Physicochemical Analysis of Distribution of Useful Components in Waste in the Thermal Energy Sector
- PDF / 399,968 Bytes
- 13 Pages / 612 x 792 pts (letter) Page_size
- 93 Downloads / 168 Views
______________________________ _______________________________________________________________________________________________________________________________________
MINERAL DRESSING
_________________________________ ___________________________________________________________________________________________________________________________________
Physicochemical Analysis of Distribution of Useful Components in Waste in the Thermal Energy Sector V. S. Rimkevicha*, A. P. Sorokina, A. A. Pushkina, and I. V. Girenkoa a
Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk, 675000 Russia *e-mail: [email protected] Received March 25, 2020 Revised March 27, 2020 Accepted May 29, 2020
Abstract—The physicochemical analysis of distribution of useful components in processing of ash and slag of the thermal energy sector plants is performed. The article describes thermodynamics and kinetics of chemical reactions during agglomeration of feedstock and ammonium hydrofluoride at the temperatures of 50–200 °С, sublimation of ammonium hexafluorosilicate in the temperature range of 350–550 °С, production of amorphous silica nanoparticles, alumina particles and red iron oxide pigment, as well as formation of calcium fluoride (Ca, Y)F2 which is a concentrator of rare and other elements. The efficient technology is developed for processing of electromagnetic fraction of ash and slag with integrated recovery of various useful components. Keywords: Mining and processing waste, integrated processing, distribution of elements, efficient method, amorphous silica, alumina, useful components. DOI: 10.1134/S1062739120036751
INTRODUCTION
Coal production and export are the substantial components of Russia’s economy. Russian coal mining companies benefit from the low cost of coal due to its shallow occurrence and therefore prevalence of the open pit method of coal mining. A good part of produced coal (70%) is subjected to combustion at heat power plants. Coal consumption by thermal generating stations can grow to 150 Mt by 2030 in Russia [1]. The increment in ash and slag waste is proportional. Disposal and longterm storage of the thermal energy sector waste is complicated due to extremely inefficient processing which only covers 10% of total mass. Coal burnt at heat power plants contains many useful components, including rare elements and noble metals. Their content in post-combustion ash and slag grows by 5–6 times and may appeal industry [2, 3]. Coal ash is rich with oxides of aluminum (15–25%), iron (6–15%) and silicon (40–60%), and contains micro admixes of nearly 50 elements from periodic tables. Regarding complex and multi-component material constitution, the heat power plant waste is similar to manmade deposits of metals and nonmetals, occurs on the surface, needs no money to be extracted from underground and features permanent growth in amount. Ash recycling is a common business. More than 300 known technologies of ash processing and re-use mostly aim at the building industry and produ
Data Loading...
