Scale-up

放大
  • 文章类型: Journal Article
    2016年,巴西扩大了CriançaFeliz计划(PCF,来自葡萄牙语的首字母缩写),使其成为全球最大的幼儿发展(ECD)计划之一。然而,PCF未能实现其预期的影响。我们旨在确定在RE-AIM维度上实现PCF实施成果的障碍和促进者(达到,有效性或功效,收养,实施和维护)在COVID-19大流行期间。
    此比较案例研究分析根据人口规模选择了五个对比城市,该地区的国家,实施模型,以及实施PCF的时间长度。我们对PCF市政团队进行了244次采访(市政经理,supervisors,家庭访客),家庭,和跨部门专业人员。快速定性分析用于识别RE-AIM维度的主题。
    家庭对PCF目标的有限知识和信任是其实现的障碍。虽然PCF对育儿技能和ECD的感知好处使人们能够达到,缺乏解决社会需求的推荐协议,例如将粮食不安全的家庭与粮食资源联系起来,削弱了效力。关于社会援助部门是否应负责PCF的问题对其采用提出了质疑。COVID-19大流行加剧的实施障碍包括低工资,临时合同,高营业额,不经常监督,缺乏有效的监控系统,以及不存在或不运作的多部门委员会。缺乏制度化的资金是可持续性的挑战。
    复杂的相互交织的系统级障碍可能解释了PCF的不成功实施。巴西必须解决这些障碍,才能从PCF的巨大影响力及其所基于的循证护理原则中受益。
    NIH/NICHD。
    UNASSIGNED: In 2016, Brazil scaled up the Criança Feliz Program (PCF, from the acronym in Portuguese), making it one of the largest Early Childhood Development (ECD) programs worldwide. However, the PCF has not been able to achieve its intended impact. We aimed to identify barriers and facilitators to achieving the PCF implementation outcomes across the RE-AIM dimensions (Reach, Effectiveness or Efficacy, Adoption, Implementation and Maintenance) during the COVID-19 pandemic.
    UNASSIGNED: This comparative case study analysis selected five contrasting municipalities based on population size, region of the country, implementation model, and length of time implementing the PCF. We conducted 244 interviews with PCF municipal team (municipal managers, supervisors, home visitors), families, and cross-sectoral professionals. A rapid qualitative analysis was used to identify themes across RE-AIM dimensions.
    UNASSIGNED: Families\' limited knowledge and trust in PCF goals were a barrier to its reach. While the perceived benefit of PCF on parenting skills and ECD enabled reach, the lack of referral protocols to address social needs, such as connecting food-insecure families to food resources, undermined effectiveness. Questions about whether the social assistance sector should be in charge of PCF challenged its adoption. Implementation barriers exacerbated by the COVID-19 pandemic included low salaries, temporary contracts, high turnover, infrequent supervision, lack of an effective monitoring system, and nonexistence or non-functioning multisectoral committees. The absence of institutionalized funding was a challenge for sustainability.
    UNASSIGNED: Complex intertwined system-level barriers may explain the unsuccessful implementation of PCF. These barriers must be addressed for Brazil to benefit from the enormous reach of the PCF and the evidence-based nurturing care principles it is based upon.
    UNASSIGNED: NIH/NICHD.
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  • 文章类型: Journal Article
    背景:扩大规模和可持续性通常是分开研究的,很少有研究研究这两个过程之间的相互依赖性以及疟疾预防和控制创新的实施背景。研究人员和实施者对创新的内容给予了更多的关注,因为他们专注于技术层面和扩张条件。研究人员通常认为创新是线性序列,其中扩大规模和可持续性代表了最后阶段。在这份手稿中使用系统思维,我们通过2014年至2018年在布基纳法索采用和实施季节性疟疾化学预防措施(SMC),分析了复杂的规模和可持续性过程.
    方法:我们进行了一项定性案例研究,涉及141个回顾性次要数据(行政,按,科学,工具和登记册,和逐字记录)从2012年到2018年。我们用2018年2月至3月期间收集的主要数据补充了这些数据,这些数据是通过对SMC利益相关者和非参与者观察的15次个人半结构化访谈的形式收集的。过程分析使我们能够根据不同的垂直和水平分析水平及其相互联系,随着时间的推移概念化扩展和可持续性过程。
    结果:我们的结果表明,SMC的六个内部和外部决定因素可能对其规模扩大和可持续性产生负面影响或负面影响。这些决定因素是有效性,监测和评估系统,资源(财务,材料,和人类),领导和治理,适应当地环境,和其他外部元素。我们的结果表明,捐助者和执行行为者将财政资源优先于其他决定因素。相比之下,我们的研究清楚地表明,创新的可持续性,以及它的扩大,在很大程度上取决于对决定因素相互关联性的考虑。每个决定因素都可以同时构成创新成功的机遇和挑战。
    结论:我们的发现强调了系统观点在考虑所有环境(国际,国家,国家以下,和局部)实现质量的大规模改进,股本,以及全球卫生干预措施的有效性。因此,复杂和系统的思维使我们有可能观察到新兴和动态的创新行为以及可持续性和扩大过程的动态。
    Scale-up and sustainability are often studied separately, with few studies examining the interdependencies between these two processes and the implementation contexts of innovations towards malaria prevention and control. Researchers and implementers offer much more attention to the content of innovations, as they focus on the technological dimensions and the conditions for expansion. Researchers have often considered innovation a linear sequence in which scaling up and sustainability represented the last stages. Using systems thinking in this manuscript, we analyze complex scaling and sustainability processes through adopting and implementing seasonal malaria chemoprevention (SMC) in Burkina Faso from 2014 to 2018.
    We conducted a qualitative case study involving 141 retrospective secondary data (administrative, press, scientific, tools and registries, and verbatim) spanning from 2012 to 2018. We complemented these data with primary data collected between February and March 2018 in the form of 15 personal semi-structured interviews with SMC stakeholders and non-participant observations. Processual analysis permitted us to conceptualize scale-up and sustainability processes over time according to different vertical and horizontal levels of analysis and their interconnections.
    Our results indicated six internal and external determinants of SMC that may negatively or positively influence its scale-up and sustainability. These determinants are effectiveness, monitoring and evaluation systems, resources (financial, material, and human), leadership and governance, adaptation to the local context, and other external elements. Our results revealed that donors and implementing actors prioritized financial resources over other determinants. In contrast, our study clearly showed that the sustainability of the innovation, as well as its scaling up, depends significantly on the consideration of the interconnectedness of the determinants. Each determinant can concurrently constitute an opportunity and a challenge for the success of the innovation.
    Our findings highlight the usefulness of the systemic perspective to consider all contexts (international, national, subnational, and local) to achieve large-scale improvements in the quality, equity, and effectiveness of global health interventions. Thus, complex and systems thinking have made it possible to observe emergent and dynamic innovation behaviors and the dynamics particular to sustainability and scaling up processes.
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  • 文章类型: Journal Article
    考虑到工艺本身的技术挑战和高成本,冻干工艺的放大和转移仍然是非常具有挑战性的任务。本文第一部分讨论了放大和转移的挑战,包括商业规模冷冻过程中的小瓶破损,鳞片之间的蛋糕阻力差异,制冷能力差异的影响,和几何形状对干燥机性能的影响。这项工作的第二部分根据作者的经验讨论了扩大和转移方面的成功和不成功的做法。还概述了冻干过程的放大和转移的监管方面,包括有关干燥器等效性的主题。根据对挑战的分析和最佳实践的总结,提出了扩大和转移冻干过程的建议,包括对冷冻干燥领域这一领域未来发展方向的预测。还针对宽范围的小瓶容量提供了关于选择小瓶中的残余真空的建议。
    Scale-up and transfer of lyophilization processes remain very challenging tasks considering the technical challenges and the high cost of the process itself. The challenges in scale-up and transfer were discussed in the first part of this paper and include vial breakage during freezing at commercial scale, cake resistance differences between scales, impact of differences in refrigeration capacities, and geometry on the performance of dryers. The second part of this work discusses successful and unsuccessful practices in scale-up and transfer based on the experience of the authors. Regulatory aspects of scale-up and transfer of lyophilization processes were also outlined including a topic on the equivalency of dryers. Based on an analysis of challenges and a summary of best practices, recommendations on scale-up and transfer of lyophilization processes are given including projections on future directions in this area of the freeze drying field. Recommendations on the choice of residual vacuum in the vials were also provided for a wide range of vial capacities.
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  • 文章类型: Journal Article
    背景:低收入和中等收入国家需要扩大公共卫生干预措施,以确保公平和可持续的影响得到广泛认可。然而,对于项目如何在设计和实施其举措中寻求解决扩大规模的重要性,人们知之甚少。本文旨在深入了解加纳地区级卫生管理加强干预措施的促进者,马拉维和乌干达。
    方法:该研究采用了比较案例研究方法,进行了两轮数据收集(2019年和2021年),其中应用了不同的定性方法的组合。与地区进行了访谈和小组讨论,参与实施和扩大干预措施的区域和国家利益攸关方。
    结果:不同利益相关者之间关于如何将干预制度化到现有系统中促进扩大规模的共同愿景。还确定了冠军的重要性,因为它们影响关键决策者的买入,当决策者被说服时,扩大规模的政治和财政支持可以增加。在两个国家,一个特定的机会窗口促进了扩大规模。采取灵活的方法来扩大规模,允许根据具体情况调整干预和扩大战略,也被确定为推动者。权力下放的背景以及所涉及的利益相关者之间的政治和权力关系也影响了扩大规模。
    结论:尽管确定了扩大规模的促进者,在所有国家,将干预措施完全纳入卫生系统已被证明具有挑战性。从系统变更的角度进行规模扩大可能对未来的规模扩大工作有用,因为它侧重于大规模的可持续系统变革(例如改善地区卫生管理),方法是测试可能有助于预期变革的干预措施的组合,而不是横向扩展并试图在系统中嵌入一种特定的干预措施。
    BACKGROUND: The need to scale up public health interventions in low- and middle-income countries to ensure equitable and sustainable impact is widely acknowledged. However, there has been little understanding of how projects have sought to address the importance of scale-up in the design and implementation of their initiatives. This paper aims to gain insight into the facilitators of the scale-up of a district-level health management strengthening intervention in Ghana, Malawi and Uganda.
    METHODS: The study took a comparative case study approach with two rounds of data collection (2019 and 2021) in which a combination of different qualitative methods was applied. Interviews and group discussions took place with district, regional and national stakeholders who were involved in the implementation and scale-up of the intervention.
    RESULTS: A shared vision among the different stakeholders about how to institutionalize the intervention into the existing system facilitated scale-up. The importance of champions was also identified, as they influence buy-in from key decision makers, and when decision makers are convinced, political and financial support for scale-up can increase. In two countries, a specific window of opportunity facilitated scale-up. Taking a flexible approach towards scale-up, allowing adaptations of the intervention and the scale-up strategy to the context, was also identified as a facilitator. The context of decentralization and the politics and power relations between stakeholders involved also influenced scale-up.
    CONCLUSIONS: Despite the identification of the facilitators of the scale-up, full integration of the intervention into the health system has proven challenging in all countries. Approaching scale-up from a systems change perspective could be useful in future scale-up efforts, as it focuses on sustainable systems change at scale (e.g. improving district health management) by testing a combination of interventions that could contribute to the envisaged change, rather than horizontally scaling up and trying to embed one particular intervention in the system.
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  • 文章类型: Journal Article
    冷冻干燥过程的放大和转移仍然是复杂且不一致的实践。我们在这些论文中总结了低效和良好的实践,并提供了一些实用的建议。已证明,在实验室和商业规模的干燥机中使用相同的工艺设定点/时间可能会导致产品质量损失(塌陷或小瓶破裂)。新兴的建模方法展示了实际优势。然而,一些输入参数的前期生成(小瓶传热系数,最小可控压力,和最大升华速率)对于模型利用率至关重要。虽然初级干燥步骤可以高度可信地转移(例如,使用建模),二次干燥通常相当简单,预测冻结期间产品行为的潜在变化仍然具有挑战性。
    The freeze-drying process scale-up and transfer remain a complicated and non-uniform practice. We summarized inefficient and good practices in these papers and provided some practical advice. It was demonstrated that using the same process set points/times in laboratory and commercial scale dryers may lead to loss of product quality (collapse or vial breakage). The emerging modeling approach demonstrated practical advantages. However, the upfront generation of some input parameters (vial heat transfer coefficient, minimum controllable pressure, and maximum sublimation rate) is essential for model utilization. While the primary drying step can be transferred with a high degree of confidence (e.g., using modeling), and secondary drying is usually fairly straightforward, predicting potential changes in product behavior during freezing remains challenging.
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  • 文章类型: Journal Article
    评估:过去十年来,全球对全民健康覆盖(UHC)的承诺不断增加,引发了UHC启发的改革和投资,以扩大许多低收入和中等收入国家(LMICs)的卫生服务覆盖面。全民健康覆盖旨在确保所有人都能获得优质的医疗服务,当家庭成员生病时,保护他们免受公共卫生风险和自付医疗费用的贫困。
    UNASSIGNED:本文回顾了健康保险作为解决健康筹资问题的政策工具的作用,将其作为加快实现低收入国家全民健康覆盖的贡献机制。我们重点关注尼日利亚为其全体人口提供健康保险的法律框架,以及技术在促进健康保险计划注册方面的作用。
    UNASSIGNED:从2022年5月至7月,我们采用了一个横断面案例研究设计,结合:(i)对UHC的影响的文献综述与(ii)尼日利亚医疗保险系统的文献分析,和(iii)对健康保险数据集进行二次分析,以了解部署MedStrat的经验,本地开发的数字医疗保险管理系统,及其功能,支持尼日利亚多个州的健康保险计划管理。我们借鉴了当代技术采用模型,对从文献和文献综述以及健康保险数据集中分析的各种数据进行三角分析,以确定:(i)采用数字保险计划的推动者,(ii)数字技术对扩大获得健康保险的贡献,以及(Iii)数字保险干预的进一步可扩展性。
    UNASSIGNED:初步调查结果表明,数字保险管理系统可以帮助增加保险参保人数,尤其是在贫困家庭中。采用数字保险计划的三个背景因素是有利的政策环境,公私伙伴关系,以及持续的利益相关者参与和培训。
    UNASSIGNED:在尼日利亚和类似情况下成功扩展数字健康保险计划的关键要素包括:(i)易用性,(ii)支持电子保险系统的现有数字基础设施,和(Iii)通过数据加密体现的信任,维护所有数据的审计跟踪,和内置的欺诈预防流程。我们的发现肯定了数字健康技术可以在LMIC中实现UHC方面发挥作用。
    UNASSIGNED: Increasing global commitment to Universal Health Coverage (UHC) in the past decade has triggered UHC-inspired reforms and investments to expand health service coverage in many Low- and Middle-Income Countries (LMICs). UHC aims to ensure that all people can access quality health services, safeguard them from public health risks and impoverishment from out-of-pocket payments for healthcare when household members are sick.
    UNASSIGNED: This paper reviews the role of health insurance as a policy tool to address health financing as a contributory mechanism for accelerating the achievement of UHC in LMICs. We focus on Nigeria\'s legal framework for health insurance coverage for its whole population and the role of technology in facilitating enrollment to health insurance schemes.
    UNASSIGNED: From May to July 2022, we adopted a cross-sectional case study design combining: (i) a literature review of the effects of UHC with (ii) document analysis of health insurance systems in Nigeria, and (iii) secondary analysis of health insurance datasets to understand experiences of deploying MedStrat, a locally-developed digital health insurance management system, and its features that support the administration of health insurance schemes in multiple states of Nigeria. We drew on contemporary technology adoption models to triangulate diverse data analyzed from literature and documents reviews and from health insurance datasets to identify: (i) enablers of adoption of digital insurance schemes, (ii) the contribution of digital technology to expanding access to health insurance, and (iii) further scalability of digital insurance intervention.
    UNASSIGNED: Preliminary findings suggests that digital insurance management systems can help to increase the number of enrollees for insurance especially among poor households. Three contextual enablers of adoption of digital insurance schemes were a favourable policy environment, public-private-partnerships, and sustained stakeholder engagement and training.
    UNASSIGNED: Key elements for successful scaling of digital health insurance schemes across Nigeria and similar contexts include: (i) ease of use, (ii) existing digital infrastructure to support electronic insurance systems, and (iii) trust manifested via data encryption, maintaining audit trails for all data, and in-built fraud prevention processes. Our findings affirm that digital health technology can play a role in the attainment of UHC in LMICs.
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  • 文章类型: Journal Article
    干预测试阶段中干预的成本和收益可能与大规模实施和交付干预时所经历的成本和收益不同。然而,已经进行了有限的实证工作,以探索与实施和扩大规模相关的经济结构如何对干预成本产生影响。这项研究的目的是探索在II型转化研究试验中测试的健康体重和身体形象干预措施的实施和扩大的潜在经济影响。
    支持健康的形象,营养与运动(SHINE)研究是一项集群随机对照试验,旨在提供关于健康营养的普及教育,澳大利亚中学青少年的体育活动和健康行为。使用标准的微观成本计算技术在试验的同时收集干预成本的数据。与主要干预利益相关者进行了半结构化访谈,以探讨实施和扩大规模的潜在经济影响。两位作者进行了主题内容分析。
    15个干预组学校参加了2019年针对学生的为期8周的在线干预(99个7年级班级;2,240名学生)。助推器课程分别在2020年和2021年的8年级和9年级的一次课程中进行。根据试验,干预交付和协调的时间成本占干预成本的大部分(90%)。以及与干预培训和设备旅行相关的费用。与干预利益相关的主题来自对六个干预利益相关者的访谈,包括在线交付提供的规模经济潜力。可能对干预实施和规模产生影响的背景主题包括所有学校部门的可接受性,用于干预交付的IT基础设施的可用性和可靠性以及人口特征的变化。干预计划的许多关键变更对于支持和维持干预规模的扩大至关重要。此外,如果要大规模成功实施干预措施,则确定了重大的实施成本。
    这项研究的结果为III型实施试验的进展决策提供了重要信息。包括预算分配,并将为建模的经济评估提供信息。
    The costs and benefits of an intervention within the intervention testing phase may differ from those experienced when that intervention is implemented and delivered at scale. Yet limited empirical work has been undertaken to explore how economic constructs related to implementation and scale-up might have an impact on intervention cost. The aim of this study was to explore the potential economic impacts of implementation and scale-up on a healthy weight and body image intervention tested in a Type II translational research trial.
    The Supporting Healthy Image, Nutrition and Exercise (SHINE) study is a cluster randomised controlled trial, aiming to deliver universal education about healthy nutrition, physical activity and wellbeing behaviours to adolescents in Australian secondary schools. Data on the cost of the intervention were collected alongside the trial using standard micro-costing techniques. Semi-structured interviews were conducted with key intervention stakeholders to explore the potential economic impacts of implementation and scale-up. Thematic content analysis was undertaken by two authors.
    Fifteen intervention group schools participated in the 8-week online intervention targeting students in 2019 (99 Grade 7 classes; 2,240 students). Booster sessions were delivered during one class session in Grades 8 and 9, in 2020 and 2021 respectively. Time costs of intervention delivery and co-ordination comprised the majority (90%) of intervention cost as per the trial, along with costs associated with travel for intervention training and equipment. Themes related to the benefit of the intervention emerged from interviews with six intervention stakeholders, including the potential for economies of scale afforded by online delivery. Contextual themes that may have an impact on intervention implementation and scale included acceptability across all school sectors, availability and reliability of IT infrastructure for intervention delivery and variations in population characteristics. A number of key alterations to the intervention program emerged as important in supporting and sustaining intervention scale-up. In addition, significant implementation costs were identified if the intervention was to be successfully implemented at scale.
    The findings from this study provide important information relevant to decisions on progression to a Type III implementation trial, including budget allocation, and will inform modelled economic evaluation.
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  • 文章类型: Journal Article
    BACKGROUND: SMS for Life was one of the earliest large-scale implementations of mHealth innovations worldwide. Its goal was to increase visibility to antimalarial stock-outs through the use of SMS technology. The objective of this case study was to show the multiple innovations that SMS for Life brought to the Tanzanian public health sector and to discuss the challenges of scaling up that led to its discontinuation from a health systems perspective.
    METHODS: A qualitative case-study approach was used. This included a literature review, a document review of 61 project documents, a timeline of key events and the collection and analysis of 28 interviews with key stakeholders involved in or affected by the SMS for Life programme. Data collection was informed by the health system building blocks. We then carried out a thematic analysis using the WHO mHealth Assessment and Planning for Scale (MAPS) Toolkit as a framework. This served to identify the key reasons for the discontinuation of the programme.
    RESULTS: SMS for Life was reliable at scale and raised awareness of stock-outs with real-time monitoring. However, it was discontinued in 2015 after 4 years of a national rollout. The main reasons identified for the discontinuation were the programme\'s failure to adapt to the continuous changes in Tanzania\'s health system, the focus on stock-outs rather than ensuring appropriate stock management, and that it was perceived as costly by policy-makers. Despite its discontinuation, SMS for Life, together with co-existing technologies, triggered the development of the capacity to accommodate and integrate future technologies in the health system.
    CONCLUSIONS: This study shows the importance of engaging appropriate stakeholders from the outset, understanding and designing system-responsive interventions appropriately when scaling up and ensuring value to a broad range of health system actors. These shortcomings are common among digital health solutions and need to be better addressed in future implementations.
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  • 文章类型: Journal Article
    BACKGROUND: A new two-year Post University Specialty Training (PUST) programme in family medicine was introduced to improve the quality of postgraduate speciality medical education in Tajikistan. Postgraduate education of family doctors (FDs) needs to be urgently scaled up, as 38% of FD positions in Tajikistan remained unfilled in 2018. Moreover, the international financial support for the PUST programme is ending. This investment case assesses the minimum funding needed for the continuation and scale-up of PUST and establishes the rationale for the investment in the light of a recent evaluation.
    METHODS: The costs of the programme were calculated for 2018 and a scale-up forecast made for the period 2019-2023. The impact of the scale-up on the shortage of FDs was assessed. An evaluation using a Multiple Choice Questionnaire and Objective Structured Clinical Examination (OSCE) assessed and compared theoretical knowledge, clinical skills and competencies of PUST trained and conventionally trained FDs.
    RESULTS: The annual costs of the programme were US$ 228,000 in 2018. The total investment needed for scaling up PUST from 31 new FDs in 2018 to 100 FD graduates each year by 2023 was US$ 802,000.However, when the retirement of FDs and population growth are considered, the scale-up will result only in maintaining the current level of FDs working and not solve the country\'s FD shortage. The PUST FDs demonstrated significantly better clinical skills than the conventionally trained interns, scoring 60 and 45% of OSCE points, respectively. Theoretical knowledge showed a similar trend; PUST FDs answered 44% and interns 38% of the questions correctly.
    CONCLUSIONS: The two-year PUST programme has clearly demonstrated it produces better skilled family doctors than the conventional one-year internship, albeit some enduring quality concerns do still prevail. The discontinuation of international support for PUST would be a major setback and risks potentially losing the benefits of the programme for family medicine and also other specialities. To guarantee the supply of adequately trained FDs and address the FD shortage, the PUST should be continued and scaled up. Therefore, it is essential that international support is extended and a gradual transition to sustainable national financing gets underway.
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  • 文章类型: Journal Article
    背景技术水力空化(HC)正越来越多地用于广泛的应用中。与超声波空化不同,HC是可扩展的并且已经在大规模工业应用中使用。然而,在公开文献中没有关于量表对HC性能的影响的信息。在这项工作中,我们第一次出席,在四种不同尺度上使用HC降解水中复杂有机污染物的实验数据(按容量放大约200倍)。基于涡流的HC设备提供各种优势,如早期开始,空化产量高,堵塞和侵蚀倾向明显降低。在这项工作中,我们使用了基于涡流的HC设备。2,4二氯苯胺(DCA)-具有多个官能团的芳族化合物被认为是模型污染物。使用具有特征喉部尺寸的基于涡流的HC装置进行水中DCA的降解,dt为3,6,12和38mm,根据流量(1.3至247LPM)放大了几乎200倍。考虑到操作最大规模HC装置的实验限制,这里给出的实验数据只有一个值的压降穿过HC装置(280kPa)。扩展了以前使用的逐次降解模型,以描述本研究中使用的污染物的实验数据,并提出了一种通用形式。发现降解性能随着规模的增加而降低,然后随着平台的增加而降低。基于实验数据开发了适当的相关性。开发的方法和提出的结果为进一步开发HC设备的综合多尺度建模提供了良好的基础和数据集。
    Hydrodynamic cavitation (HC) is being increasingly used in a wide range of applications. Unlike ultrasonic cavitation, HC is scalable and has been used at large scale industrial applications. However, no information about influence of scale on performance of HC is available in the open literature. In this work, we present for the first time, experimental data on use of HC for degradation of complex organic pollutants in water on four different scales (~200 times scale-up in terms of capacity). Vortex based HC devices offer various advantages like early inception, high cavitational yield and significantly lower propensity to clogging and erosion. We have used vortex based HC devices in this work. 2,4 dichloroaniline (DCA) - an aromatic compound with multiple functional groups was considered as a model pollutant. Degradation of DCA in water was performed using vortex-based HC devices with characteristic throat dimension, dt as 3, 6, 12 and 38 mm with scale-up of almost 200 time based on the flow rates (1.3 to 247 LPM). Considering the experimental constraints on operating the largest scale HC device, the experimental data is presented here at only one value of pressure drop across HC device (280 kPa). A previously used per-pass degradation model was extended to describe the experimental data for the pollutant used in this study and a generalised form is presented. The degradation performance was found to decrease with increase in the scale and then plateaus. Appropriate correlation was developed based on the experimental data. The developed approach and presented results provide a sound basis and a data set for further development of comprehensive multi-scale modelling of HC devices.
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