JPS5854627B2 - Dust treatment method in waste incineration treatment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for disposing of dust from an incinerator for wastes such as municipal waste and sludge that generate a large amount of dust when burned.

Generally, the dust generated in an incinerator is separated by a dust collector in the flue, but handling this dust is difficult due to various obstacles.

In conventional incinerators, ash is loaded onto a conveyor that transports ash from the bottom of the furnace to an ash storage tank, and then is stored in a group hopper or ash pit.

However, the water used for extinguishing the incinerated ash and sealing the furnace pressure inside the conveyor and pit is often accompanied by the ash, mixed with dust, forms a slurry, and leaks during transportation, contaminating the environment in the workplace and along the transportation route. This caused problems in terms of pollution prevention.

In addition, sometimes the dust is transported separately, but in this case it is easily blown away by wind and vibrations.To prevent this, there is a method of humidifying by spraying water, but the amount of water is 50% of the weight of the dust. This not only reduces transport efficiency but also makes post-processing difficult and requires a large amount of cost.

Furthermore, when dust is immersed in or passes through water,
The pit drainage and conveyor drainage are contaminated by fine particles, inorganic salts, organic acids, unburned carbon, metal compounds, etc. contained in the dust, making it difficult to treat the water.

In recent years, methods have been implemented in which cement, water, and dust are mixed and solidified, but this method requires many days and a large space for curing, and requires relatively expensive media, making it expensive. There is a problem with economic efficiency.

The present invention aims to eliminate these conventional drawbacks, and it is convenient to handle the dust generated during waste incineration, does not scatter during transportation or at the dumping site, and uses a wet conveyor. The object of the present invention is to provide a treatment method that can prevent ash storage from becoming muddy due to flooding and can significantly increase the degree of reuse as well as pollution-free treatment.

Another object of the present invention is to provide a processing method that can process a large amount at once without carrying out the conventional uneconomical processing, has good processing operating conditions, and can significantly improve workability at an economical cost.

The present invention deals with the collection of dust by dry dust separation equipment such as a gravity settling device, an inertial force settling device, an electrostatic settling device, etc. for dust separation installed in the flue of a waste incinerator, such as a waste heat boiler. After extracting the dust from the dust separation equipment and before transporting or storing it together with the incinerated ash, the maximum side length is 1007n7n~
In order to directly compress and mold a granular solid object of about 10U+ without adding other substances such as water or chemicals, it is passed through a crusher, sieve, quantitative feeder, and then through a compression molding machine and solidified. This is a method for processing dust discharged from the dust collector of a material incinerator.

An embodiment of the present invention will be described with reference to the drawings.
Dust separation equipment installed in the flue 3 e.g. gravity settling type,
Dust in the combustion exhaust gas is collected by an inertial force sedimentation type or electrostatic sedimentation type dust collector, and immediately after the dust is taken out from this dust collector, a solidification molding treatment device 8 is installed, and the dust is immersed in water. After taking steps to ensure that the ash does not deliquesce and will not scatter even when blown by the wind, it is placed on the incineration ash conveyor or into the dust storage tank.

For example, the diameter distribution of municipal waste incinerator flue gas dust removed by the electrostatic precipitator is shown in Table 1.

As a method of solidifying such fine particle powder as it is taken out from the dust collector without any additives or pre-treatment, a pre-kerating machine, that is, a pre-kerating machine as the solidification molding processing device 8, is used to solidify the powder at the same speed. Pockets are cut into the surface of two rolls that rotate facing each other, and when the powder is fed between these rolls, it is compressed and granulated as the rolls rotate, and the granules are continuously discharged using a granulator. Then, granules having a lens-like, almond-like or hardtack-like shape that is symmetrical with three orthogonal axes and whose dimensions are from −10 mm to 1007 Itπ are manufactured.

If this granular solid object exceeds 100 mm, it becomes extremely brittle, so it is best to mold it to a size of 100 mm or less, and if it is less than 10 mm, it is too fine, causing problems in molding and reducing workability, so it is better to avoid it.

Note that the compression molding pressure for compression used in the solidification molding processing device 8 is i, o o o ~ 5,000 kg.
It is best to use a pressure as high as 2m to compensate for the granular solid objects that are manufactured at this high pressure, where the solidification between particles is strong. It is easy to create an object that has enough strength to not break even if it is dropped naturally, and has a degree of consolidation that does not easily collapse even if it is submerged in water.

In the illustrated example, the combustion gas generated from the incinerator 1 is humidified and cooled in the gas cooling chamber 2, which serves as an attenuation chamber, and then flows into the dust settling and separation equipment 3. The dust separated in the dust settling and separation equipment 3 is A crusher 4 crushes coarse lumps, etc., and a sieve 5 separates brick pieces and iron pieces onto a sieve and drops them into an incineration residue storage pit 6, and only the powder dust passes through a metering feeder 7 to a predetermined amount. It is supplied to the solidification molding processing device 8 of the briquetting machine.

The dust particles formed and solidified by the device 8 are placed on a conveyor 9 that transports the incinerated ash to the pit 6, or are directly thrown into the pit 6.

The order of the crusher 4 and the sieve machine 5 may be reversed so that only the coarse particles on the sieve are crushed by the crusher 4.

In the figure, 10 is an ash outlet, 11 is an exhaust fan, 12 is a chimney,
13, 14, 15, and 16 are conveyors such as a belt conveyor, and are provided as necessary.

17 is a crane that travels within the pit.

The present invention collects dust generated during waste incineration processing in a dust separation facility, extracts the dust from the dust separation facility, and then collects other substances such as water and chemicals before transporting or storing the dust together with the incinerated ash. By compressing granular solid objects under high pressure and discharging them into an incineration residue storage pit without adding additives, large amounts of dust generated during incineration of municipal waste can be easily handled and transported. It can be disposed of without being scattered inside or at the dumping site, and without deteriorating the working environment, and there is no risk of it becoming muddy due to flooding on a wet conveyor or ash storage site, making post-processing difficult, and other additives such as chemicals can be disposed of. Because it is not treated by lζ, it has good operating conditions and can be disposed of economically. It also reduces the need to dispose of difficult-to-dispose wastewater, and it does not disintegrate even when immersed in water and can be blown by the wind. Because it does not scatter, it is extremely useful for protecting the surrounding environment, and can be used for treatment without causing pollution problems.It is easy to operate, suitable for large-scale treatment, and can be treated extremely efficiently, easily, and economically. There is an advantage that the operation management for treatment is also simple.

[Brief explanation of drawings]

The drawing is a system explanatory diagram showing an embodiment of the present invention. 1... Incinerator, 2... Gas cooling room, 3
...Dust sedimentation separation equipment, 4 ... Crusher 5 ... Sieve machine, 6 ... Incineration residue storage pit, 7 ... Quantitative feeder 8・
...Solidification molding processing device, 9... Conveyor.

Claims (1)

[Claims] 1. Dust generated during waste incineration processing is collected in a dust separation facility, and after the dust is extracted from the dust separation facility and before being combined with incinerated ash and transported or stored, water, chemicals, etc. A method for treating dust in waste incineration processing, which comprises compressing granular solid objects under high pressure and discharging them into an incineration residue storage pit without adding other substances. 2. The dust treatment method for waste incineration treatment according to claim 1, wherein the granular solid objects formed by compression molding of the dust are manufactured into granular solid objects having a maximum side length of 100 mm or less. 3. Dust in the waste incineration treatment according to claim 1 or 2, wherein the dust to be compressed into the granular solid object is processed by passing through at least one of a crusher, a sieve, and a quantitative feeder. Processing method. 4 When being compressed into the granular solid object, the dust is supplied between a pair of rotating rolls, pressurized between the rolls, compressed with a pressing force of 1000 to 50001 y/i in the pockets on the roll surface, and subjected to a molding and solidification treatment. Claim 2
Dust treatment method in waste incineration treatment according to item 1 or 3. 5. The dust treatment method in waste incineration treatment according to claim 4, wherein the shaped and solidified dust particles are placed on a conveyor for transporting incineration ash and mixed and discharged into an incineration residue storage pit.