JPS5941407A - Dry dust separator for exhaust gas from blast furnace - Google Patents

Abstract

PURPOSE:To protect the packings and seals of valves in by-pass and slip-stream pipe lines, by providing a water atomizer in the by-pass pipe line to enable to control the temp. of exhaust gas. CONSTITUTION:The titled apparatus arranged in the order of a blast furnace 1, a separator 3 for removing dust of coarse particle side, a dry dust separator 4 and a turbine 9 for recovering the energy of pressure at the top of the furnace. A by-pass pipe line 12 for communicating the downstream side of said dust separator 4 to the slipstream side of the turbine 9 is provided, and water atomizers 14, 15 are provided in front and in rear of a septum valve 13 to atomize water into exhaust gas. In addition, sensors 17, 18 for detecting the temp. and pressure of the exhaust gas are provided at the upper stream side of the water atomizer 14 and moved conjointly with the water atomizers 14, 15. Furthermore, a sensor 19 for detecting the opening rate of the valve 13 is attached to the valve 13. By this apparatus, the temp. of exhaust gas flowing through the pipe line 12 is controlled, so that packing and seals are protected from heat.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dry dust removing apparatus for blast furnace exhaust gas in a furnace, and more particularly to a dry dust removing apparatus for protecting exhaust gas bypass pipes, septum valves, and the like.

Since blast furnace exhaust gas has a high temperature, considerable pressure, and a large amount of gas, various methods have been proposed to recover the energy contained in this exhaust gas. These methods
Classifying them according to the state of the exhaust gas, that is, the method of dust removal during the process in which the exhaust gas is supplied to the turbine, is as follows: (a) Wet dust removal method, in which the exhaust gas is removed with a Venturi scrubber, water is further sprayed into the exhaust gas as necessary, and then the exhaust gas is supplied to the turbine. It is broadly divided into dry dust removal method, which removes dust using dust catcher, bag filter, etc.

(b) generally has higher dust removal efficiency than (b), but the problem is that the exhaust gas temperature decreases due to contact with water, which reduces the energy recovery efficiency accordingly.

On the other hand, (mouth) is advantageous in that the exhaust gas temperature decreases less, but if the turbine stops for some reason,
In cases where the amount of exhaust gas increases rapidly, blast furnace exhaust gas may be allowed to flow at high temperatures through the existing bypass pipeline or downstream equipment connected to it, causing thermal expansion of the pipeline and heat resistance of packing and seals. It has the disadvantage of causing problems in terms of sexuality, etc.

Therefore, the present invention was developed in consideration of the current situation, and since the septum valve of the bypass pipe is moved, the bypass pipe can be quickly adjusted when the turbine is stopped, an increase in the amount of exhaust gas, or a change in exhaust gas temperature or pressure. It has features such as being able to control the exhaust gas flowing through the path.

That is, the dry dust removing device of the present invention can be used in a blast furnace, a coarse dust remover,
A dry dust remover and a furnace top pressure energy recovery turbine are arranged in this order via a pipe line, and a bypass pipe is provided that connects the downstream side of the dry dust remover and the outlet side of the turbine, and the bypass pipe is connected to the A water sprayer is provided in each of the pipes before and after the provided septum valve, and furthermore, an exhaust gas temperature and exhaust gas pressure detection sensor that is linked to these water sprayers is attached to the front, and a septum valve opening detection sensor is attached to the septum valve, respectively. That is.

The present invention will be explained below based on the embodiments shown in the drawings.

The exhaust gas discharged from the top of the blast furnace 1 passes through the pipe 2 and reaches a coarse dust remover B such as a dust catcher, where large dust particles are removed. The dust is sent to a dust remover 4 to remove dust.

Next, the line 5 is reached and the stop valve 6. It is sent to the turbine 9 via the emergency shutoff valve 7° and the speed control valve 8, and is converted into electrical energy by the generator 10. Exhaust gas exiting the turbine 9 is discharged to the outside of the system via a pipe 11.

On the other hand, in the present invention, a bypass line 12 is provided that connects the downstream side of the dry dust remover 4 and the downstream side of the turbine 9, and this bypass line 12 is provided with a septum valve 16.
Water sprayers 14 are installed on the upstream and downstream sides of the
and 15 are provided.

Preferably, a muffler 16 can also be provided downstream of the water sprayer 15 on the downstream side. This muffler 16 serves to reduce the loud noises produced by the septum valve.

Furthermore, in the present invention, an exhaust gas temperature detection sensor 17 and an exhaust gas pressure detection sensor 18 are provided on the bypass line in front of the water sprayer 14 on the upstream side of the septum valve 16, and the septum valve 16 is provided with a septum valve opening detection sensor. 19 is installed, and these sensors are connected to the injection water amount adjustment valve 2.
0 and 21, respectively. Normally, the septum valve 13 is closed and all exhaust gas is supplied to the turbine 9, but if the turbine 9 stops for some reason, or the amount of exhaust gas generated in the blast furnace 1 increases abnormally, or the gas pressure If there is an abnormal rise in the septum valve 13, the stop valve 6 and the emergency shutoff valve 7 are closed at the same time, and the load on the generator 10 is cut off. By opening the septum valve 16, the septum valve opening detection sensor 19 is activated immediately, and at the same time, the injection water amount adjustment valves 20 and 21 are opened, and water is sprayed into the exhaust gas by the water spray devices 14 and 15. It can be expected to prevent dust from adhering to the septum valve and the inside of the muffler, and also to remove such dust.

At the same time, the exhaust gas temperature is reduced.

Furthermore, the amount of sprayed ice is also controlled by an exhaust gas temperature detection sensor 17 and a pressure detection sensor 18, and when the exhaust gas temperature or pressure rises abnormally, the sensors 17 and 18 control the amount of water to be sprayed. Become.

As described above, in the present invention, by opening the septum valve 13, not only is a fixed amount of water sprayed immediately, but also the amount of water sprayed is increased or decreased in accordance with the temperature and pressure of the exhaust gas.

The exhaust gas cooled by the water spray is transferred to the pipe 22.
This prevents the exhaust gas from being discharged as a high-temperature exhaust gas.

Conversely, when starting the turbine 9, the stop valve 6 and the emergency shutoff valve 7 are opened, the septum valve 13 is squeezed, and the regulating valve 8 is opened to start the turbine 9.
The rotation of reaches steady state.

At this point, the generator 10 is rotated.

During this operation, the gas that has passed through the turbine 9 and the gas that has passed through the bypass line 12 are discharged from the system through the line 22 in a mixed state. However, when the septum valve 16 is closed, all the exhaust gas is comes to pass through the turbine 9. During this time, the exhaust gas temperature detection sensor 17 and the pressure detection sensor 18
The injection water amount adjusting valves 20 and 21 are controlled by the signal from the septum valve opening sensor 19, and finally the water spraying in the water sprayers 14 and 15 is stopped.

Furthermore, in the present invention, an injection water amount adjustment valve 20 is provided between the water sprayer 15 and the muffler 16 on the downstream side of the septum valve 16.
It is also possible to provide an exhaust gas temperature detection sensor 17A that works in conjunction with 21. This sensor 17A detects that if the exhaust gas temperature after water spraying is still rising, the amount of water sprayed is further added.

As described above, according to the present invention, since the septum valve 16 provided in the bypass pipe 12 is provided with a septum valve opening detection sensor, the water sprayer 14 is immediately activated without having to respond to the opening and closing of the septum valve 16. , 15 can be started or stopped.

Moreover, in the present invention, water spraying is not only started or stopped mechanically by opening and closing the septum valve 13, but also the exhaust gas temperature detection sensor 17 and the pressure detection sensor 18 in front of the water sprayer 14 on the upstream side. The amount of water sprayed can be automatically changed according to the temperature and pressure of the exhaust gas, so when the exhaust gas temperature and pressure are high, more water is sprayed, and when the exhaust gas temperature and pressure are low, less water is sprayed. , As a result, more efficient cooling of the exhaust gas is achieved.

Therefore, according to the present invention, since water is injected immediately according to the state of the exhaust gas flowing into the bypass pipe, there is no delay in water injection, and the temperature of the exhaust gas can be controlled by the bypass pipe or
It is possible to maintain the temperature of the exhaust gas pipes connected to the end of this bypass pipe below the design temperature, completely preventing these pipes from abnormal thermal expansion or thermal stress, and the gaskets and seals of each pipe and valve from being damaged by heat. can do.

[Brief explanation of the drawing]

The figure is a schematic diagram showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Blast furnace, 6...Coarse dust remover, 4...Dry dust remover, 9...Turbine, 12...Bypass pipe line, 16
...Septum valve, 14, 15...Water sprayer, 17
...Exhaust gas temperature detection sensor, 18...Exhaust gas pressure detection sensor, 19...Septum valve opening detection sensor. Agent: Patent Attorney Shin Ogawa − Patent Attorney Ken Noguchi Teru Patent Attorney Kazuhiko Saishita

Claims (1)

[Claims] A blast furnace, a coarse dust remover, a dry dust remover, and a furnace top pressure energy recovery turbine are arranged in this order via a pipe line, and a bypass pipe connects the downstream side of the dry dust remover and the downstream side of the turbine. A water sprayer is provided in each of the bypass pipes before and after the septum valve provided in the bypass pipe, and exhaust gas temperature and exhaust gas pressure detection sensors linked to these water sprayers are installed in the bypass pipe on the upstream side of the septum valve. 1. A dry dust removal device for blast furnace exhaust gas, characterized in that a segment valve opening detection sensor is installed in front of the water sprayer and on the septum valve.