Forest fires are one of the commonest natural hazards. Forest fires make the largest contribution to CO2 emissions after the burning of fossil fuels. Here a new technology is proposed to extinguish forest fires not wi...Forest fires are one of the commonest natural hazards. Forest fires make the largest contribution to CO2 emissions after the burning of fossil fuels. Here a new technology is proposed to extinguish forest fires not with water, but with a slurry of serpentine. Serpentinites are abundantly available in many countries on every continent. If serpentine is calcined, it weathers very fast and captures CO2. Calcination, however, requires a lot of heat, which makes it counterproductive to produce calcined serpentine for CO2 capture. In cases, however, where heat is the problem, like in forest fires, one can extinguish them to greater advantage by using serpentinite slurries instead of plain water. The calcined residue that is left as a thin cake on the burning material prevents oxygen to reach the burning material. It also prevents the escape of inflammable gases, and the calcination itself withdraws large quantities of heat from the fire. After the fire is extinguished, the calcined material in contact with the atmosphere will rapidly weather and capture CO2. This compensates part of the CO2 that is produced by the fire. In tests, where the efficacy of quenching fires with serpentine slurries was compared to the effect of water, it turned out that serpentinite slurries performed far better.展开更多
为应对煤电行业碳排放压力,燃煤耦合生物质发电已成为实现煤电低碳转型的重要路径。深入解析煤与生物质热转化过程的反应机理,对于优化掺烧比例与污染物控制策略具有关键意义。系统综述了基于反应力场分子动力学(Reactive Force Field M...为应对煤电行业碳排放压力,燃煤耦合生物质发电已成为实现煤电低碳转型的重要路径。深入解析煤与生物质热转化过程的反应机理,对于优化掺烧比例与污染物控制策略具有关键意义。系统综述了基于反应力场分子动力学(Reactive Force Field Molecular Dynamics,ReaxFF MD)方法在该领域的研究进展,涵盖模型构建、热解与燃烧机理识别、污染物生成路径解析以及协同反应行为等关键内容。比较了典型煤与生物质结构模型的构建策略与适用范围,评估了不同分子结构与ReaxFF力场参数之间的匹配性,揭示模型物理真实度对模拟结果的影响;梳理了煤和生物质在热解及燃烧过程中CO、CO_(2)、NO_(x)等污染物的前驱体种类、自由基演化特征和反应路径;分析了共热解与掺烧体系中组分间的交联行为、非线性反应关系及掺烧比例变化对污染物排放的影响规律。在此基础上,总结了当前研究所面临的核心挑战,包括反应路径提取自动化水平不足、力场精度有限、模拟时间尺度与实际过程存在差异,以及宏微观参数映射机制不明等问题。进一步介绍了多尺度建模、机器学习辅助预测、GPU并行计算等新兴策略在煤-生物质热转化模拟中的应用探索。该研究为理解复杂碳-生物质热转化的微观机制提供理论依据,也为低碳清洁燃烧技术的优化与污染物精准调控提供数据支撑和方法指导。展开更多
文摘Forest fires are one of the commonest natural hazards. Forest fires make the largest contribution to CO2 emissions after the burning of fossil fuels. Here a new technology is proposed to extinguish forest fires not with water, but with a slurry of serpentine. Serpentinites are abundantly available in many countries on every continent. If serpentine is calcined, it weathers very fast and captures CO2. Calcination, however, requires a lot of heat, which makes it counterproductive to produce calcined serpentine for CO2 capture. In cases, however, where heat is the problem, like in forest fires, one can extinguish them to greater advantage by using serpentinite slurries instead of plain water. The calcined residue that is left as a thin cake on the burning material prevents oxygen to reach the burning material. It also prevents the escape of inflammable gases, and the calcination itself withdraws large quantities of heat from the fire. After the fire is extinguished, the calcined material in contact with the atmosphere will rapidly weather and capture CO2. This compensates part of the CO2 that is produced by the fire. In tests, where the efficacy of quenching fires with serpentine slurries was compared to the effect of water, it turned out that serpentinite slurries performed far better.
文摘为应对煤电行业碳排放压力,燃煤耦合生物质发电已成为实现煤电低碳转型的重要路径。深入解析煤与生物质热转化过程的反应机理,对于优化掺烧比例与污染物控制策略具有关键意义。系统综述了基于反应力场分子动力学(Reactive Force Field Molecular Dynamics,ReaxFF MD)方法在该领域的研究进展,涵盖模型构建、热解与燃烧机理识别、污染物生成路径解析以及协同反应行为等关键内容。比较了典型煤与生物质结构模型的构建策略与适用范围,评估了不同分子结构与ReaxFF力场参数之间的匹配性,揭示模型物理真实度对模拟结果的影响;梳理了煤和生物质在热解及燃烧过程中CO、CO_(2)、NO_(x)等污染物的前驱体种类、自由基演化特征和反应路径;分析了共热解与掺烧体系中组分间的交联行为、非线性反应关系及掺烧比例变化对污染物排放的影响规律。在此基础上,总结了当前研究所面临的核心挑战,包括反应路径提取自动化水平不足、力场精度有限、模拟时间尺度与实际过程存在差异,以及宏微观参数映射机制不明等问题。进一步介绍了多尺度建模、机器学习辅助预测、GPU并行计算等新兴策略在煤-生物质热转化模拟中的应用探索。该研究为理解复杂碳-生物质热转化的微观机制提供理论依据,也为低碳清洁燃烧技术的优化与污染物精准调控提供数据支撑和方法指导。
