One of the most actual problem of power engineering
nowadays is the problem of rational use of energetic resources of our planet.
It includes search of alternative heat-carrying agents and also the development
of new more effective methods of exploitation of existing ones. The solution of
this problem is very important because of critical situation in fuel &
energetic industry of Ukraine. The cause of such unfavorable conditions is the
deficit of all kinds of fuel, great decrease of the coal production volume and
essential deterioration of the quality of extract coal for the last 20 years
(ash content of coal run up to 35%).
The solution of this problem is necessary to look for
in involving into industry exploitation new power resources, which have not
been accounted in fuel and energy balance of the country until now and also the
development oh the methods of exploitation fuel resources letting absolutely
use of their heat potential and make the loss of energy minimum. One of the way
to solve this problem is the installation of the new burning solid fuel
technologies by different derivatives of fluidized bed. One of the first place
takes the burning solid fuel technology of the low-temperature fluidized bed.
Thanks to installation of this technology it becomes
possible to use the supply of low-quality solid fuel, utilization of the wastes
of coal mining and separation. It is possible to burn coal of 70% ash content
in this way. And the average mechanical waste of coal makes up only 2-3 % under
40% of burning coal in usual grate-fired furnace.
The special feature of this technology is that coal is
in air-fluidized bed condition during burning process. It is achieved by
blowing air into the funace with the speed which provides suspended condition
of the coal particles. It facilitates the oxygen admission to them and makes
the burning process more effective. The bed temperature must be between 750 and
850 0C to avoid coal slagging and clinkering. We can use raking off the slag
because the ash particles settle-down. The solid fuel feed process is
continuous and fuel consumption depends on the bed temperature value. Head
emission is achieved by embedded heat surface.
To provide optimum quality index of burning process it
is necessary to achieve high quality of the controlled process. The absolutely
control of solid fuel burning process proceeding becomes possible with the use
of automatic control system of low-temperature fluidized bed. It makes possible
to provide necessary heat quality indexes, support technological quality
indexes on optimal level and as a result increase the capacity and effeciency
and realize emergency control. We can achieve necessary control quality only
with the way of complex technological parameters state control in the
low-temperature fluidized bed furnace. Following this individual parameter
control (e. g. temperature control) must be realized only with the account of
the values of all another parameters and on the base of their state analysis
make the decision about further burning process control. We offer automatic
temperature and fuel consumption control system for low-temperature fluidized
bed. It makes possible to hold the main technological parameter –temperature on
the order level with the way of solid fuel consumption regulation depends of
the temperature value.
It allows to hold the high heat emission level,
prevent damade working conditions connected with coal slogging and clinkering,
provide optimal fuel consumption. It considerably decreases coal losses and
increases the coal use economical effect.
So we can see that
the use of the new coal air-fluidized bed technologies with automatic control
system development allow to solve the problem of heating resources deficit. And
the industry installation of the air-fluidized bed furnace makes the great
economical effect (the year summary economy of the 30 air-fluidized bed
furnaces is more then 5 million grn).
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