VOL 87, No. 5 (2014)

The main difficulties of accurate determination of the redox state of glass are noted. The specific effect of tin on the valence equilibrium of iron in the surface layers of float glass is shown. The technique of spectrophotometric determination of different valence forms of iron in industrial silicate glasses, which is applicable for flat and hollow products, is described. The technique is highly expressive and accessible.

The possibility and energy efficiency of using natural raw materials - high-silica sedimentary rock - as a raw material in the production of colored glass containers has been revealed. The presence of phosphorus oxide in the rock affects the viscosity and crystallization properties of the synthesized glasses. The level of physical and chemical properties of the obtained glasses corresponds to the level of the main operational properties of container glass based on traditional raw materials.

The current state of research in the field of obtaining foam glass from siliceous rocks by a one-stage scheme is considered. The main technological principles underlying the pilot production of granulated foam glass based on diatomites are formulated. The production process is described and the main properties of the 5-10 mm fraction are given in comparison with the regulatory requirements.

The features of the behavior at high-temperature bending of ceramic specimens based on mullite modified with zirconium oxide have been investigated. It has also been shown that recrystallization annealing can be recommended for this material to improve its properties.

A description of a new technology for the manufacture of ceramic products (bricks, tiles, etc.) is given, which makes it possible to reduce the duration of the production cycle due to an increase in the activity of the processes occurring during pressing and firing, which makes it possible to obtain ceramic products with increased mechanical strength (45 - 60 MPa), improved marketable type and improved quality. The substantiation of the selected processing modes is given.

The understanding of the problems of glass enterprises in the course of cold and hot repairs of glass melting furnaces is reflected. JSC "DINUR" offers assistance and joint cooperation with glass enterprises. New developments of refractory products have been proposed, including the DSU-1 glass-linas grade, the characteristics of which make it possible to increase the operating life of the furnace. The characteristics of other refractory materials that can be used in various structural units of a glass furnace (vaults, regenerators, suspended walls, an arch of a loading pocket, burner blocks) are considered in detail.

Under the action of surfactants included in the polishing compositions, due to the manifestation of the Rebinder effect, the initial crystal structure of the thinnest (tenths and hundredths of a micrometer) surface layer of the processed material (silicon) is severely destroyed and its deformation and strength properties change. The use of active additives to polishing compositions, including unconventional ones, makes it possible to reduce the thickness of the damaged layer by 1.5 - 2 times, while significantly increasing the productivity of polishing.

The paper presents the results of work on stabilizing the wall thickness of quartz tubes by external vapor-phase deposition during high-temperature hydrolysis of silicon tetrachloride. The technological parameters of the deposition of the porous layer and its sintering have been determined. Defect-free glass layers with a thickness of more than 0.2 mm were obtained with the possibility of reducing the circumferential thickness difference of pipes from 0.2 to 0.05 mm.

An original concept for the development of a three-turn scheme for regenerating the heat of flue gases in glass-making furnaces is proposed. Theoretical propositions are formulated that substantiate the correctness of specifying the basic initial data for calculating a three-turn regenerator. An example of the development of a three-turn regenerator of a glass-melting furnace with a horseshoe-shaped flame is given.

Some designs of hopper dispensing devices providing a two-speed mode for dosing bulk materials when using feeders with an unregulated single-speed drive are considered.