Utilization of Acoustic Field Energy for Reduction of Dust Discharge in High-Temperature Furnaces

In order to reduce the total dust discharge from high-temperature furnaces, this study advocates the use of the energy of the acoustic field formed in the furnace body with application of acoustic generators of Hartmann whistle type. The paper provides theoretical justification of dust precipitation inside the furnace and develops principles of its implementation. The efficiency of this method is shown by examples of industrial implementation. Keywords: dust precipitation inside the furnace, acoustic field energy, Hartmann whistle

Intense Pulse Light Annealing for Perovskite Photovoltaics

Rapid advancements within photovoltaics realm necessitates swift fabrication of the modules using cheap materials through cost effective manufacturing processes to achieve short cost payback time. Photovoltaics manufacturing includes chemical processing of the materials followed by thermal annealing. Yet, long-term annealing of the materials using high temperature furnaces have remained the prevalent post-processing approach in industry which necessitates alternative methods to achieve high performance modules through rapid and economical processes. Intense pulse light (IPL) has been successfully applied as a promising rapid post-process annealing for various thin film photovoltaics, particularly to process the organic-inorganic perovskite solar cell (PSC) layers. In this paper, several results pertinent to the application of IPL on perovskite and SnO2 electron transport thin films are presented and the role of IPL on rapid thermal annealing (RTA) is explained. We show that swift fabrication of PSCs through IPL can result in efficiencies exceeding 16% when the Perovskite film is annealed with aid of CH2I2 alkyl halide additive in the ambient with 60% relative humidity. In addition, the synergy of IPL-alkyl halide interaction for other perovskite chemistries is introduced. We show that achieving to PSCs exceeding 12% efficiency was possible when the perovskite and SnO2 ETL was annealed sequentially through IPL.

Electrochemical Recycling of Platinum Group Metals from Spent Catalytic Converters

Platinum group metals (PGMs: Pt, Pd, and Rh) are used extensively by the industry, while the natural resources are limited. The PGM concentration in spent catalytic converters is 100 times larger than in natural occurring ores. Traditional PGM methods use high temperature furnaces and strong oxidants, thus polluting the environment. Electrochemical studies showed that platinum can be converted to their chloride form. The amount of dissolved PGM was monitored by inductively coupled plasma-optical emission spectroscopy and the structure was identified by ultraviolet-visible spectroscopy. An electrochemistry protocol was designed to maximize platinum dissolution, which was then used for a spent catalytic converter. A key finding is the use of potential step that enhances the dissolution rate by a factor of 4. Recycling rates as high as 50% were achieved in 24 h without any pretreatment of the catalyst. The method developed herein is part of a current need to make the PGM recycling process more sustainable.

Directions of development of production of small- size billets for long products

The aim of the work is to study the technological features of the transfer of metallurgical enterprises to the production of small-size and wire metal products from continuously cast billets. The main parameters of the rolling technology are considered: the size of the billet, the choice of the location of the continuous casting machine, the transfer scheme of continuously cast billets to small- size and wire mills. It is shown that when using a continuously cast square billet with a size of 130x130 mm and 150x150 mm, direct combination of a continuous casting machine with a rolling mill is almost impossible due to the difference in the speed of continuous casting and the roughing group of the mill. The performed calculations show that the scheme of cutting the billets and combining with the intermediate furnace is technologically feasible, however, further heating of the billets leads to significant energy losses. It has been established that an effective option for combining the continuous casting machine with a rolling mill is to use a complex of equipment with a furnace-thermostat for a billets 120 m long. This flowchart reduces the energy consumption for heating the billets by at least 53%. The proposed technology of combining the continuous casting machine with a rolling mill will provide metal savings by reducing the thickness of the scale to 0.4-0.73 mm (an average of 1.1% of the mass of the billet), improve its quality by reducing the depth of the decarburized layer from 1.1 mm to 0.3 mm. The technology provides for the transportation of liquid steel in the ladle from the steel-smelting shop, casting on the continuous casting machine, identification of defects in the billets in a hot condition, supply of the billets with a temperature of 8500С to high-temperature furnaces for heating and subsequent rolling.

Adhesive Bonding of Oxide Ceramics for Complex Ceramic Parts in High Temperature Furnaces

Within the scope of the project ENERTHERM: Energy efficiency of thermal processes which is funded by the Bavarian Ministry of Economy (BMWi) components and systems for high-temperature are being developed. Monolithic oxide ceramics (mullite, Al2O3) and oxide-fiber reinforced ceramics (O-CMC) show a high potential for high temperature (HT) applications. Additionally, the demand for complex HT-components such as HT-fanwheels for kilns, supporting HT-lightweight structures or hot gas liners increases. In according to the required component design, joining techniques are needed in order to realize such complex geometries. The generated joints were made by using commercial glass solder from the type Al2O3-SiO2-MgO. For realizing the joining process sintering-joining in HT-kilns was used because of the homogeneous temperature distribution. A CO2 laser (wavelength of 10.6 microns and a power of 1.5 kW) was used for rapid joining process. The mechanical properties were determined in according to DIN EN 843-1 and DIN EN 658-3 (4-point bending strength) and evaluated according to Weibull distribution.