SE185505C1

SE185505C1 -

Info

Publication number: SE185505C1
Authority: SE
Publication date: 1963-01-01

Description

Uppfinnare: H-L Schwechheimer, E Lobbeeke, 0 Hornung och E R Becker Prioritet begard fran den 28 december 1953 oat den 20 januari 1954 (Forbandsrepubliken Tgskland) Uppfinningen. har avseende pa en kupolugnsanlaggning, som drives med het blasterluft och vid vilken heta gaser fran kupolugnen atminstone till en del uttagas under dysplanet. Inventors: H-L Schwechheimer, E Lobbeeke, 0 Hornung and E R Becker Priority requested from 28 December 1953 to 20 January 1954 (Federal Republic of Germany) Invention. refers to a dome furnace plant which is operated with hot blaster air and in which hot gases from the dome furnace are at least partly taken out below the nozzle plane.

Man liar redan foreslagit kupolugnar, som drivas med het blasterluft och fran vilka heta gaser avdragas under dysplanet, vilka gasers inneboende varme kan anvandas for att upphetta blasterluften. It has already been proposed dome furnaces, which are operated with hot blaster air and from which hot gases are extracted under the dysplane, which gases' inherent heat can be used to heat the blaster air.

Foreliggande uppfinning har nu till andamai att fa fram forbattringar i avseende drivsattet, varmeabnyttjandet och ökning av det metallurgiska anvandningsomradet genom andamalsenlig utformning av dylika anlaggningar. The present invention now has for its object to obtain improvements with respect to the propulsion system, heat utilization and increase of the metallurgical field of application by spiritually appropriate design of such plants.

Narmast ligger uppfinningen i att kupolugnen under beskiekningsnivan och ovanfor smaltzonen har ett eller flera ytterligare gasuttag, vilka likaledes are anslutna till .efterforbranningskammaren. The closest invention lies in that the dome furnace below the charge level and above the melting zone has one or more additional gas outlets, which are likewise connected to the afterburning chamber.

Fare ugnen anordnas darvid lampligen en forhard, i vilken saval det flytande jarnet som de fran ugnen avdragna heta gaserna inledas. Eftersom jarnet godtyckligt kan uttagas fran forharden, är det majligt att kontinuerligt bortfara detsamma fran ugnen till f'orharden. Ur forharden sjalv flyter nu a ena sidan det flytande jarnet antingen kontinuerligt eller med intervaller, medan de heta gaserna kunna avga fran forhardens ovre del och ledas till en kammare, dar efterforbranning sker i andamal aft frigora det i gaserna eventuellt annu kvarvarande latenta varmet. Det är hi. a. andamalsenligt att redan i farharden foreta ga en delfarbranning av gaserna, varigenom man a ena sidan nar en extra temperaturokning och a andra sidan med sakerhet erhaller en reclueerande atmosfar i forharden. Dessutom kan man i den forharden efterkopplade kammaren leda in gaser, vilka bortledas frail omradet ovarrfor smaltzonen eller ovanfor beskickningen och som samtidigt efterforbrannas i denna forhrannings—eller stralningskammare. Saval forharden som forbrannings- eller stralningskamrarna kunna forces med luftuppvarrnningselement, vilka tj dna till uppvarmning av kalluft eller fill ytterligare upphettning av redan forvarmd luft. Dessutom kan stralningskammaren utrustas med angeller varmvattenalstringselement. I gaskanalen bakom stralningskammaren kan man vi-dare anordna en eller flera varmevaxlare luft- eller vattenforvarmning eller angalstring. The furnace is then suitably provided with a pre-hardener, in which the liquid iron as well as the hot gases withdrawn from the furnace is initiated. Since the iron can be arbitrarily removed from the furnace, it is possible to continuously remove the same from the furnace to the furnace. From the forearm itself, on the one hand, the liquid iron flows either continuously or at intervals, while the hot gases can emit from the upper part of the forearm and be led to a chamber, where post-combustion takes place and release any remaining latent heat in the gases. It's hi. a. it is essential to carry out a partial combustion of the gases already in the forehearth, whereby on the one hand an extra temperature increase is achieved and on the other hand a recuperating atmosphere is certainly obtained in the forehearth. In addition, gases which are discharged from the area above the melting zone or above the embryo can be introduced into the pre-cured chamber which is discharged from the area and which is at the same time post-burned in this pre-combustion or radiation chamber. Saval furnaces such as the combustion or radiation chambers can be powered by air heating elements, which serve to heat cold air or further heat already preheated air. In addition, the radiation chamber can be equipped with angler hot water generating elements. In the gas duct behind the radiation chamber, one or more heat exchangers can further arrange air or water preheating or angling.

En speciellt fordelakfig losning eras om man saramankopplar ett batten i av tvâ eller flera kupolugnar med en gemensam forhard och en gemensam stralningskammare och varmevaxlareanlaggning. A particularly advantageous solution is obtained if a batten of two or more dome stoves is connected together with a common forehearth and a common radiation chamber and heat exchanger system.

Enligt uppfinningen ernas framst ett battre utnyttj ande icke blott av det i gaserna förefintliga fria varmet utan aven av det latenta varmet. Man kan darvid aven anordna den angivna anlaggningen pa sadant satt, att den fran kupolugnen eller fran farharclen avdragna gasen forst ledes genom en varmevaxlare och forst efter denna varmevaxlare en for-. branningskammare inkopplas, i vilken .gasernas latenta varme frigares, samt gasen darafter ledes genom en andra varmevaxlare, i 2— — vilken varmet helt och hallet kan utnytti as. Harvid films ater den mojligheten att alstra den for kupolugnens drift erforderliga biasterluften sival i den Torsta som i den andra varmevaxlaren. DA emeltertid darutover ett vasentligt varmeoverskott fortfarande forefinnes, foreslas att i den forsta eller den andra eller i bada varmevaxlarna inbygga tillsatselement for alstring av het tryckluft, varmvatten eller Anga. Alstring av het tryckluft pa detta satt har den speciella fordelen, att den pa eft varmeekonomiskt gynnsamt salt kan utnyttjas i en varmluftsturbin. According to the present invention, a better utilization not only of the free heat present in the gases but also of the latent heat. It is then also possible to arrange the specified installation in such a way that the gas withdrawn from the dome furnace or from the vessel is first passed through a heat exchanger and only after this heat exchanger a furnace. combustion chambers are connected, in which the latent heat of the gases is released, and the gas is then passed through a second heat exchanger, in which the heat and the whole can be utilized. Harvid films again offer the possibility of generating the biaster air sival required for the operation of the dome furnace in the Torsta as in the other heat exchanger. However, in addition to the fact that a substantial excess of heat is still present, it is proposed to incorporate in the first or the second or in both the heat exchangers additional elements for generating hot compressed air, hot water or Anga. Generating hot compressed air in this way has the special advantage that it can be used in a hot air turbine for economically favorable salt.

Samlidigt kvarstar mojligheten att i forbranningskammaren, son]: är anordnad mellan de bada va..rmevaxlarna, inleda de fran kupolugnen uppstigande gaserna, sà att aven det i dessa forefintliga varmet utnyttjas. At the same time, the possibility remains that in the combustion chamber, which is arranged between the two heat exchangers, the gases rising from the dome furnace are initiated, so that also the heat present in them is utilized.

Vidare finnes mojlighet att genomfora ett sarskilt .fordelaktigt forfarande for anlaggningens drift, speciellt nar kupolugnen delvis anvandes for malmreduktion. Detta fOrfarande bestar vasentligen av foljande atgarder: Ugnens beskickning sker med en blandning av maim och skrot och maim, slagg, sinterprodukter och liknande saval som branslen av olika slag t. ex. kol, lampligen i lika stora stycken. Av det Iran smaltzonen :uppstigande varmet kommer det i schaktet befintliga branslet att forkoksas, varvid samtidigt en vittgdende reduktion av malmen ager rum. Denna forreducerade maim kommer att smaltas och uppkolas av den i smaltzonen fOrbrãnda torrdestillerade koksen, sâ att eft anvandbart jam kan framstallas i :ugnen. Genom att forbranningsgaserna bortledas under dysplanet kan en averhettning av det i smaltzonen smalta: jamet ernas. Furthermore, it is possible to carry out a particularly advantageous procedure for the operation of the plant, especially when the dome furnace is partly used for ore reduction. This procedure essentially consists of the following procedures: The kiln is loaded with a mixture of maim and scrap and maim, slag, sinter products and similar salvage as the industry of various kinds, e.g. coal, suitably in equal pieces. Of the Iran smelting zone: the rising heat, the industry in the shaft will be coked, at the same time a far-reaching reduction of the ore will take place. This pre-reduced maim will be melted and charred by the dry-distilled coke burned in the smelting zone, so that after usable jam can be produced in the oven. By dissipating the combustion gases below the dysplane, a overheating of the melt in the melting zone can be reduced.

Sarskilt vid mindre anlaggningar och sa(Tana, vid vilka ett flertal varmevaxlare icke aro .erforderliga :eller andamalsenliga, är en enkel uppbyggnad av anlaggningen av sarskild betydelse. For sadana fall ar .enligt uppfinningen en forenklad utforingsform forsedd. Harvid har man narmast utgatt fran det faktum, att det en liten bit under smaltzonen i ugnen radande overtrycket manga ganger om är tillrdckligt fOr att trycka gaserna genom en rekuperativ varmevaxlare utan att det är nodvandigt aft anordna en sugflakt. Stromningsnaotstdndet i rekuperatorn ãr under normala forhallanden sa litet relativt det, som de genom beskickningsgodset i ugnen uppat strommande gaserna moter, att en vasentlig gasvolym soker sig vag genom den med mind-re motstand belastade rekuperatorn. Genom att Oka eller minska stromningsmotstandet genom rekuperatorn och gasuttagsiippningen bar man i sin hand att anpassa den genom rekuperatorn strommande gas- och varmemangden efter varmebeb.ovet for den hilt, coin skall uppvarmas. Man kan uttaga gaserna fran kupolugnen genom en eller flera oppningar, vilka kunna anbringas direkt under dysorna el ler forskjutna relativt dessa. En speciellt enkel utfaringsform erbjudes om man anvander uttaget for jam och slagg aven for bortledning av gaserna. Especially in the case of smaller plants and so on (Tana, in which a number of heat exchangers are not required: or otherwise), a simple construction of the plant is of special importance. In such cases, according to the invention, a simplified embodiment is provided. the fact that the overpressure radiating a small distance below the melting zone in the furnace is often sufficient to push the gases through a recuperative heat exchanger without the need to provide a suction flap. the gases flowing through the cargo in the furnace cause a substantial volume of gas to seep through the lesser-loaded recuperator. and the amount of heat after the heatbeb.ovet for the hilt, coin shall u ppvarmas. The gases can be taken out of the dome furnace through one or more openings, which can be fitted directly under the nozzles or offset relative thereto. A particularly simple embodiment is offered if the outlet for jam and slag is also used for discharging the gases.

Rekuperatorns utloppsoppning kan man enklare ansluta till stralningskammaren eller till kupolugnens schakt. Man kan aven 'Ater infora de fran rekuperatorn avgdende gaserna i den ovre delen av ugnens beskickningspelare. The recuperator's outlet opening can be more easily connected to the radiation chamber or to the shaft of the dome furnace. You can also re-insert the gases from the recuperator into the upper part of the oven's pillar.

Onskar man tillampa uppfinningen vid en redan forhandenvarande kupolugn, -vid vilken rekuperatorn tillfOres gaser, vilka uttagas fran ugnen ovanfor beskickningen eller Iran nagot stalle ovanfor smaltzonen, med eller utan efterforbranning, kan en omstallning av en dylik anlaggning latt genomforas genom att man under dysplanet anbringar en eller nem uttagsoppningar pa ugnen och leder gasen harifran till rekuperatorn. Dessa gaser genomstromma darefter rekuperatorn tillsammans med de fran andra stallen av ugnen bortgaende gaserna. Vid aldre anlaggningar uppstar ofta i ugnens byre del en icke onskyard flamma, som exempelvis vid anvandning av centralbeskickningsskopor skadar dessa. Vid dylika anlaggningar kan man .genom att efterat anbringa anordningen enligt uppfinningen elirninera denna flamma pa ett enkelt satt, varvid anlaggningen lampligen kan drives med ett lagre htfttryck an vad som är vanligt vid hittills kanda anlaggningar. If it is desired to apply the invention to an already existing dome furnace, in which the recuperator is supplied with gases, which are taken from the furnace above the embankment or Iran somewhat above the smelting zone, with or without afterburning, a conversion of such a plant can be carried out by placing under the dysplane one or two outlet openings on the furnace and directs the gas from there to the recuperator. These gases then flow through the recuperator together with the gases leaving the other stalls of the furnace. In the case of older plants, a non-cloudy flame often arises in the outer part of the furnace, which, for example when using central loading buckets, damages them. In the case of such plants, by subsequently applying the device according to the invention, this flame can be eliminated in a simple manner, whereby the plant can suitably be operated with a lower heat pressure than is usual in hitherto known plants.

Lufttrycket kan alltefter ugnens storlek variera mellan 200 och 300 mm vattenpelare. The air pressure can vary between 200 and 300 mm water columns depending on the size of the oven.

Pet ãr tydligt, att uppfinningen liven ken tillampas om pa vanligt satt en .gemensam rekuperator är anordnad for flera ugnar. It is clear that the invention can be applied to the life if, in the usual way, a common recuperator is arranged for several furnaces.

Pet kan under vissa omstandigheter vara fOrdelaktigt att vid en ytterligare utveckling av anordningen enligt uppfinningen icke inblasa luften centralt i ugnen, .utan anordna dysoma fOr tangentiell inblasning av luften eller ge dysorna en riktning mellan ett centralt och tangentiellt lage. Harvid är det i vissa fall lampligt, med tanke pa smaltzonens utbredning, att icke anordna dysorna horisontellt, utan snett uppatriktade. In certain circumstances it may be advantageous in a further development of the device according to the invention not to blow the air centrally into the oven, but to arrange the nozzles for tangential blowing of the air or to give the nozzles a direction between a central and tangential layer. In this case, it is in some cases appropriate, in view of the extent of the narrowing zone, not to arrange the nozzles horizontally, but to be oriented obliquely.

Vidare am det aven har mojligt att 1 gastillforselledningen till rekuperatorn anordna en efterforbrannings_ eller stoftavskiljningskammare, som lampligen är cyklonformigt utbildad. I denna kammare kan man samtidigt in-fora friskluft for att saval genomfora en efterforbranning av i gaserna eventuellt forefintliga brannbara bestandsdelar som installa de rekuperatorn tillstrommande gaserna pa lamplig temperatur. Om derma temperaturreglering icke skall astadkommas medelst friskluft, kan man exempelvis anvanda en liten flakt, som suger rokgasen Iran exempelvis skorstenen. Furthermore, it is also possible for the gas supply line to the recuperator to provide a post-combustion or dust separation chamber, which is suitably cyclone-shaped. At the same time, fresh air can be introduced into this chamber in order to carry out a post-combustion of any combustible constituents present in the gases which install the gases flowing into the recuperator at a suitable temperature. If this temperature control is not to be achieved by means of fresh air, one can, for example, use a small flake, which sucks the flue gas Iran, for example the chimney.

Pa ritningen visas olika utforingsexempel schematiskt. Fig. 1 visar en kupolugnanlaggning enligt -uppfinningen med forha.rd, stral- — —3 ningskammare och en extra varmevaxlare fran sidan. Fig. 2 visar i planvy en aniaggning, vid vilken tre kupolugnar aro kombinerade med en gemensam forhard med stralningskammare och en tillsatsvarmevaxlare. Fig. 3 visar en annan utforingsform, speciellt betraffande kopplingen av varmevaxlaren och forbranningskammaren, dock utan forhard. The drawing shows various embodiments schematically. Fig. 1 shows a dome furnace installation according to the invention with a preheated, radiating chamber and an additional heat exchanger from the side. Fig. 2 shows in plan view an arrangement in which three dome stoves are combined with a common front hearth with radiation chamber and an auxiliary heat exchanger. Fig. 3 shows another embodiment, in particular concerning the coupling of the heat exchanger and the combustion chamber, but without a pre-hardener.

I utforingsformen enligt fig. 1 och 2 uttages det flytande jarnet och de heta gaserna fran kupolugnen 1 under smaltzonen och ledas genom ledningen 2 till forharden 3. Slaggen kan antingen avtappas genom ledningen 2 eller genom ett sarskilt slagghal. Genom rannan 4 uttages det flytande jarnet Fran forharden 3. Ovanfor forharden 3 befinner sig den som stralningskammare utbildade forbranningskammaren 5, i vilken aro inbyggda varmeupptagande element 6, vilka kunna vara utforda som luftforvarmare eller som varmvatten-, angbildnings- eller angoverhettningselement. I stralningskammaren 5 inkommer genom forbindelsen 7 de heta gaserna fran for-harden 8. Dessutom kan i forbranningskammaren 5 genom ledningen 8 over tillsatsugnen inforas heta gaser, vilka uttagas frail kupolugnen nagonstans i omradet ever dysplanet. Genom ledningen 9 inkomma gaserna frail forbranningskammaren i varmevaxlaren 10, vilken det i gaserna annu kvarvarande varmet utnyttjas for uppvarmning av luft eller vatten eller for angalstring. Sugflakten 11 transporterar de genom anlaggningen strommande gaserna -via skorstenen 12 till det fria. Dessutom ar en ledning 13 anordnad, genom vilken gaserna fran skorstenen kunna ledas tillbaka till forbindelseledningen mellan stralningskammaren och varmevalaren 10. Kallluft tillfOres varmevaxlaren 10 genom ledningen 14, lamnar densamma genom ledningen 15 och inkommer i kupolugnens blasterluftning 16 genom ledningen 17. Den i varmevaxlaren 10 uppvarmda luften kan ytterligare upphettas i elementen 6, om man hellover sarskilt hog temperat-ur hos kupolugnens blasterluft. In the embodiment according to Figs. 1 and 2, the liquid iron and the hot gases are taken from the dome furnace 1 below the melting zone and passed through the conduit 2 to the front hardener 3. The slag can either be drained through the conduit 2 or through a special slag hall. Through the gutter 4 the liquid iron is removed from the preheater 3. Above the preheater 3 is the combustion chamber 5 formed as a radiation chamber, in which are built-in heat-absorbing elements 6, which can be challenged as air preheaters or as hot water, steam or steam heating elements. In the radiating chamber 5, the hot gases from the pre-hearth 8 enter through the connection 7. Through the line 9, the gases from the combustion chamber enter the heat exchanger 10, which the heat still remaining in the gases is used for heating air or water or for fuel generation. The suction surface 11 transports the gases flowing through the plant - via the chimney 12 to the open air. In addition, a conduit 13 is provided, through which the gases from the chimney can be conducted back to the connecting conduit between the radiation chamber and the heat exchanger 10. Cold air is supplied to the heat exchanger 10 through the conduit 14, leaves it through the conduit 15 and enters the dome furnace blaster aeration 16 through the conduit 17. the heated air can be further heated in the elements 6, if the temperature of the dome oven's blaster air is particularly high.

Kupolugnen kan darjamte i smaltzonen utrustas med kylelement 18, vilka lampligen anvandas som angalstrande element, sa. att den erforderliga kylvattenmangden halles liten. Genom installning av det tryck, vid vilket dessa element drivas, kan man halla den i kylelementen radande temperaturen konstant vid bestamda varden. The dome furnace can also be equipped in the melting zone with cooling elements 18, which are suitably used as angling elements, sa. that the required amount of cooling water is kept small. By installing the pressure at which these elements are operated, the temperature radiating in the cooling elements can be kept constant at a certain value.

Enligt fig. 2 aro tie kupolugnar 1 anordnade omkring den gemensamma forharden 3, fran vilken de heta gaserna ledas till den gemensamma fOrbranningskammaren 5, varifran de i sin tur ledas till varmevaxlaren 10. Forbranningskammaren 5 kan utrustas med en tillsatsbrannanordning 19, som anvandes om varmet i de fran farharden och eventuellt genom ledningen 8 1 stralningskamm.aren intradande gaserna icke racker for att upphet ta blasterluft, varmvatten eller anga till onskad temperatur eller i onskad mangd. According to Fig. 2, there are cupola furnaces 1 arranged around the common pre-hearth 3, from which the hot gases are led to the common combustion chamber 5, from which they in turn are led to the heat exchanger 10. The combustion chamber 5 can be equipped with an additional combustion device 19, which is used for the heat in the gases entering from the vessel and possibly through the line 8 in the radiation chamber, the gases do not reach to heat blast air, hot water or enter the desired temperature or in the desired amount.

I fOrharden 3 kunna ,aven lake visade element inbyggas for alstring av blasterluft eller anga, vilka element samtidigt tjana till att forbattra hallbarheten hos forhardens stral, ningsvalv. Elements, also shown in the lake, can be built into the curtain 3 for the production of blaster air or steam, which elements at the same time serve to improve the durability of the curtain's radiating vault.

En speciell fordel hos anlaggningen enligt uppfinningen ligger i att den arbetar sarskilt ekonomiskt och att man genom att anvanda densamma far ett sarsldlt start spelrum i fraga om arten av det i kupolugnen anvanda rdmaterialet. A special advantage of the plant according to the invention lies in the fact that it works particularly economically and that by using it one gets a special starting clearance as to the nature of the raw material used in the dome furnace.

I utf5ringsformen enligt fig. 3 tillfores kupolugnen 1 blasterluft genoni dysorna 20, vilka lampligen aro riktade snett uppat, men aven kunna vara riktade horisontellt eller snett bakat. De heta gaserna uttagas genom ledningen 21, som sammanbinder kupolugnens nedre del med varmevaxlaren 22. Sedan gaserna genomstrommat varmevaxlaren, inkomma de i forbranningskammaren 23, som samtidigt tillfores tillsatsforbranningsluft genom ledningen 24, vilken luft kan vara forvarmd. Genom ledningen 25 kunna de i kupolugnens schakt uppstigande gaserna, eventuellt med hj alp av en flakt, tillforas forbranningskammaren 23. Flakten utbildas lampligen son" en stralpump, sa att forbranningsluften, vilken anyandes som drivluft, infores samtidigt med de frail kupolugnens ovre del bortsugna gaserna i forbranningskammaren 23. In the embodiment according to Fig. 3, the dome oven 1 is supplied with blaster air through the nozzles 20, which are suitably directed obliquely upwards, but can also be directed horizontally or obliquely backwards. The hot gases are extracted through line 21, which connects the lower part of the dome furnace to the heat exchanger 22. After the gases have passed through the heat exchanger, they enter the combustion chamber 23, which is simultaneously supplied with additional combustion air through line 24, which air may be preheated. Through the line 25, the gases rising in the shaft of the dome furnace, possibly with the aid of a flake, can be supplied to the combustion chamber 23. The flake is suitably formed as a jet pump, so that the combustion air, which otherwise acts as propellant air, in the combustion chamber 23.

Sedan gasernas latenta varme frigjorts i forbranningskammaren 23, ledas gaserna in I den andra varmevalaren 26. I utforingsexemplet anvandes yarmeyOxlaren. 22 for att alstra blasterluften for kupolugnsdriften, medan varmevaxlaren 26 alstrar het tryckluft, varmvatten eller anga. Man kan aven uppdela uppvarmningsytorna mellan de bada varmevaxlarna pa annat satt eller i annat forhallande. I en del fall kan det yam lampligt att utforma varmevaxlaren 22 som Overhettare fi5r tryckluft eller blasterluft eller den eventuellt alstrade angan. Kupolugnens smaltzon forses lampligen oven har medvatten- eller angkylda kylelement. After the latent heat of the gases is released in the combustion chamber 23, the gases are introduced into the second heat exchanger 26. In the exemplary embodiment, the heat exchanger is used. 22 to generate the blaster air for dome furnace operation, while the heat exchanger 26 generates hot compressed air, hot water or steam. You can also divide the heating surfaces between the two heat exchangers in another way or in a different condition. In some cases, it may be appropriate to design the heat exchanger 22 as a superheater for compressed air or blaster air or any steam generated. The dome furnace's narrowing zone is conveniently supplied with oven-cooled or steam-cooled cooling elements.

Claims

Patentansprfi.k:

A dome furnace system operating with hot blaster air with a gas outlet arranged below the dysplane, from which the gas for utilizing its heat is led to a. afterburning chamber, characterized in that the dome furnace below the loading level and above the smelting zone has one or more additional gas outlets (8), which are likewise connected to the afterburning chamber (5).

Plant according to claim 1, wherein a part of the developed heat is used for heating the blaster air, characterized in that heat-absorbing elements (6) are built into the afterburning chamber (5).

Plant according to patent claim 1 or 2, characterized in that a pre-hearth (3) is arranged in the gas carriage between the cup oven (1) and the combustion chamber (5). Request publications: Patents from Sweden 45,661; Germany 417,921, 471,870.