JP2000266336A - Manufacturing apparatus for paste-form fuel and method for feeding slurry fuel to pressurized fluidized bed boiler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve a problem on adhesion of CWP by a method, wherein a viscosity measuring device is provided to measure CWP viscosity over a long time in a manufacturing process of CWP and each part is cleaned by a cleaning device. SOLUTION: In a coal/water paste manufacturing device provided with a device to measure viscosity of CWP, injection nozzles 51a and 51b are provided to clean a guide plate 105 for introducing CWP attached to a CWP viscosity measuring device, a viscosity measuring container 106, and a rotor 110 for detecting viscosity. Water is poured on the guide plate 105, the viscosity container 106, and the rotor 110 through water injection nozzles 51a and 51b each time a kneader is stopped, and periodic cleaning through injection is executed during the operation of the kneader.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to combustion of solid fuel in a pressurized fluidized bed, driving of a steam turbine by generated steam, and further driving of a gas turbine by high-pressure, high-temperature combustion gas to achieve high-efficiency power generation. And a pressurized fluidized-bed boiler combined cycle power plant.

An apparatus and method for producing a solid fuel and water mixture to be supplied to a pressurized fluidized bed combustion furnace, and further relates to an apparatus for supplying the fuel to a fluidized bed combustion furnace, particularly for supplying paste fuel. The present invention relates to a supply nozzle structure of a preferred boiler device.

[0003]

2. Description of the Related Art Fuel is burned in a fluidized bed furnace in a pressurized state to generate steam in a heat transfer tube installed in a fluidized bed to drive a steam turbine, and further generated in a pressurized fluidized bed boiler. There is known a pressurized fluidized-bed boiler combined cycle power plant capable of driving a gas turbine with high-pressure and high-temperature combustion gas to obtain electric power with high efficiency.

One of the problems with the pressurized fluidized bed boiler is to continuously and stably supply a large amount of coal particles into a pressurized fluidized bed furnace. As means for solving this problem, for example, JP-in No. 62-155433 mixing coal and water pasty fluid (hereinafter, C oal- W ater P aste;
A wet supply method is disclosed in which the CWP is pumped by a pump and supplied from a spray nozzle into a fluidized bed furnace.

FIG. 20 shows a fuel production / supply system for supplying CWP to a pressurized fluidized bed furnace. Fuel coal is supplied from the raw coal bunker 1 to the coarse crusher 3 by the coal feeder 2, and the coarsely crushed coal is sent to the relay hopper 4. A part of the coarsely pulverized coal is sent to a wet tube mill 5 and pulverized together with water sent from a tube mill water pump 10 to produce a pulverized coal slurry. The produced pulverized coal slurry is temporarily stored in the slurry tank 6. Coal from relay hopper 4,
The pulverized coal slurry from the slurry tank 6 and water from the water tank 7 are supplied to the kneader 13 and kneaded to produce CWP. The manufactured CWP is stored in a CWP tank 14, is pressure-fed to a CWP transport pipe 19 by a piston pump 15, and is supplied to a pressurized fluidized bed (not shown) through a CWP nozzle 21.

A piston pump 15 for supplying CWP to the pressurized fluidized bed is driven by the hydraulic pressure of a hydraulic device 17 for the piston pump, and CWP is supplied from the CWP tank 14 to the suction port 1.
6 and is sent to the piston pump 15 and sent to the CWP transport pipe 19 by pressure. Suction port 1 of piston pump 15
6, water can be injected by the water injection pump 12 and the injection pipe 22, and pulverized coal slurry can also be injected from the injection slurry pump 9 and the injection pipe 22. The hydraulic device 17 for the piston pump has a hydraulic gauge 18 for detecting the hydraulic pressure of the piston pump 15. A pressure gauge 20 is provided in the CWP transport pipe 19, and the CWP transport pipe 1 during CWP pressure feed is provided.
9 is detected.

The amount of water supplied is set so that the sum of the water content of the raw coal, the water content of the pulverized coal slurry produced by the wet tube mill 5 and the guess supplied by the water pump 11 for the kneader becomes the water content of CWP. The water content of the CWP produced by the kneading machine 13 is set to the minimum water content necessary for pumping by the piston pump 15.

In the production of CWP, it is important to minimize the amount of water added to coal in order to maintain the power generation efficiency of the boiler plant at a high level. For this reason, CWP, in which the amount of water added to coal is limited, has a high viscosity, and is extremely poor in fluidity because a chemical for dispersing coal particles is not added to reduce the production cost. In addition, CWP coal has a maximum diameter of 6-10 mm,
Since the average diameter is 1 to 2 mm and the particle size is coarse, a particle size configuration including an appropriate amount of fine particles is required in order to obtain a low moisture CWP. That is, the coal particles in CWP are characterized by being present in a wide particle size range from fine particles of several tens of microns to coarse particles of up to about 10 mm.

In order to produce a stable CWP under the above-mentioned restrictions, it is desirable to adjust the viscosity of the CWP to a range of 5 to 20 Pa · s. It has CWP viscosity of 20P
CW at the suction port of piston pump 15 above a · s
This is because clogging by P occurs and pumping becomes impossible. The viscosity of CWP mainly correlates with the concentration of coal in CWP and the particle size composition.

[0010] That is, when the coal concentration is high, the viscosity of CWP increases, and when the coal concentration is low, the CWP concentration decreases. Further, as the particle size becomes smaller, the viscosity increases. Therefore, in order to supply CWP stably, C
The most effective method is to control the concentration and viscosity of coal in WP. Therefore, the present inventors branched the CWP discharged from the kneader outlet 13 shown in FIG. 20 to measure the viscosity of the CWP 101 and the control device 102 for adjusting the viscosity of the CWP.
Patent application (Japanese Unexamined Patent Publication No. 9-14548)
No. 7, etc.).

The CWP viscosity measuring device 101 is provided at the outlet side of the kneading machine 13 and detects the CWP viscosity and supplies the water to the kneading machine 13 with the viscosity control device 102 from the water tank 7 or the pulverized coal slurry tank 6. It is configured to increase or decrease the amount of pulverized coal slurry. FIG. 21 is a structural sectional view of the CWP viscosity measuring device 101 provided on the side surface of the outlet of the kneader 13 shown in FIG. The CWP viscosity measuring device 101 includes a guide plate 105 for introducing CWP, a viscosity measuring container 106, a pin type rotor 107 for detecting viscosity, and a torque meter 110. Viscosity viscosity measurement container 1
In 06, a pin type rotor 107 for measuring the viscosity of CWP is installed at the center. Pin type rotor 107
Is connected to the torque meter 110.

At the bottom of the CWP viscosity measuring vessel 106, C
A WP transfer gate valve 111 is provided. The opening and closing operation of the CWP discharge gate valve 111 is controlled by a cylinder 112 (compressed air type or hydraulic type). The CWP discharged from the outlet of the kneader 13 is supplied to the guide plate (θ <40 degrees) 105.
From the viscosity measurement container 106 to the viscosity measurement container 106.
6 for a certain period of time. After that, the CWP is discharged by opening the gate valve 111 provided at the bottom of the viscosity measurement container 106, and the gate valve 111 is closed again to measure the CWP with the viscosity meter 1
06. This is repeated to continuously measure the viscosity of CWP.

The CWP obtained by the above wet method is pumped to the furnace by the piston pump 15 (see FIG. 20).
In order to maintain the power generation effect at a high level, it is necessary to minimize the amount of water in CWP. In addition, an agent for dispersing coal particles is not added to reduce the cost of CWP production. For this reason, CWP has a high viscosity and is extremely poor in fluidity as compared with a high-concentration coal / water slurry developed as an alternative fuel to heavy oil.

If the water content of the CWP is low, the CWP has no fluidity and cannot be pumped by the piston pump 15. For the pumping by the pump 15, the particle size distribution of CWP is, for example, that of coal having a weight average diameter in the range of 1.0 to 2.0 mm or coal having a weight average diameter of 0.03 to 0.07 mm. A prerequisite condition is that the particle size distribution has a predetermined value, such as mixing pulverized coal slurry previously mixed with water with 10 to 40% of the total coal weight. However, when the water content is gradually increased, fluidity (viscosity) appears in CWP, and the piston pump 1
5 is now possible. Since the fluidity of CWP is caused by the fine powder component of coal and water, the viscosity of CWP increases in a region where the moisture content is low by only 1/10% in a region of low moisture, and therefore the fluidity deteriorates. There is.

Since the CWP has the above-mentioned characteristics, in the production of fuel (CWP), the pump 15 is used for the CWP pumping in consideration of the variation in the water content of the raw coal and the controllability of the supply amount of each CWP component. It manufactures CWP containing several percent more water than the minimum required.

Conventionally, as shown in FIG. 20, in a CWP supply system, coal particles having a maximum diameter of about 6 mm, water and limestone as a desulfurizing agent in a furnace are mixed in a kneader 13 to obtain a CWP having a water content of about 25%. After the CWP is temporarily stored in the tank 14, the pressure is increased by a plurality of, for example, two piston pumps 15b and 15c in the example of FIG. 22, and the CWP supply conduits 31b and 31c and the CWP supply nozzles (hereinafter referred to as CWP supply nozzles). (Sometimes called a nozzle or CWP nozzle) 21
b, furnace 34 contained in pressurized container 33 through 21c
And sprayed, dispersed and burned on a fluidized bed 35 in a furnace 34. Heat transfer tube 36 in furnace 34 is heated, and steam is generated from water in the tube.

When the supply of CWP to the furnace 34 is stopped, the flow path is connected to the conduit 3 by the switching valves 37b and 37c.
The CWP is returned to the tank 14 by switching to 8b and 38c.

FIG. 22 shows a pressurized container 33, a furnace 34, a heat transfer tube 36 and a CWP supply nozzle 21 of a fluidized-bed boiler.
b and 21c are shown in plan view, but have a cross section of FIG. 22 and have a pressurized container 33, a furnace 34, a heat transfer tube 36 and a CWP.
FIG. 23 shows an arrangement relationship of the supply nozzles 21. FIG.
In 3, the furnace 34 is filled with a fluid medium (sometimes referred to as BM), fluidized by combustion air supplied from below the furnace 34 through the air distribution plate 41, and a fluidized bed 35 is formed. . The heat transfer tubes 3 in the fluidized bed 35
6 are arranged and generate steam to be supplied to a steam turbine (not shown). A dust removing device (not shown) for removing fly ash is installed at the outlet of the furnace 33, and after the dust is removed, the combustion gas is supplied to a gas turbine (not shown).

FIG. 24 shows the appearance of the CWP supply nozzle 21. The nozzle 21 is inserted into an outer cylinder 42 connected to the furnace wall 34a and the pressure vessel wall 33a, and is fixed by a flange 43. An expansion 44 for absorbing thermal expansion of the outer cylinder 42 is provided.

The total length of the CWP supply nozzle 21 is 4.5 m.
And the inner diameter of the CWP supply pipe 46 is about 50 mm.
And it is long and thin. The outer diameter of the multi-pipe including the passages for the cooling water and the dispersed air is about 220 mm, and as a whole it has a complicated multi-pipe structure, and the pressure vessel 33 and the furnace 34
, The weight is heavy and there are many places to be connected, so that once installed, the structure cannot be easily removed.

At the time of emergency stop of the furnace 34, CWP
It is required that the supply of the paste-like CWP into the supply nozzle 21 be stopped and held. The reason is as follows. That is, at the time of an emergency stop, the supply air required for the flow of the CWP is instantaneously shut off, and the fluidization of the furnace 34 stops. In this case, the supply of CWP, which has been continuously supplied from the CWP supply nozzle 21 until then, needs to be stopped immediately. This is because if CWP is continuously supplied into the furnace 34 in which the fluidized bed 35 is not fluidized, incomplete combustion occurs in the bed, and a large mass called agglomerates is formed. Heat tube 3
This causes serious problems such as damage to the fluidized layer 6 and a decrease in the fluidity of the fluidized bed 35.

Therefore, if the CWP supply is stopped in response to the emergency stop, fuel will stay in the CWP supply nozzle 21. Since this paste fuel is manufactured together with water, the higher the temperature is near the boiling point of water, the more severe the separation of coal and water becomes, and the more unstable it becomes.
It is easy to solidify. According to experiments, it is said that the temperature at which the liquid can be stably transported in the pipe is 50 ° C. or less.

For this reason, even in the normal operation, the outer circumference of the CWP supply pipe 46 is covered with a cooling water pipe (not shown), and the temperature of the CWP is kept below the stable supply temperature by the effect of the cooling water until immediately before it is supplied into the furnace fluidized bed. It has a structure to keep. Here, also in the case of emergency stop of the boiler, the cooling water flows through the cooling water pipe. However, unlike the case of the normal operation, the CWP is stopped in the CWP supply nozzle 21, so the CWP supply is stopped. Radiant heat corresponding to the furnace inner layer temperature (about 800 ° C. to 900 ° C.) flows into the tube from the furnace 34 at the tip of the nozzle 21.

For this reason, even if the CWP staying in the CWP supply nozzle 21 is lower than a predetermined temperature as a whole, the CWP located at the tip of the CWP supply nozzle 21 receives the radiant heat of the furnace 34 directly. The temperature rises and solidifies. Once a part of the CWP is solidified in the pipe, it becomes difficult to supply the CWP to the furnace in the case of restart.

[0025]

In the prior art shown in FIG. 20, a viscosity measuring device 101 is provided for measuring the viscosity of CWP discharged from the kneader 13.
The problem of the viscosity measuring device 101 is that the CWP adheres to the guide plate 105 and the inner wall of the viscosity measuring container 106 as shown in FIG. The amount of CWP attached increases with the passage of time, and is dried and solidified, making it impossible to measure the viscosity. Viscosity measuring device 101
The phenomenon that CWP adheres to the above is due to the following reasons.

(1) The CWP discharged from the kneader 13 slides on the guide plate 105 and is guided into the viscosity measuring vessel 110. When the kneading machine is stopped, the amount of CWP (A) adhering on the guide plate 105 largely depends on the inclination angle θ of the guide plate 105, and the amount of CWP attached decreases as the inclination angle θ increases. . CWP adhering on guide plate 105
(A) increases with repeated operation of starting and stopping the kneading machine 13, and is dried and solidified. When a large lump of CWP (a) adheres to the guide plate 105, the guide plate 105
Above, the slip of the CWP becomes worse, and the CWP is not guided into the viscosity measurement container 106.

(2) If the filling and discharging of CWP into the rectangular (cuboid) viscosity measuring container 106 having four corners of 90 degrees are repeated for a long time, the CWP tends to adhere to the four corners of the viscosity measuring container 106. C adhering to the inner wall of the viscosity measurement container 106
The growth of WP (b) occurs from the four corners of the viscosity measurement container 106. Further, since the height of the filled CWP varies due to the change in the CWP viscosity, the CWP attached to the inner wall of the viscosity measurement container 110 is dried and solidified when the attached CWP comes into contact with air. The adhering substance (b) does not easily peel off, and if the amount of adhering increases in a long-time continuous operation, the CWP in the viscosity measuring container 106 is not discharged, and the viscosity cannot be measured.

Therefore, a first object of the present invention is to provide a viscosity measuring device capable of measuring CWP viscosity for a long time in the process of manufacturing CWP, and to perform cleaning of each part by a cleaning device to prevent adhesion of CWP. To eliminate the problem.

In consideration of the power generation efficiency of a power plant using a pressurized fluidized-bed boiler, it is necessary to reduce the water content of CWP even slightly, but in the above-mentioned conventional technology, coarsely pulverized coal and pulverized coal slurry are used. CWP produced by the kneading machine 13 with water and water cannot be measured instantaneously in fluidity or water content. Therefore, the water content of the CWP that can be pumped by the piston pump 15 even at the lower limit of the fluctuation range of the water content of CWP. It is set above. As a result, C
There is a problem that the water content of the WP becomes unnecessarily large.

Therefore, a second object of the present invention is to reduce the water content of CWP as much as possible and to reduce the amount of CWP in the CWP feed pipe.
An object of the present invention is to enable stable pumping while preventing WP from being blocked.

The CWP supplied to the pressurized fluidized bed furnace has a large coal particle size, so that coal and water are easily separated.
Is not very fluid. For this reason, conventionally, as shown in FIG. 22, the supply of CWP does not branch on the way, and one piston pump (CWP ponte) 15 and one CWP supply conduit 31 are supplied to one CWP supply nozzle 21.
Done in For example, for the CWP supply nozzle 21b, the CWP is provided with the piston pump 15b and the CWP supply conduit 31b.
Sent by

On the other hand, as the piston pumps 15b and 15c, conventionally, two-cylinder type piston pumps are used, and as shown in FIG. 26, CW generated when a single-cylinder type piston pump is used.
There is no CWP supply stop period in the P suction step,
CWP can be continuously discharged. As a result, the temperature rise at the tip of the CWP supply nozzle 21 during the CWP supply suspension period in the suction step, and the clogging of the CWP supply nozzle 21 due to the drying and solidification of the CWP due thereto are suppressed.

When the pressurized fluidized-bed boiler becomes a commercial scale and the cross-sectional area of the fluidized bed becomes large, if the number of CWP supply nozzles 21, that is, the number of coal supply points is small, the distribution of combustion in the fluidized bed 35 becomes uneven, and the furnace In the cross section, a locally oxygen-deficient region or, conversely, an oxygen-excess region occurs. As a result, the unburned portion increases in the oxygen-deficient region, the unburned char scatters into the upper space of the fluidized bed 35, and the combustion gas containing a high concentration of oxygen flows from the oxygen-excessed region into the fluidized bed. 35, the unburned char may be burned to cause a so-called stratified combustion phenomenon.

As a result, the gas temperature rises, and may exceed the allowable temperature of the components on the downstream side of the upper layer, or exceed the measured value of the gas turbine output. Therefore, it is essential to increase the number of CWP supply points, that is, the number of CWP supply nozzles 21, in order to make the distribution of coal uniform in each region in the furnace 33.

However, because the fluidity of the CWP is not good as described above, it is necessary to provide one piston pump 15 and one CWP supply conduit 31 for one CWP supply nozzle 21. There is a problem that equipment cost increases as the number increases.

As a countermeasure, it is conceivable that the CWP supply conduit 31 is branched into a plurality of parts to supply CWP from one piston pump 15 to a plurality of nozzles 21. However, as described above, the fluidity of CWP is not good. Therefore, it is difficult to adjust the flow rate by a rapid throttle mechanism.
It is difficult to distribute them evenly. The conduit 31
There is a possibility that the nozzle 21 may be blocked due to uneven flow distribution due to the branching.

A third object of the present invention is to maintain the fluidity of CWP using a small number of piston pumps while maintaining a plurality of CWPs.
That is, CWP is supplied to the WP supply nozzle 21.

In the CWP supply nozzle structure, even if measures are taken to prevent the fuel located at the nozzle tip from solidifying under operating conditions such as an emergency stop of the fluidized bed, the fuel is solidified and the boiler is restarted. There is an event that becomes impossible.

Therefore, the fourth object of the present invention is to
It is an object of the present invention to provide a cleaning device for quickly pulverizing solidified fuel and removing the solidified fuel out of the pipe when the fuel is solidified in the WP supply nozzle.

In the pressurized fluidized-bed boiler using the above-mentioned conventional wet feed system, there is a case where the combustion must be stopped urgently due to a failure of the nozzle for feeding CWP. The causes include the following items. Blockage of the ejection hole and air ejection hole of the CWP supply nozzle 21 Leakage of cooling water of the CWP supply nozzle 21 Wear and refraction of the ejection hole of the CWP supply nozzle 21 Burnout of the tip of the CWP supply nozzle 21 During operation of the fluidized bed boiler, At present it is not possible to address these issues.

Therefore, the failed CWP supply nozzle 21
It is conceivable that the operation is continued in a state in which the boiler plant is installed, that is, in a state where the operation load is reduced, or the boiler plant is stopped, the faulty part is repaired and restarted. Therefore, it is essential to ensure the reliability of the CWP supply nozzle 21. However, if the periodic inspection of the plant is performed once a year, it is very difficult to operate the CWP supply nozzle 21 without failure for one year.

Accordingly, a fifth object of the present invention is to provide a nozzle extracting device which can repair a failed portion of a nozzle or replace a new nozzle during operation without stopping the pressurized fluidized bed boiler. .

[0043]

In order to achieve the first object, the present invention (the first invention) kneads a mixture containing a solid fuel and water (hereinafter, often referred to as a representative example by CWP). A kneading machine and a viscosity measuring device for measuring the viscosity of the paste-like fuel obtained by the kneading machine, and a water injection washing device for washing the viscosity measuring device is provided in the bypass flow path of the paste-like fuel after kneading, In a method for producing a pasty fuel while continuously measuring the viscosity while producing a pasty fuel,
A method for producing a paste-like fuel and an apparatus for operating the water-washing device of the viscosity measuring device while the kneading machine is stopped and the water-washing device is operated while the kneader is operating are employed.

The viscosity measuring device is, for example, a coal / water paste producing device provided with a device for measuring the viscosity of a mixed paste of coal, limestone and water (CWP).
A guide plate for introducing CWP, a viscosity measuring container, and a water injection means for cleaning the rotor for viscosity detection attached to the WP viscosity measurement device are provided, and a water injection operation is performed in accordance with the output signal of the water injection means and the kneading machine. Means.

The water pouring operation of the water pouring and washing apparatus is performed on the guide plate, the viscosity measuring vessel and the rotor each time the kneading machine is stopped, and the viscosity measuring vessel and the rotor are periodically cleaned during the operation of the kneading machine. The water injection operation is provided with a water injection means that is performed when a CWP discharge gate valve provided at the bottom of the viscosity measurement container is open.

In the coal / water paste producing apparatus according to the present invention, the CWP from the kneader slides on the guide plate and is guided into the viscosity measuring vessel, and is provided at the center of the rotor for detecting the stirring torque. Measure the viscosity. When the kneader stops, a thin CWP is placed on the guide plate and the inner wall of the viscosity measurement container.
Adhere and dry over time to solidify. When the CWP adhered to the guide plate is solidified, the CWP supplied from the kneader becomes poor in sliding and is not guided into the viscosity measurement container.

The CWP adhered in the viscosity measuring container becomes more easily adhered when the previously adhered CWP is dried and solidified. The amount of CWP deposited increases with time and C
WP cannot be discharged, and viscosity measurement cannot be performed.
In order to prevent the CWP from drying and solidifying, the guide plate, the inside of the viscosity measurement container and the rotor may be washed. for that purpose,
A water injection nozzle is installed, and water is supplied to the water injection nozzle after an arbitrary time (for example, 5 minutes) after the kneading machine is stopped, to wash a washing location. In particular, it is important that the washing by water injection be performed before the CWP attached to the guide plate is dried and solidified.

The adhesion of CWP to the inner wall of the viscosity measuring container also occurs during the viscosity measuring operation. This is because even when the CWP in the viscosity measurement container is intermittently discharged even during the viscosity measurement of the CWP, the flow of the CWP is stopped on the opposing wall of the side wall of the viscosity measurement container on the guide plate side. In this case, the CWP easily adheres to a portion where the CWP does not flow in the viscosity measurement container.

For this reason, the inner wall of the viscosity measuring vessel is washed when CWP is intermittently discharged from the bottom of the viscosity measuring vessel at arbitrary time intervals during operation of the kneader. It should be noted that any cleaning operation is performed when the gate valve at the bottom of the viscosity measurement container is open. This is to make it possible to easily discharge the cleaning water and the removed CWP to the discharge chute.

The second object of the present invention is to provide a coal having a weight average diameter in the range of 1.0 to 2.0 mm and a weight average diameter of 0.03 to 0.07 mm which is previously mixed with water. In a fuel production / supply method for pumping coal / water paste consisting of a mixture containing coal and water containing 10 to 40% of the total coal weight by using coal as pulverized coal slurry, based on the pressure value in the coal / water paste flow path A method for producing and supplying a coal / water paste, wherein at least one of the pulverized coal slurry and water is added to the coal / water paste to adjust the viscosity or to adjust the pumping capacity (second invention). It is solved by.

In the case of using CWP as a fuel, as described in a specific example, the pressure value in the CWP flow path or the hydraulic pressure value of the piston pump is constantly monitored, and the pressure in the piping or the hydraulic pressure of the piston pump is increased to increase the pressure in the piping. Detects an increase in the pipe resistance of the CWP to be pumped, and injects water or pulverized coal slurry related to the flow of the CWP from the suction port of the piston pump before the CWP blocks in the pipe, and the CWP blocks in the pipe. Can be prevented.

The supply of fuel to the pressurized fluidized bed furnace can be achieved by using a viscosity (fluidity) of CWP and pumping it with a piston pump. The viscosity of CWP is determined by the amount of water in CWP (and the particle size and amount of pulverized coal). If the amount of water is small, the movement of pulverized coal that moves freely between coarse coals becomes poor, and CWP is blocked in the piping. . If a certain amount of water can be maintained, the pulverized coal becomes a slurry and CWP becomes fluid.

In the present invention, the amount of water (fluidity) required for the CWP pumping is evaluated by monitoring the pressure in the pipe or the hydraulic pressure of the piston pump, and the state where the pumping becomes difficult (the pressure in the pipe or the piston) is evaluated. When the oil pressure of the pump rises), water or pulverized coal slurry is injected into the suction port of the piston pump to increase the fluidity of the CWP and avoid blockage in the piping.

A third object of the present invention is to provide a pressurized fluidized-bed boiler in which a fluidized-bed furnace having a fuel supply nozzle is provided in a pressure vessel, and to feed a paste-like fuel to a two-cylinder or multi-cylinder piston type. In a method of supplying fuel to a pressurized fluidized bed boiler supplied by a pump, each one of a plurality of pistons provided in a two-cylinder or multi-cylinder piston pump corresponds to each cylinder. A third aspect of the present invention is directed to a method of supplying fuel to a pressurized fluidized bed boiler in which paste fuel is supplied to a single fuel supply nozzle.

For example, a method of supplying CWP to two CWP supply nozzles by using one two-cylinder slurry pump,
Alternatively, CWP is supplied to a plurality of CWP supply nozzles by one multi-cylinder slurry pump having two or more pistons.
Supply.

The specific method is as follows. (1) One cylinder among a plurality of piston pumps provided in a conventionally used two-cylinder or multi-cylinder slurry pump supplies CWP slurry to a corresponding one CWP supply nozzle. I do. (2) C in the CWP supply conduit at the tip of the CWP supply nozzle
By constantly injecting water into the WP, drying and solidification of the CWP during the supply stop time of the CWP in the suction step are suppressed.

According to the method of the present invention described above, one C among a plurality of pistons of one pump is used for each C.
By supplying CWP to the WP supply nozzle, the number of nozzles is doubled or more, compared to the conventional method of supplying two or multiple cylinder slurry pumps to one CWP supply nozzle. can do.

However, by supplying CWP with one cylinder, CWP may be dried and solidified in the CWP supply nozzle during the supply stop time of the CWP suction step.

According to the method of injecting water into the CWP in the CWP supply conduit according to the present invention, this problem can be solved by the fact that the CWP can be maintained at a water concentration higher than the pump dischargeable water amount at a certain water injection amount or more. This is because the temperature rise and solidification of the CWP caused by radiant heat from the fluid medium in the furnace to the end of the CWP supply nozzle at the end of the CWP supply nozzle being stopped is suppressed by the injected water, and the water that evaporates at the same time is supplemented. The effect is.

To achieve the fourth object of the present invention,
The present invention (the fourth invention) includes a pressure vessel, a fluidized bed for fluidizing a fluidized medium contained in the pressure vessel, and a fluidized bed furnace having a fuel supply nozzle for supplying fuel to the fluidized bed. A fuel supply nozzle extraction device for a pressurized fluidized bed combustion device, wherein a fuel flow medium backflow prevention plate is provided on an outer cylinder supporting the fuel supply nozzle, a gas shutoff gate type or ball type valve, and a gas purge introduction pipe. A means for driving the nozzle back and forth and a fuel supply nozzle extraction device provided with a pressure detection conduit in the outer cylinder on the outer side of the furnace from the gas shut-off valve installation portion are used.

For example, a fluid medium backflow prevention plate, a gate type or ball type valve for shutting off gas, a gas purge introduction pipe, and means for driving the nozzle back and forth are provided on an outer cylinder supporting a nozzle for supplying CWP to the furnace. A pressure detection conduit is provided in the outer cylinder before the gas shutoff valve.

CWP for supplying CWP to the fluidized bed furnace
When the supply nozzle breaks down, for example, when the CWP ejection hole is closed, the following operations and operations corresponding to the operations are performed.

A plate for preventing backflow of the fluid medium, which is provided at the tip of the outer cylinder and which is driven up and down, is provided. Fixed, the valve is configured to be driven up and down, or the fluid medium backflow prevention plate is provided with a hinged circular plate, or to drive the nozzle back and forth, the inside of the outer cylinder, The nozzle is fixed to the outside of the nozzle with a screw or a means for injecting and fixing the nozzle inside the cylinder of the compressed gas cylinder is provided.

Further, a gas purge hole is provided on the fluidized bed side of the gas shutoff valve, and means for using exhaust gas or nitrogen gas as the purge gas, or a gas shutoff valve provided with the nozzle in a nozzle support cylinder is used. A structure may be provided in which the gas shut-off valve is closed when the nozzle is extracted to the front, and a means for extracting the nozzle out of the system after confirming that the indication of the pressure gauge provided in front of the shut-off valve is zero.

The present invention operates according to the following procedure. After stopping operation of CWP pump, CWP of nozzle part
Close the shut-off valve and remove the subsequent piping. When rotating and extracting the threaded nozzle, when the nozzle passes through the fluid medium backflow prevention plate portion provided in the outer cylinder, the fluid medium backflow prevention plate descends. Further, when the nozzle passes through a gas shut-off valve portion provided on the outer cylinder, the gas shut-off valve closes. Exhaust gas or nitrogen purge gas is passed in front of the gas shut-off valve provided on the outer cylinder to prevent backflow of the fluid medium. To confirm that the gas is completely shut off by the gas shutoff valve, open the valve in the piping section to make the pressure inside the outer cylinder before the gas shutoff valve equal to the atmosphere, close it again, After confirming that there is no rise, pull the nozzle out of the system. Repair the nozzle or insert a new nozzle from the outer cylinder. The purge gas is stopped at the same time as the gas shutoff valve provided on the outer cylinder is opened, and the nozzle is set at a predetermined position.

A fifth object of the present invention is to provide a method for cleaning the inside of a nozzle pipe in a case where a nozzle for supplying a pasty fuel obtained by adding a liquid to a solid fuel to a fluidized bed furnace is clogged with the fuel. A jig provided with a means for injecting water to the solidified fuel portion at the nozzle tip and a means for scraping out the solidified fuel is inserted into the solidified fuel portion to clean the solidified fuel in the pipe. The problem is solved by a nozzle pipe cleaning method in which water is supplied from outside the pipe and discharged again together with the pulverized solidified fuel without discharging into the fluidized bed furnace.

In the in-pipe cleaning device used for cleaning the inside of the nozzle pipe, a water injection passage reaching the tip of the rotating shaft is provided in the shaft of the rotating shaft, a drill portion is provided at the tip of the rotating shaft, and an outer peripheral portion of the rotating shaft is provided. Is provided with a spiral fin.

The method for cleaning the inside of a pipe using the apparatus for cleaning a inside of a pipe according to the present invention is performed as follows. When the operation of the fluidized bed furnace is stopped, when the furnace and the furnace are housed in the pressure vessel, the pressure of the pressure vessel decreases, and when the pressure becomes atmospheric pressure, disassemble the flange portion of the fuel supply nozzle outside the pressure vessel, The inside of the nozzle tube is accessible from outside the container. The nozzle cleaning device is installed at the position of the fuel supply nozzle outside the container, and the long shaft is inserted into the inner surface of the nozzle while rotating.

At this time, in order to insert the device into the long nozzle, it is important to align the device with the nozzle.
Positioning is easy to install the device on the nozzle flange. A drill portion is provided at the end of the long shaft, and the solidified fuel portion is cut and pulverized by the rotating force of the drill portion. The pulverized solidified fuel is discharged to the outside of the container through spiral fins provided around the shaft.

Since it is preferable to supply water to make the solidified CWP easier to cut and pulverize, the inside of the rotating shaft is hollow and supplied to the tip. This supply water is supplied to the tip of the drill portion, and then discharged to the outside of the container through the spiral fin portion together with the pulverized solidified fuel. Therefore, the supply water also contributes to the smooth discharge of the solidified fuel in the nozzle to the outside.

When the length of the nozzle is long and the length of the cleaning shaft of the apparatus is insufficient, the shaft of the cleaning apparatus is appropriately connected to increase the axial length of the apparatus. Since the weight of the shaft is deposited in the nozzle via fins provided around the shaft, even if the shaft length of the device is extended, the function of the cleaning device is not affected by bending or the like.

Even if the solidified portion and the non-solidified portion are mixed in the fuel in the nozzle, the rotational torque and the feed speed of the drill portion at the tip can be appropriately set to make the nozzle. The remaining fuel can be removed to the outside to clean the inside of the nozzle.

[0073]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show a viscometer, a control device thereof, and a water injection nozzle and a control device thereof provided in a line of a CWP manufacturing apparatus according to an embodiment of the present invention. FIG. 1 shows a viscometer and its control device, a water injection nozzle and its control device provided on the line of the CWP manufacturing device shown in FIG.

CWP discharged from kneader 13 shown in FIG.
And a control device 102 for the viscometer 101, a water injection nozzle 51 (5
1a, 51b) and its control device 53 are provided. The viscometer 101 includes an inclined guide plate 105 for introducing CWP, a viscosity measuring container 106, a pin-type rotor 107, a torque measuring device 110, and a gate valve 111 for discharging CWP.

In order to clean the viscometer 101, the guide plate 1
05 and the water injection nozzle 51
a and 51b are provided. The water injection nozzle 51a is connected to the guide plate 105.
The water injection nozzle 51b is for cleaning the viscosity measuring container 106 and the shaft 107 of the pin type rotor 110. Although not shown here, the water injection nozzle 51
It is preferable that the injection holes a and 51b have a slit shape and the injection pattern has a fan shape. Washing by water injection is performed by the operation control device 56 and the gate valve 1 of the kneader 13 (FIG. 20).
11 by the output signal of the open / close control device 102
opening / closing valve 5 provided in water supply pipes 52a, 52b to a, 51b
The opening and closing control of 3a and 53b is performed.

FIG. 2 shows a washing program for the viscometer 101. The guide plate 105 is washed when the gate valve 111 is opened after an arbitrary time after the operation of the kneading machine 13 is stopped. . The viscosity measurement container 106 is configured to be washed when the kneader 13 is stopped and at an arbitrary time interval during the operation of the kneader 13 when the gate valve 111 is open.

For measuring the CWP viscosity, the CWP discharged from the kneader 13 is branched by the guide plate 105 and
6 and measure the torque value with the pin type rotor 110,
It is performed in terms of viscosity. When the viscosity measurement of the CWP is completed, the gate valve 111 at the bottom of the viscosity measurement container 106 is opened to discharge the CWP. This operation is repeated to measure the viscosity of CWP. When the viscosity measurement is performed for a long time, the CWP adheres to the guide plate 105 and the inner wall of the viscosity measurement container 106. In particular, when the CWP is discharged from the viscosity measurement container 106 during the stoppage of the operation of the kneader 13 or during the operation, the inner wall of the viscosity measurement container 106 and the pin-type rotor 1
07 is caused by drying of the surface of the CWP adhered to the air.

In order to prevent the CWP from adhering to the members constituting the viscometer 101 and drying and solidifying after adhering, the water injection nozzles 51a and 51b should be connected to the guide plate 105.
And in the viscosity measuring container 106 part. The guide plate 105 is washed when the gate valve 111 is open after an arbitrary time after the operation of the kneading machine 13 is stopped. Viscosity measurement container 106
Is performed at an arbitrary time interval when the kneader 13 is stopped and during operation when the gate valve 111 is open.

By performing the washing operation according to the above procedure, the guide plate 105, the pin type rotor 107 and the viscosity measuring vessel 1
No CWP adheres to the inner wall portion of No. 06. The washed water is mixed into the CWP, and the water content slightly increases. An increase in the amount of water may deteriorate the properties of CWP. In order to improve the cleaning effect, an operation is performed in which the injection pressure of the cleaning water is increased (for example, 5 kg / cm ² g), the injection time is shortened (for example, 2 seconds), and the amount of water mixed into the CWP is reduced as much as possible. It is desirable.

As described above, in order to accurately measure the CWP viscosity after CWP production online, the viscosity measuring device 1 is used.
By installing a cleaning device that removes CWP attached to 01, stable measurement of CWP can be performed for a long time, and control of viscosity adjustment can be performed accurately and efficiently.

FIG. 3 shows a system of a CWP production / supply device for supplying CWP to a pressurized fluidized bed. The same devices as those shown in the system diagram of the CWP manufacturing / supplying device in FIG. 20 are denoted by the same reference numerals. That is, raw coal bunker 1, coal feeder 2, coarse crusher 3, relay hopper 4, wet tube mill 5, slurry tank 6, water tank 7, kneader slurry pump 8, injection slurry pump 9, tube mill water Pump 10, kneading machine infusion pump 11, infusion water pump 12,
Kneader 13, CWP tank 14, piston pump 15,
It comprises a suction port 16, a piston pump hydraulic device 17, a hydraulic gauge 18, a CWP supply nozzle 21, an injection pipe 22, and the like.

In the CWP manufacturing / supplying apparatus having the above configuration, the relay hopper 4 supplies coal and the slurry tank 6
And pulverized coal slurry, and water from the water tank 7 are supplied to the kneader 13 and the kneader 13 is used to knead the raw materials to produce CWP. The manufactured CWP is temporarily stored in the CWP tank 14,
The pressure is fed to the CWP transport pipe 19 by the piston pump 15 and supplied to the pressurized fluidized bed furnace 34 (not shown) (see FIG. 4) through the CWP supply nozzle 21.

The piston pump 15 that supplies CWP to the furnace 34 is driven by the hydraulic pressure of the piston pump hydraulic device 17, and the CWP is supplied from the CWP tank 14 to the suction port 16.
To the piston pump 15 and pressure fed to the CWP transport pipe 19. Suction port 1 of piston pump 15
6, water can be injected by the water injection pump 12 and the injection pipe 22, and pulverized coal slurry can also be injected from the injection slurry pump 9 and the injection pipe 22. The hydraulic device 17 for the piston pump has a hydraulic gauge 18 for detecting the hydraulic pressure of the piston pump 15. A pressure gauge 20 is provided in the CWP transport pipe 19, and the CWP transport pipe 1 during CWP pressure feed is provided.
9 is detected.

Here, the slurry pump 9 for injection from the pulverized coal slurry tank 6, the water pump 12 for water injection in the water tank 7, and the oil pressure gauge 18 of the hydraulic device 17 for piston pump are CWP.
A control device 61 for controlling the respective flow rates according to the degree of blockage of the CWP inside the pressure gauge 20 of the transport pipe 19 is provided.

The amount of water supplied is set so that the sum of the water content of the raw coal, the water content of the pulverized coal slurry produced by the wet tube mill 5 and the guess supplied by the water pump 11 for the kneader becomes the water content of CWP. The water content of the CWP produced by the kneading machine 13 is set to the minimum water content necessary for pumping by the piston pump 15. When the water content of the CWP does not fluctuate, the resistance in the CWP transport pipe 19 is constant and the pressure gauge 20
And the indicated value of the oil pressure gauge 18 are also constant.

The water content of the raw coal is reduced,
When the supply amount to the fluid fluctuates and the water content of the produced CWP decreases, the fluidity of the slurry that moves freely in the CWP deteriorates, and as a result, the piston pump 15 and the CWP transport pipe 1
The fluidity of the CWP in 9 deteriorates, and the indicated value of the pressure gauge 20 or the oil pressure gauge 18 increases. The water pump 12 for water injection is started before the pressure of the CWP becomes a closing pressure in the pipe 19 or the like, and water is injected into the suction port 16 of the piston pump 15.
Since the water content increases, the CWP sucked into the piston pump 15 has an improved fluidity in the form of a fine powder slurry, and the resistance in the pipe 19 and the like decreases.

As described above, the pressure in the CWP transport pipe 19 is monitored by the pressure gauge 20 and the oil pressure of the piston pump 15 is monitored by the hydraulic gauge 18, whereby the CWP transport pipe 1 is monitored.
9 to monitor the flow condition, the pressure gauge 20 or the oil pressure gauge 18
The clogging in the CWP transport pipe 19 due to the CWP is detected in advance based on the rising state of the indicated value. If it is detected in advance, water is injected from the water tank 7 into the suction port 16 of the piston pump 15 to improve fluidization of the CWP and avoid blockage. Even if pulverized coal slurry of the slurry tank 6 is injected instead of the water injected into the suction port 16, the fluidization of the CWP can be improved, and the blockage of the pipe 19 and the like can be avoided.

FIG. 4 is a flow chart when the present invention (third invention) is applied to a pressurized fluidized bed boiler, and FIG.
The same parts as those of the conventional example are denoted by the same reference numerals, and the description of the same flow will be omitted.

As shown in FIG. 4, a plurality of CWPs are stored in the CWP tank 14, for example, in FIG.
This is a case where the cylindrical piston pumps 15b and 15c are provided, and the two pistons of the pump 15b
WP supply conduits 31a, 31b and CWP supply nozzle 21
a, 21b, also from two pistons of the pump 15c, respectively, CWP supply conduits 31c, 31d and C
The fluid is supplied to the fluidized bed 35 in the furnace 34 through the WP supply nozzles 21c and 21d. Thereby, four nozzles 21
CW with two pumps 15b and 15c for a to 21d
P can be supplied. When stopping the supply of CWP to the fluidized bed 34, the switching valves 37a, 37b, 3
7c and 37d are connected to conduits 38a, 38b and 3 respectively.
Switch to 8c and 38d and return to tank 14.

Next, an example of the structure of the CWP supply nozzle 21 of the present invention will be described with reference to the drawings. FIG. 5 shows a CWP supply nozzle 21 applied to the present invention in which water is injected into the CWP in the CWP supply conduit 31.

The CWP supply nozzle 21 has a CWP from the center.
The supply pipe 46, the cooling water pipe 47 having a reciprocating water channel, and the CWP dispersed air pipe 48 are constituted by concentric pipes in this order. FIG.
Is characterized in that a water injection conduit 55 is provided, a leading end 55a of the nozzle 21 is opened in a CWP supply pipe 46 through an annular cooling water supply pipe 47, and a CWP in the CWP supply pipe 46 is provided. It is made to pour water. The vaporization of the water injection is prevented by passing the water injection conduit 55 through the cooling water pipe 47.

The cooling water pipe 47 flows through the cooling water,
The wall temperature of the P supply pipe 46 is 60 ° C., preferably 50 ° C.
The following is held to prevent evaporation of water in CWP. The dispersing air pipe 48 is provided with a CW supplied through a CWP supply pipe 46.
P is a conduit of high-pressure jet air for jetting P into the fluidized bed. The high-pressure air is jetted from the dispersed air jet slit 48a to the CWP supply pipe 46 to collide with the CWP coming out of the CWP supply pipe 46, and the fluid flows. The fluidized bed 35 in the bed furnace 34 is sprayed and supplied.

In the above structure, the CWP is sent through the CWP supply pipe 46, and the cooling water is sent through the cooling water pipe 47, returns from the tip of the nozzle 21, and is discharged. Dispersed air is ejected from the dispersed air ejection slit 48a to the CWP supply pipe 46, and the CWP is dispersed by the dispersed air into the fluidized bed 34.
Is spouted and supplied. The injection water is supplied to the CWP supply pipe 46 from an end 55a through an injection water conduit 55.

As described above, one piston 15 of the two-cylinder piston pump 15 passes through one CWP supply pipe 46 and one CWP supply nozzle 21 to remove C from the piston.
When supplying WP, CWP is intermittently supplied as shown in FIG. That is, in the CWP suction step, CWP temporarily stays in the CWP supply pipe 46,
The stagnant CWP is evaporated and dried and solidified by the heat entering from the fluidized bed 34. CWP shown in FIG.
According to the supply nozzle 21, since the CWP in the stopped state in the CWP supply pipe 46 is injected from the injection pipe 55, it does not dry and solidify.

FIG. 6 shows the relationship between the water injection amount of the water injection type nozzle 21 shown in FIG. 5 used in the present invention and the pump discharge pressure.
CWP supply nozzle 2 having a pipe end diameter of 27 ° of CWP supply pipe 46
1, the wall temperature of the CWP supply conduit 31 was set to 50 ° C.
, The combustion temperature of the fluidized-bed furnace 34 is 860 ° C., the furnace pressure is 0.9 MPa, and the CWP supply amount is about 600 kg / h.
(Time average value about 300 kg / h).

It was confirmed that the CWP pressure at the pump outlet did not increase at a water injection rate of 0.10 kg / h or more, that is, discharge of CWP and supply to the furnace were possible without closing the nozzle tip. Water injection volume is 0.03k
At g / h, a slight increase in the CWP pressure at the pump outlet was observed, but this did not hinder CWP discharge and supply to the furnace 34. These are C generated by radiant heat from the fluid medium in the furnace to the remaining CWP end at the nozzle tip.
This is due to the fact that the temperature rise of the WP is suppressed by the water injected from the conduit 55, and the water that evaporates at the same time is supplemented.

[0097] The amount of water supplied to the CWP supply nozzle 21 is approximately 300 kg per hour, as described above.
/ H is 0.10 kg / h or more and 0.0
This is a very small amount of 3% or more, and the effect on the combustion rate in the furnace 34 and the efficiency of the power plant is negligible.

On the other hand, the CWP is intermittently supplied to the furnace 34 as fuel.
By doubling the number of CWPs and adjusting the suspension periods of the CWP supply by the adjacent CWP supply nozzles 21 so as not to overlap, no increase in the unburned portion and the above-layer combustion phenomenon did not occur. The interval between the suction and discharge steps by the piston pump 15 was varied depending on the supply load of CWP, but was 0.5 to 3 minutes.

Further, by combining the water injection nozzle 21 and the multi-cylinder piston pump 15 having two or more pistons, the slurry can be supplied from one pump 15 to two or more slurry supply nozzles. .

FIG. 7 shows an example of an apparatus suitable for carrying out the present invention (fifth invention). The CWP supply nozzle 21 for supplying CWP into the fluidized bed furnace 34 includes a furnace wall 34 a and a pressure vessel wall 3.
3a is set in a predetermined position by being inserted into an outer cylinder 42 for connection. The outer cylinder 42 includes an expansion 44, a fluid medium backflow prevention plate 60, a gas shutoff valve 61,
It comprises a purge gas introduction pipe 62, a pressure detection conduit 64, a screw 65 for moving the CWP supply nozzle 21 forward and backward, and a cooling pipe 66 using cooling water.

The fluid medium backflow prevention plate 60 is installed on the furnace 34 side from the gas shutoff valve 61, and the vertical drive unit is a dedicated compressed gas cylinder 67 of the fluid medium backflow prevention plate 60 or as shown in FIG. The fluid medium backflow prevention plate 60 is fixed to the gas shutoff valve 61 by welding or bolts.

The gas shut-off valve 61 is of a gate type or a ball type, and has a mechanism in which vertical and rotational driving is performed by a compressed gas type cylinder 69. The purge gas introduction pipe 70 has a plurality of ejection holes 71 provided below the gas shutoff valve 61 on the furnace 34 side. Since the outer cylinder 42 is installed in an atmosphere of 350 ° C., an expansion 44 is installed in consideration of thermal expansion. The pressure detection conduit 64 is installed outside the gas shut-off valve 61, and the conduit 64
Is the pressure detector 72 and the valve 7 outside the pressure vessel wall 33a.
3 is installed. The mechanism for advancing and retreating the nozzle 21 has a structure in which screws 65 are provided inside the outer cylinder 42 and outside the nozzle 21 and the nozzle 21 is rotated and extracted. A water cooling pipe 66 is provided on the outer cylinder 42 on the outside.

In the case where CWP is supplied to the pressurized fluidized bed furnace 34, if a failure occurs in the CWP supply nozzle 21, the following operation is performed. First, the operation of the piston pump 15 is stopped, a valve 74 in front of the CWP supply nozzle 21 is closed, and a part of the pipe is removed to extract the nozzle 21 out of the system. After ejecting the purge gas 62 near the gas shut-off valve 61 provided in the outer cylinder 42 and then rotating the nozzle 21 to extract it out of the system, when the nozzle 21 passes through the fluid medium backflow prevention plate 60, the fluid medium The backflow prevention plate 60 is lowered.

Further, when the nozzle 21 is pulled out of the system,
When the nozzle 21 passes through the gas shutoff valve 61, the gas shutoff valve 61 is closed. In order to confirm the sealing performance of the gas shut-off valve 61, the valve 73 of the pressure detection conduit 64 in the outer cylinder 42 is opened, and after the pressure in the outer cylinder 42 is set to the atmospheric pressure, the valve 73 is closed and the pressure detector 72 is used. Check pressure. After completely removing the nozzle 21 from the system, a blind flange is attached to the flange 75 of the outer cylinder 42. The fluid medium that has flowed back to the tip of the outer cylinder 42 due to the exhaust gas or the nitrogen gas from the purge gas ejection holes 71 provided near the gas shutoff valve 61 is returned into the furnace 34.

The repaired nozzle 21 or a new nozzle is inserted into the outer cylinder 42 by rotation, and the gas shutoff valve 61 is inserted.
Open in front of the plate, and further a plate 60 for preventing the fluid medium from flowing backward.
Is raised and inserted to a predetermined position to supply CWP. The purge gas 62 is stopped.

Another embodiment will be described with reference to FIGS. In the example shown in FIG. 8, the plate 60 for preventing the backflow of the fluid medium shown in FIG. 7 is fixed to the gate portion of the gas shutoff valve 61, so that the plate 60 for the backflow prevention of the fluid medium is lowered together with the operation of closing the gas shutoff valve 61. It has become.

FIG. 9 is a cross-sectional view of the hinged flow medium backflow prevention plate 76. The hinged flow medium backflow prevention urate 76 falls naturally when the nozzle 21 is pulled out of the system, and the outside of the plate is removed. The cylinder 42 is closed to prevent backflow of the fluid medium. Further, the nozzle 21 is connected to a fluidized bed furnace 34.
When the nozzle 21 comes into contact with the fluid medium backflow prevention plate 76 by being inserted into the side, the nozzle 21 is pushed upward.
In FIG. 10, the driving unit for moving the nozzle 21 forward and backward has a hollow cylinder 79 of the compressed gas cylinder 78, and the nozzle 21 is installed in the hollow part and fixed with a flange 80.
The compressed gas uses compressed nitrogen or air.

In this way, the failed nozzle 21 can be extracted during the operation of the boiler, repairs and replacement of new nozzles can be easily performed without lowering the load of the pressurized fluidized bed boiler and stopping the operation, and the long-term operation can be continued. You can do it.

FIGS. 11 to 19 show an embodiment of the structure of the nozzle cleaning device according to the present invention (fifth invention). 11 and 12 are a plan view and a side view of the entire structure of the nozzle cleaning device. Cleaning shaft 80 for cleaning the inside of CWP nozzle 21
Are supported inside the drive device 81 and by a shaft support 84. The cleaning shaft 80 has a double-pipe structure, in which the supply water 86 passes through the inside of the water injection pipe 85 (FIG. 15) and is discharged between the water injection pipe 85 and the outer cylinder 87 (FIG. 15). Cleaning water passes. The supply water 86 is supplied from a hose 88 and a union joint 89, and the amount of water supply is adjusted by a water supply source valve 90. Further, the feed water 86 is provided with a swivel joint 92 for preventing the rotation of the shaft 80 from being transmitted to the hose 88 side.
Then, a water injection pipe 85 in the cleaning shaft 80 via the coupler 93.
(FIG. 15).

The CWP and cleaning water discharged between the water injection pipe 85 and the outer cylinder 87 are collected by the hose 120 from the CWP receiver 94. These components are supported by a support frame 98 attached to the drive 81,
The driving device 81 uses the flange mounting support 97 to
The WP supply nozzle 21 is mounted on the flange portion 99 (FIG. 17). Since the flange portion 99 is machined according to the hole axis of the CWP nozzle 21, the cleaning device can be automatically centered easily by mounting the driving device 81 on the flange portion 99. become. Cleaning shaft 8
Since the CWP and a part of the cleaning water are discharged outside the outer cylinder 87 (FIG. 15), the cleaning water is supplied from the shaft cleaning water inlet 121 of the hose 120 to clean the outer cylinder 87. Then, the water is discharged to the shaft washing water outlet 121 to prevent the inside of the driving device 81 from being contaminated.

FIG. 13 is a partial detailed view of the driving device 81, and FIG. 14 is a view taken along the line AA of FIG. The rotational force of the gear motor 122 is transmitted from the motor pulley 123 to the cleaning shaft 80 via the driving roller 124. A press roller 125 is provided to appropriately transmit the rotational force, and is appropriately adjusted by a jack nut 127 and attached. The outer surface of the outer cylinder 87 of the cleaning shaft 80 has a screw structure, and the cleaning shaft 80 is inserted into the tube of the nozzle 21 and pulled out in conjunction with the rotation by the shaft feeder 126 attached to the driving device 81.

FIG. 15 is a detailed view of the cleaning shaft 80 of the tip drill portion. The water injection hole 1 is provided in the drill portion 130 of the water injection pipe 85.
32 is provided, from which supply water 86 is injected to facilitate cleaning of the solidified CWP. Water injection pipe 85 and outer cylinder 87
The fins 134 are spirally wound and mounted between them, and serve to transport the internal CWP to the outside as the shaft 80 rotates. The outer cylinder 87 is fixed to the water injection pipe 85 with fixing pins 135.

FIG. 16 shows a cleaning shaft 136 which is connected to an appropriate extension when the length of the cleaning shaft 80 shown in FIG. 15 is insufficient. The cleaning shaft 136 is also composed of a water injection pipe 137 and an outer cylinder 138. Are provided with fins 139. The connection of the cleaning shaft 80 is performed by a set screw 140. Outer cylinder 1
38 is fixed to the water injection pipe 137 by a fixing pin 141.

FIGS. 17 to 19 show an outline of a cleaning procedure using the present cleaning apparatus. FIG. 17 shows a state in which the cleaning device is set on the CWP nozzle flange portion 99. The CWP and the cleaning water discharged from the CWP nozzle 21 are supplied to the CWP cleaning water receiving box 142 or the cleaning water receiving box 143.
Will be collected. FIG. 18 is a diagram showing a state diagram of the apparatus during cleaning. FIG. 19 is a view showing a state in which the cleaning device is removed after the cleaning of the inside of the CWP nozzle pipe, and the pipe of the CWP supply line 31 (FIG. 4) is attached and the cleaning is restored. Since the inside of the pipe is cleaned, it is possible to start the plant by supplying CWP smoothly.

Thus, even when the fuel supply nozzle 21 for supplying CWP to the fluidized bed furnace solidifies in the long and small diameter nozzle, the fuel remaining in the nozzle including the solidified fuel is removed from the system. And the inside of the nozzle can be quickly and easily cleaned. In addition, the CWP solidified in the furnace fluidized bed is not discharged to hinder operation.

[0116]

According to the present invention (first invention), by installing a cleaning device for removing CWP adhered to the viscosity measuring device, the CWP viscosity after CWP production can be accurately measured online and stable for a long time. Can be measured, CW
The control of the viscosity adjustment of P can be performed accurately and efficiently.

According to the present invention (second invention), it is possible to reduce the water content without blocking the CWP supplied to the pressurized fluidized bed in the pipe, and to improve the power generation efficiency of the power plant using the pressurized fluidized bed boiler. It has the effect of improving.

According to the present invention (third invention), in the supply of CWP to the pressurized fluidized bed combustion furnace, the number of CWP nozzles can be increased in comparison with the same number of pumps, and uniform combustion in the furnace cross-sectional area is achieved. Can be realized, the combustion rate in the bed is improved, the on-bed combustion phenomenon is suppressed, and a high-efficiency, low-pollution pressurized fluidized bed combustion boiler can be provided.

On the other hand, in comparison with the same number of CWP supply nozzles, the number of pumps can be reduced, and an economical pressurized fluidized bed combustion boiler with low equipment cost can be provided.

According to the present invention (fourth invention), a nozzle that has failed during operation can be extracted, repaired and a new nozzle can be easily replaced without reducing the load of the pressurized fluidized-bed boiler and shutting down the operation. it can.

According to the present invention (fifth invention), even when the fuel supply nozzle for supplying CWP to the fluidized-bed furnace is solidified in a long and small-diameter nozzle, the fuel is supplied to the nozzle including the solidified fuel. The remaining fuel can be removed outside the system, and the inside of the nozzle can be quickly and easily cleaned. In addition, the CWP solidified in the furnace fluidized bed is not discharged to hinder operation.

[Brief description of the drawings]

FIG. 1 is a system diagram of a cleaning device and a control device of a CWP viscosity measuring device provided in a CWP manufacturing device according to an embodiment of the present invention.

FIG. 2 is a program of a cleaning flow of a cleaning device of the CWP viscosity measuring device of FIG. 1;

FIG. 3 is a system diagram of a CWP production / supply device for supplying CWP to a pressurized fluidized bed according to an embodiment of the present invention.

FIG. 4 is a diagram showing an embodiment of a fuel supply system to a pressurized fluidized-bed boiler according to the present invention.

FIG. 5 is a view showing an embodiment of a slurry (CWP) supply nozzle used in the boiler of FIG. 4;

6 is a diagram showing a relationship between an amount of water injected into a CWP used in the boiler of FIG. 4 and a piston pump outlet pressure.

FIG. 7 shows C of the pressurized fluidized-bed boiler according to the embodiment of the present invention.
FIG. 4 is a cross-sectional view of the extraction structure of a WP supply nozzle.

FIG. 8 is a structural sectional view of a fluid-medium backflow prevention plate of the pressurized fluidized-bed boiler according to the embodiment of the present invention.

FIG. 9 is a structural cross-sectional view of a fluid-medium backflow prevention plate of the pressurized fluidized-bed boiler according to the embodiment of the present invention.

FIG. 10 is a sectional view of a cylinder-type extraction structure of a CWP supply nozzle of a pressurized fluidized-bed boiler according to an embodiment of the present invention.

FIG. 11 is an overall plan view showing a fuel supply nozzle cleaning device for a boiler according to an embodiment of the present invention.

FIG. 12 is an overall front view showing a fuel supply nozzle cleaning device for a boiler according to an embodiment of the present invention.

13 is a partial detailed view showing details of a driving device of the device shown in FIG.

FIG. 14 is a view taken along the line AA of FIG. 13;

FIG. 15 is a partial detailed view showing details of a nozzle cleaning shaft in FIG. 11;

FIG. 16 is a partial detailed view showing details of a nozzle cleaning shaft of FIG. 11;

FIG. 17 is a schematic view illustrating an operation sequence of the nozzle cleaning device of FIG. 11;

FIG. 18 is a schematic view showing an operation sequence of the nozzle cleaning device of FIG.

FIG. 19 is a schematic view illustrating an operation sequence of the nozzle cleaning device of FIG.

FIG. 20 is a system diagram of a conventional CWP manufacturing apparatus.

FIG. 21 is a cross-sectional view of the online viscosity measuring device shown in FIG.

FIG. 22 is a diagram showing a fuel supply system of a conventional pressurized fluidized bed boiler.

FIG. 23 is a view showing a longitudinal section of a general pressurized fluidized bed boiler.

FIG. 24 is a structural view of a CWP supply nozzle of a conventional pressurized fluidized bed boiler.

FIG. 25 shows a cleaning device of a CWP viscosity measuring device provided in a conventional CWP manufacturing device.

FIG. 26 is a diagram showing general CWP supply amount characteristics of a single-cylinder piston pump.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Raw coal bunker 2 Coal feeder 3 Coarse crusher 4 Relay hopper 5 Wet tube mill 6 Slurry tank 7 Water tank 8 Slurry pump for kneader 9 Slurry pump for injection 10 Water pump for tube mill 11 Water pump for kneader 12 Water pump for injection Reference Signs List 13 Kneader 14 CWP tank 15 Piston pump 16 Suction port 17 Hydraulic device for piston pump 18 Oil pressure gauge 19 CWP transport pipe 20 Pressure gauge 21 CWP supply nozzle 22 Injection pipe 23 CWP discharge flow path 31 CWP supply conduit 33 Pressurized container 34 Furnace 35 Fluidized bed 36 Heat transfer tube 37 Switching valve 38 Conduit 41 Dispersion plate 42, 87, 1
38 Outer cylinder 43 Flange 44 Expansion 46 CWP supply pipe 47 Cooling water pipe 48 Dispersion air pipe 48a Dispersion air jet slit 51a, 51b Water injection nozzle 52 Water supply pipe 53 Control unit 55 Water injection conduit 56 Kneader operation control device 60 Flow medium backflow prevention Plate 61 Gas shutoff valve 62 Purge gas 64 Pressure detection conduit 65 Screw 67 Compressed gas cylinder 69 Compressed gas cylinder 70 Purge gas introduction pipe 71 Purge gas ejection hole 72 Pressure detector 73, 74 Valve 75 Flange 76 Hinged plate for preventing backflow of flowing medium 78 Compressed gas cylinder 79, 112
Cylinder 80, 136 Cleaning shaft 81 Drive unit 84 Shaft support 85 Water injection pipe 86 Supply water 88 Hose 89 Union joint 90 Water injection valve 91 Stirrer 92 Swivel joint 93 Coupler 94 CWP receiver 97 Flange mounting support 98 Support frame 99 CWP nozzle flange 100 CWP
Pump 101 Viscometer 102 Viscosity (opening / closing) control device 105 Guide plate 106 Viscosity measuring container 107 Pin type rotor 110 Torque calculator 111 Gate valve 120 Hose 121 Shaft washing water inlet / outlet 122 Gear motor 123 Motor pulley 124 Drive roller 125 Roller 126 Shaft Feeder 127 Jack nut 130 Drill part 132 Water ejection hole 134, 139
Fin 135 Fixing pin 137 Injection pipe 140 Set screw 141 Fixing pin 142 CWP cleaning water receiving box 143 Cleaning water receiving box

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F23C 10/22 F23D 11/38 L 4H013 F23D 11/38 21/00 B 21/00 F23K 3/00 303 F23K 3/00 303 F23N 1/00 114 F23N 1/00 114 F23C 11/02 309 (72) Inventor Susumu Yoshioka 3-36 Takara-cho, Kure City, Hiroshima Pref. Babcock Hitachi Kure Research Institute, Inc. (72) Inventor Hiroshi Yuasa Hiroshima Hiroshima 6-9, Takara-cho, Kure-city, Kumamoto Prefecture Inside the Kure Factory of Babcock Hitachi Co., Ltd. (72) Inventor Yoshitaka Takahashi 6-9, Takara-cho, Kure-shi, Hiroshima Prefecture Inside the Kure Factory of Babcock Hitachi Co., Ltd. No. 6-9 Babcock Hitachi Inside the Kure Factory (72) Inventor Hidenori Makino 6-9 Takaracho, Kure City, Hiroshima Prefecture Bab Hitachi F term (reference) in Engineering Co., Ltd. (reference) AA03 AB10 BA02 BB11 CA06 CA07 CB05 DA21 4H013 DB15 DB16

Claims (16)

[Claims] 1. A kneader for kneading a mixture containing a solid fuel and water, kneader operation detecting means during and after operation of the kneader, and a flow path of the paste-like fuel after kneading by the kneader. A viscosity measuring device having a continuously openable and closable outlet for continuously measuring the viscosity of the paste fuel discharged from the kneader provided in the bypass flow path; a water injection means for washing the viscosity measuring device; A control device for operating the injection means when the operation detecting means detects that the kneading machine is stopped, and periodically operating the water injection means at predetermined intervals during the operation of the kneading machine. To produce paste fuel. 2. A kneader for kneading a mixture containing a solid fuel and water, a viscosity measuring device for measuring the viscosity of a paste-like fuel obtained by the kneading machine, and a water injection cleaning device for cleaning the viscosity measuring device. A method for producing a paste-like fuel, which is provided in a bypass flow path of the kneaded paste-like fuel and continuously measures the viscosity while producing the paste-like fuel, comprising: A method for producing a paste-like fuel, characterized in that a water injection cleaning device of a viscosity measuring device is periodically operated while a kneader is operating. 3. A coal having a weight average diameter in the range of 1.0 to 2.0 mm and a weight average diameter previously mixed with water of 0.03 to 2.0 mm.
A method for producing and supplying a coal / water paste comprising a mixture of coal and water containing 10 to 40% of the total weight of coal as pulverized coal slurry using coal having a range of 0.07 mm, comprising: Coal / water paste production, wherein at least one of the pulverized coal slurry and water is added to the coal / water paste based on the pressure value in the passage to adjust the viscosity or adjust the pumping capacity. Supply method. 4. While monitoring the pressure value or the pumping capacity in the coal / water paste flow path, if the pressure value or the pumping capacity value increases, water and / or pulverized coal slurry is injected into the coal / water paste. 4. The method for producing and supplying a coal / water paste according to claim 3, wherein: 5. A coal having a weight average diameter in the range of 1.0 to 2.0 mm and a weight average diameter previously mixed with water of 0.03 to 2.0 mm.
A pump for injecting pulverized coal slurry from a tank of pulverized coal slurry containing pulverized coal having a range of 0.07 mm, a water injection pump, and a kneading method for kneading a mixture containing at least coal and water containing the pulverized coal slurry. And pressurizing means for pressurizing coal / water paste, which is pulverized coal of 10-40% of the weight of the coal obtained by the kneader, in the coal / water paste flow path; At least one of pulverized coal slurry and water from the pulverized coal slurry tank provided in the coal / water paste flow path is injected using at least one of the pulverized coal slurry injection pump and the water injection pump. An injecting means of at least one of pulverized coal slurry and water; a pressure gauge provided in a coal / water paste flow path on the downstream side of the pressure feeding means; and Pulverized coal A pulverized coal slurry injection pump, a water injection pump, a pumping means, and a control device for controlling at least one of the hydraulic device for supplying to at least one of the injection means of the slurry and water. An apparatus for producing and supplying coal / water paste. 6. A pressurized fluidized-bed boiler in which a fluidized-bed furnace having a fuel supply nozzle is disposed in a pressure vessel is supplied with at least a coal / water paste, which is a mixture of coal and water, in a two-cylinder or multi-cylinder piston type. In a method of supplying fuel to a pressurized fluidized bed boiler supplied by a pump, each one of a plurality of pistons provided in a two-cylinder or multi-cylinder piston pump corresponds to each cylinder. A method for supplying fuel to a pressurized fluidized bed boiler, wherein coal / water paste is supplied to a single fuel supply nozzle. 7. Drying and solidifying the coal / water paste during the supply stop time of the coal / water paste in the suction step of the piston pump by constantly injecting water into the coal / water paste supplied to the tip of the fuel supply nozzle. The method for supplying fuel to a pressurized fluidized-bed boiler according to claim 6, wherein the fuel is suppressed. 8. A pressurized fluidized-bed boiler in which a fluidized-bed furnace having a fuel supply nozzle using coal / water paste, which is a mixture of coal and water, is disposed in a pressure vessel. A pressurized fluidized-bed boiler comprising a fuel supply nozzle provided with a fuel supply nozzle. 9. A pressurized fluidized bed provided with a pressure vessel, a fluidized bed for fluidizing a fluidized medium contained in the pressure vessel, and a fluidized bed furnace having a fuel supply nozzle for supplying fuel to the fluidized bed. A fuel supply nozzle extracting device for a combustion device, comprising: a fuel flow medium backflow prevention plate, a gas shutoff gate type or ball type valve, a gas purge introduction pipe, and a nozzle in front and rear of an outer cylinder supporting the fuel supply nozzle. A fuel supply nozzle extracting device, characterized in that a pressure detecting conduit is provided in the outer cylinder on the outer side of the furnace from the gas shut-off valve installation portion with respect to the means for driving the fuel supply nozzle. 10. The fluid medium backflow prevention plate is provided at the end of the outer cylinder so as to be vertically drivable, and the fluid medium backflow prevention plate is fixed to a gate plate of a compressed gas cylinder or a gas shutoff valve for the up / down drive. 10. The fuel supply nozzle extracting device according to claim 9, wherein: 11. A plate having a hinged circular shape provided on a plate for preventing backflow of a fluid medium.
The fuel supply nozzle extraction device according to claim 1. 12. A means for driving the fuel supply nozzle in the front-rear direction with respect to the furnace is fixed to the inside of the outer cylinder and the outside of the fuel supply nozzle with screws, or the fuel supply nozzle is fixed to the inside of the compressed gas cylinder. 10. The method according to claim 9, wherein
The fuel supply nozzle extraction device according to claim 1. 13. The fuel supply nozzle extraction device according to claim 9, wherein a gas purge hole is provided on the fluidized bed side of the gas shutoff valve, and exhaust gas, nitrogen gas, or air is used as the purge gas. 14. When the fuel supply nozzle is drawn out of the furnace from a gas shut-off valve provided on the nozzle support cylinder, the gas shut-off valve is closed and the pressure gauge provided before the shut-off valve has zero support. A method for extracting a fuel supply nozzle under pressure, wherein the nozzle is extracted out of the system after confirming. 15. A method for cleaning a nozzle pipe when a nozzle for supplying a paste into a fluidized-bed furnace by adding a liquid to a solid fuel into a paste is used to clean the inside of a nozzle pipe. A jig equipped with a means for injecting water to the part and a means for scraping the solidified fuel is inserted to the solidified fuel part, and water for cleaning the solidified fuel in the pipe is supplied from outside the pipe. And discharging the same together with the pulverized solidified fuel to the outside of the pipe without discharging it into the furnace. 16. A support which can be mounted on a distal end flange portion of a pipe to be cleaned, a rotary shaft, and a rotary shaft driving device, wherein a water injection passage reaching the rotary shaft distal end portion is provided in the rotary shaft. And a drill portion provided at a tip of the rotating shaft, and a spiral fin provided at an outer peripheral portion of the rotating shaft.