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Date submitted2024-04-22
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Date accepted2024-06-13
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Date published2024-07-04
Lithification of leachate from municipal solid waste landfills with blast furnace slag
- Authors:
- Mariya A. Pashkevich
- Yuliya A. Kulikova
The article presents an alternative method of utilization of blast furnace slag and leachate from solid municipal waste landfills, the formation of which occurs during the infiltration of atmospheric precipitation through the thickness of deposited waste. The method is based on the conversion of leachate from the liquid phase to the solid aggregate state by lithification using blast furnace slag as an astringent material. The hydraulic activity of slag, which depends on the amount of oxides contained in it, has been estimated. The investigated slag belongs to the 3rd grade, which confirms the possibility of its use as an astringent material. The filtrate was analyzed for the content of various elements, and the maximum permissible concentrations for each element were found to be exceeded. Chemical and biological oxygen demand were determined, and critically high values were installed (17200 mgO2/l and 4750 mgO2/l, respectively). The lithification process was divided into two stages. The first stage was to reduce the organic component in the filtrate using a coagulant, aluminum sulfate; the second stage was slag hydration. The optimum ratio of lithificate components in terms of mixture solidification rate was established at 1:0.03:1.25 (leachate, coagulant, blast furnace slag). The obtained material was analyzed for the solubility and content of various forms of metal. It is established that at infiltration of atmospheric precipitations through lithificate only 3 % of material will be washed out; concentrations of gross and mobile forms of heavy metals do not exceed the maximum permissible, except for the gross content of arsenic, mobile, and water-soluble forms of which were not found. The values of chemical (687 mgO2/l) and biological (173 mgO2/l) oxygen demand in the aqueous extract from lithificate decreased more than 25 times in comparison with the initial filtrate. According to the results of toxicological studies, lithificate was assigned an IV class of waste hazard, which confirms the possibility of its use as bulk material at landfills.
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Date submitted2009-10-18
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Date accepted2009-12-09
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Date published2010-09-22
Influence of blocky-hierarchy structure of geological medium on the forming of natural and technogenic geodynamic fields in the North-West part of the Amur geoblock
- Authors:
- I. Yu. Rasskazov
- B. G. Saksin
On the example of the South-Argun uranium ore district of Zabaikalie consideration is given to the interaction of regional and local fields of stresses. The district includes a number of deposits prone to rock bursts. The performed analysis contains data on recent geodynamics of the explored part of the Amur geoblock as well as on geomechanical and geologo-structural materials of Tulukuev caldera and of Antey deposit. It is shown that with the use of the M.A. Sadovsky relationship the indices of local structural forms of a row are subjected to unified laws of deformation and fracturing. Conclusion was made that at the beginning of deposit exploitation the direction of action of stress field within rock mass conformed to regional one, and then it considerably changed under influence of large-scale mining operations.
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Date submitted2009-10-10
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Date accepted2009-12-02
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Date published2010-09-22
Deformational precursors of technogenic earthquakes in mining the hydrocarbon deposits
During monitoring since 2005 to 2008 at the Astrakhan gas-field it has been recorded three technogenic earthquakes. Results of geodetic levelling for the given period allow to approve that seismic event is preceded by raisings of a surface and its subsequent subsidence as a its result of unloading. That allows to use geodetic levelling for the forecast of technogenic seismic phenomena for oil and gas fields.