JPS6291709A - Method and device for burning humid pulverulent body - Google Patents

Abstract

PURPOSE:To make it possible to directly burn a fuel of a humid pulverulent body in a burner by forcibly extracting a high-temperature fluid from the vicinity of a combustion material outlet port of a combustion burner main body to mix the fluid with the humid pulverulent body, and supplying the mixture fuel to a fuel supply port. CONSTITUTION:A high-temperature fluid is forcibly extracted from the vicinity of a combustion material outlet port 7a of a combustion burner main body 7 by means of an injection nozzle 6 or the like. The high-temperature fluid is sprayed to the humid pulverulent body supplied from a humid pulverulent body service tank 1 via a predetermined quantity supplier 2 and a lock valve 3 to carry out evaporation of moisture contained in the pulverulent body by drying means such as an air current drying pipe 4 or the like. Further, in the temperature raised state, the humid pulverulent body is introduced into the main burner body via an integrator 5, a fuel injector 8 and the like. Accordingly, since the pulverulent body is ignited at a temperature higher than that for the ordinary dry pulverulent body, the combustion time is quicker and a complete combustion effect is achieved in primary and secondary combustion regions.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is intended to be used as a heat source for industrial furnaces in a broad sense, including heat sources for furnaces such as heat treatment furnaces and boilers, as well as heat sources for dryers, heat exchangers, etc. The present invention relates to a wet granular combustion method and apparatus particularly useful for burning a wet granular fuel such as oil coke in a burner and supplying high-temperature combustion gas or flame.

(b) Prior art and (c) Problems in the technology to be solved by the present invention Conventionally, granular solid fuels, such as pulverized coal such as oil coke, have a water content of approximately 20 to 30% in their normal form. It is normal to be in Therefore, such wet powder is generally dried in advance using a fuel such as kerosene and then burned.

Furthermore, in a combustion device for dry powdery solid fuel such as pulverized coal, it is common to use primary air to directly blow pulverized coal into a furnace using the combustion air blowing method. Various improvements have been proposed to the structure and shape of the burner, but it is difficult to obtain satisfactory results. It is practically impossible to avoid trouble, and furthermore, the combustion gas or flame that is formed is far from a completely burned and clean state, so it is important to avoid contamination and loss of the processed materials in the heat treatment furnace. The reality is that this is not possible in practice.

Here, the present inventor has completed a method of burning wet powder and granular material and an apparatus thereof using the burner device described above. That is, a high-temperature fluid is forcibly extracted from the vicinity of the combustion outlet of the combustion burner main body, the high-temperature fluid is mixed with wet granular fuel, and the wet granular fuel is heated and dried while being removed from the combustion burner main body. In this method, the fuel is supplied to a fuel supply port of a thoroughly moistened powder and granular material. Furthermore, it has the minimum basic elements necessary to carry out this method, namely, at least one combustion zone, with a fuel supply port at one end and a fuel supply port at the other end [1@
A combustion burner body having a combustion outlet, an injection nozzle for sucking and pumping high-temperature fluid from near the combustion outlet of the burner body, and an injection nozzle connected to a supply means for wet powder and granular material, and an injection nozzle for sucking and pumping high-temperature fluid from the vicinity of the combustion outlet of the burner body; The apparatus of the present invention comprises means for drying the wet powder and granular material engaged with the combustion burner body, and means for forcing the dried high-temperature powder and granular material together with air into the fuel supply port of the combustion burner main body.

Therefore, an object of the present invention is to make it possible to burn wet granular fuel directly in a burner, which was previously impossible, and to advantageously employ inexpensive granular solid wood fuel as the granular fuel. The combustion efficiency has been significantly improved, for example, about 55 to 65% compared to the use of electric oil fuel, about 65% compared to the use of LPG fuel, and about 30 to about 30% compared to the use of city gas fuel. It is an object of the present invention to provide a method and apparatus for combustion of wet powder and granular material that can reduce costs with a significantly reduced fuel ratio such as 50 cm, and can be completely automated.

Next, one embodiment of the wet powder combustion apparatus according to the present invention will be described in more detail based on the drawings.

FIG. 1 is a flowchart of a fully automatic combustion method that embodies the method of the present invention, in which 1 is a service tank for wet powder, 2 is a quantitative feeder, 3 is a lock valve, 4 is a flash drying pipe, 5 is an inch grater, 6 is an injection nozzle, 7fi combustion burner body, 8 is a fuel injection stirring device, 9 is a high temperature fluid outlet provided near the output side of the combustion burner body, 10 is an ignition burner, 11 is ignition It is an oil tank for. The wet granular material service tank 1 is provided with upper and lower level switches 101 and 102 on the side plates, and has a structure in which the wet granular material is transported from a transport device 103 to the upper part. Alternatively, a quantitative feeder 2 is connected to the bottom, and a feed motor 202 is engaged with a screw shaft 201. A lock pulp 3 is fixed to the supply port 203 of the quantitative feeder 2 to block entry of excess air. Lock valve 3 has its rotation drive sound, front screw shaft 2
01 is provided by a chain 301 and a sprocket gear 302 which are interlocked from the sprocket gear 204. A flash drying tube 4 is connected to the bottom of the lock valve 3. As shown in FIG. 3, this flash drying tube 4 is a cylindrical body having an upper opening 4a and a lower opening 4C, with a slightly tapered lower part and an opening 4b extending in the side wall tangent direction. It is equipped with A hollow tube 401 with an open top and bottom is provided inside the hollow, and the hollow tube 40
Hot air pipe 402 whose lower end is open and whose upper end is closed on the outer periphery of 1
is provided, and the opening 4b communicates with the hot air pipe 402. The dry fuel ejected from this flash drying tube 4 is connected to the opening 5a of the inch grater 5 by piping.
Here, it is further crushed and agitated and is sent under pressure to the fuel injection agitation device 8. The inch grater 5 is a crushing and stirring device consisting of fixed blades and rotating blades, and is rotationally driven by a drive motor 5b. The ignition burner 10 is started by an ignition device 10a operated by an electric signal, and is piped from an oil tank 11 via a gear pump and a valve 11bff driven by a motor 11a. The combustion burner body 7 forms a swirling flow in the combustion zone which proceeds in the direction of the combustion outlet. The primary combustion zone 7b has a plurality of secondary air supply nozzles 70- arranged in a manner similar to the above, and a plurality of tertiary air supply nozzles 71 connected thereto and arranged to form a similar swirling flow. The secondary combustion zone 7c has a high temperature fluid outlet 9 provided near the combustion material outflow lower a.
1 is formed from a pore opened in an air retaining jacket 72 that covers the entire combustion burner body 7 and bored in a refractory 73. Also, from this air jacket 72 to piping 72a1
It is connected to the secondary air supply nozzle 70 via a valve 74 and a valve with a control motor 75. In addition, air is force-fed to the air retaining jacket 72 by a turbo blower 16 driven by a motor 15, and is sent to the inflow lower 2 via a pulp 17 and a pulp with a control motor 18.
It is piped to a. 19 is a frame eye, 20 is a power supply circuit, 21 is a drive control circuit, 22 is a temperature control circuit, 2
3 is a temperature measuring element built into the furnace body A, which outputs a TC-2 signal to operate the drive control circuit 21 manually. Reference numeral 24 denotes a temperature measuring element provided in the primary combustion zone 7b of the combustion burner main body 7, which outputs a TC-1 signal and inputs it to the i-degree control circuit 22. 25 is a drive motor for a blowing turbo fan 26 of the injection nozzle 6.

With the above configuration, the first invention forcibly extracts high-temperature fluid from the vicinity of the combustion material outflow lower a of the combustion burner main body 7 using the injection nozzle 6,
The high-temperature fluid is sprayed onto the wet powder and granule material supplied from the wet powder service tank 1 via the constant supply device 2 and the lock valve 3, and the moisture is evaporated by a drying means such as a flash drying pipe 4. The present invention relates to a combustion method in which the fuel is heated and then introduced into the combustion burner main body via the inch grater 5, the fuel injection device 8, etc. in a heated state.

Therefore, it is ignited at a higher temperature than ordinary dry powder, has an extremely fast combustion time, and achieves a complete combustion effect in the primary and secondary combustion zones.

Next, the second invention relates to an apparatus for carrying out the first method, and as shown in the flow sheet of FIG. 1, the drive control circuit 21 and temperature control circuit 22 are completely unmanned. Combustion of wet powder becomes possible.

That is, the drive control circuit 21 controls the level detector of the wet powder service tank 1, that is, the upper and lower limit levelers 101, 1.
The LSI and LSL signals from 02 and the TC-2 signal from the temperature measuring element 23 suspended in the furnace body A are input, and the transfer device 1
03 level signal is fully output, and the drive motor 202 of the quantitative feeder 2, the drive motor 5b of the inch grater 5,
The drive motor 25 of the turbo fan 26 of the injection nozzle 6, the drive motor 15 of the turbo fan 16 for feeding air under pressure to the air retention jacket 72, and the temperature control circuit 22
In addition, the temperature control circuit 22 outputs all signals for driving and controlling the ignition oil tank 11, the gear pump motor 11a1, the ignition device 10a of the pulp llb and the ignition burner 10, which are adjacent to the gear pump motor 11a1, and the two control motors 18, 75 and inputs the TC-1 signal from the flame eye 19 and the temperature sensor 24. As described above, in the present invention, 20 to 30 inches of wet powder (for example, oil coke) In addition, the high-temperature combustion fluid can be sprayed into the flash drying tube 4 through the injection nozzle 6 to dry it and raise its temperature to make it easier to ignite. Since it is introduced into the burner in the form of granular fuel, it is extremely easy to ignite and the combustion effect is very poor.

Further, the granular fuel obtained in the above manner is entrained in the primary air, is forced into the fuel injection device 8 through the fuel supply port, and is ignited by the ignition means 10.

At this time, for example, by designing the solid fuel to be pumped along with the primary air along the cylindrical inner peripheral surface of the fuel injection device 8, a cyclone-like swirling flow state is created in the fuel injection device 8. can do. The swirling flow of the ignited solid fuel promotes uniform distribution of the fuel introduced into the primary combustion zone 7b throughout the zone.

The combustion flow of the granular fuel accompanied by this uniform dispersion promoting effect is generated by the primary combustion outlet formed by the secondary air supplied from the plurality of secondary air supply nozzles 70 in the primary combustion zone 7b. Due to the action of the swirling flow moving in the direction,
A very satisfactory primary combustion effect is produced. In other words, all sedimentation and accumulation of the fuel in the area 7b is forcibly suppressed, and the combustion state of the fuel under floating swirling agitation conditions is completely formed and maintained, and the combustion state is maintained with an appropriate floating residence time. Achieve ideal primary combustion effect. Then, in combination with the effect of the same swirling flow as described above proceeding in the direction of the secondary combustion material outflow lower a in the subsequent secondary combustion zone 7C, the complete gasification and combustion effect of the granular solid fuel is efficiently achieved.
make it possible to achieve.

At this time, for example, the amount of secondary air supplied to the primary combustion zone 7b is appropriately adjusted by the control motor 75, and the total amount t of the secondary air and secondary air is adjusted to an appropriate desired air level that is set in advance. It is possible to adjust the supply amount within the range, and thus set the silent combustion temperature in zone 7b to an appropriate generation condition for combustible decomposition gas, depending on the type and amount of granular fuel used, for example. I can do it. In addition, in the secondary combustion zone 7C, the amount of tertiary air supplied to the zone 7b is appropriately adjusted by the control motor 15 so that the combustion flow from the zone 7b is in a complete gasification combustion state. So, what is the total amount of air from the area 7b? It is possible to adjust to a suitable predetermined desired air supply rate range and thus to set the complete gasification combustion conditions depending on the overall combustion temperature in zone 7b and the state of the primary combustion stream. Note that the tertiary air is supplied in the form of preheated air used for heat exchange as cooling air in the air retention jacket 72.

The temperature control in the primary combustion zone 7b and the secondary combustion zone 7C can be changed appropriately depending on the type of granular fuel used, the view, and other conditions. In this step, the temperature of the zone 7c is adjusted to about 600° C. to mainly perform combustible decomposition and gasification of the fuel, and the temperature of the zone 7c is adjusted to about 1400° C. for the combustion flow from the zone 7b. The secondary combustion stream introduced into industrial furnaces can be adjusted to a complete gasification and combustion temperature of 100 mL, so that the secondary combustion stream introduced into industrial furnaces can be completely combusted, clean, and high-temperature combustion gas or flame.

[Brief explanation of drawings]

The drawings illustrate embodiments of the present invention; Fig. 1 is a flow sheet for carrying out the method of the present invention, Fig. 2 is a front view showing an example of the apparatus, and Fig. 3 is a sectional view of a flash drying tube. . 1. Wet powder service tank 2. Quantitative feeder 3. Rock pulp 4. Flash drying pipe 5. Inch grater 6. Injection nozzle 7. Combustion burner body 8. Fuel injection device 9.・High temperature fluid extraction port 10...Ignition burner

Claims (4)

[Claims] (1) Forcibly extract high-temperature fluid from the vicinity of the combustion outlet of the combustion burner main body, mix the high-temperature fluid with wet granular fuel, and heat and dry the wet granular material while heating the combustion burner. A wet powder combustion method characterized in that fuel is supplied to a fuel supply port of a main body. (2) A combustion burner body having at least one combustion zone and having a fuel supply port at one end and a combustion outlet at the other end, and sucking and pressurizing high-temperature fluid from near the combustion outlet of the combustion burner body. an injection nozzle for drying the wet powder and granular material, a means for drying the wet powder and granular material connected to the supply means for the wet powder and granular material and engaged with the high temperature fluid from the injection nozzle, and a means for drying the wet powder and granular material with entrainment of air. A wet powder combustion device comprising means for forcefully feeding fuel to a fuel supply port of the combustion burner main body. (3) In the wet powder combustion apparatus according to claim 2, the combustion burner body has a fuel supply port and an ignition means for igniting the fuel at one end, and a primary combustion stream at the other end. a primary combustion zone having an outlet; a plurality of secondary air supply nozzles provided on a side wall of the primary combustion zone and arranged to form a swirling flow proceeding in the direction of the primary combustion outlet; a secondary combustion zone having an inlet opening connected to the outlet of the primary combustion zone at one end and a secondary combustion outlet at the other end; 1. A wet granular material combustion apparatus comprising a plurality of tertiary air supply nozzles arranged to form a swirling flow proceeding in the outflow direction of the secondary combustion material. (4) The amount of feed of the wet powder to the drying means and the air of the injection nozzle are determined based on the electrical signal that detects the supply amount of the wet powder and the signal that electrically extracts the output temperature of the combustion burner main body. A drive control circuit that controls the amount and rotation amount of each operating motor of the pressure feeding means to the fuel supply port of the combustion burner main body, and also ignition based on the output temperature of the combustion burner main body and the temperature in the primary combustion zone of the combustion burner main body. 4. A wet granular material combustion apparatus according to claim 2, further comprising a temperature control circuit for controlling the amount of secondary and tertiary combustion air.