MXPA97008305A - Method for the total utilization of emission-free material, by recycling at high temperature and by specific fractional conversion of raw synthesis gas materials results - Google Patents

Abstract

The invention relates to a method and devices for use of total material, free of emissions, of all the ingredients of industrial waste of all kinds by gasification at high temperatures and processing of the resulting crude synthesis gas, so that the Fractional conversion of all the main ingredients such as hydrogen, carbon monoxide and carbon dioxide, and also the ingredients such as water, heavy metals, sulfur, chlorine and sodium, can be supplied for reuse as a raw or untreated material

Description

ODE FOR THE TOTAL USE OF EMISSIONS. BY RECITATED TO HIGH TBffl > E A.TT] RA AND BY SPECIFIC FRACCIQN CONVERSION OF QAS MATERIAL DESCRIPTION OF THE INVENTION The invention relates to a method of recovering usable materials, or to make them useful, from raw or untreated synthesis gas, which is produced during the gasification of community wastes and other wastes, preferably also for toxic and special waste from which < any type, according to the preamble to claim 1, and with a device for carrying out the method. The waste gasification becomes increasingly important as a method for the thermal treatment of waste, also due to its great potential to destroy toxins. In addition, the synthesis gas is obtained as a thermal or chemically usable material, and also Fe metals and vitrified minerals, which are presented in usable form directly. However, the crude synthesis gas also contains heavy metals, chlorine and sulfur. These elements - in themselves useful as "chemical base" materials - are for toxins biosphere REF: 25988 environmental (heavy metals) or their reaction products, especially moisture, are constitutive ingredients of acid rain. Therefore, it is essential in washing the gas from the crude synthesis gas and, for a long time, it has been part of the prior art in many different embodiments. Generally, adsorption by filters (textile) (activated carbon, precipitation reactions and ion exchange) is used to clean, that is, also for the cleaning of synthesis gas, and in various combinations. The sludge and dust "that result from it are, in the current state of the art, a special waste, which must be eliminated in a costly manner by discharge. The volume of this special waste, measured as the output volume of the waste is in fact small, although the discharge of waste materials from the gas wash is an unsatisfactory solution: each discharge of special waste represents a residual risk to the environment, and - valuable industrially usable materials are separated from the circulation of • materials in the economy as desirable and requested by legislation.

The object of the invention is therefore to establish a method for the recovery of useful materials from crude synthesis gas during the waste gasification and therefore to design the waste gasification so that it is free of residual materials that can be downloaded. A further objective of the invention is to exclude stresses in the environment due to waste water. Finally, it is also an object of the invention to establish a device for carrying out the method according to the invention. As far as the method is concerned, this objective is carried out by the characterizing part of claim 1 and the sub-claims indicate further advantageous developments thereof. With respect to the device, claim 11 establishes the solution with further advantageous developments in the sub-claims. By converting in stages the content that appears as harmful materials in the raw synthesis gas to make it usable materials separately, the stages of wet treatment heated separately, the condition is satisfied for material recovery, conversion, that is, the transfer of materials in a recoverable form, in separately heatable, separate wet treatment stages, allows the Conversion conditions are adapted to optimal specific content materials. The temperature of the treatment steps in this case is more appropriately predetermined by the stage condensation, necessarily for the partial separation of the water vapor contained in the crude synthesis gas. The contained materials converted into usable materials from the separate conversion stages are then recovered in such a way that the solutions and condensates of the different conversion stages are combined and subjected to precipitation reactions in successive stages and to ion exchange processes., with recovery of the process water. Subsequent cold drying of the cleaned synthesis gas of the undesirable ingredients removes the residual moisture which then, together with the recovered process water, is passed back to the individual conversion stages, so that a circuit or cycle is obtained. water with a minor process closed. Therefore, by virtue of the fact that in the first place, during the cleaning of the crude synthesis gas, its ingredients are not only separated, but are converted before separation into a form which is reusable directly after separation. , the condition for a waste-free synthesis gas cleaning is satisfied, and also since the process water and the condensates from the conversion stages are subjected to common to reactions by precipitation stages and ion exchange, this provides a simple possibility to recover useful materials, based on their reactions in the conversion stages and the type of precipitation and ion exchange reaction that can be designed to coordinate between yes. The ingredients of the crude synthesis gas can be directed, if necessary, separately, that is, without conversion, which are then only obtained in the sense of the inventive idea if the ingredient is industrially utilizable in this form. Therefore, it may be advantageous to establish a separation stage catalytically operated and operated separately in the flow path of the crude synthesis gas. Such a possible separation exists, for example, for sulfur, which can be separated as an element with the help of the catalytic action method called "Sulferox", and in this form is a material which is usable in many areas. Prior to the cleaning of the crude synthesis gas in the current state of the art there is usually a shock type cooling directly after it leaves the high temperature reactor, in order to suppress the "de-novo" synthesis of the materials harmful organic In this case, the crude synthesis gas flows to through a sprinkling of water. According to the invention, this water spray, referred to as "cooling" can be used as the first conversion stage, as long as it is operated as a spray cooling in the pH range of < 5, that is, in the acid interval. Therefore, hydrogen chloride and heavy metals are converted to recoverable chlorides. After acid spray cooling, the crude synthesis gas passes through a wet treatment step to basically adjust and neutralize. During this step its temperature is adjusted optimally for the subsequent specific conversion stages. Therefore, a plurality of advantages arise: The water vapor contained in the crude synthesis gas condenses on cooling and does not prevent subsequent conversions; The water transported from the spray cooling is retained in the neutralizing stage and is used again due to the neutralization; The crude synthesis gas enters after the treatment stages, at an optimum temperature, so that the point of reactions is improved and accelerated. It is particularly advantageous if the crude synthesis gas heated in this way subsequently passes through several stages of conversion, which is placed in common container, however which is subdivided according to the stages provided. Such an arrangement is described, for example, in EP 95 10 6932.7 under the name "combination washing machine". Within this combination washer, a powder removal step can be more conveniently placed, more advantageously with a dust removal agent of a viscosity greater than that of water, for example glycerin. The agent to remove the dust in this way releases dust and regenerates in its own circuit, the powder is returned to the high temperature reactor and at this point participates again in the gasification reaction. Therefore, the conversion, associated with the flow path of the synthesis gas, of harmful elements contained therein, in recoverable useful materials and their transfer to the waters in the various conversion stages is completed. The synthesis gas cleaned in this manner from undesirable mixtures, if necessary, can be returned for material utilization and / or thermal utilization, after additional cold drying to remove any remaining residual moisture, after renewed heating of the synthesis gas dry with subsequent passage through an activated carbon filter. The cold drying can be carried out in a separate treatment step. It is advantageous to integrate this stage in the combination converter. The waste heat from this stage and the spray cooling can be decoupled, if required, and used to equalize the temperature of the conversion stages, and to heat the gas. The solutions and condensates of the conversion and cooling stages, which contain in solution the usable materials that are to be recovered, possibly also in dispersion, are brought together and further treated in common. First, iron and heavy metals such as lead and zinc are separated in stepwise hydroxide precipitation. The iron compounds precipitated from the first stage of precipitation are returned more advantageously to the high temperature reactor, and are melted and separated as a usable metal granulate. The mixed precipitations of the subsequent precipitation stages contain the other metals and, processed in a concentrate, they are a usable material capable of melting. The solution flowing from the hydroxide precipitations contains predominantly alkali chlorides. The residual portion of calcium ions is precipitated by the introduction of carbon dioxide as calcium carbonate and likewise it is returned to the high temperature reactor to melt. The disruptive calcium ions still remain, which are present in a small proportion, and which could contaminate the usable salt of alkaline chloride, are removed in an ion exchanger. The alkaline chloride solution cleaned in this way is concentrated. For this purpose, the solution is subjected, more advantageously, to reverse osmosis. Finally, a mixed salt for use as raw or untreated material is obtained in a crystallization evaporator and a condensate is obtained, which can optionally be used as operating water. Therefore, by means of the method according to the invention, both the use of material of all gases, vapors and dust leaving the high temperature reactor and also the total release of waste water is guaranteed. Preferably, a device used to carry out the method according to the invention, according to claims 1 to 10, comprises a flow path for the synthesis gas, a recovery path for the converted usable materials and devices return to the high temperature reactor and to the conversion stages. In this regard, the flow path for the synthesis gas comprises at least subsequent steps in the treatment for: shock cooling with a pH value of < 5, neutralization with a pH value of > 8 and a combination converter, which, if necessary, includes additional wet treatment steps for conversion into usable recoverable materials, a powder wash with glycerin, a wash with Sulferox and a cold cooling step. The combination converter is then followed by a gas heating system and an activated carbon filter. In the indicated sequence, the crude synthesis gas flows through the flow path of the device and emerges as a synthesis gas of high purity usable thermally and / or materially. The recovery path, which serves to recover the converted usable materials, comprises at least the reaction stages: precipitation by hydroxide for iron, precipitation by hydroxide for other heavy metals, precipitation by carbon dioxide and ion exchanger for calcium, reverse osmosis and crystallization by evaporation, through which the water loaded with usable materials comes from the phases of shock cooling in common through the stages of neutralization and conversion, after which it has been collected and goes on the path of recovery by means of the first precipitation with hydroxide. The respective reaction stages of the recovery path have separation devices for usable materials such as sulfur, heavy metal hydroxides, usable salts and usable gases, and return devices to the high temperature reactor for the separated iron hydroxide and the washing powders with glycerin. The process water that remains after the recovery of usable materials is available as raw material water for optional use. By means of a thermal coupling between shock cooling, gas temperature equalization, cold drying and temperature equalization of the conversion stages, the total efficiency of the device can be improved, and for this purpose it can have the corresponding heat exchangers, and if necessary also heat pumps. The invention will be described in greater detail with reference to the figure.

In this figure, the number 1 indicates the high temperature reactor, which is described, for example in P41 30 416, is operated as a fusion reactor and has the outputs 19 and 20 for Fe and its metal alloys and minerals which have become inert, and the gas outlet 22 for the crude synthesis gas, which is passed to the spray cooler 2. In this spray cooler 2, which operates in the pH range < 5, that is to say, in the acid interval, the conversion of the ingredients begins, especially Cl, Pb, Zn and Fe transported along it. Simultaneously, the shock-like re-cooling of the crude synthesis gas takes place in order to prevent the formation of toxic organic materials (dioxins, furans) again. Subsequently, the crude synthesis gas is passed to the neutralization bath 3 which, at a pH value of > 8, neutralizes the moisture of the raw gas. The pH value conditions in the spray cooler 2 and in the neutralization valley 3 are coordinated with each other; they are measured and adapted continuously, which is more appropriate. After any necessary heating 6 'of the renewed gas, the heating which is predetermined by reactor conditions of the mixed conversion stage, the crude synthesis gas passes to the combination converter 4, which, in addition to one or a plurality of stages of conversion, have a glycerin wash for dust removal, a Sulferox stage for catalytic separation of sulfur and a stage for cooling drying. Sulfur, in a form usable as a useful material, is separated through outlet 16 directly from the Sulferox stage which operates separately from other conversion stages (moisture). The washing with glycerin has the outlet 8 for separate powders, by means of which the powders can be loaded with adsorbent harmful materials, and are returned for the renewed treatment at high temperature in the reactor 1. After drying by cooling, the crude synthesis gas is heated (heating 6"), and after passing through the activated carbon filter, leaves the device through outlet 18 as a high purity synthesis gas.A preferred embodiment herein proposes to house the activated carbon filter in interchangeable cassettes through which the gas can flow, in this way, a simple exchange is possible, and the return of the activated carbon to the high temperature reactor.The cassette can then be reused. (cold cooling 6.6 ', 6") located in the flow path described in this way are thermally coupled with the help of suitable elements such as heat exchangers and heat pumps, and are symbolized by the number 16 and arrows with direction. The process water from the spray cooler 2, the neutralization 3 and the combination converter 4 is collected and passed through the pipe system 7 to the first precipitation 9 with hydroxide. The iron hydroxide separated here is returned via outlet 15 to high temperature reactor 1 and melted. Subsequently, the collected processed water passes through a second precipitation with hydroxide, in which the lead and zinc hydroxides are precipitated in common, and are separated through the outlet 21 as a mixture. This mixture is known in the technology and is usable as a raw and useful material capable of melting. As a supplement to the method described, it is also possible, after the second hydroxide precipitation, to intercalate an additional precipitation with CO2 and to precipitate out any calcium ion present. Subsequently, the process water contains mainly sodium and potassium chlorides, which are a usable material that can only be slightly contaminated with calcium. These calcium impurities are removed in the ion exchanger 11 and the alkali chlorides are concentrated in step 12 by reverse osmosis, before they are obtained as a salt usable in the evaporator 13 by crystallization and separated through Output 17. Process water in this way is released from its ingredients and can optionally be used, along with the condensate from the cold dryer as operational water. The process is free of waste water. The figure shows that when the idea of the invention is used, the waste gasification is not only free of emissions of toxic materials, but it can also be carried out with total use of the energy and materials contained in the waste, without Waste material that is downloadable and without environmental stress due to wastewater is present. By means of the method of recycling at high temperature proposed here, the waste of various origins and compositions are completely transformed into reusable materials, that is, in: mineral granulate, iron metal alloy, synthesis gas, - elemental sulfur distilled water, a mixture of salts capable of electrolysis, and zinc and lead concentrate.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, the content is claimed as property in the following:

Claims (14)

1. A method for the total utilization of emission-free material of all community waste components or industrial waste by recycling or reuse at high temperature and by specific fractional conversion of resulting raw synthesis gas material, the method is characterized by less the following stages of process: conversion in stages of the materials contained as harmful materials in the raw synthesis gas into a valuable material, in separately heated, separated wet treatment stages, the temperature conditions of each treatment stage are predetermined by the condensation of the stage, necessary for the partial separation, of the water vapor contained in the crude synthesis gas, joining the solutions and condensates containing the converted useful materials of the different stages of conversion and the separation into stages of the Useful materials recoverable by precipitation n in stages and ion exchange reactions and separation reactions, with recovery of the process water, drying by cooling the synthesis gas cleaned by conversion of harmful materials, and returning the recovered process water together with the condensate from the cooling drying to the individual conversion stages.

2. The method according to claim 1, characterized in that at least one separately operable separation stage is placed, which acts catalytically in the flow path of the crude synthesis gas.

3. The method according to claim 1, characterized in that the shock cooling step is in the form of spray cooling and is operated in a pH range of < 5 to convert hydrogen chloride and heavy metals into recoverable chlorides.

. The method according to claims 1 and 3, characterized in that after cooling, which is adjusted to be acid, the residual moisture of the crude synthesis gas is located by a wet treatment step which is adjusted to be basic, and the crude synthesis gas is adjusted to a temperature optimal for the subsequent specific conversion stages.

5. The method according to claims 1 to 4, characterized in that a plurality of conversion stages placed in a common but subdivided container are used, and in which the crude synthesis gas flows through this "combination converter" to a approximately constant temperature.

6. The method according to claim 1 to 5, characterized in that within the "combination converter" a separation step of particles is operated with a separate circuit, if necessary, of the additive used, and the separated particles are returned to the reaction of degassing.

7. The method according to claim 1 to 5, characterized in that the iron and other heavy metals such as for example zinc and lead, are recovered in succession from the combined and condensed solutions of the cooling and conversion stages in at least Two stages of precipitation with hydroxide, the precipitated iron compounds are returned to the high temperature reactor, melted there and separated as a metallic granulate, while the hydroxides of the other heavy metals are processed as a concentrate capable of melting and are used directly as a raw or useful material.

8. The method according to at least one of claims 1 to 7, characterized in that the solution, which predominantly contains alkali chlorides, which flows from the precipitations with hydroxide, is released from contaminating calcium ions in an ion exchanger.

9. The method according to at least one of claims 1 to 8, characterized in that the purified alkaline chloride solution flows from the heat exchanger according to claim 8 and is concentrated by reverse osmosis, and then obtained from it in a crystallization evaporator a mixed salt of value as raw material, and a value condensate as process water.

10. The method according to at least one of claims 1 to 9, characterized in that associated with the shock cooler is a heat recuperator, and in which the heat recovered in this way is used by at least partially for temperature equalization of the synthesis gas and the conversion stages in the combination converter, and if necessary, for heating the gas in the front part of an activated carbon filter.

11. A device for carrying out the method according to at least one of the claims 1 to 10, characterized in that it has a flow path for the gas which contains at least the following active stages for the wet treatment: shock cooling with a pH value of < 5, neutralization with a pH value of > 8, and - a combination converter which integrally contains at least one converter stage for hazardous materials, a glycerin wash, a Sulferox wash and a cooling drying stage, and a gas heating system, and a activated carbon filter in the sequence indicated, which also has a recovery path which contains at least the following reaction steps: - precipitation for iron by hydroxide, precipitation for heavy metals by hydroxide, ion exchange for calcium, reverse osmosis, and crystallization by evaporation, through which the water loaded with the materials passes from shock cooling and neutralization and conversion in the indicated sequence, the reaction stages they have separation devices for water with useful materials, usable gas, usable salt, sulfur, heavy metal hydroxides, iron and minerals, and return devices for iron hydroxide and carbon to the high temperature reactor.

12. The device according to claim 11, characterized in that a gas temperature equalization system is placed in the flow path of the synthesis gas between the neutralization and the combination converter.

13. The device according to claim 11 or 12, characterized in that the shock cooling includes a heat recovery system which is at least partially coupled with the gas heating, the gas temperature equalization system and the cooling drying .

14. The device according to at least one of claims 11 to 13, characterized in that in the succession is placed a feeding device, a degassing channel and a high temperature reactor, the high temperature reactor, the latter has an opening of removal for melts and a removal opening for the synthesis gas, after which a gas cleaning device is incorporated.