JPH0715323B2 - Operation control method of combustion device for solid fuel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an operation control method for a solid fuel combustion device for a small boiler using a solid fuel (abbreviated as RDF) produced from waste mainly composed of waste plastic. It is about.

[Prior art]

As a combustion device for fuel produced by processing waste, a combustion device for fuel, which is formed by compression molding waste mainly composed of waste wood and paper, is commercially available. The combustion device melts during combustion. It is not a combustion device that is suitable for fuel that is mainly made of waste plastic.

Further, as a combustion apparatus for coal or solid waste, there are a grate combustion furnace (spreader type, multi-type, etc.), a fluidized bed incinerator, etc., all of which are structures suitable for large-scale equipment. However, there are few devices that are easy to handle as miniaturized combustion devices.

Therefore, conventionally, the mainstream of combustion devices used for small boilers is to use petroleum fuel or gas fuel, which is easy to handle, and these are also excellent in terms of automation and safety.

[Problems to be solved by the invention]

When using RDF consisting of waste consisting mainly of waste plastics in the combustion equipment of small boilers, it is necessary to be excellent in terms of automation and safety as in the combustion equipment using petroleum fuel and gas fuel mentioned above. However, the existing operation control method of the solid fuel combustion device has a problem in terms of automation and safety.

Further, from a fixed rostrut having air holes as a solid fuel combustion device for burning RDF, a fuel supply pipe located below the rostrut for supplying solid fuel, and a screw arranged in the fuel supply pipe. There is also a bottom-filling type solid fuel combustor equipped with the following fuel supply device, but it is not suitable as a combustor for a small boiler due to problems in automation and complete combustion of fuel.

The present invention has been made in view of the above-mentioned problems, and eliminates the above-mentioned problems, complete combustion of solid fuel mainly composed of waste plastic, paper, wood, etc., and automatic ignition can be performed. It is an object of the present invention to provide an operation control method for a solid fuel combustion device that can be used as a combustion device for a fuel cell.

[Means for solving problems]

In order to solve the above problems, the gist of the present invention is to provide a rostrut having air holes and rotating on a horizontal plane, a fuel supply pipe located below the rostrut for supplying solid fuel, and a fuel supply pipe arranged in the fuel supply pipe. A method for controlling the operation of a solid fuel combustion apparatus, comprising: a fuel supply mechanism that includes a screw, an ignition burner that ignites solid fuel on a grate, and a secondary combustion burner that is provided above the ignition burner. When the ignition sensor and the secondary combustion burner are started after supplying an appropriate amount of solid fuel that becomes the ignition source at the start of the fuel by the fuel supply mechanism, and when the temperature sensor detects that the flame temperature has reached the specified value. Alternatively, the solid fuel for steady combustion is supplied by the fuel supply mechanism at the time when the flame temperature reaches a predetermined value, then the ignition burner and the secondary combustion burner are stopped, and the primary air supply device removes the primary air. And supplying the auxiliary combustion air supply and / or secondary air from the secondary air supply apparatus.

Further, the secondary combustion burner is stopped after a lapse of a predetermined time after the supply of the combustion air.

In addition, it is characterized in that the supply of the solid fuel that becomes the above-mentioned ignition source is controlled by the rotation speed or rotation speed of the screw and the operating time.

Further, the solid fuel combustion device is characterized in that the rostrut is rotated on a horizontal plane and is provided with a rostrul rotating mechanism, and the rostrul rotating mechanism is activated to control the timing of rotating the rostrut.

[Action]

The present invention, by performing the operating method of the solid fuel combustion device as described above, controls the initial combustion amount from solid fuel ignition to stable combustion, flame temperature, supply timing of combustion air and fuel supply timing, Further, by controlling the start / stop of the secondary combustion burner, it is possible to suppress the complete combustion of solid fuel mainly composed of waste plastic, paper, wood, etc., especially black smoke generated at ignition as much as possible.

Further, it is an operating method of a solid fuel combustion device that can perform automatic ignition and can be applied to a combustion device of a small boiler.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are views showing the structure of a solid fuel combustion device according to the present invention. FIG. 1 is a sectional view showing the overall structure of the solid fuel combustion device, and FIG. It is a partial cross section figure which shows a part.

In the figure, reference numeral 1 designates a grate, the grate 1 is of a bottom type, the upper surface of which is of a cap shape, and a large number of air holes 2 are formed on the surface. The tip of a fuel supply pipe 15 is connected to the lower central part of the grate 1, and the fuel supply pipe 15 is bent into an elbow shape, penetrates the furnace wall 20 and protrudes to the inside.
The fuel storage tank 4 is connected to the other end of the fuel supply pipe 15. A fuel supply screw 3 driven by a motor 21 is housed inside the fuel supply pipe 15.

When the fuel supply screw 3 is rotated by the motor 21, RDF
Solid fuel such as is supplied from the fuel storage tank 4 through the fuel supply pipe 15 onto the rostrtor 1.

The grate 1 has a structure capable of rotating at a low speed in the horizontal direction by a grate rotation mechanism as described later. The rostrut rotating mechanism includes a rack wheel 8 mounted inside the outer peripheral portion of the rostrut 1, a pinion 7 that meshes with the rack wheel 8, a bearing 9 that rotatably supports the outer circumference of the rack wheel 8, a reduction gear 6, and The motor 5 is provided, and when the motor 5 is started, its driving force is transmitted to the pinion 7 via the speed reducer 6, and the roster 1 is supported by the bearing 9 and smoothly rotates on it.

The primary air for combustion is supplied to the lower portion of the roster 1 by the fan 10 and is ejected by the air holes 2 formed on the surface of the rostr 1 to burn the fuel spread on the rostr 1.

Further, the secondary air is supplied to the combustion chamber 14 by the fan 11 through the supply pipe 12 and the air ejection holes formed on the surface of the link 13 arranged above the loss 1.

Here, two fans 10 and 11 are not necessarily required, and one fan may be used for both primary air and secondary air. Further, by supplying an appropriate amount of secondary air supplied to the combustion chamber 14 from an appropriate position, it is possible to burn without producing black smoke, and therefore, the mounting position of the link 13 for ejecting the secondary air is this. It is arranged in the combustion chamber 14 in consideration.

When the solid fuel contains a large amount of plastic, uniform ignition is very difficult due to lack of air and low ambient temperature at the time of ignition, resulting in generation of black smoke and uneven discharge of flame.

In order to solve this, LPG and LNG are set to almost the same height as Rostrul 1.
Alternatively, an ignition burner 17 using fuel such as oil is provided. A secondary combustion burner 18 using LPG, LNG, petroleum, or the like as a fuel is provided above the rostrut 1 in order to minimize the amount and time of generation of black smoke during ignition.

In the solid fuel combustion device having the above structure, when igniting the solid fuel, first, the motor 21 is started to drive the fuel supply screw 3 to supply an appropriate amount of fuel as ignition source to the rostl 1. This appropriate amount of fuel is supplied by controlling the rotation speed or rotation speed and rotation time of the fuel supply screw 3.

Ignition burner 17 after a proper amount of fuel is supplied to Rostrul 1
And operating the secondary combustion burner 18. The ignition timings of the ignition burner 17 and the secondary combustion burner 18 may be before or after, but it is preferable to operate the secondary combustion burner 18 first to prevent the generation of black smoke. If the secondary combustion burner 18 comes later, it is necessary to operate the ignition burner 17 within 30 seconds after the operation.

The flame of the ignition burner 17 is located approximately in the center of the upper part of Rostr 1
It is designed to reach the fuel that becomes a fire. Ignition burner 17
Due to this, solid fuel begins to burn and a flame is formed, but the temperature sensor 19 is set to measure the flame temperature.

After detecting that the temperature of the flame is 400 ° C. or higher, preferably 600 ° C. or higher, the fuel supply screw 3 is operated for steady combustion. For the flame temperature detection, a time at which the temperature reaches the predetermined temperature may be set based on experience, and the temperature sensor 19 may be used instead of the time setting.

After the fuel supply screw 3 is operated to shift to steady combustion, the fans 10 and 11 are activated within 1 minute to supply the primary air and the secondary air.

It is necessary to operate the secondary combustion burner 18 in order to suppress the generation of black smoke at the time of ignition as much as possible, but the extinguishing timing thereof is after the combustion of the solid fuel is stabilized. Experience has shown that about 10 minutes after restarting the fuel supply screw 3 is appropriate. Further, if the secondary combustion burner 18 is not used, black smoke is most likely to occur when the flame temperature at ignition rises and after the fuel supply screw 3 is restarted, so the secondary combustion flame is required during this period.

When the rostrut 1 is rotated horizontally on the bearing 9 at a low speed by the above-mentioned rostrul rotating mechanism, the supplied fuel A is spread evenly on the roster 1 as shown in FIG. 3, and as shown in FIG. , A pyrolysis zone B and a combustion zone C are formed,
A beautiful flame can be made. Therefore, since the purpose of the rotation of the roster 1 is to evenly disperse the fuel on the rostrut 1, the rostrul rotating mechanism may be rotated at a time when this is satisfied. The fuel supply screw 3 is preferably activated before or at the same time, but may be activated before or immediately after the restart.

Further, although the rostrut rotating mechanism is cooled by the combustion primary air, the wind box 16 below the rostrur 1 may have a water cooling wall structure in order to further protect the drive unit such as the speed reducer 6.

FIG. 5 is a diagram showing a flow of the ignition operation control of the solid fuel combustion. In the figure, first, the Rostrul rotating mechanism is activated to rotate the Rostrul 1 at a low speed (step 101). Next, the fuel supply screw 3 is activated for a predetermined time to supply solid fuel for ignition for ignition (steps 102 and 103).
Next, the fuel supply screw 3 is stopped (step 104),
Start the ignition burner 17 and the secondary combustion burner 18 (step
105), and then when the flame temperature reaches 400 ℃ (Step 10)
6) and restart the fuel supply screw 3 (step 10
7) Stop the ignition burner 17 (step 108). Subsequently, the fans 10 and 11 are activated (step 111), and the secondary combustion burner 18 is stopped (step 112). On the other hand, when the restart time of the fuel supply screw 3 in step 107 has elapsed (step 109), the fan 10 and the fan in step 111
When 11 is started and a predetermined time has passed (Step 11
0), stop the secondary combustion burner 18.

The secondary combustion burner 18 is provided to prevent black smoke at the ignition timing, but it can also be expected to function as a backup burner when stable combustion is required.

〔The invention's effect〕

As described above, according to the present invention, the initial combustion amount from solid fuel ignition to stable combustion, the flame temperature, the supply timing of combustion air and the fuel supply timing are controlled, and the secondary combustion burner is started and stopped. Therefore, it is possible to completely burn solid fuel mainly of waste plastics, paper, wood, etc., especially to suppress black smoke generated at the time of ignition as much as possible, and to perform automatic ignition. It is possible to obtain excellent effects such as being applicable.

[Brief description of drawings]

1 to 4 are views showing the structure of a solid fuel combustion device according to the present invention. FIG. 1 is a sectional view showing the overall structure of the solid fuel combustion device, and FIG. FIG. 3 is a partial sectional view showing a portion, FIG. 3 is a sectional view showing a part of the rostrur and a fuel supply pipe, FIG. 4 is a view showing a flame state of the rostrut, and FIG. It is a figure which shows the flow of operation control. In the figure, 1 ... Lostor, 2 ... Air hole, 3 ... Fuel supply screw, 4 ... Fuel storage tank, 5 ... Motor, 6 ... Reducer, 7 ...
Pinion, 8 ... Rack wheel, 9 ... Bearing, 10, 11 ... Fan, 1
2 ... Supply pipe, 13 ... Link, 14 ... Combustion chamber, 15 ... Fuel supply pipe, 16 ... Wind box, 17 ... Ignition burner, 18 ... Secondary combustion burner,
19… Temperature sensor.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-49-8074 (JP, A) JP-A-51-2268 (JP, A) Actually-opened Sho-58-185708 (JP, U)

Claims (4)

[Claims] 1. A fuel supply comprising a rostrut having air holes and rotating on a horizontal plane, a fuel supply pipe located below the rostrut for supplying solid fuel, and a screw arranged in the fuel supply pipe. A method for controlling the operation of a solid fuel combustion device comprising a mechanism, an ignition burner for igniting the solid fuel on the grate, and a secondary combustion burner provided above the ignition burner, wherein an appropriate amount of ignition source is provided. After the solid fuel of the above is supplied onto the rostrut by the fuel supply mechanism, the ignition burner and the secondary combustion burner are started, and when the temperature sensor detects that the flame temperature has reached a predetermined value or the flame temperature is predetermined. The solid fuel for steady combustion is supplied by the fuel supply mechanism at the time when the value becomes a value, then the ignition burner and the secondary combustion burner are stopped, and the primary air is supplied from the primary air supply device. And / or an auxiliary combustion air of secondary air is supplied from a secondary air supply device, the operation control method of the solid fuel combustion device. 2. The operation control method for a solid fuel combustion apparatus according to claim 1, wherein the secondary combustion burner is stopped after a lapse of a predetermined time after the supply of the combustion air. 3. The supply of the solid fuel as the ignition source is controlled by the rotational speed or rotational speed of the screw and the operating time of the screw, according to claim (1) or (2). An operation control method for a solid fuel combustion device. 4. The solid fuel combustion apparatus according to claim 1, wherein the solid fuel combustion apparatus comprises a rostrul rotating mechanism for rotating the rostrut on a horizontal plane, and the timing for rotating the rostral is controlled by activating the rostrul rotating mechanism. An operation control method for a solid fuel combustion device according to item (2) or (3).