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Foamed glass is a lightweight material mainly used for thermal insulation in the construction and chemical industry. Its excellent combination of properties is related to closed pores filled with CO2 gas and low density (i.e. high porosity). In order to obtain superior insulation properties several parameters need to be tuned in relation to the composition of the glass used for the synthesis. For acoustic insulation, however, open porosity is preferred. Despite straightforward application in acoustics the reports on this aspect are scarce. In this contribution, we present the results of our work focused on development of closed and open porous foamed glass for thermal and acoustic insulation. Open and closed-porous foamed glasses were prepared from cullets of different chemical composition. For closed-porous samples CRT-panel glass was used, while for open-porous samples bottle glass was used. The closed and open porosity of both samples was further tuned by specific additives for adjusting surface tension or crystallization. Thus we were able to prepare samples with 95 % closed or open porosity at a density of 100–120 kg/m3. The synthesis, and thermal and acoustic properties will be discussed.

Glass foams are light weight cellular glasses with many applications in civil engineering and the petrochemical industry. A mix of properties such as low thermal conductivity, high strength and closed porous structure make the glass foam an attractive thermal insulating material. The thermal conductivity is a key parameter of glass foam performances since energy saving is increasingly important for our society and climate. Through the production process, glass foams with controlled chemistry can be created, giving the possibility to understand the heat transport mechanism and, thereby, to optimise the production condition to lower the thermal conductivity. In this presentation, we review recent work on the thermal properties of glass foams, with focus on the heat transport through the glass foam. We demonstrate the importance and ways of controlling gas composition and glass chemistry in respect to foam structure, crystallinity and bulk conductance. Some design criteria for producing low conducting glass foam will be outlined. Glass foams are light weight cellular glasses with many applications in civil engineering and the petrochemical industry. A mix of properties such as low thermal conductivity, high strength and closed porous structure make the glass foam an attractive thermal insulating material. The thermal conductivity is a key parameter of glass foam performances since energy saving is increasingly important for our society and climate. Through the production process, glass foams with controlled chemistry can be created, giving the possibility to understand the heat transport mechanism and, thereby, to optimise the production condition to lower the thermal conductivity. In this presentation, we review recent work on the thermal properties of glass foams, with focus on the heat transport through the glass foam. We demonstrate the importance and ways of controlling gas composition and glass chemistry in respect to foam structure, crystallinity and bulk conductance. Some design criteria for producing low conducting glass foam will be outlined.

Zunächst werden existierende Lösungen für die Vermessung und Überwachung von Schächten vorgestellt, insbesondere kinematische Vermessungssysteme. Solche Systeme sind vor allem für moderne Hochleistungsbergwerke von großer Bedeutung, da hier eine permanente Verfügbarkeit der Schächte über 24 h an 7 Tagen der Woche Voraussetzung für den wirtschaftlichen Erfolg sind. Daher haben die Betreiber ein großes Interesse an kostengünstigen, zeitsparenden und sicheren Verfahren zur Schachtvermessung und -überwachung sowie zur Zustandsinspektion, einschließlich erforderlicher Wartungsar- beiten. EinbesonderesAugenmerkgiltdabeiden behördlichenAn- forderungen an die vorgeschriebenen Überwachungen und Inspektionen aufgrund der geltenden gesetzlichen Regeln und behördlichen Zulassungen. Aufgrund dieser hohen Anforderungen wurde im Rahmen des Europäischen Innovationsnetzwerks EIT RawMaterials das Projekt iDeepMon zur Förderung ausgewählt. Das Pro- jektteam mit industriellen und universitären Partnern aus Deutschland, Österreich, Polen und Schweden entwickelt zurzeit auf Basis der genannten existierenden Schachtvermessungssysteme den Prototyp eines weitgehend automatisierten Systems zur regelmäßigen Schachtinspektion, das langfristig ein integrierter Bestandteil eines umfassenden Kontrollprozesses eines autonomen Bergwerks werden kann. Der Hauptteil des Beitrages informiert über die grundsätzliche Projektidee, den aktuell erreichten Status, die weiter geplanten Arbeitsschritte und betrachtet die zur erwartenden Vorteile für die Schachtbetreiber. Insbesondere sollen die ganz aktuellen Erkenntnisse eines Anwenderworkshops dargestellt werden.

The increasing focus on better building insulation is important to lower energy consumption. Development of new and improved insulation materials can contribute to solving this problem. Foam glass has a good insulating effect due to its large gas volume (porosity >90 %). It can be produced with open or closed pores. If only open pores exist, air is the dominating medium for the insulating effect. However, closed pores make it possible to trap gases inside the foam. The gas can be introduced either chemically, through foaming agents, or physically, by gas compression-decompression at high temperatures. By introducing the gas physically it is possible to control composition of both the gas phase and the solid phase of the foam glass. In this work we have prepared foam glasses by physical foaming. Panel glass powder from obsolete televisions was first sintered under a gas pressure of 5-25 MPa using helium, nitrogen, or argon. The sintering result in closed-porous body with high pressure bubbles. Subsequent reheating above the glass transition temperature resulted in an expansion of the bubbles. The entrapped gas composition was analysed by gas chromatography. Furthermore, we investigated how the thermal conductivity varies with gas composition. This allows us to determine the contribution of the gas and solid phase to the total thermal conductivity of a foam glass.

Foam glass is a high added value product which contributes to waste recycling and energy efficiency through heat insulation. The foaming can be initiated by a chemical or physical process. Chemical foaming with aid of a foaming agent is the dominant industrial process. Physical foaming has two variations. One way is by saturation of glass melts with gas. The other involves sintering of powdered glass under a high gas pressure resulting in glass pellets with high pressure bubbles entrapped. Reheating the glass pellets above the glass transition temperature under ambient pressure allows the bubbles to expand. After heat-treatment foam glass can be obtained with porosities of 80–90 %. In this study we conduct physical foaming of cathode ray tube (CRT) panel glass by sintering under high pressure (5-25 MPa) using helium, nitrogen, or argon at 640 °C (~108 Pa s). Reheating a sample in a heating microscope above maximum foaming temperature gives a suitable foaming temperature for the remaining samples. We show that the foaming kinetics depend on the type of gas and the pressure. A critical pressure of around 20 MPa is found to give the largest expansion for all gasses. Samples are obtained with 100 % closed porosity for argon and nitrogen samples (5-20 MPa) and for helium samples (5-15 MPa). The pore structure of the samples is analysed to understand the critical pressure.

The foam glass production allows low cost recycling of postconsumer glass and industrial waste materials as foaming agent or as melt resource. Foam glass is commonly produced by utilising milled glass mixed with a foaming agent. The powder mixture is heat-treated to around 10^3.7 – 10^6 Pa s, which result in viscous sintering and subsequent foaming of the glass melt. The porous glass melt is cooled down to room temperature to freeze-in the foam structure. The resulting foam glass is applied in constructions as a light weight material to reduce load bearing capacity and as heat insulating material in buildings and industry. We foam panel glass from old televisions with different foaming agents. We discuss the foaming ability and the foaming mechanism of different foaming systems. We compare several studies to define a viscous window for preparing low density foam glass. However, preparing foam glass within the viscous window does not guarantee foam glass with closed pores. Instead, a single measurement with heating microscope can give us a more precise temperature range for preparing foam glass with both closed pores and low density. The foam glass production allows low cost recycling of postconsumer glass and industrial waste materials as foaming agent or as melt resource. Foam glass is commonly produced by utilising milled glass mixed with a foaming agent. The powder mixture is heat-treated to around 10^3.7 – 10^6 Pa s, which result in viscous sintering and subsequent foaming of the glass melt. The porous glass melt is cooled down to room temperature to freeze-in the foam structure. The resulting foam glass is applied in constructions as a light weight material to reduce load bearing capacity and as heat insulating material in buildings and industry. We foam panel glass from old televisions with different foaming agents. We discuss the foaming ability and the foaming mechanism of different foaming systems. We compare several studies to define a viscous window for preparing low density foam glass. However, preparing foam glass within the viscous window does not guarantee foam glass with closed pores. Instead, a single measurement with heating microscope can give us a more precise temperature range for preparing foam glass with both closed pores and low density.

The present invention relates to a production process of foam glass from a mixture of glass cullet or slag or fly ash with a foaming agent and an oxidizing agent and heating to below 1100 C under low oxygen atmosphere. The invention relates more particularly to a process wherein pure carbon or a compound which yields pure carbon as the foaming agent is oxidized by a sufficient amount of an efficient oxidizing agent essentially added to the glass-carbon powder mixture, where the oxidizing agent supplies oxygen in the relevant temperature range, to release CO/CO2 gas mixture in the softened glass at elevated temperature, to form a foamed material with CO2 gas filled cells.