PT21 Environmental Assessment, Environmental Toxicology
Exhibit Hall
8:00 AM - Tuesday
(PT308) Methodology for Environmental diagnosis using Life Cycle Techniques: application to Ethylene Oxide Process.
Yrigoyen-González, H.1, Castells, F.1, Jiménez, L.2, 1 Universitat Rovira i Virgili, Tarragona, Tarragona, Spain2 Universitat de Barcelona, Barcelona, Barcelona, Spain
ABSTRACT- The environmental assessment has several objectives as preserving natural resources, minimizing pollution and saving energy. These aspects have environmental and economical sense, hence a methodology must be developed to show the benefits related to these issues. Following this deliberation, a methodology and a tool consisting on five levels were created. The Ethylene Oxide process using air and oxygen as raw material was selected to validate the method. Parallel or series reactors are the used configurations. At first level, the necessary information is obtained using a simulator; subsequently this data is transferred to a spreadsheet through an interface. Once all the information is sent, the compounds related to secondary processes are added to the main spreadsheet, the flows are normalized to the functional unit and the eco-vector is generated (Second Level). The third level corresponds to the effect evaluation, impact categories are used to predict the potential impact related to the process. Air, soil and water are the analyzed fates. An economical evaluation is integrated to the environmental assessment in the fourth level. The main economical measurements are calculated (net present value, payback period, and internal rate of return, among others). The last level is the optimization. Both the process conditions and economical assessment are to be improved. Two objectives functions are established: one for the operational conditions and other one for the economical assessment (considering external and external costs). The minimization of cost related to the better environmental behavior is the goal in this level. The best process configuration with the lowest environmental impact is obtained using air as raw material and reactors in series. Different topologies can be analyzed to select the best option, and any change in an existing flow or operating conditions generates a new profile to be evaluated.
Key words: integration, environmental assessment, life cycle, optimization