SU1028596A2 - Method for automatically controlling operation of unit for roasting sulfur-bearing raw material - Google Patents

Abstract

THE METHOD OF AUTOMATIC REGULATION OF THE WORK OF THE UNIT OF SURFUSED SURFACE RAW MATERIAL by the author. ST. 981800, characterized in that, in order to increase the reliability of the unit operation by improving the quality of regulation, when the upper limit value for the firing gas temperature is exceeded, at the outlet of the waste-heat boiler and flow control and temperature at the inlet of the heat-recovery boiler they affect drive otkhivayuschego device.

Description

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The invention relates to automatic production of chemical plants, in particular, to a method for automatically controlling the operation of a unit for burning sulfur-containing raw materials, and can be used in the chemical industry.

According to the main auth. 981800, a method is known for automatically controlling the operation of a unit for burning sulfur-containing raw materials, including a fluidized bed furnace and a waste heat boiler, by stabilizing the steam pressure in the drum of the waste heat boiler and changing the load on the fluidized bed furnace depending on the temperature difference between the fluidized bed and the roasting gas on the stove, and the vapor pressure in the boiler drum is correct; According to the temperature of the kiln gas at the outlet of the unit, in this case, upon reaching the boundary values of the vapor pressure, the furnace load fl is additionally adjusted.

However, in a known method, the disturbance is compensated without taking into account the type of these disturbances, which causes a violation of the static operating modes of the furnace.

The purpose of the invention is to improve the quality of control of the firing gas temperature at the exit of the firing unit and stabilize the static operating modes of the fluidized bed furnace.

This goal is achieved by the fact that, according to the method, when the upper limit value of the firing gas temperature at the outlet of the heat recovery boiler is exceeded and the flow rate and temperature at the inlet of the heat recovery boiler are controlled, the displacement device is actuated. . . .

The drawing shows the system that implements the proposed method

System a contains a boiling bed furnace 1, a waste heat boiler 2, a boiler drum 3, sensors 4.5 and b temperature, a computing device 7, a temperature difference controller 8, regulators 9 and 10, respectively, for blowing and sulfur-containing raw materials, regulating run organs 11 and 12, steam pressure sensor 13, steam pressure regulator 14 in the boiler of the heat recovery boiler, flow sensor 15 blow, actuators 16 and 17 of the raw material feeder and retrieving device, respectively.

The method is carried out in the following manner.

The signals from temperature sensors 4 and 5 installed in the fluidized bed and at the outlet of furnace 1, respectively, are sent to controller 8, in which ptVsHocTb LT is calculated.

(one)

Lt te

I h; equal it with a given value of at, determined by the value of dT

(2)

L.T.T.T-dT.

3

Where

- the temperature difference at which it is provided

a given concentration of sulfur dioxide in the calcined gas;

Trp is the temperature of the fluidized bed. The value of dT form the output signal G, according to PI - the law of regulation

/

CK -Qcic b 8l diC3)

where g

- the value of the output signal

regulator sc when equal

T.G;

K- and K- are the adjustment factors of the regulator; 0 t - time

Signal. and also the signal Gg from sensor b, measuring the flow into the furnace, is fed to the regulator 10, in which the difference AC is calculated

5; -o

L.

AND)

uC-Q UK GB

and form the output signal G

wed

for example, according to the PI law of regulation i

G --G, ° K, “LS,

(five)

Wed nsr-- about :;

where GO is the calculated kiln load

by blowing; G ° is the output signal of the regulator when, equality; K - coefficient of adjustment of the regulator. The signal Gf, o controls the pit drive. -G

bodies of sulfur-containing raw materials determined the number of revolutions and, thus, the load on the furnace for raw materials. The considered control system regulates the furnace load by raw material according to the temperature difference between the fluidized bed and the firing gas with a stable blow into the furnace, which ensures the maintenance of a given concentration of sulfur dioxide.

anhydride in roasting gas.

The load on the PSU furnace by blowing is stabilized at a given level as follows. The signal Gg from sensor 6, as well as the task G by

blowing is supplied to the input of the regulator 9, in which their difference is calculated

GB-G

(b)

uG

at

and form the output signal Ggp, for example, according to the PI-law of regulation.

Q6p-- V o V 9 Cie, ai, (7)

where (f is the signal on the regulator trigger;

K and K - adjustment factors

regulator.

The signal Ggj, served on the regulatory authority 11, installed on the supply line to blow into the furnace. The task of the controller 9 corrects the calculator Hbw by the device 7 according to the temperature of the firing gas at the outlet of the unit.

Regulators 9 and 10, together with the considered elements, form a furnace load control loop. Indeed, the correction of setting the regulator 9 causes a change in the flow rate to blow, and therefore, through the regulator 10 and a change in the supply of sulfur from the raw material to the furnace.

The vapor pressure in the drum 3 of the boiler-utilizer 2 stabilizes at a given value of the following way. The vapor pressure is measured by a sensor 13, the output of which RC and also the reference P are directed to the controller 14, from which the value of DF is calculated.

R RP - (8)

and form the output signal Pp, for example, according to the pi-law of regulation

PpPp% K 5UP K ,, (9)

about

where Рр is the signal at the output of the regulator,

, torus with P - 0; K and K are the coefficients of tuning the controller. The signal PP is fed to the regulatory authority 12 mounted on the steam line.

Correction of suspension by steam pressure in the drum and furnace load, as well as the formation of a signal for switching on the drive of the withdrawing device, is carried out in the computing device 7 with the deviation temperature of the kiln gas at the unit output from the preset level depending on the type of disturbing effect on the controlled value. For this purpose, signals are input to the input of the computing device 7: from the flow sensor 15, the kiln temperature from the sensors 5 and 6 at the inlet and outlet of the heat recovery boiler, respectively, and the setting of the firing gas temperature at the unit exit, blow into the furnace. Next, the adjustable parameter T is compared with the limited values of T and. tasks, calculate the difference of these values and calculate the values of P and Gg, for example, according to the PI-law of regulation

.Teb.K J Temat, ...

V (,,,,. Av.

where Pf and G are the values of P and GB, respectively, for & Tg | jj,

Kj; Kg; KJ; K - adjustment factors.

When the deviation of the adjustable pair. meters from the task by analyzing the input values reveal the type of disturbing effect and form the values of the output signals of the block. So

when T ,, ,, deviation beyond the lower boundary of the task, a disturbance acts along the firing gas channel at the boiler inlet - or the mash.

Initially, the setting of the vapor pressure stabilization circuit is changed, and upon reaching the upper pressure limit, the load on the furnace is changed.

Variable parameter deviation to the upper limit of the task

may cause a rise in the dust layer on the surface of the waste heat recovery boiler, as well as an increase in the temperature and / or consumption of firing gas at the inlet. If the conditions are fair

.G (. (- i :), (ID

. , where -t is time

t - constant,

This deviation of the controlled parameter is due to an increase in the amount of dust on the surface of the screen, since the latter reduces the heat transfer coefficient. Such a perturbation is compensated for by applying a signal N to turn on the driving device 17. If the reason for the deviation of Tgy from the task is an increase in the flow rate and / or temperature of the kiln gas, then the disturbance is compensated by a change in the steam pressure in the drum and the load on the furnace.

The proposed method of controlling the unit for firing sulfur-containing raw materials in comparison with the known ones by

the introduction of additional regulation of the impact of - the removal of the screens of the waste-heat boiler. from dust and the correction of steam pressure in the drum of the boiler and the load on the furnace, as well as

forming them depending on the type of disturbances by an adjustable value provides stabilization of the static operating modes of the fluidized bed furnace 1

reduction of the amplitude and duration of fluctuations in the temperature of the firing gas at the outlet of the unit, which improves the operation of the furnace and the heat recovery boiler, stabilizes

operating modes of the subsequent equipment, increases the technical and economic indicators of production.

Claims (1)

METHOD FOR AUTOMATIC REGULATION OF WORK OF FIRING UNIT OF FIRING SULFUR-CONTAINING RAW MATERIALS by ed. St. No. 981800, characterized in that, in order to increase the reliability of the unit by improving the quality of regulation, when the upper limit value for the temperature of the calcining gas at the outlet of the recovery boiler and the flow rate and temperature at the inlet of the recovery boiler are exceeded, the drive is affected shaking device. X Sb! 1 1028596 layers and roasting furnaces, and press boiler corrections * roasting