A general procedure for ecological and economic assessment during process design is presented. General objective functions to be used in the integrated development of fine chemical processes are defined. These are intended to accompany and guide process design from the very early design stages onward. The method uses three types of indices all based on simple mass balances. Mass balances are set up during the development, continually incorporating increasing complexity and knowledge. Correspondingly, mass-balance regions are extended from reaction to downstream processing and to waste treatment. Mass balances are systematically extended for multistep reactions. Mass-loss indices (MLI) are combined with ecological and economic weighing factors to yield environmental indices (EI) and economic indices (CI). Environmental indices are based on ABC-classification schemes related to environmental laws and regulations. Economic indices rely on raw material and waste treatment costs and may also include equipment and operating costs. These screening indices support condensed and lucid presentation and interpretation of mass-balance data and can be used as objective functions for the integrated development of chemical processes especially during the early design stage. Process examples are given in part 2 of this paper.

Process design in the chemical industry is challenged to integrate environmental and safety aspects in addition to economic and technical considerations in the early development phase of a new process. To achieve this goal, a flexible assessment framework of ecological and economic indices presented in part 1 of this paper is applied to two industrial case studies, one relying on purely chemical literature data and the other including early process knowledge. An allocation method for waste streams, components, and costs is presented and mass loss indices (MLI), cost indices (CI), and ecological indices (EI) are calculated. Using this index system, the ecological and economical problems of a process can be identified at their roots. Hence, this method supports the search for more cost-effective and environmentally friendlier chemical processes.