Overview of Factors Affecting Dust Deposition on Photovoltaic Cells and Cleaning Methods

Dust deposition on the surface of photovoltaic (PV) cells poses a significant challenge to their efficiency, especially in arid regions characterized by desert and semi-desert conditions. Despite the pronounced impact of dust accumulation, these regions offer optimal solar radiation and minimal cloud cover, making them ideal candidates for widespread PV cell deployment. Various surface cleaning methods exist, each employing distinct approaches. Choosing an appropriate cleaning method requires a comprehensive understanding of the mechanisms involved in both dust deposition on module surfaces and dust adhesion to PV cell surfaces. The mechanisms governing dust deposition and adhesion are complex and multifaceted, influenced by factors such as the nature and properties of the dust particles, environmental climatic conditions, characteristics of protective coatings, and the specific location of the PV installation. These factors exhibit regional variations, necessitating the implementation of diverse cleaning approaches tailored to the unique conditions of each location. The first part of this article explores the factors influencing dust deposition on PV cell surfaces, delving into the intricate interplay of environmental variables and particle characteristics. Subsequently, the second part addresses various cleaning methods, offering an analysis of their respective advantages and disadvantages. By comprehensively examining the factors influencing dust accumulation and evaluating the effectiveness of different cleaning strategies, this article aims to contribute valuable insights to the ongoing efforts to optimize the performance and longevity of photovoltaic systems in diverse geographical contexts.

Combined Removal of Surface Moisture and Dust from Feed Coal for Coal Dry Cleaning with an Air-solid Fluidized Bed

A demonstration plant and a commercial plant employing coal dry cleaning technology with an air-solid fluidized bed were built in China. The operation practice of these two plants shows that the surface moisture and the fines or dust of feed coal must be well controlled as low as possible. For this purpose, a new process of combined removal of surface moisture and dust from feed coal using a vibrated fluidized bed dryer was investigated in a batch test apparatus and a pilot test system. A mathematical model on drying kinetics of coal surface moisture was developed and three empirical formulas of the model coefficient involving the main operating variables were determined based on the test results from the batch test apparatus. The mathematical model shows that the surface moisture retained in coal during drying decreases exponentially with drying time. According to this model, a new divisional heat supply mode, in which the inlet gas of higher temperature was introduced into the fore part of the dryer and the inlet gas of lower temperature into the rear part of the dryer, was employed in the pilot test system. The pilot tests show that 1） the new divisional heat supply mode is effective for lowering down the average temperature and reducing the total heat loss of the outlet gas off the dryer, 2） the moist coal of about 60 g/kg surface moisture contentcan be dried to about 10 g/kg, and simultaneously the fines （〈1mm in diameter） adhering to the surface of coarse coal particles are completely washed off by the gas flow.

Low-Cost Automated PV Panel Dust Cleaning System for Rural Communities

Dust accumulation on photovoltaic (PV) panels degrades PV panels’ performance;leading to decreased power output and consequently high cost per generated kilowatt. Research addressing the severity of dust accumulation on PV panels has been ongoing since the 1940s, but proposed solutions have tended to increase the cost of PV systems either from oversizing or from cleaning the system. The objective of this work, therefore, is to design and implement a low-cost affordable automated PV panel dust cleaning system for use in rural communities of Sub-Saharan Africa (SSA);where financial resources are limited and significantly strained in meeting livelihood activities. Complete design and implementation details of a prototype system are provided for easy replication and capitalization on PV systems for sustainable energy needs. The system detects dust based on the innovative use of light-dependent resistors. Testing and observation of the system in operational mode reveal satisfactory performance;measured parameters quantify a power output increase of 33.76% as a result of cleaning dust off the PV panel used in the study.

Solar Panels Cleaning Frequency for Maximum Financial Profit

Allowing the dust to accumulate on solar panels without adequate cleaning leads to huge monetary losses. Proper judgment of when to call for washing of solar panels is a compromise between gross costs of cleaning the panels and how much reduction in efficiency of solar panels can be tolerated. In this paper, we derive a formula for the optimal number of days between cleaning cycles of a solar array by minimizing the cost of cleaning the array and the lost revenue from the unclean panels. The formula will aid in deciding cleaning periods based on the environment in which the solar panels are installed and cost incurred from undertaking the washing process.

Closer Approximation to Optimize Solar Panels Performance with Cleaning Cycle: A Follow-Up

The performance of solar panels significantly degrades due to dust accumulation but cleaning too frequently will severely impact the financial benefits of the installation of solar panels. This paper assumes a realistic linear model for accumulation of dust on the solar panels and the resulting hourly average of absolute loss of efficiency in solar panels. This model accurately depicts the fact that energy production by solar panels occurs during sunshine hours only and also accounts for the degradation in the efficiency of solar panels due to dust accumulation throughout the entire day. Based on this, the optimal number of days for maximum financial profit and the critical number of days (above which there is no profit in installing solar panels) have been estimated. Furthermore, we have suggested a formalism to help estimate the finances for self-cleaning technology for PV system and also for calculating the minimum payback period for installing solar panels with the financial cost of the cleaning cycles properly considered. This research could be motivation for companies in developing self-cleaning mechanism for PV system.

An Experimental and Numerical Study on the Cleaning of Pleated Bag Filters Using Low-Pressure Pulsed-Jets

Pulsed-jet cleaning is recognized as the most efficient method to regenerate bag dust collectors traditionally used in industrial processes to control the emission of particulates.In this study,non-woven needle felt filter bags with and without a film coating material have been analyzed considering different geometries(different number N of pairs of pleated filter bag sides)in the frame of dedicated low-pressure pulsed-jet cleaning experiments.The flow structure inside the bag and the response characteristics of its wall have also been analyzed numerically through a computational fluid-dynamics/structural-dynamics(CFD-CSD)unidirectional fluid-solid coupling method.As shown by the experiments,the peak pressure(P_(0))on the wall of the filter bag with N=8 and 12 is higher,which indicates dust can be removed more effectively in these cases.The peak pressure on the wall increases first and then decreases along the direction of the bag length,while the peak pressure of the pleated filter bag with nonwoven needled felt film coating is greater than that without film coating.A comprehensive analysis of the time variation of acceleration,deformation,strain,stress and other factors,has led to the conclusion that the pleated filter bag with N=12 would be the optimal choice.

Image Analysis on Detachment Process of Dust Cake on Ceramic Candle Filter

Based on the analysis of high-speed video images, the detachment behavior of dust cake from the ceramic candle filter surface during pulse cleaning process is investigated. The influences of the dust cake loading,the reservoir pressure, and the filtration velocity on the cleaning effectiveness are analyzed. Experimental results show that there exists an optimum dust cake thickness for pulse-cleaning process. For thin dust cake, the patchy cleaning exists and the cleaning efficiency is low; if the dust cake is too thick, the pressure drop across the dust cake becomes higher and a higher reservoir pressure may be needed. At the same time there also exists an optimum reservoir pressure for a given filtration condition.

Aerosol Filtration Application Using Fibrous Media—An Industrial Perspective

Filtration of aerosol particles using non-woven fibrous media is a common practice for air cleaning. It has found wide applications in industries and our daily lives. This paper overviews some of these applications and provides an industrial perspective. It starts from discussing aerosol filtration theory, followed by a brief review on the advancement of filtration media. After that, filtration applications in respiratory protection, dust collection, and engine in-take air cleaning are elaborated. These are the areas that the author sees as the typical needed ones in China's fast pace economical development endeavor, where air filtration enables the protection of human health, environment and equipment for sustainability.

特大型硫磺储运系统粉尘防控技术应用总结

普光天然气净化厂设计硫磺产能2.4 Mt/a,是亚洲最大的硫磺生产基地。针对该厂特大型硫磺储运系统存在的皮带输送单元落地硫磺粉尘扩散、地下廊道硫磺粉尘超标、装车单元粉尘闪爆等安全隐患,围绕固体硫磺仓储、输送、装车环节开展粉尘风险防控难题攻关,研究皮带机集成清扫、地下廊道粉尘消减及粉尘闪爆综合治理技术,形成了特大型固体硫磺储运系统全流程粉尘防控关键技术,实现了安全清洁生产,提高了装置本质安全水平。

卧式三角型滤筒的脉冲喷吹清灰性能

【目的】为优化卧式三角型滤筒除尘器的清灰性能,探究不同喷吹气流对滤筒内部压力分布的影响,获得不同喷吹孔型式对三角型滤筒的清灰性能的影响规律。【方法】分别采用直管喷吹孔、文氏里管、散射喷嘴、新型曲面诱导引射器共4种喷吹孔型式的诱导引流装置对卧式三角型滤筒开展冷态脉冲实验,以侧壁压强峰值和相对标准偏差作为评价清灰性能的技术指标,分别探讨不同条件下的喷吹射流对滤筒内壁压力分布的影响。【结果】在喷吹压强分别设为0.3、0.4、0.5 MPa的条件下,采用直管、文丘里管、新型曲面诱导引射器时喷吹距离分别设为150、200、250、300、350、400 mm,采用散射喷嘴时喷吹距离分别设为25、50、75、100、125、150、175 mm,则采用直管、文丘里管、散射喷嘴、新型曲面诱导引射器时的平均侧壁压强峰值分别为1037、1758、952、1533 Pa,相对标准偏差分别为0.76、0.58、0.09、0.16;采用新型曲面诱导引射器喷吹孔时,比采用散射喷嘴时的清灰强度高61%,比采用文丘里管时的相对标准偏差小0.47。【结论】新型曲面诱导引射器同时兼顾对侧壁压强峰值和相对标准偏差的要求,在4种喷吹孔型式中清灰性能最佳。

洗煤厂破碎筛分除尘系统升级改造可行性研究

为了优化厂区工作环境,实现全面清洁生产的目标,针对山西某洗煤厂破碎筛分工序的扬尘问题,通过分析现有设备运行现状,结合行业标准及设计规范要求,得到了符合现场实际生产情况的除尘系统升级改造方案,并对方案进行系统性验算,以确保方案的合理性,既提高了工人工作环境质量,又降低了矿粉以扬尘的形式流失,实现厂区的达标排放要求,具有良好的社会效益。

光伏组件表面积灰监控系统设计与实现

光伏组件表面积灰会影响组件的发电效率,降低光伏电站运行的经济性。为了能够监测光伏电站中组件表面的积灰状态,进而基于监测数据进行光伏电站清洗运维优化方法的研究,提出一种光伏电站组件表面积灰监控系统。该系统中,下位机采用STM32F407微处理器扩展ADS1256模数转换器采集与积灰相关的多种传感器信号,并通过无线传输模块将数据传给上位机监控软件。基于LabVIEW开发的上位机监控软件通过串口接收数据,处理并存储数据后,根据相应数据对光伏电站的清洗时间进行优化。经过实验测试,本系统能够准确地采集、传输、处理和储存数据,监测光伏电站组件表面的积灰状态并实现电站清洗时间的规划,对光伏电站清洗运维优化有重要意义。

低硫精矿焙烧系统清洁生产实践

分析了铜陵有色金属集团股份有限公司铜冠冶化分公司的低品位硫精矿焙烧系统存在的问题,针对现场跑冒滴漏等现象,采用有效的技术和设备确保了焙烧系统的稳定运行和清洁生产,减少了生产现场扬尘污染,实现了污水梯级利用和固体废渣的回收利用。

多晶硅硬密封球阀的最新设计特点

随着多晶硅生产工艺改进实现提纯度高的分析与管线使用验证,总结多晶硅硬密封球阀的性能特点。与常规硬密封球阀相比,多晶硅硬密封球阀应具有防尘、高硬度、防腐的特点。密封面应采用结合强度高、敷熔后密封层硬度高且耐磨的材料。密封面应具有自清洁与自研磨性能,球体需有引流性能,可减轻阀门启闭力扭矩,并且可以预防阀腔硅粉堆积导致阀门卡死,阀体与阀座都需要设计有效的防尘功能来确保阀座运动有效性等。

输煤系统粉尘治理策略研究

针对输煤系统转载环节粉尘治理难度大的问题,根据输煤系统输送物料的特性,通过分析输煤系统转载环节粉尘产生的机理,结合粉尘治理技术现状,多维度针对各环节粉尘治理采取措施,提出了可用于输煤系统转载环节的多方案组合式粉尘治理策略。结合输煤系统现场水源条件,分别建立有水及无水条件下的粉尘综合治理方案,在实际工程案例中加以应用,检测应用前后转载环节粉尘浓度,验证了所述综合治理方案的可行性,为今后输煤系统粉尘治理方案的选择提供了参考。

汉钢冶金粉尘在烧结工序综合回收利用的研究

汉钢烧结厂通过冶金粉尘清洁运输、分类堆储及消化,建立了冶金粉尘应对调整模型,实现了钢铁企业冶金粉尘在烧结工序的综合回收利用,这一创新举措不仅有效地降低了烧结工序生产成本,实现了冶金粉尘的清洁运输,还为冶金行业提供了可持续发展的解决方案。

吹灰上料拆包工艺自动化设备的设计与应用

在海洋石油勘探开发大宗料服务方面,吹灰上料拆包作业存在着人工劳动强度大、粉尘外溢严重、作业效率低、耗用机具人力多、职业健康安全隐患大等问题。为解决这些问题,文章设计了一款工艺自动化拆包设备,集成吨包输送、抓取、破包、粉料传输、废袋回收、密闭除尘等功能于一体,实现了吨包拆破自动化、密闭除尘和废袋自动收集的目标。这达到预期效果,消除破包环节人工操作模式,降低工人操作强度,减少机具人力占用消耗,消除粉尘外溢,改善提高工人作业环境。

鼠浪湖矿石码头皮带机系统环境治理的研究与应用

皮带机是一种常用的物料输送设备,广泛应用于矿石码头等场所,本文旨在探讨专业铁矿石码头皮带机系统扬尘治理的问题。首先对皮带机系统扬尘的特点进行分析,明确扬尘易发部位及其特点,其次指出传统除尘技术存在的问题,最后提出一套新的技术方案,并对其实施效果进行了阐述。

基于气象数据的光伏组件积灰损失评估方法研究

光伏组件表面的积灰对其发电性能会产生严重影响,进而影响整个光伏电站的发电效率和输出稳定性。因此,准确评估实际应用的光伏电站中光伏组件表面积灰造成的损失(下文简称为“积灰损失”),制定合理的清洗策略,将有助于提升光伏电站的发电量。提出了一种基于气象数据进行光伏组件积灰损失的评估方法,建立了积灰损失评估模型,并以光伏电站现场实际发电数据和气象数据为数据基础,通过实验对传统的基于光伏电站系统效率(PR)的积灰损失评估方法和基于气象数据的光伏组件积灰损失评估方法进行了对比验证。研究结果表明:与传统的基于光伏电站PR的积灰损失评估方法相比,基于气象数据的光伏组件积灰损失评估方法具有更好的预测性能,其模拟得到的发电量更接近实际发电量状态;可用于快速定量评估光伏电站的积灰程度,为光伏电站的发电性能模拟提供可靠的数据支持。

煤磨袋收尘器超洁净排放改造实践

石家庄某水泥厂煤磨袋除尘器由气箱脉冲式袋除尘器改造为行喷吹式袋除尘。改造要求袋除尘器出口颗粒物标况下排放≤5 mg/m^(3),设备阻力≤1 500 Pa。改造利用原气箱脉冲袋除尘器的壳体、灰斗及进出气管道等,新制作整体式净气室,袋室和烟道加高3 m,采用Φ130 mm×5 500 mm的拒水、防油、防静电涤纶覆膜滤袋,根据需要适当增加泄爆阀的面积,采用新的脉冲清灰系统。改造后顺利通过了业主和当地环保部门的检测,经过1年的运行,设备达到了低阻力、超洁净排放的改造目标。