The Latest Research in Mongolia on the Utilization of Coal Combustion By-Products

With a geological reserve of over 170 billion tons, coal is the most abundant energy source in Mongolia with six operating thermal power stations. Moreover, in Ulaanbaatar city over 210000 families live in the Ger district and use over 800000 tons of coal as a fuel. The three thermal power plants in Ulaanbaatar burn about 5 million tons of coal, resulting in more than 500000 tons of coal combustion by-products per year. Globally, the ashes produced by thermal power plants, boilers, and single ovens pose serious environmental problems. The utilization of various types of waste is one of the factors determining the sustainability of cities. Therefore, the processing of wastes for re-use or disposal is a critical topic in waste management and materials research. According to research, the Mongolian capital city's air and soil quality has reached a disastrous level. The main reasons for air pollution in Ulaanbaatar are reported as being coal-fired stoves of the Ger residential district, thermal power stations, small and medium-sized low-pressure furnaces, and motor vehicles. Previously, coal ashes have been used to prepare advanced materials such as glass-ceramics with the hardness of 6.35 GPa, geopolymer concrete with compressive strength of over 30 MPa and zeolite A with a Cr (III) removal capacity of 35.8 mg/g. Here we discuss our latest results on the utilization of fly ash for preparation of a cement stabilized base layer for paved roads, mechanically activated fly ash for use in concrete production, and coal ash from the Ger district for preparation of an adsorbent. An addition of 20% fly ash to 5-8% cement made from a mixture of road base gave a compressive strength of ~ 4MPa, which exceeds the standard. Using coal ashes from Ger district prepared a new type of adsorbent material capable of removing various organic pollutants from tannery water was developed. This ash also showed weak leaching characteristics in water and acidic environment, which opens up an excellent opportunity to utilize.

Native Metals in Far Eastern Brown Coal (Russian Federation)

Metal-bearing brown coal and coal ash can have a practical importance as the alternate sources of metals. Brown coal of Sutarsk and Ushumunsk deposits, as well as other coal deposits of the Far East, contain rare and rare-earth, precious and ferrous metals. At a comprehensive approach they can be sequentially extracted from ashes of coals in a production string. The possibility of metal extraction heavily depends on mode of their occurrence and grain size. In coals and coal ash of the researched deposits metals are localized in various mineral phases: oxides, sulfides, carbonates, phosphates, in a native mode of occurrence and as a part of intermetallic compounds. Particles are usually fine (1-30 microns). Gold, silver, copper, bismuth, iron, titanium, tungsten, zinc, barium, alloy of rare earths (cerium - lanthanum - neodymium) are found in native mode of occurrence. The interesting fact is that mode of occurrence of metals typical both for the reduction and oxidizing conditions are observed in one sample. It is necessary to account for the processing and extraction of metals from coal ashes that the most mineral particles are small and characterized by various morphology and composition.

An artificial neural network-based prediction model for utilization of coal ash in production of fired clay bricks: A review

This study analyzed the last 20 years` data available on power plant coal ashes used in clay brick production. The statistical analysis has been carried out for a total of 302 cases based on the relevant parameters reported in the literature. The chemical composition of the clays and coal ashes, percentage incorporation and maximum particle size of ash, size of fired samples, peak firing temperature, and the corresponding soaking time were selected as inputs for modeling. The product characteristics i.e. open porosity, water absorption, and compressive strength was taken as output parameters. An artificial neural network model has been developed and showed a satisfactory fit to experimental data and predicted the observed output variables with the overall coefficient of determination (r2) of 0.972 during the training period. Besides, the reduced chi-square, mean bias error, root mean square error, and mean percentage error were utilized to check the correctness of the obtained model, which proved the network generalization capability. The sensitivity analysis of the model suggested that the quantity of Na2O coming from brick clays, the percentages of SiO2 and K2O coming from ashes, and MgO coming from clays were the most influential parameters in descending order for the ash-clay composite bricks` quality, mostly owing to the influence of fluxes during firing.

“Organic food” – makes pharmaceutical industries work against insects – a danger for society in general

The author’s works have shown in various ways the absence of dangerosity of pesticides for human health, as all the studies claiming to find effects forget the side contamination with alpha-emitting nanoparticulates (from radon, phosphated fertilizers, car fumes, coal ashes for instance) that interacts with the samples and destroys the scientific validity of the results. This paper looks at the issue of organic food in a different way, because organic food also thrives on the sheer claim that it benefits to insects, and the author’s results here show that this is not the case too.

“Spitting as traditional medicine” – why alpha-emitting nanoparticulates make spitting an unfortunate but significant contribution to health

Spitting is a human reflex as old as civilization, related, mainly, as is shown, to the evacuation of internal contamination with alpha-emitting nanoparticulates, a contamination with many causes, from car fumes and industrial smokes, coal ashes and cement, radon, phosphated fertilizers, to depleted uranium weapons and natural dust and tap water in areas of high natural radioactivity, as well as cigarettes, for the main sources. Strong levels of coal ash pollution together with high natural radioactivity explain for instance the spitting “custom” in Chinese streets, together with long distances between workplace and home, widespread cigarette use, and lack of public toilets. Alphaemitting nanoparticulates become a part of the digestion cycle in meat-eaters, but not without collateral damage.