method and multiple linear regression; The simulation software star-CCM+ is applied to simulate and analyze the dynamic characteristics of the flow field in the cockpit during the closing process by using the overlapping grid technology, and the pressure change curve near the ear is obtained. Finally, the CFD numerical simulation model is established by comparing and analyzing the regression prediction analysis results and the real vehicle test data. The results show that the effects of closing speed, effective opening area of pressure relief valve and air tightness of the whole vehicle on the pressure of passengers’ eardrums decrease in turn, and the prediction error of multiple linear regression equation is 17 %; The analysis error of the internal flow field dynamic characteristic model based on refined modeling is 8 %. This study provides a theoretical basis for solving the problem of rapid prediction of eardrum pressure and optimization of engineering structure