Carbon Bed Research Articles

Microfacies of the San Juan Formation (lower Darriwilian) in the Rio Francia section, Central Precordillera, Argentina.

In this contribution, we describe and interpret the microfacies of the upper levels of the San Juan Formation in the Río Francia section of the Central Precordillera, Argentina, for the first time. Several studies in this section identified the Lenodus antivariabilis, Lenodus variabilis, Lenodus crassus, and Lenodus pseudoplanus zones, thereby limiting this stratigraphic interval to the early Darriwilian age. Five microfacies were recognized: M1 burrowed bioclastic wackestone, M2 bioclastic mudstone-wackestone, M3 intrabioclastic grainstone, M4 crinoidal wackestone-packstone, and M5 bioclastic wackestone-packstone. These microfacies indicate a shallow subtidal inner platform environment with variations in hydrodynamic energy ranging from low to moderate conditions below the fair-weather wave base level. The vertical arrangement of these sub-environments suggests a gradual transgressive setting during the lower Darriwilian for the carbonate beds of the San Juan Formation. The Baños de Talacasto, Ancha Creek, and Don Braulio sections are correlated with the section studied in this work, where conodont zones were documented, and microfacies analyses revealed shallow subtidal environments with low-energy conditions and occasional high-energy episodes. Differences in redox conditions were observed between the Don Braulio section (anoxic) and the Río Francia section (well-oxygenated), interpreted as the result of a rapid sea-level rise, though diachronic across the platform. Microfacies analysis, combined with precise conodont biostratigraphy, provides a powerful tool for reconstructing the Middle Ordovician carbonate platform.

The unconventional petroleum system of a mixed siliciclastic-carbonate sequence: Irati Formation, Paraná Basin, Brazil

Widespread rhythmic intercalation of a millimeter- to meter-scale hydrocarbon source rock (organic-rich shale and marlstone) and a carbonate reservoir (micritic and peloidal dolostone) are unusual. Here, the case of the Irati Formation (Paraná Basin) is reported, in which source rock strata have high total organic carbon (averaging 10 to 20 wt%), with dominance of highly oil-prone kerogen type I and II. Multivariate statistical analyses were applied to find patterns in the geochemical multivariate data set. The data points to three main productive sectors in the basin: Paraná Sector, Santa Catarina Sector, and Rio Grande do Sul Sector. Quality, quantity, and petroleum potential vary both laterally and vertically. On the other hand, the reservoir carbonate beds are predominantly composed of low-primary pore space, in which the effective reservoir capacity is determined by the presence of postdepositional secondary porosity. In addition, the Paraná-Etendeka magmatism, which occurred during the break-up of the Atlantic Ocean, played an important role in thermal maturation and primary oil migration.

Performance evaluation and sensitivity analysis of polyethyleneimine-based sorbent in a circulating fluidized bed carbon dioxide capture unit

Greenhouse gases, particularly carbon dioxide, have increased the Earth’s average temperature by 1 °C, which has resulted in significant consequences for human life. To prevent further global warming and maintain a stable lifespan, it is imperative to achieve carbon neutrality. Post-combustion capture using an amine-based aqueous solvent is an advanced technology that has gained attention, but there are challenges such as corrosion, environmental impact, and energy consumption associated with it. This study aims to evaluate the performance of a polyethyleneimine-based sorbent in a circulating fluidized bed carbon dioxide capture unit and to determine the optimal operating conditions through sensitivity analysis. Various variables, including carbon dioxide concentration, water vapor content, desorber temperature, and sorbent residence time, were analyzed. The unit was continuously operated for 128 h even under challenging conditions with higher oxygen concentrations than the actual flue gases, and sorbent degradation was negligible. The results showed a 55 % carbon dioxide removal efficiency, a dynamic sorption capacity of 0.041 g-CO2/g-sorbent, and a regeneration heat energy of 4.2 GJ/tCO2. Sensitivity analysis revealed that there was minimal improvement even with changes in the absorber structure and physical properties of the sorbent. Only an increase in the sorbent reaction rate had a significant effect. If the reaction rate were to double, the carbon dioxide removal efficiency would reach 90 %, with a dynamic sorption capacity of 0.068 g-CO2/g-sorbent and regeneration heat energy of 2.9 GJ/tCO2.

Lower-order transgressive–regressive cycles within a higher-order transgression at the basin margin: an aberrant intercalation of palaeosol and biostromal ichnofabrics from the early Miocene Kutch Basin, India

The Chhasra Formation (CF) of Kutch Basin exemplifies a typical mixed siliciclastic-carbonate system with alternations of biostromal carbonate and fine-grained siliciclastic beds. The CF is subdivided into two members: the lower Claystone (CM) and the upper Siltstone (SM) member. Three CM outcrops (P1-P3) comprising buried palaeosols that formed under a specific environmental set-up involving imperfectly to poorly drained conditions, are exposed along the Berwali River. The biostromal carbonate beds, alternating with the palaeosols, contain invertebrate bioclasts (bivalves, gastropods, echinoids, etc.) and are characterized by a paucispecific firmground Thalassinoides ichnofabric. At section P1, below the contact between the underlying palaeosol and overlying carbonate, Thalassinoides transforms into firmground Gyrolithes inside the palaeosol forming a compound ichnotaxon. The palaeosol intervals of sections P1 and P2 consist of a Vondrichnus‒Termitichnus‒root trace ichnofabric defining the Termitichnus ichnofacies. At section P3, lenses of fully bioturbated siltstones with a monospecific firmground Thalassinoides ichnofabric can be observed within an overall silty palaeosol horizon, thereby, locally cross-cutting the pedogenic features. The ichnofabrics of section P3 indicate polyphase pedogenesis with three stages: (1) initial stage: pedogenesis in siltstone of undefined depositional affinity which was obscured by pedogenic processes, (2) transient stage: recurring marine incursions and colonization by crustaceans within the lens-shaped palaeotopographic depressions overprinting the palaeosol, and (3) final stage: subaerial exposure and another preserved phase of pedogenesis. The CM shows an apparent low-order T–R (transgressive-regressive) cyclicity within a 3rd-order TST (transgressive systems tract) that is supported by pedogenic intensity, ichnofabrics, and reciprocal sedimentation near the Miocene basin margin, though the cyclicity can be the result of both autogenic and/or lower-order allogenic changes.

Efficient Electrochemical Reduction through Flow Cells Using Spherical-Polymer Based Carbon Supported Catalysts as Fixed-Bed Electrode

The transition to economically friendly feedstocks and the electrification of chemical synthesis reactions gained much attention in the recent years. To be able to compete with the conventional processes, it is crucial not only to concentrate on the electrochemical reactions itself but also to constantly improve the reactor concepts. A vast variety of designs are imaginable and already well-described – from a simple, undivided beaker cell setup to a divided flow cell with separate electrolytes at cathode and anode. [1] As electrode material not only flat metal electrodes are studied, but also the concept of using carbon supported metal nanoparticles is well-known to employ high dispersion to lower the total amount of required metal. [2,3] While there are already commercial flow reactors and electrodes available for electrosynthesis with flat standard electrodes, reactors using a fixed-bed of porous carbon with nanodispersed metals as electrode just recently started to attract attention. [4] Dealing with the pressure drop over the catalyst bed, while the electrical contact is still ensured, are key challenges for this reactor design. Spherical polymer-based carbons (SPBC) combine porous carbons properties with a high purity and especially spherical character. [5] While these advantages led already to commercial products for chromatographic applications (e.g. Carboxen®) the potential regarding flow-electrochemistry has not been leveraged. Key developments for this are reproducible synthesis procedures to deposit active metal on the SPBCs and the design of an electrochemical flow cell using these catalysts in a fixed-bed electrode configuration.The first part of this work presents the deposition of Cu through different impregnation and reduction procedures on a SPBC (Carboxen® 1032, 50 µm, Merck). The carbon was characterized by physisorption, TPD-MS, TPO, Raman and SEM. The resulting metal-impregnated carbon catalysts were additionally investigated regarding the metal loading. Using the applied impregnation and reduction parameters targeted metal loadings (3 – 20 wt%) could be well achieved. The second part focuses on the design and commissioning of a flow-cell for the application of the SPBC-supported catalysts as a fixed-bed at the cathode side. Electrochemical synthesis reactions are targeted in the cell and the reduction of 5-HMF to BHMF was chosen as the test reaction in this work. In the framework of the cell development multiple aspects not only regarding the construction but also reaction engineering issues had to be considered: material stability of the pump, fixation and pressure drop of catalyst bed, choice of electrolyte, effect of dissolved oxygen in the catholyte, optimal flow rate, reliable electrochemical protocol and selection of contact material. The latter has to be a compromise between chemical inertness and an enhanced electron transfer between the catalyst bed and the contact material (e.g. soft foil vs. hard metal). Figure 1A shows the current voltage characteristics of two possible contact materials (graphite foil, boron-doped diamond (BDD)) in the targeted electrolyte (0.5M borate buffer with 0.25M potassium chloride). Here, the graphite foil clearly shows a higher activity towards the hydrogen evolution reaction which may result in a less effective electrolysis later on. The comparison of BDD as contact material without and with a catalyst bed (Carboxen® 1032 loaded with 20 wt% Cu) resulted in a significant shift in the current voltage characteristic to lower overpotentials. Therefore, the electronic contact with the carbon bed is clearly enabled and the carbon spheres loaded with copper catalyze the reaction. Figure 1B presents the results of the test reaction with the conversion of the educt 5-HMF as well as the selectivity to the targeted product BHMF over the reaction time with BDD as contact material without and with a fixed bed of Cu/SPBC catalyst. The experiments prove full 5-HMF conversion within 23 h on stream in combination with a high selectivity towards BHMF with the catalyst bed. The mass-based productivity reaches values of up to 1.78 mmol h-1 gCu -1 and is therefore about 15 times higher compared to the use of conventional Cu foil (Pliterature = 0.11 mmol h-1 gCu -1 [6]). It is possible that due to the metal-support approach in the fixed-bed configuration, the copper is leveraged more efficiently and small amounts allow to provide sufficient metal surface area for the catalytic reaction.

Investigating the Effects of the Physicochemical Properties of Cellulose-Derived Biocarbon on Direct Carbon Solid Oxide Fuel Cell Performance.

This paper presents a study of the characteristic effects of the physicochemical properties of microcrystalline cellulose and a series of biocarbon samples produced from this raw material through thermal conversion at temperatures ranging from 200 °C to 850 °C. Structural studies revealed that the biocarbon samples produced from cellulose had a relatively low degree of graphitization of the carbon and an isometric shape of the carbon particles. Based on thermal investigations using the differential thermal analysis/differential scanning calorimeter method, obtaining fully formed biocarbon samples from cellulose feedstock was possible at about 400 °C. The highest direct carbon solid oxide fuel cell (DC-SOFC) performance was found for biochar samples obtained via thermal treatment at 400-600 °C. The pyrolytic gases from cellulose decomposition had a considerable impact on the achieved current density and power density of the DC-SOFCs supplied by pure cellulose samples or biochars derived from cellulose feedstock at a lower temperature range of 200-400 °C. For the DC-SOFCs supplied by biochars synthesised at higher temperatures of 600-850 °C, the "shuttle delivery mechanism" had a substantial effect. The impact of the carbon oxide concentration in the anode or carbon bed was important for the performance of the DC-SOFCs. Carbon oxide oxidised at the anode to form carbon dioxide, which interacted with the carbon bed to form more carbon oxide. The application of biochar obtained from cellulose alone without an additional catalyst led to moderate electrochemical power output from the DC-SOFCs. The results show that catalysts for the reverse Boudouard reactions occurring in a biocarbon bed are critical to ensuring high performance and stable operation under electrical load, which is crucial for DC-SOFC development.

Efficient Transformation of Water Vapor into Hydrogen by Dielectric Barrier Discharge Loaded with Bamboo Carbon Bed Structured by Fibrous Material.

A new method of efficiently transforming water vapor into hydrogen was investigated by dielectric barrier discharge (DBD) loaded with bamboo carbon bed structured by fibrous material in an argon medium. Hydrogen productivity was measured in three different reactors: a non-loaded DBD (N-DBD), a bamboo carbon (BC) bed DBD (BC-DBD), and a quartz wool (QW)-loaded BC DBD (QC-DBD). The effects of the quality ratio of BC to QW and relative humidity on hydrogen productivity were also investigated in QC-DBD at various flow rates. The reaction process and mechanism were analyzed by scanning electron microscopy, X-ray photoelectron spectroscopy, N2 physisorption experiments, infrared spectroscopy, and optical emission spectroscopy. A new reaction pathway was developed by loading BC into the fibrous structured material to activate the reaction molecules and capture the O-containing groups in the DBD reactor. A hydrogen productivity of 17.3 g/kWh was achieved at an applied voltage of 5 kV, flow rate of 4 L/min, and 100% relative humidity (RH) in the QC-DBD with a quality ratio of BC to QW of 3.0.

Water Condenser Bed to Reduce Trichloroethylene Gas Emission and Air Quality

Purpose: The purpose of this research is how to reduce trichloroethylene emissions using a condenser and the efficiency of reducing trichloroethylene emissions before and after using a condenser. Theoretical Framework: Air quality is influenced by trichloroethylene emissions, condenser and efficiency, trichloroethylene emissions, and condenser. Method: The research carried out was quantitative descriptive research. Data Source: Literature Study; Field observation; Trichlorethylene gas recovery process in existing systems in the field such as dryer units, carbon bed units and added condenser units. Sampling method with Trichlorethylene, Gas Emission, Concentration Measurement. Results and Discussion: The efficiency value of reducing the trichloroethylene gas emission load before and after adding the condenser reached 68.16%. The emission load on the chimney before adding the condenser was an average of 223 kg/day and after adding the condenser an average of 71 kg/day. Research Implications: The efficiency of reducing the trichloroethylene gas emission load is influenced by several supporting factors, namely the temperature of the condenser cooling water and the surface area of the cooling water tube pipe. Originality/Value: The Electric Accumulator Component Industry with products in the form of sheet-shaped Electric Accumulator Separators made from polymer powder, silica powder, oil, and other supporting materials with the production capacity will affect the formation of the solution.

Study on the regeneration of activated carbon adsorbed with radon by using a deep depressurization method

ObjectiveTo develop a heating-free, rapid, and efficient method for the regeneration of activated carbon by introducing deep depressurization. MethodsA validation experimental setup was designed to systematically investigate the impacts of various desorption methods, durations, and conditions on the desorption effectiveness of activated carbon with adsorbed radon and water. Consecutive repetitive and expanded experiments were carried out. ResultsThe combination of continuous ventilation and deep depressurization was proved the most effective in the desorption of activated carbon. Considering factors such as overall energy consumption and time, the optimal desorption duration for activated carbon was determined at 2 ​h. Reducing the relative humidity of radon-laden air and increasing the desorption environmental temperature significantly enhanced the desorption rate. Under a temperature range of 24–25°C, a relative humidity range of 5%–15%, and a flow rate of 0.3 ​L/min, a desorption rate of 85% was achieved for 122.5 ​g of activated carbon after 2 ​h of desorption. Moreover, the desorption results remained stable throughout 10 repetitions. Further experiments on a kilogram-scale activated carbon bed demonstrate that under a vacuum level meeting the requirement for moisture evaporation and an appropriate flow rate, the desorption rate of the activated carbon reached that of a smaller activated carbon bed, independent of the shape of the activated carbon bed. ConclusionThe deep depressurization method shows great promise as a rapid and efficient online method for the regeneration of activated carbon with adsorbed radon and water.

Treatment of Tile type C pelvic ring fracture using orthopedic robot combined with Starr pelvis reduction frame

To investigate the clinical effect of orthopedic robot combined with Starr pelvic reduction frame in the treatment of Tile type C pelvic ring fracture. From October 2019 to May 2021, 14 patients with type C pelvic ring fracture were treated with robotic combined with Starr pelvic reduction frame, including 9 males and 5 females. The age ranged from 33 to 69 years. All the 14 patients had fresh closed fractures without femur, tibia and fibula fracture. Surgery was completed from 4 to 7 d after hospital admission. During the operation, the X-ray carbon bed was used, the pelvic ring was reduced by Starr pelvis reduction frame, and pelvic ring fracture was treated by orthopedic robot. Operation time, bleeding volume, fluoroscopy times of single screw placement, fracture reduction quality, affected limb function and complications were observed. Radiological reduction was evaluated using Matta scoring standard, and clinical efficacy was evaluated by Majeed pelvic function scoring system at the final follow-up. All of 14 patients successfully completed the operation, the operation time was 84 to 141 min, the bleeding volume was 20 to 50 ml, and the fluoroscopy times of single screw insertion was 4 to 9 times. All of 14 patients were followed up for 12 to 24 months. The healing time was 3 to 7 months. No complications such as fracture of internal fixation, screw loosening, infection and nerve injury were found. According to the evaluation criteria of Matta imaging reduction, 9 cases were excellent, 4 cases were good, and 1 case was fair. At the final follow-up, Majeed pelvic function scoring system was used:10 cases were excellent, 4 cases were good. The treatment of type C pelvic ring fracture with robotic combined Starr pelvis reduction frame is simple, time-saving, less trauma, less complications and effective.

Comparing the performance of fluidized and fixed granular activated carbon beds as cathodes for microbial electrosynthesis of carboxylates from CO2

Microbial electrosynthesis (MES) can use renewable electricity to power microbial conversion of carbon dioxide (CO2) into carboxylates. To ensure high productivities in MES, good mass transfer must be ensured, which could be accomplished with fluidization of granular activated carbon (GAC). In this study, fluidized and fixed GAC bed cathodes were compared. Acetate production rate and current density were 42 % and 47 % lower, respectively, in fluidized than fixed bed reactors. Although similar microbial consortium dominated by Eubacterium and Proteiniphilum was observed, lowest biomass quantity was measured with fixed GAC bed indicating higher specific acetate production rates compared to fluidized GAC bed. Furthermore, charge efficiency was the highest and charge recovery in carboxylates the lowest in fixed GAC beds indicating enhanced hydrogen evolution and need for enhancing CO2 feeding to enable higher production rates of acetate. Overall, fixed GAC beds have higher efficiency for acetate production in MES than fluidized GAC beds.

Technical and Economic Aspects of Environmentally Sustainable Investment in Terms of the EU Taxonomy

Removing impurities that occur in landfill gas, from sulphur and silicon compounds, is crucial for the energetic use of biogas in a cogeneration unit for energy purposes. The aim of this study was to analyse the shaped activated carbon, examining its structure and elemental composition as part of the biogas purification. The qualitative study of the purified landfill gas performed in this study showed a significant overshoot of hydrogen sulphide at 304.1 ppm with respect to the gas engine manufacturer’s requirements, while the calculated hydrogen sulphide reduction efficiency was 24.58%. Examination of the surface of the spent carbon and its pores with a scanning microscope revealed a high level of clotting by sulphur compounds, which prevents proper reduction of this compound and reduces the efficiency of the treatment plant. Replacement of the activated carbon bed with a new one showed a hydrogen sulphide value of 7.5 ppm in the purified gas and a calculated reduction efficiency of 97.9%. The results of the study confirmed that continuous monitoring of the quality of the purified gas is necessary to control the adsorption properties of the activated carbon and can be used for the operation of gas engines in cogeneration units. The landfill gas treatment method described in this paper constitutes an environmentally sustainable project within the meaning of the EU regulation on the establishment of a framework to promote and facilitate this type of investment in terms of its financing and operation. The topic of the work fits into three key areas of broad research and implementation activities. The first, technological, is the transition to a low-carbon, sustainable and resource-efficient closed-loop economy; the second, environmental, pollution prevention and control. The third area is economics and finance in terms of making financial products available designed to reduce climate change and reporting on these activities.

Dynamic simulation and analysis of dichloromethane-acetone, dichloromethane-trichloromethane and dichloromethane-toluene VOC mixture abatement systems under transient feed conditions

Minimisation of environmental footprint in line with sustainability goals rests at the top of the agenda of the pharmaceutical industry. Volatile Organic Compounds (VOCs), while essential to primary pharmaceutical manufacturing, are solvents whose emissions pose a risk to human health and ecosystems. Adsorption on activated carbon beds is an established technology for end of pipe emissions control, which, however, faces efficiency limitations by quick and irregular bed saturation due to complex, transient feeds. This study employs a validated nonisothermal, multicomponent adsorption model to quantitatively assess the exact effect and potential value of waste stream feed sequencing towards activated carbon bed utilisation optimisation. Our results indicate that gradual increase of dichloromethane feed concentration in combination with a low, constant inlet concentration of the strongly adsorbing component leads to the latest breakthrough onset for the dichloromethane-acetone, dichloromethane-chloroform and dichloromethane-toluene mixtures. Transient vs. constant feeds usage and their interplay clearly affects bed behaviour, paving the way to industrial VOC emission abatement scheduling and process optimisation.

Improving Microstructural Homogeneity of Investment‐Cast Single‐Crystalline Ni‐Base Superalloys by Using Fluidized Carbon Bed Cooling

One impeding factor for faster solidification in typical investment casting processes is the limited heat removal capability. This study compares the classical Bridgman technique and the fluidized carbon bed cooling (FCBC) casting method. In particular, the influence of the thermal design is investigated in terms of microstructural and compositional homogeneity in single‐crystalline CMSX‐4. These investment casting processes mainly differ in the baffle type used to insulate the hot and cold zones inside of the casting vessel. While the Bridgman process is based on radiation cooling, the FCBC casting process relies on a dynamic baffle made of expanded graphite that is buoyant on fluidized bed of glassy carbon beads. Such a dynamic insulation layer can adapt to the cross‐sectional variation of ceramic shell molds and provide a better thermal insulation, which results in more uniform solidification conditions. This enables a reduction in the primary dendrite arm spacing by up to 26%, an increase in the homogeneity of the microstructure and composition, as well as a reduction in overall porosity and mean pore size of 41%.

Sounding out horse mussel sediment thickness: an integrated data approach

Horse mussel beds are listed as a Priority Marine Feature (PMF) in Scotland for their influence in the creation of diverse benthic communities and provision of ecosystem services. In Scotland, horse mussel beds are also recognised for their importance in marine carbon sequestration. Unfortunately, there is a paucity of data on horse mussel bed carbon stocks and sediment thickness. There are also significant financial and logistical barriers with which to address these data gaps. This study investigates the robustness of Sub-Bottom Profiling (SBP) as a cost-effective method to quantify horse mussel sediment thickness across a landscape. Integrating SBP and Drop-Down Video (DDV) data, this study also details an integrated approach to investigate the links between horse mussel habitat condition and sediment thickness. With the addition of abiotic data, this study uses Structural Equation Modelling (SEM) to elucidate key relationships between abiotic factors, biotic variables, and sediment thickness. There is a significant positive correlation of horse mussel habitat condition and sediment thickness. Average horse mussel total sediment thickness, across all measures of habitat condition, was 1.37m. These findings substantially increase previous estimates of horse mussel sediment thickness, and potential value to climate change mitigation through blue carbon frameworks. This study highlights the importance of both abiotic and biotic factors on marine carbon sediment quantification.

Supply Chain-Based Coral Conservation: The Case of Mozuku Seaweed Farming in Onna Village, Okinawa

Blue foods, including seaweed, have been overlooked in food systems analysis and policy-making due to a lack of available data. However, seaweed cultivation is gaining attention as a restorative aquaculture that could contribute to ocean health by serving as blue carbon or nurturing seagrass beds. Commercial restorative aquaculture may provide market-based solutions for improving ocean health. The Onna Village Fisheries Cooperative producers have been restoring corals, knowing empirically that when the coral weakens, the yield of Mozuku seaweed drops. Furthermore, measures taken to reduce red soil run-off prevent the reduction in Mozuku quality and quantity and protect seagrass beds, since Mozuku cultivators have continued to use them as an important nursery. The fishery cooperative and the seaweed processing company, Igeta Takeuchi Co., Ltd., have jointly developed high-quality Mozuku that is resistant to climate change and extreme weather conditions through strain selection. Based on this case, this paper examines the following questions: (1) What quality assurance technique is necessary to continue restorative aquaculture as a market-based solution over the long term? (2) What social platforms and communication channels are available to stakeholders to maintain restorative aquaculture in the long run? To answer these questions, Japanese consumer cooperatives that established “the Mozuku Fund” are also examined. This case study of Mozuku highlights how the sustainability and quality of marine products are maintained throughout the whole supply chain, focusing on the power of the Japanese consumers’ cooperative.

Variable pressure foaming on functionality and structural properties correlation in flexible polyurethane foam

The production cost of flexible polyurethane foam is significantly dependent on the cost of polyol, which constitutes the largest percentage of materials used in foam production with the characteristics to induce superior mechanical properties. Suitable fillers that are relatively cheap can be introduced in the foam as replacement for polyol. Certain compositions of filler have deleterious effect on some relevant mechanical properties of the foam. This paper investigates the Effects of Variable Pressure Foaming on functionality and structure property correlation in polyurethane foam using different percentage of inorganic fillers at different pressure in flexible polyurethane foam for the dual purposes of achieving sustained mechanical properties of polyurethane foam and reduction in the production cost by using the VPF Technique. Government restricts the use of certain auxiliary blowing agents like chlorofluorocarbon, trichloroethane, carbon dioxide, methylene chloride, acetone, pentane and water. VPF machine, in which we can make different densities of foam without adding auxiliary blowing agents which are banned in the Europe and other countries. These blowing agents are highly carcinogenic and ozone depletors, which are also harmful for human beings’ health and greenhouse effect. Water is a natural blowing agent, producers have tried to raise the water level substantially as an ABA agent, With the high exotherm associated with high water level formulations, there is so much urea formation that it is difficult to make flexible PU foams and inferior foam quality and durability, scorching in the foam and pose a fire hazard during foam manufacturing. For the rapid cooling process, it required excess Toluene Diisocyanate usage and allowed excess TDI vapour to be released into the atmosphere. In VPF, enclosed chamber and the exhaust is vented through carbon beds, it filters the TDI fumes which are very harmful for human beings’ health and for the environment. Foams can be achieved by foaming under vacuum, thus substantially reducing the water level and TDI usage. VPF technique offers a unique combination of environmental friendliness, superior product consistency and unique foam properties. It provides us with a platform for new product technology and a reliable process to meet the increasingly stringent environmental regulations.

CFD simulation of a circulating fluidized bed carbon capture system using a solid-supported amine sorbent

Carbon capture, utilization, and sequestration (CCS) is one of the key technologies to reduce the emission of carbon dioxide, including that from exiting flue gas of fossil fuel-fired power plants. In this study, the two-fluid model approach was used to simulate the hydrodynamics of the entire circulating fluidized bed (CFB) loop of the integrated carbonation and regeneration sections using the mass and momentum equations and constitutive relations for both the gas and solid phases. Then, the verified models of the non-reactive simulation of the CFB loop were combined with species, energy equations, and carbonation regeneration rate of reactions for both phases to simulate the entire circulating fluidized bed carbon capture unit. The predicted extent of CO2 capture in this system showed the potential of continuous carbon capture using amine-based solid sorbents through the circulating fluidized bed CO2 capture unit.

Tectonic control on the palaeogeographic evolution of thrust‐top basins at the active margin of the Guadalquivir Basin (central Betic Cordillera, S Spain)

AbstractThe Guadalquivir Basin is the foreland basin of the Betic Cordillera (S Spain). Closest to the orogen, several thrust‐top basins evolved during the Late Miocene in the central part of the cordillera. Here, we study the Upper Miocene deposits in five of these satellite basins: Montefrío, Iznájar‐Cuevas de San Marcos, Antequera, Bobadilla Estación and Teba, in order to (1) update the stratigraphic framework, (2) infer a depositional model, (3) establish the relationship between sedimentary record and tectonic context and (4) reconstruct the palaeogeography of the area during the Late Miocene. Upper Miocene sediments mostly consist of mixed carbonate‐terrigenous deposits. Facies characterization allows inferring a sedimentary model corresponding to a ramp with foreshore deposits changing to a shoal belt offshore in the inner ramp. Swaley and hummocky cross‐stratified deposits formed in the transition to the middle ramp, and plane parallel carbonate beds in the distal middle‐outer ramp. Factory facies, dominated by rhodoliths and bryozoans, also occur in the middle‐outer ramp environments. Silts and marls formed in the deepest outer ramp and basin settings respectively. Breccias accumulated at the toe of palaeocliffs and conglomerates and massive coarse sands were deposited in fluvio‐deltaic systems. Conglomerates and sands were also reworked as gravity flows and redeposited offshore. Local facies include rudstones‐grainstones displaying large‐scale trough‐cross bedding formed in a strait in Montefrío, and marls with chalky carbonates deposited in a shallow marine, sheltered lagoon with hydromorphic soils in Bobadilla Estación. The study basins evolved in an N‐S compressive tectonic context responsible of the emersion of the main Betic reliefs. Concomitantly, E‐W and ESE‐WNW extension originated the main depocentres. The influence of the tectonic activity on the sedimentary infills is indicated by the presence of synsedimentary deformations and several diachronic unconformities, which are younger westward. Tectonism, in turn, also controlled the palaeogeographic evolution during the late Tortonian‐early Messinian interval.

Novel electrochemical strategies for the microbial conversion of CO2 into biomass and volatile fatty acids using a fluid-like bed electrode in a three-phase reactor.

Microbial electrosynthesis (MES) constitutes a bioelectrochemical process where bacteria uptake electrons extracellularly from a polarized electrode to incorporate them into their anabolic metabolism. However, the efficiency of current MES reactor designs can be lower than expected due to limitations regarding electron transfer and mass transport. One of the most promising bioreactor configurations to overcome these bottlenecks is the Microbial Electrochemical Fluidized Bed Reactor (ME-FBR). In this study, microbial CO2 fixation is investigated for the first time in a ME-FBR operated as a 3-phase reactor (solid-liquid-gas). An electroconductive carbon bed, acting as a working electrode, was fluidized with gas and polarized at different potentials (-0.6, -0.8 and -1 V vs. Ag/AgCl) so it could act as an electron donor (biocathode). Under these potentials, CO2 fixation and electron transfer were evaluated. Autotrophic electroactive microorganisms from anaerobic wastewater were enriched in a ME-FBR in the presence of 2-bromoethanosulfonic acid (BES) to inhibit the growth of methanogens. Cyclic voltammetry analysis revealed interaction between the microorganisms and the cathode. Furthermore, volatile fatty acids like propionate, formate and acetate were detected in the culture supernatant. Acetate production had a maximum rate of ca. 1 g L-1 day-1 . Planktonic cell biomass was produced under continuous culture at values as high as ca. 0.7 g L-1 dry weight. Overall, this study demonstrates the feasibility of employing a fluidized electrode with gaseous substrates and electricity as the energy source for generating biomass and carboxylic acids.