Deposition of ash and its effect on heat transfer during the oxy-combustion of biomass and biomass-coal blends.

1603249 Wendt，Jost该项目的总体目标是提供信息，使生物质和生物质-煤混合物的富氧燃烧能够用于发电。这项技术在进行碳封存之后，有可能产生重大影响，因为它可以同时发电和减少二氧化碳排放，基本上使用传统设备。这个过程需要了解生物质富氧燃烧条件下的灰沉积和传热，这是本研究的两个重点。国际团队由美国的犹他州大学（UU）和北达科他州大学（UND）以及中国的华中科技大学（HUST）和东南大学（SEU）组成。科学目标是：1）验证生物质-煤混合物富氧燃烧期间灰分沉积速率的预测;以及2）了解这些如何影响锅炉室辐射。基于有限的初步实验工作的假设是，灰沉积速率与烟道气中的亚微米颗粒（PM 1）的浓度呈线性关系。在将工作扩展到含氧生物质燃烧时，试图了解受控灰沉积物的内结合层和主体层的形成，并开发和应用实验信息来改进现有模型，以预测灰层的建立和亚微米气溶胶的形成。这些模型将与高保真度辐射特性模型一起用于燃烧情景的计算流体动力学模拟。这些模拟将通过在美国和中国进行的各种规模的协调实验进行验证，涵盖各种燃料，涵盖一系列燃烧条件，包括在大气和加压富氧燃烧条件下的实验验证。该国际合作项目旨在提供基础知识，帮助将该技术应用于第一代（大气压）和第二代（高压）富氧燃烧技术。一名美国研究生将协助在中国的一些实验，而中国学生将参加美国的活动。

1603249 Wendt, Jost The overall objective of this project is to provide information that will enable implementation of oxy-combustion of biomass and biomass-coal blends for power generation. This technology, when followed by carbon sequestration, has the potential to have significant impact because it can simultaneously produce electricity and decrease CO2 emissions, using essentially conventional equipment. This process requires a knowledge of ash deposition and heat transfer under biomass oxy-combustion conditions, which are the twin thrusts of this research. The international team assembled consists of the Universities of Utah (UU) and North Dakota (UND) in the US and Huazhong University of Science and Technology (HUST), and Southeastern University (SEU) in China. Scientific objectives are to: 1) validate predictions of ash deposition rates during the oxy-combustion of biomass-coal blends; and 2) understand how these impact boiler chamber radiation. The hypothesis, based on limited preliminary experimental work, is that ash deposition rates are linearly dependent on the concentration of sub-micron particles (PM1) in the flue gas. In extending the work to oxy-biomass combustion, it is sought to understand formation of both the inner binding layer and bulk layer of controlled ash deposits, and to develop and apply experimental information to refine existing models for predicting the ash layer build up and submicron aerosol formation. These models will be employed in conjunction with high fidelity radiative property models in computational fluid dynamic simulations of the combustion scenarios. The simulations will be validated through coordinated experiments in both the US and China, at various scales, for various fuels, covering a range of combustion conditions, including experimental validation at both atmospheric and pressurized oxy-combustion conditions. This international collaborative project is expressly designed to provide the fundamental knowledge that will help bring this technology into practice, for both first generation (atmospheric pressure) and second generation (elevated pressure) oxy-combustion technologies. A US graduate student will assist in some of the experiments in China while Chinese students will participate in US activities.