Reactor Design

The efficiency of using different feed strategies was evaluated in the case of a gas-phase biofilter packed with an inert carrier material. During a preliminary control-period, the biofilter was first fed with a single downflow feed of toluene. Reactor performance and biomass distribution were evaluated. The feed was then split into two flows before entering the reactor. Different feed ratios were tested during a 6-month period, following the preliminary control stage. Splitting the feed into equal flow rates through the upper and middle part of the biofilter (in a 50 : 50 ratio) improved the performance compared with the single-feed period. Such a high performance could also be maintained when using a higher flow rate for the upper port than for the middle port, with a feed-ratio of approximately 70 : 30, when more biomass was formed in the upper half of the filter bed. However, performance decreased when inverting this ratio from 70 : 30 to 30 : 70, ie when the highest flow rate was fed through the middle port of the biofilter.

Hybrid kinetic models, linking structured models of cell (nano-scale) metabolic processes to the dynamics of macroscopic variables of the bioreactor, are proven to lead to more precise predictions of all key-species dynamics under variable operating conditions, being of an exceptional importance in engineering evaluations to in-silico (math-model-based) determine the optimal operating mode of a fed-batch bioreactor (FBR). Even if such extended dynamic models require more experimental and computational efforts, their use has proven to be advantageous. The approached probative example refers to the simulation of the dynamics of some key species of the central carbon metabolism (CCM) of a modified E. coli cell, linked to the state variables of a FBR used for the tryptophan (TRP) production. By using several optimization algorithms, and an original application of the Paretooptimal front technique, this paper compares various operating alternatives by using multiple control variables, aiming to maximize TRP production, with minimum substrate consumption. The used E. coli strain was modified to drastically amplify the glucose (GLC) uptake into the cell.

Scaling-up engineering systems from laboratory-scale to industrial-scale is a critical step in transforming theoretical concepts into commercially viable solutions. This process requires an integrated approach that addresses a wide range of challenges across several scientific disciplines, including mechanical flow dynamics, heat transfer, chemical kinetics, thermodynamics, and system modeling, simulation, testing, and validation. This paper explores the key methodologies, challenges, and best practices associated with scaling-up, emphasizing the importance of a holistic, multidisciplinary knowledge base in addressing issues such as system behavior changes, material constraints, energy efficiency optimization, economic constraints, and safety compliance. By examining case studies from various industries, we highlight the importance of maintaining process integrity, optimizing energy efficiency, and mitigating risks associated with large-scale implementation. The discussion also covers advanced modeling techniques, regulatory considerations, and innovative approaches that facilitate successful scaling. This work serves as a comprehensive guide for engineers, researchers, and d ecision-makers seeking to navigate the complexities of scaling-up engineering systems efficiently and effectively.

An innovative enzymatic polycondensation of dicarboxylic acids and dialcohols in aqueous polymerization media using free and immobilized lipases was developed. Various parameters (type of lipases, temperature, pH, stirring type and rate, and monomer carbon chain length) of the polycondensation in an oil-in-water (o/w) miniemulsion (>80% in water) were evaluated. The best results for polycondensation were achieved with an equimolar monomer concentration (0.5 M) of octanedioic acid and 1,8-octanediol in the miniemulsion and water, both at initial pH 5.0 with immobilized Pseudozyma antarctica lipase B (PBLI). The synthesized poly(octamethylene suberate) (POS) in the miniemulsion is characterized by a molecular weight of 7800 g mol−1 and a conversion of 98% at 45 °C after 48 h of polycondensation in batch operation mode. A comparative study of polycondensation using different operation modes (batch and fed-batch), stirring type, and biocatalyst reutilization in the miniemulsion, wate...

An innovative enzymatic polycondensation of dicarboxylic acids and dialcohols in aqueous polymerization media using free and immobilized lipases was developed. Various parameters (type of lipases, temperature, pH, stirring type and rate, and monomer carbon chain length) of the polycondensation in an oil-in-water (o/w) miniemulsion (>80% in water) were evaluated. The best results for polycondensation were achieved with an equimolar monomer concentration (0.5 M) of octanedioic acid and 1,8-octanediol in the miniemulsion and water, both at initial pH 5.0 with immobilized Pseudozyma antarctica lipase B (PBLI). The synthesized poly(octamethylene suberate) (POS) in the miniemulsion is characterized by a molecular weight of 7800 g mol−1 and a conversion of 98% at 45 °C after 48 h of polycondensation in batch operation mode. A comparative study of polycondensation using different operation modes (batch and fed-batch), stirring type, and biocatalyst reutilization in the miniemulsion, wate...

Even with the extremely difficult conditions required to initiate and maintain a
controlled nuclear fusion reaction, the opportunity of having a viable energy source
that will last for millions of years continues to provide the main initiative for
continuing research and development in the field.

Because the fuel is available in almost unlimited supply, I believe that fusion
energy will become the major power source of the future long after the petroleum
sources have depleted and made the internal combustion engine obsolete. Not only is this energy source "clean" and environmentally friendly it also has the potential for
higher efficiency in the fuel utilization; nothing is wasted in the conversion process.
Nuclear fusion has been attained on the earth in the form of the hydrogen bomb. The
Bomb is a form of uncontrolled fusion which has no practical value except to make
large holes in the ground quickly and to create Electromagnetic Discharges.

Controlled fusion presents unique problems which scientists have yet to solve. Once the problems are solved, fusion power promises to be a source of energy that could be used for a variety of useful productive purposes.

An innovative enzymatic polycondensation of dicarboxylic acids and dialcohols in aqueous polymerization media using free and immobilized lipases was developed. Various parameters (type of lipases, temperature, pH, stirring type and rate, and monomer carbon chain length) of the polycondensation in an oil-in-water (o/w) miniemulsion (>80% in water) were evaluated. The best results for polycondensation were achieved with an equimolar monomer concentration (0.5 M) of octanedioic acid and 1,8-octanediol in the miniemulsion and water, both at initial pH 5.0 with immobilized Pseudozyma antarctica lipase B (PBLI). The synthesized poly(octamethylene suberate) (POS) in the miniemulsion is characterized by a molecular weight of 7800 g mol-1 and a conversion of 98% at 45 • C after 48 h of polycondensation in batch operation mode. A comparative study of polycondensation using different operation modes (batch and fed-batch), stirring type, and biocatalyst reutilization in the miniemulsion, water, and an organic solvent (cyclohexane:tetrahydrofuran 5:1 v/v) was performed. Regarding the polymer molecular weight and conversion (%),batch operation mode was more appropriate for the synthesis of POS in the miniemulsion and water, and fed-batch operation mode showed better results for polycondensation in the organic solvent. The miniemulsion and water used as polymerization media showed promising potential for enzymatic polycondensation since they presented no enzyme inhibition for high monomer concentrations and excellent POS synthesis reproducibility. The PBLI biocatalyst presented high reutilization capability over seven cycles (conversion > 90%) and high stability equivalent to 72 h at 60 • C on polycondensation in the miniemulsion and water. The benefits of polycondensation in aqueous media using an o/w miniemulsion or water are the origin of the new concept strategy of the green process with a green product that constitutes the core of the new greener polymer-5B technology.

This paper analyzes the behavior of the entropy of a nuclear fuel rod under deep burnup conditions, beyond standard operational ranges, reaching up to 60 years. The evolution of the neutron source distribution in a pressurized water reactor (PWR) fuel pin was analyzed using the Monte Carlo method and Shannon information entropy. To maintain proper statistics, a novel scaling method was developed, adjusting the neutron population based on the fission rate. By integrating reactor physics with information theory, this work aimed at the deeper understanding of nuclear fuel behavior under extreme burnup conditions. The results show a “U-shaped” entropy evolution: an initial decrease due to self-organization, followed by stabilization and eventual increase due to degradation. A minimum entropy state is reached after approximately 45 years of pin operation, showing a steady-state condition with no entropy change. This point may indicate a physical limit for fuel utilization. Beyond this point, entropy rises, reflecting system degradation and lower energy efficiency. The results show that entropy analysis can provide valuable insights into fuel behavior and operational limits. The proposed scaling method may also serve to control a Monte Carlo simulation, especially for the analysis of long-life reactors.

This paper describes an automatic sampling system for anaerobic reactors that allows taking representative samples following the guidelines of Gy's (1998) theory of sampling. Due to the high heterogeneity degree in a digester the sampling errors are larger than the analysis error, making representative sampling a prerequisite for successful process control. In our system, samples are automatically processed, generating a higher density of data and avoiding human error by sample manipulation. The combination of a representative sampling system with a commercial automate titration unit generates a robust online monitoring system for biogas plants. The system was successfully implemented in an operating biogas plant to control a feeding-on-demand biogas system.

Se determinó la capacidad de biorremediación de colorantes azoicos
en agua residual simulada de la industria textil por parte de la
microalga Chlorella vulgaris. Después del escalamiento y adaptación
del cultivo, se evaluó la remoción del colorante Turquesa Erionyl a
través de la medición del cambio de la absorbancia después de 15
días. Se determinó el efecto de la concentración del colorante (30,
70 y 130 ppm) y del pH a un valor de 9 comparado con el pH natural
de 8,3. El mayor porcentaje de remoción alcanzado fue 91,7 % con
una concentración de 70 ppm de colorante y un pH inicial de 9,
mientras que el menor porcentaje de remoción fue de 51,5 % con unaconcentración de 130 ppm del colorante y el mismo pH. Se concluye
que la microalga Chlorella vulgaris posee una considerable capacidad
de remoción de este colorante azoico bajo agua residual simulada de
la industria textil.
Palabras clave: teñido; industria textil; biorremediación; absorbancia

A novel reactor was designed and implemented for water purification using deep ultraviolet light emitting diodes (LEDs). The focus was on minimizing the number of LEDs required for effective germicidal action. Simulation studies were carried out on the flow of water as well as the irradiance of UV. Variation was made in the beam divergence of the UV sources and reflectivity of optical coatings used for photon recycling. Based on optimized reactor designs, water purification was carried out both in the static and flow-through configuration. Water from various sources was spiked with a known bacterial strain, exposure studies were carried out and germicidal effect was determined. Our results indicate that under optimal design, a 3 mL volume of water shows a three order inactivation using a single UV-LED in a static reactor in 180 s. For a flow-through geometry, only three LEDs were used in the reactor implementation, and a multi-pass procedure was used to purify 150 mL of water from an Escherichia coli CFU count of 4.3 × 10 4 /mL to 12/mL. While slow, this process requires less than 2 W, and can be powered from rechargeable sources. Faster processes can be implanted using multiple such reactor units in parallel, and can be optimized to the requirement and power levels.

The different steps for manufacturing a microchannel reactor for the PROX reaction are discussed. Transient Liquid Phase bonding (TLP) using a NiB -Si amorphous melt spun is used for joining micromilled Al-alloyed ferritic stainless steel plates followed by recrystallization at 1200ºC for 5 hours. A CuO x-CeO 2 catalyst synthesized by the coprecipitation method was washcoated on the microchannel block resulting in a homogenous 20-30 µm thick layer. The catalytic activity for CO-PROX reaction is similar in both the powder catalyst and the microchannel coated reactor but the selectivity is higher in the microchannel reactor. Keywords 1) Microchannel reactor 2) CO-PROX 3) CuO x-CeO 2 4) Transient Liquid Phase bonding 5) Al-alloyed ferritic stainless steel

Lecture 6 Interpretation of Batch Reactor Data 6A. Integral Method of Data Analysis At the end of this topic, you should be able to:  Apply the working equations for the ideal batch reactor for simple reactions in determining the rate equation (order and/or rate constant) given experimental data using:

Owing to the water crisis, the development of innovative and clean advanced oxidation processes to decompose a variety of harmful organic compounds in wastewater becomes the main challenge for many research teams. Cold discharge plasma is one of the most widely studied and developed processes, owing to its low energy cost and easy to operate. The impact of different factors on the decontamination effectiveness of discharge plasma are detailed in this review. The generation and reaction mechanisms of reactive species in discharge plasma systems have also gained a significant interest and hence discussed. Several potentials and laboratory-scale reactor design recently reported are discussed and schematically presented. The recent combination of discharge plasma decontamination and other processes in both post and pre-treatment configuration are reported. Some applications of water treatment based on discharge plasma at the pilot scale have been addressing.

Wastewater treatment from dyes of textile industry is a great environmental problem, to which a lot of attention has been given because many of this products used for dying in the textile industry are toxic. Such is de case of azo dyes, most of them are toxic and non-biodegradable and they are discharged to water bodies and channels with no change in there structure and remaining for long periods in the stream. As a pretreatment to this wastewater a coagulation – flocculation process was applied and then a sequenced anaerobic + aerobic + granular activated carbon (GAC), using the last step as a polish treatment. Global COD removal efficiency of 92% was achieved (21% for the anaerobic step, 79% for global anaerobic + aerobic step and 92% for the anaerobic + aerobic + GAC). Related to color removal this had 97% removal efficiency. For BOD5 a 74% removal was achieved for the anaerobic step, and a 89% for the anaerobic + aerobic step and 98% efficiency was achieved for the global proces...

In this paper, a study has been carried out to design a fuel pebble for utilizing thorium in a molten salt cooled and graphite moderated and reflected Innovative High Temperature Reactor (IHTR20MWth). An attempt is made to maximize the conversion of 232 Th to 233 U under the constrain of maintaining negative reactivity coefficient like Fuel Temperature Coefficient (FTC), Coolant Void Reactivity (CVRC) coefficient. This is done by first studying the effect of heavy metal loading and 233 U weight fraction on the infinite multiplication factor by varying the radius of fuel kernel and packing density. The variation of conversion ratio and reactivity coefficients with fuel depletion has also been studied.

Plutonium utilization for a better exploitation of resources is generally a very important aim, especially for Italy which lacks of endogenous resources.
Consequently Italy has pursued this aim utilizing in parallel the two instruments of the most short-term commercialization of
fast breeder reactors and Plutonium recycle in thermal reactors

Evaluación del tratamiento biológico para remoción de color índigo de agua residual industrial textil por un consorcio microbiano en lecho fluidizado Evaluation of the biological treatment for removal of color indigo textile industrial waste water by a microbial consortium in fluidized bed

This study presents an innovative double‐walled borosilicate glass reactor system for the efficient treatment of liquid and gaseous wastewater. This reactor system allows precise temperature control, continuous pH monitoring, and controlled dosing of reagents to optimize reaction conditions. Detailed characterization was carried out by X‐ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), BET (specific surface area) analysis, point of zero charge (PZC), and scanning electron microscopy (SEM) for the SCR, SCRT, and 5%Fe@SCRT materials. For Malachite Green adsorption, SRCT demonstrated a maximum adsorption capacity of 39.78 ± 0.5 mg/g using the Langmuir isotherm model and followed pseudo‐second‐order kinetics. Optimum conditions for adsorption were found to be: an initial concentration of 50 ppm, an adsorbent dosage of 1 g/l, a pH of 8.5, and a temperature of 50°C. For the catalytic oxidation of phenol, 5%Fe@SRCT achieved a remarkable removal rate of 99.9 ± 0.1% under optimum conditions (50 ppm phenol, 1 g/l catalyst dosage, pH 3.5, H 2 O 2 concentration 8.7 mM, and temperature 70°C). Intermediates identified during the reaction included hydroquinone, benzoquinone, catechol, and resorcinol, with degradation occurring over a 60‐minute reaction period. The 5%Fe@SCRT material showed excellent reusability in the removal of phenol by catalytic oxidation, with no significant loss of efficiency over three cycles, while the SRCT underwent three cycles of regeneration for the adsorption of Malachite Green. Scavenger tests confirmed the involvement of hydroxyl radicals in the catalytic oxidation process. In addition, fish survival tests after catalytic oxidation of phenol by 5%Fe@SRCT showed no impact on fish, underlining the environmental safety of this process. In addition, germination tests after decolorization of MG by SRCT demonstrated a good effect with no negative impact, reinforcing the ecological value of this innovative technology. These results highlight the innovative use of SCRT and 5%Fe@SCRT as versatile materials for environmental remediation, exploiting their effective adsorption capacities and efficient catalytic oxidation performance within the proposed double‐walled borosilicate glass reactor system. Practitioner Points The study demonstrates the effectiveness of an innovative reactor system employing SRCT adsorbent and Fe@SRCT catalyst for efficient removal of malachite green and phenol from wastewater. Environmental impact assessment, including seed germination and fish survival evaluation, validates the method's eco‐friendly potential. Implementation of this approach could significantly contribute to sustainable water treatment practices.

Sistem pengubah sampah plastik menjadi bahan bakar minyak adalah proses pengubah plastik dengan cara proses pyrolisis agar menjadi cairan yang nantinya akan menjadi bahan bakar minyak (bbm). Pembuatan alat ini bertujuan untuk mengkonversi limbah plastik menjadi bahan bakar minyak (bbm), mengetahui proses pengolahan sampah plastik dan mengetahui karakteristik bahan bakar yang dihasilkan oleh sampah plastik. rancang bangun alat pengubah sampah plastik menjadi bahan bakar minyak (bbm) terdiri dari beberapa tahap yaitu tahap persiapan berupa studi literatur dan membuat daftar bahan-bahan dan peralatan yang dibutuhkan dalam rancang bangun alatpengubah sampah plastik menjadi bahan bakar minyak (bbm). Tahap selanjutnya dilakukan proses fabrikasi alat, kemudian dilakukan perhitungan terhadap hasil rancangan alat pengubah sampah plastik menjadi bahan bakar minyak (bbm) kemudian melakukan uji fungsional. Dari hasil test labarotorium, minyak plastic yang dihasilkan pada penelitian ini mempunya...

This study investigates the effect the pyrolysis reactor and the condensing system type have on the tyre derived oil (TDO) and DL-limonene yield, as well as benzothiazole concentration in the TDO. All the experiments were performed at 475 ºC and three technologies were investigated, fixed bed reactor (FBR), bubbling fluidised bed reactor (BFBR) and conical spouted bed reactor (CSBR), with the latter being the reactor that provided the highest TDO yield (58.2 wt.%). Furthermore, the CSBR enhances DL-limonene production due to its excellent features (low residence time of volatiles and high heat and mass transfer rates), which minimize secondary cracking reactions. Moreover, in order to maximize the TDO retention efficiency and selectively and reduce the concentration of certain heteroaromatic species, two types of condensation systems were evaluated: tube-and-shell condenser (indirect contact) and a quenching condenser (direct contact). The quenching condenser not only promoted the condensation efficiency for DL-limonene, but also reduced the concentration of benzothiazole in the collected TDO. Indeed, the direct contact between water (fed into the quencher) and the hot volatile stream favours the dissolution of some polar heteroaromatic species, thus reducing the nitrogen and sulphur content in the TDO and increasing the applicability of TDO as fuel.

The design inadequacy of chemical reactor has caused many major accidents in process industries. The absence of safety analysis for chemical reactor especially in the early design stage is one of the reasons for faulty designs. Inherent safety can be used to perform the safety analysis at preliminary design phases. However, the literature is deficient in reporting inherent safety assessment method for chemical reactors. Therefore, this paper introduces a new indexing method for inherently safety assessment of chemical reactors at the preliminary design stage. Chemical Reactors Inherent Safety Index (CRISI) is based on three sub-indices; chemical index, process index and reaction index. These sub-indices are estimated through scores of numerous parameters in each dimension. For the unacceptable score, the process conditions are changed according to the favorable reaction conditions. CRISI is estimated for all combination of process conditions and lowest CRISI value indicates the inherently safer design of the reactor.

Stillage is wastewater from the ethanol industry. Organic matter content in the stillage is quite high, so it can damage to the environment if disposed of directly into the environment. Stillage has great potential to produce biogas that can be converted into energy by anaerobic treatment process. One of the anaeobic digestion methods is the bacterial cell immobilization technique. One of the  reactor types using cell immobilization technique is Anaerobic Fluidizied Bed Reactor (AFBR). This study uses a set of AFBR reactor containing zeolite media with particle diameters of 0.5 - 0.8 mm and operated at a fluidization level (FL) 20% - 40% of the total effective volume of the reactor. This work studied the effect initial organic concentrations and time dring start up process on decomposition of stillage using AFBR. Scope of this work was evaluating AFBR performance  by comparing the matematical model simulation result with experimental data. The simulation results were used as standar...

Carbonation Calcination P CO2 eq, atm Temperature (ºC) Next steps in Ca-looping development: 1.7 MWt pilot plant Facility area Calciner operating under air or oxy-combustion conditions Removable cooling bayonet tubes to change heat extraction in reactors O 2 and CO 2 tanks and gas mixer, to change oxy-combustion ratio Calciner gas heater and indepent steam inyection Gas velocities similar to those found in CFB boilers (3-5 m/s) Next steps: 1.7 MWt pilot plant Complete instrumentation (temperature, pressure, solid samples) FP7 "CaOling" Project: Development of postcombustion CO2 capture with CaO in a large testing facility: www.caoling.eu To advance in the experimental validation of the carbonate looping cycle (at a 1.7 MWt scale range) and demonstrate that this is a low cost, highly energy efficient CO 2 capture technology, suitable for retrofitting coal combustion power plants

Catalytic reduction of CO 2 to produce specialty chemicals or renewable energy sources has attracted immense attention because of the possibility of renewable, sustainable alternative energy, and safer environment. Utilization of CO 2 as an alternative feedstock for synthesis of biorenewable fuel is one of the numerous strategies essential for mitigation of the greenhouse gases emission into the atmosphere. CO 2 reduction occurs at temperature above 413 K and pressure above 1 MPa by using a suitable hydrogenation catalyst. This study investigates the recent advances in catalytic reduction of CO 2 via hydrogenation, focusing on catalysis, reactor, and process intensification. Several factors for the effective catalytic reduction of CO 2 and recent progress in the reactor design for the system are also highlighted.

Ex situ catalytic fast pyrolysis of biomass is a promising route for the production of fungible liquid biofuels. There is significant ongoing research on the design and development of catalysts for this process. However, there are a limited number of studies investigating process configurations and their effects on biorefinery economics. Herein we present a conceptual process design with techno-economic assessment; it includes the production of upgraded bio-oil via fixed bed ex situ catalytic fast pyrolysis followed by final hydroprocessing to hydrocarbon fuel blendstocks. This study builds upon previous work using fluidized bed systems, as detailed in a recent design report led by the National Renewable Energy Laboratory (NREL/ TP-5100-62455); overall yields are assumed to be similar, and are based on enabling future feasibility. Assuming similar yields provides a basis for easy comparison and for studying the impacts of areas of focus in this study, namely, fixed bed reactor configurations and their catalyst development requirements, and the impacts of an inline hot gas filter. A comparison with the fluidized bed system shows that there is potential for higher capital costs and lower catalyst costs in the fixed bed system, leading to comparable overall costs. The key catalyst requirement is to enable the effective transformation of highly oxygenated biomass into hydrocarbons products with properties suitable for blending into current fuels. Potential catalyst materials are discussed, along with their suitability for deoxygenation, hydrogenation and C-C coupling chemistry. This chemistry is necessary during pyrolysis vapor upgrading for improved bio-oil quality, which enables efficient downstream hydroprocessing; C-C coupling helps increase the proportion of diesel/jet fuel range product. One potential benefit of fixed bed upgrading over fluidized bed upgrading is catalyst flexibility, providing greater control over chemistry and product composition. Since this study is based on future projections, the impacts of uncertainties in the underlying assumptions are quantified via sensitivity analysis. This analysis indicates that catalyst researchers should prioritize by: carbon efficiency [ catalyst cost [ catalyst lifetime, after initially testing for basic operational feasibility.

https://www.osti.gov/biblio/4814554
A method is presented by which the spectral information given by spectral index measurements is directly used in order to evaluate an unknown reaction undetectable by activation techniques, In this correlation method no evaluation of the neutron spectrum itself is needed

https://www.osti.gov/biblio/4767101
Differential cross section sets have been evaluated to describe Europium in the thermal and epithermal-fast energy range both as a resonance absorber and as a detector.  The sets have been tested by comparison between calculated and measured reaction rates in the assemblies devised in order to mock up Plutonium by Europium- A correlation method has been used to evaluate the sensitivity of Eu-151 as a spectral index.

Rozdelenie rýchlostných adhéznych konštánt v uhoľnej vzorke Flotation is the process of enrichment which consists in differentiating the useful component (volume property) in the separation products. Flotation leads to the differentiation of the volume property by means of applying the differentiation of surface properties. Since there is a correlation between these properties, the authors determined the distribution of adhesion rate constant in relation with the content of the useful component and applying the dispersive model of a particle. The content of the useful component is directly connected with the volume physical property, represented by particle density. The paper present distribution functions of density and adhesion rate constant in the sample. Also the relation between adhesion rate constant and ash content for narrow density fractions has been revealed.

This work reports the integration of thin (~3e4 mm thick) Pd-based membranes for H 2 separation in a fluidized bed catalytic reactor for ethanol auto-thermal reforming. The performance of a fluidized bed membrane reactor has been investigated from an experimental and numerical point of view. The demonstration of the technology has been carried out over 50 h under reactive conditions using 5 thin Pd-based alumina-supported membranes and a 3 wt%Pt-10 wt%Ni catalyst deposited on a mixed CeO 2 / SiO 2 support. The results have confirmed the feasibility of the concept, in particular the capacity to reach a hydrogen recovery factor up to 70%, while the operation at different fluidization regimes, oxygen-toethanol and steam-to-ethanol ratios, feed pressures and reactor temperatures have been studied. The most critical part of the system is the sealing of the membranes, where most of the gas leakage was detected. A fluidized bed membrane reactor model for ethanol reforming has been developed and validated with the obtained experimental results. The model has been subsequently used to design a small reactor unit for domestic use, showing that 0.45 m 2 membrane area is needed to produce the amount of H 2 required for a 5 kW e PEM fuel-cell based micro-CHP system.

OpenNode is a sophisticated reactor core simulation tool, meticulously designed for educational purposes. Its main function is to solve the complex partial differential equation governing multi-group neutron diffusion in a Cartesian geometry. OpenNode relies on the second- and fourth-order Nodal Expansion Method (NEM) to provide accurate solutions to three-dimensional steady-state problems, encompassing both the direct and adjoint modes. At the heart of this method, the neutron balance equation serves as the fundamental framework for calculating the nodal neutron flux and the effective multiplication factor, enabling the complex evaluation of neutron flux distributions within individual nodes. The NEM methodology, carefully programmed in Fortran-90 in OpenNode, meticulously decomposes the reactor core into nodes of reasonable size. This approach balances computational efficiency and accuracy, achieving outstanding precision even when using a reduced number of computational meshes. To further increase the number of equations while maintaining the balance between unknowns, OpenNode judiciously incorporates two essential approximations: the Weighted Residual Method (WRM) and the Quadratic Transverse Leakage (QTL) approximation. OpenNode transcends simple computational prowess by adopting an intuitive Graphical User Interface (GUI), meticulously developed by combining Python 3, Qt Designer, and Blender software. This Python-powered graphical interface offers users a seamless, user-friendly experience, facilitating tasks such as data entry, execution of complex simulations, calculation of results, data visualization, 3D design of nuclear core geometry, and in-depth analysis of results. One of OpenNode’s key features is its innate flexibility, enabling it to solve problems in both 2D and 3D Cartesian geometries. This adaptability makes it a versatile tool suitable for a wide range of research and power reactor applications, offering users the ability to model and design reactors with unrivaled ease. To substantiate OpenNode’s reliability, comprehensive criticality calculations are carried out in various scenarios, including single-cell verification, BIBLIS, KOEBERG cores in two dimensions (2D), and IAEA cores in three dimensions (3D). The results clearly demonstrate OpenNode’s robustness and reliability in multidimensional criticality analysis. In particular, OpenNode adheres to an open-source philosophy, making it readily available for download. This commitment to open access fosters collaboration and paves the way for wider adoption within the education and research communities, nurturing a thriving ecosystem of shared knowledge and exploration.

This study aimed to determine the parameters needed to design a continuos flow bioreactor. Developing studies that expand the quantity and efficiency of biogas currently produced on an industrial anaerobic wastewater treatment in a food processing plant in the Brazilian State of Goiás. The procedures developed in this work we used nine sets of bioreactors in batch and followed the German Standard VDI 4630. A special workbench was developed for that purpose, alternative procedures for determining the volume of the produced biogas were tested. The biomass studied in this work is the resulting sludge of the wastewater treatment from an industrial plant. The daily production is about nine tons, currently, which is totally discarded. Through this batch tests, it was possible to calculate the volume of biogas production and the ideal biomass retention time of the biomass. Obtained data to project a laboratory continuous flow bioreactor. With this data was made a projection of the biogas production potential by the use of this feedstock in an industrial bioreactor constructed for this purpose.

In the previous chapters we examined the metrological themes of three quintessential Chinese artifacts: the pi disk, the cong, and the ch'ing or music stone. To this list we add another form we regard as comparable in significance: the Mongolian archer's thumb ring. The subject of this study is a particular specimen we have named the #45 because of its numerous associations with the number 45. The story it has to tell resides both in the utility of its form and in the artist's ability to project his impression of the harmony of the cosmos into a work of art. Our objective is to reconstruct a glimpse of that cosmos. Essential to the endeavor is the application of a core set of numbers we call the canon of measure, the lens through which we will contact the deeper aspects of the #45 Thumb Ring.

The effect of zeolite addition in an expanded granular sludge bed anaerobic reactor (EGSB) for the treatment of swine wastewater at high organic loading rates (OLR) was evaluated. The results showed that the presence of the zeolite did not affect the hydrodynamics of the EGSB, adjusting the model of tanks in series. Two reactors (R1 and R2) were operated with effective volume of 3.04 L at 30 ᶱ C. Reactor 1 was operated only with granular sludge while 120 g of zeolite (5 cm of static bed) were added in R2. Theoretical hydraulic retention time (HRT) was 12 hours, obtained with an influent flow rate of 4.0 mL/min. Firstly; an organic load shock (OLS) strategy with constant up-flow velocity (v up ) of 6 m/h for 180 days was evaluated. The evolution of pH, Total Kjeldahl Nitrogen (TKN), Chemical Oxygen Demand (COD) and volatile fatty acids (VFAs) was monitored during the anaerobic digestion process with OSL and the increase of the organic loading rate (OLR). In addition, the microbial co...

This chapter documents the technical development of different generations of nuclear power plants and provides an outlook for possible future concepts and their market prospects. The objective is to assess whether there is really significant technological progress on the horizon and whether these "new" concepts have prospects to become cost-effective. A major conclusion is that most of the so-called Generation IV concepts have already been discussed in the 1950s. At that time, they have not been pursued further due to problems such as costs, limiting factors in material properties and problems in appropriately controlling the fission processes. Yet, since about 2000 a modest revival of the discussion on these concepts is observed, obviously mainly motivated by securing the flow of public money for nuclear research and the broad recognition that with present reactor concepts the nuclear industry will not succeed.

Energy is released when light nuclei fuse to form heavier nuclei. This is the energy which powers stars such as the Sun. The amount of energy released is related to the difference in the masses of the initial and final nuclei according to E = mc 2. Nuclear forces are of short range. Hence reactions occur only when nuclei are in close proximity and to achieve this they must have energy sufficient to overcome their repulsive electrostatic forces. This requires such high temperatures as 15,000,000 K as in the Sun.