SU442356A1 - The method of regulating the firing process in a rotary kiln - Google Patents

Description

one

The invention relates to the burning of materials in rotating PVC, the qualitative flow of the technological process in which is determined by the presence of the material lining from the lining, for example, in kiln furnaces.

There is a known method for regulating the burning process in a rotary kiln, for example for producing expanded clay, which includes measuring the magnitude of the change in the current of the kiln's electric drive and supplying a control signal to the regulator of the fuel supply depending on the measured value.

The known method does not ensure the production of high quality products, and in some cases can lead to a marriage;

The purpose of the invention is to enhance; quality of the finished product

The goal is achieved by the fact that before the control signal is sent to the regulator 1

The fuel supply from the measured magnitude of the current changes in the electric drive of the furnace is used to isolate the frequency band of periodic oscillations, measure the AND} amplitude, and compare it with the set value corresponding to the optimum quality of the finished product.

FIG. Shows the distribution pattern of the material in the furnace during a fire; Fig. 2 shows the nature of the distribution of the material at the optimum degree of calcination; Fig. 3 shows the nature of the distribution of material in the furnace during burn-through; Fig. 4 shows the amplitude-frequency characteristic of the current oscillations of the electric drive of the furnace, which characterizes the degree of firing of the material in Fig. 5, a device designed to implement a method for regulating the burning process in a rotary kiln.

The device includes flow I, electric drive 2, fuel injector 3, regulator 4. fuel supply {sensor}, sensor 5 of the current electromotive water 2, block b for extracting and converting the amplitude-frequency signal, correction regulator 7, setpoint 8 of reference signals, automatic setting device 9, fuel consumption regulator 10, (A is the point on the upstream branch of the amplitude-frequency characteristic corresponding to the magnitude of the reference signal A of the extremesh, to the point of the amplitude-frequency frequency / characteristics; 1; Periodic; no change in the current of the electric drive of the furnace are directly related to the firing process. Initial: the moment in the absence of the material lining from the lining, there is no periodic change in the current value, since the angle of repose remains constant and only the overflow of granules is observed. Periodic lifting of the material to the lining and its complete separation from It is a necessary recognition of the normal firing mode. With a further increase in the thermal potential, the frequency and amplitude of oscillations will increase and reach a maximum at. optimum firing degree. (maximum dumping When the frequencies are burned out, the amplitude of the oscillations I n is reduced due to the later and incomplete separation of the excess material from the lining and during circular setting (Fig. 3) again becomes equal to zero. Thus, there is an extreme degree of amplitude The frequency characteristic of the current oscillations of the furnace electric wire depending on the degree of firing of the material.) The control of the firing process is carried out as follows. From a sensor 5, for example, a current transformer, a signal proportional to the current of the electric drive is supplied to a selection and conversion unit of an amplitude-frequency signal 5, which allocates an oscillation frequency band, for example, a band-type filter mc, converts the amplitude of the selected band frequencies in the control signal, for example, the PR-I attachment, this signal is compared in the measuring unit by adjusting the adjusting 6p 7, for example, type P1SH, with the reference setpoint signal of the setting device 8. Thus, in the correction regulator you compare with a predetermined value of the controlled parameter (blade material of the furnace lining) is measured continuously with emym kuschim its tag value equals blade If these signals to the output signal of the regulator is zero. When the characteristics of the calcined raw materials change, the tone of the fuel or the calcination mode and the displacement of the current value of the amplitude-frequency characteristic In from the predetermined value caused by ETS.1, the correction regulator 7 produces. control impulse of the corresponding sign (more, less), which is fed to the input of the automatic. The control unit 9 (for example, VMA), which changes the setting of the fuel consumption controller 10, the Retourer 10, through the regulator 4, influences the fuel consumption, sets such a firing mode in which the value of the w-shlit-frequency-frequency characteristic of the electrical switch -; the drive becomes equal to the specified value. The pulse value is selected as the specified reference signal, which is proportional to the amplitude-frequency characteristic value: i point A in FIG. 4, which is close to extreme point A and the distance from it is greater than the rising branch. inertia of the firing process. This eliminates the transition of the firing process to the burnout area and excessive fuel consumption. The subject of the invention is a method for regulating the firing process in a rotary kiln, for example, for producing kerchlzite, including measuring the change in current of the electric drive of the furnace and supplying a control signal to the regulating fuel supply organ, depending on the measured value, which is similar to before the control signal is applied to the regulator of the fuel supply, the frequencies of periodic oscillations / from ep dissolved and their amplitude are compared with predetermined corresponding optimal product quality gdtrvogo

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