JPH0515929B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention melts industrial waste by blowing oxygen-containing gas for combustion from an air supply device into carbon-based combustible materials from a supply facility. The present invention relates to an industrial waste melting furnace configured to form a high temperature hearth.

[Conventional technology]

Conventionally, when introducing carbon-based combustible materials into a furnace, a constant amount of carbon-based combustible material was introduced at approximately constant intervals, the upper surface level of the high-temperature hearth was visually confirmed, and the upper surface level was maintained within a predetermined range. The amount and interval of feeding was adjusted by the operator's judgment.

[Problem that the invention seeks to solve]

However, it is actually extremely difficult or impossible to accurately maintain the upper surface level of the high-temperature hearth.
The following problems (a) to (c) were likely to occur, and there was room for further improvement.

(b) If the upper level of the high temperature hearth becomes too high,
Because a large amount of carbon-based combustible material is deposited in an unburned state above the combustion zone, CO ₂ from the combustion zone is reduced with C, producing a large amount of CO, which burns above the high-temperature hearth. Energy loss will be enormous.

(b) If the top level of the high temperature hearth becomes too low,
Due to the lack of combustible material in the combustion zone, the temperature of the high-temperature hearth decreases, reducing processing capacity.

(c) Because it is extremely difficult or impossible to control both the furnace top pressure and furnace bottom pressure as specified due to changes in the thickness of the high-temperature hearth, industrial waste and combustible materials may be mixed with the gas in the furnace when being charged. being blown out of the furnace,
Insufficient supply of high-temperature gas to the molten material discharge channel causes clogging due to solidification of the molten material, and excessive supply of high-temperature gas to the molten material discharge channel causes enormous energy loss.

An object of the present invention is to maintain the upper surface level of a high-temperature hearth at a predetermined level with good accuracy and reliability.

[Means for solving problems]

A characteristic configuration of the present invention is to detect whether the upper surface level of a high temperature hearth for melting industrial waste is a standard level, a high level above the standard level, or a low level below the standard level. a laser level detector is provided, and based on information from the level detector, when the upper surface level of the hot hearth is at the high level, more combustion oxygen is supplied to the hot hearth than when it is at the standard level. a first automatic control means for automatically operating the flow rate control means of the air supply device so as to increase the amount of gas blown into the air supply device; The second automatic control means is provided for automatically operating the input amount adjusting means of the supply equipment so as to increase the amount of carbon-based combustible material input into the high-temperature hearth, and its effects are as follows. be.

[Effect]

In other words, by using a laser-type level detector, it is now possible to automatically and accurately check the top surface level of a high-temperature hearth, which was previously thought to be impossible. Ta.

When the upper surface level of the high-temperature hearth reaches a high level, the amount of oxygen-containing gas blown for combustion is increased to increase the consumption of carbon-based combustible materials, and for example, the amount of input of carbon-based combustible materials is simply reduced. than,
The upper surface level of the high temperature hearth can be quickly returned to the standard level.

Also, when the top level of the hot hearth falls to a low level, increasing the input of carbon-based combustibles will quickly bring the top level of the hot hearth to normal levels, for example, rather than simply reducing the consumption of carbon-based combustibles. temperature of the high-temperature hearth can be suppressed.

〔Effect of the invention〕

As a result, it becomes possible to maintain the upper surface level of the high-temperature hearth with high accuracy and reliability, effectively preventing energy loss due to large amounts of CO generation and reduction in processing capacity due to a drop in the temperature of the high-temperature hearth. At the same time, it is possible to reliably control the furnace top pressure and the furnace bottom pressure, and in turn, it is possible to easily and effectively charge industrial waste and carbon-based combustible materials without blowing, and it is possible to control the furnace top pressure and furnace bottom pressure easily and effectively. By optimizing the amount of high-temperature gas supplied, clogging of the melt and energy loss can be effectively prevented.

In short, it has become possible to provide an industrial waste melting furnace that is even better in terms of operating costs, energy savings, and furnace performance.

〔Example〕

Next, an example will be shown with reference to FIGS. 1 and 2.

A hopper 2 for charging industrial waste and carbon-based combustible materials is placed between the upper and lower sides of the vertical furnace 1 and communicated via a double damper 3. It is configured to form a floor A. A nozzle 5 for supplying combustion air from the blower 4 to the high-temperature hearth A is attached to the lower part of the furnace with its outlet located below the top surface of the high-temperature hearth A and near the bottom of the furnace, and also for ignition. A burner 7 is attached to the lower part of the furnace.

The upper part of the furnace 1 is an ascending passage 8 for flue gas, and the lower part of the ascending passage 8 is connected with a tuyere 9 that supplies air from the blower 4 for after-combustion, and the ascending passage 8 is used for collecting exhaust gas. A cyclone 10 is connected by a duct 11.

A molten waste discharge passage 12 is connected to the bottom of the furnace,
A lid body 13 configured to allow recovery of industrial waste melted in the high-temperature hearth A and opening the bottom of the hearth.
is provided.

A conveyor 15 such as a belt type conveyor 15 that continuously conveys and supplies the carbon-based combustible material from the storage hopper 14 to the input hopper 2 at a thickness set by level adjustment of the gate 14a, and a storage hopper A conveyor 17 such as a screw type that continuously supplies a fixed amount of industrial waste such as mud from the damper 16 is provided, and a drive device 18 such as a hydraulic type that opens and closes the double damper 3 is provided. A program operating means 19 is provided that automatically operates the input operation of opening and closing the lower damper 3b after closing it at set time intervals, and thereby generates a standard amount of carbon-based combustible materials and industrial waste at set time intervals. It is configured to automatically feed into the furnace 1 one by one. The conveyor 17 is provided with an input amount setting means 20 for artificially changing and setting the feed amount of industrial waste, and the conveyor 15 is provided with an input amount setting means 20 for artificially setting the feed rate of the carbon-based combustible material by a setting device 21. An input amount adjusting means 22 is provided to adjust the amount of input according to the amount of supply.

The damper 23 that adjusts the amount of combustion air supplied from the blower 4 to the nozzle 5 is provided with a flow rate control means 25 that adjusts the opening according to the amount of blowing that is manually set by the setting device 24.

A laser level detector 26 that detects the level of the upper surface of the high-temperature hearth A based on whether the laser beam from the light projecting part 26a reaches the light receiving part 26b is arranged in three stages, with the light projecting part 26a and the light receiving part 26a arranged in upper and lower stages. Furnace 1
attached to the high temperature hearth A, the upper surface level of the high temperature hearth A is the upper (SLH) and lower (SLL) of the standard level (SL), the high level (HL) above the standard level (SL), and
The level detector 26 is provided with means 26c for determining which of the low levels (LL) below the standard level (SL) is, based on information from the light receiving section 26b.

Based on the information from the determination means 26c, when the upper surface level of the high temperature hearth A is at the high level (HL), the high temperature hearth A is higher than when it is at the standard level (SL).
so that the amount of air blown into the furnace is increased by the set amount, and the upper surface level of high temperature hearth A is at the standard level
Flow rate control means so that the amount of air blown into the high temperature hearth A is reduced by a set amount when the temperature is at the lower level (SLL) and the lower level (LL) than when it is at the upper level (SLH) of the standard level (SL). The first to give correction instructions to 25
Automatic control means 27 are provided. Also, based on the information from the determination means 26c, when the upper surface level of the high-temperature hearth A is at the low level (LL), the carbon-based combustible material is injected into the high-temperature hearth A more than when it is at the standard level (SL). A second automatic control means 28 is provided for instructing the input amount adjusting means 22 to correct the amount so as to increase the amount by a set amount.

In short, if the top surface level of high temperature hearth A reaches a high level (HL), the consumption of carbon-based combustible materials is accelerated by increasing the amount of air blowing, and the top surface level of high temperature hearth A is quickly corrected to the standard level (SL). However, if the upper surface level of the high-temperature hearth A reaches the lower level (SLL) of the standard level (SL), the consumption of carbon-based combustible materials is suppressed by reducing the amount of air blown, and the upper surface level of the high-temperature hearth A becomes lower than the standard level (SL). In addition, if the upper surface level of high-temperature hearth A becomes a low level (LL), an increase in the amount of carbon-based combustible material input will quickly return the upper surface level of high-temperature hearth A to the standard level (SL). It is configured.

[Another example]

The industrial waste inputted from the hopper 2 is, for example, various industrial wastes such as sewage sludge, tire scraps, municipal waste incineration ash, waste catalysts, etc., or their intermediate products, and the carbon-based combustible substances are, for example, coke. , briquettes such as anthracite, black smoke electrode scraps, etc.

Oxygen-enriched air, oxygen, etc. may be supplied from the nozzle 5 to the high-temperature hearth A, and in short, the structure may be such that oxygen-containing gas for combustion is blown into the high-temperature hearth A using appropriate air supply devices 4 and 5. Bye.

The specific structure for supplying carbon-based combustible materials to the high-temperature hearth A can be changed as appropriate, and they can be connected to the supply equipment 14,
Collectively referred to as 15, 2, and 3.

The specific configuration of the laser level detector 26 can also be selected appropriately, for example, the light projecting section 26a and the light receiving section 26b can be provided in two or more upper and lower stages.
In short, it is sufficient if there is a function to detect whether the upper surface level of the high temperature hearth A is a standard level (SL), a high level (HL), or a low level (LL).

Input amount adjustment means 2 for supply equipment 14, 5, 2, 3
2 can be changed to a method in which the conveyor 15 is operated intermittently to change the supply time per time, a time interval between opening operations of the damper 3 is changed, or any other suitable method.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, with FIG. 1 being an overall vertical sectional view and FIG. 2 being a conceptual diagram of a control configuration. 4, 5... Air supply device, 14, 15, 2, 3...
Supply equipment, 22...Input amount adjustment means, 25...Flow rate control means, 26...Level detector, 27...First automatic control means, 28...Second automatic control means, A
...High-temperature hearth.

Claims (1)

[Claims] 1. A high-temperature hearth A for melting industrial waste is formed by blowing oxygen-containing gas for combustion from the air supply devices 4 and 5 into the carbon-based combustible materials from the supply facilities 14, 15, 2, and 3. In the industrial waste melting furnace configured as follows, the upper surface level of the high-temperature hearth A is a standard level (SL), a high level (HL) higher than the standard level (SL), and the standard level (SL). ) is provided, and based on information from the level detector 26, the upper surface level of the high temperature hearth A is set to the high level. The flow rate control means 25 of the air supply devices 4 and 5 is configured to increase the amount of combustion oxygen-containing gas blown into the high temperature hearth A when the temperature is at the standard level (SL) than when the temperature is at the standard level (SL). a first automatic control means 27 for automatic operation, and a carbon system to the high temperature hearth A when the upper surface level of the high temperature hearth A is at the low level (LL) than when it is at the standard level (SL); The industrial waste melting furnace is provided with a second automatic control means 28 for automatically operating the input amount adjusting means 22 of the supply equipment 14, 15, 2, and 3 so as to increase the amount of combustible material input.