The Chinese Journal of Process Engineering

Cover and Contents

The Chinese Journal of Process Engineering. 2025, 25(6): 0.

Asbtract ( )

PDF (3431KB) ( )

Related Articles | Metrics

Advances in direct cooling battery thermal management technology for electric vehicles

Xijiao ZHU Huaxia YAN

The Chinese Journal of Process Engineering. 2025, 25(6): 533-543. DOI: 10.12034/j.issn.1009-606X.224250

Asbtract ( )

HTML ( )

PDF (802KB) ( )

Related Articles | Metrics

With the intensification of the global energy crisis and environmental pollution issues, electric vehicles have become the future trend in automotive power due to their high energy efficiency and low emissions. The heat generated by batteries imposes limitations on their performance. Consequently, it is essential to gain a comprehensive understanding of the factors contributing to this heat generation and to devise and implement effective countermeasures. Addressing these issues is critical for optimizing battery performance and ensuring its safety. This review starts with a brief overview of the factors contributing to battery heat generation. It then delves into direct cooling battery thermal management technology, which utilizes the principle of refrigerant evaporation to absorb and dissipate heat effectively. This approach delivers superior cooling efficiency compared to traditional liquid and air cooling systems. Direct cooling systems are distinguished by their more compact design and faster response times, contributing to more effective thermal management and improved performance. By examining recent literature, this work provides a comprehensive review of the research developments concerning direct cooling systems. It includes an in-depth analysis of the structure design, cold plate design, and optimization strategies for various system parameters. It also highlights how the careful selection of refrigerant properties, along with precise adjustments to system parameters and cold plate configurations, can lead to significant enhancements in temperature uniformity under high-rate charge and discharge conditions. These improvements are crucial for extending the battery's operational lifespan and ensuring its safe and reliable performance. Future research efforts on direct cooling battery thermal management systems should prioritize two key areas: the optimization of the direct cooling plate system's design and parameters, and the development of new, highly efficient, and environmentally friendly refrigerants. Focusing on refining the structural design and operational parameters of direct cooling plates will help improve their performance and adaptability.

Study on residence time distribution characteristics of rotary disk reactor with hydrophilic-hydrophobic alternating structure

Yongqiang FAN Yuqing QIU Dongxiang WANG Caifa LI

The Chinese Journal of Process Engineering. 2025, 25(6): 544-555. DOI: 10.12034/j.issn.1009-606X.224307

Asbtract ( )

HTML ( )

PDF (5807KB) ( )

Related Articles | Metrics

The residence time distribution (RTD) of liquid in the rotary disk reactor with different hydrophilic-hydrophobic surface structures at different rotational speeds and flow rates is studied by pulse tracer method. The results show that the increase of rotational speed and flow rate reduces the dimensionless variance of the smooth disk, narrows the residence time distribution curve, and make the liquid film flow behavior closer to the ideal piston flow. An increase in the number of hydrophobic layer stripes on the disk surface causes the trend of the dimensionless variance value with respect to rotational speed and flow rate to no longer decreases monotonically. Moreover, with the increase of flow rate, the average residence time of liquid in the reactor decreases, and the change of the number of hydrophobic layers on the surface of the turntable also has a certain influence on the average residence time, but there is no significant regularity. In addition, the change of flow rate, rotational speed and the number of hydrophobic layers also affect the flow characteristics and mixing performance of the fluid on the surface of the turntable. The series reactor stage and Peclet number of the smooth disk increases with the increase of flow rate and rotational speed, indicating that the liquid film flow behavior is close to the piston flow. At the same time, the degree of back mixing and dispersion on the surface of the turntable also gradually decreases for smooth disk, while an increase in the number of hydrophobic layer stripes causes the trends of the series reactor stages and Peclet number with respect to rotational speed and flow rate to no longer decreases monotonically. Based on the dimensionless analysis of the related influencing factors of the series reactor stages and Peclet number of different hydrophilic and hydrophobic interphase structures, the prediction correlation of the series reactor stages and Peclet number is established. This study is helpful to further understand the influence of non-uniform infiltration on the liquid residence time distribution and backmixing degree, and provides guidance for the design and optimization of the rotating disk reactor.

Mixing performance analysis of double planetary screw agitator

Yunting HUO Zhong ZHANG Xiaozhong DU

The Chinese Journal of Process Engineering. 2025, 25(6): 556-564. DOI: 10.12034/j.issn.1009-606X.224320

Asbtract ( )

HTML ( )

PDF (4524KB) ( )

Related Articles | Metrics

During the preparation of lithium battery slurry, poor uniformity and powder agglomeration significantly impact battery performance. This study investigates the effects of rotation speed, stirring direction, ratios of impeller diameter to tank diameter, and screw pitch on the flow field distribution, circulation characteristics, shear properties, concentration distribution, and specific mixing energy using computational fluid dynamics (CFD). The results indicate that in counter-rotational stirring mode, the vortex center is notably higher, demonstrating stronger fluid circulation characteristics. The complex vortex structures and cross-flows effectively enhance shear stress. Although specific mixing energy exhibits a positive correlation with impeller speed, counter-rotational stirring exhibits advantages in reducing energy dissipation. Compared to co-rotational stirring, counter-rotational stirring achieves an energy saving rate of 21.7% to 60.7% within the range of 100 to 400 r/min. Regarding mixing uniformity, low-speed co-rotational stirring performs better, while high-speed counter-rotational stirring achieves superior mixing uniformity. Increasing the impeller diameter ratio can effectively boost axial and radial velocities and enhance shear stress, but it also increases specific mixing energy, thereby decreasing mixing efficiency. Increasing pitch enhances axial and radial velocities, improves mixing uniformity, reduces flow resistance, and boosts mixing efficiency. However, excessively large ratios of impeller diameter to tank diameter and impeller pitches can lead to uneven flow and affect the uniform distribution of solid particles.

Influence of furnace and ambient temperature on temperature stress field inside a hydrogen based shaft furnace

Zhengchao HUANG Yan JIN Jiantao QIN Guoqing CAI Hongzhi LING Ziyu LIU Peng LIN

The Chinese Journal of Process Engineering. 2025, 25(6): 565-578. DOI: 10.12034/j.issn.1009-606X.224325

Asbtract ( )

HTML ( )

PDF (5319KB) ( )

Related Articles | Metrics

As a hydrogen metallurgy technology, hydrogen based shaft furnaces have great potential for emission reduction. In response to the temperature field distribution and thermal stress generation in the solid domain of hydrogen based shaft furnaces, this study takes a hydrogen based shaft furnace in a steel plant as the research object. Based on the steady-state thermal and static structure theory, a thermal stress coupling model is established to simulate the heat transfer and thermal stress generation process inside the hydrogen based shaft furnace under different furnace and external temperature conditions. Based on this, the influence of internal and external temperatures on the temperature and thermal stress inside the shaft furnace is studied. The results show that the maximum stress of the furnace shell and refractory material 1 can reach 6150 and 881 MPa respectively, and the internal and external temperatures have a significant impact on the stability of the internal thermal environment and furnace structure of the shaft furnace. The increase in furnace temperature significantly increases the temperature gradient between refractory materials and increases their peak thermal stress. When the furnace temperature is between 800~900℃, the maximum stress increase reaches 93 MPa, and the deformation increase reaches 3.34 mm. The increase in external temperature can reduce the temperature gradient inside and outside, thereby reducing the thermal stress and deformation of internal refractory materials, and reducing the magnitude of stress inside the furnace shell. This study adopts the method of establishing paths at specific locations to visually display the temperature and stress field distributions under different temperature conditions, providing reference for optimizing the stacking method of furnace body materials and structure design of hydrogen based shaft furnaces.

Research on anode copper quality prediction based on MIC feature selection and WOA-LSSVM optimization

Wenzhen XIONG Jianxin XU Ying XIONG

The Chinese Journal of Process Engineering. 2025, 25(6): 579-589. DOI: 10.12034/j.issn.1009-606X.224392

Asbtract ( )

HTML ( )

PDF (3949KB) ( )

Related Articles | Metrics

During the electrolytic copper refining process, the copper content in the anode plate is crucial to the electrolysis efficiency. Fifteen elemental qualities of mixed copper concentrate and crude copper are taken as independent variables, while the copper element quality of the anode plate is considered as the dependent variable. The maximal information coefficient (MIC) was used to analyze the nonlinear correlations among the elements in 54 representative test datasets. The study found that the arsenic (As) content in the mixed copper concentrate and the antimony (Sb) content in the purchased crude copper had the highest correlation with the copper content in the anode plate, with MIC values of approximately 0.8228 and 0.8362, respectively. Based on these findings, a whale optimization algorithm-optimized least squares support vector machine (WOA-LSSVM) regression prediction model was constructed to predict the copper element quality of the anode plate. Experimental results indicated that the WOA-LSSVM model has a high prediction accuracy, with an R2 value reaching 0.9245 and a low root mean square error (RMSE). The prediction accuracy of the WOA-LSSVM hybrid model for anode plate copper content was 4.45% to 123.05% higher than that of other models. Nonlinear analysis methods can effectively capture the complex relationships between different factors in the production process of anode copper. Combining nonlinear analysis methods with machine learning techniques can improve the timeliness and adaptability of anode copper quality control.

Theoretical analysis model for molten steel flow characterization in continuous casting tundish

Yelian ZHOU Zhongkuai JIANG Miaoyong ZHU

The Chinese Journal of Process Engineering. 2025, 25(6): 590-597. DOI: 10.12034/j.issn.1009-606X.224333

Asbtract ( )

HTML ( )

PDF (2584KB) ( )

Related Articles | Metrics

In order to solve the problem of quantitative description for molten steel flow characteristics in multi-strand tundish, the shortage of two traditional analytical models for flowing character multi-strand tundish is investigated in detail. While the number of the tundish strand is more, the parallel model used for flow characteristics of multi-strand tundish occur the phenomenon of the actual residence time is greater than the theoretical residence time. Determining the minimum response time is difficult point for the whole analysis approach studying the flowing character in multi-strand tundish. The existing processing methods for the minimum response induces the calculating plug volume fraction lower than actual one. Meanwhile, based on the hypothesis of combined model, the residence time distribution function for flow characteristics of molten steel in tundish is analyzed. The relationship between the standard variance of the residence time distribution function and the minimum response time is established. Then the standard variance analysis model is proposed to quantitatively describe molten steel flow characterization in tundish. This model adopts the residence time distribution function variance instead of the minimum response time to determine the plug volume fraction of the flow in tundish. Using the average value of the tracer concentration of each strand is equivalent to the overall RTD (Residence Time Distribution) curve. Therefore, the standard deviation of the overall residence time distribution function of the multi-strand tundish is the root mean square average of the one of the residence time distribution function of each strand. In this work, based on the standard variance analysis model, the whole standard variance model is proposed for melton steel flow characterization in the multi-strand tundish. Compared with the traditional multi-strand tundish analysis model, the whole standard variance analysis model used for characterizing the flow fluid in multi-strand tundish not only solves the difficulty of determining the minimum response time for the whole analysis approach, but also avoids the occurrence of negative dead volume with the parallel model. Physical modeling is carried out to study RTD curves in a five-strand tundish, and the reasonability and the excellent feature of the proposed model are verified.

The effect of electric field and physical property parameters on droplet-interface electrocoalescence behaviors

Ran YIN Yan WU Gang LIN Zhaoxue CUI Lining TONG Han WANG Bin LI Zhiqian SUN Zhenbo WANG

The Chinese Journal of Process Engineering. 2025, 25(6): 598-608. DOI: 10.12034/j.issn.1009-606X.224234

Asbtract ( )

HTML ( )

PDF (5757KB) ( )

Related Articles | Metrics

Electrodehydration is an efficient method to solve the difficult crude oil production fluid dehydration problem. Droplet deformation, droplet coalescence, droplet sedimentation and droplet-interface coalescence commonly occur during crude oil electrodehydration. The electric field parameters and physical property parameters have a significant influence on the droplet coalescence efficiency. The droplet-interface electrocoalescence process was investigated using COMSOL Multiphysics software. According to the field conditions of oilfield, the droplet-interface dynamic evolution behaviors were studied by changing the electric field parameters (electric field strength and electric field waveform) and physical property parameters (surface tension, electric conductivity, continuous phase viscosity, droplet size droplet-interface distance). The results showed that the droplet-interface partial coalescence degree increased with increasing electric field strength, droplet size and droplet-interface distance and the droplet-interface complete coalescence occurred at CaE≤5.61, D<0.69D0. The droplet-interface partial coalescence degree decreased with increasing surface tension and continuous phase viscosity, and the droplet-interface complete coalescence occurred at γ*>4.0 and Oh≥0.076. Compared with the DC field, pulsed field with different waveforms can effectively promote droplet-interface coalescence. When σ*≤1.0, with increasing electrical conductivity, the droplet dipole moment increased, and the surface charge movement and transfer speed increased, the dimensionless secondary droplet volume (Vr) increased significantly; When σ*>1.0, the change of droplet dipole moment is small and stable, and Vr gradually decreased, thus the droplet-interface partial coalescence degree first increased and then decreased. The research results provide a theoretical basis and research basis for the design and development of efficient and compact electrodehydration equipment, which has important academic significance and broad application prospect for energy saving, carbon reduction and green low-carbon transformation of oilfield.

Distribution characteristic and enrichment-separation method of valuable elements in waste light emitting diodes

Ling LIU Dongdong SU Binxin DONG Guanghong SHENG Shisheng WANG

The Chinese Journal of Process Engineering. 2025, 25(6): 609-620. DOI: 10.12034/j.issn.1009-606X.224230

Asbtract ( )

HTML ( )

PDF (1544KB) ( )

Related Articles | Metrics

Waste light emitting diode (LED) contains a variety of valuable metal elements, and the recycling of these elements has attracted wide attention. In this work, the distribution characteristics of valuable elements in LED from bulb lamps (L-LED) and SMD 2835 LED (S-LED) were systematically analyzed. XRD, FTIR, ICP-OES, and SEM-EDS methods were used to study the mass composition, phase composition, types of packaging resin and distribution characteristics of valuable metals in the two LEDs. Based on these results, the pre-enrichment and separation of valuable elements in LED using mechanical crushing and screening methods was proposed. The results showed that the lead frames of L-LED and S-LED were pure copper and brass material, respectively. The packaging resins of the two kinds of LED were phenyl methyl silicone resin containing hydroxyl group. The main ingredients of the phosphor in the packaging resin of L-LED and S-LED were Y3Al3.08Ga1.92O12: Ce3+ and Y3Al5O12: Ce3+, respectively. Rare earth elements such as Y, Ce, and Eu existed in the packaging resins, and metal elements such as Cu, Zn, Ni, W, and Ag existed on the metal substrates of lead frames. The scattered element Ga was present only in the chips in S-LED, while it was distributed in both the packaging resin and the chips in L-LED. The components of LED were effectively separated by the processes of mechanical crushing and screening. After crushing and screening, elements Cu, Zn, Ni, W, and Ag were enriched in the screening products with particle size >0.6 mm, and elements Ga, Y, Ce were concentrated in the screening products with particle size <0.6 mm. The pre-treatment process used physical means to enrich and separate valuable elements, which was conducive to the subsequent recovery and utilization of valuable elements.

Electrospun carbon nanofiber membranes for gas diffusion layers in proton exchange membrane fuel cell

Ze YAO Chuang CHEN Feng DUAN Yuping LI Tong QIN Zhengzheng LI Hongbin CAO Dezhi SUN

The Chinese Journal of Process Engineering. 2025, 25(6): 621-634. DOI: 10.12034/j.issn.1009-606X.224328

Asbtract ( )

HTML ( )

PDF (6146KB) ( )

Related Articles | Metrics

In the context of the global energy transition and the increasingly severe environmental issues, proton exchange membrane fuel cell (PEMFC) has attracted widespread attention due to its high efficiency and low emission characteristics. The gas diffusion layer (GDL) plays a vital role in PEMFCs by enhancing gas dispersion, facilitating water and thermal management, and providing mechanical support. However, traditional GDLs suffer from issues such as high brittleness, weak water management capability, and high resistance, all of which can lead to reduced cell performance. This study first prepared multilayer composite polyacrylonitrile (PAN)-based fiber membranes by altering the concentration of the spinning solution and employing sequential electrospinning technology. These fiber membranes were then treated by pre-oxidation and carbonization to obtain PAN-based carbon fiber membranes (CFM). Hydrophobic treatments were performed using two different methods: immersion in 1H,1H,2H,2H-perfluorodecyltrichlorosilane (PFTs) solution or treatment by steam. Comprehensive physicochemical properties of the CFMs were tested, and polarization curves and power density curves of fuel cells were measured. The study results indicated that the proe sizes of CFM fibers in single-layer, double-layer, and triple-layer structures decreased from 0.592 μm to 0.395 μm and 0.317 μm, showing a decreasing trend. Tensile strength peaked at 9.39 MPa in double-layer configurations and dropped to 5.26 MPa in triple-layer configurations. For CFMs with the same number of layers, those prepared with increasing spinning solution concentrations exhibited superior mechanical and electrical performance compared to those prepared with decreasing concentrations. Hydrophobic treatment by immersing in 0.5 g PFTs for 1 hour can significantly enhance the water management capability of the gas diffusion layer (GDL). Compared to single-layer and triple-layer GDLs, the double-layer structured GDL exhibited the highest power density of 0.520 W/cm2. This study provides new methods for the preparation of gas diffusion layers in proton exchange membrane fuel cell.

Preparation and performance study of surface-modified rubber powder/iron tailings-based concrete

Yiming HU Yang HUANG Chao WANG Zhou CHEN Ting YANG Xiangpeng GAO Mingyang LI

The Chinese Journal of Process Engineering. 2025, 25(6): 635-644. DOI: 10.12034/j.issn.1009-606X.224256

Asbtract ( )

HTML ( )

PDF (7310KB) ( )

Related Articles | Metrics

In this study, a new type of construction material, iron tailings-based rubber concrete (ITRC), was innovatively prepared from waste tire rubber powder and iron tailings. The effects of rubber particle size, soaking agent usage, and silane coupling agent grafting on the fluidity, compressive strength, flexural strength, and flexural-compression ratio of ITRC were investigated in depth. The intrinsic mechanism of rubber powder on the improvement of ITRC properties was revealed by advanced analytical techniques such as micromorphology analysis. It was found that pre-soaking of rubber powder in acidic potassium permanganate (KMnO4) solution followed by silane coupling agent treatment significantly improved the compatibility and bonding effect at the interface between the rubber powder and ITRC, and effectively reduced the generation of microcracks in the matrix. Under the condition of an 82∶18 mass ratio of iron tailings to cement, 1wt% rubber powder doping, and an 18% water-to-cement ratio, the 28 day compressive strength of ITRC reached 32.8 MPa, and the flexural strength reached 5.1 MPa, which increased the compressive strength by 28.6% and the flexural strength by 21.4% compared with that of pure iron tailings cement material. This study not only provided a scientific basis for the recycling of iron tailings and waste tires but also provided a new idea for the accelerated recycling of solid waste. The research results helped to promote the development of environmentally friendly building materials, promoted the recycling of resources, and were of great significance in realizing the green transformation of the construction industry. Through this study, it could be seen that waste materials could be transformed into new materials with practical value through scientific methods and innovative technologies, which not only reduced environmental pollution but also opened up a new way for the sustainable use of resources. The successful preparation and optimization of the properties of ITRC demonstrated the possibility of realizing the dual goals of waste utilization and environmental protection in the construction field. This research result had important theoretical and practical value for promoting the sustainable development of the building materials industry.

Table of Content