JPS62242720A - Slurry-like fuel atomization burner - Google Patents

Abstract

PURPOSE:To enable a stable continuous combustion to be performed and to improve an efficiency of combustion even under a wide range of load by a method wherein atomizer which is suitable for a nature of fuel and an amount of injected fuel to get a superior fine particle formation of coal, water, slurry (CWS) and auxiliary fuel is attained, a closing of a fuel system is sensed in advance, the target is slid to prevent a closing of the system. CONSTITUTION:Fuel passes within a fuel supplying pipe 18, is changed from a ring-like flow passage 7 as a thin film ring form and injected toward a fuel injection hole 8, cut by atomized gas injected from an injection gas control part 4 composed of an atomized gas control ring 11 and a projection 13a, the fuel is made as fine particles and injected from the fuel injection hole 8 as a superior atomized fuel and finally ignited in a furnace. An area of each of openings of the atomized gas control part 4 and the fuel injection hole 8 is automatically controlled in response to a pressure within a connection pipe 46. An opening corresponding to each of the auxiliary fuel, purged fluid and CWS is automatically controlled in response to a load when CWS is ignited. A part of CWS is condensed and when a pressure within the connection pipe 46 is abnormally increased, both openings are wide opened to prevent a closing of the fuel injection hole 8 with CWS.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a spray burner for atomizing and burning a slurry fuel such as coal, water, and slurry (hereinafter referred to as CWS).

Conventional technology CWS is supplied under pressure to the burner of a boiler using a pump or the like, and like liquid fuel, it can be atomized with steam or air as an atomizing gas and then combusted.

However, since CWS contains a large amount of pulverized coal and is manufactured using water as a solvent and additives,
It has characteristics that should be taken into consideration when developing an atomizer, such as high viscosity, easy clogging in the nozzle, and the fact that pulverized coal particles are affected by the surface tension of water and are difficult to atomize.

CWS atomizers are still in the development stage, but they can be broadly classified into two types: external mixing type and internal mixing type. It is generally said that the internal mixing type has a better atomization state than the external mixing type.

Therefore, typical examples of the internal mixing type will be explained with reference to FIGS. 11 and 5.

In the figure, 31 is a slurry fuel passage, 32 is an atomizing gas passage, 33 is a fuel outlet, (4 is a flow path, 35 is a mixing chamber, 36 is an injection nozzle, = (7 is an atomizer, Slurry fuel pressure-fed from the slurry fuel passage 31 is ejected in a columnar manner from the fuel outlet 33 and merges with the atomizing gas from the atomizing gas passage 32, where it is mixed in the mixing chamber 35 and sent to the injection nozzle. It is atomized and ejected from 36 and burned in the combustion chamber.In this internal mixing type, it cannot be said that sufficient atomization has been achieved for twists with complicated structures.Also, heavy oil When switching from liquid fuel such as liquid fuel to CWS, or vice versa, it is necessary to replace it with a burner gun equipped with an atomizer suitable for each fuel due to the properties of each fuel. The top was also impractical.

For this reason, 1) the atomization state of CWS is poor, ignition is unstable, and combustion efficiency is low; 2) the amount of atomization gas used to improve the y & granulation characteristics is large; and 3) it is easy to clog. 4) It is difficult to obtain the jet nozzle velocity, etc., which is the optimum y & abduction condition depending on the increase or decrease of the injection jIffi. 5) Good atomization for liquid fuels such as heavy oil, etc. It has problems such as the difficulty of using it commonly as an atomizer obtained from gas.

Problems to be Solved by the Invention The present invention seeks to solve the above-mentioned problems, and thereby enables stable continuous operation of CWS combustion and improves the combustion efficiency of CWS even under a wide range of loads. Provides a burner with a high temperature and easy switching between CWS and heavy oil, etc.
The aim is to commercially popularize WS in small and medium-sized boilers.

Means for Solving the Problems The present invention provides an atomizer suitable for the properties of fuel and the amount of fuel to be injected in order to obtain good atomization of CWS and auxiliary fuel, and also detects the pressure of the fuel system. 11 is detected in advance and the target is slid to prevent it from opening.

Therefore, a spray gas control ring 11 having an annular groove 11a having a chevron-shaped cross section is provided inside the nozzle cap 10, which has a trumpet-shaped opening surface 10a formed on the inner periphery of the tip of the tubular body, and behind the opening surface. A ring-shaped flow passage 7 is formed at the tip of a fuel supply pipe 18 that is arranged concentrically inside the fuel supply pipe 18 to communicate with the rear fuel passage 48, and the injection
'lA body control ring 11 facing conical projection 13
A control member 14 is provided, and the control member 1
A cone-shaped target 15 is attached to the nozzle cap 4, and the fuel injection hole 8 is formed with the back surface 15a of the target facing the trumpet opening surface 10a of the nozzle cap 10.
Ga: U1M-4 J Le Shi^ Hitomi Biting 1s
/Iλノη-← Nri /Ii噌 Sasato-Shaichi A sliding mechanism 22 for moving the supply pipe back and forth is provided, and the rear end of the fuel supply pipe 18 is connected to the auxiliary fuel pipe 41. CWS supply pipe 43. connected to the connecting pipes 46 arranged in the order of the purge fluid supply pipes 45;
A detector 28 for detecting the pressure inside the connecting pipe is connected to the control system 25 of the sliding mechanism.

The fuel from the working connection pipe 46 is transferred to the fuel passage 4 in the fuel supply pipe 18.
8 and is ejected from the ring underground flow path 7 toward the fuel injection hole 8 in the form of a thin ring.
The fuel is cut and atomized by the spray gas ejected from the gas control unit 4, which is made up of the gas control ring 11 and the protrusion 13a, and is ejected from the fuel injection hole 8 in a good atomized state, where it is burned in the furnace. .

Since the opening areas of the atomized gas control section 4 and the fuel injection holes 8 are automatically controlled according to the pressure within the connecting pipe 46,
The openings correspond to each of the auxiliary fuel, the purge fluid, and the CWS, and the CWS combustion 11Sl';' lJ -P
n Haku1: i l? F, l', T white group h configuration
l? if M;1 k l! tl rl lo controlled.

Also, when the CWS is burned, a part of the CWS condenses and the connecting pipe 4
When the pressure inside IA'1 increases abnormally, both IA'1
0 is expanded even more to improve the circulation of CWS, and to prevent the fuel nozzle 8 from being blocked by CWS 111.

Embodiment An embodiment of the present invention will be explained with reference to FIGS. 1 to 3.

The nozzle cap 10 has a trumpet-shaped opening surface 10a on the inner periphery of the tip.
The other end is screwed into the burner outer tube 17.

Spout'll! The gas control ring 11 (hereinafter referred to as the steam control ring because steam was used as the atomizing gas) is a circular ring having an annular vortex 11a with a chevron-shaped cross section on its inner surface, and is fitted inside the nozzle cap 10 and is connected to the perforated plate 16. It is pressed and fixed to the back side of the opening surface 10a by a spring 12 interposed between the opening surface 10a and the opening surface 10a.

The control member 14 includes an outer fuel tube 13 whose rear end is screwed 5 to a fuel supply pipe 18, has a porous fuel passage 6 and a ring-shaped flow passage 7, and has a conical protrusion 13a at its tip.
The collar for fixing the burner outer tube 17 is composed of a part and a part.
are located concentrically.

The control member 14 has a truncated conical shape and is fixed to the center of the control member 14 with a screw 15b, and its back surface 15a
A ring-shaped fuel ejection hole 8 is formed opposite to the opening surface lOa of the nozzle cap 10.

The perforated plate 16 is an annular ring having a plurality of steam communication holes 2 formed on its circumference, and its outer periphery is clamped and fixed by the nozzle cap 10 and the burner outer tube 17.

The burner outer tube 17 is a cylinder that forms a steam flow path 1 between its inner peripheral surface and the outer peripheral surface of the fuel supply pipe 18, and a tube seat 17a that communicates with the steam flow path 1 is provided on the outer peripheral surface. A backing 20 is fitted on the end face to prevent leakage of steam, and is fixed with a cap nut 19.

The fixed frame 21 is fixed to the cap nut 19 and rotatably holds a sliding peg 22c behind the cap nut 19. The m-motion nut 22c has a female thread 22a carved in the center, and a lever 22b fixed to the outer peripheral surface.

A tube body 23 having a male thread 23b on its outer periphery that engages with the female thread 22a is fixed to the outer circumferential surface near the rear end of the fuel supply pipe 18 with a bolt 23a.

Therefore, the sliding mechanism 22 is constituted by the aforementioned 22a, 22b, 22c, and 23.

The lever 22b is connected to a link mechanism 26, and the control member 14. 15 and the fuel supply pipe 18 are moved forward and backward.

Therefore, the control system 25 of the sliding mechanism 22 is constituted by the above-mentioned 26 and 27.

The fuel supply pipe 18 is connected to a connecting pipe 46 via an expansion joint 47, and a pressure detector 28. Branch pipes 49, 41, 43, and 45 are connected in series so that soil for heavy oil, etc. for auxiliary fuel is arranged.

The pressure signal from the pressure detector 28 is transmitted to the control system 25.
It is now sent to

In the burner of the present invention configured as described above, when burning heavy oil or the like as auxiliary fuel, the stop valve 40 becomes a problem, and the auxiliary fuel is passed from the connecting pipe 46 through the fuel passage 48 to the porous fuel passage 6. ．． (Tagera via ring-shaped flow path 7)
The liquid is discharged toward the back side of 15 in a thin film ring shape. On the other hand, steam is supplied from the steam port 17a to the burner outer pipe 17. X air hole 2
The steam reaches the st'a section 4, and is jetted out from there to atomize the fuel while cutting the thin ring-shaped fuel, and is sprayed into the furnace from the fuel jet hole 8. In this case, the clearances between the fuel nozzle hole 8 and the steam control section 4, which greatly affect the atomization characteristics, are controlled to the narrowest values 11 and t, respectively.

Next, the stop valve 40 is turned off, the purge fluid stop valve 44 is opened, and the auxiliary fuel is purged.

Accumulation 1? 11 le 1? ! I, To40ha Δ Le tank 1ν 1
．． ru/Q -1 light A rill open. The CWS contains a large amount of coal fine particles, and the intervals between the above and t indicate that there is a possibility that the ejection hole 8 will open due to the CWS.

Therefore, the combustion amount of CWS is reduced by 10 by the 'tM movement mechanism 22.
In the case of 0%, the interval between the fuel nozzles 8 is automatically changed from h to 11, and the interval between the steam control parts 4 is also changed from t to T, resulting in a state suitable for CWS combustion. CW in this case
For the flow of S, the stop valve 42 is open, the stop valves 40 and 44 both act as a lock, and the CWS is in the pipe 43.

46 to 47. The fuel is discharged from the ring-shaped flow 'ttS7 to the back side of the target 15 in the form of a thin film ring through the porous fuel passage 6 of the fuel supply pipe 18. On the other hand, steam is discharged from the steam port 17a to the burner outer pipe 17. The CWS is passed through the steam communication hole 2 and reaches the steam hole 1g1 section 4, where it is ejected to cut the thin ring-shaped fuel and atomize the CWS, which is then sprayed into the furnace through the fuel injection hole 8.

When the combustion amount of the CWS changes, the clearances of the fuel nozzle hole 8 and the steam control section 4, which have dimensions that greatly affect the atomization characteristics, are from H, from 1゛ to t, and from the fuel supply pipe. By advancing 18 and retracting 1, 17 is properly controlled.

If a blockage occurs in the fuel nozzle hole 8 during combustion of the CWS, most of this blockage will occur in a part of the fuel nozzle hole 8 due to the CW
Some of the coarse particles of the coal particles containing a large amount of S or particles appear to aggregate with each other, causing a partial blockage, which grows and eventually leads to a complete blockage. Therefore, at the stage of partial blockage, the pressure in the CWS flow path is detected by the pressure detection 7928, and the interval between the fuel nozzle holes 8 is automatically set to the maximum H', and the steam control section 4 is also set to T'. This is to prevent store openings in advance.

Effects of the Invention According to the present invention, when burning auxiliary fuel such as heavy oil at startup, the burner is equipped with an atomizer that matches the properties of the auxiliary fuel, and when CWS burns, it automatically sets the optimum atomizer according to the amount of combustion. At the same time as the spray speed is obtained, the amount of atomizing gas is also controlled, and as a result, high combustion efficiency can be obtained in each negative combustion chamber, and the amount of atomizing gas consumed is low.
This can be detected at the beginning of the blockage at the stage 11)1, and the blockage can be prevented in advance, which has a great effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a slurry cane fuel spray burner according to the present invention, FIG. 2 is a partially enlarged sectional view thereof, FIG. 3 is a front view, FIG. 4 is a sectional view of a conventional burner, and FIG. The figure also shows a sectional view of another conventional burner. 7... Ring-shaped flow path, 8... Fuel injection hole, 10...
... Nozzle cap, 10a... Opening surface, 11...
Atomizing gas control ring, lla...ring 1λ groove, 13a...
...Protrusion, 14...Control member, 15...Target, I5a...Target backside, 18...Fuel supply pipe, 22...Sliding mechanism, 25...Control system, 28...・
Pressure detector, 41... Auxiliary fuel pipe, 43... Slurry fuel supply pipe, 45... Purge fluid supply pipe, 46.
... Connecting pipe, 48... Fuel passage,

Claims (1)

[Claims] (1) Inside a nozzle cap with a trumpet-shaped opening formed on the inner periphery of the tip of the tubular body, a spray gas control ring having an annular groove with a chevron-shaped cross section is provided behind the opening, and is concentric with the inside of the nozzle cap. At the tip of the fuel supply pipe installed in
A control member is provided, which forms a ring-shaped flow passage and communicates with the rear fuel passage, and has a conical protrusion formed at its tip facing the atomized gas control ring; A target having a shape of the shape is attached, the back surface of the target is opposed to the trumpet-shaped opening surface of the nozzle cap to form a fuel injection hole, and a sliding mechanism for moving the fuel supply pipe back and forth is provided in the rear part of the fuel supply pipe, The rear end of the fuel supply pipe is connected to a connecting pipe arranged in this order: an auxiliary fuel pipe, a slurry fuel supply pipe, and a purge fluid supply pipe, and a detector for detecting the pressure inside the connecting pipe is connected to the sliding mechanism. A slurry fuel spray burner characterized by being connected to a control system.