Quality of coal seam D of Muara Enim Formation, Central Palembang Subbasin

Coal seam D belongs to Muara Enim Formation in Central Palembang Subbasin, South Sumatera Basin, which ages of Middle Miocene to Late Miocene. This study aims to determine the quality of the coal, especially sulphur content and form, ash content and composition, and trace elements of heavy metals. Those are important to know as a reference in suitability in the use of this coal. Methods of analysis is proximate, total of sulphur, form of sulphur, SEM-EDS, ash composition, and trace element. The coal is categorized as low rank coal or lignite with a very low total sulphur max 0.25%, dominated by the organic sulphur formed during the peatification and coalification process (syngenetic). The coal has a safe ash composition. It shows from a very low metal oxide content that causes slagging and fouling at low temperatures process. Likewise, the trace element content of the coal such as chromium (Cr), cadmium (Cd), manganese (Mn), lead (Pb), nickel (Ni) is still far below the threshold for trace element content in coal.

The study of rapeseeds ash composition in the conditions of the agroecological experiment

A comparative analysis of the seeds ash composition of the breed Rif (Brassica napus L.) rapeseeds grown in the Lipetskaya region was held. The plants were grown in the conditions of the agroecological experiment using mineral (NPK and zeolite) and organic (hen droppings) fertilizers. 6 variants of the experiment were studied – the plants are grown without fertilizers application (the control); the mineral fertilizer (N60:P60:K60) separately and together with zeolite (5 t.ha-1); the zeolite in pure form (5 t.ha-1); hen droppings (5 t.ha-1) separately and together with zeolite (5 t.ha-1). We studied the accumulation of 9 basic elements (in mass %) contained in Brassica napus. seeds ash using the method of energy-dispersive X-ray spectroscopy. The accumulation order of the elements was determined: P ≈ K > Mg ≥ Ca > Mo > S > Zn > Mn > Fe. The proportion of P fluctuated from 10.852 to 11.855 mass %; the proportion of K – from 9.933 till 12.343 mass %. The rapeseeds contained Mg, Ca, and Mo in similar concentrations within the range of 4.0 -5.8 mass %. The combined application of zeolite with organic fertilizer ensured the accumulation of the minerals in the seeds. Correlations between the elements were established. High correlation between elements K and Mo was found (r = 0.96); P and Mg (0.86); P and Fe (r = 0.94); C and Mo (r = 0.86). The positive effect of the combined organic-mineral fertilizers with poultry farms wastes usage on the mineral elements accumulation in rapeseeds was stated. It is noted that the accumulation of P, Ca, Mo, and S in rape seeds leads to a decrease in Zn.

Natural radioactivity of coal in the context of radioecological safety and rational use

Introduction. Environmental contamination with natural radioactive elements is an urgent ecological problem of the coal industry. Radiation hazard associated with natural radionuclides in coals and enclosing rock is a poorly studied problem requiring special attention. Radionuclides and their combustion products in coals, i. e. ash and slag waste and gas aerosol emissions, released into the biosphere, become the sources of pollution. Radiation monitoring is required in the course of geological prospecting, deposits development and rational use. The research aims to systematize research and analytical material on specific radioactivity of coal and their combustion products, and update the problem of radioecological safety monitoring. Methodology includes studying data on specific radioactivity of coal at various deposits, studying natural radioactivity of coal, enclosing rock and ash and slag waste, describing ash and slag waste and radon as a source of radioactive contamination, assessing potential radon hazard of mine workings, and analyzing ash composition characteristics for toxicologic estimation of ash dumps and their effect on the environment. Results. Generalized data on radionuclide concentration in coal burned at the CHP facilities, slag and fly ash are presented. Radionuclide specific concentration is much higher in ash and slag waste of coal heat power industry than in initial coal. It is caused by the radionuclide concentration in the products of coal combustion. Potential hazard of radon released from rock is revealed, and ash composition is characterised for toxicologic estimation of ash dumps. Conclusions. Uncontrolled coal combustion exacerbates the problem of radioecological safety due to radioactive aerosol emission and the formation of ash and slag waste with increased concentration of natural radionuclides. System monitoring of radioactivity level in the course of geological prospecting, mining, processing and combustion will allow reducing radionuclides entering the fuel cycle and environment.

INVESTIGATION OF SUSPENDED SOLIDS IN WATER FOR COKE EXTINCTION

The article is devoted to the results of work for the study of the composition and quantitative content of suspended solids (SS) in the wastewater of coke plants before and after biochemical purification plants (BPP), as well as in other waters involved in the process of coke extinction. The characteristic indicators have been investigated of waters before and after BPP of five coke-chemical enterprises of Ukraine, as well as the chemical composition of suspended solids in water after BPP, etc. It is shown that SS in water after BPP is represented mainly by activated sludge, which is partially oxidized to CO2 when water is supplied to hot coke. The rest activated sludge is returned with water condensate to the settling tank of the extinction tower and, thus, is not emitted into the atmosphere in the form of SS. In addition to sludge, the particles of coke, coal and products of the equipment corrosion are present in the purified water after the BPP and in the water of the extinction tower settling tank. The possibility of the presence of concrete particles is also not excluded. To establish the nature of solid particles, their elemental composition and ash composition has been determined. In particular, it was found that the ash composition of suspended solids from water after BPP quantitatively differs from the both of ash composition of coal concentrates and the composition of concrete. For example, the mass fraction of silicon dioxide in the suspended solids of water after BTH is much lower than in concrete and in ash of coal concentrates. The detected predominance of iron (III) oxide in the composition of SS ash after BPP is explained by the presence in the selected samples of products of the equipment corrosion. Based on our research, it is proposed to make changes in the normative document "Technological standards of permissible emissions of pollutants from coke ovens", namely in chapter IV "Operating conditions of coke ovens" par. 8: to exclude such a normative value as the content of suspended solids in water after BPP, which is submitted for coke extinction. Keywords: water for coke extinction, water after biochemical purification, suspended solids (SS), content, chemical composition, elemental composition, ash composition. Corresponding author A.L. Borisenko, e-mail: [email protected]