FI87229C - FRAME RELEASE FRAME PROCESSING FUNCTIONAL FUNCTION - Google Patents

Abstract

In a method for production of pressed pieces from wet waste 2,7,21, where the waste 2,7,21 is broken down and then compressed, it must be possible to press the wet waste 2,7,21 into pressed pieces without drying. This is achieved by mixing the wet waste 2,7 with a dry, moisture- absorbing and advantageously combustible material 14, which has a smaller particle size and which in particular is also waste, and then pressing it into pressed pieces. The invention also relates to a device for executing the method, which device comprises a mixing device which is provided with feeder devices 9,13 for wet waste 2,7,21 and for dry, advantageously combustible material 14 and which is connected to a pellet and/or briquette press 17,18 by means of a transport device 15. <IMAGE>

Description

87229

The invention relates to a method according to the preamble of claim 1.

Wet waste is problematic in terms of both its handling and disposal. This applies in particular to sewage sludge from municipal and industrial treatment plants. A few years ago 10 municipal sewage sludge was transported after partial treatment such as digestion, pasteurization, hygienization, etc. in many places for application to agricultural land. This cannot be done in practice over time. This is due to the harmful loads on the sludge caused by heavy metals and other problematic substances that dissolve in the soil and groundwater after application.

The following requirements can be deduced from the above problems.

The existing problem of wet waste must be solved in an environmentally friendly and cost-effective way.

Wet waste must be converted at a low cost into a form that can be recovered and, in this connection, converted into energy with existing technology.

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Utilization of energy in both solid waste (rubbish) and moist waste such as sewage sludge and agricultural and forestry waste.

30 Converting wet waste into a storage and transportable energy product.

Manufacturing of energy products in a regionally decentralized manner and their centralized utilization, which seems to be the best economically.

It is known to produce extrudates from waste in order to achieve, for example, a reduction in volume, an improvement in stacking and storage capacity and a simplification of transport, e.g. due to onward transfer to an incineration plant 35 2 87229. In this case, a distinction is made between a relatively low-pressure compression method and a relatively high-pressure compression method. In the first case, it is common to form the extrudates as a bond, i.e. to tie them into strips, ropes or braids. In the second case, bonding of the extrudate is not necessary, because the high compaction causes considerable hardening of the material, which creates strong extrudates.

WO application publication 81/03029 discloses a method for preparing ingots from solid and liquid waste. In this method, the mixed waste under light molding pressure is compressed into ingots. The final drying of this product is carried out in an aerobic digestion process, e.g. composting. Ingots prepared in this way must be stored for 20 days in order for the biological process to achieve the desired final moisture content and to be flammable.

Making extrudates from moist waste is therefore difficult because the moisture or water content of the waste must be reduced. This is especially true for extrudates that are compressed without bonding, as the high moisture content reduces the strength of the extrudate. This also applies to the braided extrudates mentioned above, as much higher requirements are placed on the strength of the braiding.

Reducing the moisture content of the waste can be achieved in different ways.

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The first possibility consists in removing water from the waste, which can occur during compression. This method can only be carried out with special pressing devices with drainage openings, in which case the difficulties due to blockages must be taken into account. 30 In addition, waste water is generated, which must be disposed of and, if necessary, collected. In addition, flammable components can escape with the wastewater, which is detrimental, especially to extrudates intended to serve as fuel.

35 It is also possible to reduce the moisture content of wet waste thermally in suitable equipment by supplying additional heat. This method of drying is expensive.

3 87229 The moisture content of the waste can be determined by both the composition of the waste and external influences, eg rain.

The object of the invention is to further develop a method of the type described above so that moist waste can be compressed into compacts without drying.

This object is solved by a solution according to the features of claim 1.

10

In both methods of the invention, the moist and optionally comminuted waste is mixed with a dry matter (carrier) and thus brought to a moisture content without drying, which is suitable for pressing the extrudates. The process according to the invention is particularly suitable for organic waste, since the moisture content of the extrudates produced by such a process according to the invention is relatively high. The compacts thus produced form a high-value fuel that can be used in known solid fuel burners and / or aroma or coal furnaces for chips or shavings.

20

In order to satisfactorily mix the wet waste with the dry matter, a relatively small particle size is required for the latter. For a small piece of wet waste, the particle size of the dry matter should not be substantially larger than the particle size of the wet waste. The moisture content of the dry absorbent material 25 should preferably be about 5% or less. It has been found that in the process according to the invention the fibrous, flaky and / or leaf-like substances are particularly well suited for reducing the moisture content. Preferably, the organic solids are mixed with the moist waste. In this case, it is advantageous to use fibrous, flake and / or leaf-like substances in the form of waste, and in particular to use substances which have been prepared from the waste according to claim 1 by a pretreatment process, such as fibrous, flake and / or leaf-like substances from organic substances, paper and / or plastic. In this way, no additives are needed, but the extrudates are made entirely of waste, which advantageously takes into account the general problem of waste disposal and improves the strength and flammability of the extrudates.

4 87229

The method according to the invention is also suitable for the removal and commercial use of waste and incinerators, in particular waste sludge, as claimed in claim 2, in which case extrudates are excellently suitable for incineration, the wet waste 5 and / or dry matter may contain a certain plastic suitable for incineration.

The mixing of lime has the advantage that it acts as a retarder inside the mold during the pressing step and thus generates additional resistance and thus compresses with higher densities and correspondingly higher specific weights are created.

It is also advantageous to mix sodium or sodium hydroxide solution with the waste, which acts as a plasticizer and corrosive medium with all kinds of waxy and resinous parts, as a result of which these parts can be compressed and bonded together.

In order for the waste to be compressed into relatively stable extrudates without special post-treatment, the moisture content of the waste should be in the range of approximately 15% according to claim 1, giving a residual or product moisture of about 7-9% after compression. This results in relatively stable extrudates which may only need to be cooled and which are thus ready for re-use, transport or immediate incineration without substantial post-treatment. This applies in particular to the compression of waste into relatively small compacts. In such a case, directional comminution must be ensured before pressing.

In the method according to claim 1, after pressing, a special post-treatment of the molds is possible, namely an aerobic fermentation process which results in biogenic drying due to the self-heating of the molds, whereby the molds acquire a mycelium. Thus, the strength of the extrudates and thus also the stackability is substantially improved. Especially suitable for aerobic fermentation are presses having a moisture or water content of about 25-75%, preferably about 40-60%. This water content can be achieved by compressing the extrudates with a low compressive force, in which case the compressive force must be dimensioned according to the water content. The water content, especially the upper limit of the above-mentioned range, has a lower strength of the extrudates and thus also a lower stackability than the above-mentioned extrudates with a higher compressive strength of approximately 15% water content, but higher extrudates In this way, compressive energy can be saved.

10 For the first case (water content about 25-75%), a surface pressure of about 400-500 N / cm2 is very suitable. In the second case (water content about 40-60%) good results have been obtained with a surface pressure of about 60-100 N / cm2.

Due to the low strength of the extrudates in the second case, the parallelepiped shape of the extrudates should be preferred so that, despite the relatively low strength, the extrudability of the extrudates is achieved for the aerobic fermentation process. , as a result of which the fermentation process and evaporation described above may occur. No water or moisture is introduced during this process. Experiments have shown that extrudates with a bottom surface area of about 250 x 800 mm and a height of about 200 mm are suitable.

The above-mentioned moist waste and the above-mentioned substances are thus transformed by the process according to the invention into valuable compacts which can be re-used as fuel and which can have the following compositions. A few examples: 30 Option 1 Wet part with 40% H20 Dry matter with 2% H20 Wet part: wood chips or bark or sawdust, etc.

"350 kg incl. 140 kg H 2 O) - 15.3% compression- 35 Dry matter 650 kg incl. 13 kg H 2 O) moisture 6 87229 H 2 O loss in compression 80 kg -7.3% product moisture

Option 2 5 Wet part with 25% H 2 O Dry matter with 5% H 2 O Wet part: as in option 1 "500 kg incl. 125 kg H 2 O) - 15% compression

Dry matter 500 kg incl. 25 kg H 2 O) moisture 10 H 2 O loss in compression 80 kg - 7% product moisture

Option 3 15 Wet part with 70% H20 Dry matter with 2% H20 Wet part: soft plants, grasses, mash from vodka bulbs, etc. "200 kg incl. 140 kg H20) - 15.6% compression

Dry matter 800 kg incl. 16 kg H 2 O) moisture H 2 O loss in compression 80 kg - 7.6% product- 20 moisture

Option 4 Wet part with 80% H20 Dry matter with 2% H20 25 Wet part: hygienized sludge from the treatment plant. . "180 kg incl. 144 kg H 2 O) - 16.4% compression

Dry matter 820 kg incl. 16.4 kg H 2 O) moisture H 2 O loss in compression 80 kg - 8.4% product moisture 30

Option 5 Wet part with 78% H 2 O Dry matter with 2% H 2 O Wet part: as above in option 4 35 "210 kg incl. 163 kg H 2 O) - 17.8% compression

Dry matter 760 kg incl. 15 kg H 2 O) moisture 87229

Lime 30 kg - - -) H 2 O loss in compression 90 kg - 8.8% product moisture 5 In all the examples (alternatives) described, lime can be added or mixed. Similarly, in Example 5, lime can be omitted. Lime is usually mixed in an amount of 3% by weight relative to the mixing agent.

10 Instead of the above-mentioned addition of lime, 30% sodium hydroxide solution can also be added.

Other advantages provided by the invention are briefly described below.

15 All low, moderately and strongly moist biomasses that are suitable for heating purposes and that are not or only difficult to use in their natural form can be converted into a solid form of heating product that has been brought to the desired humidity and is commercially usable. All wet parts with 20 different humidities can be treated immediately after the accumulation of individual components. It is possible to finely grind the wet parts to the size required for compression without pre-drying by mechanical equipment or long-term storage. It is possible to compress existing wet parts, such as sludge, sawdust, etc., which accumulate in fine form without first being pre-dried. Large wet items can be brought to a small space with high energy density without partial rot. Without pre-drying, the sludges can be compressed especially into heating products. Readily digestible biomasses can be converted into 30 strong storable products without thermal treatment. The products can be used in any solid fuel burner, even in fully automatic combustion plants that are used depending on the load. For the first time, sludges from treatment plants can be converted into dry, strong fuels without high energy consumption. The invention enables the production of 35 new raw materials, in which several hitherto wasted biomasses are brought privately into the dry matter or mixed with each other and the dry matter into an aesthetic and reusable fuel which provides substantial assistance in terms of maintenance and energy savings and thus offers considerable energy. service to the general public. In municipalities where there are already 5 similar heating plants, municipalities can operate their own plants, such as schools and spas, with alternative fuels produced in accordance with the invention in a crisis-safe and economically interesting manner.

The invention will now be described with reference to the preferred embodiments shown in the schematic drawing.

Figure 1 shows a flow chart for making extrudates from moist organic waste.

15

Figure 2 shows a flow chart for a modified manufacturing method.

Figure 3 shows a table of the mixing ratios of the extrudates.

Figure 4 shows a perspective view of a compact made by the method according to the invention.

Figures 5 and 6 show the stacking sequences of the extrudates.

Figure 7 shows a storage arrangement for the post-processing of extrudates. Figure 8 shows the final stock of extrudates.

Coarse waste 2 at the storage site 1, such as wet wood, shrubs, perennials, etc., is fed by means of the conveying device 3 shown by reference to a pre-shredder 4, which makes wood chips or coarse chips from them. which are then fed by means of a transport device 5 to a tank or silo 6. At the same time, pre-shredding 4 can also be fed to the silo 6, bypassing also small pieces of waste 7 from plantations and agriculture or 35 from plantations. The silo 6 is equipped with an unloading and dosing device (not shown), which enables the fines 11 in the form of a fine grinding mill to be charged evenly and continuously by means of the conveying device 9.

The post-grinder 11 is a commercially available hammer, impact or bang-5 mill with a sorting sieve structure (sieve sieves 8 mm in diameter). The purpose of the post-shredder 11 is to bring the partially pre-comminuted and partly small-piece material coming from the silo 6 to the desired final size, which is about 8 mm.

From the silo 12, a dry matter of leaf-like or fibrous material can be fed to the post-grinder 11 by means of a conveying device 13. The fibrous material 14 is below the desired grain size and thus does not load the grinder 11, but it is nevertheless intended that most of the water released during the grinding of the wet mixture is collected and discharged from the grinder 15. The amount of fibrous material 14 added depends on the moisture content of the moist waste present. In this case, a moisture content in the range of about 15% is desired. This moisture content prevents clogging of the fin.

The fibrous material 14 is preferably a material made from waste by a prefabrication process. Several Orfa methods, which are referred to in DE patent 31 05 597 and DE patent applications P 36 14 325.1 and P 36 14 324.3 and in another embodiment, are suitable for this. This method is taken into account. The fibrous material 14 has a moisture content of about 5% and is thus highly absorbent.

The post-shredder 11 is connected via a conveying device 15 to a feed device 16 for a pellet and / or briquette press 17,18, whereby the feed device 16 can be formed by means of a feed coil.

30

A direct conveying device 19 is formed between the silo 12 and the feed device 16, which enables the fibrous material to be compressed directly and alone •; : when the waste has no or few wet parts.

A container for receiving thickened sewage sludge from the treatment plant is arranged in front of the feed device 16, 10 87229 which is connected to the feed device 16 by means of a transport device 23. A mixer 24 is arranged in the transport device 23 and is also connected to a silo 12 via a transport device 25. the incoming dry matter to each other and 5 is conveyed to the feeder 16. The mixer 24 is a device on the market and is capable of continuous operation. Transport devices, e.g. 9,13,15,19,23,25, are each provided with a dosing device (not shown), for example at 26. Thus, it is possible to derive all components from the dosing, namely waste material from silo 6, fibrous material from silo 10 12, sewage sludge from tank 21, mixture from post-grinder 11 and the mixture from the mixer 24 individually or mixed to the feeder 16, which further mixes additives such as lime and / or sodium which can be metered into it by means of the feeders 27,28 from the tank 29,31 and conveys to the press or presses 17,18. In this way, power equalization independent of the post-grinder 11 and the mixer 24 in particular is possible. With regard to the purpose of the additives, reference is made to the effects described above.

The feed coil forming the feeder is a commercially available transport coil 20 with a length of about 3 m or more. This ensures that the materials, including any imported additives, are mixed efficiently.

The material introduced into the press 17 is formed under the high pressure prevailing inside the available matrix together with the frictional heat thus generated into the desired compacts (pellets) having the desired size, the diameter being 6-20 mm and the length 10-30 mm.

Briquettes 18 can be used to produce briquettes with large masses and dimensions 30, respectively, for example a diameter between 40-100 mm and a length between 200-300 mm. The method of prefabrication of compressible biomasses remains the same. The supply to the presses 17,18 can take place simultaneously or in each case also individually.

35 The hot presses from the press or presses 17,18 enter the cooling zone or the cooling device 32, where the presses are cooled to an ambient temperature of 11,872,229. In this case, the final hardening of the soft extrudates takes place in a warm state.

The cooling device 32 is likewise a machine available on the market. Once refrigerated, the extrudates can be stored and / or packaged and / or delivered to consumers (incinerators).

The extruders leave the device or apparatus ready for use, with a moisture content of about 5-10% and unlimited strength.

The following describes the individual stations of the embodiment according to Fig. 2.

15 As. 41: The base material is made from mixed industrial waste or preferably household waste.

As.42: Waste is pre-crushed and freed from ferrous metals.

Flat. 43: Next, they are chopped to a piece size with a maximum diameter of 10 mm.

20 As. 44: In the next step, they are dried to a water content of 5%.

Flat. 45: The dry matter is separated into an inorganic ballast fraction and an organic base fraction by sieving and wind screening.

Flat. 46: Due to the pre-preparation process, the dry organic fraction is flake-like, leafy, fibrous and / or granular, which is important for post-treatment.

Flat. 47: The dry fraction is dispensed by means of a commercially available device according to weight or volume and passed on to the mixture at 61.

30 As. 51- These are conventional equipment and process steps in existing treatment plants that produce fresh sludge containing about 2% dry matter, sanitized sludge containing about 5% dry matter, and dried sludge containing 30% dry matter.

- - 35 As. 56: Dosing: The desired sludges (As. 53, 54 and 55) are fed individually or in the desired compositions to the i2 87229 dosing device on the market, which delivers the required amount to position 61.

As.61: Here, the mixing of the sewage sludge and the dry fraction takes place using a suitable mixer, such as a conventional twin-axle-5 mixer or a centrifugal mixer, which is used in the particle board industry for the expression of wood chips. The mixing device must be designed in such a way that a thorough mixing is guaranteed so that the moisture is immediately equalized between the slurry and the dry fraction.

10 As. 62: This is where the extrusion takes place in a piston or extruder, such as is needed in the brick industry or for the production of briquettes. The compression should preferably be adjustable so that the density of the compresses can be adjusted. The extrudates are usually pressed at a pressure of between 40 and 70 bar. The compression pressure depends on the quality of the slurry (As. 53, 54 and 55) and the selected mixing ratio (see table in Figure 3). The size and shape of the extrudates are chosen so that a) optimal biogenic fermentation drying is guaranteed and b) stacking and stacking, preferably on a substrate, e.g. a Euro pallet, is guaranteed and possible. Thus, space-saving storage and mechanical transport (see Figures 4-25 8) are guaranteed, in which the extrudates are indicated by reference numeral 71. The preferred size of the parallelepiped-shaped extrudate 71 has proven to be such that the bottom surface is about 250 x 800 mm and the height is 200 mm. .

30 As. 63: Stacking: The extrudates 71 formed in station 63 are transferred by a stacking device and stacked on a desired substrate, e.g. a grate 72 or a transport pallet 73. These devices are likewise available on the market. When stacking and arranging the extrudates 71, it must be taken into account that a) air (space A) can circulate between the extrudates to allow the evolving steam to escape, and b) only so many layers are stacked on top of each other that the top layer does not form the lowest layer (usually it is possible 4-5 floors). The press stacks 74 can be transported by a transport device, e.g. a forklift, to a biological dry store (Figure 7).

10 As. 64: Biogenic drying: The drying storage should preferably be established with guaranteed ventilation between stacks 74. Preferably, suction is generated in this covered space by means of a weak vacuum system.

Under the conditions described above, such as: - mixing ratio, - moisture content of the mixing agent, - density and compression pressure during the production of the extrudates 71, and - the dry organic fraction introduced into the mixture with the sludge 20 containing microorganisms, the aerobic fermentation process starts immediately.

The biological fermentation process induces self-heating within a few hours. Heating usually rises to 70-80 ° C within 5 days. These temperatures indicate that large amounts of water evaporate. The process lasts until the mixed oxygen is used. As soon as the body has used up oxygen, the fermentation process slows down and the extrudates cool. The cooling phase usually lasts (based on experiments) 4-5 days. During cooling, the fungal mycelium formation phase begins, in which the extrudates are completely filled with the fungal mycelium. Due to the formation of the fungal mycelium, the extrudates are strengthened, which leads to strengthening. As the extrudates dry further, the fermentation process is abruptly interrupted. Fungal mycelium is also removed by drying and stiffened. With the help of the dried mushroom mycelium, the extrudates get their own shape stability, which allows the stacking or stacking. Process details of the experiments are shown in the table in Figure 3.

Flat. 65: Storage: The biologically dried extrudates 71 described at station 64 are dried in a rearranged storage hall to a final or adjusted final moisture content to the desired water content. With the help of final storage, the final moisture of the extrudates and thus the heat content can be widely adjusted. The final storage only needs to be covered to prevent rainwater from entering the extrudates.

10 As. 66: From the stock (pos. 65), the extrudates 71 can be fed to the desired operating position and converted into energy as required. All furnace units, such as a grate furnace, fluidized bed, pyrolysis, gasification, etc., equipped with suitable gas cleaning devices, are suitable for generating heat from the fuel (presses) described above.

As already mentioned in the previous embodiment, the positions 41-46 are described in DE patent 31 05 597 and DE patent applications P 36 14 324.3 and P 36 14 325.1, which are taken into account.

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Within the scope of the invention, it is possible and advantageous to further separate the granular, flaky, leafy and / or fibrous dry fractions and to use only the leafy and / or fibrous fractions (light fractions), in particular organic substances, for the aerobic fermentation process.

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Claims (2)

1. A process for producing extrudates from moist waste, characterized in that: 5. the moist waste is mixed with a desiccant produced separately from household and industrial waste and which is fibrous, flaky and / or leafy, - has a residual moisture content of 5% or less, the water content of the waste is 25-75%, preferably 40-60%, 10. the moist waste and desiccant are mixed with a compression moisture of about 15%, - and compressed without finishing into finished compacts, - the final moisture content of the compacts after compression is 7-9%. Method according to Claim 1, characterized in that the waste is sewage sludge and / or mash and the waste is mixed with brewery mash, sewage sludge, lime and / or soda liquor. 16 87229