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Date submitted2023-06-21
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Date accepted2023-10-25
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Date published2024-08-26
Specific action of collector from phosphoric acid alkyl esters class in flotation of apatite-nepheline ores
Increasing amount of apatite-nepheline ores with complex mineral composition involved in processing, growing content of the associated minerals in ore which are similar in their floatability to apatite lead to the necessity of using highly selective collectors. Non-frothing flotation method gave a comparative assessment of floatability of pure minerals and demonstrated a high selectivity of the action of phosphoric acid esters in relation to apatite. The effect of four reagent modes differing in the number of selective synthetic collectors was studied using the example of flotation of an apatite-nepheline ore sample containing 17.27 % apatite and 40.18 % nepheline. Mineralogical analysis of crushed ore showed that it contained two apatite varieties – coarse-grained free and finer poikilitic as inclusions in rock-forming minerals. Free apatite opens and occurs as open grains even in coarse-grained (+0.16 mm) grades. Poikilitic apatite occurs as intergrowths with different minerals, mainly with nepheline and its alteration products (natrolite, spreustein, sodalite, etc.), and pyroxene. Optical microscopy demonstrated that a growing share of reagent from the phosphoric acid oxyethylated esters class in the composition of the collector mixture allows improving the quality of the produced apatite concentrates by reducing the number of apatite intergrowths with nepheline and pyroxenes in the concentrates. In the concentrate obtained in the most selective reagent mode, the intergrowths are characterized by a 50/50 and higher ratio in favour of apatite. Concentrates of lower quality comprised intergrowths with lower apatite content, to 20/80 or less.
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Date submitted2022-01-16
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Date accepted2022-04-06
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Date published2023-04-25
Production of biodiesel fuel from vegetable raw materials
One way to reduce the amount of harmful emissions from diesel fuel could be the replacement of part of the fuel with biofuel. Research is related to the production of biodiesel fuel in three ways: transesterification of vegetable oils; esterification of fat acids extracted from vegetable oil; and hydroprocessing of vegetable oils using catalysts in the diesel hydrotreatment process. Food and non-food oils, monatomic and diatomic alcohols were used to produce biodiesel fuel. Optimal parameters of vegetable oil transesterification have been determined: temperature; raw material ratio (oil/alcohol); mixing speed; time; type of process catalyst. The characteristics of the obtained biodiesel fuel samples were studied and compared with each other as well as with the requirements of EN 14214 “Automotive fuels. Fat acid methyl ethers for diesel engines. General technical requirements” and EN 590:2009 “EURO diesel fuel. Technical specifications”. With regard to the physical and chemical characteristics of biodiesel fuel, the best way to produce it is by transesterification of vegetable oils. However, all fuels can be used as components of a blended environmentally friendly diesel fuel.
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Date submitted2018-01-15
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Date accepted2018-02-28
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Date published2018-06-22
About the role of hydrafed calcium carboaluminates in improving the technology of complex processing of nephelines
- Authors:
- V. M. Sizyakov
- V. N. Brichkin
The scientific justification and development of the method for industrial synthesis of complex aluminates of alkaline earth metals is an innovative solution that determined several directions in the development of technology for complex processing of nepheline raw materials. It ensures the production of high-quality metallurgical alumina, the effective utilization of nepheline sludge and production of new types of multipurpose by-products. The modern development of these technical solutions is associated with ensuring the energy efficiency of the synthesis of hydrafed calcium carboaluminates (HCCA) and increasing the level of purification of aluminate solutions. The conditions for synthesizing HCCA with the use of calcareous materials of natural and technogenic origin have been experimentally determined, which makes it possible to isolate the average particle diameter as one of the determining factors of this process. The effect of the turnover of the hydrogarnet sludge on the removal of kinetic limitations in the process of deep desalination of aluminous solutions is theoretically justified. The conditions of a two-stage dosage of HCCA are experimentally determined. It is shown that the optimum ratio of the amount of the reagent supplied in the first and second stages is about 3: 2. At the same time, the maximum degree of precipitation of silica provides the production of aluminate solutions with a silicon module at the level of 95,000, which is achieved by using a HCCA synthesized based on chemically precipitated calcium carbonate in the processing of wastes from the production of mineral fertilizers.
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Date submitted2013-07-17
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Date accepted2013-09-07
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Date published2014-03-17
Increasing efficiency and mine resource development on the Prokopevsk-Kisilevsky deposit
The security issues of the deep mining of Prokopevsk-Kisilevsky deposit the Kuzbass are considered. The analysis of the existing technologies and systems development are executed. The recommendations to improvement of the technical and economic parameters, reducing accidents and injuries of the working off inventories powerful coal steeply inclined seams and steep coal seams were given.
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Date submitted2009-10-23
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Date accepted2009-12-11
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Date published2010-09-22
Aspects in geomechanics and safety in exploration of solid mineral deposits
- Authors:
- A. I. Perepelitsyn
The paper deals with the aspects of safety in mining at the ore mine «Norilsk nickel», the Yakovlevsky iron ore deposit, the Verkhnekamsk potassium-magnesium deposit of salts. It was shown that with due account of state of mining at the objects related to the utilization of the Earth's interior, the normative-legal support of mining regulation in the field of geomechanics is rather actual and it requires researches into the activities of mining enterprises as well as in the control work carried out by supervisory bodies of Mining Supervision.
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Date submitted2009-10-12
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Date accepted2009-12-19
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Date published2010-09-22
Preventive measures of gas-dynamic phenomena in the workings drivage on the rockburst- outburst-hazardous seams under extremely complicated geological and mining conditions
- Authors:
- V. P. Kostromin
A complex of measures preventing the manifestation of rockbursts and sudden outbursts of coal and gas has been developed. Criteria of forecasting, an assessment of efficiency of the preventive measures are suggested, as well as the necessary technical facilities and technologies.