Transporting liquid waste is a continuously growing activity in several industries. This transportation is made in trucks and sea containers. Often, the liquid transported contains Volatile Organic Compounds (VOC) and odours. The process of washing and cleaning the truck tanks usually involves the emission of odours and VOCs. The aim of this study was to evaluate the odour abatement efficiency of a multistage hybrid approach consisting of alkaline scrubbing, condenser, adsorption with impregnated Al2O3 + active carbon (AC), and the injection of a deodorizing product to abate odour and VOC emission. In addition, the second aim of this study was to show that the use of these sequential technologies reduce VOC emissions below the limit of 100 mg/m³ set in the environmental authorisation.

   Before the abatement system was installed, VOC concentration was measured over a week averaging 200 mg/Nm³. After the installation of the abatement system, the results showed that the average VOC concentration was always well below the legal limit. In addition, when washing activities took place, the odour concentration measured at the inlet, and outlet of the abatement system was 5000 ouE/m3 and 150 ouE/m3, respectively. This was a 97% odour abatement efficiency.

   Water resources recovery facilities (WRRFs) are sources of direct emissions of greenhouse gases (GHGs) and volatile organic compounds (VOCs) produced by biological processes and indirect GHG emissions due to the energy consumed to operate the plant. The direct emissions also contribute to odour issues of WRRFs. Aeration of the biological tanks accounts for 50-60% of the total energy consumption of a WRRF and is therefore the major source of indirect GHG emissions.

   The optimized management of oxidation processes is consequently associated with environmental and economic benefits. The innovative solution proposed in this study consists of an automated self-moving prototype (LESSDRONE) for real-time monitoring of oxygen transfer efficiency (OTE) and of GHG emissions from the aerated tanks during operation, and a protocol for converting LESSDRONE measures and specific WRRF data into actions aimed at minimizing carbon footprint (CF) and energy demand.

   Since this month November 2022, GRAL dispersion model presents a new website: The Graz Lagrangian Model - GRAL - was initially developed in 1999 at the Institute of Thermodynamics and Sustainable Propulsion Systems at Graz University of Technology.

   In addition, new features and bugfixes have been implemented in the new GRAL Version 22.09, which is now available on the GRAL homepage.

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