The Abstract:

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A sharp energetical and ecological situation in Ukraine, and particulary in Donbass, needs effective actions, aimed to rasing fuel and energy balance of the country, and, naturally, solving problems related to the environment. It is known, many fine particles having the size 0-0.5mm , appear in the process of output, transportation and preparation of coal. In a number of cases their size in general mass of prepared material runs up to 30 – 40 %. As a rule, the content of concentrate in coal of such largeness is great, that is related to less durability of combustible mass in comparing with bed.

Flotation is used for preparation of coals with the size 0 - 0.5 mm. It is practically the only process of preparation of wastes on preparation factories. Solution of problem increasing the mass of preparation expanssion of concentrate production for coking and energetics and increasing of his quality is closely connected with flotation efficiency increasing.

Due to not 100% efficiency of traditional foamy flotation coal particles get into down layer and are taken away to sludge tanks. Ash of this product variates from 55 to 65 %. This leads to loosing of thousands of tons of combustible mass which should be used.

Besides sludge tanks occupy sizeable areas (about 1.5 million m2), drainage through sludge tanks bottom leads to pollution of aquifers and there is an evaporation to the atmosphere from the sludge tank surface. All of this results in worsening of ecological situation in the industrial regions of country and is the evidence of necessity of selectivity increase and efficiency of coal fine particles preparation.

The purpose of this work is research and development of methods of utilization of sludge tank products. Sludge tank of CPF “Sholokhovskya” is takens as an example.

Tasks of work:

-the research of physic-chemical properties of solid sludge tand phase and working out the plan of sludge tank;

-development and calculation of technological sheme of wastes processing;

-consideration of methods of low ash processing;

-research of methods of hight ash wastes preparation by granulation in a boiling layer;

-economic analysis.

1. Complex solution of ful utilization of sludge tanks is offered.

2. The mathematical models of process of spiral separation process of wastes are got. They allow to define the rational models of process and forecast the results of preparation.

Because of relatively low ash of wastes, essentially, some sludge tanks are deposits from which it is technically possible to get a power fuel, and occasionally a concentrate for coking.

The quality indexes of wastes, that are kept in sludge tanks, hesitate in wide limits in depth and distributing area, that make it difficalt to process. In addition, each sludge tank depending on the coal faction grade and characteristic requires individual approach during development of technology of its use.

Complex utilization of wastes acquires significance of not only important reserve of efficiency of production increasing, reducing inefficient alienation of the land resources but also to protecting from of water and air pollution.

It should be noted that such machines as hydrosayzers and spiral separators produced in our country and abroud can be used for processing the part of superfine material. They successfully compete with the flotation in preparation particles larger 0.2 mm. Their part in wastes often ezceeds 30 %.

Thus, there is a necessity in deposits processing, that will allow not only toget the additional amount of fuel and raw material for energy but also solve ecological problems of Donbass.

So, the development of the most rational technology of processing of superfine materials of sludge tanks and determination of economical appropriate p plants construction with the use of modern equipment is a very actual task.

Depending on sludge tanks content characteristicsthe following variants of its working off are possible:

1. Excavation and depending on its ash to make shipping to thermo-powerstations after the air drying (Аd <45 %) or to the nearest preparation factory for repreparation (at Аd 45 - 60 %).

2. Building of technological complex with the wastes coulisse by a hydraulic dredger and its preparation at the simple gravitation plants (at Аd 45 - 60 %).

3. Repreparation of wastes at improved preparation factories for low ash sludge tanks (Аd<55 %), containing coking grades of coal.

4. To prepare hight ash wastes of sludge tanks (Аd>60-65 %) to burning in heating engineering objects, equipped heatings with a boiling layer.

Accepting the rational variant of sludge tank working off ilonakopitelya will demand information about wastes characteristics (passport, cadastre) and deep economic analysis.

It is worth to take into account:

1. Repreparation of flotation wastes with ash more than 65 % in any way is unprofitably at the present time;

2. Repreparation of flotation wastes at an operating factory will demand prior researches and improvement of its technology;

3. In processing para 2 - it is necessary to foresee preparation of the mois wastes that are again to stockpiling in dumps;

4. It is technically possible to single out concentrate with ash to 10% on its vent to 30 % during repreparation of coked wastes with ash 45-50% (para 3).

Utilization of raw material and re-use of stockpiled products of sludge tanks solves the problem of power mediums lack, and also liquidates sludge tanks, usage of which results in alienation of sizeable areas of earth, pollution of water and atmosphere pool and worsening of ecological situation of industrial regions of country.

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