JP3084168B2 - Maintenance method for continuously charged high temperature reactor - Google Patents

Abstract

A method for the maintenance of a high temperature reactor is described, in which a lower hearth part which is damaged as a consequence of mechanical, chemical and/or thermal stress and forms a structural unit with a molten bath hearth is exchanged for a back-up unit. Charging of the high-temperature reactor is firstly interrupted for this purpose. The molten liquid is withdrawn from the molten bath in the lower hearth part. The combined fuel burners, which are lead via cooling jackets through the hearth wall, are removed, and the connecting elements between the upper part and hearth part are loosened. The hot lower part is then removed from its operating position. The back-up unit, which has been heated in advance, is brought into the operating position, and the combined fuel burner is introduced together with the oxygen leads into the cooling jackets of the back-up unit. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a process for the production of carbon from the thermal conversion of organic waste components or other continuously supplied waste products, wherein the carbon is vaporized by oxygen and the inorganic components of these waste products are melted. The present invention relates to a method for maintaining a high-temperature reactor.

[0002]

2. Description of the Related Art A maintenance method for a high-temperature reactor requires labor and an extremely long time as well as a method for maintaining and repairing a blast furnace, a rotary kiln and the like. The high operating temperatures in such reactors require having the furnace thick lining with a suitable refractory material, such refractory material being formed from tamped material or, in the case of multiple linings, usually pre-formed. It may be formed in part from a manufactured refractory block. Cast or compacted linings as well as refractory block linings must be tempered for a long time before use. When shutting down a furnace that requires repair, it is necessary to wait a long time for the furnace to cool to an appropriate temperature. For example, rotary kilns used for the purpose of incinerating waste must be shut down or closed twice a year, in each case for six weeks, so that the damaged lining can be repaired as required.

[0003] The situation is the same for blast furnaces that produce molten metal or perform metallurgical processes. Shutdown-repair time for metal smelting furnaces required for long cooling and reheating times in the process of melting metal scrap, especially scrap iron or similar refractory charge in a shaft furnace operated without coke It is already known to lower the lower hearth of a furnace detachably mounted after suitable use by means of a hydraulic device in order to reduce it and to repair it separately from the furnace shaft (DE 37 42 349 Cl).
issue). Discontinuous charging takes place in such shaft furnaces. That is, the material is loaded into the top region of the furnace shaft using an airtight lid.

In this connection, there is provided a metal smelting furnace having a vertical furnace shaft and a lower hearth with a flange formed, the annular flange surface having a radius such that a particularly easily manageable flange connection exists. Reference is also made to a directionally drawn smelting furnace (U.S. Pat. No. 4,291,634).

[0005]

In this case, the carbon obtained by the heat conversion of the organic waste components is measured and vaporized by the added pure oxygen, and the inorganic components are melted and discharged in a molten state. Maintaining the lower part of the high temperature reactor is a problem. Preferably, the waste product is continuously fed through a pretreatment zone, such as a degassing duct, to the reactor floor, which is exposed to high temperatures and mechanical and chemical stresses and loads.

In this case, the waste product is unseparated, untreated, and partly continuously subjected to this thermal pretreatment as a liquid component and is forced in a compressed state through a duct for receiving it, Both liquid and volatile components are evaporated in a so-called "caking process". Domestic or special or industrial waste and waste materials thus pretreated are subjected to high temperature treatment in bulk in a high temperature reactor. This is, for example, as well described in the literature,
The disadvantages of the previously known waste incineration methods or the corresponding pyrolysis methods are avoided.

The advantage is a closed and therefore environmentally benign process technology, which can avoid the high air flow velocities that are necessarily present in the case of conventional incineration plants. In known melting processes intended for waste products that have been pyrolyzed beforehand in a high-temperature reactor, in this case the introduction takes place in the form of a compacted bed, but with sufficient gas permeability in the compacted bed. Despite the high energy costs, it has been found that, despite the high energy costs, the production of gas is inadequate and very long residence times occur in the reactor.

The continuous introduction of the substance to be melted into the high-temperature reactor in bulk avoids this problem. The high-temperature reactor to which the maintenance method according to the present invention is applied has a two-part structure, that is, an upper part and a lower part which can be separated from the upper part. That is, it has an upper stabilization zone for the resulting gas fraction and a hearth to which the bulk pretreated molten material is continuously supplied. The upper part and the lower part are securely interconnected by an airtight and tight flange connection. The high-temperature reactor is lined with refractory material in a manner known per se, the lining being such that it can withstand temperatures in the reactor of 1600-2000 ° C. In the furnace area below the formed loose floor, preferably several oxygen lances exit through the hearth lining, integral with the composite burner and supported by the cooling jacket. As a result of the cooling jacket of the oxygen lance penetrating the refractory material radially from outside to inside, a temperature gradient is formed in the contact area on the inner surface of the lining, at least of the material evaporated or liquefied by the oxygen burner. A wide variety of uncontrolled chemical reactions and fusion processes result because of the partial retrocondensation. After a brief operation of the high-temperature reactor, the cooling jacket of the composite burner with the oxygen supply pipe fuses very strongly with the refractory lining surrounding them, so that it is no longer possible to remove the cooling jacket without destroying the lining. It is possible. Since the cooling jacket only has one coolant supply line and one coolant discharge line, there are no problems associated with the connection of these to the reactor for repair, but the displacement in the cooling jacket Since the possible oxygen lances, i.e. the compound burners, are connected to a plurality of control connections, monitoring members, at least one auxiliary gas line, etc., their exchange is relatively complicated.

By supplying pure oxygen or oxygen-enriched air near the height of the composite burner in the gasification or melting zone of the high temperature reactor, the agglomerate bed is gasified by oxidation to the extent that it is constituted by a carbon fraction. While being mineralized, the inorganic and metallic components are melted and then flow in a molten state into a homogenizing reactor lined with a gasification zone, preferably lined. The homogenization reactor, by construction, forms a unit with the lower part of the high temperature reactor. As the melt clarifies in the homogenization reactor, there is a completely homogeneous molten bath of inorganic and / or metallic components. As a result of the particularly invasive chemical and mechanical action and high temperature values prevailing in the gasification zone of high temperature and homogenization reactors,
Since the refractory lining of the walls of said area causes a particularly high level of wear, the time during which the high temperature reactor can be used is limited by the necessary repairs or at least maintenance work.

The high reactor idle time which necessarily occurs in the prior art for the repair of linings of blast furnaces and high temperature reactors is acceptable in the case of intermittently charged cupola furnaces, etc. Alternatively, this idle time is unacceptable if the supply of the substance to be evaporated is continuous as a result of their pretreatment. In a waste treatment plant, waste is continuously supplied. It is not possible to store waste components that decompose due to decay, for example, in hot summer months in the plant supply area where the required six-week repair work is performed. The logistics that such problematic plants rely on must eliminate such idle times. There is a need to have alternative disposal means that can be used during several weeks of repair.

The object of the present invention is to make the parts which are heavily loaded after abrasion occur, especially for high-temperature reactors having the above-mentioned problems, to the required operating conditions much more than was previously possible. It is an object of the present invention to provide a maintenance method capable of recovering quickly and considerably reducing plant idle time.

[0012]

This object is achieved by a method according to the characterizing part of claim 1. That is, a high-temperature reactor in which carbon obtained by thermal conversion of organic waste components or other continuously supplied waste products is vaporized by oxygen and the inorganic components of these waste products are melted, a melting furnace and Lower part damaged by mechanical, chemical and / or thermal stress loading, flanged to a fixed upper part of said high temperature reactor operating as a homogenizing reactor, forming a structural unit with a molten bath hearth In a method for preserving the hearth by replacing it with a corresponding spare unit, the replacement comprises the following steps: (a) interrupting the charging to the high-temperature reactor only while replacing the lower hearth part; (b) The solids still present in the lower hearth section at the beginning of the charging interruption are completely vaporized and melted by the composite burner and the molten liquid is discharged from the molten bath; (c) cooling Removing from the cooling jacket a composite burner provided with a racket and with an oxygen supply pipe guided through the wall of the lower hearth section; (d) disconnecting the connecting element between the upper and lower hearth sections of the high temperature reactor (E) removing the hot lower hearth portion from its operating position; (f) a spare lower hearth portion preheated to immediately operate the high temperature reactor. Placing in an operating position and consolidating the upper part of the high temperature reactor in a compaction manner; (g) introducing and operating a composite burner with an oxygen supply pipe into the cooling jacket of the auxiliary unit in the lower hearth section (H) restarting charging into the high-temperature reactor; and (i) maintaining the lower hearth portion to be overhauled after sufficient cooling after removing from the operating position and maintaining the lower hearth portion. It is solved by a method carried out in the step of again available as a spare part after.

[0013] Such a high temperature reactor in which the material is continuously supplied to the reactor is subdivided into a fixed reactor section and a section which can be separated and removed therefrom, and this removable reactor section. Replacement within a short period of time and is independent of actual maintenance or repair work.
Important for the present invention. Such charging of the reactor need only be interrupted during the replacement of the separable parts of the reactor, the separation of this or similar parts and their replacement by the same new or repaired part. The time required does not depend on the actual maintenance and / or repair.

As soon as the charging to the reactor is interrupted for a scheduled replacement, the solids still present in the lower hearth are melted or gasified and the residual molten bath is drained off, the upper part of the high-temperature reactor is turned off. Separation of the flanges between the lower and lower parts can be initiated, simultaneously or immediately before or after the oxygen lances need to be interrupted from their cooling jacket to the various connections to the control, inspection, supply and removal units You can take it out without having to do it. The high-temperature reactor lower hearth forming the structural unit with the molten bath vessel is lowered slightly by a few millimeters with respect to the fixed upper part of the reactor and removed from its operating position. Simultaneously with this step, it is possible to carry the corresponding spare unit to the location of the high-temperature reactor and to mount it for flange connection on the upper part of the high-temperature reactor. It is necessary to heat the spare unit to a temperature close to the operating temperature, for example, 800 ° C. for a sufficient time in advance. This makes it possible to resume the charging of the reactor which was interrupted for a short time for replacement and repair work, immediately after the consolidation of the lower and upper parts has taken place. Since the oxygen supply pipe is introduced into the cooling jacket of the spare unit at the same time during the flange connection step, the operation of the oxygen supply pipe can be resumed immediately thereafter.

[0015] Then, the reactor lower part to be repaired, which is still at the high operating temperature, is cooled independently of the return of the plant to operation, once it has reached a temperature acceptable for repair,
It can be restored to a complete operating state again. Only when further repair is found to be necessary is the complete spare unit heated so that it can be acted upon immediately at the next quick replacement.

The idle and repair times required for a high temperature reactor or similar combustion or melting furnace, lasting several weeks, are reduced to a few hours as a result of the replacement process according to the invention, whereby the complete plant Quasi-continuous operation is guaranteed, productivity is increased, operation safety is improved,
The danger to the environment and the danger to the operator are eliminated.

──────────────────────────────────────────────────の Continued on front page (73) Patent holder 591035988 Meierhofstr. 2, FL-9490 Vaduz, Liechtenstein (56) References JP-A-4-227465 (JP, A) JP-A-62-263533 (JP, U) JP-A-4-64094 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) F23G 5/44 F23G 5/00 F27B 3/00-3/28

Claims (1)

(57) [Claims] 1. A high-temperature reactor in which carbon obtained by the thermal conversion of organic waste components or other continuously supplied waste products is vaporized by oxygen and the inorganic components of these waste products are melted. By mechanical, chemical and / or thermal stress loading, which is flanged to the fixed upper part of said high temperature reactor, which operates as a melting furnace and a homogenizing reactor, forming a structural unit with a melting bath hearth In a method for preserving a damaged lower hearth by replacing it with a corresponding spare unit, the replacement comprises the following steps: (a) interrupting charging to the high temperature reactor only while replacing the lower hearth portion; (B) completely vaporizing the solids still present in the lower hearth section at the beginning of the charging interruption by means of the composite burner, melting and discharging the molten liquid from the melting bath; Removing from the cooling jacket a composite burner with a cooling jacket and an oxygen supply pipe guided through the wall of the lower hearth section; (d) connecting the connecting element between the upper and lower hearth sections of the high temperature reactor. Removing and lowering the lower hearth portion slightly; (e) removing the hot lower hearth portion from its operating position; (f) a spare lower hearth pre-heated to immediately operate the high temperature reactor. Placing the section in the operating position and compactingly connecting it to the top of the high-temperature reactor; (g) introducing and operating a composite burner with oxygen feed pipe into the cooling jacket of the auxiliary unit in the lower hearth section (H) restarting charging into the high-temperature reactor; and (i) maintaining the lower hearth portion to be overhauled from the operating position after sufficient cooling to maintain the lower hearth portion. How to implement in the process of re available as spare parts after performing.