Slip Stream Research Articles

Industrial SMB chromatography as an alternative to the conventional refining of raw cane sugar

Simulated moving bed (SMB) chromatography is a well-established and widespread unit operation in the beet sugar industry and has been practiced commercially for more than thirty years. SMB chromatography has proven to be very efficient at removing inorganic ash components and colorants from sugar liquors, particularly those colorants with relatively high molecular masses. Recent optimization of the separation using raw sugar with a color ranging from 2000 IU up to 4000 IU has focused on minimizing the capital and operating costs of a chromatography system to replace the various purification and decolorization steps in conventional raw cane sugar refining. Decolorization levels exceeding 89% have been reliably achieved in the extract fraction from chromatography, along with ash removals ranging from 92% to 97%. As only water is added to purify the sugar, the application of this technology, in combination with modern industrial heat pumps and mechanical vapor recompression, allows for a powerful CO2-neutral process, with all the associated benefits regarding permits and marketability. The potential of this technology includes integration into new refinery projects (either standalone or back-end) by replacing affination, carbonatation and ion exchange decolorization (with raw sugar colors of up to 5000 IU), to expansion of existing refinery sites for slip stream processing of raw sugar syrups or refinery run-off syrups after clarification, and to the introduction of new process steps, such as direct liquid sugar production from cane raw sugar.

Investigation of Asymmetric Twin-Rudder Load Behaviour Through Free-Running Model Tests

Abstract During tight manoeuvres, twin-screw ships equipped with two rudders located in the propeller slip stream experience a fairly large imbalance in the hydrodynamic loads on the propeller and rudders. To investigate the phenomenon of rudder asymmetric load in some depth, manoeuvring experiments based on a free-running model were set up in which the kinematics of the model, the forces on the rudder and the stock moment were recorded. In parallel, with the aim of obtaining an exact estimation of free-stream characteristics of the rudder blade, corresponding wind tunnel experiments were also performed. Based on the results of this investigation, an analysis of the interaction effects within the hull-propeller-rudder system was performed and some conclusions were drawn.

Characteristics of DAC operation within integrated PtG concepts

Including direct air capture technologies (DAC) in power-to-gas (PtG) approaches offers the opportunity to close the carbon cycle by producing methane on a renewable, carbon neutral basis, while balancing fluctuations associated with an energy supply based on renewable sources. In this respect, various synergies can arise within the integrated process structure, resulting in a strong coupling of process unit operation points. Being both, carbon source and main heat sink within the system, the influence of the DAC unit on the entire process is investigated by detailed simulation and pinch analysis. Strong dependency of overall material and energy balances on DAC operation point is revealed. Slip streams of air in this unit are found to result in an increased catalyst requirement of methanation reaction by more than a factor of six, while minor decline (18%) of catalyst demand with decreasing DAC desorption temperature is observed. Use of electrolysis as heat source for DAC seems not beneficial. Overall, severe influence of DAC operation on integrated process design for autothermal production of methane based on carbon dioxide and water captured from ambient air is confirmed.

Recent Cryogenic Carbon Capture™ Field Test Results

Sustainable Energy Solutions (SES) has been developing Cryogenic Carbon Capture™ (CCC) since 2008. In that time, two processes have been developed, the External Cooling Loop and Compressed Flue Gas CCC processes (CCC-ECL and CCC-CFG, respectively). The CCC-ECL process cools the flue gas with an external refrigerant loop. This process currently captures up to 1 tonne of CO2 per day (TPD). SES has tested CCC-ECL on real flue gas slip streams from subbituminous coal, bituminous coal, biomass, natural gas, shredded tires, and municipal waste fuels at field sites that include utility power stations, heating plants, cement kilns, and pilot-scale research reactors. The CO2 concentrations from these tests ranged from 5 to 22% on a dry basis. CO2 capture ranged from 95-99+% during these tests. Several other condensable species were also captured including NO2, SO2 and PMxx at 95+%. NO was also captured at a modest rate. The CCC-CFG process has been scaled up to a 0.25 ton per day system. This system has been tested on real flue gas streams including subbituminous coal, bituminous coal, and natural gas at field sites that include utility power stations, heating plants, and pilot-scale research reactors. CO2 concentrations for these tests ranged from 5 to 15% on a dry basis. CO2 capture ranged from 95-99+% during these tests. Several other condensable species were also captured including NO2, SO2, and PMxx at 95+%. NO was also captured at 90+%. Hg capture was also verified and the resulting effluent from CCC-CFG was below a 1ppt concentration. This paper will focus on discussion of the capabilities of CCC generally, the results of CCC-ECL field testing, and future steps surrounding the development of this technology. Test results that will be presented have been collected during 9 months of testing at a commercial power plant under funding from the US Department of Energy (DOE) and the host utility. Testing of one of the systems at a commercial cement plant in the United States will also be discussed. During this testing, the system captured CO2 from the cement plant and stored the CO2 in pressurized tanks. These tanks were provided to a partner company that later used the CO2 in a CO2 utilization demonstration. The CO2 was utilized to cure concrete manufactured using cement from the same plant where the CO2 was captured. This integrated capture and utilization demonstration was the first time that the cement industry has shown in the field that it can sequester its CO2 emissions in its main product stream. This represents a potential game changing solution for industrial CO2 emissions. Operational data and host-site feedback indicate that the CCC process is ideally suited for deployment into a variety of commercial environments. A few areas of de-risking remain to make sure the technology can meet very strict industrial reliability standards. These areas of de-risking are identified and discussed. The product CO2 is shown to meet specification for many uses including industrial and merchant applications. The technology is nearing readiness for deployment at commercial scale and several initial target markets have been identified.

Drag and Heat Transfer Effects on Hypersonic Vehicles in Close-Proximity Flight

A computational investigation of the drag and heat transfer experienced by multiple trailing (following) vehicles in hypersonic flight is presented. Linear arrays of vehicles in flight at Mach 10 are modeled. Results are presented for both parametric two-dimensional cases and for a three-dimensional case. Drag and heat transfer on trailing vehicles in two-dimensional (five vehicle) arrays, for both powered and unpowered configurations, are shown to reduce progressively from leading vehicle to trailing vehicle such that trailing vehicles can experience less than 30% of the drag and heat transfer experienced by the lead vehicle. The three-dimensional study examines pressure drag effects for generic lifting body/wave-rider configurations in a three vehicle array. Drag due to pressure on the trailing vehicle in such an array falls to approximately 20% of that experienced by the lead vehicle for an unpowered case and to less than 20% for the powered case. The drag and heat transfer reductions are due to the developing slip stream resulting from the successive vehicles, with attendant and progressively increasing reductions in local approach Mach numbers, local approach velocities, and surface pressures experienced by trailing vehicles.

Three-dimensional reconstruction of a microjet with a Mach disk by Mach–Zehnder interferometers

The Mach–Zehnder interferometer with the finite fringe method is applied for the first time to diagnose the three-dimensional density field of a shock-containing microjet issued from a convergent nozzle with an inner diameter of 1 mm at the exit. Experiments are performed at a nozzle pressure ratio of 4.0 to produce an underexpanded free jet with a Mach disk in the first shock-cell where the Reynolds number, based upon the diameter and flow properties at the nozzle exit, is . Interferogram analyses for reconstructing the jet density fields are performed using the Abel inversion method, in which the analysis of the phase shift of the deformed fringe relative to the background fringe is carried out by the Fourier transform method. In addition to experiments, the flow field of the shock-containing microjet is simulated by solving the Reynolds-averaged Navier–Stokes equations with the SST – turbulence model for a quantitative mutual comparison between the simulation and the experiment. The detailed variation of the density field associated with the Mach disk, the slip streams and the outer shear layers near the jet boundaries are successfully captured. Furthermore, the density profile along the jet centreline obtained by the present experiment is quantitatively compared with those from prior quantitative visualization studies, such as rainbow schlieren deflectometry, background oriented schlieren, moire schlieren and Mach–Zehnder interferometer. The three-dimensional contour map coloured by the magnitude of the density gradient vector inside the microjet reveals the flow topology of the near-field shock systems and elucidates the spatial variation of the shock strength.

The Improvement of the Powering Performance on the Japan Bulk Carrier (JBC) using Rudder Thrust Fin as a Post-Swirl Stator

Post Swirl Stator (PSS), also known as the 'Energy Saving Device (ESD) Behind the Propeller' operates within the slip stream of the propeller. The aim of this project is to investigate the powering performance of a JAPAN Bulk Carrier (JBC) upon the installation of PSS. The prediction of resistance and propulsive factors were conducted using CFD simulation using SHIPFLOW CFD code. In order to find the optimised design of the ESD, three parameters were laid out and studied. The parameters are the left side fin length, right side fin length and the orientation of the fins.The aim of this study are to improvise the thrust fin design by changing the parameters to get the optimum powering performance result, and to quantify the powering performance of the JBC upon the installation of PSS in model and full scale. There were 27 different post-swirl stator configurations. All the 27 different configurations were compared in terms of its performance in model and full scale. All the 27 different configurations were simulated using full RANSE. The free surface of the water were modelled using panel method. A grid dependence study was conducted to determine the best grid cell resolution and it was chosen at a total of 7 millions cells. The bare hull resistance of the JBC were validated with available published experiment results. All the thrust fins were modelled using appendage setting in SHIPFLOW. The best thrust fins design were selected in judging its minimum drag, minimum thrust deduction fraction, minimum wake fraction, and the delivered power. It was found that he thrust fins design for case study #20 by CFD is the most optimised configuration in terms of its performance criteria as mentioned earlier. The thrust fins design was able to reduce delivered power to 6.012%. Thrust deduction was also reduced to 2.927%. Total efficiency was increased to 6.709%

Numerical analysis of in-flight freezing droplets: Application to novel particle engineering technology

The freezing of a stream of free-falling monodispersed droplets was simulated through the development of numerical models in this work. Prediction of the freezing time and temperature transition of a single droplet is beneficial for optimisation of novel continuous spray freeze drying (cSFD) processes. Estimations of the vertical free-falling distance of the droplets in a slip stream and predictions of the chances of droplet coalescence greatly enhance process understanding and can be leveraged to direct equipment design and process development. A design space of droplet diameters in the range from 100 μm to 400 μm and ambient temperatures from −120 °C to −40 °C was explored. The rate of supercooling within the design space was predicted to range from 48 to 830 °C s−1 depending on the ambient temperature and droplet size. A comparison of the vertical free-falling distances of solitary droplets and streams of droplets at different temperatures showed that the terminal velocity of a vertically falling stream of droplets is always in excess of the terminal velocity of a solitary droplet of the same size. A difference of 1.35 m was predicted for the free-falling distance of a 400 μm droplet compared to a stream of droplets at −42 °C. A comparison between flow rates for consecutively generated 100 μm droplets showed that droplet coalescence was predicted at 0.05 Lh−1, whilst at 0.02 Lh−1 a separation distance of 23 μm was maintained thus preventing coalescence.

Experimental Studies on a Mesoscale Cycloidal Rotor in Hover

This paper details the performance and flowfield measurements on a mesoscale cycloidal rotor (rotor radius of 1 in.), which operates at ultralow Reynolds numbers () and uses a design different from previous cycloidal rotor studies. The mesoscale rotor uses a cantilevered blade with a flat-plate airfoil and low-aspect-ratio elliptical blade planform. A three-component balance was developed to measure the vertical and sideward thrust, torque, and rotation frequency as the number of blades, pitch amplitude, and blade aspect ratio were varied. The studies showed that the highest efficiency was achieved with higher number of blades (4–6), high pitch amplitude (40–45 deg), and moderate aspect ratios. Phase-locked flowfield measurements were conducted using a particle image velocimetry (PIV) technique in two different orientations: chordwise and spanwise. PIV measurements show that the flowfield on the present mesoscale cycloidal rotor is highly three-dimensional and unsteady, characterized by the growth and shedding of leading-edge vortices and a trailing-edge vortex sheet similar to that seen on flapping wings; strong root and tip vortices that interact with each other to create an undulating wake; skewed inflow; and the strong interaction of the slip stream from the upper blade on the lower blade.

Separation of Mill Scale from Flume Wastewater Using a Dynamic Separator Toward Zero Wastes in the Steel Hot-Rolling Process

Along with the production of hot-rolled steel, a large amount of mixture of mill scale, water, and oil is constantly generated. It is of great importance to thoroughly separate these components from one another to make them recyclable. In the current research work, an industrial trial was carried out at an ArcelorMittal hot-rolling mill for producing clean mill scale with negligible oil by separating the mill scale from flume wastewater using a dynamic separator. A slip stream of wastewater was continuously pumped from a roughing mill flume into a tangentially motivated dynamic separator. The mill scale particles settled to the bottom of the separator and continuously moved with the water into a classifier, where the mill scale was removed and dewatered. Results of the trial show that compared to the conventional practice of sedimentation and reclamation of the mill scale in the pits, using the new method, the mill scale is more than five times cleaner with negligible oil, and the effluent water is more than three times cleaner with much less total suspended solids. As a result, after separation with the new method, the mill scale and the wastewater are more recyclable. In addition, the new technology can also lead to recovery of more waste oil and significant reduction of oily mill scale sludge.

Simulation of an SO 2 Tolerant Amine Based Post-combustion CO 2 Capture Process

Removal of multiple contaminants from flue gas streams in a single process step offers the potential to lower the cost of emissions reduction technologies. An example is the CS-Cap process, developed by CSIRO, which removes both the SO2 and CO2 from combustion flue gases. In order to further develop this process, a rate based simulation is required of not only the CO2 capture section, but also the absorption of SO2 into aqueous amine absorbents. ProTreat® simulation software was used to simulate CSIRO’s Loy Yang CO2 capture pilot plant. This pilot plant has previously been used for proof-of-concept operation of the CS-Cap process. The model simulates various scenarios and flue gas conditions to determine the effect on the operating requirements of the SO2 capture stage. It reveals that the recirculating absorbent flow rates required in the SO2 capture loop are of similar magnitude to those required in the CO2 capture stage. Manipulating the operating parameters of the SO2 capture section will affect the properties, particularly sulfate concentration, of the slip stream sent for disposal/treatment. This could potentially allow the properties of the waste stream to be tailored for the particular downstream treatment used. In addition, condensation of water from the inlet flue gas stream is identified as an issue requiring further investigation.

Control of triple-shock configurations in high-speed flows over a cylindrically blunted plate in gases for different Mach numbers

In this article, triple-shock configurations in the problem of the influence of an energy source on a supersonic flow past a plate blunted by a cylinder are studied. The changes of angles in triple-shock configurations depending on an external energy source for different gas mixtures have been investigated for freestream Mach numbers from 3 to 4.2. The dependences of angles in triple-type configurations on the characteristics of energy release have been presented. Complicated shock-vortex structures with multiple reflections of simple waves accompanying these configurations have been obtained. Generation of the Richtmyer–Meshkov instability has been established and mechanism for its generation has been suggested. Conclusion about the possibility of the control of unsteady triple-type shock configurations and accompanying slip streams with the use of an external energy source has been made.

For the Success of Oncolytic Viruses: Single Cycle Cures or Repeat Treatments? (One Cycle Should Be Enough).

For the Success of Oncolytic Viruses: Single Cycle Cures or Repeat Treatments? (One Cycle Should Be Enough).

A study of the asymmetric shock reflection configurations in steady flows

In this paper the asymmetric shock reflection configurations in two-dimensional steady flows have been studied theoretically. For an overall Mach reflection, it is found that the horizontal distance between both triple points in the Mach stem is related to the angles of two slip streams. Based on the features of the converging stream tube, several assumptions are put forward to perform better the wave configurations near the slip streams. Therefore, we present an analytical model here to describe the asymmetric overall Mach reflection configurations which agrees well with the computational and experimental results.

Electrochemical Upgrading of Bio-Oil

Bio-oil produced by fast pyrolysis of biomass is a potential source of low carbon, renewable hydrocarbon fuel. However, the properties such as low heating value, incomplete volatility, acidity, instability, and incompatibility with standard petroleum fuels significantly restrict its use as fuel. The undesirable properties of pyrolysis oil result from its chemical composition that mostly consists of different classes of oxygenated organic compounds. The elimination of oxygen is thus necessary to transform bio-oil into a liquid fuel that would be broadly accepted and economically attractive. Hydrodeoxygenation (HDO) or hydrotreating involves high-temperature, high-pressure processing in the presence of hydrogen and catalyst to remove oxygen. HDO suffers from significant challenges such as coking, deactivation of HDO catalysts by the presence of water in the pyrolysis oil, requirement of significant quantities of hydrogen to remove oxygen, and economic availability of hydrogen at a scale suitable for distributed biomass conversion. An alternative economically feasible, less hydrogen dependent and decentralized process is required to convert bio-oil to refinery ready hydrocarbons. A process of deoxygenation of bio-oil using solid-state, oxygen conductor based electrochemical cell is under investigation. The cell is operated at 500 – 550 °C to match the typical pyrolysis temperature for both physical and process integration of the two operations. The electrolysis process removes oxygen from the oxygenated organic molecule as well from steam to produce hydrogen in-situ. Thus, relatively small quantities of external hydrogen may be needed for deoxygenation, allowing for a distributed, small scale integrated upgrading unit. Mixtures of model compounds were tested using button cells and short stacks. The product from the electrochemical cell contained a suite of compounds with significantly lower oxygen content. Integrated testing of short stacks at the Pacific Northwest National Laboratory using a slip stream from a pyrolyzer shows that the product composition is similar to catalytic pyrolysis process. Additional tests are planned using improved electrode materials. Acknowledgment: This material is based upon work supported by the Department of Energy under Award Number DE-EE0006288.

An Update on the Development of the CSIRO's CS-Cap Combined CO2 and SO2 Capture Process

The successful implementation of the leading technology for post combustion capture (PCC) of carbon dioxide (CO2), i.e. absorption/desorption using alkanolamines, still faces several challenges. For countries like Australia, that do not have flue gas desulfurization (FGD) installed at coal-fired power stations, removal of acid gases stronger than CO2 (e.g. SOx) prior to PCC becomes a costly affair, particularly when emissions of these gases can be as high as 500-600ppm from brown coal power stations, compared to the desired limit of < 10ppm. To avoid the requirement of separate FGD units, the CSIRO has developed a combined capture process, called CS-Cap, which uses a single absorbing liquid to simultaneously capture SO2 and CO2 from coal-fired power station flue gas.Proof of concept has been completed at the CSIRO Loy Yang CO2 capture pilot plant in Victoria, Australia, where a CO2 loaded amine absorbent was used to remove SO2 from a slip stream of the power station flue gas. This resulted in the generation of a SO2 loaded amine absorbent which has since been used in subsequent evaluation of potential absorbent regeneration methods.

Electrochemical Upgrading of Bio-Oil

Bio-oil produced by fast pyrolysis of biomass is a potential source of low carbon, renewable hydrocarbon fuel. However, the properties such as low heating value, incomplete volatility, acidity, instability, and incompatibility with standard fuels restrict its use. The undesirable properties of pyrolysis oil result from its chemical composition that mostly consists of different classes of oxygenated organic compounds. Current process of Hydrodeoxygenation to remove oxygen involves high-temperature, high-pressure processing in the presence of hydrogen and catalyst. An alternative process of deoxygenation of bio-oil using solid-state, oxygen conductor based electrochemical cell is under investigation. The electrolysis process removes oxygen from the oxygenated organic molecule as well from steam to produce hydrogen in-situ allowing for a distributed, small scale integrated upgrading unit. Mixtures of model compounds and a slip stream of pyrolysis vapor were tested. The results show the potential for integrating a pyrolyzer and an electrochemical device for stabilizing pyrolysis oil.

Secure Persuasive Business Models and Business Model Innovation in a World of 5G

How will a promising world of 5G influence business model innovation and what are the strings attached? The development and innovation of business models in a world of 5G is an under-researched field. In the ‘slip stream’ of new technologies, which are about to be developed, it becomes more and more important to understand how business models embedded with persuasive technologies—persuasive business models—are going to be innovated and operated. The development of persuasive technologies will lead to the exponential increase of persuasive business models in the global market. This paper will focus on how to overcome security concerns linked to persuasive business models. On behalf of the inputs from SW2010–SW2016 (Strategic Workshops held by the Centre for Tele-infrastructure, Aalborg University), lab experiments in the MBIT (Multi Business Model Innovation and Technology Research Group, Aarhus University) and Stanford Peace Innovation Lab Denmark, together with state of the art persuasive business model and technology research, we give a conceptual outlook on what to expect from persuasive business models and persuasive business model innovation in a future world of 5G.

Life cycle cost analysis of MEG regeneration process incorporating a modified slip stream concept

This study proposes a modified concept for mono ethylene glycol (MEG) regeneration process to prevent the precipitation of monovalent salt (NaCl) and to economize on efficient energy use with operational flexibility. Two-stage distillation was that the second distillation column was operated after the removal of the monovalent salt while controlling the performance of the first distillation column. This modified concept was evaluated according to (i) the possibility of salt precipitation in the re-boiler of the column at various salinity in the produced water (35–224g/L) and (ii) the economic feasibility compared to a conventional concept where water is evaporated off using a single stage distillation column. The salt precipitation was investigated using the ENRTL-RK property in ASPEN PLUS. The conventional concept showed a high risk of NaCl precipitation in the column when the feed stream contains a high salinity. The modified concept showed few precipitation in the column with a high salinity in feed stream. Then, ASPEN PLUS economic analyzer were used to construct the economic evaluation according to the Life Cycle Cost (LCC) methodology including CAPEX and OPEX. The modified concept showed 9.8% decrease in CPAEX and 8.6% decrease in OPEX compared to the conventional concept. The sensitivity analysis showed that the inlet flow rate and the concentration of rich MEG were the most significant factors that affected the economic viability of the MEG regeneration process, and the modified concept was less sensitive to the inlet condition change than the conventional concept.

スリップ・ストリームのパラドックス(ワンポイント)

スリップ・ストリームのパラドックス(ワンポイント)