A Novel Approach to the Optimal Design of Hybrid Waste-Recovery Processes

危险废物最小化是指减少在处理、储存或处置危险废物之前产生的危险废物。它是防止向环境中释放有害物质的有效方法。解决废物最小化问题的一个有效方法是使用现场回收/再利用分类网络。除了有利的环境影响外，采用这种废物回收方法还可以提供一种经济上有吸引力的废物管理替代方案。它可以节省大量的能源和原材料，并可能从可销售的废物中获得收入。随着每年超过2.5亿吨的危险废物被处置在全美各地的产生地点，废物回收/再利用的主张正在成为一种可取的工业实践。该项目的目标是为混合废物回收网络的优化设计设计一种新的方法。这项任务涉及开发实用工具，对许多潜在的废物分离系统以及蒸馏和质量交换等更经典的系统进行系统整合和筛选。该问题将被描述为一个最优网络综合任务，其目标是使系统的年化总成本最小化，同时实现分配的所有减少废物的任务。这个公式嵌入了所有感兴趣的潜在工艺备选方案，并提供了将该设计任务作为优化问题提出的工具。这一问题的解决方案确定了用于特定废物回收任务的分离过程的最佳组合、安排、类型、大小和操作条件。这一方法将通过三个有代表性的案例来阐述：渗透汽化网络的合成、反渗透系统和反渗透-质量交换混合过程。

Hazardous-waste minimization means the reduction of hazardous waste that is generated prior to its treatment, storage or disposal. It represents an efficient method for preventing the release of hazardous substances to the environment. An effective way of tackling waste-minimization problems is through the use of on-site recycle/reuse separation networks. In addition to its favorable environmental impact, the adoption of this waste-recovery approach can provide an economically attractive waste-management alternative. It can lead to significant energy and raw-materials savings and possibly provide income from the salable wastes. With more than 250 million tons of hazardous wastes disposed of at the generating sites throughout the United States annually, the proposition of waste recycle/reuse is becoming a desirable industrial practice. The objective of this project is to devise a new methodology for the optimal design of hybrid waste-recovery networks. This task involves the development of practical tools for the systematic integration and screening of the numerous potential waste-separation systems as well as more classical ones such as distillation and mass exchange. The problem will be formulated as an optimal-network synthesis task with the objective of minimizing the total annualized cost of the system while achieving all the assigned waste-reduction duties. This formulation embeds all the potential process alternatives of interest and provides a tool for posing this design task as an optimization problem. The solution of this problem identifies the optimal combination, arrangement, types, sizes and operating conditions of the separation processes to be employed for a given waste-recovery task. This approach will be elucidated via three representative cases: the synthesis of pervaporation networks, reverse- osmosis systems, and reverse-osmosis-mass-exchange hybrid processes.