New Type Of Reactor Research Articles

Study on the synthesis of nanoparticles and their power characteristics in a bubble liquid membrane reactor

Abstract A bubble liquid film reactor is a new type of reactor used for preparing nanoparticles, which has strong inflation ability and dispersion, homogenization, and emulsification effects, especially suitable for preparing loose nanoparticles. In the actual production of enterprises, there is an urgent need to expand production capacity and scale up the reactor. Due to the lack of power characteristic data during the reaction process, it is difficult to select the motor, resulting in unnecessary energy and cost waste. Therefore, the power characteristic data of bubble liquid film reactors urgently needs to be studied. This article investigates the influence of operating conditions such as bubble cap diameter and immersion depth on stirring power and obtains the power characteristics during the operation of a bubble liquid film reactor. The results indicate that the larger the diameter of the bubble cap disk, the stronger the power consumption, but the smaller the power input capacity. The deeper the immersion depth, the higher the power consumption and the stronger the power input capability. Finally, fitting the dimensionless power standard formula provides a mathematical model for reactor amplification, providing theoretical guidance for enterprises to expand production lines and increase production capacity, and providing data support for motor selection.

Anammox process in anaerobic baffled biofilm reactors with columnar packings: Characteristics of flow field and microbial community

The enrichment of anammox bacteria is a key issue in the application of anammox processes. A new type of reactor － anaerobic baffle biofilm reactor (ABBR) developed from anaerobic baffle reactor (ABR) was filled with columnar packings and established for effective enrichment of anammox bacteria. The flow field analysis showed that, compared with ABR, ABBR narrowed the dead zone so as to improve the substrate transferring performances. Two ABBRs with different types of columnar packings (Packings 1 and Packings 2) were constructed to culture anammox biofilms. Packings 1 consisted of the single-form honeycomb carriers while Packings 2 was modular composite packings consisting of non-woven fabric and honeycomb carriers. The effects of different types of columnar packings on microbial community and nitrogen removal were studied. The ABBR filled with Packings 2 had a higher retention rate of biomass than the ABBR filled with Packings 1, making the anammox start-up period be shortened by 21.28%. The enrichment of anammox bacteria were achieved and the dominant anammox bacteria were Candidatus Brocadia in both R1 and R2. However, there were four genera of anammox bacteria in R2 and one genus of anammox bacteria in R1, and the cell density of anammox bacteria in R2 was 95% higher than that in R1. R2 has the advantage of maintaining excellent and stable nitrogen removal performance at high nitrogen loading rate. The results revealed that the packings composed of two types of carriers may have a better enrichment effect on anammox bacteria. This study is of great significance for the rapid enrichment of anammox bacteria and the technical promotion of anammox process.

Deep learning to design Z-FFR device models

Z-Pinch fusion centre, encased by a fission envelope, serves as an individual neutron source. It can expeditiously catalyze fission reactions in 238U and 232Th nuclear materials, which are hard to use in current commercial nuclear reactors. This is the essence of the Z-Pinch Driven Fusion-Fission Hybrid Reactor (Z-FFR). The fusion core acts as a stand-alone neutron source, efficiently driving fission reactions in nuclear energy materials that are difficult to use in existing commercial nuclear reactors, such as 238U and 232Th. Then it can deliver enormous amounts of energy in a stable and controlled manner. This new type of reactor uses the fact that the fission discharges energy (∼200 Megaelectronvolts) and the neutrons’ number released is much greater than that released when the fusion discharge energy (∼17 Megaelectronvolts). Moreover, the neutrons’ number is released to achieve energy amplification and neutron amplification, significantly makes it less difficult in implementing fusion technology applications, and increases the utilisation of nuclear energy resources by more than one order of magnitude. The Z-FFR has a complex design and covers a wide range of physical processes. The use of deep learning to design the device model allows for a more closely engineered model. Deep learning allows the model design to be decomposed, the Z-FFR design data flow to be analysed and optimised, and the tedious physical process to be turned into a deep learning network layering so that we can obtain an accurate physical model. The deuterium-tritium combustion depth parameters obtained by deep learning reach around 30%, demonstrating the ability to achieve fusion self-sustained combustion.

THE FUTURE OF ATOMIС ENERGY IN UKRAINE FROM THE POSITION OF THE DEVELOPMENT OF A LOW-СARBON EСONOMY

This article studies the future development of the energy industry with the aim of reducing greenhouse gas emissions. Three different options for planning the use of electricity-generating enterprises and determining the most optimal for the environment and economy of the country based on graphs of the dynamics of greenhouse gas emissions into the atmosphere are considered. The assessment and selection of the most optimal option is based on the Low-Carbon Development Strategy of Ukraine.
 The types of electricity generation that most pollute the environment and those that practically do not pollute have been determined. The share of produced electricity accounted for by each type of generation and the dynamics of electricity production in recent years were considered in percentage terms. Also, this article provides an example of one of the countries abandoning nuclear energy, and what consequences this had for the energy balance and the development of a low-carbon economy. The most appropriate option for the development of power plants in Ukraine was determined and it was considered how in the future it is possible to increase the share of electricity produced at nuclear power plants and reduce the share of electricity produced at thermal power plants. The development of nuclear energy has a positive effect on the country's energy independence, so it must be developed and, if possible, switched to new types of reactors in order to make energy even more secure.

Numerical investigation of thermal stress in the fuel element of high-temperature air-cooled nuclear reactor

The direct-cycle nuclear reactor cooled by the air can be adopted in the aircraft of near space. The operation conditions are with high temperature and heat flux which can lead to the generation of thermal stress and result in the crack of the fuel element. To confirm the effect of air parameters and heating conditions caused by nuclear reactor on the thermal stress of the new type of reactor, the numerical investigation based on the multi-physics coupling method is conducted. Firstly, the boundaries and main physical properties of the fuel element are determined. Subsequently, the coupled methods of Computational Fluid Dynamics and Computational Structural Mechanics are adopted after being validated. Afterwards, the effects of cosine heating, heat flux, inlet temperature and pressure on thermal stress of the fuel element are investigated. The results reveal that the position with maximum thermal stress is close to the position with maximum heat flux. The condition with low heat flux can be adopted to obtain the sketchy thermal stress under high heat flux conditions ranging from 221 kW/m2 to 1.013 MW/m2 before the crack of the fuel element. The effect of the inlet temperature on thermal stress can be ignored compared with the heat flux. The effect of pressure on thermal stress is limited, but higher pressure is recommended. The research can lay the basis for the design of the reactor cooled by air.

Research on Mixing Behavior in a Combined Top–Bottom–Side Blown Iron Bath Gasifier

The iron bath gasifier studied in this paper is a new type of reactor for handling organic solid waste, in which the complex transport phenomena comprising high temperature, the multiphase flow, mixing, and chemical reaction takes place. It is of great significance to study the melt’s flow and mass transfer behavior in this reactor. The influence of different process parameters on the mixing behavior of the molten pool was studied by the water modeling experiment and numerical simulation method. The experimental results show that the height of the water phase has a highly significant effect on the mixing time of the molten pool, followed by the horizontal angle of the side gun and the bottom blowing flow rate. As the height of the water increases, the mixing time decreases. When the horizontal angle of side lances increases, the mixing time decreases. With the increase in the flow rate of the bottom lance, the mixing time decreases. The results obtained by numerical simulation were compared with the experimental results to determine the reliability of the mathematical model for future optimization of the process parameters by numerical simulation. These studies are helpful for optimizing the design of the reactor and improving the process parameters.

Core design optimization of small modular dual fluid reactor based on NSGA-III in the aspect of reactor physics

With a small molten salt lead-based reactor as its research object, this paper proposes a method combining Monte Carlo techniques and advanced optimization algorithms to realize the optimal design of the core. By selecting different core parameters and applying a multi-objective genetic algorithm, a more compact core design is achieved. Calculation results show that the proposed method can optimize the structure of a small molten salt lead-based reactor, realize the core optimization design under multi-objective constraints. The developed method can provide a favourable reference for the development and design of a new type of reactor.

Characterization of a novel micro-pressure double-cycle reactor for low temperature municipal wastewater treatment

ABSTRACT To solve the deterioration of effluent caused by low temperature in urban sewage treatment plant in cold areas, a new type of reactor was proposed, the biochemical environmental and low-temperature operating characteristics of the reactor were studied. Through analysis of flow simulation and dissolved oxygen (DO) distribution when the aeration rate was 0.6 m3/h, it showed that there were many different DO environments in the reactor at the same time, which provided favourable conditions for various biochemical reactions. The operation test showed that the average effluent removal rate of COD, TN, NH4 +-N and TP was 92.53%, 74.57%, 89.61% and 96.04%, respectively. And there were a variety of functional bacteria related to nitrogen and phosphorus removal in the system, most of them with strong adaptability at low temperatures. Among the dominant microorganisms, Flavobacterium and Rhodobacter were related to denitrification, Aeromonas and Thiothrix were related to phosphorous removal. Denitrifying phosphorus removal was the main way of phosphorus removal. Picrust2 results showed that the reactor operated well at low temperature, and the regional difference distribution of nitrification genes further confirmed the existence of functional zones in the reactor. The results showed that the Micro-pressure Double-cycle reactor worked well at low temperature, which provided a new idea and way for the upgrading of urban sewage treatment plants in cold areas.

Hydrogen Storage by Reduction of CO₂ to Synthetic Hydrocarbons.

The storage of renewable energy is crucial for the substitution of fossil fuels with renewable energy. Hydrogen is the first step in the conversion of electricity from renewable sources to an energy carrier. However, hydrogen is technically and economically challenging to store, but can be converted with CO₂ from the atmosphere or oceans to hydrocarbons. The heterogeneously catalyzed gas phase reaction and the electrochemical CO₂ reduction are reviewed and the application of a new type of reactor is described. The mechanism of the gas phase CO₂ reduction on a heterogeneous catalyst is shown in detail and the function of the supported catalyst is explained. Finally, an economic estimation on the cost of synthetic methane is presented which leads to a cost of 0.3 CHF/kWh in CH₄.

Advances in acrylamide bioproduction catalyzed with Rhodococcus cells harboring nitrile hydratase.

Acrylamide is an important bulk chemical used for producing polyacrylamide, which is widely applied in diverse fields, such as enhanced oil recovery and water treatment. Acrylamide production with a superior biocatalyst, free-resting Rhodococcus cells containing nitrile hydratase (NHase), has been proven to be simple but effective, thereby becoming the main method adopted in industry to date. Under the harsh industrial conditions, however, NHase-containing Rhodococcus cells in a natural state are prone to deactivation. Thus, multiple genetic strategies able to evolve recombinant Rhodococcus biocatalysts at either the enzyme or cell level have been reported. While most of the methods on enzyme engineering concentrate on NHase stability enhancement by strengthening the flexible sites, Rhodococcus cell engineering with various methods can enhance both the NHase activity and stability as well. Developing some new types of reactors, especially the microreactor, is also an effective way to improve the hydration process efficiency. Compared with the conventional stirred tank reactor, the membrane dispersion microreactor can enhance the heat and mass transfer in the hydration process with Rhodococcus cells as biocatalysts, thereby significantly improving the productivity of the acrylamide bioproduction process.

A new forward-impinging-back reactor for the scale-up of partially decoupled oxidation of ethane to produce ethylene and acetylene

Ethane in unconventional natural gas was mainly used as the feedstock of the steam cracking process. In our previous work, a new ethane conversion process named partially decoupled process (PDP) was proposed and investigated by experiments and numerical simulations. In the ethane PDP, coke oven gas or other cheap gas combusts with stoichiometric oxygen as heat carrier, and ethane is mixed with the heat carrier and cracked at a high temperature. In this work, a new type of reactor named Forward-Impinging-Back (FIB) reactor was proposed for a better scale-up performance and investigated by CFD simulations coupled with a detailed reaction mechanism. The simulation results showed that a maximum C2 (C2H2 + C2H4) yield of 65.6% was obtained for the ethane PDP in a FIB reactor. The FIB reactor and Jet-In-Cross-Flow (JICF) reactor of small diameter had similar performance. When the reactor diameter increased from 30 mm to 390 mm, the C2 yield maintained at 64% in the FIB reactor, but decreased from 64.4% to 43.8% in JICF reactor.

Perimetric Distributed UV Reactor and Its Validation and the Decontamination of Fresh Broccolis

The ultraviolet (UV) irradiation as a non-thermal processing technique for microbial decontamination of food (MDF) has been the gainer in many variations after the inclusion of UV light as an alternative for MDF by the US FDA. However the lasts years increase the application of the UV light in food, water and pharmaceutical utilization. In this report, we describe a new type of reactor, where the UV emitters are parametrically distributed for decontaminating fresh broccolis. We described the constructed reactor and its characterization with the validation of the system with controlled contaminated broccolis. The overall liquid was contamined with 105 UFC/mL E. coli operating with a flow rate of 80 L/min in 30 L and six lamps in the reactor and the collection of samples in intervals of 25 min. The E. coli used in this experiment was eliminated in 99,99% The intensity of UVC light distributed in the internal part of the reactor is practically homogeneous due to the developed geometry. The kinetics of microbial death presented no great influence on this variation. That is, any volume of water contained in the process can be decontaminated. A relation between UV and the flow rate was stablished. The system demonstrated its capacity in inactivating the microorganism.

Preparation and co-dispersion of TiO2-Y2O3 suspensions through the study of their rheological and electrokinetic properties

The development of Generation IV sodium-cooled fast reactors (SFR) is currently studied by several countries, France in particular. To manufacture the UO2-PuO2 fuels for these new types of reactors, new innovative wet colloidal processing routes are investigated. Among these wet colloidal processes, some involve at first the preparation of high solid content water-based suspensions. This key step needs to be investigated in order to obtain highly and easily processable suspensions, featuring optimal viscosity and dispersion state. The structures and properties for all intermediate and final products involved in such ceramic manufacturing processes are heavily affected by these suspension characteristics. Therefore, they are critical to ensure a compliant final product (i.e. fuel pellets) with the required density, homogeneity, mechanical strength and absence of defects. In this scope, preparation process of such suspensions was developed by the use of UO2 and PuO2 surrogating (i.e. mimicking) powders, TiO2 and Y2O3 respectively.

Experimental–Industrial Operation of RZhFA-6500 Reactors As Part of a Two-Link Smoothing Filter Device

Two blocks were commissioned of an RZhFA-6500 reactor as part of the two-link smoothing device at the Letnaya traction substation of the Sverdlovsk Railroad. To test the efficiency of the reactor, a forced short circuit experiment was performed without stopping the movement of the electric vehicle over the section, the level of psophometric voltage on the dc buses of the traction substation was measured and an experiment was carried out of a forced short circuit with cessation of movement over the section. During the experiments, oscillograms of transient processes were taken, analysis of which confirmed the efficiency of the new type of reactor in the structure of a two-link filter device.

A review on efficiency and cost effectiveness of electro- and bio-electro-Fenton processes: Application to the treatment of pharmaceutical pollutants in water

Nowadays, the treatment of wastewater is a worldwide concern due to the large impact on the environment and human health. Among different types of pollutant, pharmaceuticals are increasingly of emerging concern, as they are generally resistant to the conventional treatment methods and harmful to the environment. Advanced oxidation processes and especially electrochemical advanced oxidation processes (EAOPs) constitute an efficient way to eliminate this kind of pollutants. Among them, the electro-Fenton (EF) process is an environmentally friendly EAOP particularly efficient to remove persistent/toxic pollutant from the water. The main drawback of this method, however, is the relatively high cost due to the energy consumption when a complete mineralization of treated solutions is required. To reduce electrical energy consumption, the combination with a biological treatment was suggested as shown by several successful studies. This review is first addressing ways to improve the degradation efficiency and to reduce the cost of the EF process, with a focus on new types of reactors: especially geometrical modifications, change of the out streaming or the O2 supply. The continuous process is then taken into consideration in order to enable scaling-up. Secondly, the combination of the EF process with a biological treatment for efficient removal of pharmaceuticals is overviewed with focus on the cost, the treatment efficiency and the order (pre- or post-) of treatment. The efficiency of such a system is clearly demonstrated.

Novel Ebullated Bed Residue Hydrocracking Process

Residue hydrocracking has been attracting more and more attention to the refining industry in recent years, and one of the best approaches is ebullated bed residue hydrocracking (EBRH). STRONG ebullated bed residue hydrocracking uses a new type of reactor, and a 50 KTA demonstration unit has been put into operation now. Crucial points of STRONG residue hydrocracking are proposed physical and chemical properties of a solid catalyst, flow mechanism, efficient separation of gas–liquid–solid in the reactor, and reaction performance within various scales of the pilot tests. The results showed that the STRONG reactor with a microspherical catalyst inside a canceled recycling pump inside and outside overcame mass transfer difficulties, solved diffusion control problems, and created high catalyst efficiency to reduce catalyst consumption. To prevent the catalyst from being entrained from the reactor, a triphase separator was used and the amount of catalyst carried off was less than 1 μg/g.

Anaerobic Treatment of Wastewater in Colder Climates Using UASB Reactor and Anaerobic Membrane Bioreactor

Direct anaerobic treatment in the main line of a wastewater treatment plant is a promising way of recovering chemical energy, even in moderate climates. Full-scale applications of upflow anaerobic sludge blanket (UASB) reactors are common in warm climates and have recently begun to appear in areas with colder climate. Several new types of reactors optimized for low temperature treatment were proposed such as UASB-Digester or anaerobic membrane bioreactor (AnMBR). However, long-term operation of such systems treating real wastewater at winter temperatures is needed to assess their suitability. The aim of this article is to evaluate the operation of a laboratory-scale UASB reactor (1.9 L) before and after the installation of ultrafiltration membrane for solids separation from the effluent. The laboratory model treated wastewater at 15°C for over 850 days. The organic loading rate of the UASB reactor and AnMBR was 1.4 and 1.6 g COD/[L·d], respectively, while the hydraulic retention time was around 9 and 10 h. Energy recovery from the wastewater in gaseous methane was 4% and 6% in the UASB reactor and AnMBR, respectively. The methane content was 63% ± 17% and 64% ± 2%, respectively. In the UASB reactor, 64% of the influent chemical oxygen demand (COD) was removed in long term. The AnMBR ran at average 85% COD removal. Results show that AnMBR can deliver more stable effluent quality for wastewater treatment even at low (15°C) temperature. However, even the AnMBR effluent requires further posttreatment. Thus, simpler and less energy demanding UASB appears more relevant for wastewater pretreatment under European conditions.

Preparation and Photocatalytic Performance of MWCNTs/TiO2Nanocomposites for Degradation of Aqueous Substrate

In this study, multiwalled carbon nanotubes (MWCNTs)/TiO2nanocomposites were obtained by constant volumetric wet impregnation processes. The prepared catalysts were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The effect of reaction conditions on photocatalytic performance of the catalysts was investigated by the degradation of methyl orange (MO) under UV irradiation, in a new type of reactor with unique structure. The results showed that the prepared nanocomposite exhibited higher MO degradation efficiency than that of pure nano-TiO2. Besides, in batch experiments of influencing factors, including ionic strength, oxidant amount, and response times, the presence of H2O2would contribute to increasing the MO degradation rate of MWCNTs/TiO2samples. Ionic concentration and long reaction times are adverse to the MO degradation in the processes.

Decomposition of atrazine traces in water by combination of non-thermal electrical discharge and adsorption on nanofiber membrane

In recent decades, several types of persistent substances are detected in the aquatic environment at very low concentrations. Unfortunately, conventional water treatment processes are not able to remove these micropollutants. As such, advanced treatment methods are required to meet both current and anticipated maximally allowed concentrations. Plasma discharge in contact with water is a promising new technology, since it produces a wide spectrum of oxidizing species. In this study, a new type of reactor is tested, in which decomposition by atmospheric pulsed direct barrier discharge (pDBD) plasma is combined with micropollutant adsorption on a nanofiber polyamide membrane. Atrazine is chosen as model micropollutant with an initial concentration of 30 μg/L. While the H2O2 and O3 production in the reactor is not influenced by the presence of the membrane, there is a significant increase in atrazine decomposition when the membrane is added. With membrane, 85% atrazine removal can be obtained in comparison to only 61% removal without membrane, at the same experimental parameters. The by-products of atrazine decomposition identified by HPLC-MS are deethylatrazine and ammelide. Formation of these by-products is more pronounced when the membrane is added. These results indicate the synergetic effect of plasma discharge and pollutant adsorption, which is attractive for future applications of water treatment.

Verification of SAMG entry condition for APR1400

The entry condition of the Severe Accident Management Guideline (SAMG) for APR1400 has been evaluated on the basis of the Core Exit Temperature (CET) and Peak Cladding Temperature (PCT) calculated by the MARS-KS code. Although the APR1400 is a new type of reactor in Korea, it has been used the same entry condition to the SAMG as the former version of reactor. This study models the APR1400 with a system analysis code, i.e., the MARS-KS code. Then three initiating events which contribute 80 percent to the Core Damage Frequency (CDF) are selected as reference accidents to figure out the validity of the entry condition: Station Black-Out (SBO), Small- and Medium-Break Loss-Of-Coolant-Accidents (SBLOCA and MBLOCA). In order to verify the SAMG entry condition, the times to three important points, i.e., the current SAMG entry point (CET 923K), effective transition point, and fuel damage point (PCT 1255K) have been compared for each scenario. The conclusion reveals that the current SAMG entry condition properly indicates the fuel damage point and effective transition point for the events.