Exergy Analysis of Food Drying Processes

Abstract

It is well known that micro-level system parameters may have some great impact on macro-level energy aspects, the environment, and sustainability. Of course, if one wants to approach these thermodynamically, there are two ways: energy analysis through the first law of thermodynamics and exergy analysis through the second law of thermodynamics. Exergy analysis is an essential tool to expose the impacts of a power generating device on exergy-based sustainability; sustainability is necessary to overcome current ecological, economic, and developmental problems (Dincer and Rosen, 2005). In this regard, some new exergy-based sustainability parameters for a PEM fuel cell have been developed and studied parametrically to investigate how they will help measure the level of environmental impact and sustainable development (Midilli and Dincer, 2009). These types of parameters may also be applied to other energy-related systems.Drying has been used worldwide for centuries to preserve different food and agricultural products. Nowadays, the drying process is one of the major procedures of food preservation. The basic target of food dehydration is to remove water to a final concentration, which assures microbial spoilage of the product and minimizes chemical and physical changes of the food during storage (Crapiste and Rotstein, 1997). Drying is an energy-intensive operation consuming 9-25% of national energy in the developed countries (Mujumdar, 1995). In many practical applications, drying is a process that requires high-energy input because of the high latent heat of water evaporation and relatively low-energy efficiency of industrial dryers.For development of sustainable energy, three important technological changes have been required: energy economies on the demand side, efficiency improvements in the energy production, and renewing of fossil fuels by various sources of renewable energy.

A resource efficiency assessment of the industrial mushroom production chain: the influence of data variability

“…The fundamental laws of thermodynamics for assessing the sustainability of food production are objective beyond dispute, they can be used to identify the causes of inefficiencies in the use of material and energy, and they can help in designing food production chains in a more sustainable manner. An objective tool for assessing the sustainability of food production chains that is based on the second law of thermodynamics is exergy analysis (Apaiah et al, 2006;Berghout et al, 2015;Colak et al, 2010;Dincer, 2011;Draganovic et al, 2013;Jankowiak et al, 2014;Zisopoulos et al, 2015a) where all input resources (e.g. raw materials, energy) are considered in terms of useful work (exergy).…”