Technological-ecological networks for sustainable process design

In traditional process design, engineers aim to use man-made technology to solve practical problems. However, the resulting designs are often directly or indirectly dependent on ecosystem goods and services and this is often ignored. Neglecting these invaluable services has led to unsustainable practices through overexploitation of ecosystems. In addition, narrowly focusing on technological solutions unnecessarily prevents engineers from turning to nature as an option in process design. This paper proposes integrating technological systems and their corresponding ecological systems in process design. These technological-ecological networks (TEco-Nets) mimic the way nature operates by having closed material and energy streams, or in other words, ldquowaste = foodrdquo. Such networks would be a step towards true sustainability. However, ecological and technological systems are usually outside the area of expertise of engineers and ecologists, respectively. Therefore, integrating the two disciplines would be challenging yet potentially fruitful. In this study, the concept of TEco-Nets is illustrated through a qualitative example of a sugarcane refinery as well as quantitative case study of a residential system. The residential system example indicates that the carbon carrying capacity of the associated ecosystems is overwhelmed under traditional operating conditions. However, modifying the design of the technological and ecological systems helps alleviate this and indicates that residential systems could operate closer to sustainability in terms of carbon. This example suggests that TEco-Nets may be beneficial in larger scale industrial process design problems.