|
所在平台: Coursera |
课程主页: https://www.coursera.org/learn/sustainability-fuels-ash-chemistry-deposits-corrosion-additives
课程评论：没有评论
课程名称：可持续燃料能量利用中的灰分相关操作挑战 课程概述：本MOOC的基本理念是展示燃料特性、灰分结垢、结焦、腐蚀及微量元素转化等方面的最新数据，为学生和行业人员提供一个易于掌握和讨论最新研究成果的课程。这不仅确保了研究的理解和应用，还为学生和行业提供了一个反馈平台，以便研究小组能够获得来自DTU的重要新研究主题建议。 课程的具体目标包括： - 解释固体燃料（如煤、生物质、废物等）之间的基本物理和化学差异，能够对固体燃料进行表征和解析。 - 理解和利用先进燃料及灰分析数据（如SEM、DTA/TGA、化学分级、灰熔点）。 - 详细说明灰分形成的关键元素如何释放至气相、气溶胶及飞灰颗粒的形成机制，以及灰分如何从气体团聚体运输到热交换表面。 - 量化沉积物的积累、熔融和脱落过程。 - 解释热能转换系统中高温腐蚀的基本原理。 - 计算温度和成分对粘度的影响、沉积物的温度分布、积累和熔融速率，以及随时间变化的孔隙率变化。 课程大纲包括： 1. 课程简介与学习动机：介绍课程的基本内容。 2. 燃料与灰分化学及特征：包括7节课，涵盖燃料与灰的表征，介绍多种特征分析技术。 3. 关键灰分形成元素的释放：介绍在热转换过程中一些关键元素如K、S、Cl的释放方式，包含4节课的量化方法。 4. 飞灰和气溶胶的形成：介绍灰分形成后的飞灰和气溶胶的基本道理及健康影响。 5. 灰分颗粒的运输与粘附：分析灰分成分的运输和粘附机制。 6. 沉积物的积累、固化和脱落：研究沉积物的形成过程及其复杂的物理和化学交互现象。 7. 高温Cl腐蚀：讨论沉积物与热交换管之间的化学交互，尤其是生物质和废物燃料的腐蚀问题。 8. 使用添加剂减少沉积物形成和高温腐蚀：探讨使用添加剂在锅炉的自由段条件下调控化学成分以减少腐蚀和环境影响。 9. 丹麦灰分与沉积物形成的案例研究：讨论在丹麦的几个经典燃料锅炉案例研究，展示灰分与沉积物的形成及其影响。 本课程适合有志于可持续能源研究与应用的学生和从业人员，旨在提高其在相关领域的专业知识和实用技能。
Name:Brief MOOC Introduction and Incitement for Following This
Description:This module will introduce the basic content of the course to the student.
Name:Fuel and Ash Chemistry and Characterization
Description:Module 2 (Fuel and Ash Chemistry and Characterization) is subdivided into 7 lessons, dealing with fuel and ash characterization, and is meant as an introduction to different techniques, applied to characterize fuels or ash samples. Both simple techniques like proximate and ultimate analyses, but also advanced techniques like Simultaneous Thermal Analysis (STA) analysis of ash fusion and Scanning Electron Microcospy (SEM), are introduced. There is also included an introduction to online fuel databases.
Name:Release of Critical Ash-Forming Elements
Description:This module gives an introduction to how critical ash-forming elements like K, S, and Cl, but also Na, Zn and Pb, are released from fuels, during thermal conversion.Module 3 (Release of Critical Ash-Forming Elements) deals with release of critical ash-forming elements, mainly K, S and Cl, but also Na, Zn, and Pb. The module has four lessons and deal with both fixed-bed and entrained flow release quantification. Further, there is a thorough introduction to K-release from K-Ca-P-rich ashes.
Name:Formation of Fly Ash and Aerosols
Description:As soon as the critical ash-forming elements have been released to the gas, formation of fly ash and aerosols begin, which is the subject of Module 4 (Formation of Fly Ash and Aerosols). This module is subdivided into 5 lessons, introducing both fundamental and detailed physical aspects of residual fly ash formation, as well as formation of and harmful health effects of combustion-derived aerosols. Finally, there is a thorough introduction to the pioneering Danish full.scale aerosol formation studies at Haslev respectively Slagelse CHP.
Name:Transport and Adhesion of Ash Particles
Description:Next natural step in the chain of events leading to troublesome deposit formation is the transport and adhesion of ash species (gases, aerosols and particles), which is the subject of Module 5 (Transport and Adhesion of Ash Particles), thoroughly addressing both important transport mechanisms like diffusion, thermophoresis and inertial impaction, as well as mechanisms of adhesion and different criteria for sticking of ash species.
Name:Deposit Build-Up, Consolidation and Shedding
Description:As soon as the ash species stick to the surface of the deposit, a build-up, consolidation and shedding of deposit begins. These are extremely complex, interaction phenomena, involving both physical and chemical aspects. This is the subject of Module 6 (Deposit Build-Up, Consolidation and Shedding), which also covers practical experiences in performing deposit measurements in full-scale.
Name:High-Temperature Cl-Corrosion
Description:One of the consequences of deposit formation is the possible chemical interaction between the deposit and the heat transfer tube, better known as corrosion, which is outlined in Module 7 (High-Temperature Cl-Corrosion), based on several years of research in this field at our Department at DTU. Aspects of corrosion underneath deposits formed in biomass- as well as waste-fired units are covered in details.
Name:Use of additives to Minimize Deposit Formation and High-Temperature Corrosion
Description:There are a number of ways to minimize corrosion, aerosol and ash deposit formation in boilers, one of them being the use of additives to affect the chemistry in the freeboard of the boiler, thereby minimizing e.g. the concentration of Cl in the inner layers of the deposit, or, minimizing the mass loading of aerosols and thereby the environmental impact of these. This has for years been a major research activity at DTU and Module 8 (Use of additives to Minimize Deposit Formation and High-Temperature Corrosion) therefore deals with the application of additives, both the classical Al-Si- and the more sophisticated S-based additives.
Name:Danish Case-Studies on Ash and Deposit Formation
Description:Finally, Module 9 (Danish Case-Studies on Ash and Deposit Formation) in this MOOC deals with Danish case studies of ash and deposit formation in utility boilers. The module covers three classical cases from dedicated straw-fired grate units: the Haslev/Slagelse, Rudkøbing and Masnedø CHPs. After this, an introduction to the MKS1 demoprogramme on co-firing of coal and straw in pc-fired units follow, this campaign marked a progressive step toward the ultimative shift from pure biomass-firing in grate units, to biodust-firing in pf-units. The last two lessons in this module covers biodust-firing at the Avedøre Power Station, with special focus on aerosol and deposit formation and chemistry, with and without the use of coal fly ash as an additive.
The basic idea behind this MOOC, is to present recent data on fuel characterization, slagging, fouling, corrosion, and trace element transformations, in a course that can be readily provided for students and industry people. This ensures understanding and application of the research, and provides the students and industry with a forum for discussion of the very latest research results, as well as feedback from industry to the research group at DTU, on important new research subjects in the field. The specific aim of the MOOC, is that students will be able to; Explain basic physical and chemical differences between solid fuels like coal, biomass, waste etc., be able to characterize solid fuels, and to interpret fuel analyses of them Interpret and utilize data from advanced fuel and ash analyses (SEM, DTA/TGA, chemical fractionation, ash melting temperatures) Describe chemically and physically, how critical ash-forming elements are released to the gas phase, the mechanisms for formation of aerosols and fly ash particles, and explain how ash is transported from bulk gas to heat transfer surfaces Quantify the processes of deposit build-up, sintering and shedding Explain the fundamentals of high-temperature corrosion in thermal fuel conversion systems Can calculate viscosities as a function of temperature and composition, temperature profiles in a deposit, rates of deposit build-up and sintering, as well as porosity changes vs. time.
