EP0048802B1 - Procédé de réglage de la qualité de coke - Google Patents

Procédé de réglage de la qualité de coke Download PDF

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Publication number
EP0048802B1
EP0048802B1 EP81105965A EP81105965A EP0048802B1 EP 0048802 B1 EP0048802 B1 EP 0048802B1 EP 81105965 A EP81105965 A EP 81105965A EP 81105965 A EP81105965 A EP 81105965A EP 0048802 B1 EP0048802 B1 EP 0048802B1
Authority
EP
European Patent Office
Prior art keywords
coal
coke
temperature
coking
oven
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81105965A
Other languages
German (de)
English (en)
Other versions
EP0048802A3 (en
EP0048802A2 (fr
Inventor
Gerd Dr.-Ing. Nashan
Wilhelm Dr.-Ing. Weskamp
Dr.-Ing. Stewen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RAG AG
Original Assignee
Ruhrkohle AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ruhrkohle AG filed Critical Ruhrkohle AG
Publication of EP0048802A2 publication Critical patent/EP0048802A2/fr
Publication of EP0048802A3 publication Critical patent/EP0048802A3/de
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Publication of EP0048802B1 publication Critical patent/EP0048802B1/fr
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C10B57/04—Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B47/00—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion
    • C10B47/02—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with stationary charge
    • C10B47/10—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with stationary charge in coke ovens of the chamber type

Definitions

  • the invention relates to a method for controlling the quality of coke from coal feed mixtures which are coked in the coke oven by indirect heating with the exclusion of air, the coal feed mixture undergoing plasticization during the coking process when passing through the temperature range of 320-550 ° C., which increases with the cooking time shifted from the furnace wall to the center of the furnace.
  • Mixtures are usually used for coking. I.e.
  • the coking coals are first ground in order to achieve certain different grain sizes.
  • the different grain sizes give a grain spectrum that significantly influences the bulk density of the coking coals in the coke oven. It has been shown that optimal grain spectra can usually only be achieved by mixing different ground grain sizes.
  • Baking capacity is also of major importance. Baking ability is understood to mean the ability of the coal to change to a plastic state when heated in a vessel which allows the coal to expand freely and to form a baked, lumpy coke when heated further. Coal with good baking power not only provides baked, but even melted coke.
  • the baking capacity defined in this way is measured either by the swelling index or by the Roga baking number.
  • a coal with a good baking capacity can still produce a less high-quality coke under the operational coking conditions than a poorly baking coal. Therefore, the coking capacity has to be considered in a special way.
  • the coking capacity of a coal is assessed either by the dilatometer test or by determining the Grayking coke type. To determine the course of dilation, the change in length of a conical carbon compact is measured at a heating rate of 0.05 ° C / sec.
  • the plastic behavior is understood as the ability of the coal to change into a plastic state within the temperature range between about 350 and 550 ° C.
  • Modified rotary viscometers are used in the usual methods for measuring plasticity.
  • the result of the measurement is not the viscosities of the softened coal mass in the physical sense, but quantities influenced by the apparatus, which are composed of the internal friction of the solid, liquid and gaseous phases and the elasticity variables of these three phases.
  • Such measurements are usually laboratory measurements. This also applies to measurements of the degassing behavior, the driving pressure and the shrinkage, which are also used to determine the quality of the coal used.
  • the large number of test methods commonly used here, which are commonly used in practice, for determining the amount of coal used and for determining the quality of coke shows that previously, targeted control of the quality of coking coal as the basis for high-quality coke was only possible with multiple measurements and particular difficulties.
  • the object of the invention is therefore to simplify the control of the required quality of the input material.
  • the invention is based on the consideration that essential parameters for the coke quality have a common effect in a partial area of the coking process. This is the plastic area in further knowledge, which becomes clear when considering the coking process of hard coal in indirectly heated horizontal chamber furnaces.
  • Coking produces heating gases that are burned in the heating trains adjacent to the ovens.
  • the heat is transferred from the neighboring heating trains through the furnace walls to the furnace lining, i.e. the insert coal mixture, transferred.
  • Due to the indirect heating on both sides temperature fields arise with a decreasing temperature level towards the center of the trim.
  • the temperature fields are usually symmetrical to the center of the furnace, where the lowest temperature prevails.
  • With increasing cooking time the temperature front progresses from the walls to the middle of the oven, accompanied by a steep temperature gradient during the transition from the already coked to the unchanged charcoal.
  • This transition area in which all temperatures of 100-1000 ° C are run through, is locally limited and at the beginning of the coking process (pyrolysis) only extends over a few mm in the mainly 450 mm wide furnace chamber.
  • the gradual coking of the home carbon takes place, whereby two essential temperature ranges can be distinguished.
  • One temperature range extends from about 320-480 ° C. In the temperature range, the coal softens and forms a quasi-plastic state. When through When the temperature range is exceeded, a large number of decomposition and polymerization reactions take place, creating the conditions for integrating inert components and pre-embossing the coke quality.
  • the other area is above the reconsolidation of the furnace stock with a contraction maximum around 600 ° C.
  • the coke structure is formed with further flavoring of the stock.
  • the reactions taking place in both areas are dependent on the type of coal used and the grain size of the feed components, but the invention is based on the fact that the type of coal and grain size are largely predetermined in normal coking plant operation and, for the respective coke quality, rather the dependence of the coking on the operating conditions and The focus is on the pretreatment of the feed or the use of coking agents. I.e. According to the invention, the extent and the uniformity of the reactions taking place in these critical transition areas is of crucial importance.
  • the temperature gradient is decisive for the course of these reactions.
  • a high temperature gradient means a high local heating rate at which the reactions taking place can only develop inadequately or, depending on their kinetics, are even overflowed. This leads to great inhomogeneity in the reaction process and results in an inhomogeneous coke structure.
  • the duration of the plasticity which correlates clearly with the heating rate i.e. decreasing with increasing heating rate is too short.
  • the diffusion paths for the released gases increase with increasing width of the plastic zone.
  • the gas pressure is maintained over a longer period of time, which can lead to greater homogeneity in the gas bubble distribution as in the previous generation and further reactions of gaseous decomposition products.
  • FR-A 752 468 refers to the plastic zone, but the temperature range of 650-750 ° C has been selected. This is the area of reconsolidation with a contraction maximum around 600 ° C. In this area, the coke structure is formed with further flavoring of the stock.
  • the reactions taking place in the plastic zone and in the post-plastic area are dependent on the type of coal used and the grain size of the feed components, but the invention is based on the fact that the type of coal and grain size are largely predetermined in normal coking plant operation and rather the dependence on the respective coke quality Coking of the operating conditions and the pretreatment of the input material or the use of coking-active auxiliaries is the main reason. At the same time, the invention is based on the fact that the reactions in the plastic zone largely predetermine the phase of the reconsolidation, but the reverse is not ensured.
  • the quality of the coke is therefore controlled in that the distance of the plastic zone from the furnace wall is measured at predetermined time intervals, compared with a setpoint and the deviation from the setpoint by adding preheated coal and / or carbo and / or petrostatic coal binder is balanced.
  • the width of the plastic zone is the decisive factor influencing the coke quality.
  • Your measurement enables a precise prediction of the coke quality that is set and is therefore to be used as a central control variable for the provision of the components used, the course of the coking process and for the resulting coke quality as a target variable.
  • carbo- and / or petro-derived binders reduces the softening temperature of the furnace stock, but hardly changes its reconsolidation temperature. A larger temperature range is created for the plastic zone. This results in a spatial expansion of the plastic zone, so that the essential effects explained above in the duration of the plasticity, in the course of the reactions, in the gas bubble size and the homogeneity of the gas bubble distribution.
  • preheated coal according to the invention also results in a reduction in the temperature gradient.
  • this causes the plastic area to widen as a function of the distance from the chamber wall, this effect gaining in size and importance with increasing cooking time.
  • the lower heating rate associated with the lower temperature gradient is also of great importance for the post-plastic area (contraction maximum at about 600 ° C).
  • the mechanical stresses are reduced. This reduces the tendency to crack.
  • the output on blast furnace coke increases as a success.
  • the abrasion resistance (MIO) and the piece strength (M 4o ) increase according to ISO.
  • the average pore diameter of the coke is significantly reduced.
  • the average wall thickness of the cell walls of the coke structure increases, which increases the structural strength of the coke.
  • the width of the plastic area is measured using the temperature distribution in the furnace stock. I.e. Temperature measurements are carried out at closely spaced intervals from the chamber wall to the center of the chamber. The resulting temperature values are compared with the temperature setpoints that determine the minimum width of the plastic area. If the temperature falls below the specified target temperature, coal binders and / or preheated coal are added to the feed mixture in subsequent furnace batches until the desired target temperatures (minimum temperatures) are reached in the furnace. Corresponding to the plastic area that changes during the coking process, the target temperatures corresponding to the limit values of the plastic area must be observed at different points in the cross-section of the furnace in each coking phase.
  • the setpoint temperature can remain constant and assume one of the values between 320 and 480 ° C. A value at the lower temperature limit is preferably selected.
  • the spatial distances can be taken into account by a number of temperature measuring devices distributed over the width of the furnace chamber or by a single temperature measuring device that can be moved back and forth across the width of the furnace chamber.
  • Thermocouples can be used as temperature measuring devices, which are preferably provided with protective tubes and inserted into the furnace stock before the coking begins. With a suitable choice of material for the protective tubes, longer service lives can be achieved.
  • thermocouples can be placed in an electrical comparison circuit with setpoint devices, e.g. Potentiometer, bring.
  • setpoint devices e.g. Potentiometer
  • the differential voltage can then be taken as a measure of the necessary addition of preheated coal and / or advantageous coal binder.
  • Exceeding the target values specified according to the invention is harmless, since with the addition of preheated coal and advantageous coal binders, only a limited enlargement of the plastic zone can be achieved.
  • the limit for the admixture of preheated coal results from the maximum preheat temperature of 250 ° C, the limit for the coal binder from the maximum admixable amount, which should not exceed a certain ratio of carbon substance to the amount of plasticizing additives, taking into account the coke quality.
  • the temperature changes in the furnace batch run symmetrically towards the center of the coke oven. It is therefore sufficient to measure the area between a chamber wall and the center of the furnace.
  • protective tubes are installed in the oven at intervals of 20 mm, which protrude from above into the furnace bed when the furnace is full and during the coking process allow the introduction of thermocouples and temperature measurements in the furnace stock up to half of the furnace batch.
  • the temperature is measured at the prepared measuring points every hour.
  • the resulting actual values are compared with the target values belonging to the hourly measurement. It is also possible to choose other time intervals for the temperature measurement. At time intervals that lie between the predetermined half-hourly and hourly measurements, a linear extrapolation is carried out between the predetermined target values of the neighboring half-hourly or hourly temperature measurements.
  • the target temperature is a temperature between 320 and 480 ° C. In other words, depending on the progress of the coking process, after one, two, four, etc. hours, there is a place in the furnace half covered by the temperature measurement, at which the temperature of the charge should be at least 320 ° C. Exceeding this temperature is harmless. On the other hand, if the temperature falls below the target temperature, there is no guarantee that high-quality blast furnace coke will be produced.
  • the target temperature always indicates the target position at the boundary of the plastic zone facing the center of the chamber.
  • the control variable in the exemplary embodiment is the boundary of the plastic zone facing the center of the chamber. In some cases, the other boundary of the plastic zone can also be selected as the control variable.
  • the target temperature is 480 ° C and the minimum distance from the chamber wall is equal to the minimum distance for a target temperature of 320 ° C minus the minimum width specified according to the invention for the plastic zone.
  • the following minimum distances from the chamber wall result after four, six, eight and ten hours of cooking time for the target temperature 320 ° C.
  • the difference between the minimum distances and the desired distances is reduced, for example, by adding Carbopech and / or preheated coal.
  • Carbopech brings a maximum 0.5-0.8 mm reduction in the difference per percent of Carbopech admixture.
  • An upper limit of around 15% Carbopech can be assumed.
  • the coke quality changes back to negative because the amount of plastic components in relation to the remaining carbon structure becomes too large (depending on the type of coal).
  • the following approximations to the specified minimum distances of the 320 ° C limit value could be measured by adding 15% Carbopech at the cooking intervals of four, six, eight and ten hours selected here: 69 mm instead of 60 mm after four hours, instead of 104 mm after six Hours 114mm, instead of 145 mm after eight hours 156 mm and instead of 184 mm after ten hours 190 mm.
  • preheated coal The differences to the minimum distance required to achieve the specified target values after the carbopech was added could be eliminated by adding preheated coal to the moist feed.
  • preheated coal instead of Carbopech, only the addition of preheated coal is used.
  • the addition of preheated coal brings about 4 mm approximation per 10% addition of preheated coal of 220 ° C preheating temperature. This generally applies to all preheating temperatures above 200 ° C.
  • the target values specified according to the invention apply not only to the insert coal selected in the exemplary embodiment but also to other insert coal or insert mixtures, since the influence of the thermal conductivity of the insert material on the course of the temperature fields is small.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Coke Industry (AREA)

Claims (4)

1. Procédé de réglage de la qualité du coke provenant de mélanges de charges de charbon, qui sont cokéfiés dans un four à coke par chauffage indirect et en l'absence d'air, dans lequel les mélanges de charges de charbon subissent pendant le processus de cokéfaction, au passage de la plage de températures de 320 à 550°C, une plastification qui se déplace, au fur et à mesure de l'augmentation de la durée de cuisson, de la paroi du four vers le milieu du four, caractérisé en ce qu'à des intervalles de temps prédéterminés la distance entre la zone plastique et la paroi du four est mesurée et comparée avec une valeur de seuil et en ce que la déviation par rapport à la valeur de seuil est compensée par une addition de charbon préchauffé et/ou de liant carboné d'origine carbonifère et/ou pétrologique.
2. Procédé suivant la revendication 1, caractérisé par au moins deux mesures dans un intervalle de temps d'au moins une heure.
3. Procédé suivant l'une des revendications 1 ou 2, caractérisé en ce que les points de mesure sont répartis, à une certaine distance dans l'espace, sur la largeur de la chambre du four à coke (charge du four).
4. Procédé suivant l'une des revendications 1 à 3, caractérisé en ce que la plage de températures de la plastification, qui sert de base à la mesure de la zone plastique, est comprise entre 350 et 480°C.
EP81105965A 1980-09-26 1981-07-29 Procédé de réglage de la qualité de coke Expired EP0048802B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3040331 1980-09-26
DE19803040331 DE3040331A1 (de) 1980-10-25 1980-10-25 Verfahren zur steuerung der koksqualitaet

Publications (3)

Publication Number Publication Date
EP0048802A2 EP0048802A2 (fr) 1982-04-07
EP0048802A3 EP0048802A3 (en) 1982-10-06
EP0048802B1 true EP0048802B1 (fr) 1985-06-12

Family

ID=6115198

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81105965A Expired EP0048802B1 (fr) 1980-09-26 1981-07-29 Procédé de réglage de la qualité de coke

Country Status (4)

Country Link
US (1) US4421604A (fr)
EP (1) EP0048802B1 (fr)
JP (1) JPS57100182A (fr)
DE (1) DE3040331A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2149421B (en) * 1983-11-07 1986-08-20 Mitsubishi Chem Ind Method of regulating fuel for a coke oven
ES8801355A1 (es) * 1985-05-06 1988-01-01 Didier Eng Un metodo para generar coque con su correspondiente recipiente e instalacion
TWI453382B (zh) * 2012-12-28 2014-09-21 China Steel Corp 焦炭溫度量測系統
RU2637965C1 (ru) * 2016-11-02 2017-12-08 Общество С Ограниченной Ответственностью "Промышленные Инновационные Технологии Национальной Коксохимической Ассоциации" (Ооо "Проминтех Нка") Нефтяная коксующая добавка
CN107038529B (zh) * 2017-04-07 2023-09-12 天地科技股份有限公司 条带充填体稳定性的评价方法
CN110739029B (zh) * 2019-09-20 2022-06-07 武汉钢铁有限公司 煤质评价方法及装置

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE564101A (fr) *
FR752468A (fr) * 1932-03-14 1933-09-23 Mij Voor Keramische En Chemisc Perfectionnements à la fabrication du coke à température moyenne
GB779218A (en) * 1954-09-21 1957-07-17 Charbonnages De France An improved method of producing metallurgical coke
DE1771688B1 (de) * 1968-06-26 1972-02-03 Koppers Gmbh Heinrich Verfahren zur Regelung der Beheizung von Verkokungsoefen
DE2257668B1 (de) * 1972-11-24 1973-09-06 Bergwerksverband Gmbh, 4300 Essen Verfahren zur herstellung von steinkohlenkoks mit erhoehter stueckgroesse und verbesserter stueckfestigkeit im hochleistungs-horizontalkammerofen
US3970523A (en) * 1972-11-24 1976-07-20 Bergwerksverband Gmbh Processes of producing cokes of large lump size and improved strength from bituminous coals
JPS5156801A (ja) * 1974-11-14 1976-05-18 Sumitomo Metal Ind Yakinyokookususeizonikyosuru kaishitsutanno seizohoho
ZA753956B (en) * 1975-06-20 1977-07-27 H Hahn Improvements in carbonaceous material
CA1114765A (fr) * 1978-04-28 1981-12-22 Keith Belinko Production de coke metallurgique a partir de houilles a faible coefficient de cokefaction a l'aide de residus tires du traitement du bitume extrait des sables bitumineux
DE2819232C2 (de) * 1978-05-02 1985-01-17 Carl Still Gmbh & Co Kg, 4350 Recklinghausen Verfahren zum Vorerhitzen und unmittelbar anschließenden Verkoken von Kohle
FR2464984A1 (fr) * 1979-09-10 1981-03-20 Charbonnages De France Procede de traitement par sechage et/ou prechauffage de charbon a cokefier et installation pour la mise en oeuvre du procede

Also Published As

Publication number Publication date
JPS57100182A (en) 1982-06-22
EP0048802A3 (en) 1982-10-06
US4421604A (en) 1983-12-20
EP0048802A2 (fr) 1982-04-07
DE3040331A1 (de) 1982-05-27
DE3040331C2 (fr) 1988-12-15

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