414853 經濟部智慧財產局員工消货合作社印製 B7 五、發明說明（/ ) 本發明係關於一種細粒加料電弧爐方法。尤指將一種 細粒形式的預先還原鐵礦石加入—用以製造鋼或鐵合金之 電弧爐的方法。 在由廢料生產鋼的電弧爐領域中，如何用一種預先還 原鐵礦石來替代加入廢料的部分係爲已知的。爲此’預先 還原鐵礦石是以九狀或球狀加入，其僅被允許從熔爐的頂 部開口中落入熔化的鐵水中。該等九或球經過覆蓋於鋼及 熔化物液體上的殘渣而順利地與已熔化的鋼接觸。 由於現已瞭解以細粒方式生產預先還原鐵礦石的方法 ，因此若能將預先還原的鐵礦石直接以細粒方式加入是吸 引人的。然而，以細粒方式加入帶來重大問題。它必須在 事實上保証細粒湊入金屬浴槽中，即必須防止煙霧帶走細 粒以及防止細粒漂浮在殘渣的表面。因此僅將細粒灑入電 弧爐是不可行的。 因而建議細粒應該懸浮在一注入到熔融浴槽之載送氣 體中。爲避免細粒被煙霧帶走，並且確保細粒滲入金屬熔 液中，必須要有高速噴射的細粒。然而，雖然對相對較小 的質量流率的噴射來說沒有大問題，但對較大的質量流率 而言則不然。對大的質量流率而言，高速噴射的細粒具有 使浴槽溢出並且/或導致電弧不可接收的干擾的危險。這 就說明爲何直至目前細料的真空注入仍被限制在每根噴管 每分鐘的流率在一百公斤左右。然而從冶金觀點看來，需 要藉由這一方法能每分鐘將數噸的預先還原鐵礦石加入到 電弧爐中去。 ____ 3 紙張尺度適用中國Ϊ家標準（CNS)Ar規格（210 X 297¾- — 111·—:---7---(> --------^« · I I I I---- (請先閱讀背面之注意事項再填寫本頁) 414853 A7 ----— ___B7__ 五、發明說明（2 ) 本發明的目的即在於提出一種方法，在更有利的條件 下’使細料以更高的流率加入至電爐中成爲可能。 根據本發明之方法’細料是以懸浮在一載送氣體中的 細料噴射物的方式再加入到一電弧爐中。爲使射入條件更 爲有利，本發明提出在該細料噴射物周圍圍繞一層速度明 顯高於細料噴射物的載送氣體之次氣體。此高速周圍層氣 體在細料噴射物周圍形成一種保護外層。它在噴射管的出 □處集中並保護該細料噴射物，從而防止細料被煙霧帶走 。類似地，其利於噴射物滲入熔融浴槽中並且還降低了噴 管出口堵塞的危險。因而也可以相對較低的細料噴射速度 來工作。然而，因爲藉由噴射物導致的浴槽干擾量-即波 的尺寸，溢出和濺出的範圍到達一個由噴射物推動力-即 由質量流率和噴射速度所產生的亞音速噴射物-決定的第 一近似値，所以如果速度降低，細料中間的噴射物可以較 高的質量流率進行工作。有利地，該細粒的粒徑範圍係在 0〜5公釐之間，更佳地是在0〜3公釐之間。 次氣體的速度最好至少爲載送氣體的十倍。載送氣體 的速度最好被限制在1 2至2 5米/秒之間。在此條件下 ，噴射物的質量流率有可能在1 5至4 0公斤/秒。 次氣體的速度最好接近音速。雖然這需要更爲複雜的 注射噴管，它也可達到音速。 較佳地，載送氣體的速度和細粒的質量流率被確定以 至於注射噴管出口處細粒噴射物的推動力在3 0 0至5 ◦ Ο N之間。 4 ^紙張尺度適用國國家標準（CNS)f規格（210 χ 297公S " (請先閱讀背面之'注音？事項再填寫本頁) 裝---------：訂--------- 經濟部智慧財產局具工消費合作社印製 經濟部智慧財產局具工消費合作杜印製 414853 A7 B7 五、發明說明（》） 應當了解根據本發明的方法尤其適用於將細料狀的于頁 先還原鐵礦石注入至電弧爐中。因爲這些細料大都包含過 量的碳，所以次氣體爲氧較佳，其流速大致與用來氧化細 料噴射物中過量的碳所必需的流速相符。次氣體氧同過量 碳進行的氧化作用在每一處由於氣體的冷卻作用和細料的 熔化而消耗了大量熱量的地方釋放出可觀的熱能。g止匕， 減小了熔融浴槽凝固的危險或靠近噴出物衝擊點處，胃另ij 是當該點靠近爐壁時，形成附著的危險。根據本發明的$ 法因而能使細料導入處與該電弧或該等電弧相距一段距离隹 ，從而也降低了影響電弧穩定性的危險。 在上一段的條件下，次氣體的速度最好是確定以次氣 體的推力處於1 0 0至3 Ο Ο N之間。通常，最好將噴身寸 物的總推力-即細料噴射物的推力和次氣體的總和—限制 在5 0 0至7 Ο Ο N之間。 仍要指出，爲了每分鐘注入數噸的細料，最好將細料 的流率分在幾個噴管中，這樣每根噴管細料的流率可以被 限制在2 5公斤/秒以下。 透過以下給出的一作爲例証並結合參考隨附的圖式的 實施例，本發明的其它特點和特征將會顯現。其顯示了： 第一圖：通過一實施本發明之加入細料方法的電弧爐 的示意的垂直橫剖面； 弟一圖：通過第一圖之電弧爐的水平橫剖面。 圖中，相同的參考數字表示了相同或相似的元件。 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） — — ι~;ι·ι1 — — — > I I — I — .— fjlll — · (請先閱讀背面之注意事項再填窝本頁) 414853 A7 ----— —_B7 五、發明說明（4) 第一圖和第二圖顯示了一帶有三個電極1 2 -、χ 2 "、1 2"’的電弧爐的示意狀況，這些電極目前用於鋼或 鐵合金的生產。參考數字1 4代表了電弧爐1 0中的金屬 浴槽（即’液態之熔融金屬）。該金屬浴槽1 4被〜層泡 沫狀的熔渣16所覆蓋（見第一圖）。 爲大量加入細料狀的預先還原鐵礦石，使用了^個噴 管1 8、2 〇、2 2。該等噴管1 8、2〇、2 2各界定 了一中央導管2 4，其環繞有一環狀導管2 6。懸浮在載 送氣體’一般爲氧氣中的細料從中央導管2 4中流過。在 圖中’懸浮在這些載送氣體中的細料是由帶點區域來表示 的。氧氣是從噴管1 8、2 0、2 2的環狀導管2 6中通 過的。 根據本發明的一個重要特徵，氧氣具有明顯高於中央 導管出口處的載送氣體的速度。換句話說，一層次氣體， 此狀況中的氧氣，以明顯高於載送氣體的速度包瞻I了該細 料噴射物。正如以上所述，該高速外層氣體在細料的中央 噴射物周圍形成了 一種保護外層。它使得細料噴射物集中 在注入噴管18、20、22的出口處，並且防止細料被 煙霧帶走。它也有利於噴射物滲入熔融浴槽1 4中並且降 低噴管出口堵塞的危險。因而可在中央導管2 4的出口處 以較低速度的載送氣體進行工作。 工作實例： 6 表紙張又度適用中國國家標準（CNS>M規格（210 >^297公釐) ^ (請先閱讀背面之注意ί項再填寫本頁) 裝 訂 經濟部智慧財產局員工消費合作社印製 414853 A7 Β7 五、發明說明（Γ ) 要求係注入個電弧爐中，其具有每一鑄件1〇 〇噸， 4噸/分的DR I (直接還原鐵）細料之產能，在一·多層 熔爐或在一流動床中產生的85%金屬和含有43%碳 的類型。該流量被分在上述三個噴管1 8、20、2 2中 ，即各噴管應當以約22·2公斤/秒的流量注入。 噴管出口處細料噴射物的速度限制在約2 0米/秒以 便使噴管出口處的中央噴射物的推力爲22.2公斤/秒 x2 0 米/秒= 4441NI。 環狀導管中氧氣的流率以便與用來將細料噴射物中的 過量碳氧化成一氧化碳所必需的氧的流速大致相符的方式 而確定的。這使氧的流速接近約1 2 0 0立方米/小時。 環狀導管2 6出口處氧氣的速度接近於音速（即，速 度約爲中央導管2 4中載送氣體的1 5倍），其產生的對 氧氣噴射物的推力約爲1 5 0 N。 因此，由音速氧氣所包圍的D R I噴射物的總推力因 此爲6 0 0 N，其足夠低而使浴槽中產生的干擾處於一可 接受的水準。 經濟部智慧財產局員工消費合作社印製 £ j---1---'ί 裝·-- (請先閱讀背面之注意事項再填寫本頁) 另外，在第二圖中可以看到噴射物的衝擊點離開電極 有一些距離，以避免對電弧產生太大的干擾。因爲過量碳 的化合物釋放了大量的熱，其可足以避免金屬液凝固和注 入點處附著的形成。 仍要指出’本發明0勺方法可以讎的噴冑（如第一及 第二圖中所示）和以垂直的噴管進行實施。 本紙張尺度適用中國國家標準（CNS>A4規格（21^7^7^ 414853 五、發明說明（t) 元件符號說明 1〇 電弧爐 1 2 ’ ' 1 2 ”、1 2 ’” 電極 14 金屬浴槽 16 沬泡狀熔渣層 1 8、2 0、2 2 噴管 24 中央導管 26 環狀導管 — 1 Tf- ., i> --------訂·-------- (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 本紙張又度適用中國國家標準（CNS)A-l規格（210 X 297公釐）414853 Printed by the Consumer Goods Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs B7 V. Description of the Invention (/) The present invention relates to a fine-grained electric arc furnace method. In particular, a method of adding a pre-reduced iron ore in the form of fine particles to an electric arc furnace for manufacturing steel or iron alloys. In the field of electric arc furnaces for the production of steel from scrap, it is known how to replace the part added with scrap with a pre-reduced iron ore. For this purpose, the 'pre-reduced iron ore is added in a nine or spherical shape, which is only allowed to fall into the molten molten iron from the top opening of the furnace. The nine or balls pass through the residue covering the steel and the melt liquid, and smoothly contact the molten steel. Since a method for producing pre-reduced iron ore in a fine-grained manner is now known, it would be attractive if the pre-reduced iron ore can be directly added in a fine-grained manner. However, adding in a fine-grained manner poses significant problems. It must in fact ensure that the fine particles fit into the metal bath, that is, it must prevent the smoke from taking away the fine particles and prevent the fine particles from floating on the surface of the residue. It is therefore not feasible to sprinkle only fines into the arc furnace. It is therefore suggested that the fines should be suspended in a carrier gas injected into the molten bath. In order to avoid the fine particles being carried away by the smoke and to ensure that the fine particles penetrate into the molten metal, high-speed spraying of the fine particles is necessary. However, while there is no major problem for relatively small mass flow rate injections, this is not the case for larger mass flow rates. For large mass flow rates, high-speed sprayed fines run the risk of overflowing the bath and / or causing unacceptable interference with the arc. This explains why up to now the vacuum injection of fines has been limited to a flow rate of about one hundred kilograms per minute per nozzle. From a metallurgical point of view, however, it is necessary to be able to add tons of pre-reduced iron ore to the electric arc furnace every minute by this method. ____ 3 The paper size is applicable to the Chinese standard (CNS) Ar specification (210 X 297¾- — 111 · —: --- 7 --- (> -------- ^ «· III I --- -(Please read the notes on the back before filling out this page) 414853 A7 -------- ___B7__ V. Description of the invention (2) The purpose of the present invention is to propose a method to 'make fine materials under more favorable conditions' It is possible to add to the electric furnace at a higher flow rate. According to the method of the present invention, the 'fines' are added to an electric arc furnace in the form of fine material ejections suspended in a carrier gas. To make the injection conditions more To facilitate, the present invention proposes to surround a layer of secondary gas with a velocity that is significantly higher than the carrier gas of the material spray. The high-speed surrounding gas forms a protective outer layer around the material spray. The outlet of the tube concentrates and protects the fine spray material, thereby preventing the fine material from being carried away by the smoke. Similarly, it facilitates the spray material to penetrate into the molten bath and also reduces the risk of clogging the nozzle outlet. Therefore, it can also be relatively compared Low fines spray speed to work. However, because by The amount of bath disturbance caused by the spray-the size of the wave, the range of spillage and splashing-reaches a first approximation determined by the thrust of the spray-the subsonic spray produced by the mass flow rate and spray velocity- Therefore, if the speed is reduced, the ejected material in the middle of the fine material can work at a higher mass flow rate. Advantageously, the particle size range of the fine particles is between 0 and 5 mm, and more preferably between 0 and 3 mm. The speed of the secondary gas is preferably at least ten times that of the carrier gas. The speed of the carrier gas is preferably limited to 12 to 25 meters per second. Under this condition, the mass flow of the ejected material The rate may be 15 to 40 kg / sec. The speed of the sub-gas is preferably close to the speed of sound. Although this requires a more complicated injection nozzle, it can also reach the speed of sound. Preferably, the speed and fineness of the carrier gas The mass flow rate of the granules is determined so that the driving force of the fine particle ejection at the outlet of the injection nozzle is between 300 and 5 ◦ N. 4 ^ The paper size applies the national standard (CNS) f specification (210 χ 297 Public S " (Please read the 'Zhuyin on the back? Matters before filling out this page) ----: Order --------- Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs and the Industrial Cooperative Cooperative, printed by the Ministry of Economic Affairs and the Industrial and Consumer Cooperatives of the Ministry of Economic Affairs, printed by 414853 A7 B7 V. Description of the Invention (") The method according to the present invention is particularly suitable for injecting fine-particulate pre-reduced iron ore into an electric arc furnace. Because these fines mostly contain excessive carbon, the secondary gas is preferably oxygen, and its flow rate is roughly the same as that used for The necessary flow rate for oxidizing the excess carbon in the fines ejection is consistent. The oxidation of the sub-gas oxygen with the excess carbon releases a considerable amount of heat every place where a large amount of heat is consumed due to the cooling of the gas and the melting of the fines. Thermal energy. g stop the dagger, reduce the danger of solidification of the molten bath or near the impact point of the spray, and the stomach ij is the danger of adhesion when the point is close to the furnace wall. The $ method according to the present invention can thus distance the lead-in point of the fines from the arc or arcs by a distance 隹, thereby reducing the danger of affecting the stability of the arc. Under the conditions of the previous paragraph, the speed of the secondary gas is preferably determined to be between 100 and 3 00 N. In general, it is best to limit the total thrust of the spray object—that is, the sum of the thrust of the fine spray and the secondary gas—to 500 to 7 〇 N. It should still be pointed out that in order to inject tons of fines per minute, it is best to divide the flow rate of the fines into several nozzles, so that the flow rate of the fines per nozzle can be limited to less than 25 kg / s . Other features and characteristics of the present invention will become apparent through an embodiment given below as an example and with reference to the accompanying drawings. It shows: the first figure: a schematic vertical cross-section of an electric arc furnace through a method for adding fines according to the present invention; the second figure: the horizontal cross-section of an electric arc furnace through the first figure. In the figures, the same reference numerals indicate the same or similar elements. 5 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) — — ι ~; ι · ι1 — — — > II — I —. — Fjlll — · (Please read the notes on the back first Refill this page) 414853 A7 ----——-_ B7 V. Description of the invention (4) The first and second pictures show an arc with three electrodes 1 2-, χ 2 ", 1 2 " ' The schematic state of the furnace, these electrodes are currently used in the production of steel or ferroalloys. Reference numeral 14 denotes a metal bath in the electric arc furnace 10 (i.e., a 'liquid molten metal'). The metal bath 14 is covered with a foam layer of slag 16 (see the first figure). In order to add a large amount of finely reduced pre-reduced iron ore, ^ nozzles 18, 20, 22 were used. The nozzles 18, 20, 22 each define a central duct 24, which surrounds an annular duct 26. Fines suspended in a carrier gas, typically oxygen, flow through the central conduit 24. In the figure, the fines suspended in these carrier gases are represented by dotted areas. Oxygen is passed through the annular ducts 26 of the nozzles 18, 20, 22. According to an important feature of the invention, the oxygen has a significantly higher velocity than the carrier gas at the outlet of the central duct. In other words, a layer of gas, the oxygen in this condition, contains the fine jet at a significantly higher speed than the carrier gas. As mentioned above, the high-speed outer layer gas forms a protective outer layer around the center jet of the fines. It allows the fines to be concentrated at the outlets of the injection nozzles 18, 20, 22 and prevents the fines from being carried away by the smoke. It also facilitates the penetration of the spray into the molten bath 14 and reduces the risk of clogging of the nozzle outlet. It is thus possible to work at a lower velocity carrier gas at the outlet of the central duct 24. Working example: 6 sheets of paper are again applicable to Chinese national standards (CNS > M specification (210 > ^ 297mm) ^ (Please read the note on the back before filling this page) Binding of the Intellectual Property Bureau Staff Consumer Cooperatives Printed 414853 A7 B7 V. Description of the invention (Γ) The requirement is to be injected into an electric arc furnace, which has a capacity of 100 tons per casting and 4 tons / min of DR I (direct reduced iron) fines. Multi-layer furnaces or 85% metal and 43% carbon types produced in a fluidized bed. The flow is divided into the above three nozzles 18, 20, 22, that is, each nozzle should be about 22 · 2 The flow rate of kg / s is injected. The speed of the fine spray at the nozzle outlet is limited to about 20 m / s so that the thrust of the central spray at the nozzle outlet is 22.2 kg / s x 20 m / s = 4441NI. The flow rate of oxygen in the annular conduit is determined in a manner that approximately matches the flow rate of oxygen necessary to oxidize the excess carbon in the fines ejection to carbon monoxide. This brings the flow rate of oxygen close to about 1 200 cubic meters. M / h. The velocity of the oxygen at the exit of the annular duct 2 6 is close to the speed of sound. That is, the velocity is about 15 times that of the carrier gas in the central duct 24), and the thrust to the oxygen jet is about 150 N. Therefore, the total thrust of the DRI jet surrounded by sonic oxygen is therefore It is 60 0 N, which is low enough so that the interference generated in the bath is at an acceptable level. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. (Read the precautions on the back before filling in this page.) In addition, in the second picture, you can see that the impact point of the spray is some distance away from the electrode to avoid too much interference with the arc. Because excessive carbon compounds release a large amount Heat, which can be sufficient to avoid the solidification of the metal liquid and the formation of adhesion at the injection point. It should still be pointed out that the 0 spoon method of the present invention can be sprayed (as shown in the first and second figures) and a vertical nozzle Implementation. This paper size applies the Chinese national standard (CNS > A4 specification (21 ^ 7 ^ 7 ^ 414853) V. Description of the invention (t) Element symbol description 10 Arc furnace 1 2 '' 1 2 ', 1 2' 'electrode 14 metal bath 16 blistering slag layer 1 8, 2 0 2 2 Nozzle 24 Central Duct 26 Ring Duct — 1 Tf-., I > -------- Order · -------- (Please read the precautions on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, this paper is also compatible with the Chinese National Standard (CNS) Al specification (210 X 297 mm)