JP5065732B2 - Method for recovering indium from display panel - Google Patents
Method for recovering indium from display panel Download PDFInfo
- Publication number
- JP5065732B2 JP5065732B2 JP2007086956A JP2007086956A JP5065732B2 JP 5065732 B2 JP5065732 B2 JP 5065732B2 JP 2007086956 A JP2007086956 A JP 2007086956A JP 2007086956 A JP2007086956 A JP 2007086956A JP 5065732 B2 JP5065732 B2 JP 5065732B2
- Authority
- JP
- Japan
- Prior art keywords
- indium
- glass
- display panel
- fine powder
- recovering
- 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 - Fee Related
Links
- 229910052738 indium Inorganic materials 0.000 title claims description 58
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 title claims description 57
- 238000000034 method Methods 0.000 title claims description 31
- 239000011521 glass Substances 0.000 claims description 55
- 239000000843 powder Substances 0.000 claims description 19
- 238000010298 pulverizing process Methods 0.000 claims description 15
- 239000002245 particle Substances 0.000 claims description 8
- 239000004576 sand Substances 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 6
- 238000000638 solvent extraction Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000010306 acid treatment Methods 0.000 claims description 2
- 238000000605 extraction Methods 0.000 claims description 2
- 238000000746 purification Methods 0.000 claims description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 18
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 14
- 229910052751 metal Inorganic materials 0.000 description 10
- 239000002184 metal Substances 0.000 description 10
- 238000004064 recycling Methods 0.000 description 7
- 238000003723 Smelting Methods 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 239000002904 solvent Substances 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 239000011362 coarse particle Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 239000010409 thin film Substances 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 239000006063 cullet Substances 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000010008 shearing Methods 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- 239000011701 zinc Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000011001 backwashing Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 238000005477 sputtering target Methods 0.000 description 2
- 229910052718 tin Inorganic materials 0.000 description 2
- ZDFBXXSHBTVQMB-UHFFFAOYSA-N 2-ethylhexoxy(2-ethylhexyl)phosphinic acid Chemical compound CCCCC(CC)COP(O)(=O)CC(CC)CCCC ZDFBXXSHBTVQMB-UHFFFAOYSA-N 0.000 description 1
- HZIUHEQKVCPTAJ-UHFFFAOYSA-N 3-(2-ethylhexoxyphosphonoyloxymethyl)heptane Chemical group CCCCC(CC)COP(=O)OCC(CC)CCCC HZIUHEQKVCPTAJ-UHFFFAOYSA-N 0.000 description 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 1
- 239000005388 borosilicate glass Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 239000008151 electrolyte solution Substances 0.000 description 1
- 238000005363 electrowinning Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- -1 ferrous metals Chemical class 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 238000009854 hydrometallurgy Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- CVNKFOIOZXAFBO-UHFFFAOYSA-J tin(4+);tetrahydroxide Chemical compound [OH-].[OH-].[OH-].[OH-].[Sn+4] CVNKFOIOZXAFBO-UHFFFAOYSA-J 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Manufacture And Refinement Of Metals (AREA)
- Electrolytic Production Of Metals (AREA)
Description
本発明は、液晶ディスプレー,ELディスプレー、プラズマディスプレーなどのパネル中の透明電極に含有されるインジウムを回収する方法に関するものである。以下主として液晶ディスプレーのパネルについて説明する。 The present invention relates to a method for recovering indium contained in a transparent electrode in a panel such as a liquid crystal display, an EL display, or a plasma display. The liquid crystal display panel will be mainly described below.
液晶ディスプレーデバイスのパネルは、液晶を中心としてこれを挟むサンドイッチ構造を有しており、液晶の両側に配置される基本的部材は、薄膜トランジスタ、ITO透明電極、ガラス基板及び樹脂からなる偏光膜である。さらに金属クロムからなる反射防止膜などが設けられることもある。ディスプレーパネルのリサイクルの観点からは、最も多いガラス基板をどのように再利用するかが重要であり、一方ITO透明電極は重量割合で極めて少ないが、資源が非鉄金属中でも少ないインジウムを含有しているので、インジウムのリサイクルも同様に重要である。
ELディスプレーデバイスは液晶デバイスの一種であるが、陽極にITO透明電極が用いられている。
また、プラズマディスプレーにおいては、デバイス前面のガラス基板の裏にITO透明電極が配置されている。これらのディスプレーデバイスのパネルにおいてもガラスが圧倒的割合を占め、ITO透明電極の割合は僅かである。
The panel of a liquid crystal display device has a sandwich structure sandwiching the liquid crystal as a center, and the basic members arranged on both sides of the liquid crystal are a thin film transistor, an ITO transparent electrode, a glass substrate and a polarizing film made of a resin. . Further, an antireflection film made of metallic chromium may be provided. From the viewpoint of display panel recycling, it is important how to reuse the most glass substrates, while ITO transparent electrodes contain very small amounts of indium, even though the resources are non-ferrous metals. So recycling indium is equally important.
An EL display device is a type of liquid crystal device, but an ITO transparent electrode is used for the anode.
In the plasma display, ITO transparent electrodes are arranged behind the glass substrate on the front of the device. In these display device panels, glass accounts for an overwhelming percentage, and the percentage of ITO transparent electrodes is small.
ところで、世界で産出するインジウムのほとんどは液晶ディスプレーデバイスの透明電極に使用されており、一方では地球上のインジウム資源の量は限られているので、使用済み廃棄されるディスプレーデバイス及びディスプレーデバイス製造工程で廃棄されるディスプレーパネルなどはまさに都市鉱山である。以下、主に液晶ディスプレーデバイスのリサイクルに関する従来技術を説明する。 By the way, most of the indium produced in the world is used for transparent electrodes of liquid crystal display devices. On the other hand, the amount of indium resources on the earth is limited. The display panels that are discarded in the city are just urban mines. In the following, conventional techniques relating to recycling of liquid crystal display devices will be mainly described.
特許文献1:特開2000−84531号公報は、液晶工場から出てくる廃液晶ーパネルを、液晶を含んだ状態で、1軸剪断式破砕機により処理して例えば5mm程度まで粉砕して得たガラスカレットを約1200℃の非鉄精錬炉に投入することを提案する。ガラスカレットは非鉄精錬炉において鉄を除去する精錬剤として利用される。回収物としてはインジウムについては特に述べられていないが、1200℃の非鉄製錬炉で乾式製錬された後の湿式精錬工程で回収することは可能である。 Patent Document 1: Japanese Patent Laid-Open No. 2000-84531 was obtained by treating a waste liquid crystal panel coming out of a liquid crystal factory with a uniaxial shearing type crusher in a state containing liquid crystal and crushing it to about 5 mm, for example. It is proposed to put glass cullet into a non-ferrous smelting furnace at about 1200 ℃. Glass cullet is used as a refining agent for removing iron in a non-ferrous smelting furnace. Although indium is not particularly described as a recovered material, it can be recovered in a hydrometallurgical process after dry smelting in a non-ferrous smelting furnace at 1200 ° C.
特許文献2:特開2001―236718号公報では、先ず、プラスチックや金属に分別されない液晶パネルを超臨界反応器で分解、溶解する。超臨界溶媒はエタノールなどであり、超臨界条件としては、温度773K, 圧力35Mpaが例示され、インジウムは超臨界流体に溶解する。超臨界反応器の処理での未分解の固体は固体補修室で回収する。超臨界反応器で溶媒に溶解した液体は、冷却しディスプレーパネル中の固体成分を析出させ、生成物を減圧し分解槽に送る。クロム、ヒ素、鉛などの有害と考えられる金属及びインジウムは超臨界溶媒に一旦溶解し、その後固体として回収され、既存の金属製錬工程で処理する。またガラスカレットが回収される。 Patent Document 2: In Japanese Patent Laid-Open No. 2001-236718, first, a liquid crystal panel that is not separated into plastic or metal is decomposed and dissolved in a supercritical reactor. The supercritical solvent is ethanol or the like, and the supercritical conditions include a temperature of 773 K and a pressure of 35 Mpa, and indium dissolves in the supercritical fluid. Undecomposed solids from the supercritical reactor process are collected in the solid repair room. The liquid dissolved in the solvent in the supercritical reactor is cooled to precipitate solid components in the display panel, and the product is decompressed and sent to the decomposition tank. Metals that are considered harmful such as chromium, arsenic, lead, and indium are once dissolved in a supercritical solvent, and then recovered as a solid, which is processed in an existing metal smelting process. Glass cullet is collected.
特許文献3:特開2001−296508号公報は、廃液晶パネルを次の工程により処理することを提案している。(1)蛍光X線分析法によって,ソーダガラス、アルミのホウケイ酸ガラスなどのガラス種類を選別する。(2)選別されたガラス種類毎に以下の処理を行う。まず、ディスプレーパネルを燃焼させて、シール樹脂、偏光板、カラーフィルタ、配向膜などの有機物を分解する。(3)ガラス基板を含む未燃焼残部をボールミルにより粉砕する。これによりガラス基板の粉砕物とインジウム、クロムなどを多く含む薄膜粉砕物を分離し、金属とガラスを分級することにより別々に回収する。さらに、ガラスは予め品種毎に選別されているから、回収されたガラスはガラス原料として再利用することができる。 Patent Document 3: Japanese Patent Laid-Open No. 2001-296508 proposes to process a waste liquid crystal panel by the following process. (1) Sort glass types such as soda glass and aluminum borosilicate glass by fluorescent X-ray analysis. (2) The following processing is performed for each selected glass type. First, the display panel is burned to decompose organic substances such as a sealing resin, a polarizing plate, a color filter, and an alignment film. (3) The unburned residue including the glass substrate is pulverized by a ball mill. Thereby, the pulverized product of the glass substrate and the pulverized thin film containing a large amount of indium, chromium, etc. are separated and recovered separately by classifying the metal and glass. Furthermore, since the glass is sorted in advance for each type, the recovered glass can be reused as a glass raw material.
ディスプレーパネルのリサイクル法ではないが、特許文献4:特開2002−69544号公報はITOスパッタリングターゲットからのインジウムの回収を、ITOスパッタリングターゲットを塩酸で溶解し、溶液に水酸化ナトリウムを添加してスズを水酸化スズとして除去し、その後インジウムを亜鉛と置換沈澱することを提案している。
これら従来技術を各種ディスプレーパネルの処理に応用した場合について述べる。先ず、特許文献1の方法は、単に粉砕処理のみを行うので工程が簡単であるが、インジウムは乾式製錬だけでは回収されないので、その後の処理が必要となり、また、提案された粉砕法だけではガラスを回収しリサイクルすることはできない。
次に、特許文献2の方法は、高圧・高温が必要であり、また溶媒としてエタノールなどが必要であるためにコストが高くなる。
最後に、特許文献3の方法では、インジウムなどの金属をガラスから剥離するためには、かなりの程度の粉砕を進行する必要があり、この結果、回収されるガラスは微粉になり、土木砂代替材料としてはリサイクルできない懸念がある。
The case where these conventional techniques are applied to processing of various display panels will be described. First, the method of Patent Document 1 is simple because only the pulverization process is performed. However, since indium is not recovered only by dry smelting, subsequent processing is necessary, and only the proposed pulverization method is used. Glass cannot be recovered and recycled.
Next, the method of Patent Document 2 requires high pressure and high temperature, and requires ethanol or the like as a solvent, which increases the cost.
Finally, in the method of Patent Document 3, in order to peel a metal such as indium from the glass, it is necessary to proceed to a considerable degree of pulverization. As a result, the recovered glass becomes a fine powder, replacing civil engineering sand. There is concern that it cannot be recycled as a material.
土木工事の砂は、砂の粒度が微細すぎると、粉塵が発生しまた雨水で流出などの問題が起こる。一方、粒度が粗すぎるとガラスそのものであり適していない。さらに、砂の形状はできるだけ丸みを帯びていることが望ましい。ところで、特許文献1〜3で提案されているディスプレーパネルのリサイクル法は特に土木工事の砂として再生することを意図していない。 If the sand used in civil engineering works is too fine, dust will be generated and rainwater will cause problems such as runoff. On the other hand, if the particle size is too coarse, the glass itself is not suitable. Furthermore, it is desirable that the sand shape be as round as possible. By the way, the recycling method of the display panel proposed in Patent Documents 1 to 3 is not particularly intended to be regenerated as civil engineering sand.
このような従来技術に鑑み、本発明は、廃棄ディスプレーパネルの透明電極から、エネルギーコストをかけないでインジウムを高回収率で回収し、同時にインジウム濃度が低くかつ適度な大きさのガラスも回収することができる方法を提供することを目的とする。 In view of such prior art, the present invention recovers indium from a transparent electrode of a waste display panel at a high recovery rate without incurring energy costs, and at the same time recovers glass having a low indium concentration and an appropriate size. It aims to provide a method that can be used.
本発明は、主としてガラスからなりかつITO透明電極を含むディスプレーパネルを粉砕し、粉砕物からインジウムを回収する方法において、粉砕物を、250μm の篩目を有する篩を使用して、250μmを超えるガラス粒子と、250μm以下のガラス微粉に分級し、得られた250μm以下の、インジウムが濃縮された前記ガラス微粉からインジウムを回収することを特徴とするディスプレーパネルからのインジウム回収方法を提供するものである。以下、本発明を詳しく説明する。 The present invention relates to a method of pulverizing a display panel mainly made of glass and including an ITO transparent electrode, and recovering indium from the pulverized product, and using a sieve having a 250 μm mesh , the pulverized product is a glass exceeding 250 μm. The present invention provides a method for recovering indium from a display panel, characterized by recovering indium from the particles and the glass fine powder of 250 μm or less obtained by concentration into glass fine powder of 250 μm or less. . The present invention will be described in detail below.
本発明者は、ディスプレーパネルの粉砕物を250μmを境として分級すると、250μm以下の微粉(以下「インジウム濃縮微粉」という)にはインジウムが高濃度に濃縮していることを見出した。即ち、ディスプレーパネル全体に対するインジウム濃度は液晶パネルでは0.01%程度であり、このような低濃度の廃棄物からインジウムを回収することは容易ではないが、本発明によると約10倍インジウムが濃縮したガラスを回収することができるので、ガラスとインジウムを完全に分離しなくとも、インジウムが濃縮したガラスからインジウムを回収することは十分に可能である。また、分級を250μmより粗くすると、微粉中のインジウム濃度が低くなり、回収工程での効率が低下し、一方分級を250μmより微細にすると、篩上物中に残るインジウム量が多くなる。 The present inventor has found that when the pulverized product of the display panel is classified at a boundary of 250 μm, indium is concentrated at a high concentration in a fine powder of 250 μm or less (hereinafter referred to as “indium-concentrated fine powder”). That is, the concentration of indium in the entire display panel is about 0.01% in the liquid crystal panel, and it is not easy to recover indium from such low-concentration waste. Therefore, it is possible to recover indium from the glass enriched with indium without completely separating the glass and indium. If the classification is made coarser than 250 μm, the concentration of indium in the fine powder is lowered, and the efficiency in the recovery process is lowered. On the other hand, if the classification is made finer than 250 μm, the amount of indium remaining in the sieved product increases.
粉砕によりインジウムが濃縮したガラスが得られるのは次のように考えられる。即ち、ディスプレーパネル全体に粉砕力を加えると、図1に示すITO透明電極1と薄膜トランジスタ2で被覆されたガラス表面部3aはインジウム濃縮微粉10となり、一方、かかる表面より内側のガラス基板中心部3bは12になる。液晶4は粉砕の過程でインジウム濃縮微粉10より剥離される。 The reason why a glass in which indium is concentrated by pulverization is obtained is considered as follows. That is, when a crushing force is applied to the entire display panel, the glass surface portion 3a covered with the ITO transparent electrode 1 and the thin film transistor 2 shown in FIG. Becomes 12. The liquid crystal 4 is peeled off from the indium-concentrated fine powder 10 during the pulverization process.
上記したインジウム濃縮微粉10とガラス粗粒12を得るための粉砕は、ディスプレーパネルに回転力を与え粉砕室に衝突させるコーンクラッシャなどの粉砕機により行うことができる。この粉砕機によると、ガラスの界面11(図1参照)に逆方向の剪断力を加えることにより前の段落で説明した粉砕を効率的に行うことができる。好ましくは、粉砕は回転刃により、被処理物に剪断力を与えて一次的に粉砕し、さらに粉砕物どうしが接触して二次的に粉砕を行う。 The pulverization for obtaining the indium-enriched fine powder 10 and the glass coarse particles 12 can be performed by a pulverizer such as a cone crusher that applies a rotational force to the display panel and collides with the pulverization chamber. According to this pulverizer, the pulverization described in the previous paragraph can be efficiently performed by applying a shearing force in the reverse direction to the glass interface 11 (see FIG. 1). Preferably, the pulverization is performed by applying a shearing force to the object to be processed by the rotary blade to perform primary pulverization, and the pulverized products are in contact with each other to perform secondary pulverization.
250μmより粗粒のガラス粒子は土木用砂代替材料として適している。この250μmを境にする分級は振動篩を用いて行うことができる。 Glass particles coarser than 250 μm are suitable as a sand substitute for civil engineering. The classification at the boundary of 250 μm can be performed using a vibrating sieve.
本発明により得られたインジウム濃縮微粉は、その主成分はガラスであり、半導体シリコン、インジウム、スズなどを含有している。インジウム濃縮微粉を酸で処理すると、ガラス及びシリコンは未溶解で残り、インジウムやその他の随伴金属は酸に溶解される。塩酸溶液中のインジウム濃度は一般に200〜300mg/Lである。
続いて、特許文献4が提案するように亜鉛で置換沈澱する方法によってもよいが、インジウムを溶解した溶液を溶媒抽出法によりインジウムを他の金属とは分離して効率的に抽出することが好ましい。その後、塩酸で逆抽出し、塩酸電解浴で電解採取を行い金属インジウムを回収する。電解液のIn濃度50〜60g/l、pH2.0〜2.2、電流密度75〜90A/dm2、液温30〜40℃が好ましい。
以上のところから、本発明の好ましい実施態様は次のとおりである。
The indium-enriched fine powder obtained by the present invention is mainly composed of glass and contains semiconductor silicon, indium, tin and the like. When the indium-enriched fine powder is treated with acid, glass and silicon remain undissolved, and indium and other accompanying metals are dissolved in acid. The concentration of indium in the hydrochloric acid solution is generally 200 to 300 mg / L.
Subsequently, as proposed in Patent Document 4, substitution precipitation with zinc may be used, but it is preferable to efficiently extract indium from other metals by a solvent extraction method from a solution in which indium is dissolved. . Thereafter, back extraction is performed with hydrochloric acid, and electrowinning is performed in a hydrochloric acid electrolytic bath to recover metal indium. The electrolytic solution preferably has an In concentration of 50 to 60 g / l, a pH of 2.0 to 2.2, a current density of 75 to 90 A / dm 2 , and a liquid temperature of 30 to 40 ° C.
From the above, preferred embodiments of the present invention are as follows.
(1)分級された250μmを超えるガラス粒子を土木砂代替材料に使用する方法。
(2)前記ディスプレーパネルを予備解体あるいは焼却することなく粉砕する(1)記載の方法。
(3)前記ガラス微粉を酸で処理し、溶媒抽出、逆洗及び電解精製によりインジウムを回収する(1)又は(2)記載の方法。
(1) A method of using classified glass particles exceeding 250 μm for civil engineering sand substitute materials.
(2) The method according to (1), wherein the display panel is pulverized without preliminary dismantling or incineration.
(3) The method according to (1) or (2), wherein the glass fine powder is treated with an acid, and indium is recovered by solvent extraction, backwashing and electrolytic purification.
(1)本発明法によると、ガラス粗粒は適度の大きさを有し、かつインジウム濃度が低く、ガラス微粒はインジウムが濃縮している。インジウム濃縮ガラス微粉は酸との接触面積が大きく、インジウムを湿式法で効率的に溶解することができる。
(2)ガラス粗粒は適度の大きさを有しているために、土木用に使用した際に粉塵などを発生せずに、道路、堤防などの材料として有効に使用することができる(請求項2)。
(3)ディスプレーパネルの予備解体、予備焼却、高圧処理、溶媒の使用などが一切不必要であるために、リサイクルのためのコストが低く、廃棄ディスプレーパネルをそのままリサイクルすることができる(請求項3)。なお、多少の予備焼却済み又は解体済みディスプレーパネルが混合していても、粉砕の進行状況はほとんど変わらないので、本発明法は処理原料範囲が広い。
(4)インジウムを酸処理、溶媒抽出及び電解処理で高い回収率で回収することができる。また、亜鉛などの還元剤をインジウム回収のために使用しないので、原料コストが低い(請求項4)。
以下、液晶ディスプレーデバイスのパネルを処理した実施例により本発明をさらに具体的に説明するが、ガラスと透明電極を含むその他のパネルも同様に処理できることは理解できるであろう。
(1) According to the method of the present invention, the glass coarse particles have an appropriate size, the indium concentration is low, and the glass fine particles are enriched with indium. The indium-concentrated glass fine powder has a large contact area with an acid, and can dissolve indium efficiently by a wet method.
(2) Since the coarse glass particles have an appropriate size, they can be used effectively as materials for roads, embankments, etc. without generating dust when used for civil engineering. Item 2).
(3) Since there is no need for preliminary disassembly, preliminary incineration, high-pressure treatment, use of solvent, etc., the display panel is low in cost and can be recycled as it is. ). Even if some pre-incinerated or dismantled display panels are mixed, the progress of the pulverization hardly changes, so that the method of the present invention has a wide processing raw material range.
(4) Indium can be recovered at a high recovery rate by acid treatment, solvent extraction, and electrolytic treatment. In addition, since a reducing agent such as zinc is not used for recovering indium, the raw material cost is low (claim 4).
Hereinafter, the present invention will be described in more detail by way of examples in which a panel of a liquid crystal display device is processed, but it will be understood that other panels including glass and transparent electrodes can be processed in the same manner.
インジウム濃度120g/ton である液晶パネル30tonを図2に示す工程により処理した。
ガラス粉砕機としては株式会社環境保全サービスの無機物万能破砕機クリスター(商品名)を使用した。この主な使用は次のとおりである。
1回当たり処理量:5〜10kg
処理時間:5〜45秒
モーター:1.5kW
回転刃:ステンレスブレード50〜60枚、回転数400〜500rpm
A liquid crystal panel 30 ton having an indium concentration of 120 g / ton was processed by the process shown in FIG.
As the glass crusher, an inorganic all-purpose crusher (trade name) from Environmental Conservation Service Co., Ltd. was used. The main uses are as follows.
Processing amount per time: 5-10kg
Processing time: 5-45 seconds
Motor: 1.5kW
Rotating blade: 50-60 stainless steel blades, 400-500 rpm
粉砕物の分級は250μmの篩目を有する振動篩を使用して行い分級し、250μm以下のガラス粉を回収した。この結果、インジウム濃度が1000g/tonのインジウム濃縮ガラス微粉が3ton、250μmより粗いガラス粗粒が27ton生産された。それぞれの割合(質量%)、インジウム濃度(g/ton)と分配率(%)を表1に示す。
The pulverized product was classified using a vibrating sieve having a 250 μm mesh, and glass powder of 250 μm or less was collected. As a result, 3 tons of indium-concentrated glass fine powder having an indium concentration of 1000 g / ton was produced, and 27 tons of glass coarse particles coarser than 250 μm were produced. Each ratio (mass%), indium concentration (g / ton) and distribution rate (%) are shown in Table 1.
酸溶液としては、塩酸水溶液(塩酸:水容量比=0.5〜2:1)または硫酸水溶液(硫酸:水容量比=0.5〜2:1)を使用して、ガラス微粉の添加割合が約20〜30%となるように設定し、120分間攪拌を行った。
インジウムの溶媒抽出を大八化学株式会社製PC-88Aを用いて行った。この抽出剤は2−エチルヘキシル2−エチルヘキシルホスホネート系であり、その情報はhttp://www/daihachi-chem.co.jp/sehin/pdf/kinz.pdfにて入手できる。溶媒抽出後、塩酸により逆洗を行った。得られた溶液はインジウム濃度が50〜60mg/L、温度30〜40℃、pH2.0〜2.2であった。この溶液から電流密度75〜90A/dm2で電解採取を行い、1ヶ月で3kgの金属インジウムを回収した。
As the acid solution, a hydrochloric acid aqueous solution (hydrochloric acid: water volume ratio = 0.5 to 2: 1) or a sulfuric acid aqueous solution (sulfuric acid: water volume ratio = 0.5 to 2: 1) is used, and the addition ratio of the glass fine powder is about 20 to The mixture was set to 30% and stirred for 120 minutes.
Solvent extraction of indium was performed using PC-88A manufactured by Daihachi Chemical Co., Ltd. This extractant is 2-ethylhexyl 2-ethylhexyl phosphonate, and its information is available at http: //www/daihachi-chem.co.jp/sehin/pdf/kinz.pdf. After solvent extraction, backwashing was performed with hydrochloric acid. The resulting solution had an indium concentration of 50-60 mg / L, a temperature of 30-40 ° C., and a pH of 2.0-2.2. Electrolysis was collected from this solution at a current density of 75 to 90 A / dm 2 , and 3 kg of metal indium was recovered in one month.
本発明法は、コストが低い、再生物のリサイクル価値が高い点で非常に優れたディスプレーパネルのリサイクル法である。 The method of the present invention is a display panel recycling method that is very excellent in terms of low cost and high recycling value of recycled materials.
1−ITO透明電極
2−薄膜トランジスタ
3−ガラス
4−液晶
10−インジウム濃縮微粉
12−ガラス粗粒
1-ITO transparent electrode 2-thin film transistor 3-glass 4-liquid crystal 10-indium concentrated fine powder 12-glass coarse particle
Claims (4)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007086956A JP5065732B2 (en) | 2007-03-29 | 2007-03-29 | Method for recovering indium from display panel |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007086956A JP5065732B2 (en) | 2007-03-29 | 2007-03-29 | Method for recovering indium from display panel |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2008240139A JP2008240139A (en) | 2008-10-09 |
JP5065732B2 true JP5065732B2 (en) | 2012-11-07 |
Family
ID=39911818
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2007086956A Expired - Fee Related JP5065732B2 (en) | 2007-03-29 | 2007-03-29 | Method for recovering indium from display panel |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP5065732B2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5325443B2 (en) * | 2008-03-31 | 2013-10-23 | Dowaエコシステム株式会社 | Method of leaching metal from LCD panel |
JP2012239974A (en) * | 2011-05-19 | 2012-12-10 | Sharp Corp | Method for recycling glass formed with film |
CA2844047A1 (en) * | 2011-08-17 | 2013-02-21 | Jernkontoret | Recovery of lead and indium from glass, primarily from electronic waste material |
ITRM20130324A1 (en) * | 2013-06-04 | 2014-12-05 | Eco Recycling S R L | PROCESS AND PLANT FOR GLASS, PLASTIC AND INDIO RECOVERY FROM LCD PANELS |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3506217B2 (en) * | 1998-09-16 | 2004-03-15 | シャープ株式会社 | LCD panel disposal |
JP2000144748A (en) * | 1998-11-11 | 2000-05-26 | Kajima Corp | Execution method of lightweight mixed soil utilizing glass waste material |
JP2001296508A (en) * | 2000-04-13 | 2001-10-26 | Sharp Corp | Method for processing waste liquid crystal panel |
JP4356519B2 (en) * | 2004-05-31 | 2009-11-04 | 日立造船株式会社 | Method for recycling valuable metals |
JP2006075741A (en) * | 2004-09-10 | 2006-03-23 | Mitsubishi Materials Corp | Method of recycling waste and its recycling apparatus |
JP5071700B2 (en) * | 2005-01-31 | 2012-11-14 | Dowaメタルマイン株式会社 | Indium recovery method |
JP2007270311A (en) * | 2006-03-31 | 2007-10-18 | Aquatech:Kk | Method for recovering indium and indium elution device |
JP5002615B2 (en) * | 2009-05-11 | 2012-08-15 | 日立造船株式会社 | Method for recycling valuable metals |
-
2007
- 2007-03-29 JP JP2007086956A patent/JP5065732B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JP2008240139A (en) | 2008-10-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Silveira et al. | Recovery of indium from LCD screens of discarded cell phones | |
Lee et al. | Recovery of indium from used LCD panel by a time efficient and environmentally sound method assisted HEBM | |
Ferella et al. | Separation and recovery of glass, plastic and indium from spent LCD panels | |
JP5071700B2 (en) | Indium recovery method | |
Fontana et al. | Recent developments on recycling end-of-life flat panel displays: A comprehensive review focused on indium | |
JP5065732B2 (en) | Method for recovering indium from display panel | |
Qin et al. | Leaching of indium and tin from waste LCD by a time-efficient method assisted planetary high energy ball milling | |
Götze et al. | Challenges for the recovery of critical metals from waste electronic equipment-A case study of indium in LCD panels | |
CN103157646A (en) | Comprehensive treatment method for waste liquid crystal display | |
KR20110055385A (en) | Process for leaching from laterite using impact-grinding effect | |
Savvilotidou et al. | Evaluation and comparison of pre-treatment techniques for recovering indium from discarded liquid crystal displays | |
JP4918839B2 (en) | Disposal of display panel waste | |
JP2003247089A (en) | Method of recovering indium | |
JP2003027153A (en) | Method of recovering heavy metal from flying ash | |
KR101528598B1 (en) | A selectively recovery method for indium & gallium from the mixed indium, gallium and znic scraps | |
JP2009155717A (en) | Method for recovering indium | |
JP2011235252A (en) | Method of recycling glass substrate | |
Rocchetti et al. | Innovative method to extract indium from LCD panels | |
CN106467937B (en) | A kind of method of recovery indium and tin | |
CN112708781B (en) | Method for recovering metal Sn from waste circuit board by adopting efficient Sn-removing medicament | |
JP2008073619A (en) | Method of treating liquid crystal panel | |
JP2011052261A (en) | Electrolytic pulverization method of scrap containing conductive metal oxide | |
JP5339762B2 (en) | Method for producing indium metal | |
CN113999969A (en) | Separation method of waste liquid crystal screen indium leaching solution | |
CN110983031A (en) | Comprehensive separation and recovery method for electronic waste |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090910 |
|
A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A712 Effective date: 20101004 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20101006 |
|
RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20101102 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20120424 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20120515 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20120711 |
|
TRDD | Decision of grant or rejection written | ||
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20120807 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20120810 |
|
R150 | Certificate of patent or registration of utility model |
Ref document number: 5065732 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150817 Year of fee payment: 3 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
LAPS | Cancellation because of no payment of annual fees |