SK153699A3 - METHOD AND DEVICE FOR PRODUCING STORAGE MINERAL CONSTITUENTS TOì (54) IMMOBILIZE HARMFUL SUBSTANCES AND FOR PRODUCING COMPO - Google Patents

Abstract

The invention relates to a method and device for producing storage mineral constituents to immobilize harmful substances and to produce building components, specially building slabs and mixtures. The storage minerals are obtained by mixing combustion residues with substances containing water and CaO and by heating them in a reactor until the water thus released reacts with the free CaO and the aluminates and silicates to form hydraulically active phases which store harmful substances. An inventive device is used to implement the above production method. The use of said minerals for the production of building components, specially building slabs and mixtures is also described.

Description

Process for producing a substance containing waste products, in particular Binders, which can be used as a building material and / or a pollutant immobilizer and a device for carrying out the process

Technical field

The invention relates to a process for the production of storage minerals for the immobilization of harmful substances and for the production of components, in particular building boards and mixtures, and also to an apparatus for carrying out the process.

BACKGROUND OF THE INVENTION

It is known that combustion residues are used to immobilize pollutants. When the ash and pollutant-containing substances are mixed in the presence of water, the mineral phases of the filtered ash and pollutants form so-called accumulation minerals, such as calcium aluminate and calcium silicate hydrate, which are resistant to elution. At the same time, the hydraulic ash components lead to consolidation so that the product can also be used as a building material. The drawback is that the content of the constituents constituting storage minerals is usually influenced in these balances. Greater reactivity is low and is not feasible by the addition of expensive additives such as calcium aluminates.

Kneading screws, kneaders and so-called drum kneaders are known for mixing bulk materials with water. DE 23 43 352, DE 24 41 674 and DE 35 43 745 disclose material mixing devices which have rotatable shafts with differently shaped blades inside the housing, thus forming a kneading device, so that after inserting the components into the filling system, forms a homogeneous mixture which is removed or pumped from the mixer at the end of the tubular housing.

These mixers are suitable for the production of mortar, casting materials and concrete. Controlled heat treatment of the components of the mixture to induce thermal reactions is not possible.

It is known to manufacture so-called gypsum boards from gypsum resulting from the removal of sulfur from flue gas. These boards can only be used for building construction due to their water resistance and weather resistance.

insufficient for internal

It is further known to produce raw building board based on the sulfur of the developed method comprising aware of gypsum in the form of CaSO _fourth | _H2O well cement, slag, ashes, diatomaceous earth, sand, mineral and organic fibers, and flocculating aids (German published No. DE-OS 31 21 356).

In addition, there are also non-loadbearing compartments of vegetable raw materials such as ropes, hemp, straw and gypsum (DE-GM 297 14 805 and DE-GM 296 20 751).

All of these boards and partitions exhibit the drawbacks described in relation to plasterboard, namely the exclusive applicability to interior construction. Moreover, their strength and elasticity properties are very low, so that the area of their use is also very limited for interior construction.

Cement, α- and β-polyhydrate from natural gypsum or REA gypsum are known as binders for building boards.

It is known to mix flue gas desulfurization products consisting of sulphide and / or calcium sulphate, hydroxide or calcium carbonate with an amount of ash such that the next oxidation or calcination process (at 700 to 900 ° C) binds perfectly the free and released lime content with water for reactive aluminates and silicates (EP 0 348 756).

Heat treatment does not take place in the low temperature range of 100-600 ° C, but in the high temperature range. Only short-term hydration of calcium oxide to calcium hydroxide is also achieved. The hydration heat generated in the process and the associated vapor generation is not used in this process.

Furthermore, it is known to process pozzolanic ashes to improve the hardening of calcium hydroxide (EP 0 199 416).

Pouring hot water into a mixture of ash with calcium oxide and / or calcium hydroxide releases the hydration heat, which leads to a better curable product when the temperature rises to 100 ° C. The temperature range of 100 to 600 'C for processing the mixture is not affected. There is no zone heat treatment. The residence time of the mixture in the process is very long. The process is difficult and is practically unsuitable for large quantities being enforced.

It is known that the introduction of pollutant-containing alkaline earth aluminates into combustion and after subsequent hydration is converted back to laminar aluminates (DE 44 39 819). Combustion temperature is higher than 900 C. C. No method parameters or device details are published.

In addition, an apparatus for treating materials in a controlled atmosphere is known which is suitable for reducing metal oxides, for degassing coal, for burning lime, and for melting metals (WO 96/20381). The device does not guarantee a zone self-regulating heat treatment, it has only a mixer shaft, has no suction and return of the batches and cannot adjust the mixer wings.

Furthermore, it is known to produce an industrial waste immobilizing agent which is produced from cement, iron chloride, iron oxalate and amorphous alumosilicates (EP 0 600 128). This immobilizing agent must be produced in an inert gas environment because it normally oxidizes and loses its reducing effect. Moreover, it cannot be stored due to its high hygroscopy. The manufacture or preparation of such substances requires the addition of aluminosilicates. Equal amounts of cement are required for immobilization. No sludges of pollutants or waste products are used. The use of ash is not described, since the aluminosilicate is only present in undefined form in a portion of the ash glasses.

A drawback is the use of cement as a binder for the hydraulic hardening of the immobilisate, since it cannot achieve sufficient strengths and the permanent incorporation of pollutants. The production is two-stage.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a simple and inexpensive method to produce a product having adjustable and high reactivity for immobilizing pollutants and to provide a method and apparatus that ensures the mixing, conveying and controlled thermal treatment of various substances, particularly bulk materials, and stable components and / or mixtures that are universally applicable to both indoor and outdoor construction and consist of residual materials and natural materials.

It has been shown that this object can be achieved according to the invention by a process for the production of storage minerals.

SUMMARY OF THE INVENTION

The process for the production of a substance containing waste products, in particular a binder, which can be used as a building material and / or a pollutant immobilizer, in which the combustion residues and the water-containing substances are mixed according to the invention is based on the known combustion residues. with their free lime content, they are treated and mixed in a quantity of up to 50% by weight with water-containing substances in an amount of 30 to 90%, preferably 40 to 70%, and optionally with calcium oxide, in the reactor depending on the intended use in different zones at a temperature of 100 to 600 ° C, preferably 140 to 400 ° C and a different residence time of 5 to 120 minutes, preferably 5 to 30 minutes, whereby the crystalline water and / or the physically adhered and batch water is completely released and evaporated initiates the reaction of this water vapor with the calcium oxide contained in the ash with the The hydration heat generated in the process is utilized in the process, and the reaction product is again converted, with aluminates and feedstock silicates, into perfectly hydrated and reactively phase-enriched storage minerals which achieve a sustained accumulation of the pollutants contained in the water-containing substances.

Therefore, the ash from the filters is mixed with water-containing substances and optionally with calcium oxide. In particular, lime-free ash, such as brown coal ash and fluidized-bed ash or dry-sulfur ash, but also ash from garbage, sludge and hard coal incineration units, may be used as filter ash. The free lime of the ash used is sufficient to add 1 to 50% by weight of calcium oxide. Particularly favorable results for the formation of storage minerals can be obtained when 30 to 90% by weight, in particular 40 to 70% by weight, of the water-containing substance, based on the mixture as a whole, is used.

The addition of water-containing substances such as red sludge, aluminum hydroxide, waste water, silicate, ettringite and gypsum sludge has proven to be particularly advantageous. These materials can be used in varying degrees of drying.

The water may be in the state of crystalline water and / or physically adhered to the water. This offers the possibility of using the present substances in a wet state, i.e. without pre-treatment.

In the reactor, this mixture is exposed to a temperature that results in the release of crystalline water and / or physically adhered water. This temperature depends on the type of water-containing substance and is between 100 and 600 C. The water reacts with the added and in the free state of existing calcium oxide to form calcium hydroxide for a short time, which further reacts with aluminates and silicates on the above-described storage minerals.

The calcium oxide addition without the process according to the invention in no way leads to an increase in the reactive components, since there is no reaction between calcium oxide and aluminates with silicates. The amount of heat released during hydration promotes the formation of reactive mineral phases and results in energy savings from the outside to maintain the reaction temperature.

Substances containing crystalline water are converted into a partially or fully hydrated state by the process according to the invention. In the case of gypsum sludge, the phases of the polyhydrate and anhydrite are formed, thereby achieving an improved use of the product as a building material. According to the invention, the proportion of active ingredients can also be increased by the fact that substances containing crystalline water can be reactivated during dehydration.

For example, calcium aluminate sulfate hydrate is converted into anhydrite, bassanite, and portlandite forming storage minerals in the process of the invention. These components can be used to accumulate pollutants by creating the accumulating mineral ettringite.

The method according to the invention can be used to immobilize filter ash from filters that have not yet been matched due to the lack of reactivity (for example, filtered ash from brown and low-carbon coal with low calcium oxide contents).

Even filtered brown coal ash with high calcium oxide contents, which can be extinguished with difficulty due to the masked calcium oxide particles, can be extinguished particularly well by the process according to the invention. Under the conditions of the invention, the released water in the form of steam reacts with free calcium oxide independently of the masked surface. Hydration takes place incomplete and delayed in the usual water treatment. Accordingly, the process of the invention can also be used to extinguish these filtered brown coal ash so that it can be stored without difficulty. In addition, the filtered brown coal ash which has not otherwise been suitable for further use can be recovered by treatment according to the invention.

The process according to the invention leads not only to enriching the reactive mineral phases for the immobilization of pollutants, but also to increase the amount of hydraulically active components. This is reflected in the technical values of the building hardenable product (see application example).

This improvement in binding ability over the starting products allows use in the construction industry.

For carrying out the method according to the invention it is possible to use rotary tubes with mounted wings to transport and mix the material or the stationary or circulating fluidized bed.

The reactivity of the substance can be controlled by residence and temperature in the reactor. As the delay and temperature increase, phase formation increases.

The method according to the invention thus offers the possibility to adapt the reactivity of the product to the requirements for immobilization of pollutants or to the requirements for building material. Depending on the substances used, the delay may vary between 5 and 120 minutes.

According to the invention, the starting materials in the form of combustion residues and water-containing substances are fed into the elongated apparatus, which functions as a mixer and heat reactor, by means of a feed device and mixed, transported and heat treated simultaneously by several wing shafts. different at different temperatures and water vapor environments under different pressure conditions.

By adjusting the different temperatures in the different reactor zones and the different mixture residence times, varying the conveying speed and changing the zone length, products with different properties can be produced that are adapted to the intended immobilization of the pollutants and / or the construction application case.

The temperatures in the different zones are set at 100 to 400 ° C. Depending on the intended use of the product, the starting materials can be heat treated in temperature zones with rising or fluctuating temperatures. In order to initiate the necessary nucleation formation, the feedstock to be processed can be recycled in an amount of 1 to 10% of the total amount to start the heat treatment. A water vapor environment of 100 to 1000 l / m ³ is produced at pressures of 10 Pa to 1 MPa, preferably between 100 Pa to 0.5 MPa. The device is heated by gas or electrically.

The apparatus for carrying out the method according to the invention consists of a feeding device and a plurality of horizontal winged shafts with bearings, driven electrically by means of a gearbox, which are housed in an elongated heated housing having at the end an additional support bearing and outlet. The longitudinal housing has a backfeeding of vapors and has 2 to 8, preferably 4, temperature zones. These temperature zones are located at a length of 10 to 90%, preferably 10 to 50% of the length of the cabinet. The raw material temperatures in the zones are measured by thermocouples. Heat is supplied by a gas burner circularly positioned on the housing and / or by direct or indirect electrical heating, preferably in the upper part of the housing direct and in the lower part of the housing indirect heating. Steam heating is also possible. The casing is in a thermally insulated design. The wing shafts rotate in the same or the opposite direction and are adapted to the necessary material throughput. The angle of the wings can be adjusted to the shaft axis.

organic natural

According to the invention, a heat-treated mixture of combustion residues, substances containing water and calcium oxide can be used as a binder, mixed (as proven) with increasing raw materials and / or fibers from recycled textiles with filler and water, optionally followed by compression in molds and allowed to cure.

The combustion residues which may be used are filtered brown or black coal ash and filtered fluidized bed ash. The water-containing substances may be non-dewatered or partially dewatered gypsum REA. Suitable organic fibers are those of rope and / or hemp and / or sisal and / or reed and / or bamboo and / or textile.

Compared to the state of the art, these fibers are intended to produce markedly higher elastic values, which, with special binders and hence attaining high strength values, open up the possibility of producing larger components with thinner walls or smaller layer thicknesses and supporting elements. It is irrelevant whether it is used inside or outside the building, since the components are weather and frost resistant and are also not sensitive to contact with water.

The organic fibers are treated before being processed. As a binder for the mixture, shives which are not used in the treatment of fibers are used.

This has the advantage that the effect of these fillers significantly increases the heat dissipation of the mixture and reduces its weight, which extends the range of applications. Of course, the described compositions can be used as plasters, coatings or concrete and the like. The proportion of binder, organic fibers and filler is adapted to each application.

The invention is illustrated, but not limited, by the following examples. Percentages are by weight unless otherwise indicated.

In an intense mixer, 400 kg of ferric sulfate (40%) as Fe ₂ (SO ₄ ) ₃ .18H ₂ O is mixed with 50 kg of quick lime (5%) and 550 kg of filtered ash (55%) of the following composition: (37.1 % silica, 20.5% alumina, 2.9% iron oxide, 28.4% calcium oxide, 1.4%, free calcium oxide, 3.8% magnesium oxide, 4.7% sulfur trioxide, 4, 2% titanium dioxide). The mixture is fed into a rotary kiln using a screw conveyor. Indirect heating by a natural gas burner is set to 200 ° C in this rotary kiln. The mixture is held in a rotary kiln for 20 minutes and is withdrawn at the end as a dry mixture.

During the heat treatment, all of the crystalline water is released and consumed to extinguish the lime and to form accumulating mineral components (calcium aluminate and calcium silicate hydrates). These phases are demonstrated by X-ray diffraction.

The amount of heat released when extinguishing the amount of free lime of the mixture reduces gas consumption to maintain the temperature at 220 ° C by about 7.4%.

The resulting product is used to immobilize chromium containing soils. The chromium content of the treated eluate is 600 mg / l Cr ⁶⁺ . 50 kg of soil are mixed intensively in the mixer for 2 minutes with 20 kg of ash treated according to the invention with the addition of 18 kg of water. In another experiment, 20 kg of untreated ash was added to the same amount of loaded material.

The mixture is made into test rollers and stored wet after 28 days.

The following table shows the improvement of the immobilization and properties of the building material according to the invention over the deposition of unprocessed ash in the aged 28 days.

Processed Initial Concentration - Cr ⁶⁺ Concentration Compressive strength [N / mm ² ] Cr® ⁺ product in mg / l after immobilization in mg / l Filtered ash 600 125 7.5 Ash treated according to the invention 600 18 18.6

The immobilization rate in this example improves from 77% to 97% by treatment according to the invention. Compressive strength is increased by 148% using the inventive material.

Chromatettringite and monochromate accumulation minerals are proven by X-ray in the cured material.

The production method of the invention and the apparatus for carrying out the method of the invention are illustrated by the following figures.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1 is a longitudinal section of the device.

In FIG. 2 is a cross-sectional view of the apparatus A-A.

The apparatus for carrying out the method according to the invention consists of a feeder (1), a plurality of horizontal wing shafts (5) driven by a drive (2) via a gearbox (3), mounted in a front bearing (4) equipped with wings With an adjustable angle to the shaft axis, they are located in a zone-heated housing (6), with a return (9) exhaust vapor extraction (9), the device having at one end a further support (7) and a drain (8).

The starting materials are fed into the feeder 1 and passed into the casing 6 with the wing shafts 5, which are driven by the gearbox 2 with the gearbox 3 and mounted in the front bearing 4 and the rear bearing 7. The rotating wing shafts 5 convey and mix the starting materials evenly and controlled in the direction of outlet 8. The 10 t / h unit reactor can be, for example, 6 m long and 1 m in diameter.

The housing 6 is thermally insulated and is divided into temperature zones I to IV, which are equipped with electric heating. In the upper part of the housing 6 there is a direct electric heating and in the lower part an indirect electric heating. The set temperature in each zone is between 100 and 400 C. The heating is controlled separately for each zone by a computer-controlled program.

For example, Zone I can be at temperatures of 150-200 ° C, Zone II at 200-300 ° C, Zone III at 300-350 ° C, and Zone IV at 350-400 ° C.

The wing shafts 5 can be rotated at a different number of revolutions so that the retention of the mixture can be controlled. In the example, it could be 20 rpm.

Depending on the intended use of the product, they can be produced by targeted heat treatment in four temperature zones with a special residence time in the housing 6 of the substance which is approximately adapted to the intended use. They may exhibit either high or low often high strength, pressure, flexural strength or special thermal properties as well as very good immobilization properties.

The deployment of the manufactured product for various purposes is described in the following two exemplary embodiments. Again, percentages are by weight unless otherwise indicated.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

Building part

A binder consisting of a calcined mixture of 40% ettringite sludge and 60% black coal ash is used to make the component, especially the building board. This binder is intensively mixed with 1 to 10 t, preferably 3% of organic, e.g. hemp fiber, 1 to 3 cm in the dry state. The mixing is preferably done in a water-mixed mixer and is completed in two minutes. The water demand of the mixture is 20 to 40%, preferably 30%. The mixture is poured into molds and hydraulically separated. The dimensions of the mold are 2x1 m, while the building boards have a thickness of 10 to 20 mm.

After 28 days of storage, the test plates show the following values:

Crude density 1200 to 1400 kg / m 2

Flexural strength 14.4 N / mm ²

Compressive strength 28.7 N / mm ²

The boards are weather-resistant and have sufficient resistance to alternating freezing and dissolution, so that they are suitable for both indoor and outdoor construction.

Example 2

The binder used for the building thermal insulation material consists of a calcined mixture of 40% ettringite sludge and 60% ash from hard coal. To this binder, the plant fiber treatment residues are added in an amount of 10 to 80%, preferably 50%, and mixed intensively in the mixer for a maximum of two minutes. 15 to 25%, preferably 20% water is added.

The resulting mixture is poured on site to formwork, or processed into heat-insulating boards. Lambda = 0.01 to 0.04.

In this way, it is possible to produce highly heat-insulating walls of the inner and outer areas. Due to the complete incorporation and surrounding of the sheath with a binder, the fire resistance is very good. Compared to polysterol, better thermal insulation is achieved, with a clearly increased compressive strength of 2 to 8 N / mm ² , preferably 5 N / mm ² .

Of course, all the water-containing substances and combustion residues mentioned in the main claim can be used for the production of the boards, bricks and mixtures according to the invention. The proportions of binders in these products may be adapted to the intended use. They also depend on the calcination temperature and the residence time in the reactor. The optimum properties of the binder in relation to the admixed organic fibers are thus always given. The result is a product that can be manufactured in dimensions tailored to the purpose of use.

Surprisingly, the phenomenon of vapor deposition and swelling of this combination of starting materials, previously considered to be entirely unsuitable in the field of building material production, no longer occurs. As a result, even and calculable hydraulic coupling reactions occur, which guarantee the durability of the products.

Industrial usability

With the method according to the invention, it is possible to produce building boards with high thermal insulating ability, resistant to water and weathering, for internal and external components. In addition, the method makes it possible to immobilize the pollutants contained in the flue gas and to process the filtered ash from the combustion of brown and hard coal.

Claims (40)

PATENT Claims 162,9-9 ^ A method for producing a substance containing waste products, in particular a binder, which can be used as a building material and / or a pollutant immobilizer, wherein the combustion residues and the water-containing substances are mixed, characterized in that known combustion residues are dependent their free lime content is treated and mixed in a quantity of up to 50% by weight with water-containing substances in a quantity of 30 to 90%, preferably 40 to 70%, and optionally with calcium oxide in the reactor, depending on the intended use in different zones a temperature of 100 to 600 ° C, preferably 140 to 400 ° C and a different residence time of 5 to 120 minutes, preferably 5 to 30 minutes, whereby the crystalline water and / or the physically adhered and batch water is completely released and evaporated, initiation of the reaction of this water vapor with the calcium oxide contained in the ash with the The hydration heat generated is utilized in the process and the reaction product is again converted with the aluminates and silicates of the feedstocks into perfectly hydrated and reactively phase-enriched storage minerals which achieve a permanent accumulation of the pollutants contained in the water-containing substances. Method according to claim 1, characterized in that filtered ash from pulverized coal heating is used as the combustion residue. Method according to claim 1, characterized in that filtered ash from pulverized coal heating is used as the combustion residue. Method according to claim 1, characterized in that filtered ash from the fluidized bed combustion is used as the combustion residue. Method according to claim 1, characterized in that dry combustion products or shower absorption products are used as the combustion residue. Method according to claim 1, characterized in that filter ash from waste incineration is used as the combustion residue. Method according to claim 1, characterized in that filter ash from clarifying sludge combustion units is used as the combustion residue. Method according to claim 1, characterized in that the water-containing substances are used in the form of sludge and / or filter cakes and / or dried products. Method according to claim 1, characterized in that red sludge is used as the water-containing substance. Method according to claim 8, characterized in that aluminum-containing hydroxide is used as the water-containing substance. Method according to claim 8, characterized in that waste water treatment products are used as the water-containing substance. Method according to claim 8, characterized in that a silicate sludge is used as the water-containing substance. Method according to claim 8, characterized in that sulphate sludge is used as the water-containing substance. Method according to claim 8, characterized in that the water-containing substance is ettringite sludge. Method according to claim 8, characterized in that gypsum is used as the water-containing substance. Method according to claim 8, characterized in that wet ash and slag from incinerators are used as the water-containing substance. Method according to claims 1 to 16, characterized in that 1 to 50% by weight, in particular 1 to 20% by weight, of calcium oxide on the mixture as a whole is added. Process according to claim 1, characterized in that a rotary kiln is used as the reactor. Process according to claim 1, characterized in that a fluidized bed is used as the reactor. Method according to claims 1 to 19, characterized in that the resulting products are used as starting materials for building materials. Method for producing storage minerals according to claims Figures 1 to 20, characterized by walking substances, are residues containing substances which are fed to an elongated device, which works simultaneously as a mixer and a heat reactor, and which are mixed by means of several wing shafts depending on the offset of the starting substance. heat treatment is carried out in two to eight, preferably four temperature zones of not the same length, with temperatures of 100 to 400 ° C in a water vapor environment of 100 to 1000 l / m ³ at different pressure ratios of 10 Pa to 1 MPa, preferably 100 Pa to 0.5 MPa. The method is characterized in that the combustion and water supply means Method according to claim 21, characterized in that the starting materials are thermally treated at increasing temperatures as they pass through the apparatus. Method according to claims 21 and 22, characterized in that the starting materials are heat treated at alternating temperatures when passing through the apparatus. Method according to claims 21 and 23, characterized in that the product to be treated is fed back to the previous temperature zones. The method of claim 24, wherein the recycled product is recycled in an amount of 1 to 10% by weight of the total. Method according to claim 21, characterized in that the heat is supplied by gas or electric and / or steam heating. Apparatus for carrying out the method according to claims 1 to 26, characterized in that it comprises a feeder (1), a plurality of horizontal wing shafts (5) driven by a drive (2) via a gearbox (3) mounted in a front bearing (4). ), which are equipped with angle-adjustable sashes relative to the shaft axis, are located in a zone-heated (6) housing with a return (9) of backfeeding vapor pairs, the device having at one end an additional support (7) and outlet (8) ) Device according to claim 27, characterized in that each individual temperature zone (10) within the heated cabinet (6) is 10 to 90%, preferably 10 to 50% of the total length of the device. Apparatus according to claims 27 to 28, characterized in that thermocouples (11) are provided for measuring the temperature of the product in the temperature zones (10). Device according to claims 27 to 29, characterized in that the heat is supplied by a circular gas burner (12) and / or by direct or indirect electric heating and / or steam heating. Apparatus according to claims 27 to 30, characterized in that the direct electric heating is in the upper region (14) of the elongated housing (6) and the indirect heating is in the lower region (15) of the housing (6). Device according to claims 27 to 31, characterized in that the housing (6) is thermally insulated. Device according to claim 27, characterized in that the wing shafts (5) have the same or counter-rotating senses of rotation. The device according to claims 27 and 33, characterized in that the number of wing shafts (5) corresponds to the desired offset. Method for the deposition of storage minerals according to claims 1 to 20 for the production of building components, in particular as a starting material in a mixture with water, in which building boards and mixtures are used as a binder, binders and organic fibers being used. After combustion, the water-containing substances and the calcium oxide are preferably mixed with growing raw materials and / or organic fibers from recycled textiles, with natural filler and with water, optionally compressed in molds and allowed to cure. Process according to claim 35, characterized in that filtered ash is used as the combustion residue. The method according to claim 35, characterized in that non-dewatered or partially dewatered gypsum REA is used as water-containing binder materials for heat treatment in addition to water. Method according to claim 35, characterized in that flax and / or hemp and / or sisal and / or reeds and / or nessein, preferably plant parts of brenessel and / or textile, are used as organic fibers. 39. The method of claim 35, wherein the organic fibers are treated. 40. The method according to claims 35, 38 and 39, characterized in that shives, wood components of the plant material, which are omitted during the processing of organic fibers, are used as the natural filler.