Prospects of generation of high technologies of recycling of ash-and-slag waste of thermal power stations
The aim of our investigation was definition of the high technology directions of processing and recycling of ash waste and slags of thermal power stations. As a result of research compoundings of preparation are developed and experimental samples of ceramics (including porous ceramics), protectively-decorative coverings, glazes, enamels and engobes, porous ceramics, refractories, facing tiles are received.
Prospects of ash, slag and solid mineral industrial waste utilization
The availability in Russia and especially in the Siberian region of a great number of heat power plants working on hard coal and industrial enterprises producing a lot of mineral waste as a result of their operation raises the question of an urgent need to reduce pollution of the environment. This problem may only become more acute in future and environmental pollution will reach a level when expenditures on environmental protection will be economically efficient. It can be easily seen that the efficiency of measures taken to improve the situation in industry in terms of making production more environmentally friendly is relatively low. As a result amounts of solid mineral waste in industrial areas are steadily growing and this poses a vital difficult-to-solve problem of their recycling. At the same time it is known that solid mineral waste products contain mixtures of potentially useful mineral substances and their separation may serve as a source of practically valuable semi-processed products used in various fields of industry. Therefore it is essential to search for promising economically efficient ways of waste recycling into practically useful high-tech materials for radio, electronic, electrical, building, and other industries.
Controlled nucleation and crystallization in Fe2O3–CaO–SiO2 glass
For the first time controlled nucleation and crystallization were studied for 40Fe2O3–20CaO–40SiO2 (wt%) glass which is useful as thermoseeds for hyperthermia of cancer. To investigate the crystallization mechanism of Fe2O3–CaO–SiO2 glass, the Avrami parameter and the activation energy for crystallization were measured by isothermal and non-isothermal processes using classical and differential thermal analysis techniques. Magnetite was the main crystal phase and the maximum nucleation and crystal growth temperatures were 700 and 1000°C, respectively. The value of kinetic parameters such as the Avrami constant, the activation energy, and the frequency factor, determined using isothermal and non-isothermal processes showed excellent agreement. The slopes of the Kissinger, and Matusita and Sakka plots were almost parallel to each other, and, consequently, crystal growth is believed to occur on a fixed number of nuclei, the m values being considered to be the same as the n values. Using m=1.5 and n=1.5, it was found that diffusion-controlled crystal growth with a constant number of nuclei occurred and these result are in excellent agreement with those determined by the classical technique.