REVIEW | doi:10.20944/preprints202209.0168.v1
Subject: Engineering, Civil Engineering Keywords: Keywords: Circular economy; building sector; Europe
Online: 13 September 2022 (10:04:31 CEST)
This article evaluates Europe's building sector's circular economy (CE). This industry is respon-sible for 42% of energy consumption, more than 50% of extracted materials, 30% of Europe's wa-ter and waste generation, and 35% of greenhouse gas (GHG) emissions. This study focuses on peer-reviewed articles from Scopus and Web of Science databases. Of the first 1750 publications, 2.9% were eligible for a full-text reading and analysis. Most of the trending studies, 92%, pro-mote the circular economy concept through construction materials rather than analyzing the im-pact of the construction sector on the environment and finding solutions for better implementa-tion, and 41% promote recycling and reuse as the only options. New Design solutions are in 12% of the studies, six-fold more than Law and Legislation, only 2%. Finding an optimal combination of assessing the life cycle of buildings and components and searching for different ways of man-aging the Construction and Demolition Waste at end-of-life is between 33% and 39%. Ultimately, one evaluated CE proposed frameworks for the building industry based on 10R principles varia-tions. One presents an alternative framework for a circular strategy for the building industry that focuses on Upcycling, replacing the Recover principle.
ARTICLE | doi:10.20944/preprints201907.0281.v2
Subject: Engineering, Industrial And Manufacturing Engineering Keywords: algorithm; heat-pump; drying; food; design; optimization
Online: 17 September 2019 (15:27:08 CEST)
Drying food involves complex physical atmospheric mechanisms with non-linear relations from the air-food interactions and those relations are strongly dependent on the moisture contents and the type of food. Such dependence makes it complex to design suitable dryers dedicated to a single drying process. To streamline the design of a novel compact food-drying machine, a heat pump dryer component design optimization algorithm was developed as a subprogram of a Computer Aided Engineering tool. The algorithm requires inputting food and air properties, the volume of the drying container and the technical specifications of the heat-pump off-the shelf components. The heat required to dehumidify the food supplied by the heat exchange process from condenser to evaporator, and the compressor’s requirements (refrigerant mass flow rate and operating pressures) are then calculated. Compressors can then be selected based in the volume and type of food to be dried. The algorithm is shown via a flow chart to guide the user through 3 different stages: Changes in drying air properties, Heat flow within dryer and Product moisture content. Example results of how different compressors are selected for different type of produces and quantities (Agaricus Blazei mushroom with 3 different moisture contents or fish from Thunnini tribe) conclude this article.