Operational Parameters Research Articles

Construction of energy consumption monitoring system for energy saving equipment in seawater desalination based on whale algorithm

ABSTRACT Seawater desalination has emerged as a pivotal solution to address freshwater scarcity in coastal regions, with China being a prominent adopter of this technology. This paper compares three large-scale seawater desalination projects in China: the Six Heng Water Treatment Plant, the Caofeidian Desalination Project, and the Huaihai Yu Huan Power Plant Desalination Project. Each project employs distinct desalination technologies, including reverse osmosis and dual-membrane processes. We evaluate these systems’ operational parameters, performance indicators, and cost-effectiveness over their operational lifespans. Key considerations include seawater intake, pretreatment processes, reverse osmosis desalination, energy recovery systems, and post-treatment mineralisation. The analysis highlights these desalination plants’ efficiency, sustainability, and economic viability in addressing freshwater demands in their respective regions. Insights from this comparative study contribute to optimising seawater desalination processes, enhancing water resource management, and guiding future infrastructure development efforts in coastal areas.

Increasing the efficiency of bioreactor operation for cultivation of methane-oxidizing bacteria under conditions of decreasing carbon dioxide concentration in the cultural liquid

Objectives. The work set out to develop a bioreactor that incorporates a carbon dioxide removal unit within the apparatus gas phase, which is capable of operating without the need for supplementary compression apparatus. As part of testing the developed equipment in order to ascertain its capacity for enhanced biomass production, the principal fermentation system parameters that facilitate the optimal bioreactor productivity in conditions of carbon dioxide removal from the apparatus gas phase were identified.Methods. A series of tests were conducted on the fermentation unit with the objective of controlling the oxygen and carbon dioxide content in the gas phase of the bioreactor. This was achieved using an in-line gas analyzer fitted with electrochemical sensors. The oxygen and carbon dioxide content in the gas phase was determined by means of gas chromatography. The oxygen and natural gas flow rates were determined using a thermal electronic flow controller equipped with thermoresistive elements. The oxygen content of the cultural liquid was determined by means of an optical oxygen sensor with integrated transducer. The pH level in the bioreactor was monitored and maintained using an electrochemical pH sensor.Results. The efficacy of the newly devised jet-type bioreactor design, which permits the incorporation of a carbon dioxide removal unit into the fermentation system without requiring supplementary compression apparatus, was evaluated through experimentation. The system was tested with the carbon dioxide removal unit included in the design, resulting in a 64% increase in bioreactor productivity and a 18% reduction in oxygen consumption as a component of the gas supply.Conclusions. The operational parameters of a technological bioreactor that facilitate a stable continuous process of bacterial cultivation were identified.

Modeling and Analysis of Actuators in Multi-Pump Waterjet Propulsion Systems

Waterjet propulsion, which generates thrust by ejecting water jets, has attracted significant attention in modern high-performance vessels due to its efficiency, superior cavitation resistance, and excellent maneuverability. While previous research has primarily concentrated on optimizing the overall performance of waterjet propulsion systems, insufficient attention has been paid to the detailed dynamic modeling of actuators in multi-pump systems, a critical component for improving system control precision. This paper addresses this gap by developing dynamic models for the reversing bucket and rudder angle actuators in marine waterjet propulsion systems. Based on an in-depth analysis of their working principles and operational parameters, transfer function models are established to simulate actuator performance under various conditions, including wear, hydraulic oil leakage, and external disturbances. Key influencing factors for each condition are identified, and corresponding parameter-setting models are constructed. The models’ response speed and steady-state accuracy are validated through step and ramp tests, confirming their effectiveness and reliability. The proposed model is verified with real measurement experiments and comparisons. The findings of this study contribute new insights into the dynamic behavior of multi-pump waterjet propulsion systems and provide a solid theoretical foundation for the future development of optimized control strategies in complex marine propulsion environments.

Influence of Initial Gap, Voltage, and Additives on Zinc Microcolumn Morphology by Local Electrochemical Deposition

Local electrochemical deposition (LECD) is an innovative additive manufacturing technology capable of achieving precise deposition of metallic microstructures. This study delves into the ramifications of pivotal operational parameters—namely, the initial electrode gap, deposition voltage, and additive concentration—on the morphology of zinc microcolumns fabricated through LECD. A holistic approach integrating experimental methodologies with finite element simulations was adopted to scrutinize the influence of these variables on the microcolumns’ dimensions, surface morphology, and structural integrity. The findings reveal that augmenting the initial electrode gap results in microcolumns with larger diameters. Conversely, the deposition voltage primarily modulates the formation rate without exerting a notable impact on the columns’ dimensional attributes. The incorporation of additives enhances surface smoothness and diminishes column diameters; however, an overabundance of additives adversely affects the overall microstructure. Optimal parameters for the production of high-quality zinc microcolumns were determined to be a deposition voltage of 3.4 V and an electrode gap of 10 μm. These discoveries contribute pivotal insights for the refinement of LECD processes, with particular relevance to biomedical applications, such as the development of zinc-based bioabsorbable materials for orthopedic implants and cardiovascular devices.

Co-Optimization of Operational and Intelligent Completion Parameters of CO2 Water-Alternating-Gas Injection Processes in Carbonate Reservoirs

Recently, maximum reservoir contacting (MRC) wells have attracted more and more attention and have been gradually applied to CO2 WAG injections. During the use of MRC wells for CO2 WAG injections, intelligent completions are commonly considered to control CO2 breakthroughs. However, the design of the operational and intelligent completion parameters is a complicated process and there are no studies on the co-optimization of the operational and intelligent completion parameters for CO2 WAG processes. This study outlines an approach to enhance the oil recovery from CO2 WAG injection processes through the co-optimization of the operational and intelligent completion parameters of MRC wells in a carbonate reservoir. First, a simulation method is developed by using Petrel and Intersect. Then, a series of simulations are performed to prove the viability of intelligent completions and to investigate the effects of the timing and duration of the CO2 WAG injection, as well as the type, number, and placement of intelligent completion devices on the performance of a CO2 WAG injection by MRC wells. Finally, the imperialist competitive algorithm is used to co-optimize the operational and intelligent completion parameters for MRC wells. The results show that compared with the spiral inflow control device (SICD), autonomous inflow control device (AICD), labyrinth inflow control device (LICD), and annular interval control valve (AICV), the nozzle inflow control device (NICD) is the best type of intelligent completion device for MRC wells. There is an optimal installation timing, inflow area, and number of NICDs for a CO2 WAG injection by MRC wells. The NICDs need to be placed based on the permeability distribution. The oil recovery for the optimal case with the NICDs reached 46.43%, which is an increase of 3.8% over that of the base case with a conventional completion. In addition, compared with the non-uniformity coefficient of the base case (11.7), the non-uniformity coefficient of the optimal case with the NICDs decreased to 4.21. This is the first time that the co-optimization of the operational and intelligent completion parameters of a CO2 WAG injection has been reported, which adds more information about the practical applications of MRC wells in CO2 WAG injections for enhancing oil recovery in carbonate reservoirs.

Laparoscopic Nissen fundoplication is more cost-effective than open Nissen fundoplication in children

BackgroundNissen fundoplication is one of the most common surgical procedures for gastroesophageal reflux. Current and previous research comparing laparoscopic Nissen fundoplication (LNF) versus open Nissen fundoplication (ONF) in children suggest ambiguous conclusions. The purpose of this retrospective study was to compare the outcome for children operated with LNF or ONF at our institution and to evaluate the economic aspects.Methods32 consecutive patients (LNF: n = 18, ONF: n = 14) operated with Nissen fundoplication between the years 2011–2017 were included in the study. Data was collected by examination of the patient journals and preoperative, operative, postoperative, and post-discharge parameters were analyzed.ResultsCompared to ONF, the LNF group had shorter operating time (165.2 vs 216.6 min, p < 0.05), shorter overall operating room duration (315.0 vs 334.9 min, p < 0.05) and shorter postoperative hospital stay (3.8 vs 8.1 days, p < 0.05). The LNF group also required less morphine (1.2 vs 1.7 mg/kg, p < 0.05) and the total cost per case was 39% lower (261.1 vs 427.4 kSEK, p < 0.05). No difference was seen in postoperative complications and results.ConclusionLaparoscopic Nissen fundoplication is more cost-effective compared to open surgery and reduces postoperative hospital stay and morphine requirements.

Studies on Thermal Separation and the Effects of Geometrical and Operating Parameters on the Performance of Pressure Wave Refrigerators

Abstract Thermal separation in a pressure wave refrigerator (PWR) occurs primarily through the propagation of shock waves and reverse-moving rarefied waves produced by injecting a high-pressure gas into a low-pressure residual gas in a receiving tube or channel. The major advantages of PWRs are simple design, low cost, high reliability, low rotational speed, and efficiency comparable to the conventional turbo-expanders. The objectives of this work are to understand the thermal separation in PWRs and to study the effects of various geometrical and operating parameters on the performance of PWRs. Two-dimensional computational fluid dynamics (CFD) simulation using a finite volume method is adopted for this study. The results indicate that the temperature and pressure profiles of the fluid inside the receiving tube just before the discharge, in the region about half the tube length from the inlet nozzle, strongly govern the performance of a PWR. The operating frequency at which the isentropic efficiency attains the first peak value is determined in a generalized way. Within the chosen geometrical and operating parameters, the optimized tube length, operating frequency, and pressure ratio are 2 m, 50 Hz, and 2.5, respectively. The findings in this article will be useful in designing and operating PWRs optimally.

Implementation of Quality of Design for the Development of Bilayer Tablet

Different drug release properties for different drugs contained in each layer of a bilayer tablet are rarely achievable with regular tablets. Additionally, these tablets help avoid physicochemical incompatibilities between medications and excipients. The successful production of such more complicated dosage forms depends on screening the material qualities of APIs and excipients and optimizing the processing parameters of each unit operations of the manufacturing process. In order to meet safety and efficacy regulations, these operations need to be properly monitored and managed to produce a drug product with acceptable quality and performance. Blending, granulation, pre-compression, and main compression are critical stages when formulation qualities and production processes should be tuned to avoid problems like weight variation, segregation, and delamination of particular components. Bilayer tablets, as opposed to ordinary tablets, offer distinct drug release properties for certain medications that are housed in each layer. These tablets also help to avoid physicochemical incompatibilities between drugs and excipients. The successful manufacturing of such more complex dosage forms depends on screening the material attributes of API and excipients and optimizing the processing parameters of individual unit operations of the manufacturing process in order to achieve safon of layers, which is frequently encountered during the production of bilayer tablets. For the quality and performance of the medication product to be acceptable, these processes need to be properly watched over and managed. The main objective of this review is to establish the foundation for implementing the Quality by Design (QbD).

Investigating the Effect of Incident Intensity on Single-junction GaAs PV Cells Conversion Efficiency at Different Temperatures

Abstract Laser Power Transmission (LPT) is emerging as a highly promising method for wireless energy transfer, particularly for extending the operational endurance of small unmanned aerial vehicles (UAVs) and supporting the construction of space-based solar power stations. This study investigated the optimal operational parameters of single-junction gallium arsenide&amp;#xD;(GaAs) photovoltaic (PV) cells under laser diode (LD) irradiation to enhance the efficiency of&amp;#xD;LPT systems. A detailed theoretical analysis was conducted to examine the effects of incident light intensity and spot size on the photoelectric conversion efficiency of GaAs PV cells across different temperature ranges. Experimental results demonstrated that the optimal efficiency of the photovoltaic cell is associated with a rise in incident intensity from 0.35&amp;#xD;W/cm² to 0.65 W/cm² as the temperature decreases from 55°C to 5°C, that higher incident intensities are required for optimal efficiency when PV cells operate at lower temperatures, and the 2cm photovoltaic cell can attain a conversion efficiency exceeding 50% only when exposed to a 2cm incident light spot, that high efficiency in photovoltaic cells is attainable solely when the size of the incident light spot is as closely matched to the cell's size as possible. Additionally, this study provides an in-depth discussion of factors limiting photoelectric conversion efficiency and the underlying mechanisms at various temperature conditions.&amp;#xD;

ОБЕСПЕЧЕНИЕ ЭКСПЛУАТАЦИОННЫХ ПАРАМЕТРОВ ШПИНДЕЛЕЙ МЕТАЛЛОРЕЖУЩИХ СТАНКОВ НА ЭТАПАХ РЕМОНТА И ВОССТАНОВЛЕНИЯ

The study objective is to develop a model for determining the parameters of the spindle bearing assembly of metal-cutting machines, taking into account the minimum runout of the functional surface. The task to which the paper is devoted is to develop a technique for evaluating deviations from the alignment of the functional surface of a part (spindle) relative to the axis of the base necks. Research methods: modeling the influence of shape accuracy parameters and the relative position of the spindle support necks on the radial runout of the base cone using the theory of dimensional relationships. The novelty of the work: for the first time the effect of the accuracy parameters of the mating parts on the performance of the spindle assembly is analyzed and recommendations are given to reduce the radial runout of the functional surface. Research results: a model is developed to determine the parameters of the shape error and the error of the relative position of the surfaces and their effect on the radial runout of the spindle functional surface at the stage of the bearing assembly. Conclusions: in order to achieve the specified operational parameters of the spindle assembly at the stages of restoration and repair, it is necessary to develop a technique for performing control and assembly operations, taking into account the influence of shape accuracy parameters and the accuracy of the mutual positioning of the mating surfaces of all parts of the assembly unit.

Continuous Flow Electrocoagulation System for Enhanced Phosphorous Removal in Decentralized Wastewater Treatment Systems

Decentralized wastewater treatment systems (DWTS) are significant contributors to the eutrophication of surface water bodies due to a lack of treatment mechanisms that target dissolved phosphorus removal. Existing advanced treatment systems are expensive to operate, large in nature, and require frequent maintenance, making them unattractive to DWTS owners. This study aims to investigate the development of a continuous flow treatment system that uses electrocoagulation (EC) to remove dissolved phosphorus from small wastewater streams such as septic tank effluent (STE). Operational parameters, including system hydraulic retention time (HRT), applied current density, and wastewater composition, were optimized to maximize total phosphorus (TP) removal most cost-effectively. Using an HRT of 10 min, an applied current density of 2.0 mA/cm2, and an influent concentration of 20 mg/L, the orthophosphate (OP) and TP removal percentages achieved were 99.9 and 88.1%, respectively. Under these conditions, the average effluent Al3+ concentration in the treated effluent was measured to be 1.0 mg/L while the total suspended solids concentration was measured to be 51 mg/L. The operation cost was estimated to be 0.056 CAD/m3. The results demonstrate that the EC reactor is effective in removing dissolved phosphorus from wastewater and is therefore a viable option in mitigating the risk of downstream eutrophication caused by inadequately treated STE.

Identification of operational modal parameters for a large floodgate under hydraulic excitation using the blind source separation improved by Hankel matrix singular value and adaptive variational mode decomposition

Identification of operational modal parameters for a large floodgate under hydraulic excitation using the blind source separation improved by Hankel matrix singular value and adaptive variational mode decomposition

Simulation of an allyl chloride production process via the propylene chlorination route in ChemCAD simulator

Allyl chloride is typically used to make intermediates for downstream derivatives such as resins and polymers, and in the production of epichlorohydrin. The present work describes the simulation and conceptual design of an allyl chloride production process via the propylene chlorination route in ChemCADÒ simulator, to know the mass and energy balances of the intermediate and final streams, the operating and design parameters of some equipment, and other results of interest. The production process consists of a fired heater, a fluidized bed reactor, a waste heat boiler, six shell and tube heat exchangers, two compressors, a gas-liquid absorber and four distillation columns. About 1.336,307 kg/h of allyl chloride are produced at the distillate of the last distillation column with a purity of 99,92%, while pure propylene, 2-chloropropene and an aqueous solution of HCl 32,4 wt. % are also obtained as byproducts. A first-of-its-kind simulation model was obtained in ChemCADÒ, which could be employed for further optimization studies and productivity increment analysis.

Design and Implementation of a Virtual Hoisting System: A Digital Twin Approach for Early Warning and Fault Detection

Mine hoists are vital for efficiently transporting materials and personnel between surface and underground mining operations, making their safety and reliability paramount. However, conventional monitoring approaches, which rely on distributed sensors or video surveillance, are limited in their ability to capture the global dynamics of the system, leading to suboptimal decision-making and potential safety risks. This research introduces the integration of digital twin technology into the monitoring and management of mine hoists to address these challenges. This study uses Unity-based modeling to create a virtual system capable of real-time synchronization with its physical counterpart. The digital twin simulates dynamic load changes, predicts potential faults, and optimizes operational parameters through intelligent algorithms. A robust monitoring framework was developed, consisting of a multi-layered architecture that integrates physical systems, real-time data collection, and virtual simulations. Field tests on a multi-rope friction hoist verified the system’s performance, with results demonstrating improved stability, accuracy, and predictive capabilities. A health evaluation model further enhances safety by categorizing the hoist’s operational state into health levels such as ‘healthy,’ ‘sub-healthy,’ ‘warning,’ and ‘fault.’ This model identifies critical risks, such as wire rope tension anomalies, and provides early warnings, ensuring timely interventions.

Fast electrons produced by lower hybrid wave and effects on plasma–wall interactions

Abstract Lower hybrid wave (LHW) current drive plays a crucial role in sustaining steady-state (SS) discharges on the Experimental Advanced Superconducting Tokamak (EAST). Hotspots frequently form on the wave antenna and guard limiters during SS operations. Although both experimental and theoretical studies suggest that fast electrons could be responsible for these hotspots, the underlying mechanisms of fast electron generation under typical EAST operational parameters and their impact on the hotspots remain unresolved. In this work, particle-in-cell simulations are used to investigate the interactions between LHWs and electrons in front of the antenna, taking into account the realistic incident power spectra and localized field effects. The results show that, due to resonance overlap, fast electrons are produced through resonant interactions between electrons and LHW components with a high parallel refractive index (N ∥). The velocity distribution function in velocity space is found to significantly depend on plasma parameters near the antenna, such as q 95, electron temperature, and input power. These fast electrons notably enhance the sheath potential on the guard limiters and increase the heat flux to the wall.

Feasibility of electron cyclotron resonance heating for high-field and high-density tokamak COMPASS Upgrade

Abstract Electron cyclotron resonance heating is one of the additional heating systems that is going to be installed at the future high-field tokamak COMPASS Upgrade in Prague. Experimental scenarios cover a wide range of operational parameters, thus the designed heating system has to be exceptionally versatile. The simulations of wave propagation in plasma have been performed using the TORBEAM code. The obtained results yield important information about density limitations and other constraints of ECRH at COMPASS Upgrade, which are necessary for the subsequent design phase. A brief description of intended experimental scenarios is provided together with simulations of the influence of ECRH on COMPASS Upgrade plasma. Efforts should be made to prevent high-density discharges in H-mode plasma. If the high densities can be prevented, the 105/140~GHz frequency heating system provides sufficient heating in most experimental scenarios. The utilization of 170 GHz would be beneficial for intermediate magnetic field scenarios as well. In the future, the potential upgrade towards the 200+ GHz systems would help to tackle the problems with natural H-mode density.

Starch-ZnCr/LDH Composite and ZnCr-LDH: Synthesis, Characterization, and Adsorption Efficiency to Remove Congo Red from Aqueous Solution

Background: To bring new materials with high performance, a large number of composites, among others, such as starch-laminated double hydroxides (starch/ZnCr-LDH), have been produced, which have shown significant adsorption predisposition to remove heavy metals and dyes. These LDHs display great adsorption potential due to their high anion exchange capacity, large surface area, and good thermal stability. Objective: This study aimed to develop starch-ZnCr-hydroxide composite (S/ZnCr-LDH) as a new material and investigate its performance in removing various anionic dyes compared to ZnCr- LDH. Methods: The starch-ZnCr-laminated double hydroxides (S/ZnCr-LDH) and ZnCr-LDH composites were prepared by the co-precipitation method and their structures were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential thermogravimetric/ thermal analysis (TG/DTA) Scanning electron microscopy (SEM), and Energy Dispersive Xrays Spectroscopy (EDX). Results: The effects of different operating parameters, such as pH, initial CR concentration, contact time, and adsorbent dose, on CR removal were studied. The results showed that the S/ZnCr- LDH composite is more efficient for CR removal, reaching 99% at pH 3, while ZnCr-LDH presented a removal efficiency of 90%. Isothermal data were processed according to the Langmuir, Freundlich, and Temkin models. According to the results, Langmuir's isothermal model best matched the experimental data, with a maximum adsorption capacity of 252. 92 and 236. 98 mg/g for S/ZnCr-LDH and ZnCr-LDH, respectively. The adsorption kinetics corresponded to the PSO model. CR dye molecules were adsorbed to different sites on the S/ZnCr-LDH composite based on various interactions, such as electrostatic interactions, hydrogen bonds, and Van der Waals forces. Conclusions: S/ZnCr-LDH composite displays the highest capacity to remove CR dye molecules compared to ZnCr-LDH.

Sol-Gel Synthesis of TiO2 from TiOSO4 (Part 2): Kinetics and Photocatalytic Efficiency of Methylene Blue Degradation Under UV Irradiation

The sol-gel process was used to create titanium dioxide (TiO2) nanoparticles, a nanocrystalline semiconductor. How several synthesis factors, such as titanium precursor concentration, annealing temperature, and peptization temperature, affected the structural and morphological properties of TiO2 nanoparticles were thoroughly explored. X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), measurements of the specific surface area and pore size using the BET method, and UV-visible diffuse reflectance spectroscopy were all used in this investigation. The specific surface area determined by BET analysis decreased with increasing calcination temperature. The XRD analysis showed that a composite sample consisting mainly of anatase with minor brookite phases was obtained when the titanium precursor concentration ranged between 0.2 and 0.4 M, whereas a concentration of 0.5 M resulted in the formation of pure anatase. The photocatalytic activity of the synthesized TiO2 powders under different operational parameters was evaluated for the common commercial textile dye, i.e., methylene blue (MB). It was experimented that the model pollutant decoloration follows the Langmuir–Hinshelwood (L-H) model. In view of this detailed research work, it was observed that the TiO2 produced with a titanium precursor concentration of 0.3 M, a pH value of 5 during the peptization step, and an annealing temperature of 600 °C were found to be the best conditions for this catalytic degradation process. When used in conjunction with a TiO2 concentration of 0.04 g/L and a reactor suspension pH value of 6.0, the TiO2 catalyst produced a stunning 98% degradation of methylene blue under these circumstances.

Adsorption Performance and Mechanistic Pathways of Raw Powdered Pine Cone Toward the Removal of Dye and Cr(VI)

ABSTRACTThis work aims to valorize pine cones powder (PCP), an agricultural waste, as a bioadsorbent for the removal of a cationic dye, Rhodamine B (RhB), and hexavalent chromium Cr(VI) from an aqueous solution. The adsorbent was characterized by scanning electron microscopy (SEM), Fourier‐transformed infrared (FTIR), and X‐ray diffractometer (XRD) spectroscopy. Adsorption studies were carried out in a batch mode under different operating parameters like initial solution pH (2–11), adsorbent dosage (0.025–0.6 g), initial contaminant concentration (20–100 mg/L), temperature (283–328K), contact time (0–120 min), and ionic strength (NaCl, MgCl2, CuSO4, Na2SO4, and FeCl3). The optimum conditions for adsorption for Cr(VI) were; ([Cr(VI)] = 30 mg/L, pH = 2, adsorbent dose = 1.5 g/L, T = 25°C), and for RhB: ([RhB] = 30 mg/L, pH = 4.6, adsorbent dose = 4 g/L, T = 25°C). Under these conditions, the maximum adsorption capacities reached were 19.861 and 6.565 mg/g, for Cr(VI) and RhB, respectively. The inhibiting effect of the studied salts on RhB dye and metal ion removal is as follows: FeCl3 &gt; CuSO4&gt; MgCl2&gt; Na2SO4&gt; NaCl. The Freundlich isotherm described the best the adsorption of Cr (VI) and RhB onto PCP, since it gave the highest R2 values (R2 ≥ 0.983) associated with the lowest error values (χ2, RMSE, and Δq). The calculated Dubinin–Radushkevich mean energy (E) is less than 8 kJ/mol. It is 3.391 kJ/mol for Cr(VI) and 2.310 kJ/mol for RhB sorption, respectively, confirming the physical character of adsorption onto PCP sorbent. Experimental data for Cr(VI) and RhB ion adsorption onto PCP, fitted well the pseudo‐second‐order kinetic model (R2 ≥ 0.997). According to the thermodynamic analysis, the retention of Cr(VI) and RhB followed a physisorption, endothermic, and spontaneous process at all temperatures for Cr(VI), and at higher temperatures for RhB dye. These results suggest that raw PCP may be envisaged as a promising biosorbent for water remediation without the need of costly heat and activation processes as a cheap and sustainable adsorption process.

Design and Optimization for Straw Treatment Device Using Discrete Element Method (DEM)

Due to the dense crop residue in the Huang-Huai-Hai region, challenges such as large resistance, increased power consumption, and straw backfilling arise in the process of no-till seeding under the high-speed operations. This paper presents the design of a straw treatment device to address these issues. The cutting edge of a straw-cutting disc is optimized using an involute curve, and the key structural parameters of the device are designed by analyzing the process of stubble cutting and clearing. In this study, the Discrete Element Method (DEM) was employed to construct models of compacted soil and hollow, flexible wheat straw, forming the foundation for a comprehensive interaction model between the tool, soil, and straw. Key experimental variables, including working speed, rotation speed, and installation centre distance, were selected. The power consumption of the straw-cutting disc (PCD) and the straw-clearing rate (SCR) were used as evaluation metrics. Response surface methodology was applied to develop regression models linking the experimental factors with the evaluation indexes using Design-Expert 12 software. Statistical significance was assessed through ANOVA (p &lt; 0.05), and factor interactions were analyzed via response surface analysis. The optimal operational parameters were found to be a working speed of 14 km/h, a rotation speed of 339.2 rpm, and an installation centre distance of 100 cm. Simulation results closely matched the predicted values, with errors of 1.59% for SCR and 9.68% for PCD. Field validation showed an SCR of 86.12%, improved machine passability, and favourable seedling emergence. This research provides valuable insights for further parameter optimization and component development.