Abstract: Since 1990s along with the fast development of the computer technology and measurement instruments，the research of chemical engineering has been pushed progressively from the level of judgment by empirical regulations to the level of quantitative analysis by computer simulations. The research range of chemical engineering is extended to cover from observation and prediction of the micro-scale structure and interface to the system integration of the macro-scale equipment and plant. The principles and knowledge of chemical engineering are applied to from chemical engineering to process engineering for chemical conversion and physical transform such as in metallurgy, materials, energy source, environment, bioengineering. The scientists and engineers in chemical engineering profession are seeking the third mileage of the chemical engineering after the first mileage, unit operations, and the second mileage, transport process and chemical reaction engineering. The methodology of averaging, which is popularly used in chemical engineering, but neglects the influences of the heterogeneous multi-scale structure and interface, is the main reason of the large prediction error and the overwhelming difficulty in effective design and operation of chemical equipment. We should focus our attention on the structure, interface, and multi-scale issues, study the quantitative prediction theory and optimum control method for the multi-scale structure and interface, and establish the modeling for predicting the relationships among the multi-scale structure and interface, momentum transfer, heat transfer, mass transfer and chemical reaction. These efforts, combined with advanced calculating methods, computational fluid dynamics and computer simulation, may well solve the difficult problems in optimum control and scale-up of chemical processes and equipment, and catalyze the birth of the new mileage of chemical engineering.

Key words: structure, interface, multi-scale, flow, transport, chemical reaction, chemical engineering

摘要： 20世纪90年代以来，随着计算机技术和测量仪器的迅速发展，化学工程的研究水平日益提升，由经验规则的判断逐渐提高到计算机模拟量化分析. 化学工程的研究范围也日益扩大，下至纳微尺度结构与界面的观察与量化，上至宏观尺度设备与工厂的系统集成. 化学工程的服务对象也由化学工业扩展到冶金、材料、能源、环境、生物等诸多进行物质转化的过程工业. 目前化工科技界正在呼吁寻求继第一里程单元操作、第二里程传递过程和化学反应工程之后的第三里程. 化学工程中以往惯用的忽视非均匀多尺度结构和界面存在的平均方法是造成预测偏差和调控、放大困难的主要原因. 必须关注结构、界面和多尺度问题，研究多尺度结构、界面的量化预测理论和优化调控方法，建立多尺度结构、界面与"三传一反"的关系模型，与当代先进的计算方法、计算流体力学和计算机模拟相结合，有望解决化工过程与设备的优化调控与放大的难题，成为化学工程发展的新里程.

关键词: 结构, 界面, 多尺度, 流动, 传递, 化学反应, 化学工程