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Biodrying consists of reducing moisture by using the heat from aerobic bio-degradation. The parameters that control the process are: aeration, temperature during the process, initial moisture of biowaste, and temperature and relative humidity of the input air. Lawn mowing and garden waste from the gardens of the University Jaume I, Castellón (Spain) were used as a substrate. Biodrying was performed in 10 reactors with known air volumes from 0.88 to 6.42 L/(min·kg dry weight (dw)). To promote aeration, 5 of the reactors had 15% of a bulking agent added. The experiment lasted 20 days. After the experiments it was found that the bulking agent led to greater weight loss. However, the increased airflow rate was not linearly proportional to the weight loss.

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Abstract:Biodrying is a process that consists in reducing the moisture content and stabilizing organic compounds to obtain a useful product, such as a fuel, or as a previous step to landfilling. This is achieved by using the heat generated in the aerobic fermentation of organic compounds. The main parameters that control the process are aeration, the temperature reached in fermentation, and the initial level of moisture. In this work, the substrate was composed of agricultural harvest and gardening waste from an area in the east of Spain.The biodrying process was carried out in a greenhouse, where both the heat generated in the fermentation and the heat of the sun were used. In order to promote aeration, two factors were taken into account: one was the capacity of the shredded prunings to act as a bulking agent and the other one was a perforated floor, which allowed air to pass through. An air outlet was installed at the top of the greenhouse to promote the "chimney effect". With this setup, drying times of 12 to 30 days were achieved (depending on the month), together with volume reductions greater than 50%. The time of the trial has been assess when the waste has received 75 kW/m 2 . The final waste with a low level of moisture (7 -15%) had a heating value suitable for use as fuel (around 15,000 kJ/kg).

Waste from construction and demolition activities represents one of the highest volumes of waste in Europe. 500 million tonnes are produced throughout the whole EU every year. In some EU members like Spain, approximately 83 per cent of such waste is disposed in landfills. The remaining part is classified and processed in treatment facilities so that it can later be used as recycled aggregates in the construction sector (sand, gravel, aggregates, etc.) but without much commercial success. The aim of this study is to use recycled aggregates from inert wastes (IW) in the different phases of a landfill (construction, operation and closure) with the aid of a new computer tool called LABWASTE.14. This tool incorporates the mathematical relationship among the activities of the landfill and provides as a result the economic viability of using recycled aggregates compared to aggregates from quarries.Therefore, knowing the needs of aggregates in landfills (dams, drainage layers, covering layers, collection wells, etc.) may determine the amount of IW that could be recovered. These 2 calculations can be obtained from some of the data that is introduced (population, land physiography, etc.). Furthermore, the use of LABWASTE.14 makes it possible to reduce the demand for aggregates from quarries. IntroductionConstruction and demolition wastes (CDW) are a growing problem in many countries. They account for large part of the waste generated in cities and they are usually placed in landfills (Ekanayake and Ofori, 2004). CDW represents around 31% of all waste produced in the European Union (EU) (Fisher and Werge, 2009). It is nowadays acknowledged that the consumption of raw materials in the construction industry is a non-sustainable activity. It is thus necessary to reduce this consumption, and the volume of CDW dumped, by using this waste as a source of raw materials for the production of recycled aggregates (Rodrigues et al., 2013). In fact, in many EU countries a very limited amount of CDW is recycled, the greatest portion being deposited or used as fill material (Masood et al., 2002). However, recycling concrete waste will lead to a reduction in valuable landfill space and savings in natural resources (Tabsh and Abdeltatah, 2009). Because of this, in the EU, the strategic plans about waste include CDW. The European Action Plan on the Circular Economy includes a number of actions that will target market barriers in specific sectors or material streams, such as construction and demolition wastes as well as horizontal measures in areas such as innovation and investment (EU, 2015). All these regulations establish the minimum requirements for their production and management, in order to promote prevention, reuse, recycling and recovery. The EU Waste Framework Directive (Directive 2008/98/EC) introduces recycling and recovery targets to be achieved by 2020 for household waste (50%) and construction and 3 demolition waste (70%). Furthermore, recycling CDW makes it possible to achieve considerable savings on energy and...