A Modular Approach to Sustainability Assessment and Decision Support in Chemical Process Design

Abstract

In chemical and allied industries, process design sustainability has gained public concern in academia, industry, government agencies, and social groups. Over the past decade, a variety of sustainability indicators have been introduced, but with various challenges in application. It becomes clear that the industries need urgently practical tools for conducting systematic sustainability assessment on existing processes and/or new designs and, further, for helping derive the most desirable design decisions. This paper presents a systematic, general approach for sustainability assessment and design selection through integrating hard (quantitative) economic and environmental indicators along with soft (qualitative) indicators for social criteria into design activities. The approach contains four modules: a process simulator module, an equipment and inventory acquisition module, a sustainability assessment module, and a decision support module. The modules fully utilize and extend the capabilities of the process simulator Aspen Plus, Aspen Simulation Workbook, and a spreadsheet, where case model development, data acquisition and analysis, team contribution assessment, and decision support are effectively integrated. The efficacy of the introduced approach is illustrated by the example of biodiesel process design, where insightful sustainability analysis and persuasive decision support show its superiority over commonly practiced technoeconomy evaluation approaches.

Development of Chemical Process Design and Control for Sustainability

“…In order to offer a more comprehensive and quantitative description of environmental, social and economic effects, the U.S. EPA has proposed a tool called GREENSCOPE [21] (Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a multi-Objective Process Evaluator) to support decision makers when developing, designing and evaluating sustainable processes and products. The GREENSCOPE tool allows for quantifying process sustainability and life cycle inventory (LCI) generation with about 140 indicators in four main areas: material efficiency (26), energy (14), economics (33) and environment (66). These indicators are capable of transmitting and translating process performance, feedstocks, utilities, equipment and output information into a sustainability measurement scale.…”

“…Recently, a modular approach for sustainable chemical process design was developed through the integration of quantitative economics and environmental indicators with qualitative indicators in social aspects [14]. Compared to the aforementioned methods, multi-objective optimization schemes have a higher potential to obtain the optimal trade-off between conflicting economic and environmental objectives.…”

Prioritization of bioethanol production pathways in China based on life cycle sustainability assessment and multicriteria decision-making

“…Thus, LCC indentifies the economics over the product life cycle. In addition to the traditional LCC methodologies, there are many other life cycle perspective economic indices, such as net present value (Ong et al 2012), discounted cash flow rate of return (Othman et al 2010), and breakeven year (Foolmaun and Ramjeawon 2012). LCC is used to determine the economic criteria for sustainability assessment.…”

Revealing values in a complex environmental program: a scaling up of values-based indicators

“…Diverse sustainability assessment initiatives, from buildings (Bragança et al, 2010) and manufacturing (Othman et al, 2010) to natural resource management and city-level sustainability assessment (RFSC, 2013), have incorporated 'soft' or qualitative indicators that arguably reflect very different values and worldviews from those underpinning the standard economic model.…”