JPH0122524B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is a device that stably supplies sticky sludge coal containing moisture to a fluidized bed combustion device, burns the sludge coal, effectively utilizes the heat of combustion of the sludge coal, and also desulfurizes the sludge coal. Regarding.

Conventionally, there have been various difficulties in removing a highly sticky material such as sludge charcoal from a hopper and supplying it to a processing device due to its stickiness.

In recent years, the import of crude oil and heavy oil as fuel has been severely restricted, and it is an important issue to reconsider coal as a fuel, especially the effective use of sludge coal recovered in wastewater treatment facilities during coal preparation. Sludge coal is made by coagulating and precipitating fine particles in coal preparation wastewater using chemicals, and dewatering the coal under pressure using a filter press.The amount recovered is about 3 to 4% of raw coal. For example, in one mine, about 200 tons are recovered per day.
In addition, its properties include a calorific value of 3000Kcal/Kg, an ash content of 58%, and a total moisture content of about 30%, based on wet coal.
It is a low-grade coal of 2200Kcal/Kg. Therefore, it is difficult to dispose of it using conventional incineration means, but the development of a fluidized bed boiler has made it possible to effectively utilize this calorific value.

The present invention provides a device that makes it easy to stably and quantitatively supply sludge coal to a fluidized bed combustion treatment device such as a fluidized bed boiler for combustion treatment without causing the sludge coal to stick to the members of the supply device. With the goal.

In summary, the present invention provides one or more powders for supplying limestone powder to a surface in contact with a series of equipment forming a sludge coal transport system and sludge coal, respectively, in a combustion treatment of sludge coal containing moisture in a fluidized bed combustion apparatus. A sludge charcoal combustion treatment device, which is provided with a sludge charcoal supply device, and a sludge charcoal quantitative feeder located at the end of the sludge charcoal transportation system and connected to the fluidized bed combustor to subdivide the sludge charcoal and supply it to the fluidized bed. It is characterized by

This invention will be explained below with reference to the drawings. The sludge charcoal is transported from the storage facility to a hopper 2a of a sludge charcoal delivery device 2 having a belt-type transporter 4 and a drum 3 with protrusions by an excavating machine 1 such as a power shovel.
is supplied to The delivered sludge charcoal is sent between the rotating drum 6 of the belt type transporter 4 and the opposing auxiliary sludge charcoal delivery rotor 5 via the belt 4a, and then supplied to an intermediate transporter 9 such as a belt conveyor. . The plate-shaped sludge charcoal 8 is supplied from the upper end of the intermediate transporter 9 to the hopper of a sludge charcoal quantitative feeder 10, which is a screw-type feeder, and passes through a rotating blade located at the end of this quantitative feeder and an extrusion hole in an extrusion plate. The sludge coal is then supplied to the fluidized bed boiler 11 (fluidized bed combustion treatment equipment) as a short rod-shaped body of sludge coal, which burns it to generate steam through the evaporation pipe.The steam is then transferred from the drum 11a to the required locations via the main steam pipe 11b. send.

In order to prevent the sludge charcoal from sticking to the members, limestone powder is supplied from the powder supply devices 7a, 7b, 7c, 7d, and 7e to the locations where the sludge charcoal comes into contact with equipment of the sludge charcoal transport system. This limestone powder combines with sulfur oxides (SOx) generated in the fluidized bed of the fluidized bed boiler to form _CaSO4 , etc., and the damper 12
a. In the exhaust gas discharged via pipe 12
List the effects of Sox removal to eliminate SOx.

FIG. 2 is a detailed sectional view of section A in FIG. 1. The powder supply device 7a has a powder passage 13, and the limestone powder 14 is fed through a rotary valve 15 located at the bottom thereof.
The powder is then supplied onto the surface of the belt 4a from a nozzle portion 16 (which may be a long slit nozzle or a combination of a plurality of single tube nozzles) serving as a powder discharge port. The tip of a pressurized air pipe 17 is located within the nozzle portion 16, and the pressurized air blown out from there allows the limestone powder to be dispersed well onto the belt surface. The rotary valve, pressurized air supply pipe, and nozzle section are collectively referred to as a valve. Also, other anti-sticking powders may be used in place of limestone powder.

The functions when supplying limestone powder when implementing this invention will be described. Sludge charcoal contains water, making it highly viscous, and when feeding limestone powder, the sludge charcoal near the contact surface between each machine pipe of the sludge charcoal transport system and the sludge charcoal is deprived of moisture. It becomes difficult to adhere to the surface of the device.

Incidentally, limestone powder is further supplied from the powder supply device 7e near the sludge charcoal quantitative feeder 10, and the limestone powder and sludge are kneaded by the screw of the sludge charcoal quantitative feeder, and the fluidized bed is formed as small rod-shaped bodies from the discharge end. It is supplied into the fluidized bed of the boiler 11. This sludge coal quantitative feeder has its delivery end connected to the empty tower section of the fluidized bed boiler 11, and has a screw for transporting the sludge, so there is no leakage of combustion gas from the empty tower section, and moisture is removed. The moisture retained in the limestone powder is supplied to the empty column.The sludge charcoal small rods turn into steam while falling and within the bed, and the small rod-like sludge is crushed by vaporization expansion, dried, and burned, resulting in a fluidized bed. It will not accumulate on the combustion air supply plate and inhibit the fluidization of the fluidized bed.

Furthermore, limestone powder combines with SOx in the gas released during sludge combustion to form CaSO ₄ and has a deflow effect. It prevents sludge charcoal from sticking to equipment, absorbs moisture, and kneads it to be contained in small rods of sludge, which is then crushed, dried, deflowed, etc., and has a significant processing effect when burning sludge charcoal. .

By carrying out this invention, sludge charcoal sticks to the surface of the belt 4a, the outer surface of the drum 3 with projections, the auxiliary sludge charcoal delivery rotor, the belt surface of the intermediate transporter 9, the inner surface of the hopper at the inlet of the sludge charcoal metering device 10, etc. This improves the effect of quantitatively supplying sludge coal to a fluidized bed boiler. Additionally, this limestone powder has a special effect in reducing SOx in boiler exhaust gas. Limestone powder is also used for safety devices in coal mines, and has the advantage of being easy to obtain and handle.

[Brief explanation of drawings]

FIG. 1 is a side view showing the arrangement of the apparatus according to the present invention, and FIG. 2 is a detailed view of section A in FIG. 1. 3...Drum with protrusions, 4...Drum type transport machine,
7a, 7b, 7c, 7d, 7e... powder supply device, 10... sludge charcoal quantitative feeder, 11... fluidized bed boiler, 14... limestone powder.

Claims (1)

[Scope of Claims] 1. In an apparatus for combustion treatment of sludge coal containing moisture in a fluidized bed combustion apparatus, one or more devices for supplying limestone powder to surfaces in contact with a series of equipment forming a sludge charcoal transport system and sludge charcoal, respectively. A powder supply device is provided, and a sludge coal quantitative feeder located at the end of the sludge charcoal transport system and which subdivides the sludge charcoal and supplies it to the fluidized bed is connected to the fluidized bed combustion device. Sludge charcoal combustion treatment equipment. 2 The powder supply device is connected to the belt surface of the belt-type transporter on the side where the belt contacts the lower end of the hopper and enters,
The sludge charcoal combustion processing apparatus according to claim 1, characterized in that the drum with projections and the auxiliary sludge charcoal delivery rotor are located near each other. 3. The sludge charcoal combustion treatment apparatus according to claim 1 or 2, characterized in that the powder supply device is provided at the inlet of the sludge charcoal quantitative feeder. 4. Any one of claims 1 to 3, characterized in that a powder supply device for limestone powder is provided with a rotary valve and a valve having a pressurized air supply pipe connected to its powder discharge port. The sludge charcoal combustion treatment device described in the above.