TW200530405A

TW200530405A - Process for recovery of zinc and iron from EAF dust by reduction

Info

Publication number: TW200530405A
Application number: TW93105475A
Authority: TW
Inventors: Chia-Cheng Wu; Eberhard Gock
Original assignee: Chia-Cheng Wu
Priority date: 2004-03-03
Filing date: 2004-03-03
Publication date: 2005-09-16
Also published as: TWI241348B

Abstract

A new method is invented to recovery the metals zinc and iron from the EAF (Electric Are Furnace) dust. The main process is reduction with carbon monoxide gas as reduction agent after a pre-treatment. The EAF dust is first pelletized by adding water. The raw pellets are fed into the pre-treatment stage under oxidizing condition to vaporize the chlorides and lead compounds. The pellets free of chlorides and lead undergo then the reduction in carbon monoxide gas flow. After the full reduction, zinc oxide and iron oxide are fully reduced to their metallic form. Zinc, due to its low boiling point, is vaporized and carried out by the reaction gas flow. The obtaining of metallic zinc can be achieved in a condenser. The residue is iron sponge. After cooling, it can be re-used as raw material in iron metallurgy. This new process solves not only the long term problem of high chlorides/lead contents in EAF dust, but also provides the nearly full recycling of EAF dust by mean of winning the reusable zinc and iron in their metallic form.

Description

五、發明說明（1) 【發明所屬之技術領域本發明係有關於—^。有價金屬之方《，特別係：：電：壚煉鋼業集塵灰内所含原處理，並以一氧化碳氣體你I則處理後之集塵灰進行還及鐵兩資源物。、為還原劑，後取得金屬態辞【先前技術】 2001年台灣之鋼產量八久以來便是屬於鐵眘、、盾η ”、、王世界第十位，電弧爐技術長電弧爐高溫融熔還原德γ =冉生重要的一環，報廢鋼鐵在鋼材或合金。⑪年來由：f爐調理，而被製成不同品質之 f + ^ , Λ ^ ^ 由於鋼鐵製品鍍辞防鏽比例曰增，相對地，由廢鐵帶入電弧爐溫冶煉條件下，鋅盡數：：鋅里也比以在增加1，在面 ^ ^ ^ ^ $试數揮發至氣氛環境中，並由喷入爐内之撥掉氣體帶出，衣妳^ ^ ^ . 在&降溫集塵過程後被以收集在集塵灰，内。經由攪拌氣體帶出的尚有融鐵液滴及少部份鐵蒸氣，會與辞在氧化條件下形成混合氧化物。一些易揮發之化合物如_化物鹽類及鉛化合物，同為集塵灰中主要成份。除此之外，一些微量之金屬如錳、鎂、銅等，亦可分別以氧化物形式存在於集塵灰中。一般電弧爐集塵灰之主要元素成份如下表一：V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to-^. The formula of valuable metals "Special :: Electricity: The raw materials contained in the dust collected by the steelmaking industry, and the treated dust collected with carbon monoxide gas is returned to iron and iron resources. , As a reducing agent, and later obtained the metal state [previous technology] Taiwan ’s steel production in 2001 has belonged to Tie Shen, Shield η, and Wang Shishi for the eighth long time. The reduction of γ = an important part of Ran Sheng, scrap steel is in steel or alloy. In the past year, it has been adjusted by f furnace and made into different quality f + ^, Λ ^ ^ As the rust prevention ratio of steel products has increased, In contrast, when the scrap iron is brought into the electric arc furnace under the conditions of warm smelting, the number of zinc :: zinc is also increased by 1 in the surface ^ ^ ^ ^ $ The test number is volatilized to the atmosphere and sprayed into the furnace. Remove the gas and bring it out, and you ^ ^ ^. After the & cooling and dust collecting process, it is collected in the dust collecting ash. The molten iron droplets and a small part of the iron vapor brought out by the stirring gas will be Mixed oxides are formed under oxidizing conditions. Some volatile compounds such as compound salts and lead compounds are also the main components in dust collection ash. In addition, some trace metals such as manganese, magnesium, copper, etc. , Can also exist in the form of oxides in the dust ash. The main elements of the furnace dust ash are as follows:

200530405 五、發明說明（2) 元素重量百分比[%] 辞 20-30 鐵 25-40 錯 2-4.0 納 0.3-23 鉀 0.1-20 氯 0.5-25 氟 0.1-0.3 鎂 0.5-1.5 猛 25-46 銅 0.2-0.8 而電弧爐含鋅集塵灰中各主要化合物之融、沸點則如下表二：第8頁 200530405200530405 V. Description of the invention (2) Element weight percentage [%] 20-30 iron 25-40 wrong 2-4.0 sodium 0.3-23 potassium 0.1-20 chlorine 0.5-25 fluorine 0.1-0.3 magnesium 0.5-1.5 strong 25-46 Copper 0.2-0.8, while the melting and boiling points of the main compounds in the zinc-containing dust collection ash of the electric arc furnace are shown in Table II below: Page 8 200530405

五、發明說明（3) 化錄 r， r 〆、、' 1：ΙίΙΙΙίΙΙΙΙΙΙ1Ι||ΐΡΙΙΙ1ββ 辦缺晶石 ZnFe2〇4V. Description of the invention (3) Catalogue r, r 〆 ,, '': ΙίΙΙΙίΙΙΙΙΙΙΙ1Ι || ΐΡΙΙΙ1ββ Doped crystal ZnFe2〇4

氧化辞ZnO fcfb^Pba2Oxidation ZnO fcfb ^ Pba2

liSibO 電弧爐集塵灰之晶體成份組成與鋅鐵比值有密 ΐ石鐵比值低於約〇· 58時，兩金屬是以難溶之辞鐵尖曰日石或其混合相位存在（ZnxFe3— χ〇4，〇〈 2，量的升高，多餘的鋅便以可溶之氧化鋅形 k气台灣目前電弧爐煉鋼業操作條件 ^ ^ 。就 ⑽之辞；在歐美先進國家如德目，°由/電塵弧灰:^ 的改進及銦口供处办… 田於電弧爐#作條件 30%或更古，鱼又/ 、激增，電弧爐集塵灰内含鋅量達量之資VV再者Λ㈣（如閃辞礦）相較，實為-高含潰方法取出回收之U化辞具有两度之可溶性，可用浸溶性則相當低，若铲對i:鋅鐵尖晶石及其混合晶體之可右欲對鋅達到高回收率，問題核心就在於liSibO The composition of the crystalline components of the dust collection ash of the electric arc furnace and the ratio of zinc to iron. The density of the compacted iron is lower than about 0.58. 〇4, 〇 <2, the amount of excess zinc will be dissolved in the form of soluble zinc oxide gas Taiwan's current operating conditions of electric arc furnace steelmaking industry ^ ^. In the words; in advanced countries in Europe and the United States, such as Germany, ° You / Electric Dust Arc Ash: Improvement of ^ and indium supply ... Tian Yu Arc Furnace # Operating conditions 30% or more, fish and / or surge, the amount of zinc in the arc furnace dust ash is up to VV In addition, compared with Λ㈣ (such as flash ore), the U chemistry taken out and recovered by the high content method has two degrees of solubility, and the usable solubility is quite low. The core of the mixed crystal is to achieve a high recovery rate of zinc, the core of the problem lies in

第9頁 200530405 五、發明說明（4) 如何有效分解破壞難溶之鋅鐵尖晶石。、至目前為止，用於回收電弧爐集塵灰之技術主要可八為溼式化學及高溫冶煉技術兩大類·· 刀 A、·在濕式化學技術方面，應用鋅之酸性或鹼性溶出，以及用強酸鹼破壞鋅鐵尖晶石，雖可經電解後取言純度鋅，但後續之廢水及廢酸、鹼問題、耗費大量化品及回收率偏低等，一直為此類技術推廣之障礙，·再:、若欲將殘渣回爐，必須將殘渣内之含辞量降至一定程度以 I^ Γ f =形成辞塊而對爐體產生阻塞之負面影響，而濕式化學技術產生之浸清碚、、杏 .=玍之/文/貝殘渣，由於難溶之辞鐵尖晶石内尚含辞，故殘餘辞量通常高於此限許多。此外，另有方法利用弱酸性條H對自由氧化料份作时 =之2潰殘逢混入水泥製品中，用於建材等用途， =法之鋅回收率約在85%至90%，鐵則全數形成浸潰殘逢後，予以拋棄或用於建材等。一 B高^技術中最廣為應用#，當，旋轉窯技術闲^^ Z#二了）’該法為依據傳統高溫冶煉技術，應 ::325超過12°0。°溫度下對辞進行回收，主要反 ::二-二：爐。其最大缺點為：回收之粗氧化鋅中含 = :類，不但影響後續之集塵設施，純度及價為，二於…人播所產出之粗氧化鋅無法為煉辞業者大量接亡J:付：\辞業者需求’則需提高成本針對鹽類進行二m避免鐵高溫熔融造成爐熏出料口結渣轉熏技術中必須加入大量石英砂以作為爐逢形 200530405 五、發明說明（5) —*- 成劑，如此施行之缺失··一者降低流程之產能，再者所鈇成之含鐵爐渣僅可被使用於建造路基及級配等低階用途了貫為南經濟資源物質之浪費。 ' 基於上述原因，有鑑於現行回收技術之各項缺失，為有效將有價物質完全資源化並達無二次污染虞慮之目標: 是以本發明人特研發出本發明。且依本發明流程中，可將電5瓜爐集塵灰中含量最高之鋅與鐵兩金屬，經前處理及還原處理後分別以高價值、高純度之金屬狀態取得，同時將處理溫度降至1 00 0 t以下，不僅可節省能源，並有效提高產值及節省投資成本。【發明内容】由於以單一還原步驟為基底之傳統高溫處理方式中， =採用之還原劑多為固體焦炭，同時也是供給反應所需熱月匕之能ΐ來源’故在處理過程中須導入大量助燃空氣；在高於1 20 0 t的反應溫度下，沸點低之成份如鹵化物鹽類及 f化物會首先揮發至氣相環境中；在還原氣氛中氧化鋅及氧化鐵會分別被還原金屬態，低沸點之金屬鋅在蒸發至空氣流中後，再度被空氣令含氧及燃燒產生之二氧化碳氧化，最後與鹽類及鉛化合物一併經冷卻後由除塵設備混合收集之。為解決傳統方式產品純度低及含鐵爐渣最終處置之後續問題，本發明人以一氧化碳氣體為還原劑之處理方法，加以鍛燒前處理步驟，所構成之本發明，不僅可有效Page 9 200530405 V. Description of the invention (4) How to effectively decompose and destroy the insoluble zinc iron spinel. So far, the technologies used to recover the dust collected from electric arc furnaces can be mainly divided into two categories: wet chemistry and high temperature smelting technology. Blade A. In the wet chemistry technology, the acidic or alkaline dissolution of zinc is applied. And the use of strong acids and bases to destroy zinc iron spinel, although the purity of zinc can be used after electrolysis, but subsequent wastewater and waste acids, alkali problems, consumption of large amounts of chemicals, and low recovery rates have been promoted for such technologies. Obstacles, · Re :, If you want to return the residue to the furnace, you must reduce the content of the residue in the residue to a certain extent. I ^ Γ f = formation of a block and the negative impact on the furnace body, and the wet chemical technology produces The dip-clear 碚 ,, apricot. = 玍之 / 文 / 贝残 residue, because there is a word in the insoluble iron spinel, so the amount of residual words is usually much higher than this limit. In addition, there are other methods to use the weakly acidic strip H to make free oxidation materials: = 2 crushed and mixed into cement products for building materials and other purposes; = zinc recovery rate is about 85% to 90%, iron is After the formation of all impregnations, they are discarded or used for building materials. One of the most widely used B high technology is #, when the rotary kiln technology is free ^ ^ Z # 2) ’This method is based on traditional high temperature smelting technology, and should be more than 12 ° 0: 325. The temperature is recovered at °° C, which mainly reflects :: 二-二: furnace. The biggest disadvantage is that the recovered crude zinc oxide contains = :, which not only affects the subsequent dust collection facilities, the purity and price are two, but the crude zinc oxide produced by Renbo cannot be killed by a large number of refiners. J : Pay: \ requirement of resigners' need to increase the cost of salt for two meters to avoid high temperature melting of iron caused by furnace fumigation outlet slagging and fumigation technology must add a large amount of quartz sand as a furnace 200530405 V. Description of the invention ( 5) — *-Additives, such as the lack of implementation. One of them reduces the production capacity of the process, and the resulting iron-containing slag can only be used for low-level uses such as subgrade construction and grading. Material waste. '' Based on the above reasons, in view of various shortcomings of the current recycling technology, in order to effectively complete the valuable resources and achieve the goal of no secondary pollution: the present inventors have specially developed the present invention. According to the process of the present invention, zinc and iron, the two metals with the highest content in the dust collection ash of the electric furnace, can be obtained in a high-value, high-purity metal state after pre-treatment and reduction treatment, respectively, while reducing the processing temperature. Below 1000 t, not only can save energy, but also effectively increase output value and save investment costs. [Summary] In the traditional high-temperature treatment method based on a single reduction step, = the reducing agent used is mostly solid coke, and it is also the energy source for supplying the heat required for the reaction. Therefore, a large amount of combustion support must be introduced during the treatment. Air; at reaction temperatures above 1,200 t, components with low boiling points such as halide salts and f compounds will first volatilize into the gas phase environment; zinc oxide and iron oxide will be reduced to metal states in a reducing atmosphere, respectively. After the low-boiling metal zinc is evaporated into the air stream, it is oxidized again by air to make oxygen and carbon dioxide produced by combustion, and finally it is collected by dust removal equipment after being cooled together with salts and lead compounds. In order to solve the problems of low purity of traditional products and the subsequent disposal of iron-containing slag, the inventors have treated the method with carbon monoxide gas as the reducing agent and added the pre-calcination treatment step. The invention is not only effective

200530405 五、發明說明（6) 純度及低污染等成果，亦可有效避免濕式冶煉技術之不足。以一氧化碳為還原劑進行鋅鐵尖晶石還原反應，會因溫度的不同而達成不同之平衡晶體相位’所以，溫产不僅影響還原反應本身化學熱力學之平衡，亦會影響到二氧化碳與二氧化碳間的Boudouard反應平衡’以及還原氣體中一氧化碳與二氧化之比例，以下詳述之： (一）鋅鐵尖晶石之還原反應一般而言，鋅鐵尖晶石之還原反應可依還原條件，即一氧化碳之供應量，達成如下列第（1)〜（4)式不同亦學平衡狀態： ° '化200530405 V. Description of the invention (6) The results of purity and low pollution can also effectively avoid the disadvantages of wet smelting technology. The reduction reaction of zinc iron spinel with carbon monoxide as a reducing agent will achieve different equilibrium crystal phases due to different temperatures. Therefore, warm production not only affects the chemical thermodynamic equilibrium of the reduction reaction itself, but also affects the relationship between carbon dioxide and carbon dioxide. Boudouard reaction equilibrium 'and the ratio of carbon monoxide to dioxide in the reducing gas are detailed below: (1) Reduction reaction of zinc iron spinel Generally speaking, the reduction reaction of zinc iron spinel can be based on the reduction conditions, that is, carbon monoxide The amount of supply can reach the equilibrium state as different from the following formulas (1) to (4): ° '化

ZnFe204 + 0.33CO o ZnO + 0.67Fe3〇4 + 〇.33C02 (i) ZnFe2〇4 + CO <r> ZnO + 2FeO + C02 (2) ZnFe2〇4 + 3C0 <-> ZnO + 2Fe + 3C02 (3) ZnFe2〇4 + 4CO Zn + 2Fe + 4C〇2 (4) 因反應產物之間會因溫度的作用而形成混合晶體，# 即所謂的固體溶液，故實際狀況下之平衡相位通常無法& 上述之純晶體相位存在；是以在上述反應後可繼續進行下列固體溶液形成反應（第（5 )、（ 6 )式）：ZnFe204 + 0.33CO o ZnO + 0.67Fe3〇4 + 0.33C02 (i) ZnFe2〇4 + CO < r > ZnO + 2FeO + C02 (2) ZnFe2〇4 + 3C0 <-> ZnO + 2Fe + 3C02 (3) ZnFe2〇4 + 4CO Zn + 2Fe + 4C〇2 (4) Because the reaction products will form mixed crystals due to the effect of temperature, # so-called solid solution, so the equilibrium phase under actual conditions is usually not & The above-mentioned pure crystal phase exists; the following solid solution formation reaction can be continued after the above reaction (formulas (5), (6)):

第12頁 200530405 五、發明說明Page 12 200530405 V. Description of the invention

(5)(5)

xZnO+ 3 -三 Fe3〇4+ 1_χ〇2 〇 ZnxFe3 x04 3 ~6xZnO + 3 -Three Fe3〇4 + 1_χ〇2 〇 ZnxFe3 x04 3 ~ 6

尤ZnO + nWFe〇〇 ZnxFekO 其中’第（5)式所需之氧可由二氧化碳供應，所低鋅尖晶石之混合晶體常數X介於〇與1之間。第（6 乂成成之鋅-亞鐵氧化物則具有所謂的混合間隙，混合晶^所^形數X僅落在兩個不同區間〇<χ<〇·2及〇.85〈χ<：1 ，形苇，晶體依鋅鐵比例不同，分別為含鋅之氧化亞鐵與含=混氧化鋅，其中反應物之氧化亞鐵亦可由金屬鐵取代，之 ^混合晶體則為含鐵之氧化辞。由&，在部份停^ 下（即第⑴式至第（3)式），辞與鐵依舊是以結合相=件在，遂藉由全還原至金屬態（即第（4)式）以離之最終目的。』疋王分以上所述之相位狀態，請參閱附件一之「鋅-鐵〜_二兀系統相位圖」可清楚表明，其中以氧原點為中心由1 : 下之放射狀箭號為還原反應進行之方向，隨著一氧化β 應量增加（即降低系統内氣氛環境中氧分壓），相位二二區依序降至第三/四區（Area Ιπ/ιν，如第（1)式） =/六區（AreaV/VI，如第（2)、（3)式），第（4)式所^全選原後之相位穩定區則落在Zn — Fe軸上。 (二）Boudouard 反應：In particular, ZnO + nWFe〇〇 ZnxFekO wherein the oxygen required by the formula (5) can be supplied by carbon dioxide, and the mixed crystal constant X of the low zinc spinel is between 0 and 1. The (6) formed zinc-ferrous oxide has a so-called mixed gap, and the number X of the mixed crystals falls only in two different intervals. 0 < χ < 0.2 and 0.85 <χ < ： 1, shaped reed, the crystals are different in terms of zinc-iron ratio, respectively, zinc-containing ferrous oxide and containing = mixed zinc oxide, wherein the ferrous oxide of the reactant can also be replaced by metallic iron, and ^ mixed crystals are iron-containing Oxidation word. From &, under a partial stop ^ (that is, formula ⑴ to (3)), the combination of rhetoric iron and iron is still in the combined phase = pieces, and then fully reduced to the metal state (ie the ( (4) Formula) To the final purpose of Li. 『Wang Wangfen 'For the phase states mentioned above, please refer to the“ Zinc-Iron ~ _ Erwu System Phase Diagram ”in Annex I. It can be clearly shown that the origin of oxygen is the center. 1: The radial arrow below is the direction in which the reduction reaction proceeds. As the β stress increases (ie, the oxygen partial pressure in the atmosphere in the system is reduced), the phase two and two zones are sequentially reduced to the third and fourth zones ( Area Ιπ / ιν, as in formula (1)) = / Six area (AreaV / VI, as in formulas (2) and (3)), formula (4) ^ Full selection of the original phase A given area is falling Zn - Fe axis (b) the Boudouard reaction:

200530405 五、發明說明（8) "200530405 V. Description of Invention (8) "

Boudouard反應為高溫下一氧化碳及二氧化碳間之轉換，反應式如下： 2C0 (g) C〇2(g) + c (s) + 1 7 2.5 8 kJ/mole (7)Boudouard reaction is the conversion between carbon oxide and carbon dioxide at high temperature. The reaction formula is as follows: 2C0 (g) C〇2 (g) + c (s) + 1 7 2.5 8 kJ / mole (7)

該反應由於牽涉到氣體體積變化及吸/放熱反應，受溫度之影響相當大；在高於1〇〇(pc溫度下，反應平衡落在一氧化碳，含量約佔混合氣體之9 9 %體積百分比，還原能力高；當溫度降至40 0 t，混合氣體則含超過99%之二氧化碳，還原反應則主要由固態碳負責。此反應式已標明熱力學上之平衡狀態，再依動力學判斷，於反應區内還原氣體流中一氧化碳辰度’會與進氣口至反應區之距離、氣體加熱速率及氣體流速有密切關係。由上述兩點可知’溫度變化不僅影響到鋅鐵氧化物還原平衡相位，也主導著還原劑「一氧化碳」的濃度，故為本發明中最重要之操作參數。This reaction involves considerable changes in gas volume and endothermic / exothermic reactions, and is greatly affected by temperature. At temperatures above 100 ° C, the reaction balance falls on carbon monoxide, with a content of approximately 99% by volume of the mixed gas. High reduction ability; when the temperature drops to 40 0 t, the mixed gas contains more than 99% carbon dioxide, and the reduction reaction is mainly responsible for the solid carbon. This reaction formula has indicated the equilibrium state in thermodynamics, and then judged by the kinetics, the reaction The degree of carbon monoxide in the reducing gas flow in the zone is closely related to the distance from the air inlet to the reaction zone, the gas heating rate, and the gas flow rate. From the above two points, we can know that the temperature change not only affects the phase of zinc iron oxide reduction equilibrium, It also dominates the concentration of the reducing agent "carbon monoxide" and is therefore the most important operating parameter in the present invention.

本發明人經由在不同溫度下，以人工合成之高純度鋅鐵失晶石及一氧化碳氣流為還原劑進行還原實驗，導出如第一圖所示之還原反應相位圖；其所使用之反應腔室為一開放系統，持續與外界有物質及能量之交換，所進行之反應處於不平衡狀態；以下茲依不同之溫度範圍加以詳述： (1)低於5 5 0 °C ··在低溫範圍内，鋅鐵尖晶石經部份還原及混合晶體形成反應，可被分解為含鐵之氧化辞、含鋅之氧化亞鐵及低鋅尖晶石等三混合晶體；由於氣體停留時The inventors conducted reduction experiments at different temperatures using artificially synthesized high-purity zinc-iron crystals and carbon monoxide gas streams as reducing agents to derive the phase diagram of the reduction reaction shown in the first figure; the reaction chamber used by it As an open system, there is continuous exchange of material and energy with the outside world, and the reaction is in an unbalanced state; the following are detailed according to different temperature ranges: (1) Below 5 50 ° C ·· In the low temperature range Inside, zinc iron spinel undergoes partial reduction and mixed crystal formation reaction, and can be decomposed into three mixed crystals such as iron-containing oxide, zinc-containing ferrous oxide, and low-zinc spinel; due to gas retention

200530405 五、發明說明（9) 間遠短於Boudouard反應達平衡之需時，故所含之一氧化碳量尚足以將鐵還原為金屬；此外，由於B〇ud〇uard反應之平衡在此溫度下偏向固態碳及二氧化碳，產物中含有大量碳化鐵。 (2 ) 5 5 0 C至6 5 0 C ··在此一範圍内，鋅鐵尖晶石中之二價鐵雖可全數被還原為二價，生成之氧化亞鐵與氧化辞部分繼續結合為如第（6)式所示之混合晶體。碳化鐵之生成機制與上同。 ^ (3)j5〇C至90〇C ··隨著溫度上昇，除了氣體之還原200530405 V. Description of the invention (9) Time is much shorter than the time required for the Boudouard reaction to reach equilibrium, so the amount of carbon monoxide contained is sufficient to reduce iron to metal; in addition, because the equilibrium of the Boudouard reaction is biased at this temperature Solid carbon and carbon dioxide, the product contains a large amount of iron carbide. (2) 5 5 0 C to 6 5 0 C ·· In this range, although the divalent iron in zinc iron spinel can be reduced to divalent in all, the resulting ferrous oxide and oxidized part continue to be combined. It is a mixed crystal represented by the formula (6). The generation mechanism of iron carbide is the same as above. ^ (3) j50 ° C to 90 ° C ... As the temperature rises, except for the reduction of gas

能力提南外，還原反應本身之平衡亦偏向於低價數金屬，故產物中已無氧化亞鐵存在，並且部份氧化鋅亦被還原為金屬，在蒸發後由氣流帶離；隨著BoutJouard反應的降低’碳化鐵之生成量亦隨溫度升高而明顯減少。 (4)同於或等於95 0 °C :在此高溫下，一氧化碳氣體本身於短時間進行Boudouard反應有限，還原力不受損，而還原反應亦偏向金屬態，故可將鋅鐵離子全數還原為金屬。又此溫度已高於鋅之沸點（9 〇 3它），故辞可盡數蒸發並由氣流帶離系統，更加強整個系統之不平衡性。碳化鐵含量則降至1 %以下。In addition to the ability to raise the south, the balance of the reduction reaction itself is also biased towards low-priced metals, so no ferrous oxide exists in the product, and some zinc oxide has also been reduced to metal, which is carried away by the gas stream after evaporation; with BoutJouard Decrease in reaction 'The amount of iron carbide produced also decreases significantly with increasing temperature. (4) Identical to or equal to 95 0 ° C: At this high temperature, the carbon monoxide gas itself has a limited Boudouard reaction for a short period of time, the reducing power is not damaged, and the reduction reaction is also biased to the metal state, so all zinc and iron ions can be reduced. For metal. This temperature is already higher than the boiling point of zinc (903), so it can evaporate as much as possible and be taken away from the system by the airflow, which further strengthens the imbalance of the entire system. The iron carbide content fell below 1%.

。緣此，本發明所運用還原處理之最佳條件，為溫度在 95 0 °C左右之一氧化碳氣流中進行還原反應。電孤爐集塵灰中除鋅鐵氧化物外，成份較高之雜質為氧化鉛、氣化鉛、氣化鈉及氯化鉀，X光繞射光譜儀分析 (XRD )結果，如第二圖所示，這些化合物共同特點為低. For this reason, the optimal condition for the reduction treatment used in the present invention is to perform the reduction reaction in a carbon oxide gas stream at a temperature of about 95 ° C. In addition to zinc iron oxide in the dust collection ash of the electric furnace, the higher impurities are lead oxide, lead gasification, sodium gasification, and potassium chloride. The X-ray diffraction spectrometer analysis (XRD) results, as shown in the second figure As shown, these compounds share a common low

第15頁 200530405 ' 1 五、發明說明（10) J均低於90 0 c ’請參照表二所列述電弧爐含辞集塵 ΐ ΐί要!:合物之融、彿點），在高於此溫度之氣流 σ利用系統之非平衡狀態將其蒸發去除之。性相ίϊ明人遂將此—結果與集塵灰中所含其他雜質之特法相、，…4 ’進而利用以還原法為基底之本發明回收方本申凊專利之標的包括：化物高溫前處理，將電弧爐集塵灰中所含之鉛及氯物除，以提高最終產物之純度；_之固態產粉體开彡々大晶石與虱化辞之混合物，廢氣經冷卻後，可以物。/工收集蒸發之氧化鉛/氣化鉛/氯化鹼金屬等混合用—2」將，處理後之電弧爐集塵灰全還原至金屬態，並使之捭ί 1匕碳氣體為還原劑，使蒸發出之金屬辞在具還原力而：：兰？中（一氧化碳）’呆持其金屬態而不被氧化，進 w收尚純度金屬辞。鐵焯有效避免鐵之熔融，處理溫度降至約950 °c，使疋、、、口為可回收再利用之海綿鐵。業隼鹿=月之主要特徵，其係在提供一種回收電弧爐煉鋼 Λ内所含有價金屬之方法，其步驟為·· (一）造粒及篩選；含之(錯—ί卜)人去除雜質之前處理：在約95〇°c下將集塵灰中所得為合物及氣化鹼金屬鹽類之雜質去除，前處理後所辞及辞鐵尖晶石混合物之燒結顆粒，供置於反應第16頁 200530405 五、發明說明（11) 室進行下一步驟岸室V一，)伴還括原*處:里：使用-氧化碳氣體為還原劑導“ 9 5 0 C，可使鑪不炫又1兮馮約载个^㉚而燒結成海綿鐵； (四）冷凝：反應氣體流出反應室後，即凝，藉由約為9 5 0 °C下夯、古士〆v山/ 進订快速冷卜虱流中一氧化碳/二氧化础+ τ 成份比（99 ·· 1 )可經快诘八細、士位六地立之平衡 ,^ ^ 呎連冷部被保存，避免過高之一一 T辰度造成鋅之再氧化；以及，'經蒸發並由一氧化化払出之金屬鋅在經快速冷卻後，凝結成金屬鋅粉末，二流於集塵設備收集。了便【實施方式】有關本發明為達預期之功效及目的，茲舉出較佳之實施例詳加說明如下：仃貫先，請配合參閱第四圖所示，本發明所提供之流程主要包括造粒及過篩、去除雜質之前處理、還原及冷凝等步驟：里Page 15 200530405 '1 V. Description of the invention (10) J are less than 90 0 c' Please refer to the arc furnace containing the vocabulary of dust collection in Table II. The air stream σ at this temperature is removed by evaporation of the system in an unbalanced state. The sex phase 将此 Ming people then took this—the result is related to the special method of other impurities contained in dust ash, ... 4 ', and then used the reduction method-based recovery method of the present invention as the subject of the patent claim includes: high temperature pre-treatment of the compound, The lead and chlorine contained in the electric arc dust collecting ash are removed to improve the purity of the final product; the solid powder-producing mixture is a mixture of large crystals and lice, and the exhaust gas can be used after cooling. Collecting evaporated lead oxide / lead gaseous lead / alkali chloride and other mixed materials— "2" will reduce the dust collected from the arc furnace to a metallic state after treatment, and use 1 d of carbon gas as a reducing agent. , So that the evaporated metal words have a reducing power :: Lan? Medium (carbon monoxide) 'stays in its metal state without being oxidized, and the metal purity is recovered. Iron grate effectively prevents the melting of iron, and the processing temperature is reduced to about 950 ° c, so that gall, iron, and iron are recyclable sponge iron. The main feature of industry 隼鹿 = month is to provide a method for recovering valence metals contained in electric arc furnace steelmaking Λ. The steps are: (1) granulation and screening; Pre-treatment to remove impurities: The impurities obtained as dust and gasified alkali metal salts in the dust collection ash are removed at about 95 ° C, and the sintered particles of the iron-spinel mixture after the pre-treatment are disposed. In the reaction, page 16, 200530405 V. Description of the invention (11) The next step is to proceed to the bank V1). The original part is also included: inside: using-carbon oxide gas as the reducing agent to guide "9 5 0 C, can make The furnace does not dazzle and sinters, and Feng Yue sinters it into sponge iron; (4) Condensation: The reaction gas condenses after flowing out of the reaction chamber. Set the carbon monoxide / basic dioxide + τ component ratio (99 ·· 1) in the fast cold lice stream, which can be balanced by the speed of eight fines and six positions. ^ ^ Feet even the cold part is saved to avoid excessively high One-to-three degrees of zinc cause re-oxidation of zinc; and, 'The metal zinc that has evaporated and is scavenged from the monoxide is condensed into gold after rapid cooling. Zinc powder is collected in the dust collection equipment. [Embodiment] For the purpose of the present invention to achieve the desired effect and purpose, the preferred embodiment is described in detail as follows: First, please refer to the fourth figure It is shown that the process provided by the present invention mainly includes the steps of granulation and sieving, treatment before removing impurities, reduction and condensation:

(一）造粒及筛選·為避免在處理流程中因通過氣體、生成粉塵逸散’確保工作人員之健康與安全，及避免尾氣$ 煙塵含量過南而影響產物純度，電弧爐集塵灰首先需進行造粒；而傳統之造粒設備無需經過特別改裝即可於此步= 中使用，由於集塵灰内已s含氣化物鹽類，故於造粒過程中無需加入任何結合劑，且集塵灰為平均粒徑約1至i 0 # m 之粉體，可不經研磨直接進行造粒；倘以造粒盤進行造粒時，其操作條件最好是：(I) Granulation and screening · In order to avoid the dissipation of gas and dust during the processing process to ensure the health and safety of workers, and to avoid the exhaust gas content exceeding the south, which will affect the product purity, the arc furnace dust collection ash Granulation is required first; traditional granulation equipment can be used in this step without special modification. Since the dust collecting ash already contains gaseous salts, there is no need to add any binder during the granulation process. And the dust collecting ash is a powder with an average particle diameter of about 1 to i 0 # m, which can be directly granulated without grinding; if the granulation disk is used for granulation, the operating conditions are preferably:

200530405 五、發明說明（12) 1·造粒盤傾角：35至40度； 2.造粒盤轉速：約40轉/分鐘； 3 ·喷水量/速率··依造粒盤大小及物流量不同而定，成粒之含水率需控制在1 0 %左右。所產生之顆粒大小需控制在5到1 〇 m m，以同時兼顧後續給料及反應性，故於造粒步驟後須加以篩選控制，過細顆粒將被導回前一步驟繼續造粒，過粗顆粒則須經破碎後導回造粒步驟。 (一）去除雜質之刖處理··為確保處理後最終產物之純度’有必要在取得鋅鐵金屬前，先行去除集塵灰中所含之錯化合物及氯化驗金屬鹽類等雜質；此步驟為利用鉛化合物及氯化鹼金屬鹽類低融點之特性，在9 5 〇 t下將其自集塵灰中去除，又，為避免鋅在此一步驟中散失，'故以導入空氣流方式將反應氣氛控制在氧化條件下，使鋅與疋保持在尚氧化狀態。 1 藉由空乳流所攜出之鉛化合物及氣化鹼金屬鹽類 ΐϊϊΐ在冷卻設備中凝結為粉塵狀混合物，後經由集肩 5又備收集之；前處理後之固態剩餘物為氧化辞及鋅鐵” 石混合物之燒結顆粒’具有高硬度及高結晶度，可】: 入下一個處理程序；XRD晶相分析結果如接y 處理(前-之Λ:相較’可明確看出上述雜質一均已遭不去除與 (一）還原處理：此程序為以一之還原步驟；其係棚。C之反應溫度下劑尖晶石分別被還原為金屬態；由於反應溫纟（9二)1 200530405 五、發明說明（13) 於金屬鋅之沸點（9 〇 3它），鋅蒸發為氣體並由一氧化碳還原氣體流攜出，此時氣流中尚含有大量還原氣體一氧化碳’可保存辞之金屬態，一氧化碳氣流流速須加以控制，為避免在9 5 0 °C下一氧化碳轉化為二氧化碳及固態碳，一者因氣體中過量之二氧化碳會造成金屬鋅之再氧化，再者所生成之固態碳沉積物會影響到產出之海綿鐵成份。氣體停留時間以在1秒内最佳。 (四）鋅蒸氣冷凝收集：富含鋅蒸氣之還原氣體流出反應室後’即進行快速冷凝步驟，其作用有下列兩點：200530405 V. Description of the invention (12) 1. The inclination angle of the granulating disc: 35 to 40 degrees; 2. The rotating speed of the granulating disc: about 40 rpm; 3; the water spray rate / rate; Differently, the moisture content of granulation needs to be controlled at about 10%. The size of the generated particles needs to be controlled at 5 to 10mm to take into account the subsequent feeding and reactivity. Therefore, after the granulation step, it must be screened and controlled. The ultra-fine particles will be led back to the previous step to continue granulation, and the coarse particles It must be guided back to the granulation step after crushing. (I) Removal of impurities ... To ensure the purity of the final product after the treatment, it is necessary to remove impurities such as the wrong compounds and chlorinated metal salts contained in the dust collection ash before obtaining zinc iron metal; this step In order to take advantage of the low melting point characteristics of lead compounds and alkali metal chloride salts, it was removed from the dust collection ash at 950 t, and in order to avoid the loss of zinc in this step, 'so the introduction of air flow In this way, the reaction atmosphere is controlled under oxidizing conditions, so that zinc and osmium are kept in a state of oxidation. 1 The lead compounds and gasified alkali metal salts carried by the empty milk stream are condensed into a dusty mixture in a cooling device, and then collected by the shoulder 5; the solid residue after pretreatment is oxidized And zinc-iron "stone mixture sintered particles 'has high hardness and high crystallinity, can be]: Enter the next processing program; XRD crystal phase analysis results such as y treatment (front-of Λ: compared to' can clearly see the above Impurities have not been removed and (a) reduction treatment: This procedure is a reduction step of one; it is a shed. At the reaction temperature of C, the spinel is reduced to a metal state; ) 1 200530405 V. Description of the invention (13) At the boiling point of zinc metal (903), zinc evaporates into a gas and is carried out by a stream of carbon monoxide reducing gas. At this time, the gas stream still contains a large amount of reducing gas carbon monoxide. In the metallic state, the flow rate of carbon monoxide must be controlled. In order to avoid the conversion of carbon monoxide to carbon dioxide and solid carbon at 950 ° C, one of the excess carbon dioxide in the gas will cause the reoxidation of zinc metal. The formed solid carbon deposits will affect the sponge iron content produced. The gas retention time is best within 1 second. (4) Zinc vapor condensation collection: After the reducing gas rich in zinc vapor flows out of the reaction chamber, it will be quickly performed. The condensation step has the following two functions:

一 1 · 9 5 0 c下氣流中一氧化碳/二氧化碳之平衡成份比可經快速冷卻被保存，避免過高之二氧化碳濃度造成辞之再 2.經蒸發並由一卻後，凝結成金屬鋅如第四圖所示之後’因斜化合物及氯應用旋風離心設備或【處理成效】依本發明方法，五圖所示，以本發明可達到下列重要成效氧化碳氣流攜出之金屬鋅在經快速冷粉末，可以集塵設備收集之。處理流程内，前處理後及其冷凝步驟化鹼金屬鹽類均凝結為粉體，故均可袋式集塵設備來進行收集。每1000kg集塵灰進料之質量平衡如第之流程進行電弧爐含辞集塵灰處理， (一）高回收率中99.9%之含辞量加為海錦鐵’可直接用 .依本發明流程，可將電弧爐集塵灰以金屬化並回收；含鐵量則全數燒結為煉鋼業之二次原料；經前處理收集The balance ratio of carbon monoxide / carbon dioxide in the down stream of 1 · 9 5 0 c can be stored by rapid cooling to avoid excessive carbon dioxide concentration. 2. After evaporation and coagulation, it will condense into metal zinc as the first After the four figures are shown, the cyclone centrifuge equipment or [treatment effect] is used for the oblique compounds and chlorine. According to the method of the present invention, as shown in the fifth figure, the following important effects can be achieved by the present invention: Powder can be collected by dust collection equipment. In the treatment process, after the pretreatment and its condensation steps, the alkali metal salts are condensed into powder, so they can be collected by bag dust collection equipment. The mass balance of the feed per 1000kg of dust-collecting ash is as described in the first process, and the dust-collecting ash is processed in the electric arc furnace. (1) The 99.9% content in the high recovery rate is added to the sea bromine iron, which can be used directly. The process can metallize and recover the dust collected from the electric arc furnace. The iron content is fully sintered as a secondary raw material for the steelmaking industry.

200530405 五、發明說明（14) 之鹵化物/鉛化物混合粉體，則可視成份、量及經濟效益’加以淨化而回收鉛，氯化物部份則可再生為鹽類製程之原料；共計至少可將電弧爐集塵灰中超過9 5 %之有價金屬資源化。 (一）而去除率：氧化條件下之蒸發前處理步驟，可對錯化物及氯化物鹽類達到95%以上之去除率，大幅提高最終產物純度。 (二）鬲純度產物：本流程之主要產物為金屬辞及海綿鐵； a·金屬辞粉之純度平均超過99· 5 %，内僅含少量之鉛 (<〇·4%)及微量氧化鋅（<〇〇5%)，金屬化比率超過99· 9/6 了直接用於防銹嗔塗’或進入精煉廠’用以生產高價值面純度之鋅製品，可提供更高階用途。 b·海綿鐵之含鐵量平均在9〇 %以上，Boud〇uard反應所產生之元素碳約佔4 %左右，因此除金屬鐵外，尚含約 10 %之碳化鐵，金屬化比率約在9〇 %，可回收至煉鋼業作為二次原料。 (四）低污染危險··在本流程中氣及碳之物流被分離亦即先以鍛燒前處理進行除氣後，再導入含碳之還原 ^ 大巾曰降低兩者接觸機會，所產生之廢氣並可經過後燃，有效降低生成戴奥辛之危險性；並且，集塵灰在進料前先經過造粒步驟，可有效避免主流程氣流中灰塵之產生’確保工作人員安全與尾氣品質。 (五）節省能源及提高有價金屬之品質：本發明將去200530405 V. Description of the invention (14) For the halide / lead compound powder, lead can be recovered based on its composition, amount and economic benefits, and the chloride part can be regenerated as raw materials for the salt process; Recycling more than 95% of the valuable metals in the arc furnace dust. (1) And the removal rate: The pre-evaporation treatment step under oxidation conditions can achieve a removal rate of more than 95% for complex compounds and chloride salts, which greatly improves the purity of the final product. (II) Purity products: The main products of this process are metal ions and sponge iron; a. The purity of metal powder is over 99.5% on average, which contains only a small amount of lead (< 0.4%) and a small amount of oxidation. Zinc (< 0.05%), metallization ratio exceeding 99 · 9/6, used directly for anti-rust coating or entering refinery to produce zinc products with high value surface purity, which can provide higher-level applications. b. The iron content of sponge iron is more than 90% on average, and the elemental carbon produced by Boudouard reaction accounts for about 4%. Therefore, in addition to metallic iron, it also contains about 10% of iron carbide. The metallization ratio is about 90%, can be recycled to the steelmaking industry as a secondary raw material. (4) Low pollution risk · In this process, the gas and carbon streams are separated, that is, the degassing is carried out before the calcination process, and then the carbon-containing reduction is introduced. The exhaust gas can be post-combusted, which effectively reduces the risk of dioxin formation. Moreover, the dust collecting ash goes through the granulation step before feeding, which can effectively avoid the generation of dust in the main process air flow, ensuring the safety of workers and the quality of exhaust gas. (5) Save energy and improve the quality of valuable metals: The present invention will

第20頁 200530405 五、發明說明（15) 除雜質之前處理溫度控制為約9 5 0 °C，不僅可先行去除集塵灰中所含之鉛化合物及氯化驗金屬鹽類等雜質，更可確保處理後最終產物之純度，而在還原處理時仍控制反應溫度約在9 5 0 °C ’以使氧化鋅及鋅鐵尖晶石分別被還原為金屬態；如此’將前處理及還原反應之溫度控制在約為9 5 〇 C，並藉由一氧化碳為還原劑，相較於傳統高溫冶煉，應用焦厌還原法在超過1 2 0 0 C溫度下對鋅進行回收之技術，本發明可減少大量燃料能源之耗費’且更有效蒐集高純度金屬鋅。 (六）挺南產業之經濟效益··本發明之流程若内建於電弧爐煉鋼廠内，可直接使用轉爐產生之一氧化碳廢氣作為還原劑，不僅可節省處理成本，更可將製程尾氣直接再利用，減輕廢氣處理單元之負擔，確保排氣品質，兼具南效能與節省成本之功效。綜上所述’本發明實施例確實已能達到所預期之目及功效，且未見有相同特徵者公開在先，故本發明合处^ 合發明專利之申請要件，爰依法提出申請，懇請早==付結，並核賜專利，實深任感荷。Page 20 200530405 V. Description of the invention (15) The processing temperature before removing impurities is controlled to about 950 ° C, which can not only remove impurities such as lead compounds and chlorinated metal salts contained in dust collection ash, but also ensure that The purity of the final product after the treatment, and the reaction temperature is still controlled at about 950 ° C during the reduction treatment, so that the zinc oxide and zinc iron spinel are reduced to the metal state respectively; in this way, the pretreatment and reduction reactions The temperature is controlled at about 950C, and by using carbon monoxide as a reducing agent, compared with the traditional high-temperature smelting, the technology of recovering zinc at a temperature exceeding 12000C by using the coke anaerobic reduction method, the present invention can reduce Consumption of a large amount of fuel energy 'and more efficient collection of high-purity zinc metal. (VI) Economic Benefits of Tingnan Industry ... If the process of the present invention is built in an electric arc furnace steelmaking plant, the carbon monoxide exhaust gas generated by the converter can be directly used as a reducing agent, which can not only save processing costs, but also directly process the tail gas. Reuse reduces the burden on the exhaust gas treatment unit and ensures the quality of the exhaust gas. In summary, the embodiments of the present invention have indeed achieved the expected purpose and effect, and no one with the same characteristics has been disclosed before. Therefore, the present invention is co-located with the application requirements of the invention patent. Earlier == pay the knot and grant the patent.

200530405 圖式簡單說明 ~ 【圖式簡單說明】第一圖所示係為鋅鐵尖晶石進行還原反應產物對溫度變化之相位圖。第二圖所示係為未經去除雜質處理之電弧爐含鋅集塵灰之 X光繞射光譜分析。 /、第三圖所不係為經前處理後之電弧爐含鋅集塵灰之义光繞射光譜分析。第四圖所示係為本發明之基本流程圖。【附件】、係為辞—鐵-氧三元系統於1 20 0 K之相位圖參第五圖所示係為本發明處理流程之質量平衡圖。200530405 Simple illustration of the drawing ~ [Simplified illustration of the drawing] The first picture shows the phase diagram of the reduction reaction product of zinc iron spinel as a function of temperature. The second figure shows the X-ray diffraction spectrum analysis of zinc-containing dust collected in the electric arc furnace without the impurity removal treatment. / 、 The third figure does not show the analysis of the light diffraction spectrum of the zinc furnace dust containing ash after the pretreatment. The fourth figure shows a basic flowchart of the present invention. [Annex] is the phase diagram of the iron-oxygen ternary system at 1,200 K. Refer to the fifth figure for the mass balance diagram of the processing flow of the present invention.

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Claims

200530405 六、申凊專利範圍 1 ·本發明係一種回收電弧爐煉鋼業集塵灰内所含有價金屬之方法，其步驟為： (一）造粒及篩選；入（二）去除雜質之前處理··在約9 5 0 °C下將集塵灰中所 ;$，$合物及氯化驗金屬鹽類之雜質去除，前處理後所 :進=辞及辞鐵尖晶石混合物之燒結顆粒，供置於反應主疋订下一步驟；室中(三if原處理：使用一氧化碳氣體為還原劑導入反應。 ”寺金屬鋅之穩定，同時還原處理溫度降為約9 5 0 ’可使鐵不熔融而燒結成海綿鐵； (二）冷凝：反應氣體流出反應室後，即進行快速冷成份= SH95(rc下氣流中一氧化碳/二氧化碳之平衡 =(99:1)可經快速冷卻被保存，避免過高之二氧化二：度造成鋅之再氧化；以及，、經蒸發並由一氧化碳氣流二I^金屬鋅在經快速冷卻後，凝結成金屬鋅粉末，可便於集塵設備收集。 j便 I^如申请專利範圍第1項所述一種回收電弧爐煉鋼举二有價金屬之方法，…驟-造粒之產二位玻好控制在5到i〇mm。 3如申請專利範圍第丨項所述一種回收電弧爐煉鋼 ^ Λ =所含有價金屬之方法，其中以造粒盤進行造粒、燄、i其操作條件最好是：造粒盤傾角：35至40度、造粒盤泣j ·約4 0轉/分鐘以及喷水量/速率：依造粒盤大小及机I不同而定，成粒之含水率需控制在丨〇%左右。200530405 VI. Application scope of patent 1. The present invention is a method for recovering valence metals contained in dust collection ash of EAF steelmaking industry. The steps are: (1) granulation and screening; (2) treatment before removing impurities Remove the impurities in the dust collection ash at about 950 ° C; the impurities of $, $ compound and chlorinated metal salts are removed, and after the pretreatment: the sintered particles of the mixture of iron and spinel spinel For the next step in the main reaction chamber; in the chamber (original treatment: the carbon monoxide gas is used as the reducing agent to introduce the reaction. "The stability of the metal zinc is reduced, and the temperature of the reduction treatment is reduced to about 9 5 0 'can make iron It does not melt and sinters into sponge iron; (2) Condensation: After the reaction gas flows out of the reaction chamber, it is rapidly cooled. The composition = SH95 (carbon monoxide / carbon dioxide balance in the air stream under rc = (99: 1) can be stored by rapid cooling. Avoid excessively high levels of dioxide: reoxidation of zinc; and, after being rapidly cooled, the carbon dioxide monoxide will be condensed into metal zinc powder, which can facilitate the collection of dust collection equipment. I ^ If you apply for a patent A method for recovering two valuable metals in electric arc furnace steelmaking as described in item 1, ...-the granulation output is controlled to 5 to 10 mm. 3 A kind of recovery as described in item 丨 of the scope of patent application Electric arc furnace steelmaking ^ Λ = method of containing valence metals, in which the granulation disk is used for granulation, flame, and i. The operating conditions are preferably: the granulation disk inclination angle: 35 to 40 degrees, the granulation disk weeping 40 revolutions per minute and water spraying rate / rate: depending on the size of the granulation disc and the machine I, the moisture content of the granulation needs to be controlled at about 0%.

第23頁 200530405 六、申請專利範圍 - 4.如申請專利範圍第1項所述一種回收電弧爐煉麵業集塵灰内所含有價金屬之方法，其中造粒步驟後須加以、筛選控制’過細顆粒將被導回造粒步驟繼續進行造粒，广阳過粗顆粒則須經破碎後導回造粒步驟。 5 ·如申請專利範圍第1項所述一種回收電弧爐煉鋼業集塵灰内所含有價金屬之方法，其中在去除雜質之前處'理時，需以導入空氣流方式將反應氣氛控制在氧化條件下，使鋅與鐵穩定保持在高氧化狀態。 6 ·如申請專利範圍第5項所述一種回收電弧爐煉鋼業集塵灰内所含有價金屬之方法，其中由空氣流攜出之錯化合物及氣化鹼金屬鹽類蒸氣在冷卻設備中凝結為粉塵狀混合物，後經由集塵設備收集之。此 7·如申請專利範圍第1項所述一種回收電弧爐煉鋼業集塵灰内所含有價金屬之方法，其中在步驟三當辞蒸發為氣體並由氣流攜出，此時氣流中尚含有大量還原氣體一氧化碳，可保存鋅之金屬態，一氧化碳氣流流速須加以控制，氣體在反應區之停留時間需在1秒内。 8·如申請專利範圍第丨項所述一種回收電弧爐煉鋼業集塵灰内所含有價金屬之方法，其中在去除雜質之前處理及還原處理時之溫度最好控制在9 4 5 I〜9 5 5。Page 23 200530405 VI. Scope of patent application-4. As described in item 1 of the scope of patent application, a method for recovering valence metals contained in the dust collection ash of the electric arc furnace noodle industry, after which the granulation step must be controlled by screening 'The over-fine particles will be guided back to the granulation step to continue the granulation, and the Guangyang over-coarse particles must be broken back to the granulation step. 5 · A method for recovering valence metals contained in the dust collection ash of the electric arc furnace steelmaking industry as described in item 1 of the scope of the patent application, in which the reaction atmosphere needs to be controlled by introducing an air flow during treatment before removing impurities Under oxidation conditions, zinc and iron are stably maintained in a high oxidation state. 6 · A method for recovering valence metals contained in dust collection ash of the electric arc furnace steelmaking industry as described in item 5 of the scope of the patent application, wherein the wrong compounds and vaporized alkali metal salt vapors carried by the air stream are in a cooling device Condensed into a dusty mixture and collected by a dust collection device. 7. A method for recovering valence metals contained in dust collection ash of the electric arc furnace steelmaking industry as described in item 1 of the scope of the patent application, wherein in step three, the distillate evaporates to a gas and is carried out by a gas stream. Contains a large amount of reducing gas carbon monoxide, which can save the metallic state of zinc. The flow rate of the carbon monoxide gas stream must be controlled, and the residence time of the gas in the reaction zone must be within 1 second. 8 · A method for recovering valence metals contained in the dust collection ash of the electric arc furnace steelmaking industry as described in item 丨 of the scope of the patent application, wherein the temperature before the removal of impurities and the reduction treatment is preferably controlled at 9 4 5 I ~ 9 5 5.