JPS62190315A - Method and device for spraying slurry-like fuel - Google Patents

Abstract

PURPOSE:To reduce an amount of gas for spray working and to improve combustion efficiency, by a method wherein coal and water slurry (CWS) is fed through a conduction passage with a pressure, a fission atomization, wherein CWS is injected at a throttle part to a target for collision, and atomization, wherein an eddy flow is collided with a groove formed in the outer periphery of the target, take place. CONSTITUTION:Coal and water slurry (CWS) is fed with a pressure through a conduction passage 11 to a single hole 13 of a throttle part, the CWS is throttled at the throttle part to form a high speed single liquid column, which is injected in a mixing chamber 15. The liquid column is collided with a target 18 positioned facing the single hole and is fission-atomized for primary atomization. An eddy flow is exerted on the CWS within the mixing chamber 15 by means of atomized gas fed through a flow passage 14 communicated with a gas conduction passage 12 for atomization. The eddy flow is collided with a groove, formed in the outer periphery of the target, when it flows through the mixing chamber, and is agitated for promotion of atomization. The CWS is sprayed through a spray nozzle 16 into a furnace 19 in a state to be sufficiently atomized. This constitution enables improvement in combustion efficiency of the CWS without needing quantities of gas for spray working.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a IIIjf method and apparatus for atomizing and combusting a slurry fuel such as coal, water, and slurry (hereinafter referred to as CWS). be.

Conventional technology CWS is pressurized and supplied to the burner of a boiler by a pump or the like, and like liquid fuel, it can be atomized with steam or air and combusted as a spray operating gas.

However, since CWS is manufactured by containing multiple layers of pulverized coal, using water as a solvent, and adding several types of additives, it has a high viscosity, is easily clogged in the nozzle, and has a high viscosity. Coal particles are affected by the surface tension of water and are difficult to atomize, and when CWS is heated outside of the appropriate temperature range, it will aggregate and increase viscosity, which are characteristics that should be taken into consideration when developing an atomizer. There is.

CWS atomizers are still under development, but they can be roughly divided into two types: an external mixing type and an 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. 5 and 6.

In the figure, 1 is a slurry fuel passage, 2 is an atomizing gas passage, 3 is a fuel outlet, 4 is a flow passage, 5 is a mixing chamber, 6 is an injection nozzle, and 7 is an atomizer. The slurry fuel pumped from 1 is jetted out from the fuel outlet 3 and merges with the exposing gas from the atomizing gas passage 2.
The mixture is mixed in a mixing chamber 5, atomized and ejected from an injection nozzle 6, and combusted in a combustion chamber. In this internal mixing type, although the structure is complex, it cannot be said that sufficient atomization has been achieved yet.

For this reason, 1) The atomization state of CWS is poor and the combustion efficiency is low.
) There are problems in that the consumption amount of the atomizing gas used to improve the atomization characteristics is large; and (3) it is easy to clog.

Furthermore, although it has been proposed to heat CWS, the purpose is often to lower the viscosity, and it has not been able to achieve a sufficient effect.

Problems to be Solved by the Invention The present invention solves the above-mentioned problems in CWS atomization, namely, the increase in fuel cost due to poor atomization state of CWS and low combustion efficiency, and to improve the atomization characteristics. This method solves problems such as the need for a large amount of atomizing gas, which increases the cost of atomization, and the complexity of the nozzle structure, which tends to cause blockages due to atomized coal particles. This enables stable continuous operation of CWS combustion, and
The aim is to improve the combustion efficiency of S and to promote commercial use of CWS in small and medium-sized boilers.

Means for Solving the Problems The present invention uses a single-hole CWS injection port to prevent clogging, and injects a portion of the power required to increase the pressure of the CWS toward a target in the mixing chamber, causing the target to collide. By effectively utilizing the action of splitting and atomization, the CWS is already split and atomized, so the subsequent supply of spray operating gas is less necessary, and the outer periphery of the target inserted into the mixing chamber is reduced. The above-mentioned problem is solved by further promoting atomization by the agitation 1 and collision effect due to the shape of the particle.

Therefore, the atomizer main body is removably connected to the tip of a supply conductor that has a first passage that is a conduction path for the CWS and a second passage that is a conduction path for the atomizing gas on the outside thereof.
The atomizer main body includes a target having a groove-shaped outer periphery, a mixing chamber, a single-hole flow path of a constriction portion communicating with the first passage, and a plurality of flows communicating with the second passage to provide a swirling flow in the mixing chamber. and a spray nozzle having a plurality of holes for spraying atomized fuel, and the target has an adjustable distance from the constriction part and is detachably screwed into the spray nozzle. .

The working CWS is forced into the CWS conduit and is injected by the throttle part in the form of a single liquid column toward a target provided in the center of the mixing chamber along the axial direction of the mixing chamber, and is split by colliding with the target. By introducing the atomizing gas from the peripheral wall of the mixing chamber in a direction tangential to the wall of the mixing chamber, a swirling mixed flow is formed in the mixing chamber, and the target inserted into the mixing chamber is Atomization is promoted by the stirring action of the grooves on the outer periphery of the atomizer and the atomizer is sprayed from the atomizer nozzle.

Embodiment An embodiment of the present invention will be explained based on FIGS. 1 to 4.

FIG. 4 shows a CWS supply system applied to the CWSO blowing method and device according to the present invention.
Tank A, CWS pressure feeding device B such as a pump, strainer C, flow meter, and atomizer E that sprays CWS.
etc.

1 and 2 show an atomizer according to an embodiment of the present invention.

This atomizer includes a CWS conduction path 11 provided at the center of the supply conductor 10 to which the CWS from the flow meter side is pumped, and a CWS conduction path 11 provided outside the path 11 to which compressed gas from a compressor (not shown) is pumped. a supply conductor 10 consisting of an atomizing gas passage 12; a mixing chamber 15; a single hole opening 13 of a constriction portion that communicates the passage 11 and the mixing chamber 15;
and the flow paths 14A and 14 that communicate with the mixing chamber 15, and the target 18 provided at the center of the mixing chamber 15 and facing the single hole opening 13.

The atomizer main body 20 mainly includes a spray nozzle 16 that opens a mixing passage into a furnace 19 .

A member 21 having the single hole opening 13 of the constriction part and the flow path 14A, the flow path 14 located in front of the member 21, and the mixing chamber 1
The atomizer main body 20 includes a member 22 including a part of the mixing chamber 15 , a member 23 including the remainder of the mixing chamber 15 located in front of the member 22 , a jet nozzle 16 , and a target 18 . By screwing it into the supply conductor 10, it is configured to be detachable from the supply conductor 10.

A plurality of the flow passages 14 are provided in a direction such that a spiral mixed flow is formed in the mixing chamber by introducing the spray operating gas from the peripheral wall of the mixing chamber 15 in a direction tangential to the wall of the mixing chamber. It is being

Further, the target 18 is detachably attached to the spray nozzle so that the distance from the constriction part can be adjusted by screwing into a target mounting screw hole 17 formed in the member 23. As shown in the figure, a spray nozzle 16 is arranged at the center of the member 23, and a spray nozzle 16 is arranged on the outer periphery of the member 23.
are provided at equal intervals.

Furthermore, as shown in FIGS. 3a, b, and c, the target 18 consists of a head 18A, a mounting screw part 18B screwed into the target mounting screw hole 17, and a mixing chamber insertion part 18C. A groove is formed on the outer periphery of 18C, and this groove is formed by a plurality of lines (C) of the mounting screw portion 18B.

The CWS in the CWS tank A is sent by a CWS pressure feeding device B such as a pump to an atomizer E that sprays CWS via a strainer C2 flow meter, and is atomized and sent to a furnace 19.
It is sprayed on and used for combustion.

The CWS that has passed through the flowmeter is fed under pressure from the conduction path 11 to the single-hole port 13 of the constriction section, is throttled by the constriction section, and is injected into the mixing chamber 15 as a single high-speed liquid column, which is located on the opposite side of the single-hole port. The particles collide with the target 18, and are split and atomized by the action of the collision, resulting in primary atomization.

Next, the CWS is given a swirling flow in the mixing chamber by the atomizing gas supplied from the flow path 14 communicating with the atomizing gas conduit 12 . When this swirling flow passes through the mixing chamber, it hits the grooves formed on the outer periphery of the targera (1B) and is violently stirred, further promoting atomization. sprayed inwards.

Effects of the Invention According to the present invention, the CWS is sufficiently atomized by splitting and atomizing by collision with the target and atomizing by the swirling flow hitting the grooves formed on the outer periphery of the target. Therefore, the supply of the atomizing gas is much smaller than in conventional atomization methods and devices, resulting in high combustion efficiency.

In addition, since the CWS is squeezed by the constrictor and injected into the mixing chamber as a single high-speed liquid column, the single-hole port will not become clogged.

Further, since the target is screwed in, the distance between the target and the throttle part can be adjusted depending on the amount of CWS supplied and the state of the slurry.

Furthermore, since the atomizer main body is detachably connected to the supply conductor, and the target is screwed in as described above, the inside of the atomizer can be easily cleaned and replaced.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an atomizer according to the present invention, Fig. 2 is a front view thereof, Fig. 3 is a side view of various targets, and Fig. 4 is a sectional view of an atomizer according to the present invention.
The figure shows a supply system diagram of the CWS, FIG. 5 shows a sectional view of a conventional atomizer, and FIG. 6 shows a sectional view of another conventional atomizer.

Claims (4)

[Claims] (1) Slurry fuel consisting of a mixture of solid and liquid is pumped into a slurry fuel conduit, and a constriction section directs the slurry fuel into a single stream along the axial direction of the mixing chamber toward a target provided at the center of the mixing chamber. The slurry fuel is injected in the form of a liquid column and collides with a target to split and atomize the slurry fuel, and then the spray operating gas is introduced from the mixing chamber peripheral wall in a direction tangential to the mixing chamber wall, creating a spiral mixture inside the mixing chamber. A method of spraying slurry-like fuel, which comprises forming a flow and further promoting atomization by a stirring action by a groove on the outer periphery of the target inserted into a mixing chamber before spraying. (2) The atomizer body is removably connected to the tip of the supply conductor, which has a first passage that is a passage for slurry fuel and a second passage that is a passage for atomizing gas outside the supply conductor. The atomizer body includes a target having a groove-shaped outer periphery, a mixing chamber, a flow path having a single hole in a constriction portion that communicates with the first passage, and a plurality of flow passages that communicate with the second passage and provide a swirling flow within the mixing chamber. and a spray nozzle having a plurality of holes for spraying atomized fuel, the target comprising:
A spraying device for slurry fuel, characterized in that the distance between the throttle portion and the throttle portion is adjustable, and the spray nozzle is detachably screwed into the spray nozzle. (3) The slurry fuel spraying device according to claim 2, wherein the grooves formed on the outer periphery of the target are grooves extending in the axial direction of the target. (4) The slurry fuel spraying device according to claim 2, wherein the grooves formed on the outer periphery of the target are grooves in the radial direction of the target.