The Chinese Journal of Process Engineering

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Chin. J. Process Eng.. 2020, 20(2): 0.

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Lattice Boltzmann numerical simulation of flow thermal coupling in porous media with electronic chips

Yue CHEN Ming MA Ying ZHANG Hailong GUO Qikun WAN

Chin. J. Process Eng.. 2020, 20(2): 123-132. DOI: 10.12034/j.issn.1009-606X.219169

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A coupling double-distribution model was developed for simulating natural convection of porous media containing electronic chips based on the lattice Boltzmann method. The effects of different physical parameters on the natural convection of porous media were studied, and the obtained results were compared with the previous literature’s data to verify the feasibility and reliability of the current model. On this basis, effects of the size of the single electronic chip, the layout of the multiple chips, and the surface temperature fluctuation of the single chip on the heat transfer performance of the surface of the electronic chip had been comprehensively investigated. In addition, in order to quantitatively analyze the influence of various parameters on heat dissipation of the electronic chip, the average Nusselt number was employed to evaluate the heat transfer performance, and the following results were obtained: regarding the natural convection inside the porous media with a single chip under a constant temperature boundary condition had a critical chip size at Da=10-2. Under the condition of critical chip size, the distribution of the flow field was quite stronger compared with the case of a chip with a smaller size, but the heat transfer performance was almost the same. When Ra=103, the critical chip size was 0.203125 times the cavity side length, and the critical chip size was 0.25 times the cavity side length at Ra=104. And the critical chip size was 0.390625 times the cavity side length at Ra=105. When the permeability of porous media decreased, the critical chip size did not exist, and the average Nusselt number in the chip surface and the cold wall increased accordingly. For the natural convection occurred in a constant-temperature porous media with multiple-chips, the horizontal arrangement of the chips can present a high heat transfer ratio in the case of porous medium with large permeability (Da=10?2), while for the porous media with small permeability (Da=10?4), the chip layout should be diagonally distributed.

Multi-scale simulation of flow characteristics in selective catalytic reduction honeycomb catalyst

Laiyong WANG Fuping QIAN Jingjing ZHU Naijin HUANG Bing XU Hao WU

Chin. J. Process Eng.. 2020, 20(2): 133-140. DOI: 10.12034/j.issn.1009-606X.219172

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With the development of computational fluid dynamics (CFD) technology, a lot of scholars have applied CFD method and its related software to study the flow characteristics in the selective catalytic reduction (SCR) denitration reactor. However, when using CFD software for numerical calculation, the relevant parameters of the catalyst such as porosity, viscous drag coefficient and the like are usually empirically obtained. Whereas there is no doubt that this method will increase the calculation error. Therefore, in order to improve the denitration efficiency and service life of the catalyst in the SCR denitration reactor, multi-scale numerical study on the flow characteristics of SCR denitration reactor was conducted in this work from both mesoscopic and macroscopic perspectives. At the mesoscopic level, the relationship between the resistance with different catalyst layer thickness and the inlet velocity was studied, and the formula of the resistance was calculated. At the macroscopic level, based on the above relationship, the viscous drag coefficient and the inertia drag coefficient which are required for the macrostructure numerical simulation of the catalyst were calculated. The flow characteristics in the reactor were numerically studied, the numerical results were compared with the experimental data, and the maximum error was 8.6%, which indicated that the multi-scale numerical simulation method proposed was reliable. In addition, the above relationship was also used to the denitration reactor with different structures of catalysts (such as honeycomb and oblique plate), and the calculation results were compared with the data in the literature. The results showed that the trends were consistent and the maximum error was 12.9%, which further demonstrated that the formula obtained in this work had popularization and application value. The research results of this work had certain theoretical and practical value for the structural optimization of SCR denitration reactor.

Determination and calculation of phase equilibrium for N,N′-bis-(2-hydroxypropyl)-piperazine-sodium sulphate?water ternary system

Yating LIU Peng CUI Shaojun JIA

Chin. J. Process Eng.. 2020, 20(2): 141-147. DOI: 10.12034/j.issn.1009-606X.219183

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The solid?liquid equilibrium data of N,N′-bis-(2-hydroxypropyl)-piperazine (HPP)?sodium sulphate?water ternary system were determined by isothermal method at 273.15 and 298.15 K under ambient pressure by wet-residue method. The components of invariant points were determined by XRD and FT-IR analysis. Two isothermal phase diagrams were plotted according to the equilibrium data. There were four crystalline regions in the course of crystallization (pure Na2SO4?10H2O, pure Na2SO4, mixed Na2SO4?10H2O and Na2SO4, mixed Na2SO4 and HPP, respectively) at 298.15 K. Meanwhile, there were three crystallization regions (pure Na2SO4?10H2O, mixed Na2SO4?10H2O and HPP, mixed Na2SO4?10H2O, Na2SO4, HPP, respectively) at 273.15 K. With the decrease of temperature, the crystallization regions of pure Na2SO4?10H2O increased and the solubility of sodium sulfate decreased obviously. The presence of HPP decreased the phase transition temperature between Na2SO4 and Na2SO4?10H2O, resulting in the existence of pure Na2SO4 crystalline region at 298.15 K. But there was not crystallization zone of pure Na2SO4?10H2O at 273.15 K. Moreover, the existence of pure HPP crystalline region had not been found at 273.15 and 298.15 K, that meant if the concentration of HPP was lower than the solubility of HPP in water, HPP would not crystallize in the frozen crystallization process. Furthermore, the modified Pitzer model of single component electrolyte was used to correlate the phase equilibrium data of the system. By means of the solubility data, the Pitzer parameters and solution equilibrium constants of Na2SO4 and Na2SO4?10H2O in the system were calculated by multiple linear regression. Using the Pitzer model to calculate the theoretical data of phase equilibrium, the relative root mean square deviation between the calculated data and the experimental data was no more than 0.0290, which proved that the modified single component electrolyte Pitzer equation can be applied to the calculation of this system.

Numerical simulation of internal flow field and structure improvement of hot air mixer

Juan WANG Jun LI Zhuwei GAO Xingchen HE Shuo ZOU Jiayi WAN

Chin. J. Process Eng.. 2020, 20(2): 148-157. DOI: 10.12034/j.issn.1009-606X.219191

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Hot air mixer is a kind of equipment used in heating and drying system for intermediate cooling treatment. The traditional structure of hot air mixer has the problem of uneven distribution of outlet air temperature in industrial application. For this reason, an improved structure of hot air mixer was proposed in this work. The uniformity of flow field and temperature field distribution in hot air mixer before and after improvement was numerically simulated by using standard k?? model. The results showed that, compared with the traditional structure, the symmetry of flow field distribution in the mixer with symmetrical T double hot air inlet structure was better, and the uniformity of flow field was improved. The reverse flow was greatly improved by the tapered outlet design, and the heat transfer effect was enhanced by adding dispersive baffles. The above three structural improvements could effectively improve the temperature uniformity of the mixer outlet gas flow, reduce energy consumption and improve the thermal mixing efficiency, which had great reference value for the engineering design of the hot air mixer.

Structure optimization of the vertically arranged cooler based on the simulation with discrete element method

Xuekuan ZHANG Ji XU Junjie SUN Yongjie ZHANG Zhenghao ZHANG

Chin. J. Process Eng.. 2020, 20(2): 158-166. DOI: 10.12034/j.issn.1009-606X.219203

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The particle diameter distribution of sinters ore in vertically arranged cooler leads to serious segregation, which will greatly reduce the heat recovery efficiency of vertically arranged cooler. In order to solve the segregation problem of sinters ore, the simulation of the original vertically arranged cooler form domestic steel plant was conducted, which was based on discrete element method with graphics processing unit parallel computing. In the feeding process, the behaviors of sinter ore and their distribution of diameters were studied. The simulation results showed that the difference of movements of particles, which was caused by diameters of different sinters ore, increased with the height of sinters ore dropping from the bunker. Furthermore, larger sinters ore would aggregate in the corners and small sinters ore would aggregate around the point of falling sinters ore, which was due to the lack of internal structures restricting their movements, leading to more serious of segregation happen. Thus, a hopper and the inclined fences were introduced in the top and around the bottom of the storage bin, respectively. The hopper, which turned original design to two-layer storage bin, aimed to reduce the height and tailor the direction of the sinter ore dropping from the bunker, and thus the difference of the velocities and moving behaviors for the sinters ore of different diameters would be reduced greatly. The inclined fence aimed to restrict the movements of the largest sinters ore, so that their aggregation would be reduced. The simulation results of the new structure, including the distribution of the average diameter, the evolution of the segregation and the standard deviation of the average diameter of sinters ore, indicated that the new structure was advantageous in solving the segregation problem of sinters ore in the vertically arranged cooler.

Multi-size simulation of pressure drop in pleated fiber filter media

Jingjing ZHU Fuping QIAN Min WEI Yunlong HAN Jinli LU

Chin. J. Process Eng.. 2020, 20(2): 167-173. DOI: 10.12034/j.issn.1009-606X.219207

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Considering the structural characteristics of fibers, the arrangement of fibers and the number of layers of fibers, the micro-size model of pleated fibers filter media was established based on the control program written by MATLAB, and its solid volume fraction (?) of pleated fibers filter media was calculated. The mathematical correlation between filtration velocity (v) and pressure loss (Δp) of micro-size model was obtained by numerical simulation, and then the viscous drag coefficient (C1) was solved. Based on the above work, a macro-size model of pleated fiber filter media was established, and based on ? and C1 obtained by the micro-size simulation, the mathematical correlation between the face velocity (u) and Δp at macro-size was solved by numerical simulation method, and the mathematical correlation were compared with several empirical formulas. The results showed that the arrangement of the fibers and the thickness of the pleated fiber filter media had an effect on Δp, but had little effect on C1 and other properties. In addition, the properties of pleated fiber filter media obtained at micro-size can provide guidance for macro-size research, and the property parameters of macrostructure can be obtained by using the data obtained from the microstructures. The research results of this study had important theoretical and practical significance for expanding the research methods of fiber filter media and optimizing its structure.

Dissolution of neutralized slag acid leaching substances of coal gangue

Guangya ZHENG Zhengjie CHEN Jupei XIA Weijie WANG Fang GU Yibo SHI Haolin LI Wanlin LI Chenglong LIU

Chin. J. Process Eng.. 2020, 20(2): 174-181. DOI: 10.12034/j.issn.1009-606X.219178

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Coal gangue is a kind of coal-bearing kaolinite associated with coal and a kind of solid waste discharged during coal mining and coal washing. The output of coal resources in our country is huge, so there is a large amount of solid waste emission of coal gangue. The high value-added comprehensive utilization is of great significance to the economy, the environment and the society. The neutralized slag acid leaching substances of coal gangue was used to extract the valuable elements from the acid solution. The effects of dissolution temperature, dissolution time and mass ratio of liquid to solid on the dissolution process of acid solution were researched in this work. Based on the single factor experiment, the dissolution conditions were optimized by these orthogonal experiments. The phase and micro morphology of the neutralized slag acid leaching substances of coal gangue, the acidified product and the acid slag were analyzed by XRD and SEM. The results indicated that the dissolution rates of valuable element oxides were TiO2 82.63%, Fe2O3 96.48%, Al2O3 98.33%, CaO 87.72%, MgO 95.31%, respectively, when dissolution temperature was 80℃, dissolution time was 40 min, mass ratio of liquid to solid was 3:1. Only SiO2 and a small amount of TiO2 were found in acid slag after neutralization residue dissolved. The existence of CaSO4 indicated that the valuable elements in coal gangue and residue acid were fully dissolved through this process. This method had the advantages of short dissolution time, less water consumption and higher dissolution rate of valuable elements in acid leaching system. With this research, it is expected to provide a new approach for the efficient utilization of coal gangue resources.

Catalytic effect of sodium carbonate on the carbothermic reduction of nickel slag

Xiaoming LI Zhenyu WEN Yi LI Weian WANG Xiangdong XING

Chin. J. Process Eng.. 2020, 20(2): 182-188. DOI: 10.12034/j.issn.1009-606X.219187

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Nickel slag, a byproduct come from the nickel flash smelting process, contains a high content of iron and different quantities of valuable metals, such as nickel, copper, cobalt, etc. It is a potential metal resource for the iron and steel industry. The reasonable development and utilization of nickel slag meets the requirements of comprehensive utilization of secondary resources, with environmental, economic, and social benefits. However, nickel slag is difficult to reduce because of its complex mineral composition and containing a lot of fayalite, so catalyzing the reduction of nickel slag to extract valuable metal has become an urgent issue. This work took the nickel slag with total iron content of 39.40wt% and SiO2 content of 32.50wt% as raw materials, the thermodynamic calculation and experimental were carried out with different proportions of sodium carbonate added. The results showed that with the increase of the proportion of sodium carbonate from 0 to 6wt%, the degree of metallization and iron recovery rate of the reduced products increased. The content of sodium carbonate increased to 8wt%, the degree of metallization and recovery rate of iron in the reduced products remained the same or even slightly decreased. The results of SEM showed that the particle size of iron in the reduction product without sodium carbonate added was only 6 μm, and EDS analysis showed that fayalite was abundant. However, the particle size of iron in the reduction product for nickel slag added with 6wt% sodium carbonate was 17 μm, and the content of fayalite was significantly decreased. The diffraction intensity of metallic iron was significantly increased in the XRD pattern. These results indicated that sodium carbonate can promote the reduction of nickel slag and the obtained large size of iron was helpful for subsequent magnetic separation.

Finite element analysis of anti-extrusion strength of machined hole casing

Wei LI Xi CHEN Yang XIA Yumin LI Jian ZHANG Yong XIAO

Chin. J. Process Eng.. 2020, 20(2): 189-196. DOI: 10.12034/j.issn.1009-606X.219186

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The yield strength of the casing directly affects the anti-extrusion performance of the casing. During the processing of casing hole, metal phase transformation may happen in the material near the hole. Thus the yield strength is no longer uniform in the whole casing, which affects the crushing strength of the casing. Taking the P110 casing as an example, the crushing strength of the complete casing and the machined hole casing under the same working conditions were compared. And as a reference group, the influence of the area of the phase transition region and the yield strength of the phase transition region on the crushing strength of the machined hole casing were analyzed. The results showed that the machined hole changed the yield strength of the material, which affected the anti-extrusion performance of the casing. When the yield strength of the metal phase transition region reduced, the extrusion strength of the machined hole reduced, and when the yield strength of the metal phase transition region increased, the extrusion strength of the machined hole increased. And the effect of the phase transition region of the machined hole casing on the extrusion strength of the machined hole casing was gradually weakened with the increase of the yield strength in the phase transition region.

Effects of ammonium perchlorate content on primary combustion performance and aluminum agglomeration of important components ammonium perchlorate/aluminum in aluminum-based fuel-rich propellants

Ying CHEN Yunlan SUN Baozhong ZHU Wei SHI Junchao XU

Chin. J. Process Eng.. 2020, 20(2): 197-204. DOI: 10.12034/j.issn.1009-606X.219193

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The effects of ammonium perchlorate (AP) content on the combustion phenomena, ignition time, combustion diffusion time, burnout time, combustion efficiency, agglomeration phenomena of aluminum (Al) powder as well as the surface morphology and particle size distribution of condensed-phase combustion products in the primary combustion process of AP/Al were studied using a CO2 laser ignition system combined with a high speed photography system, SEM and other analysis techniques related to condensed-phase combustion products. The results showed that the primary combustion process of AP/Al mixture could be divided into three stages: surface ignition stage, combustion diffusion stage and flame extinction stage. However, there were significant differences in the combustion phenomena of each sample in different combustion stages. As the AP content increased from 10wt% to 30wt%, the burning intensity of the sample was enhanced, and the sputtering phenomenon of the solid-phase particles in the combustion process became more and more obvious, the combustion of each sample in the flame extinction stage was mainly changed from the combustion staying at the burning surface of the sample to the combustion of the sputtered particles, and the solid-phase particles that had burned at the burning surface of the sample were first extinguished with increasing the reaction time. The surface ignition time, combustion diffusion time and the combustion duration time decreased, indicating that the combustion reaction rate gradually increased. Meanwhile, as the AP content in the AP/Al sample increased, the combustion efficiency of Al powder increased. Additionally, the particle size of the condensed-phase products also increased, which indicated that the degree of agglomeration increased with the increase of the AP content in the AP/Al sample.

Optimization of iodination reaction for the synthesis of cortisone acetate

Huan LIU Zhengsheng MA Qingfen LIU

Chin. J. Process Eng.. 2020, 20(2): 205-212. DOI: 10.12034/j.issn.1009-606X.219204

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Cortisone acetate is a steroidal drug and an important raw material for the synthesis of steroidal drugs such as prednisone. The preparation of cortisone acetate can be carried out in two steps: iodization and substitution reaction. Iodination reaction is the key step. The maximum molar yield of cortisone acetate was 72.74% in the literature. In this work, the iodization reaction at C-21 position by using 21-deoxycortisone (SSC) as starting raw material and bromine iodine solution as iodinating agent was explored. The conversion of SSC to monoiodide and the exchange between monoiodide and diiodide were studied. The effects of molar ratio of SSC to I2 (bromine iodine solution), feeding rate of bromine iodine solution, extended reaction time and reaction temperature on iodination reaction were investigated. The process was optimized in order to increase the yield of monoiodide. The changes of monoiodide, diiodide and SSC were detected by HPLC. The results showed that there were competition between the conversion of SSC to monoiodide and the continued conversion of monoiodide to diiodide. When the contents of monoiodide and iodinating agent reached certain values, following continuous addition of iodinating agent, the conversion of monoiodide to diiodide became the main reaction, which led to the increase of SSC in the reaction solution. It was also observed that diiodide could be converted to monoiodide during extended reaction process, therefore the yield of monoiodide could be improved. All the studied factors had significant effects on the iodination reaction. The optimized conditions for the synthesis of monoiodide were as follows: molar ratio of SSC to I2 (bromine iodine solution) 1:0.62, feeding rate of bromine iodine solution 0.33 mL/min (SSC 20 g), extended reaction time 120 min, reaction temperature ?3℃. Under these optimal conditions, the molar yield of cortisone acetate reached 87.67%, which was 14.93% higher than the yield of literature reported. This optimized process could provide better economic benefits.

Measurement and correlation of solubility of bucladesine sodium in water-acetone mixed solvent

Binghui WEI Jiucheng WANG Feng GAO

Chin. J. Process Eng.. 2020, 20(2): 213-221. DOI: 10.12034/j.issn.1009-606X.219206

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The molar solubility of bucladesine sodium in water?acetone mixed solvent was measured by High Performance Liquid Chromatography (HPLC) at atmospheric pressure and temperature of 278.15?298.15 K. Moreover, the modified Apelblat, λh and C/R?K models were used to correlate and analyze the experimental solubility data of bucladesine sodium. The thermodynamic properties of bucladesine sodium dissolution process, including the changes of enthalpy, entropy and Gibbs free energy, were calculated based on modified Apelblat model. Furthermore, the molar solubility difference between bucladesine sodium and two related impurities (sodium N6-butyryladenosine-3',5'-cyclic phosphate and sodium 2′-O-butyryladenosine-3',5'-cyclic phosphate) in mixed solvent was determined as the molar fraction of acetone was 0.7110～1.0000. The results showed that the molar solubility of bucladesine sodium in mixed solvent increased as the temperature increased. With increasing molar fraction of acetone, the molar solubility of bucladesine sodium increased to the maximum and then decreased, which could be explained by cosolvent phenomenon. When the molar fraction of acetone was 0.4220, the molar solubility of bucladesine sodium was the largest. It was found that the three models showed good correlation effect with low relative average deviation (RAD) and root-mean-square deviation (RMSD) values which demonstrated that the correlated values were in good agreement with the experimental values throughout the entire range of temperature and tested molar fraction of acetone. The change of enthalpy of dissolution process was positive while the change of Gibbs free energy was negative, which indicated that the dissolution process of bucladesine sodium in mixed solvent was a spontaneous endothermic process. The molar solubilities of bucladesine sodium and two related impurities increased with increasing temperature and decreased with increasing molar fraction of acetone, but there was a significant difference between the molar solubility of bucladesine sodium and two related impurities as the molar fraction of acetone increased from 0.7110 to 0.8538. The above solubility characteristics of bucladesine sodium and two related impurities could be used as the basic data for further study in bucladesine sodium crystallization process.

Growth process of CO₂ bubbles on calcite surface in sulfuric acid solution

Lin MA Rongdong DENG Dingquan XING Hongxi CHEN Xingying FAN Tingyi HUANG

Chin. J. Process Eng.. 2020, 20(2): 222-229. DOI: 10.12034/j.issn.1009-606X.219305

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Calcite is one of the most common gangue minerals in mineral processing. The efficient separation of calcite from valuable minerals has long been a focus and challenge in the field of mineral processing, and especially in the processing of calcium-containing minerals such as scheelite, fluorite, and apatite. In acidic pulp, calcite could react with hydrogen ions to form CO2 bubbles, which are sometimes beneficial for minerals separation. The process of CO2 bubble generation by the reaction between calcite and sulfuric acid was systematically studied using high-speed camera in this work. The effect of sulfuric acid concentration and calcite particle size on CO2 bubbles production, bubble growth rate, detachment diameter, quantity distribution, apparent specific gravity of calcite particles and surface morphology after reaction of calcite with sulfuric acid were investigated. When calcite encountered acid, CO2 bubbles generated immediately on the surface of calcite. Once grew to a certain size, these bubbles would detach quickly from the calcite surface. When sulfuric acid concentration was in the range of 1.0wt%?2.0wt%, CO2 bubbles production on the calcite surface was inversely proportional to sulfuric acid concentration. The higher the concentration, the less CO2 bubbles was produced, and the faster the reaction terminated. As sulfuric acid concentration increased, the bubble growth rate increased and the detachment diameter reduced. The surface of the calcite would always adsorb CO2 bubbles during the reaction time, resulting in a smaller apparent weight of calcite and the change of surface properties of calcite. Calcium sulfate crystals were formed by the reaction of calcite with sulfuric acid, which prevented the further reaction of calcite with acid. The apparent specific gravity of calcite varied with the particle size, but only at small values of 6?7 seconds. The research of this work provided a fundamental basis for the separation of calcite from other non-carbonate minerals.

Performance and mechanism of ozonation of bisphenol A

Jiaoyu CHEN Guanhua MENG Wang WEI Baohe LIU Suyun DING Jiarui HE

Chin. J. Process Eng.. 2020, 20(2): 230-236. DOI: 10.12034/j.issn.1009-606X.219165

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The wide application of bisphenol A (BPA) affects all aspects of human life, and bisphenol A has potential harm to human health. Ozonation has a rapid rate of reaction in the degradation of organic pollutants and no secondary pollution. In this work, the degradation of bisphenol A in aqueous solution by continuous ozone from the ozone generator was studied. The effects of ozone concentration, influent flow rate, pH, initial concentration of bisphenol A and temperature on the ozonation of BPA were investigated. And the reaction mechanism of ozonation of bisphenol A was explored. The results showed that ozonation had a good removal effect on bisphenol A from contaminated water. The conditions for ozonation of bisphenol A were obtained by ozone concentration of 11.04 mg/L, flow rate of 2 mL/min, raw water pH at 6.83, loaded temperature 40℃, initial concentration of bisphenol A 10 mg/L, the removal rate of bisphenol A reached up to 86.12%. Appropriate temperature rise promoted ozone degradation of bisphenol A and increase the removal rate of bisphenol A. The appropriate increase of ozone dosage increased the removal rate of bisphenol A. Ozonation of bisphenol A was a rapid reaction with low activation energy. The increase of pH reduced the removal rate of bisphenol A, and ozone degradation of bisphenol A was better under acidic conditions. The removal rate of bisphenol A decreased with the increase of flow rate. When the ozone dose was constant, the increase of initial concentration of bisphenol A resulted in a decrease of the removal rate of bisphenol A. Tert-butanol inhibited the production of hydroxyl radicals and reduced the removal rate of bisphenol A, but its concentration had little effect on the removal rate of bisphenol A. Ozonatio of bisphenol A was mainly caused by direct oxidation of ozone and there was also indirect oxidation of hydroxyl radicals.

Study on characteristics of hydrogen fuel cell power generation system using metal hydride as solid-state hydrogen source

Hongli YAN Zuowei LU Zhiliang JING Zhen WU

Chin. J. Process Eng.. 2020, 20(2): 237-244. DOI: 10.12034/j.issn.1009-606X.219173

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The hydrogen fuel cell technology has been increasingly developed in recent years due to its advantages of clean utilization, high efficiency and free-pollution. Thus, hydrogen fuel cell technology is regarded as one of the most promising power generation systems in the future. In the practical applications of hydrogen fuel cell technology, an efficient, safe and economical hydrogen storage method is remarkably crucial for promoting large-scale utilization of hydrogen fuel cell technology. Among all the hydrogen storage methods, the solid-state hydrogen storage method has been extensively reported to be the promising candidate for hydrogen storage due to its advantages of high hydrogen storage capacity, good hydrogen absorption/desorption reversibility, moderate hydrogen absorption/desorption plateau pressure, low price and good safety. Metal hydride, as the well-known hydrogen storage material, has been successfully applied in the fields of heat pump, hydrogen compression and polygeneration. In this work, the solid-state hydrogen storage reactor based on metal hydride was designed and integrated with the proton exchange membrane fuel cell (PEMFC) to form a highly efficient and high volumetric density power generation system. Specifically, an experimental platform of the fuel cell power system with a nominal output power of 20 W was developed and used to investigate the effects of various key operating parameters including hydrogen absorption pressure, dehydriding temperature and the hydrogen flow rate after dehydriding on the hydrogen fuel cell system?s output. The results showed that a stable hydrogen flow rate after dehydriding could be maintained for up to 4500 s when the hydrogen absorption pressure was at least 0.60 MPa. Moreover, a higher hydrogen flow rate resulted in higher power generation from the fuel cell power generation system. When the dehydriding temperature was more than 60℃, the metal hydride hydrogen storage reactor enabled a complete release of the stored hydrogen. However, further increased in the dehydriding temperature had little contributions to facilitating the dehydriding reaction. In addition, lower hydrogen flow rates which were still over the required flow input into the PEMFC resulted in longer working time of the fuel cell power generation system.

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