JPH0422640B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology is for the effective recycling of cake from a filter press, which is added to excavated soil for backfilling when backfilling a roadbed for road construction, etc. Belongs to the technical field.

<Summary of the Summary> The invention of this application is, for example, effective for recycling cake from a filter press installed in the wastewater treatment position of a stone crushing plant when backfilling a roadbed excavated for road construction, etc. This invention relates to a processing method used, and in particular, it is a method in which cake from a filter press is added to weathered rock and stripped soil from raw stone piles generated in a crushing plant, and a soil stabilizing material such as quicklime is added to first premix it. Further, these mixtures are crushed and mixed using a crushing and mixing device, etc., sieved, the upper part of the sieve is returned to before the crushing and mixing step, the lower part of the sieve is taken out as a product, and the upper part of the sieve is This invention relates to a method for processing a cake from a filter press, in which the cake is finely crushed through a crushing device and recirculated, or taken out as a product as it is.

<Prior art> As is well known, in the construction industry such as civil engineering and architecture, the technology of crushing many natural ores and using crushed gravel and crushed stone as aggregates, etc. is widely used. We have wet treatment equipment for processes such as crushing, mixing, and sieving, and for this reason, wastewater treatment facilities such as sewage treatment are installed, and filter presses are installed to separate earth, sand, gravel, etc. It is also widely used as a pollution control measure.

As for the processing of the cake from the filter press, only a small portion is used as raw material for pottery or as a material for soil to be placed under roof tiles, and most of it is disposed of. Ta.

<Problems to be solved by the invention> However, as a matter of course, disposal has the disadvantage of increasing transportation costs, processing costs, etc., which increases the running costs of wastewater treatment facilities and increases the price of crushed stone. .

By the way, since the cake from the filter press is made of natural ore, it is most natural and rational to reuse it as a natural soil reducing material, but until now there has been no effective use of it. It was hardly targeted.

Therefore, as shown in the invention disclosed in Japanese Patent Application Laid-Open No. 57-121386, in which the applicant is partially the applicant,
In recent years, as repairs have become more frequent due to urban redevelopment and the expansion of road networks across the country, a large amount of excavated soil is generated from plumbing work, water supply and sewerage work, electrical work, etc. Excavated soil loses its road-supporting capacity due to repeated kneading during excavation work, so it is difficult to reuse it as backfill material. This is a huge economic burden for local governments, etc.
To deal with this problem, even if a soil stabilizer such as quicklime is added to the excavated soil, a large amount of the seed soil stabilizer must be used, which is not economically viable.

<Object of the invention> The object of the invention of this application is to effectively recycle the cake from the filter press of the sewage treatment facility of the crushing plant, which is not directly related to each other, based on the above-mentioned prior art, and to recycle the excavated soil of the road construction. The problem of backfilling subgrade soil is considered as a technical problem to be solved, and the reasonable potential property of natural reduction of the cake from filter press is utilized as a backfilling material for excavated road soil. We have developed an excellent filter press cake treatment method that benefits the technical field of effective material utilization in the construction industry by taking advantage of the mutually conjugate advantages of This is what we intend to provide.

<Means/effects for solving the problems> In order to solve the above-mentioned problems, the structure of the invention of this application, which is based on the above-mentioned claims, is to solve the problems described above. Add and mix soil and stripping soil at a predetermined ratio with the filter press cake of the wet treatment wastewater treatment facility of the stone crushing plant, and premix soil stabilizers such as quicklime at a predetermined ratio, and then use a crushing and mixing device. The crushed and mixed material can be effectively reused as subgrade soil for landfill using a sieving device, or the sieved portion can be fed back to the previous stage of the crushing and mixing process, and further, the sieved portion can be finely reused. By applying a crushing action, it is effectively reused as feedback or directly as roadbed material, and in this case, the weathered rock and stripped soil from the rough stone pile are mixed with the sandy soil and clay soil in the excavated soil. deemed,
In addition, the rocks contained in these materials are treated as gravel in excavated soil and aggregates in roadbed materials, so that they can function satisfactorily.
On the other hand, cake is treated as sandy soil, clay soil, and silt of excavated soil, and its characteristics are effectively utilized, and technical measures have been taken to enable it to be effectively used as backfilling material for road excavated soil. It is.

<Example> Next, an example of the invention of this application will be described in detail as follows. Incidentally, in all the embodiments, the same parts are given the same reference numerals and explained.

In the embodiment shown in FIG. 1, a cake 3 from a filter press 2 of a wastewater treatment facility is mixed with weathered rock and stripped soil 1 of a raw stone pile generated in a crushing plant (not shown).
is added at a predetermined ratio, and
For example, quicklime 6 is added as a soil stabilizer at a predetermined ratio of 3%, and then, for example,
It passes through a well-known impact type crushing and mixing device 7 to be crushed and mixed, and is sieved by a sieving device 8, and the sieved portion is fed back to the previous stage of the crushing and mixing device 7 for circulation. For the under-sieve portion, for example, product 9 can be obtained as a backfilling material for subgrade soil of minus 10 mm.

Therefore, the material from the weathered rock and stripped soil of Product 9 is the sandy soil and clay soil of the subgrade soil, and the rocks contained therein are regarded as the gravel in the backfilling material and the subgrade material.
In addition, the material in the cake 3 can be considered as sandy soil, clayey soil, or silt, and the sieving device 8 shown in FIG.
The product material at point C, which has passed through, is compared to the point B before passing through the graph in Figure 4 (the graphs A, B, C, and D are the particle sizes passing through points A, B, C, and D in Figure 3). As shown in the distribution graph), the material is fully suitable as a backfill material on the subgrade, and the experimental results also fully satisfy this requirement.

Next, in the embodiment shown in FIG. 2, the sieved portion from the sieving device 8 of the above-mentioned embodiment is fed back to the crushing and mixing device 7 via the fine crushing device 10, or
In this embodiment, the crushed product from the fine crushing device 10 is obtained as a fine-grained product 9', and the particle size distribution of the product 9' at point E, which has passed through the fine crushing device 10, is as shown in the graph of FIG. This is as shown in E, and is an embodiment in which, for example, it is possible to obtain a roadbed material or backfilling material for subgrade soil with a fine grain size of minus 20 mm or less.

The embodiment shown in FIG. 3 is an embodiment in which the product 9' of the above-mentioned two embodiments is entirely fed back to the crushing and mixing device 7, and the product 9'' at point C that has passed through the sieving device 8 is The particle size distribution is shown in graph C shown in FIG. 4, which is obtained by mixing in the crushing and mixing device 7, and furthermore, it is possible to obtain a product that is effective as subgrade soil.

It goes without saying that the embodiments of the invention of this application are not limited to the above-mentioned embodiments, and various embodiments can be adopted, such as use as a mixing aid for building materials, for example.

<Effects of the Invention> As described above, according to the invention of this application, materials from weathered rock produced in a stone crushing plant, etc. and piles of uncut raw stones can be effectively used as subgrade soil for road backfilling, etc., instead of simply being disposed of in a landfill. Not only that, the cake from the filter press of the wastewater treatment facility, which had almost no utility value, can be effectively recycled, and the cost that would have been paid for conventional disposal can be effectively used as subgrade soil, etc. The cost benefits due to this can be balanced on the positive side, and an excellent effect can be achieved in that not only the initial cost of the wastewater treatment facility but also the running cost can be greatly reduced.

For example, when used as a backfill material for subgrade soil, weathered rock and stripped soil from a filter press cake can function as sandy soil, clay soil, or silt for backfill material; Weathered rock and stripped soil from the raw stone pile can be used as sandy soil and clay soil for backfilling, and the rocks contained therein can be used as gravel in excavated soil and aggregate for roadbed materials. There is an advantage.

[Brief explanation of drawings]

The drawings are explanatory diagrams of embodiments of the invention of this application; FIG. 1 is a flow diagram of one embodiment, FIG. 2 is a flow diagram of another embodiment, and FIG. 3 is a flow diagram of another embodiment. FIG. 4 is a graph of particle size distribution in the processing line. 10...Fine crushing device.

Claims (1)

[Scope of Claims] 1. In a treatment method used for effective regeneration of cake from a filter press inserted in a wastewater treatment process, the cake is added to weathered rock and stripped soil of a raw stone pile in a crushing plant, and a soil stabilizer is added to the cake. 1. A method for processing a cake from a filter press, characterized in that a recycled product is obtained by premixing by adding and then crushing and mixing, followed by sieving. 2. In a treatment method used for effective regeneration of cake from a filter press installed in a wastewater treatment process, the above cake is added to the weathered rock and stripped soil of the raw stone pile of a crushing plant, and a soil stabilizer is also added to premix it. A method for processing a cake from a filter press, characterized in that a recycled product is obtained by crushing and mixing, followed by sieving and finely crushing the sieved portion.