Bench-scale Demonstration Research Articles

CO2-responsive surfactants for greener extraction of heavy oil: A bench-scale demonstration

In water-based oil sands extraction, the recovery of ultra-heavy oil is determined by two essential stages: liberation and aeration. However, these two stages prefer opposite water-bitumen interfacial tension conditions, limiting the overall bitumen recovery. Utilizing their switchable properties, CO2-responsive surfactants were demonstrated in this study to enhance bitumen recovery in oil sands extraction. Tuning the interfacial tension in each stage improved significantly both bitumen liberation and aeration. As a result, using CO2-responsive surfactants in bench-scale extraction tests at ambient temperature improved bitumen recovery from a mid-grade Canadian oil sands ore from 15.0% to 50.4%. Moreover, the use of CO2-responsive surfactants also produced cleaner bituminous froths, which is beneficial to downstream processing of froth. The energy consumption during bitumen recovery was estimated to reduce dramatically by at least 156.1 TJ per day, attributed to the elimination of heating the processing water as practiced in the current commercial operations. In general, this study demonstrated not only the feasibility and advantages of using CO2-responsive surfactants in oil sands extraction at a bench-scale level, but also a new avenue to develop cleaner and greener techniques for heavy oil industry.

Bench-scale demonstration of thermochemical energy storage using the Magnesium-Manganese-Oxide redox system

Low-cost, large-scale energy storage for 10 to 100 h is a key enabler for transitioning to a carbon neutral power grid dominated by intermittent renewable generation via wind and solar energy. High temperature thermochemical Magnesium-Manganese-Oxide (Mg-Mn-O) redox storage in conjunction with gas turbine generators has been identified as a promising candidate for grid-scale storage applications. The excellent redox cyclability of Mg-Mn-O has been demonstrated in earlier work using thermogravimetric analysis (TGA) and tube furnace experiments.However, in order to implement this storage technology at scale, a range of technical challenges associated with containing the 1500 °C storage medium under turbine inlet pressures (4-20 bar) have to be overcome. The current paper, for the first time demonstrates the technical feasibility of Mg-Mn-O redox thermochemical storage in an internally heated and insulated pressure vessel configuration that closely approximates a realistic engineering implementation of a redox storage module and only uses pressurized air for oxidation and suction for oxygen removal during reduction. We have constructed and tested a 1 kW/0.1 kWh bench-scale storage prototype. It consists of a cylindrical 20 bar steel pressure vessel internally insulated with open-pore high-temperature alumina. A packed bed of Mg-Mn-O pellets with an embedded Molybdenum Disilicide heater is located at the center of the storage unit. The system is charged electrically by resistive heating of the bed to 1500 °C at absolute pressures around 0.1 bar, driving the endothermic thermal reduction of Mg-Mn-O. Energy is recovered by oxidation when passing pressurized air through the porous reactive bed. The energy released heats up the air, which, in a large scale implementation, can then be expanded in the turbine section of a turbo-generator.Five consecutive reduction-oxidation cycles between 1000 to 1500 °C and 0.18 to 11 bar are carried out over 24 h. The average energy storage density is 2428 ± 469 MJ/m3. We encountered no technical problems during testing, demonstrating that a realistic engineering implementation of the Mg-Mn-O storage concept, using standard, low-cost, internally insulated carbon steel pressure vessels with heating elements embedded in a packed bed of redox pellets and only using pressurized air and suction for oxidation and reduction, respectively, is feasible meriting further scale-up of the concept.

製糖工場の未利用エネルギーを蓄熱する向流接触式ヒートチャージャーのベンチスケール実証試験と設計

脱炭素社会および持続可能開発目標達成のために，産業排熱や再生可能エネルギーの融通拡大が急務である．未利用熱の融通を拡充するためには，未利用熱発生地と熱需要の間にある時空間的なギャップを解消する蓄熱輸送技術が必要であり，ゼオライトを用いた蓄熱輸送システムに着目した．本研究では蓄熱・出熱のうち，蓄熱側に着目し未利用熱を蓄熱する向流接触式移動床蓄熱装置（ヒートチャージャー）を考案し，ケーススタディとして検討している製糖工場で実環境下においてフルスケールの約1/400規模の実証試験と数値解析によるフルスケールモデルの設計を実施した．実証試験では0.75 kWの連続的な蓄熱に成功した．また，蓄熱装置の性能を予測する数値解析モデルを開発し，充填層半径方向の充填層有効熱伝導を考慮した定常一次元モデルで試験結果を模擬できることを明らかにした．妥当性を確認した定常一次元数値解析モデルを用いてフルスケールのヒートチャージャーを設計した．設計パラメータを整理し，各ゼオライト流量において蓄熱に必要な補助動力を最小化するように可変パラメータである充填層高さ，蓄熱ガス流量を決定する手法を確立した．

Halogenation of used aluminum matrix test reactor fuel – a bench-scale demonstration with surrogate materials

ABSTRACT Experiments with surrogate materials were performed at bench scale to demonstrate a halogenation technique applicable to treatment of used aluminum matrix test reactor fuel. The technique involves dissolution and separation of aluminum from used aluminum matrix test reactor fuel in molten-halide salt systems prior to treatment and disposition of the fuel’s uranium and fission products. Demonstration of the halogenation technique was performed with neodymium metal as a non-radiological surrogate for uranium metal. Experiments involved blending forms of aluminum and neodymium metal with ammonium and lithium chloride or ammonium and lithium bromide, which upon heating decomposed into ammonia gas and the respective hydrogen chloride or bromide gas. The latter reacted with the metals to form the respective aluminum and neodymium halides. At elevated temperatures, aluminum halides gasified away from the respective neodymium halides, which fused with their respective lithium halides. Samples of fused and distillate salts were collected and analyzed, yielding extents of aluminum removal that ranged from 94.5–98.2% for chlorination runs and 91.4–97.8% for bromination runs. No neodymium was detected in the distillate fractions. Some experiments were repeated with excess reactants, and a portion of aluminum chloride distillate was processed into a consolidated waste form.

Electrochemically-mediated amine regeneration of CO2 capture: From electrochemical mechanism to bench-scale visualization study

Electrochemically-mediated amine regeneration (EMAR) is a new CO2 capture technology with the potential to exploit the excellent removal efficiencies of thermal amine scrubbers while reducing parasitic energy losses and capital costs. To achieve higher efficiency and explore the industrial application of the promising EMAR system, a home-designed bench-scale modular flowing-through electrolysis cells (MFTECs) is proposed. The MFTECs with MEA solvent is carefully analyzed from electrochemical mechanism to bench-scale demonstration. Firstly, a series of electrochemical experiments were conducted in an H-cell to study the unknown electrochemical behaviors under various complex concentrations and temperatures, which provided a guidance to enhance the electrochemical performance. Subsequently, a visualization study of the CO2 desorption process in MFTECs was conducted at different operating conditions (current, complex concentration, electrode position, and reaction time) to investigate the desorption performance of the proposed MFTECs system. This framework allowed for direct observation and comprehension of the CO2 desorption process, as well as the movement and interaction of CO2 bubbles in MFTECs. Finally, results indicated that the proposed MFTECs enables higher electrode active surface area and lower cell resistance. This will contribute to enhancing the regeneration performance and promoting industrial application of CO2 desorption based on EMAR.

Bench-Scale Demonstration and Thermodynamic Simulations of Electrochemical Nutrient Reduction in Wastewater via Recovery as Struvite

Land application of manure can be a sustainable supply chain practice that improves soil quality by recycling important nutrients contained in animal waste. Yet, runoff of phosphorus and nitrogen nutrients contained in the animal waste has contributed to significant watershed eutrophication. Recovery of the dissolved nutrient species as a condensed solid fertilizer product would increase sustainability of the agricultural supply chain, while reducing watershed pollution. This study was conducted to evaluate the recovery of phosphorus (primarily) as struvite using an electrochemical process while varying temperature, applied cathodic potential, turbulence and Ca2+ concentration. High phosphorus recovery with high current efficiency and low specific energy consumption was possible at 20 °C, −1.1 V vs Ag/AgCl at the cathode, and a Reynolds number of 9150 in the absence of Ca2+ when the Mg:N:P ratio was 1.37:1:1. Further, a thermodynamic model of the waste solution indicated an increase in Ca2+ concentration, which impedes struvite recovery, can be negated by increasing dissolved Mg2+ concentration and operating at a pH below NH3 volatilization.

Transmission of Images With Ultrasonic Elastic Shear Waves on a Metallic Pipe Using Amplitude Shift Keying Protocol.

Transmission of information using ultrasonic elastic waves on existing metallic pipes provides an alternative communication option across physical barriers in a highly partitioned industrial complex, such as a nuclear facility. This work investigates the feasibility of the transmission of digital images over metallic pipes. Ultrasonic communication systems for transmission of images on a nuclear-grade stainless steel pipe were assembled for bench-scale demonstration. Information carriers in this system are refracted shear waves transmitted and received with piezoelectric transducers (PZTs) operating at 2-MHz nominal frequency. The refraction and propagation of ultrasonic shear waves were modeled with COMSOL software. An amplitude shift keying (ASK) communication protocol for image transmission was developed and implemented in the GNURadio software-defined radio (SDR) environment. Digital information was converted to analog ultrasonic signals using Red Pitaya electronic boards. The performance of the ASK protocol is evaluated at the output of every block in the GNURadio program by monitoring the transmission of select characters. Using the ASK communication protocol, the transmission of the 32-KB image was demonstrated at 2-Kbps bitrate across 6-ft-long stainless steel pipe. Preliminary evaluation of ultrasonic communication on the piping of a nuclear facility, such as signal transmission on bent pipes, was performed with COMSOL computer simulations.

Bench-scale demonstration of CO2 capture with an electrochemically driven proton concentration process.

A thorough experimental investigation of a bench-scale apparatus of the proton concentration process with two symmetrical MnO2 electrodes is presented, with the aim of continuous desorption of CO2 from a K2CO3 solution. The electrodes were fabricated through cathodic deposition, and their chemical states, morphology, and microstructural architecture were characterized with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Successful formation of MnO2 film was confirmed by XPS analysis, and the SEM images showed a uniform distribution of the film across the carbon substrate surface and along the strand, with an average thickness of ∼500 nm, thus making proton ion diffusion possible. Continuous and efficient desorption of CO2 from a K2CO3 solution was obtained when electrodeposited MnO2 electrodes were used in a flow-based proton concentration process. The amount of CO2 desorbed per area of the electrode was 12-fold higher than that of a similar system. The electrochemical nature of the proton concentration process offers substantial practical advantages for the future, especially if electricity can be sustainably produced from renewable sources.

Defect control for large-scale thin-film composite membrane and its bench-scale demonstration

Since the inception of membrane-based CO2 separation technology in the late 1970s, a large number of material studies have been performed to improve the material properties of membrane materials and tremendous progress has been made with regard to CO2 separation to increase the trade-off between permeability and selectivity, known as the “Robeson upper bound.” In membrane science, material properties and membrane properties are related but completely different, especially in thin-film composite (TFC) membranes. Compared to the large number of material studies, few studies have been performed on membrane properties, and very few membranes have been successfully commercialized because an extremely thin selective layer is required in CO2/N2 separation membranes for high CO2 permeance; however, defects are easily generated, deteriorating gas transport properties on a large-scale. In this study, we theoretically analyzed the effect of defects on the gas transport properties of a TFC membrane and introduced a method to control defects during the preparation of large-scale membranes. This work will provide a facile and practical approach to preparing TFC membranes and will be helpful toward extending material studies to real membrane demonstrations.

Continuous process to solidify nuclear waste demonstrated

In a bench-scale demonstration, researchers have successfully used a continuous process to turn 11 L of low-activity radioactive and hazardous chemical waste into a durable glass form. The project marks the first time researchers have used the process to vitrify waste from underground storage tanks at the U.S. Department of Energy’s former weapons plant at Hanford, Wash. Previous tests had been done in batches. The waste remains from nuclear weapons plutonium production stretching back to before the Cold War, and several of the tanks are leaking. More than 20 years in preparation, the continuous approach is designed to become a key part of a treatment chain to address some 210 million L of liquid and semisolid waste held in 177 tanks. The system being constructed at Hanford will use a filtration and ion exchange system to remove solids and cesium from tank waste and pump the resulting low-activity waste to

Development of Post-combustion CO2 Capture System Using Amine-impregnated Solid Sorbent

A new synthetic polyamine was found as a suitable compound for amine-impregnated solid sorbent through screening of amine compounds with the aid of density functional theory calculations. CO2 capture performance of the sorbent was evaluated on a lab-scale CO2 capture system. The solid sorbent was excellently regenerable even at low temperature condition. Then, Bench-scale demonstration will be started on current project, using the sorbent developed by Research Institute of Innovative Technology for the Earth (RITE) and moving bed system of Kawasaki Heavy Industries, Ltd (KHI).

Iron oxide looping for natural gas conversion in a countercurrent moving bed reactor

Chemical looping technologies have the potential to reduce the natural-gas conversion cost in a carbon-constrained scenario. Given the increasing importance of natural gas to global energy supply, this work investigates the application of an iron oxide based chemical looping technology for natural gas conversion. A thermodynamic criterion for selecting iron oxide based oxygen carrier material and designing the reaction system is developed using an adapted Ellingham diagram. Equilibrium modeling for detailed thermodynamic analysis is conducted for verifying the Ellingham diagram analysis. The thermodynamic equilibrium model also establishes a system baseline performance, and experimental proof of concept bench-scale demonstration is investigated. The bench-scale testing is used to characterize the effect of parameters like solids to gas ratio and temperature of the reactor on system performance. An optimal set of operating conditions is identified for further testing on a larger scale.

Bench-scale demonstration of CO2 capture with electrochemically-mediated amine regeneration

Electrochemically-Mediated Amine Regeneration (EMAR) is a new strategy for CO2 separations that uses industrially relevant amine sorbents in a nearly isothermal capture process. The electric nature of the EMAR system offers significant practical advantages in retrofit applications and for installation in non-power generating facilities. EMAR systems are based on an electrochemical copper cycle where desorption is facilitated by oxidation of a copper anode to generate cupric ions that displace CO2 from the polyamine sorbents. The CO2 capacity of the sorbent solution is regenerated through electroplating of the cupric ions onto a separate copper cathode. Results from a bench-scale system demonstrate the potential of the technology for efficient low-energy capture of CO2. The importance of current density and sorbent flow rate are measured. The work of capture increases linearly with current density. For flow rate, however, there is an optimum value of about 1 cm s−1 of superficial velocity through the device. Different electrode geometries and different electrolytes are also examined. At ambient pressure and temperature, which are far from the ideal operating conditions, CO2 can be captured for 100 kJ per mol−1 at a membrane current density of 50 A m−2. The Faradaic (current) efficiencies reach 80% under some conditions with only minimal optimization of the design and materials. This level of performance already meets or exceeds the performance of other electrochemical systems.

A tandem laboratory scale protein purification process using Protein A affinity and anion exchange chromatography operated in a weak partitioning mode

A significant consequence of scaling up production of high titer monoclonal antibody (mAb) processes in existing facilities is the generation of in-process pools that exceed the capacity of storage vessels. A semi-continuous downstream process where columns and filters are linked and operated in tandem would eliminate the need for intermediate holding tanks. This study is a bench-scale demonstration of the feasibility of a tandem process for the purification of mAbs employing an affinity Protein A capture step, followed by a flow-through anion-exchange (AEX) step with the possibility of adding an in-line virus filtration step (VF). All three steps were linked sequentially and operated as one continuous process using an ÄKTA FPLC equipped with two pumps and a system of valves and bypasses that allowed the components to be engaged at different stages of the process. The AEX column was operated in a weak partitioning (WP) mode enabled by a precise in-line titration of Protein A effluent. In order to avoid complex control schemes and facilitate validation, quality and robustness were built into the system through selection of buffers based on thermodynamic and empirical models. The tandem system utilized the simplest possible combination of valves, pumps, controls, and automation, so that it could easily be implemented in a clinical or commercial production facility. Linking the purification steps in a tandem process is expected to generate savings in time and production costs and also reduce the size of quality systems due to reduced documentation requirements, microbial sampling, and elimination of hold time validation.

Conceptual comparison of pink water treatment technologies: granular activated carbon, anaerobic fluidized bed, and zero-valent iron-Fenton process

Pink water, explosive-laden wastewater produced in army ammunition plants is often treated using expensive and non-destructive granular activated carbon (GAC) adsorption. This paper compares GAC adsorption and two alternative treatment technologies, anaerobic GAC fluidized bed reactor and zero-valent iron-Fenton process. The bench-scale demonstration of the zero-valent iron-Fenton process with real pink water is reported. The features of three technologies are compared and their advantages and drawbacks are discussed.

Strontium And Transuranic Precipitation And Crossflow Filtration Of A Large Hanford Tank 241-An-102 Sample#

This work provides an important confirmation of the strontium/permanganate precipitation process to achieve both acceptable filterability and decontamination for Envelope C (Tanks 241-AN-102 and 241-AN-107) complexant wastes to be treated by the Hanford River Protection Project. This bench-scale demonstration contained a series of seven precipitation batches and crossflow filtration campaigns to decontaminate filtrate of Sr-90 and transuranics from 16.5 L of Tank 241-AN-102 supernatant liquid with entrained solids. Batches were caustic adjusted, strontium and permanganate precipitated, and crossflow filtered with entrained solids using a 2-ft long, 3/8″-internal diameter, 0.1-micron pore size Mott crossflow filter tube. Test ranges for the transmembrane pressures and crossflow velocities were in the range of 30 to 70 psid (2.07 to 4.83 bar) and 9 to 15 ft/s (2.7 to 4.6 m/s), respectively. #The submitted manuscript has been authored by a contractor of the U.S. Government under contract No. DE-AC09-96SR18500. Accordingly, the U.S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes.

Bench-scale demonstration of an integrated deSoot–deNOx system

A catalytic deSoot–deNOx system, comprising Pt and Ce fuel additives, a Pt-impregnated wall-flow monolith soot filter and a vanadia-type monolithic NH3-SCR catalyst, was tested with a two-cylinder DI diesel engine. The soot removal efficiency of the filter was 98–99mass% with a balance temperature (stationary pressure drop) of 315°C at an engine load of 55%. The NOx conversion ranged from 40 to 73%, at a NH3/NOx molar ratio of 0.9. Both systems were measured at a GHSV of 52000l/(lh). The maximum NOx conversion was obtained at 400°C. The reason for the moderate deNOx performance is discussed. No deactivation was observed after 380h time on stream. The NOx emission at high engine loads is around 15% lower than that of engines running without fuel additives.

Fundamental Aspects of Dilute Acid Hydrolysis/Fractionation Kinetics of Hardwood Carbohydrates. 1. Cellulose Hydrolysis

Previous kinetic modeling and bench-scale demonstration efforts using batch, percolation, or plug-flow reactors for the dilute sulfuric acid hydrolysis of cellulose have concluded that glucose yields above 70% of theoretical were not possible. This has been explained to be a result of reactions involving glucose or the cellulose itself in a destructive manner, as well as hydrolyzed soluble oligomers which have been modified chemically so as not to release glucose. However, recently, we have demonstrated that near-quantitative yields of glucose from cellulose can indeed be obtained using a bench-scale shrinking-bed percolation reactor in which an internal spring compresses the biomass as the reaction progresses. The present study was initiated to gain a fundamental understanding of the kinetic sequences involved in these high yields. Three reactor configurations (batch, percolation, and shrinking-bed percolation) were studied using similar hydrolysis severities to begin addressing chemical, physical, and h...

Solid-state protonic conductors: principles, properties, progress and prospects

A brief overview is given of the types and principles of solid state protonic conductors. Their properties are summarised in terms of protonic conductivity and operation temperature. A few trends and highlights of the current scientific advances are given for some of the main classes of protonic conductors. Despite our progress, a crucial point still seems to be the ability and computer power required to understand and model the complex quantum mechanical proton transfer process. Many of the commercial prospects are closely connected with the need for cleaner energy technologies and the use of hydrogen as an energy carrier. In particular, polymer-based proton conductors are quickly approaching the market for small fuel cells and electrolysers: from bench-scale demonstration units for hydrogen energy to automobiles. There is also emerging interest in mixed protonic–electronic conductors for use as hydrogen permeable membranes in hydrogen separation technologies. This will also be helpful in the much needed development of electrodes for high- and intermediate-temperature proton conductors.

An Integrated Surfactant Solubilization and PCB Bioremediation Process for Soils

Two decades after the manufacture and use of polychlorinated biphenyls (PCBs) were banned, PCB contamination remains widespread in the environment. Technologies available for PCB remediation are limited and often impractical for soils with dispersed PCB contamination. In this study, two remediation processes have been integrated for use on PCB-contaminated soils. This remediation strategy links in situ surfactant washing of PCBs from soil with aerobic biodegradation of the resulting surfactant-PCB solution by two field application vectors (F A Vs), Pseudomonas putida IFL5::TnPCB and Ralstonia eutropha B30F4::TnPCB, which utilize surfac-tants as growth substrates and cometabolize PCBs. A bench-scale demonstration of this process was performed using PCB-contaminated soils from an electric power substation site. In a 2-day recycling wash using a 1% (wt/vol) surfactant solution, greater than 70% of the PCBs were removed from the soil. In the biodegradation phase, greater than 90% of the surfactant and 35% of the PCBs were biodegraded in 12 days. The residual PCBs were partitioned onto a solid carrier resulting in greater than 90% removal of PCBs from the bioreactor effluent and a 50-fold reduction in the amount of PCB-contaminated material.