SU1170228A1 - Device for controlling capacity of boiler set pulverized-coal feeders - Google Patents

Abstract

1. A DEVICE FOR ADJUSTING THE PRODUCTIVITY OF THE BOILER HEATER TYPES, attached to a common brewer of a pack, containing a control unit of a dust picker with a regulator, connected inputs with a setting unit and a sensor of the aerosy mixture, which is attached to a device using a device and a device that is attached to a device using a device that is attached to a device using a device that is attached to a device using a device that is attached to a device that is attached to a device that is attached to a device that is attached to a device and that is attached to a device that is attached to a device. In order to increase the control accuracy, the air mixture temperature sensor is installed beyond the entry area at a distance of 5-8 diameters of the dust pipe. 2. A device according to claim 1, characterized in that, in order to increase the speed, the sensor 9 of the temperature of the aerosymbi is made in the form of a thermocouple with a bare hot junction.

Description

The invention relates to the control of boilers in which coal dust is transported to the burners by air at a concentration of not more than 0.5-1.0 kg per cubic meter (conventional pneumatic transport), each dust feeder being equipped with a separate actuating mechanism for changing the capacity. It is known a device for controlling the performance of balers of a boiler unit, containing a regulator of a bourgeoiser with a regulator connected to the inputs with a control unit and an air mixture temperature sensor installed in the dust pipe beyond the input of coal dust 1, However, the known device does not provide reliable and accurate control: because The temperature sensor of the aerosol mixture is installed in a ppt.provod, it either wears out quickly or has great inactivity. The purpose of the invention is to increase full adjustment and speeding up. The goal is achieved by the fact that in the device for controlling the performance of the boiler unit's dust collectors connected to a common draw box containing the regulator of the 5th organ of the picker with the regulator, the connected inputs with the generator and the sensor of the air mixture installed in the dust line behind the input zone to the coal Noah piti, air mixture temperature sensor is installed behind the entry area at a distance of 5-8 diameters of the dust pipe. In order to increase the speed, the temperature of the mixture of the aerosol is made in the form of a thermocouple with a bare hot junction. FIG. 1 shows a block diagram of the proposed device; in fig. 2 is a diagram of the air mixture temperature sensor; in fig. 3 shows the dependences of the constant time T and and the signal on the air mixture temperature on the distance between the coal fuel injection zone and the sensor. The device (Fig. 1) consists of, in common with the boiler unit (or housing), fuel regulator 1, breeders 2 signals, individual 82 fuel controllers 3 for X1 each burner, actuators 4, regulators 5 that change the supply of liquefied coal coal dust conduits to the burners from, aeration drinkers 6, pulverized coal to which comes from the intermediate bunker 7 of the pier and temperature sensors 8. The temperature of the mixture in. The dust duct is measured with a thermocouple with bare hot cnaet 9, which is located on the generatrix of the inner wall of the duct. For this, the protective cover 10 of the thermocouple is cut so that its edge goes inside the bob 11 to a depth of about 0.5 mm. The thermocouples of the 9 thermocouples are located exactly in the cut plane of the massive bob 11. To fix the thermoelectrodes along the cover axis and to avoid air leaks, the internal cavity of the thermocouple is sealed with an asbestos cord. The boss is welded into conduit 12 after thermocouple assembly. FIG. Figure 3 shows the dependences of the delay T and the time constant (inertia) T of the signal with respect to the air mixture temperature when the temperature sensor is installed at a different distance from the mixer. It has been established that the distance P 5-8 of the diameter of the dust pipe from the mixing point of the coal pipe with the transporting air of the thermocouple of the proposed design has the least inertia (T 10 s) and there is practically no delay (f 0). Installing an air mixture temperature sensor at a greater distance from the mixer of the driller leads to a significant increase in the delay and inertia of the signal. In indicated in FIG. Hydrodynamic and thermal stabilization of the air mixture flow is provided to 3 thermocouple installation points on the pipe line. The presented results allow recommending the installation of an air mixture temperature sensor at a distance of 5–8 diameters of the conduit from the mixer. The operation of the proposed automatic control device (Fig. 1) is as follows. With the help of a fuel regulator 1 common to a steam generator (or a housing) through multipliers 2 signals

3

control the setting of the individual fuel controllers 3, the controllers 3. maintain the specified performance of each user 6 by means of actuators 4 and regulators 5 by the mismatch between the driver signal of the control 1 and the signals of the sensors 8 installed in each dust pipe behind the mixing point of the transporting air and coal dust.

284

Thus, when installing an air mixture temperature sensor at a distance of 5-8 diameters of the pipe from the input of coal dust into it and filling it in the form of a thermocouple with a bare junction, the air mixture temperature reflects changes in fuel consumption with the least influence of interference and low inertia (FIG. 3). At the same time, the dynamic characteristics of thermocouples in operation remain stable.

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FIG. 2

Claims (2)

1. DEVICE FOR REGULAR0- ' ^: VANIA PRODUCTIVITY OF BOILER DUST SPRAYERS, connected to a common dust bin, containing a dust regulator regulating body with a regulator connected to the inputs to the setpoint and the air mixture temperature sensor installed in the dust pipe outside the input zone , in order to improve the accuracy of regulation, 'the mixture temperature sensor is installed behind the input zone at a distance of 5-8 diameters of the dust pipe. 2. The device according to π. 1, characterized in that, in order to improve performance, the air mixture temperature sensor S is made in the form of a thermocouple with exposed hot junction.