JPS5947310A - Method for controlling water supply to drum in waste gas treatment device for converter - Google Patents

Abstract

PURPOSE:To suppress the reverse response phenomenon in the stage of starting a drum by determining beforehand the setting of the water level and integration time in a water level controller and the control conditions of a control valve for water supply and supplying water at one time. CONSTITUTION:The water level in a drum 4 during non-blowing is set by a setter C1 and the water level in the drum 4 during blowing is set by a setter C2. It is further detected by an AND circuit 21 that the treatment device is under blowing and that the flow rate of steam is large. If such conditions do not hold, a setter C3 is changed over to interrupt the operation output to a flow rate control valve 12 for water supply. The valve 12 is designed to be fully shut when no operation outputs are applied thereto; therefore, when the operation output to said valve is interrupted, the water supply to the drum 4 is stopped. The valve 12 is thus held fully shut during non-blowing but when the blowing is started, the valve 12 is largely opened and a large amt. of the water is supplied.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a top-blown or bottom-blown converter.
H) Z regarding the drum water supply control system for the batch process in V) the equipment.

As one of the dosing facilities, 2 r,! The zero converter was becoming well known,
This oxygen converter generates a large amount of gas during blowing.

This waste gas is a valuable gas that is partially contained in -L-carbon oxide gas, so it is recovered and used as a fuel (-, h
, ,reactor. The radiant part, which is a part of the flue in the 1st floor of the waste gas treatment facility in Kamataru Waste Gas Recovery (2/), is heated due to the high temperature of the waste gas, so a cold pipe is installed around it. , 11 The main body of the radiating section is protected by flowing water 1, also known as VC-. The cooling water is stored in the drum, passes through the pipe from the drum, is heated by the radiant section, and returns to the drum. Since the heated water flows out from the drum as atrophy, it is not possible to maintain a constant water level in the drum unless water is supplied separately.

By the way, one blowing time in an oxygen converter is about 1 hour.
The operation is short, about 5 minutes, and is run in batches (intermittently). Therefore, s(M ) 1q 1i(s ti iJ−
Heat exchange with the cooling water is also active during blowing, but declines during non-blowing. Therefore, 1. : Since the amount of water supplied to the drum also fluctuates, the amount of water supplied to the drum also changes intermittently.
I will do it.

This invention was developed under such circumstances.
Regarding the drum water supply 6□ control system, 2) consists of 111'', which has been designed to determine the operation of one person.

FIG. 1 is a schematic diagram showing a conventional drum water supply control system.

At the frontage, the cooling water passing through the radiant part 1 and the pipes wound around it can be heated, so it can be considered as a si-irer. There is a boiler 1, and inside it there is a cooling water pipe 2.
runs, and cooling water is sent through the pipe 2 by a bomb 3. Cooling water is supplied to the drums 1, 4IJ, etc. Therefore, steam is generated in the drum 4, and this steam flows through the steam pipe 5 by 1il.
lO is discharged. There, from water supply pipe 15 to Drano,
If the drum water level is not refilled, it is not possible to maintain a constant drum water level. Orifice 6 inserted into conduit 5
The first steam flow fi, measured from the differential pressure of the steam flow, is sent to the calculator 10 via the drum water level transmitter 8 and the drum water level transmitter 8 and the drum water level controller 19, respectively. be done. Performance: Q'1 with η'RR10, steam flow sewing v1
and the drum water level is I' shown by the following formula from the saving meter output V2.
t Conducted for 31 years.

A, I Vl -1-A2 (V2--1.1) -
v.

However, A1 and A2 Lt: tsoJl, / whichever is appropriate A) coefficient is 7[), B is the set water level for drum 4V /)
. ji'j j1 vessel 10 O・i 7] Item 7 - Result ■
c+ P-1, established 51/1+'7. Water supply k'-U1. 'N! 'Give to J section rule 11.

- force, the water supply flow rate (f) measured from the differential pressure of the orifice 14 inserted into the water supply line 15;
3 to measured value PV, and 2 to water supply rlf, :n:H”]
Send to Ini cut 11 12. Water supply +3iU Death H1
, 1 node 11, the operating output is set to Q in the direction in which the deviation between the set value Sv and the measured value 11+'+PV becomes zero, and 7, the water supply R1 is
'Control the valve opening degree of 11 and 12 l+II shift, water supply flow -F
4 as nl' member ii.

As described above, the water level in the drum during blowing is maintained at the set water level.

By the way, since the water supply control of the drum in the Kamataru converter waste gas treatment equipment is performed in a batch manner as described above, the water level fluctuations in C. It is known that the water level temporarily rises rapidly.This is because when the drum is started, a large amount of steam flows out from the drum 4, but due to the outflow of this steam, the water level of Drano. This is a phenomenon in which it increases in the opposite direction, and is called a reverse response phenomenon.

Such a phenomenon is of course not desirable from the standpoint of controlling the water level in the drum at a constant level over the entire load range of the boiler. Efforts are being made to eliminate the phenomenon.

This invention was made under these circumstances,
Therefore, the object is to provide a drum water supply control system that can inexpensively suppress the above-mentioned reverse response phenomenon without using a special compensation calculation device or the like.

According to the present invention, in order to suppress the sudden rise in the drum water level due to the reverse response phenomenon at the time of start-up, the above-mentioned purpose is to perform a seemingly reckless control of increasing the water supply amount instead of reducing it. This is achieved by reducing the amount of water (1'1) based on the water supply (due to the cooling effect).

In the present invention, in order to supply water for many weeks at the time of starting the drum, that is, at the time of reverse response, the operation output of the water supply valve during blowing, J-F, is equal to or greater than the amount of -5if formed by: airflow-river. If you leave the drum completely closed until the water level is fully closed, the water level set in the drum on the water level controller should be set to be sufficiently higher than the water level at the time when steam is generated during blowing or during non-blowing. - enough (l-(to have at least 1
one operation time, that is, the integration time, for the water level R''d node is set to be sufficiently long.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 282 is a graph showing, on the same time axis, the relationship between the blowing time of the converter, the drum water level, the steam flow rate, and the feed water h1 for detailed explanation of the present invention.

In the figure, X indicates the drum water level (mmL), YFi steam flow rate (t/h), Z indicates the water supply amount (t/h),
C1 is the setting value of drum water level adjustment n1 during non-blowing,
C2 modifies that during blowing to the above formula Z and setting value B
This is what determines the

As is clear from the figure, the water level d at Donno, during non-blowing, is V as shown by C1. V (higher than the previous step, for example, as shown in C2).
Second, r 150 mm < and Vζ are set in advance, respectively.

Then, at the time t2 when the operation is started and the internal pressure of the drum reaches a predetermined pressure, the steam flow rate Y increases rapidly, and based on this, the drano water level X also increases rapidly due to the reverse response phenomenon, so at this point t2"C The water supply h1Z is increased at once to suppress the reverse response phenomenon by the cooling effect. Also, in the shaded part, that is, from time t1 to time t12, the integral operation is performed over a long period of time, and the output of the water level adjustment H1 is increased to 100. %, even if the above setting is incorrect, the amount of water supplied will be large.

Note that to indicates the start of operation, and t3 indicates the end of operation.

Embodiment 4 of the present invention is shown in FIG. 3 (FIG. 1).

The control system shown in the same figure is different from the conventional system shown in FIG.
Setting to control q control valve 12? This is because a u'i 20 and a logic (AND) circuit 21 are provided.

That is, the water level of the drum (for example, set to -30On+tη) during non-blowing is set by the setting device CtK.
Also, use the setting device C2 to blow the air! that in (for example, 15
Set it to 0mm. ), and the AND circuit 21 detects that the steam flow rate is the same as that of the steam flow rate during blowing. This is to cut off the operational output to the flow rate control valve 12. Water supply control valve 11j,, Jl'74 will be fully closed if no operating force is given 4! When the C1 operation output connected to 'r,=i4 is cut off, the water supply to the drum 4 is stopped.

In addition, the drum pressure regulator 16 and the drum pressure control valve 1
7 is a control 11 so that the pressure of the drum 4 becomes a constant value B.
At the time of startup, it is detected that the pressure inside the drum is not at a constant value, and the control g1 valve 17 is opened to take out the steam generated inside the drum.

Therefore, at least during non-blowing, there is no operational output to the water supply control valve 12, and it is fixed to the setting device C3 side and the control valve 12 is fully closed, but when blowing is started and When the steam flow rate becomes large, the deviation of the current water level from the set water level in the controller 11 is sufficiently large, so the control valve 12 is opened wide and a large percentage of water is supplied.

In addition, there is no difference in other water level adjustment operations from those of the conventional system.

As described above, according to the present invention, in order to suppress the reverse response phenomenon when starting the drum, the settings of the water level and integration time in the water level controller and the control conditions of the water supply control valve are determined as described above. , - Since it has a simple configuration that only allows water to be supplied to the air, it can be realized using a normal controller, and it is also economical because it eliminates the need for a conventional inverse response compensation calculation device. This has the advantage of simplifying control and improving reliability.

Figure 1 shows the conventional Drano water supply system.
''' is also the main point, and Figure 2 shows the implementation of this invention (jl, l 7;
-Theory+7.1-A graph showing the relationship between the blowing time of the converter for J filtering, the water level of the drum L, the water level, +>imG, and the water supply oak on the same time axis, Figure 3 is a graph showing the implementation of this invention Soil, an example;
゛・1 Seita-Monguchi 1.

Code explanation 1...Boiler, 2...Cooling water pipe,
3...Pump, 4...Drum, 5...
... Steam pipe P3.6, 14 ... Orifice,
7... Steam flow work 4 and (, i P:, i, 8.
... Drum water level transmitter, 9 ... Drano, water level fake, Seri, 10 ... Arithmetic unit, 11 ...
・Water flow F, '1 tone? '1) Domain, 12... Water supply flow rate adjustment valve, 13... Water supply flow +1 transmitter, 15.
...Water supply pipe, 16...Drum pressure; for rice knots, 17...Drum pressure control valve, 18, 19
．． 20... Setting device, 21... Logical product circuit fee Jru person A buried earth Namiki l113 person agent patent attorney Matsu C・'・'j Kiyokawasaki City, Kawasaki-ku, Tanabeshinden 1 No. 1 Fuji Electric Manufacturing Co., Ltd. ■Applicant: Kawasaki Heavy Industries, Ltd. 3-1-1 Higashikawasaki-cho, Chuo-ku, Kobe City ■Applicant: Fuji Electric Manufacturing Co., Ltd. 1-43 Tanabeshinden, Kawasaki-ku, Kawasaki City −

Claims (1)

[Claims] Cooling water is supplied from the drum to cool the high-temperature I, 'f) gas released during blowing of the converter, and the cooling water is recovered from the drum while being heated. When the steam generated inside the drum reaches a predetermined pressure, it is taken out to the outside and sent to the utilization equipment, and the water that flows out as steam is supplemented (separately sent to the drum through the water supply control valve). Water-i, 4+; In the drum water supply control system 1 in the waste gas treatment system ff3 of the converter, the water level of the drum is detected, and the deviation 7' from the preset water level h; '-, a water level controller that outputs an operating output I5, a means for measuring the flow rate of steam flowing out from the 1゛ ram, a means for measuring the flow rate of water supplying water from the Doshimu, and the outputs of the water level M+, lJ moderator. a flow rate controller that adjusts the water supply flow rate by operating the water supply control valve so that the drum water level is maintained at the set water level; By satisfying the conjunctive conditions that blowing is in progress and that the steam flow rate exceeds D[-[4], the operating output of the flow controller can be transferred to the feed water control valve. and a switching means set so that the water level set in the water level adjusting mill is set in advance to be higher than the water level at the time when steam is generated during blowing;
Alternatively, during non-blowing of the converter, the water level that should normally be set should be set at a sufficiently low level (and N, both of which should be set at a sufficiently low level). If the setting is made for a sufficiently long time, and the amount of steam M1 in the drum during blowing exceeds a predetermined level, the switching means switches the operation output of the mud foot controller from the setting device side to the water supply control valve side, and the drum By supplying a large amount of water to the drum, the drum is cooled and a sudden rise in water level caused by the reverse response phenomenon is suppressed.
A drum water supply control system in a converter waste gas treatment device characterized by: