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Introduction

For a heat supply of a complex surface and heating of mine shafts of Ukraine are used their own boiler rooms most of them works on solid fuel. It is caused by sufficient reserves of energetic coal, but some part of coal of inferior quality, with ash content 50%, in total solid fuel in the country approach to 39% and in the sequel it will increase because of mine workings of thin layers [2]. When burning ash content coal performance factor of coal boilers fall down and their heat supply don’t reach calculating aim, consequently falls down reliability of user heat supply.

One of the most efficient combustion technologies of low-grade and high-ash (80%) coal is use of low-temperature boiling layers (STAM). This method of burning fuel is notable for high level mixing of fuel and oxidant that is higher in contrast to layer heating, and time of fuel arrival to burning area, and intensive heat sink to surface heat, absence of moving parts furnace dimension, possibility of burning fuel of different structure and quality in one aggregate, lower to 1–5% fuel content in the layer. STAM technology simplify fuel ignition, prevent fuel particle caking and slagging of the convective heating surfaces [4].

The actuality of the topic

In connection with the increasing share of coal of an inferior quality, with ash content up to 50% connected with an increase in the number of thin layers in the country is topical application of boiler installations with low-temperature boiling layer that can use given type of fuel.

Currently, management of boiler unit with low-temperature boiling layer is carried out by operator manually and it is not always successful and as result it is accompany with forced standing idles of equipment but in worse case with suspension of technological process.

Given boiler installations are used in Ukraine for a long time. Over the whole period wasn’t made the development of automation objects. A modernization of the boiler-house automation equipment installation is necessary.

The characteristic of object’s automation

Burning in a boiling layer – one of technologies of burning of solid fuels in power coppers at which in a fire chamber the boiling layer from particles of fuel and nonflammable materials is created. The technology was introduced in power from the chemical industry approximately in the 1970th [9].

Technologies of burning of fuels

In a gas upward flow loading from solid particles can be in three conditions:

The boiling layer can be high-temperature and low-temperature (800–900 °C), now for some reasons are almost always used by the second. In particular, in this allocation of oxides of nitrogen very effectively chokes and it is possible to apply a immersion of the surface, which the factor of heat kickback to (warm particles of fuel is exclusively high adjoin to it directly, and the part of heat is transferred not by convection, and heat conductivity). For resetting of temperature of a layer in order to avoid a slagging it is possible to enter water and steam, but in principle because of high abrasivity of this layer of a fire chamber with its application to slagging aren't inclined.

In the fluidized bed are significant number of inert fillers-slag, sand, dolomite, limestone; they enhance convective heat. Dolomite and limestone, in addition, share in up to 90% of the carbon dioxide of sulphur oxides. Fuel may be coal (including in the form of a residue in ash from low-efficiency boilers), oil shale, peat, wood and other waste.

Fluidized bed furnaces are not as sensitive to fuel quality in terms of its chemical composition, but are sensitive to the homogeneity of fractionary fuel and an inert particle charging [3]. Burning in given furnaces is more intensive than in traditional layers, they are smaller ; However, they require a air discharge array and the more powerful fan .Other disadvantages of this type:

Effect of intensive burning, similar to the observed combustion fluidized bed, you can get a permanent shake of fire bar with chunks of fuel of any size; but due to the weakening of the metal of fire bar at high temperatures, this is difficult to implement.

Fluidized bed furnaces pressurized up to 16 kgf/sm² with deep cleaning of gas from the ash can be used for the organization of work of the gas turbines on the solid fuel (in the high-pressure steam generator PGU)

Conclusion

Rising energy prices, the lack of own fuel resources, the decline of the coal quality, increased requirements to reduce environmental pollution, require introduction in the production more modern method of burning coal.

It is the availability of fuel and energy resources determine the pace and scope of individual areas of industrial and agricultural production. The main aims are to achieve more complex processing of raw materials, creation of resource-saving techniques and technologies that dramatically reduce losses and waste. In recent years in many countries the restructuring of the fuel mix to reduce dependence on oil and gas has revived interest in the coal field.


Note

When writing this abstract the master’s qualification work is not completed. Final date of completion: December 15, 2012. Full text of the work and materials on the topic of work can be obtained from the author or his supervisor after the specified date.

References

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