WO2014041246A1

WO2014041246A1 - Method and apparatus for handling of material classified as waste, product manufactured by the method and use of the product

Info

Publication number: WO2014041246A1
Application number: PCT/FI2013/050879
Authority: WO
Inventors: Oy Fatec
Original assignee: Oy Fatec
Priority date: 2012-09-12
Filing date: 2013-09-12
Publication date: 2014-03-20
Also published as: EP2895278A1; FI20126067A; EP2895278A4; FI126025B

Abstract

The object of the invention is a method and an apparatus for the handling of material classified as waste, in which method a material classified as waste is processed for use e.g. as an additive in the manufacture of cement, concrete, asphalt and/or a grouting material and also in earthworks. A material classified as waste is sorted into different products according to their grain size and is stored and also used as different products according to their grain size, e.g. as an additive in the manufacture of cement, concrete, asphalt and/or a grouting material

Description

METHOD AND APPARATUS FOR HANDLING OF MATERIAL CLASSIFIED AS WAS E, PRODUCT MANUFACTURED BY THE METHOD AND USE OF THE PRODUCT The object of the invention is a method as defined in the preamble of claim 1 and an apparatus as defined in the preamble of claim 10 for the handling of material classified as waste, and also a product as defined in the preamble of claim 15.

The method and apparatus according to the invention, i.e. hereinafter more briefly the solution according to the invention, is extremely well suited for handling and processing various materials classified as waste, such as e.g. the fly ash produced as a by-product of coal-fired power stations, bottom ash, vulcanic material, lump slag and granular slag, and also other suitable crushable waste, such as glass, into products fit for further refining. One extremely suitable object for handling is the fly ash produced as a by-product of coal-fired power stations, which fly ash generally nowadays is taken as waste to landfill sites, but which can, according to the invention, be used when sorted into small grain sizes e.g. as an additive to cement in the manufacture of concrete, in the manufacture of asphalt, as an additive to grouting material, and also as an earthworks material.

Fly ash is already used according to prior art for the aforementioned applications, but the results have not necessarily been sufficiently good, because the fly ash has generally been used as it is, without sorting in any way, in which case e.g. concrete, in which unsorted fly ash has been used as an additive, has been improved in terms of quality only to some extent or not at all. Cements supplemented with fly ash contain, in solutions according to prior art, generally approx. 15-35% fly ash. The use of untreated fly ash is typically seasonal, the amounts used are limited and, given the strict technical limit values set, the advantage to be gained has been small.

Efforts have been made to refine fly ash also with solutions based on scrubbing technology, but these solutions are expensive and, in addition, a drying process for the fly ash must be added on.

The aim of the present invention is to eliminate the aforementioned drawbacks and to achieve an inexpensive and reliable method and apparatus for the handling of material classified as waste. In this case the aim is to increase e.g. the reuse of fly ash in the concrete industry, in asphalt construction and in earthworks and also at the same time to reduce the amount of fly ash and other industrial waste being taken to landfill sites. The method according to the invention is characterized by what is disclosed in the characterization part of claim 1. Correspondingly, the apparatus according to the invention is characterized by what is disclosed in the characterization part of claim 10, and the product according to the invention is characterized by what is disclosed in the characterization part of claim 15. Other embodiments of the invention are characterized by what is disclosed in the other claims.

One great advantage of the solution according to the invention is getting materials that would otherwise be classified as waste and handled as waste, such as e.g. fly ash, into reuse economically and extremely advantageously. In this case one advantage, among others, is a reduction in the CO₂ emissions produced in the concrete industry by the manufacture of cement, because less cement is needed for the manufacture of concrete when some of the cement is replaced with very well sorted fly ash. This does not, however, succeed so well with unsorted fly ash. Roughly estimated, approx. 100 kg of fly ash replaces approx. 30 kg of cement. Correspondingly, ground limestone powder has conventionally been used as a filler in the manufacture of asphalt. Suitably sorted fly ash from the burning of coal is, however, well suited for the fine aggregate of asphalt surfacing, because it has homogeneous granularity, good capacity for filling porosity, a suitable low water content and it is alkaline. Since fly ash is in a bound form in asphalt mix, its environmental impacts are minor. Fly ash, and particularly fly ash sorted into a suitable grain size, can replace natural extractable soil resources e.g. in highway substrates. Fly ash is well suited to different filler structures, to foundations and to sound barriers in municipal engineering and special structures e.g. in harbors and landfill sites.

According to the invention, a material- classified as waste, such as fly ash, that has been handled according to its grain size and sorted, can be called a micronized product, for which competing products are, inter alia, untreated fly ash according to prior art and silicon dioxide i.e. silica (Si0₂) . With the solution according to the invention e.g. the following advantages are obtained: The manufactured products are of homogeneous quality and technically reliable, products manufactured in this way replace more natural materials, replace more cement, the sorting precision and better technical quality of the sorted product are better, the usage amount needed in the manufacture of concrete is smaller than with conventional fly ash, in which case raw material costs, transport costs and energy costs can be reduced, the ecological footprint is smaller than with conventional fly ash, additionally a product according to the invention is certified. One advantage of the solution according to the invention is also its advantageousness and that waste handling can be comprehensively and centrally managed, such as in a waste handling plant. Another advantage also is that all the waste for handling goes for use in different products, in which case the amount of waste decreases . A further advantage is that the heavy metals in fly ash can be enriched into their own grain size class, in which case it is known in which products of which grain size class there are no heavy metals. These products can then be used freely also in the types of application sites in which products containing heavy metal may not be used. Correspondingly, the type of product according to grain size and in which it is known there are heavy metals can be used e.g. in the manufacture of asphalt and concrete, in which the fly ash is in bound form.

In the following, the invention will be described in greater detail by the aid of some embodiments and by referring to the attached simplified drawings, wherein presents a simplified diagram of the method according to the invention,

presents a sectioned, diagrammatic and simplified side view of one sorting line, according to the invention, for fly ash or corresponding waste material ,

presents a diagrammatic and simplified top view of one sorting line system, according to the invention, for fly ash or corresponding waste material,

presents, together with Figs. 5-7, a simplified diagram of a second preferred embodiment according to the invention; in Fig. 4 a side view of a feed silo that is a raw material store and also one sorting device performing grain size sorting, Fig. 5 presents a diagrammatic and simplified side view of two product silos of a sorting line according to the invention for fly ash or corresponding waste material, in which silos is a product of a different grain size class to each other, as well as the next sorting device in the sorting line after the product silos,

Fig. 6 presents a diagrammatic and simplified side view of a product silo of a sorting line according to the invention for fly ash or corresponding waste material, said product silo being for the next grain size class,

Fig. 7 presents a diagrammatic and simplified side view of a product silo of a sorting line according to the invention for fly ash or corresponding waste material, said product silo being for the finest grain size class,

Fig. 8 presents a diagrammatic and simplified sample of recently mixed fresh concrete, and

Fig. 9 presents the sample point presented with dot-and- dash lines in Fig. 8, significantly magnified and in diagrammatic form.

In the solution according to the invention fly ash and other materials classified as industrial process waste, such as bottom ash, lump slag and granular slag as well as other suitable crushable waste, such as glass and vulcanic material, are processed in such a way that they are no longer classified as waste. In the method according to the invention fly ash and/or the other aforementioned materials are sorted and classified for achieving the desired essentially precise grain size distribution. If necessary, the material is ground smaller and delivered again to the grain size sorting. In addition, for each grain size and material their correct applications are determined. The products sorted in this way, being different in their grain size, are kept each in their own tanks for future use. This process is called more shortly "micronization" and e.g. the concrete manufactured with the raw material according to the invention micro concrete.

Fig. 1 presents a simplified diagram of the method according to the invention. In it, the fly ash la that is the raw material or other material lb suited for the purpose, e.g. classified as waste, is delivered from the storage location 1 for material to the micronization process 2 according to the invention, in which process the material is classified and sorted according to material and to grain size into different-sized fractions by means of screens and/or air blowing, e.g. by means of compressed air blowing. The products 3a thus sorted are stored according to the respective material and grain size in their storage locations 3, e.g. in silos functioning as storage tanks, from where the products 3a, e.g. fly ash screened and sorted into a certain different grain size, is delivered in the desired grain size to end users 4, e.g. for the manufacture of asphalt 4a and/or concrete 4b and/or for earthworks 4c.

Fig. 2 presents a sectioned, diagrammatic and simplified side view of one sorting line 5, according to the invention, for fly ash or corresponding waste material. In this case the material to be sorted, e.g. fly ash 12, is sorted into four different grain size classes, but there could just as well be e.g. 2, 3, 5, 6 or even more grain size classes. The material to be sorted, e.g. fly ash 12, is guided along a feeder channel 11 that is a part of a conveying path first to a screening device 13 functioning as pregrading, e.g. to a mechanical jigger screen or to an air classifier, in which the overlarge particles 20 and unburnt coal are separated from the fly ash 12 and guided back e.g. to the furnace of the power plant. The apparatus comprises means for adjusting the screen 13 according to grain size, angle of slope and other desired criteria.

The material that has gone through the screen 13 drops into the first sorting hopper 6, in the top part of which is a rotating, e.g. cogwheel-like throwing device 16, the vanes 17 of which break up the dropping material and throw some of the dropping material onwards to a second sorting hopper 7. The throwing effect is boosted with a fan 14, the pressurized air flow 15 blown by which throws the smaller and lighter material particles towards the second sorting hopper 7. Only the larger and heavier particles, i.e. the material particles 12a, drop into the first sorting hopper 6 and via it into their storage tank in the direction of the arrow 19a. The apparatus comprises means for adjusting the fan 14 according to blowing pressure, blowing direction, air volume and other desired criteria. In addition, the apparatus if necessary comprises auxiliary fans e.g. on the side of the sorting line 5 in the center part of the sorting line 5. With the auxiliary fans the passage of particles that are smaller in size, i.e.. the material particles 12b-12d, into their own sorting hoppers 7-9 is boosted.

Owing to the air flow 15 of the fan 14 and due to the throwing means 16, the lighter fly ash particles always fly from above the dividing wall 10 between two consecutive sorting hoppers in the line towards the other sorting hoppers, said wall being open at its top end and adjustable in height, and of these the particles 12b that are heavier and are second largest in grain size fall into the second sorting hopper 7, from where they are conducted onwards into their own storage tank in the direction of the arrow 19b. The open top parts of the dividing walls 10 form in this phase a conveying path for the material flow.

Correspondingly, the next smallest particles 12c manage to fly along with the air flow over the next dividing wall 10 also to as far as the third sorting hopper 8, into which they drop owing to their weight and go via it onwards into their own storage tank in the direction of the arrow 19c. Once again the smallest-sized and lightest particles 12d still fly to as far as the fourth sorting hopper 9, the back wall 10a of which finally stops them and they drop into the sorting hopper 9, from where onwards into their own storage tank in the direction of the arrow 19d. With the height of the dividing walls 10 of the sorting hoppers 6-9, the amount of fly ash to be obtained in each sorting hopper 7-9, and at the same time the particle size of the material, is also adjusted. For example, the higher the dividing wall 10 between the sorting hoppers 8 and 9 is, the smaller in grain size are the fly ash particles 12d descending into the last sorting hopper 9.

The sorting line 5 further comprises a lid 18 on top of the sorting hoppers 7-9, so that foreign objects would not gain access into the sorting hoppers 7-9 and the material being sorted would not escape along with the air flow 15.

At the first end of the sorting line 5, the fan 14 in front of the first sorting hopper 6 and the direction of air flow 15 blown by it are, from the viewpoint of sorting, extremely important. The air flow 15 is directed partly from the side and from below into the downward-falling particle flow, in which case the lighter particles fly along with the air flow partly upwards and at the same time 9

towards the other sorting hoppers 7-9 of the sorting line 5 and travel along with the air flow into their sorting hopper 6-9 intended for their own size. The throwing device 16 assists the air flow 15 to break up material flow.

Fig. 3 presents a diagrammatic and simplified top view of one sorting line system 21, according to the invention, for fly ash or corresponding waste material, which system comprises a number of sorting lines 5a-5e, corresponding to the sorting line 5, that are side by side and in which there can be both the same material as each other as well as completely different material. At the start end of the sorting lines 5-5e is a reception point for waste material with the necessary devices and at the other end of the lines and at the point of each storage tank there are collection points and distribution points for a sorted product. Between each sorting line 5-5e is preferably e.g. a runway for taking a sorted product onwards for use, or piping or some other corresponding suitable distribution channel for delivering sorted products for further use. In the bottom right-hand edge of Fig. 3 is marked the route of the product 12d with the smallest grain size of line 5 from its storage silo in the bottom part of the sorting hopper 9 for. further use. For the sake of clarity, other collection points and distribution points or distribution routes are not presented in Fig. 3.

Fig. 3 presents at the bottom the sorting line 5 for fly ash presented earlier in Fig. 2, which sorting line comprises a reception point 22, with devices, for receiving fly ash 12 and conducting it e.g. along a feeder channel 11 to the sorting device 6f of the sorting line 5 and into the sorting hoppers 6-9, from which hoppers the fly ash sorted into the desired grain size is conducted into an own storage tank for each grain size or to its packing line. Beside the sorting line 5 for fly ash there could be, if necessary, also a second or a number of essentially similar sorting lines 5 for fly ash. There could just as well be only one single sorting line 5 for fly ash in the whole apparatus. In this embodiment a sorting line 5a for the bottom ash of a power station is beside the sorting line 5 for fly ash, the sorting line 5a being essentially similar in principle to the sorting line 5 for fly ash but having handling devices that differ, if necessary, from the handling devices of the sorting line 5 for fly ash. The sorting line 5a for bottom ash comprises at least a reception point 23 for bottom ash as well as a grinding unit 28, in which the bottom ash is ground to be smaller in its grain size before sorting into the sorting hoppers 6a- 9a. The sorting is carried out with an essentially similar screening and air-blowing arrangement as the sorting of fly ash . Following that, the line system can comprise e.g. a sorting line 5b for granulated slag in grain form, the sorting line 5b being essentially similar in principle to the sorting line 5a for bottom ash but .having handling devices that differ, if necessary, from the handling devices of the sorting line 5a for bottom ash. The sorting line 5b for granulated slag comprises at least a reception point 24 for slag as well as a grinding unit 28, in which the bottom ash is ground to be smaller in its grain size before sorting into the sorting hoppers 6b-9b. The sorting is carried out with e.g. an essentially similar screening and air-blowing arrangement as the sorting of fly ash.

Following that, the line system can further comprise e.g. a sorting line 5c for vulcanic materials, the sorting line 5c being essentially similar in principle to the other sorting lines of the line system but having handling devices that differ, if necessary, from the handling devices of the other sorting lines. The sorting line 5c for vulcanic materials comprises at least a reception point 25 for the material as well as a crushing unit 29, in which the vulcanic material is crushed and, if necessary, ground to be smaller in its grain size before sorting into the sorting hoppers 6c-9c. The sorting is carried out with e.g. an essentially similar screening and air-blowing arrangement as the sorting of fly ash.

The line system can also comprise e.g. a sorting line 5d for other types of waste to be crushed, such as e.g. glass and ceramic goods that are waste, the sorting line 5d being essentially similar in principle to the other sorting lines of the line system but having handling devices that differ, if necessary, from the handling devices of the other sorting lines. The sorting line 5d for waste to be crushed comprises at least a reception point 26 for the material as well as a crushing unit 29, in which the crushable waste is crushed and, if necessary, ground to be smaller in its grain size before sorting into the sorting hoppers 6d-9d. The sorting is carried out with e.g. an essentially similar screening and air-blowing arrangement as the sorting of fly ash.

Finally, the line system according to the embodiment comprise a sorting line 5e for lump slag, the sorting line 5e being essentially similar in principle to the other sorting lines of the line system but having handling devices that differ, if necessary, from the handling devices of the other sorting lines. The sorting line 5e for lump slag comprises at least a reception point 27 for the material as well as a crushing unit 29, in which the lump slag is crushed and, if necessary, ground to be smaller in its grain size before sorting into the sorting hoppers 6e- 9e. The sorting is carried out with e.g. an essentially similar screening and air-blowing arrangement as the sorting of fly ash.

The system of sorting lines can thus comprise only one sorting line 5-5e or a number of sorting lines 5-5e side by side, in each of which is a product sorted from a different input material or in which can also be products sorted from the same input materials. Also, in the line system or in one sorting line 5-5e, in each of the storage tanks supplied by the sorting hoppers 6-9e there can be a product sorted according to only one grain size or also in one line 5-5e there can be more than one storage tank, in which is essentially the same material and also material that is essentially the same grain size as each other. In this case use of the product in question is possible also if, owing to servicing or for some other reason, one storage tank were out of use.

What is essential to the solution according to the invention is that the products made by sorting from waste material are stored in their tanks sorted into products according to the essentially precisely defined grain size desired, in which case the products are easy to use in the use for which they are exactly best suited, such as e.g. as an additive to cement for the manufacture of concrete.

Table 1 presents an extract from one test result, in which fly ash was sorted with a test device of the type of the method and of the apparatus according to the invention. In it, Product 1 is essentially unsorted coarse raw material and Product 5 is the most fine-grained material of all. Four different percentage volume values are presented in the vertical columns: D10, which corresponds to 10%; D50, 3 050879

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which corresponds to 50%; D97, which corresponds to 97%; and D100, which corresponds to 100%. The decimal figures presented in the columns are the grain sizes of the material in micrometers (μηα) .

Table 1 For example, if looking at the lowermost Product 5, it is seen that in the sorting 100% of all the material has gone through the screen, the aperture size of which is 4 μιη, i.e. in the sorted product the largest grain size is 4 μιη. Generally, however, a more important criterion is considered to be a grain size with the value D97, which in most cases is sufficient instead of D100, and the product is usually evaluated with the value D50, with which the average fineness of the grain ^" size of the product is determined. From Table 1 it is seen that the average fineness D50 of Product 5 is thus 1.46 μπι and more than 10% of the product is of material having a grain size of below 1 μπι, i.e. a part of the product already belongs to the nanometer scale in terms of its grain size.

The handling and sorting of fly ash and other usable waste material into products of exactly a certain size in terms of their grain size enables the inexpensive and appropriate productive use of these products in different applications, in which the use of materials not sorted in this way could not earlier have been implemented. For example, fly ash selected according to exactly the correct grain size as an additive to cement used in concrete, among other things, improves the quality of the concrete and lowers the price of concrete and also reduces the consumption of cement.

When fly ash sorted into precisely the correct grain size is used as an additive to the cement needed in the manufacture of concrete, less fly ash can be used than in solutions according to prior art for achieving the same end result, i.e. instead of 15-35% fly ash, only 2-14% is needed in the solution according to the invention. In this case the grain size of the fly ash is e.g. as follows: D50 is between 1-8 μκι, D97 is between 2-40 μπι and D100 is between 3-80 μιη. Correspondingly D10 is between 0.5-2 μπι.

Figs. 4-7 present a simplified diagram of a second preferred embodiment according to the invention. The machines, devices and actuators presented in Figs. 4-7 can be regarded as together forming one sorting line according to the invention, e.g. applicably corresponding to the aforementioned sorting line 5, with product silos 38, 39, 47 and 48, fans 14 and sorting devices 6f, 7f, i.e. classifiers, as well as with conveying paths for the material flow of a material classified as waste, which conveying path refers to the different paths of passage of the aforementioned material flow from the furnace plant to the product silos 38, 39, 47 and 48.

In the solution according to the embodiment presented by Figs. 4-7 at the start end of the sorting line is a feed silo 30 functioning as a raw material storage, into which a coarse-grained material to be sorted, e.g. fly ash 12 or a corresponding waste material, is conducted e.g. from the furnace boiler of a power plant. At the bottom end of the feed silo 30 is a shutoff and feeder apparatus 31 for conducting the fly ash 12 onwards along its conveying path to the first sorting device 6f of the sorting line. The shutoff and feeder apparatus 31 comprises e.g. a gate valve 31a or corresponding shut-off means, which is used mainly in connection with servicing, a motor-driven box feeder 31b and a motor-driven conveyor means 31c, e.g. a screw conveyor. By means of the shutoff and feeder apparatus 31 the fly ash 12 is conducted via an injector 32 to the sorting device 6f, into which injector 32 compressed air 33 is blown e.g. with the fan 14 mentioned before or with a corresponding device. The compressed air 33 is blown inside the sorting device 6f from the bottom part of the sorting device 6f, in which case the injector 32 pulls the fly ash 12 inside the sorting device 6f and the air flow rising upwards lifts the particles with the smallest grain size towards the top part of the sorting device 6f, where the particles with the smallest grain size leave the sorting device along their conveying path as a particle flow 36a, which comprises only particles smaller than the set grain size adjusted with the adjustment means 35 of the sorting device 6f.

The grain size of the particle flow, i.e. the material flow 36a, is arranged to be adjusted alternately, e.g. in such a way that one time the maximum grain size is e.g. 40 μιτι and the second time some other, e.g. 20 μπι. In this case the heavier particles 20 that exceed the set maximum size in terms of their grain size are removed from the sorting device 6f, from the bottom of it, e.g. back into their own circulation, for incineration, to the screen or to other filters. In the solution according to Fig. 4 the material flow 20, in which there are particles e.g. larger in grain size than 40 μιη, is conducted via the diverter device 56 either to grinding, e.g. in a ball mill 57, after which the material flow 20a now reduced in its grain size, is conducted back to the sorting device 6f, or to grinding in the jet mill 58, which is adjusted in such a way that the outcoming material flow 20b is sufficiently small and homogeneous in its grain size for transferring directly into the product silo. By grinding the coarse-grained material flow 20 and by again conducting it to the sorting device 6f or after jet pulverization directly into the product silo, a more fine-grained product that is also more valuable in its price is obtained as an end result.

The sorting result is acted upon, if necessary, by blowing additional air 34 inside the sorting device 6f. In the top part of the feed silo 30 and of the product silos 38, 39, 48, 49 there is e.g. a filter 37 preventing the material in the silos from escaping into the outside air. The material brought to the sorting device 6f, e.g. fly ash 12, is thus sorted once in the sorting device 6f into two size classes; and at each time both into a size class smaller than the defined limit grain size and into a size class larger than the limit grain size. Fig. 5 presents two product silos 38 and 39 in the sorting line that are essentially similar in terms of their apparatus, into which silos in this solution the particle flow 36a that has been sorted by particle size is conducted along its conveying path from the same first sorting device 6f. There could just as well be its own sorting device 6f for both product silos 38, 39, but by suitably adjusting the functions of the sorting line one single sorting device 6f is sufficient to guarantee even capacity. In this case only the sorting device 6f is used in such a way that by adjusting the grain size of the particle flow 36a leaving the sorting device 6f, the material of larger size in terms of its grain size is sorted into the first product silo 38 and correspondingly the material of smaller size in terms of its grain size into the second product silo 39 alternately, as is already mentioned above.

When the coarser material is taken as a product, the material flow 36a coming from the sorting device 6f is conducted through the product filter 40 to the diverter device 42, such as to a screw, flap or corresponding, by means of which diverter device 42 the coarser material is guided into the first product silo 38. Correspondingly, when the finer-grained material is taken as a product, the finer-grained material flow 36a coming from the sorting device 6f is conducted through the product filter 40 by means of the diverter device 42 into the second product silo 39. A pump 41 is connected to the product filter 40 in such a way that the suction effect achieved with the pump 41 facilitates the conducting of the material flow 36a into the product silos 38, 39.

In both product silos 38, 39 at the bottom end are two material outlet points 38a and 38b as well as 39a and 39b provided with shutoff and feeder apparatuses 31 or with corresponding devices, which outlet points are e.g. narrowing downwards in a funnel-shaped manner. From the first outlet point 38a, 39a the product material 36a sorted by its grain size is loaded e.g. into a transport vehicle 43 or into a freight container 44 by means of a loading bellows 31d. Correspondingly, from the second outlet point 38b, 39b the product material 36a sorted by its grain size is conducted by means of a conveyor means 31c onwards for sorting to the next sorting device 7f in the sorting line, in which sorting device the material 36a brought into the sorting device 7f is again sorted, e.g. by means of pressurized air blowing, in essentially the same manner as on the sorting device 6f presented previously, into two size classes 36b and 36c having grain sizes of different magnitudes, of which the size class 36b is larger in its grain size and 36c is smaller in its grain size. The product material 36a is conducted from the product silos 38, 39 along their conveying path into a second sorting device 7f by means of fans 14 and via the injectors 45, 46, as has been described earlier in connection with Fig. 4 and in connection with the first sorting device 6f. Additional air 34 is also blown, if necessary, into the sorting device If.

The coarser product material 36b to be taken out from the bottom part of the sorting device 7f can be again conducted into the sorting device 7f as was done in connection with the sorting device 6f, or it can be conducted along its conveying path onwards into its own product silo, into which in this case comes product material 36b that is more homogeneous than the product material 36a in the original product silo 38 or 39, because the finest-grained part 36c has already been sorted out. For example, if the input material were product material 36a, having a grain size below 20 μιτι, in the product silo 39, after the sorting device 7f there would be finer-grained material 36c, e.g. with a grain size of less than 5 pm and larger-grained material with a grain size of between 5-20 \im.

Fig. 6 presents a product silo 47, into which the coarser- grained material flow 36b is conducted along its conveying path from the second sorting device 7f . The product silo 47 comprises an essentially similar shutoff and feeder apparatus 31 with a loading bellows 31d as in the product silos 38, 39 of Fig. 5 and the product material 36b in the product silo 47 is loaded e.g. into transport vehicles 43 or freight containers 44.

Correspondingly Fig. 7 presents a product silo 48, into which the finer-grained material flow 36c is conducted along its conveying path from the second sorting device 7f . The product silo 48 comprises an essentially similar shutoff and feeder apparatus 31 with a loading bellows 31d as in the product silo 47 of Fig. 6 and the product material 36c in the product silo 48 is loaded e.g. into freight containers 44 or large sacks 49.

If a product material with a grain size even smaller than the product material 37c is desired, a new sorting device essentially corresponding to the sorting device 6f or 7f can be added after the product silo 48, with which sorting device the smallest product material so far, e.g. the product material with a grain size of below 5 μπι, is further divided into two grain size classes, of which the coarser is as large in its maximum grain size as the product material 37c but more homogeneous and the finer is smaller in its maximum grain size than the product material 37c. Proceeding in this way, by further connecting sorting devices 7f in series into the sorting line, still smaller and smaller product materials in their maximum grain size can be obtained, right up to the nanometer scale in their grain size.

On the conveying path of the material flow the last device of the sorting line can also be the jet mill 58, mentioned in connection with Fig. 4, which jet mill is provided with an internal sorting device, in which case the product material pulverized by the grinding of the jet mill 58 is sufficiently homogeneous and small in its grain size to be directly ready product material. With the jet mill that is 879

20

in connection with the sorting line it is possible to reach a product material that is in the nanometer scale in terms of its grain size. At its simplest the sorting line according to the invention comprises at least one product silo 38, 39, 47 or 48 and at least one sorting device 6f, 7f, as well as a raw material source. Preferably the raw material source is the feed silo 30 described above, into which e.g. the fly ash 12 that is raw material is stored. In this case the coarse-grained, e.g. pregraded, fly ash 12 is guided by means of compressed air through the sorting device 6f in the manner stated above, wherein the fly ash 12 is divided by grain size into two different size classes, of which the product material with the smaller grain size is conducted into a product tank 38 or 39 for further use. Correspondingly, the material 20 of larger grain size is again conducted into the sorting process or other use as is stated above. When using sorting devices 6f, 7f, in which the material to be sorted is divided into two different-sized fractions, the solution according to the invention comprises adjustment means, by the aid of which the direction and/or strength of an upward-directed air flow brought about with a fan 14 or a corresponding actuator is/are adjusted in such a way that as a result of the sorting into two different size classes performed the size class 36a, 36c that is essentially smaller in its grain size than the predefined limit grain size is essentially approx. 20-40% of the sorted amount, suitably approx. 25-35% and preferably approx. 1/3 or approx. 30%, and the size class 20, 36b that is essentially larger in its grain size than the predefined limit grain size is essentially approx. 60- 80% of the sorted amount, suitably approx. 65-55% and preferably approx. 2/3 or approx. 70%. Correspondingly, when using a solution wherein the material to be sorted is divided directly into multiple different- sized fractions, e.g. into the four different-sized fractions described in the preceding, the solution according to the invention comprises adjustment means, by the aid of which the direction and/or strength of an obliquely upward-directed air flow brought about with a fan 14 or a corresponding actuator is/are adjusted in such a way that as a result of the sorting into different size classes performed approx. 5-15%, suitably approx. 10%, of the sorted amount is allowed to drop into the first sorting hopper 6, approx. 35-45%, suitably approx. 40%, of the sorted amount is conducted into the second sorting hopper 7, also approx. 35-45%, suitably approx. 40%, of the sorted amount is conducted into the third sorting hopper 8, and approx. 1-7%, suitably approx. 3-5%, preferably approx. 4%, of the sorted amount is conducted into the last sorting hopper 9.

In this way as a result of the sorting performed by means of a directly or obliquely upward-directed air flow brought about with a fan 14 or a corresponding actuator the desired amount of products of a predetermined grain size can be obtained in the sorting hoppers 6-9 or the product silos

38, 39, 47, 48.

By disposing sorting devices 6f, 7f and product silos 38,

39, 47 or 48 consecutively in series in the conveying path of the material flow as a sorting line, the reduction of grain size can be continued up to a particle size in the nanometer scale in terms of grain size, as has been stated above. A sorting line assembled in this way is extremely effective and flexible, and particularly in smaller scale use very inexpensive. Also, sorting lines disposed in series can also be disposed side by side, as is already mentioned above.

Apparatus solutions that are per se different do not, in fact, have a great difference from the viewpoint of the inventive concept, as long as it is borne in mind that what is essential to the solution according to the invention is that the products made by sorting from waste material are stored in their tanks or in their product silos sorted into products according to the essentially precisely defined grain size desired, in which case the products are easy to use in the use for which they are exactly best suited.

Figure 8 presents a diagrammatic and simplified sample of recently mixed fresh concrete, in which is both small stones 51 and larger stones 52 as a reinforcement in a mixture of cement gel 50, presented with diagonal lines, that is the binder agent. In addition, there can be metal reinforcements and other reinforcements in the concrete, but they are not presented in the figures. The sampling point 53, which is presented in much greater magnification in Fig. 9, is also added in Fig. 8 presented with dot-and- dash lines. The sample of concrete according to Fig. 9 is diagrammatic and simplified and it only presents how the grains 54 of fly ash sorted according to the invention are situated between cement grains 55 larger than them, condensing the structure of the cement mass functioning as a binder agent. Without fly ash grains 54 smaller in size than the cement grains 55, an unnecessary abundance of empty space, e.g. approx. 2-15%, would remain between the cement grains 55, which empty space weakens the structure. Fly ash that is smaller-grained than cement grains 55 and selected by grain size correctly for the intended use and that is used as an additive to cement thus physically increases the strength of the cement and in this way strengthens concrete manufactured from cement to which the fly ash has been added, and the concrete becomes better workable and placeable. Likewise, among other things, drying cracks decrease and frost resistance improves.

According to prior art, when manufacturing cement the fly ash is added to the cement in the ^' grinding phase of the cement. In this case, however, it is not necessarily possible to obtain fly ash of the correct size in terms of grain size with respect to the properties of the cement grade being manufactured at that particular time. According to the invention fly ash with a grain size that is of just the correct size is added to cement only in the final phase of the grinding of the cement or after it, in which case the grain size of the fly ash depends on the intended use of the cement. Thus larger-grained fly ash in terms of grain size is added to cement containing large cement grains 55 and smaller-grained fly ash in terms of grain size is added to cement containing smaller cement grains 55. In this way cement mixtures of good quality are obtained for different applications.

When manufacturing cement-based grouting materials for filling various gaps and cracks, such as concrete cracks or rock cracks, the solution according to the invention enables an extremely good end result, because the adding of fly ash used as an additive to cement or the adding of another suitable product manufactured from the aforementioned waste materials and sorted into suitable grain sizes is extremely easy according to the intended use. Often in this case fly ash that is smaller in its grain size than the cement grains 55 is added to the desired product according to the method presented by Fig. 9, said fly ash making the structure denser. The cement mixture can also be manufactured in such a way that the cement grains 55 are smaller in size than the fly ash 54, but in this case also it is essential that sorted fly ash with a known grain size is used.

According to the invention fly ash grains 54 smaller than cement grains 55 are mixed into cement suited to the manufacture of concrete to fill the empty spaces between only the cement grains 55, in this case selected fly ash that is precisely sorted by its grain size on the basis of the cement grade desired is mixed into the cement, said fly ash being only approx. 2-14% of the amount of the cement, suitably e.g. approx. 3-12% and preferably e.g. approx. 5- 10% or whatever suitable percentage whatsoever of the ranges presented above, i.e. 4, 6, 7, 8, 9, 11 or 13 percent or parts thereof. In this way the amount of fly ash to be used can thus, owing to the precise grain size sorting, be a lot smaller than the approx. 15-35% of the amount of the cement that is used according to prior art.

It is obvious to the person skilled in the art that different embodiments of the invention are not only limited to the examples described above, but that they may be varied within the scope of the claims presented below. What is essential is that an additive product, such as fly ash or other material classified as waste, sorted by grain size according to the intended use, is used, in which case the grain size of the aforementioned additive product is essentially precisely known.

It is further obvious to the person skilled in the art that a sorted additive product according to the invention can also be made with other methods and apparatuses than those presented above.

Claims

1. Method for the handling of material classified as waste, in which method a material classified as waste is processed for use as an additive either in the manufacture of cement, concrete, asphalt and/or a grouting material or also in earthworks, characterized in that the material classified as waste is sorted when dry, using as an aid at least air blowing that is directed either directly or obliquely upwards, into products of different grain size and is stored in its storage tanks as products of different grain size, and is used according to its grain size as essentially precisely defined different products as an additive either in the manufacture of cement, concrete, asphalt and/or grouting material or also in earthworks.

2. Method according to claim 1, characterized in that the material classified as waste is sorted when dry in a sorting device (6f, 7f) disposed in a sorting line on the conveying path of the material flow by means of a pressurized air flow according to its grain size into at least two different size classes, of which, the first is a size class (36a, 36c) essentially smaller in its grain size than the predefined limit grain size and the second is a size class (20, 36b) essentially larger in its grain size than the predefined limit grain size, and the product material that is of a size class (36a, 36c) essentially smaller in its grain size than the predefined limit grain size is conducted into a product silo (38, 39, 48), from where the product material is taken into other use or onwards to be sorted according to its grain size into at least two different size classes, e.g. by means of the next sorting device (7f) in the same sorting line, and after sorting is conducted into the next . product silo, continuing, if necessary, the division of the product material always into two new size classes until the smallest size class needed is achieved.

3. Method according to claim 2, characterized in that the direction and/or strength of the air flow directed upwards is adjusted in such a way that as a result of the sorting into two different size classes performed the size class (36a, 36c) that is essentially smaller in its grain size than the predefined limit grain size is essentially approx. 20-40% of the sorted amount, suitably approx. 25-35% and preferably approx. 1/3, and the size class (20, 36b) that is essentially larger in its grain size than the predefined limit grain size is essentially approx. 60-80% of the sorted amount, suitably approx. 65-55% and preferably approx. 2/3.

4. Method according to claim 1, characterized in that the material classified as waste is sorted according to its grain size by removing first the largest particles with a screening device (13) or corresponding, after which the material flow is conducted into mechanical separation, such as a rotating throwing device (16) and at the same time air is blown into the material flow with a fan (14) with a force that transports particles (12a-12d) of different sizes in terms of their grain size into sorting hoppers (6- 9) according to their size class and onwards into their own storage tanks .

5. Method according to claim 1 or 4, characterized in that air is blown obliquely upwards into the downward-falling material flow in such a way that the largest-sized particles (12a) are allowed to drop directly into the first sorting hopper (6) and particles (12b) of the next largest size fly, assisted by a throwing means (16) along with the air flow (15) into the second sorting hopper (7), and particles (12c) of the next largest size flying onwards along with the air flow drop into the third sorting hopper (8) and the smallest-sized particles (12d) drop into the last sorting hopper (9) .

6. Method according to claim 5, characterized in that the direction and/or strength of the air flow blowing obliquely upwards is adjusted in such a way that as a result of the sorting into different size classes performed approx. 5- 15%, suitably approx. 10%, of the sorted amount is allowed to drop into the first sorting hopper (6), approx. 35-45%, suitably approx. 40%, of the sorted amount is conducted into the second sorting hopper (7), also approx. 35-45%, suitably approx. 40%, of the sorted amount is conducted into the third sorting hopper (8), and approx. 1-7%, suitably approx. 3-5%, preferably approx. 4%, of the sorted amount is conducted into the last sorting hopper (9) .

7. Method according to any of the preceding claims, characterized in that different materials classified as waste, such as fly ash, bottom ash, vulcanic material, granulated slag, lump slag and crushable waste, such as glass, porcelain, et cetera, are sorted according to grain size each into its own storage tank for different products, which are used either as additives or as they are for various applications.

8. Method according to any of the preceding claims, characterized in that the material classified as waste is sorted according to grain size into different products, the grain sizes of which are e.g. one or more of the following: D10 is between 0.5-2 μπι; D50 is between 1-8 pm; D97 is between 2-40 μπ\ and D100 is between 3-80 μπ\.

9. Method according to any of the preceding claims, characterized in that fly ash is mixed as an additive into cement to be used in the manufacture of concrete, the fly ash being approx. 2-14% of the amount of cement, suitably e.g. approx. 3-12% and preferably e.g. approx. 5-10% or whatever suitable percentage whatsoever of the ranges presented above, i.e. 4, 6, 7, 8, 9, 11 or 13 percent or parts thereof.

10. Apparatus for the handling of material classified as waste, in which apparatus a material classified as waste is arranged to be processed into a product for use as an additive either in the manufacture of cement, concrete, asphalt and/or a grouting material or also in earthworks, and which apparatus comprises at least one or more sorting hoppers (6-9) or one or more product silos (38, 39, 47, 48) for a product processed from a material classified as waste and at least one conveying path for conducting a material classified as waste from one location to another as a material flow, characterized in that on the conveying path of the material flow before one or more sorting hoppers (6- 9) or before one or more product silos (38, 39, 47, 48) is a sorting device (6f ) , which is arranged to sort when dry the material flow conducted to the sorting device (6f), using as an aid an air flow (15, 33) directed from below obliquely or essentially directly upwards, according to its grain size into at least two different size classes, and in that the material classified as waste is arranged to be kept as different products sorted according to their grain size in sorting hoppers (6-9) or in product silos (38, 39, 47, 48) for use as different products according to their grain size, preferably as an additive either in the manufacture of cement, concrete, asphalt and/or grouting material or also in earthworks.

11. Apparatus according to claim 10, characterized in that connected to the sorting device (6f, 7f) is a fan (14), the pressurized air flow (15, 33) produced by which is directed inside the sorting device (6f, If) from below obliquely or essentially directly upwards to lift the lighter particles that are smaller in their grain size upwards and away from the fan, and in that the material classified as waste has been sorted on a sorting line (5-5e) of the apparatus according to grain size into different products, the grain sizes of which are e.g. one or more of the following: D10 is between 0.5-2 pm; D50 is between 1-8 μπι; D97 is between 2-40 ]i and D100 is between 3-80 μπι.

12. Apparatus according to claim 10 or 11, characterized in that in the sorting line is at least one or, connected consecutively in series, two or more product silos (38, 39,

47, 48), and in that in the material flow a sorting device (6f, 7f) functioning essentially by means of an air flow (15, 33) is disposed on the front side of each product silo .

13. Apparatus according to claim 10 or 11, characterized in that the apparatus comprises at least a screening device (13) and a rotating throwing means (16) for delivering the material to be sorted into sorting hoppers (6-9), which sorting hoppers (6-9) are disposed consecutively in a sorting line (5-5e) and separated in the same sorting line (5-5e) from each other by means of dividing walls (10) that are open at their top end and adjustable in their height, and in that the air flow blown by the fan (14) at the first end of the sorting line (5) is directed from below obliquely upwards towards the material flow dropping into the first sorting hopper (6), and which fan (14) is arranged to blow the particles (12d) that are lightest and smallest in their grain size over the sorting hoppers (6-8) into the farthest sorting hopper (9) as viewed from the fan (14), the particles (12c) that are second lightest and second smallest in their grain size over the sorting hoppers (6-7) into the second farthest sorting hopper (8) from the fan (14) and the particles (12b) that are next lightest and next smallest in their grain size over the sorting hopper (6) into the other sorting hopper (7) preceding the second farthest sorting hopper (8) from the fan (14), and in that the apparatus comprises a plurality of sorting lines (5-5e) disposed side by side with each other and intended for the same or different waste, each of which sorting lines is arranged to sort wastes into different ^■ products according to sorted grain size into their own product tanks.

14. Apparatus according to any of the preceding claims 10- 13, characterized in that the apparatus comprises adjustment means for adjusting the direction and/or strength of the air flow brought about by a fan (14) in such a way that as a result of the sorting the desired amount of products of a predetermined grain size can be obtained in the sorting hoppers (6-9) or the product silos (38, 39, 47, 48) .

15. Product containing a material classified as waste and cement, characterized in that a material classified as waste, such as fly ash, that is of a set grain size and sorted into grain size classes is mixed into the cement as an additive.

16. Product according to claim 15, characterized in that the grain size of the particles (54) of a material that is classified as waste, such as fly ash, and is to be mixed as an additive into cement is smaller than the grain size of the cement particles (55), and the particles (54) of a material that is classified as waste, such as of fly ash, are arranged in cement gel (50) essentially to fill the spaces between the cement particles (55), in this case the grain size of a particle (54) of a material that is classified as waste, such as of fly ash, in the cement gel is e.g. one or more of the following: D10 is between 0.5-2 ]im; D50 is between 1-8 μπι; D97 is between 2-40 μπι and D100 is between 3-80 μπι.

17. Product according to claim 15 or 16, characterized in that fly ash. is mixed as an additive into cement to be used in the manufacture of concrete, the fly ash being approx. 2-14% of the amount of cement, suitably e.g. approx. 3-12% and preferably e.g. approx. 5-10% or whatever suitable percentage whatsoever of the ranges presented above, i.e. 4, 6, 7, 8, 9, 11 or 13 percent or parts thereof.

18. Use of a material classified as waste and sorted according to grain size into different products with the method according to claim 1 and/or with the apparatus according to claim 10 as an additive to cement, as an additive to concrete, as an additive to asphalt, as an additive to grouting material, as an additive to impregnating agent and/or as an earthworks material.