Anastasios Moumtzakis

Windows are responsible for significant amounts of energy loss through typical building envelopes. There have been multiple studies on heat loss through the glazing unit and frame system. This study presents an experimental investigation of a window unit and focuses specifically on the conductance between the structural elements and the frame system of a conventional house in the city of Xanthi, northern Greece. It is obvious that even a perfect window system cannot reduce heat transfer between the base of the frame and the upper surface of the floor. The experimental and simulation procedure of this project includes the installation of an insulating layer in front of the window unit for a variety of frames (solid wood, aluminum, PVC, etc.) at different distances. The main objective of this paper is to determine how effective an insulating barrier can be in respect to different types of frame, glazing, and weather conditions for the control of heat loss. Through the application of this technique, in combination with an appropriate insulating frame and window unit, designers can control the temperature inside the room at close proximity to the windows, in order to contribute to energy saving, aiming towards a building with zero energy demand.

In the present work, the decolorization treatment of colored wastewaters produced from polyamide textile dyeing is studied using the electrocoagulation process with sacrificial aluminum electrodes. The electrical energy is obtained from a solar photovoltaic array by directly connecting it to the electrocoagulator without batteries. The photovoltaic electrocoagulation (PV-EC) system is made versatile according to the instantaneous solar irradiation by adjusting the wastewater flow rate to the current intensity supplied by the photovoltaic array. All the PV-EC experiments were performed in Kavala Institute of Technology (latitude 40°55′, longitude 24°22′, and altitude 138 m above the sea level). The purpose of this paper is to investigate all parameters affecting the efficiency of the process, such as initial wastewater pH, conductivity, operating time, flow rate, and solar irradiation. The efficiency of the EC process was followed by measurements of turbidity and chemical oxygen demand (COD). According to the obtained experimental results, fast and effective decolorization of the treated wastewater occurred in a few minutes of electroprocessing. Turbidity was quantitatively reduced from 103 to 0.2 NTU, amounting to a removal percentage of over 99%, whereas COD was reduced by 65%. The proposed process is appropriate for decolorizing colored textile dye wastewaters and especially for small applications in remote and isolated locations without connection to public electric grid.