JPH02126983A - Method for forming sewage sludge incineration ash - Google Patents

Abstract

PURPOSE:To promote the deaeration in the press-forming and to enhance productivity by mixing formed body of sewage sludge incineration ash or further the crushed material calcined thereof by less than a half into sewage sludge calcination ash, and press-forming the mixture. CONSTITUTION:The ash Wa obtained by incinerating sewage sludge in an incinerator is transiently stored in a hopper 1, and a specified amt. of the ash is discharged by a feeder 2 onto a conveyor 3 and supplied to an ash feed hopper 4. The formed ash or the crushed material Wb having about 100-1000mu particle diameter obtained by crushing the calcined body of formed ash is also discharged by <=50wt.%, and supplied to the ash feed hopper 4 by a conveyor 5. The ash and the crushed material are agitated and mixed in the hopper, and a specified amt. of the mixture is supplied to a power forming press 7 by a fixed delivery feeder 6 to obtain a formed body W of the incineration ash. By this method, the formed sewage sludge incineration ash is obtained with high productivity by a simple means.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for forming sewage sludge incineration ash.

(Prior Art) Conventionally, various methods have been proposed for treating sewage sludge, but in general, the incineration ash obtained by incinerating sewage sludge in an incinerator contains binders such as calcium and lime-based Calcium is contained in 20-50% in incinerated ash and 3-10% in polymeric incinerated ash. Focusing on the fact that this calcium functions as a binder, the present applicant filed Japanese Patent Application No. 110776/1983, We proposed that the incineration ash be press-molded to form a compact that is easy to handle.

(Problems to be Solved by the Invention) However, 80% of the sewage sludge incineration ash has a particle size of approximately 30 μm, and contains a large amount of air.

Therefore, if this sewage sludge incineration ash is pressure-molded all at once using a press molding machine, an air layer (lamination) will occur in the compact, making it brittle.

Therefore, when forming sewage sludge incineration ash, we adopted a method of compressing it in stages and slowing down the compression speed. , there was a problem of extremely poor productivity.

Therefore, an object of the present invention is to provide a method for forming sewage sludge incineration ash, which can be press-formed in a short time and has good productivity.

(Means for Solving the Problems) In order to achieve the above object, the present invention involves forming sewage sludge incineration ash into a sewage sludge incineration ash by burning a formed body made of the sewage sludge bed or this formed body. 50% by weight or less of a pulverized product obtained by pulverizing the fired body is mixed, and this mixture is press-molded.

(Example) Next, an example of the present invention will be described with reference to the drawings.

First, incinerated ash Wa incinerated in a known sewage sludge incinerator is stored in an ash bar 1, cut out in a predetermined amount by a cutting machine 2, and supplied to an ash supply hopper 4 by a conveyor 3.

Further, a predetermined amount of a crushed product wb obtained by pulverizing a molded body or a sintered body of this molded body to a particle size of 100 to 1000 μm is also cut out and supplied to the ash supply hopper 4 by the conveyor 5.

The incinerated ash and pulverized material supplied into the ash supply hopper 4 are stirred and mixed here, and the mixed incinerated ash is supplied in a predetermined amount to the powder molding press 7 by the metering feeder 6, and the amount of lOOkg is / Cm' to obtain a molded body W of incinerated ash.

Note that, depending on the case, the molded body W may be further fired to form a fired body.

According to experiments, the relationship between the mixing ratio of the pulverized material to the incinerated ash and the time required for compression was as shown in the table below.

That is, as shown in FIG. 2, the larger the amount of pulverized material mixed, the better the molded product can be obtained in a shorter time. The reason why the a content of the pulverized material is set to 50% by weight or less is because if the mixing ratio is set to 50% by weight or more, when forming the incinerated ash,
This is because there is no real economic efficiency.

In addition, the ○ mark in the table indicates that a good molded body was obtained.
The mark X indicates a case where an air layer (lamination) is formed in the molded product, and cracks occur from the air layer during handling, resulting in a defective product.

The pulverized product is first used by pulverizing a compact formed by molding only the incinerated ash using the powder forming press 7, and then used as a compact formed by the above-mentioned process or a sintered product obtained by firing the same. is used.

As mentioned above, the reason why a molded body with good properties can be obtained in a short time by mixing the pulverized material with the incineration ash is because the pulverized material contains almost no air, so the air is substantially encapsulated in the incineration ash. This is thought to be because the amount of air is small and air passages are formed by the pulverized material during press molding, making it easy to degas.

(Effects of the Invention) As is clear from the above explanation, according to the present invention, a molded body made of the sewage sludge bed or a pulverized product obtained by pulverizing a fired body obtained by firing this molded body is added to the sewage sludge incineration ash. 50 layers
By a simple method of mixing 1% or less and press-molding this mixture, it is possible to accelerate deaeration during compression, increase productivity, and obtain a molded body of incinerated ash of sewage sludge.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing the method for forming sewage sludge incineration ash according to the present invention, and FIG. 2 is a graph showing the relationship between the mixing ratio of the pulverized material and the forming time. 7 - powder molding press, Wa - sewage sludge incineration ash, wb - pulverized product, W - compact.

Claims (1)

[Claims] (1) Not more than 50% by weight of a molded body made of the sewage sludge ash or a pulverized product obtained by pulverizing a fired body obtained by firing the molded body is mixed in sewage sludge incineration ash, and this mixture is press-molded. A method for forming sewage sludge incineration ash.