DE19608093A1 - Utilising residues, wastes and low grade fuels in cement kiln - Google Patents

Abstract

Utilising residual and waste materials and low calorific value fuels in cement kilns involves: (a) subjecting the materials and fuels to gasification to produce a raw gas containing volatile heavy metals, volatile salts (especially alkali metal chlorides and other alkali metal salts) and optionally hydrogen chloride; (b) subjecting the raw gas to water scrubbing to remove the volatile heavy metals as a heavy metal sulphide sludge and to dissolve the volatile salts and any hydrogen chloride; and (c) supplying the resulting gas as fuel to at least part of the heating system of the cement kiln. Gasification is effected in a stream of a free oxygen-containing gasifying medium at above the melting temperature range of the mineral components so that the latter are melted and, after cooling, form fused granules for use as cement raw material.

Description

The invention relates to a method according to the preamble of the first Claim.

The invention is applicable wherever residues and waste materials as well Low calorific or high-ballast fuels, regardless of their nature and their content of toxic heavy metals, Chlorine compounds and salts, energetically and materially used and one or more cement rotary kilns are available.

Residual and waste materials are household waste, commercial waste, municipal and industrial sewage sludge, residues from treatment used industrial goods with organic components such as cables, old cars, Electronic waste, remnants from collections such as DSD and production residues from various technological Processes especially in the recycling industry. Low-calorific fuels are for example biofuels such as straw, wood, grass, leaves, special cultivated plants intended for energy use, but also polluted weak gases, e.g. landfill and sewage gases as well Solid / oil or water / solid slurries of various origins.

It is generally known to have high calorific wastes, e.g. B. old tires as Use additional fuel for cement kilns.

The direct energetic and material recycling of these materials will often complicated by their heterogeneous composition and  possibly high concentrations of inorganic and organic toxic substances such as heavy metals, dioxins and furans, organochlorine Compounds, salts and cyclic hydrocarbons. So be for example at the high firing temperatures in the cement rotary tube volatile heavy metals from residual and waste materials that are used directly be carried away with the exhaust gas, resulting in extensive exhaust gas purification plants to prevent their release into the atmosphere. Furthermore, the salts introduced with the residual and waste materials, such as alkali chlorides, to reduce the quality of the Cement.

On the other hand, it is known that residues and waste materials are also low in calorific values Fuels for the generation of combustible gases by gasification with air or technical oxygen. The gasification can as is known in the fluidized bed, see "Thermal Residual waste treatment by means of fluidized bed gasification ", 67th waste engineering Colloquium of the University of Stuttgart, in a fixed bed, e.g. B. according to DE 41 25 521 C1, or in the entrained flow, as u. a. DE 41 39 512 teaches to take place.

In fluidized bed gasification, the mineral components of the Starting materials as powdery fine-grained ash, the toxic Contains heavy metal compounds and an aftertreatment process, for example a subsequent glazing, with separate recording volatile, toxic heavy metals must be subjected. To the to secure required carbon turnover during gasification and comply with the maximum permissible carbon content for the landfill in the future are special technological measures such as internal or external Circulation of the gasification material required.  

The gasification temperatures must be below the ash melting or Ash softening point are to caking the Exclude ash particles. Low gasification temperatures in turn affect carbon turnover. Bring also higher alkali levels in the feed, this is especially true for biofuels, Household waste, but also with sewage sludge, the risk of eutectic Melting from ashes and fluidized bed with it, which in addition to forces lower gasification temperatures.

There are also gasification processes for lumpy or coarse-grained Fuels known, according to the fixed bed or moving bed principle work, for example according to DE 41 25 521 C. That according to such procedures generated gas is, however, with a more or less large proportion condensable, higher hydrocarbons loaded in the course of Gas treatment are separated as dusty tar, the Recovery is problematic due to its components. Also falls an aqueous condensate with considerable technical effort must be processed. DE 41 25 521 C1 therefore proposes this dust and coal water generated in the fixed bed gasification gas containing no intermediate cooling or condensation to supply secondary entrained flow stage for post-gasification. Act here the high technical effort and the considerable energy losses disadvantageous.

In the technology of gas generation is the gasification of fuels that are in a flowable state or transferred to this state can be known by partial oxidation in the entrained flow. Doing so the fuel with oxygen is often in shape even under increased pressure a flame reaction, into a gas rich in carbon monoxide and hydrogen transformed. It has been suggested for gas generation  Partial oxidation also carbon-based or combustible Residues and waste materials, as far as they flow into a Condition or can be brought into this. Examples of this are given in DE 28 31 208 and DE 38 20 013.

Homogeneous residues and waste materials such as contaminated oils, sludges and tars, which are pumpable, such as dried sewage sludge, biofuels, which can be conveyed pneumatically or like contaminated gases, landfill emissions, Production exhaust gases that are conveyed with blowers or compressors can be fed directly to the entrained-flow gasification stage.

To heterogeneously composed feedstocks, such as Household waste, commercial waste, waste wood or some biofuels from To develop entrained-current gasification, entrained-current gasification becomes a Pyrolysis upstream, as shown in DE 41 39 512.

With pyrolysis, the feed material becomes a brittle, easily grindable solid residue, the pyrolysis coke, and that from gaseous and vaporous Decomposition products converted pyrolysis gas converted. After Appropriate processing will be both pyrolysis coke and Pyrolysis gas and the eventual cooling of the pyrolysis gas condensates are fed to the entrained-flow gasification stage.

A key advantage of entrained-flow gasification is that Gasification temperature well above the melting temperature of the mineral components of the input material. The mineral Components are thus converted into a molten slag, which after cooling as glass-like granules and no after-treatment requirement. It is also advantageous that a hydrocarbon-free Raw synthesis gas is created.  

Plants for the thermal utilization of residual and waste materials as well low-calorie fuels generally have relatively low thermal Services. The common range is 10-50 MW. For example, one Plant for the energy recovery of household waste average Composition with a capacity of 100,000 Mg / a thermal Power of 35-40 MW. As a disadvantage of this low thermal output there are relatively high specific investment costs and low ones Efficiency of the associated energy conversion systems (e.g. gas turbine with waste heat recovery or gas engine), if, as usual, excess Energy is to be given in the form of electrical energy. Besides, is the effort required for the adequate separation of Pollutants, especially sulfur, relatively high. This affects the amount of the disposal costs.

The invention has for its object to a method combination create that allows residual and waste materials and low calorific value or ballast fuels regardless of their nature and their Content of toxic heavy metals, chlorine compounds and salts for to use cement production.

This object is achieved by the features of the first claim solved. The subclaims give advantageous refinements of Invention again.

The solution according to the invention is based on the residues and waste materials or the low calorific value or high ballast fuels, which because of their Pollutant content or its nature so far a cement kiln, in usually a rotary kiln, not fed as fuel and raw material could first be subjected to a gasification at which a  Raw gas containing volatile heavy metals, volatile salts and optionally hydrogen chloride is formed. Under the conditions of Gasification these volatile heavy metals lie like mercury, Cadmium, thallium, lead or zinc mainly in the form of sulfides. It it was found that the heavy metals practically quantitatively by a Water washing can be separated from the raw gas and used as a filterable sulfidic sludge is present in the washing water running off. Corresponding According to the invention, the washing water running off to separate the Heavy metal sludge subjected to filtration.

With the water wash, volatile, in the form of fog in the Salts containing raw gas, especially alkali chlorides, and possibly hydrogen chloride washed out of the gas. They remain dissolved in the wash water. That on this way of those harmful to the quality of the cement Components of cleaned gas is then the heating device of the cement kiln supplied as fuel. The gas is used before does not desulphurize the cement kiln, but contains from the feed for sulfur originating in the gasification reactor in the form of Hydrogen sulfide. When burning in a cement kiln, as a rule a rotary kiln, hydrogen sulfide is converted to sulfur dioxide, which then comes into contact with the cement components as far from these are bound by those set for environmental protection Limits for the SO₂ content in the exhaust gas from the cement kiln far be undercut. With the attachment of the sulfur to the The quality of the cement produced does not become cement components impaired.

It has proven advantageous to gasify in the form of entrained flow gasification with a gasification agent containing free oxygen Temperatures above the melting temperature range of the mineral  To carry out components of the input material. As a rule, as Gasifying agent technical oxygen with z. B. 96% O₂ used, however are also mixtures of technical oxygen with nitrogen, Carbon dioxide or water vapor possible. The gasification takes place in one free reaction space in the form of a flame reaction. The organic components and the carbon content completely into one CO and H₂-rich, hydrocarbon-free fuel gas implemented. The mineral components are at the reaction temperatures of z. B. Melted at 1500 ° C. They lie together with the raw gas cooling melt with granular structure.

As an advantage of entrained-flow gasification in the connection according to the invention with the operation of a cement kiln it turns out that the resultant Slag granulate is free from soluble alkali chlorides and also soluble Alkali and alkaline earth salts, of combustible carbon and of particularly critical volatile, toxic heavy metals, especially mercury, cadmium and thallium. Volatile Heavy metals such as nickel and chrome are resistant to elution in the glassy structure of the melt granules is integrated. It corresponds therefore the invention, the resulting melt granules as a raw material for the Use cement production. In particular, the granules Feeding the rotary kiln added or as a lean Cement clinker supplied after the fire and with it to the finished Cement be ground.

In many cases, they have not yet been used in rotary cement kilns suitable waste materials of very heterogeneous nature, such as household waste, municipal residual waste, commercial waste similar to household waste or shredder light goods available. This type of waste cannot be disposed of immediately or after simply drying and crushing the  Subject entrained-flow gasification. Therefore, in a manner known per se in such cases of the entrained-flow gasification stage, a homogenization and pre-treatment stage, consisting of

• - Pre-shredding to piece sizes of less than about 200 mm
• - thermal treatment at temperatures between 250 and 800 ° C by pyrolysis with exclusion of air or largely Air closure and conversion into a pyrolysis coke and gas and vaporous decomposition products of existing pyrolysis gas,
• - Separation of the pyrolysis gas from pyrolysis coke and supply of the Pyrolysis gas for entrained-flow gasification and
• - Grinding at least part of the pyrolysis coke and feeding of the ground coke to the entrained flow gasification reactor.

It can be advantageous if the pyrolysis coke is initially used with conventional Processing methods such as magnetic or eddy current separators ferrous metals and separated non-ferrous metals and a separate recycling are fed in before the remaining pyrolysis coke is ground up and entrained flow gasification is abandoned.

Depending on the nature of the waste to be used and the Overall design of the cement plant, it can be advantageous Pyrolysis coke or part of the pyrolysis coke, optionally after Separation of metal fractions, bypassing entrained-flow gasification can be used directly to heat the cement kiln. Such a solution lends itself particularly well if the cement rotary kiln for the Operation with coal dust is set up, the amount of pyrolysis coke compared to the gases and vapors volatile during pyrolysis or - due to the given composition of the used Waste - the pyrolysis coke only low with alkali salts, chlorine and undesirable heavy metals.  

It is also possible to feed the cement furnace directly Pyrolysis coke e.g. B. by water washing beforehand of soluble salts, especially to rid unwanted alkali salts. It is cheap at this embodiment of the invention when the wet by the laundry Pyrolysis coke if necessary together with hard coal or brown coal Is subjected to grinding drying before it is the dust burner of the Cement kiln is fed. That when washing out salts from the Coke-producing, salt-laden washing water can, for example be prepared together with the gas washing stage.

The pyrolysis can be carried out in a manner known per se externally heated rotary tube reactor can be used. The heating this reactor can e.g. B. with natural gas. It is according to the invention however, it is also possible to use a partial flow of water washed by volatile heavy metals, volatile salts and optionally Free hydrogen chloride, but sulfur-containing gas for heating the To use pyrolysis reactor. In this case, the combustion gases of the pyrolysis reactor combined with the exhaust gas from the cement kiln and with this together the exhaust gas purification in the form of a high quality Subject to dust removal. By binding to the exhaust gas from the Airborne dust carried in the cement kiln will ensure adequate desulfurization reached.

The advantages that can be achieved with the invention are that with the Combination of entrained-flow gasification according to the invention with or without Upstream pyrolysis and cement kiln so far not for this purpose pullable, polluted homogeneous, but also heterogeneous composite residues and waste materials energetically and materially for the Production of cement can be used without the burden of  Environment or degradation in cement quality may occur high thermal efficiencies can be achieved with low investment costs.

The process according to the invention is illustrated by three examples below are explained.

Example 1 describes the utilization of a heterogeneously composed waste material such as household waste according to FIG. 1.

The garbage delivered in silo vehicles is first emptied in a bunker 1 in order to be able to compensate for daily and weekly fluctuations in the accumulation. After pre-shredding using shredder shears 2 to piece sizes of approximately 100 mm, the domestic waste from a pyrolysis 3 is fed in, heating to 400 to 600 ° C. being carried out. Natural gas or recycled partially cleaned gas from our own generation can be used as heating gas. In the case of very damp domestic waste, there is the possibility, not shown in the diagram, of arranging a drying stage before pyrolysis 3 , which is heated with steam from the waste heat boiler connected downstream of the entrained-flow gasification reactor. In a separation chamber 4 downstream of the pyrolysis, the volatile gaseous and vaporous pyrolysis products, the pyrolysis gas, are separated from the solid pyrolysis coke.

In the simplified cooling and condensation 5 , the pyrolysis gas is cooled to approx. 60 ° C. An oil-water mixture condenses out, which also carries the residual dust carried by the pyrolysis gas from the separation chamber 4 . The cooled pyrolysis gas and the oil / water / dust mixture are fed with a compressor 6 or a pump 7 to the entrained-flow gasification reactor 8 operated under a pressure of 5 bar. Alternatively, the uncooled pyrolysis gas, including its oil and water vapor content, can be fed to the entrained-flow gasifier. However, because of the difficulty in compressing hot gases loaded with oil vapors, the pressure of the gasification reactor is reduced.

The pyrolysis coke separated from the pyrolysis gas in the separator 4 first passes through a magnetic separator 9 and an eddy current separator 10 for separating ferrous and non-ferrous metal fractions. The remaining pyrolysis coke is brought to a fineness of less than 1 mm in the mill 11 , here a ball mill, and is added to the entrained-flow gasification reactor 8 by pneumatic means.

In the reaction chamber of the gasification reactor 8 , the pyrolysis products supplied are reacted with oxygen in a flame reaction. This creates a hydrocarbon-free, flammable raw gas with H₂ and CO as the main components. By adjusting the ratio of oxygen to combustible components of the pyrolysis products, the gasification temperature which arises in the reaction space can be influenced. It is chosen so that the mineral components of the feed are melted. Usually temperatures above 1300 ° C are necessary.

Under the conditions of gasification become volatile, with the Heavy metals such as mercury, cadmium, Thallium, lead or zinc evaporates and is absorbed by the hot raw gas. The same applies to alkali salts. Organic chlorine compounds will fully implemented. The resulting hydrogen chloride remains hot Raw gas, possibly also after binding to excess alkalis in Form of evaporated salts. It is also characteristic that  Sulfur compounds in the feed converted to hydrogen sulfide will.

The raw gas formed during the gasification and loaded with heavy metal and salt vapors and the molten slag pass together into a quench chamber 12 downstream of the reaction chamber, in which spontaneous cooling takes place by injecting water down to the dew point of the raw gas which is dependent on the pressure in the gasification reactor.

Contact with water causes the slag to solidify, which breaks down into fine-grained melt granules. It is discharged via a lock 13 and a water-filled discharge trough 22 .

Starting in the quench room and continuing in the downstream venturi scrubber 14 , the raw gas is intensively water-washed. Alkali salts or still free hydrogen chloride are dissolved from the wash water, while the heavy metals are absorbed virtually quantitatively as sulfidic sludge from the wash water under the action of the sulfur content.

At a gasification pressure of approx. 5 bar, the raw gas saturated with water vapor and freed of alkali salts and heavy metals leaves the venturi scrubber 14 at a temperature of approx. 135 ° C. It passes through a heat exchanger designed as a waste heat boiler 15 , in which the now partially cleaned raw gas is further cooled with the formation of low-pressure steam and the majority of the saturated water vapor is condensed.

The partially cleaned but still hydrogen sulfide gas is now fed to the burner of the cement kiln, a rotary kiln 16 . With combustion in a rotary kiln with excess air, the hydrogen sulfide content is converted to sulfur dioxide, but is practically quantitatively absorbed by the fuel. The exhaust gas treatment 17 following the rotary kiln 16 according to the technology customary in the cement industry is limited in addition to the heat recovery for the preheating of the combustion material to a dedusting of the exhaust gases before the cleaned gas is expelled via the chimney 18 .

The melt granulate obtained during gasification becomes the raw material batch added for the cement kiln.

The scrubbing water, which is expelled from the quench chamber 12 and the sump of the venturi scrubber 14 and is loaded with salts and sulfidic heavy metals, passes through a filter stage 19 in which the heavy metal sludge is separated off. A partial flow of the filtered water is returned to the quenching and washing circuit together with the condensate obtained in the waste heat boiler 15 . The rest goes to the evaporation stage 20 , in which a mixed salt is obtained. The resulting clean condensate is available for technological purposes.

The heavy metal sludge can in principle be fed to a non-ferrous metal smelter for recycling, since e.g. B. zinc levels up to 8%, lead levels up to about 2% can occur. Alternatively, an underground landfill is possible for the relatively very small amount. The same applies to the mixed salt from the evaporation stage 20 .

The pyrolysis reactor 3 is heated with a partial flow of the gas generated and partially cleaned by entrained flow gasification.

With regard to the sulfur content of this gas, the flue gas generated during heating is added to the exhaust gas stream of the cement rotary kiln 16 , specifically before the exhaust gas treatment 17 . In this way it is ensured that the SO₂ content from the fly dust of the cement kiln exhaust gas is almost completely bound.

Example 2

The second exemplary embodiment, see also FIG. 2, relates to the recycling of a heterogeneously composed commercial waste. The design of the method largely corresponds to the first embodiment. However, after the metal fractions have been separated off, the pyrolysis coke is subjected to a water wash 21 in order to remove salts, essentially sodium, potassium and calcium chloride, contained in the coke. The washed pyrolysis coke is used directly as a fuel component for heating the rotary kiln 16 after appropriate processing 22 , for example after mill drying.

The embodiment of the method shown in this example is particularly advantageous when the amount of pyrolysis coke is small in relation to the amount under the pyrolysis conditions volatile gases and vapors.

The commercial waste used in the example contained larger proportions Plastic waste, including polyvinyl chloride waste, from the Scrapping of household appliances. This was the condition.

In this example, use is also made of the fact that in the pyrolysis of waste of the type described, a considerable part of harmful, volatile heavy metals, in particular cadmium and mercury, becomes volatile and with the pyrolysis gas or with the mixture of condensates and fly dust separated from the pyrolysis gas subjected to gasification and, as explained in more detail in the first exemplary embodiment, is separated from the raw gas generated in the gasification reactor 8 . This ensures that the cement kiln in particular is not contaminated with cadmium and mercury from the waste.

It was also found that pyrolysis decomposes organic chlorine compounds in the feedstocks, especially chlorine-containing plastics, to the extent that chlorine compounds remain in the pyrolysis coke only in the form of soluble salts, especially as sodium and potassium chloride. These salts are separated from the pyrolysis coke by the water wash 21 before it is fed to the rotary kiln 16 as fuel.

Contained in the feed or arising in the course of pyrolysis volatile organic chlorine compounds, including toxic compounds such as polychlorinated biphenyls, dioxins and furans, go the way Gasification and are completely destroyed there. The resulting ones Salts or hydrogen chloride are as described above from the Gasification gas separated and so before entering the cement kiln held back.

Example 3

As can be seen from FIG. 3, the method according to the invention is considerably simplified if waste materials are available for recycling which are already in a flowable, that is to say hydraulically or pneumatically conveyable, state or can be brought into such a state by simple pretreatment stages such as drying and / or comminution.

In this case pyrolysis is not used. Liquid and slurry-like feedstocks are fed directly to the gasification reactor 8 via a pump 7 A, dust-like feedstocks via a pneumatic dense flow conveying and metering system 22 which is only shown schematically in FIG. 3 and are reacted there with oxygen. The process elements following the gasification are identical to the first embodiment. Feedstocks suitable for this embodiment of the process are waste oils heavily contaminated with organic chlorine compounds and possibly volatile heavy metals and sulfur, fractions of waste oil processing and oil sludges, which are generally used without further pretreatment. Municipal or industrial sewage sludge that is heavily contaminated with volatile heavy metals is particularly suitable. Pretreatment by mechanical pre-dewatering, drying and grinding is usually required here. The dust-like feed material is fed pneumatically to the gasification reactor under pressure.

Volatile heavy metals and chlorine from the feed material go almost completely into the gas formed in the gasification stage and are taken up by the wash water in the quench chamber 12 and in the downstream venturi scrubber 14 , so that the gas fed to the burner of the rotary kiln 16 is free of these pollutants, but still contains sulfur is.

It is clear to the person skilled in the art that the examples 1, 2 and 3 illustrated embodiments of the invention can also be combined can that heterogeneous waste materials, for example household waste, the Path goes through pyrolysis while at the same time being disposed of Sewage sludge after mechanical pre-dewatering and drying separately  or ground up together with the pyrolysis coke and on pneumatic way is given directly to the gasification reactor.

Claims (13)

1. Process for recycling residual and waste materials as well as low calorific fuels in cement kilns, characterized in that
that the residues and waste materials and low calorific or ballast-rich fuels are subjected to gasification, in which a raw gas with contents of volatile heavy metals, volatile salts, in particular alkali metal chlorides and other alkali metal salts, and possibly hydrogen chloride is formed,
the raw gas is subjected to a water wash, the volatile heavy metals being obtained as heavy metal sulfides in the form of a precipitated sludge and the volatile salts and possibly the hydrogen chloride being dissolved in the wash water
and the gas freed from volatile heavy metals, volatile salts and optionally hydrogen chloride is supplied as fuel to at least part of the heating device of the cement kiln. 2. The method according to claim 1, characterized, that the gasification in the form of entrained-flow gasification with a free Gasifying agent containing oxygen at temperatures above of the melting temperature range of the mineral components of the Residual and waste materials as well as low calorific or high ballast Fuel expires, with the mineral components are melted and after cooling as melting granules available. 3. The method according to claim 2, characterized, that the melt granulate is added as a cement raw material.   4. The method according to claim 3, characterized, that the melting granulate the discharge material of the cement kiln is added and ground with this. 5. The method according to claim 2, characterized, that the melt granules are added to the loading of the cement kiln becomes. 6. The method according to any one of claims 2 to 5, wherein the residual and waste materials and low calorific value or high-ballast fuels have at least a part of heterogeneous constituents, such as domestic waste, municipal residual waste, commercial waste similar to household waste or light shredder, which cannot be comminuted or not economically comminuted,
characterized,
that at least the proportion of the heterogeneous components is subjected to a homogenization and pretreatment stage upstream of the entrained-flow gasification, consisting of

• - Pre-shredding to piece sizes of less than about 200 mm
• - Thermal treatment at temperatures in the range between 250 and 800 ° C by pyrolysis and conversion into a pyrolysis coke and a pyrolysis gas consisting of gaseous and vaporous decomposition products
• - Separation of the pyrolysis gas from pyrolysis coke and feed for entrained-flow gasification
• - Grinding at least a part of the pyrolysis coke and supply for entrained-flow gasification.

7. The method according to claim 6, characterized, that from the pyrolysis coke fractions of iron and Separated nonferrous metals and the remaining part of the Pyrolysis coke ground and fed to entrained-flow gasification becomes.   8. The method according to any one of claims 2 to 5, wherein the residual and waste materials as well as low calorific or ballast-rich fuels have at least a part of heterogeneous constituents such as domestic waste, municipal residual waste, commercial waste similar to household waste or light shredder that cannot be comminuted economically or economically,
characterized,
that at least the proportion of the heterogeneous components is subjected to a homogenization and pretreatment stage upstream of the entrained-flow gasification, consisting of

• - Pre-shredding to piece sizes of less than about 200 mm
• - Thermal treatment at temperatures between 250 and 800 ° C by pyrolysis and conversion into a pyrolysis coke and a pyrolysis gas consisting of gaseous and vaporous decomposition products
• - Separation of the pyrolysis gas from the pyrolysis coke and supply of the pyrolysis gas for entrained-flow gasification

9. The method according to claim 8, characterized, that the pyrolysis coke separated from the pyrolysis gas at least a part is fed directly to the cement kiln. 10. The method according to claim 8, characterized, that the pyrolysis coke separated from the pyrolysis gas at least a part after separation of adhering salts, in particular of alkali salts is fed directly to the cement kiln. 11. The method according to claim 9 or 10, characterized, that from the pyrolysis coke fractions of iron and Non-ferrous metals are separated.   12. The method according to any one of claims 6 to 11, characterized, that that of volatile heavy metals, volatile salts and optionally hydrogen chloride freed gas in part for the Heating the pyrolysis and the resulting Combustion exhaust gas combined with the exhaust gas from the cement kiln and with this is subjected to exhaust gas cleaning together. 13. The method according to any one of claims 6 to 12, wherein the residual and Waste materials and low calorific or high-fiber fuels Have a proportion of flowable components, characterized, that the flowable components immediately, bypassing the Homogenization and pre-treatment stage of entrained-flow gasification be fed.