JP2016054948A - Method of treating hexavalent chromium-containing substance - Google Patents
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本発明は、６価クロム含有物質を無害化する方法であり、特に６価クロム含有スラグやコンクリート廃材などの６価クロムを含有する塊状の物質から、６価クロムの溶出を防止することが可能な、６価クロム含有物質の処理方法に関する。 The present invention is a method for detoxifying hexavalent chromium-containing substances, and in particular, elution of hexavalent chromium can be prevented from massive substances containing hexavalent chromium such as hexavalent chromium-containing slag and concrete waste. The present invention also relates to a method for treating a hexavalent chromium-containing substance.
フェロクロム、ステンレス鋼、クロム含有合金鋼等、クロムを含有する合金を製造する際に多量に生成するスラグはクロム酸化物を含んでおり、その一部が６価クロムとなり溶出することがある。また、中性化したコンクリート廃材、或いは破砕したコンクリートを含む廃材等からは６価クロムが溶出することが、報告されている。 Slag produced in large quantities when producing an alloy containing chromium, such as ferrochrome, stainless steel, and chromium-containing alloy steel, contains chromium oxide, and some of it may become hexavalent chromium and be eluted. In addition, it has been reported that hexavalent chromium is eluted from neutralized concrete waste materials or waste materials containing crushed concrete.
これらのスラグやコンクリートを路盤材、土木材、埋戻し材等に使用する場合には、スラグやコンクリートからの６価クロムの溶出量を、環境庁告示４６号「土壌の汚染に係わる環境基準について」に定める基準値（０．０５ｍｇ／ｌ）以下に抑制する必要がある。 When these slags and concrete are used for roadbed materials, earthen timber, backfill materials, etc., the amount of hexavalent chromium leaching from the slags and concretes is determined by the Environment Agency Notification No. 46 “Environmental Standards Concerning Soil Contamination”. The reference value (0.05 mg / l) or less defined in “
この基準値を達成するために、様々な処理方法が実施されている。その一つは、クロム酸化物含有物質に硫黄や酸化数が＋５価以下の硫黄を含む水溶液を接触させて、６価クロムを還元する方法である（特許文献１）。クロム酸化物含有物質と水溶液の接触は、水溶液にクロム酸化物含有物質を浸漬する方法や、クロム酸化物含有物質に水溶液を散布する方法等によって行われる。この方法は簡単に処理できるという利点がある。 Various processing methods have been implemented to achieve this reference value. One of them is a method of reducing hexavalent chromium by bringing a chromium oxide-containing substance into contact with an aqueous solution containing sulfur or sulfur having an oxidation number of +5 or less (Patent Document 1). The contact between the chromium oxide-containing substance and the aqueous solution is performed by a method of immersing the chromium oxide-containing substance in the aqueous solution, a method of spraying the aqueous solution on the chromium oxide-containing substance, or the like. This method has the advantage of being easy to handle.
また、溶融状態にあるステンレススラグに改質剤を混合させて、６価クロムの生成を防止する方法がある。改質剤として金属の硫酸塩やＦｅＯ系物質（特許文献２）、あるいはアルミ灰とマグネシア系物質(特許文献３)などが用いられる。 There is also a method of preventing the production of hexavalent chromium by mixing a modifier with stainless steel slag in a molten state. As the modifier, metal sulfate, FeO-based material (Patent Document 2), aluminum ash and magnesia-based material (Patent Document 3) or the like is used.
また、６価クロムを含有する物質に、還元剤として石炭またはコークスを加え、ロータリーキルンで加熱して６価クロムを還元する方法がある（特許文献４）。この方法では、６価クロム含有物質と還元剤を混合し、平均粒径が１５μｍ以下になるように粉砕し、得られた粉砕物に水を加えて成形し、次いで焼成することで、人工骨材を得ている。 Further, there is a method in which coal or coke is added as a reducing agent to a substance containing hexavalent chromium and heated in a rotary kiln to reduce hexavalent chromium (Patent Document 4). In this method, a hexavalent chromium-containing substance and a reducing agent are mixed, pulverized so that the average particle size is 15 μm or less, water is added to the obtained pulverized product, and then fired to obtain an artificial bone. I have the material.
しかしながら、クロム酸化物含有物質に硫黄や酸化数が＋５価以下の硫黄を含む水溶液を接触させる方法では、溶出した６価クロムやクロム酸化物含有物質の表面だけを還元しているので、時間の経過とともにクロム酸化物含有物質の内部に残留した６価クロムが再溶出する可能性がある。また、クロム酸化物含有物質にひびが入ったり、割れたりした場合は、６価クロムが溶出する。溶融状態のスラグを改質する方法では、改質剤の添加によりスラグ容積が増大するという問題が生じる。また、既に冷却固化したスラグを処理するには、スラグを高温に加熱し再溶融する必要があり、コストが高くなってしまう。還元剤として石炭やコークスを使用する方法では、還元効果を高めるために、６価クロム含有物質と還元剤を粉砕する必要がある。さらに、人工骨材として利用するためには、ペレット状に成形する必要があり、コストが高くなるという問題が生じる。 However, in the method of contacting the chromium oxide-containing material with an aqueous solution containing sulfur or sulfur having an oxidation number of +5 or less, only the surface of the eluted hexavalent chromium or chromium oxide-containing material is reduced. With the passage of time, hexavalent chromium remaining inside the chromium oxide-containing material may be re-eluted. Further, when the chromium oxide-containing material is cracked or cracked, hexavalent chromium is eluted. In the method of modifying the molten slag, there is a problem that the volume of the slag increases due to the addition of the modifier. Moreover, in order to process the slag which has already been cooled and solidified, it is necessary to re-melt the slag by heating it to a high temperature, which increases the cost. In the method using coal or coke as the reducing agent, it is necessary to grind the hexavalent chromium-containing substance and the reducing agent in order to enhance the reduction effect. Furthermore, in order to use it as an artificial aggregate, it is necessary to form it into a pellet form, resulting in a problem of increased cost.
本発明は塊状の６価クロム含有物質を低コストで処理する方法であり、長期間にわたって６価クロムの溶出を抑制することが可能な、６価クロム含有物質の処理方法を提供することを目的とする。 The present invention is a method for treating a massive hexavalent chromium-containing substance at a low cost, and an object of the present invention is to provide a method for treating a hexavalent chromium-containing substance capable of suppressing elution of hexavalent chromium over a long period of time. And
本発明によれば、下記（１）〜（１１）に係る発明が提供される。
（１）６価クロム含有物質と還元剤とを加熱処理する６価クロム含有物質の処理方法であって、還元剤が３０〜９８．５重量％の炭素と１．５〜１０重量％の硫黄を含むことを特徴とする６価クロム含有物質の処理方法。
（２）前記還元剤は、炭素と硫黄を含有する物質であることを特徴とする、（１）に記載の６価クロム含有物質の処理方法。
（３）前記炭素と硫黄を含有する物質は、石炭、褐炭、亜炭、泥炭、石油コークス、石油コークス燃焼灰、ゴム、硫黄含有プラスティックの中から選ばれた１つ以上であることを特徴とする、（２）に記載の６価クロム含有物質の処理方法。
（４）前記還元剤は、炭素を含有する物質と硫黄を含有する物質との混合物であることを特徴とする、（１）に記載の６価クロム含有物質の処理方法。
（５）前記炭素を含有する物質は、石炭、褐炭、亜炭、泥炭、石油コークス、石油コークス燃焼灰、ゴム、プラスティック、紙、ペーパースラッジ、木材の中から選ばれた１つ以上であることを特徴とする、（４）に記載の６価クロム含有物質の処理方法。
（６）前記硫黄を含有する物質は、自然硫黄、硫酸塩、石膏の中から選ばれた１つ以上であることを特徴とする、（４）に記載の６価クロム含有物質の処理方法。
（７）加熱処理する温度が１０００℃以上、６価クロム含有物質の融点未満であることを特徴とする、（１）〜（６）のいずれかに記載の６価クロム含有物質の処理方法。
（８）加熱処理する時間が３０分以上、２時間以下であることを特徴とする、（１）〜（７）のいずれかに記載の６価クロム含有物質の処理方法。
（９）前記６価クロム含有物質の粒径が５０ｍｍ以下であることを特徴とする、（１）〜（８）のいずれかに記載の６価クロム含有物質の処理方法。
（１０）前記還元剤の粒径が５ｍｍ以下であることを特徴とする、（１）〜（９）のいずれかに記載の６価クロム含有物質の処理方法。
（１１）（還元剤の重量）／（６価クロム含有物質の重量）の値が０．５〜２の範囲であることを特徴とする、（１）〜（１０）のいずれかに記載の６価クロム含有物質の処理方法。
According to the present invention, the inventions according to the following (1) to (11) are provided.
(1) A method for treating a hexavalent chromium-containing substance by heat-treating a hexavalent chromium-containing substance and a reducing agent, wherein the reducing agent is 30 to 98.5% by weight of carbon and 1.5 to 10% by weight of sulfur. A method for treating a hexavalent chromium-containing substance, comprising:
(2) The method for treating a hexavalent chromium-containing material according to (1), wherein the reducing agent is a material containing carbon and sulfur.
(3) The substance containing carbon and sulfur is one or more selected from coal, lignite, lignite, peat, petroleum coke, petroleum coke combustion ash, rubber, and sulfur-containing plastic. The processing method of the hexavalent chromium containing substance as described in (2).
(4) The method for treating a hexavalent chromium-containing substance according to (1), wherein the reducing agent is a mixture of a substance containing carbon and a substance containing sulfur.
(5) The carbon-containing substance is at least one selected from coal, lignite, lignite, peat, petroleum coke, petroleum coke combustion ash, rubber, plastic, paper, paper sludge, and wood. The method for treating a hexavalent chromium-containing substance according to (4), which is characterized in that
(6) The method for treating a hexavalent chromium-containing substance according to (4), wherein the sulfur-containing substance is one or more selected from natural sulfur, sulfate, and gypsum.
(7) The method for treating a hexavalent chromium-containing material according to any one of (1) to (6), wherein the heat treatment temperature is 1000 ° C. or higher and lower than the melting point of the hexavalent chromium-containing material.
(8) The method for treating a hexavalent chromium-containing substance according to any one of (1) to (7), wherein the heat treatment time is 30 minutes or more and 2 hours or less.
(9) The method for treating a hexavalent chromium-containing material according to any one of (1) to (8), wherein a particle size of the hexavalent chromium-containing material is 50 mm or less.
(10) The method for treating a hexavalent chromium-containing substance according to any one of (1) to (9), wherein a particle diameter of the reducing agent is 5 mm or less.
(11) A value of (weight of reducing agent) / (weight of hexavalent chromium-containing substance) is in a range of 0.5 to 2, according to any one of (1) to (10) A method for treating hexavalent chromium-containing material.
本発明によれば、６価クロム含有物質から６価クロムが溶出するのを、長期間にわたって抑制することが可能となる。また、塊状の６価クロム含有物質を低コストで処理することができる。 According to the present invention, it is possible to suppress elution of hexavalent chromium from a hexavalent chromium-containing substance over a long period of time. In addition, massive hexavalent chromium-containing materials can be processed at low cost.
以下、本発明の実施の形態について詳細に説明する。
本発明の実施形態は、６価クロム含有物質と還元剤とを混合して加熱処理する方法であって、還元剤が３０〜９８．５重量％の炭素と１．５〜１０重量％の硫黄を含むことを特徴とする。従来、６価クロムの還元剤として、炭素や硫黄が単独に使われてきた。しかし、炭素と硫黄の双方を含んだ還元剤を用いて６価クロム含有物質を加熱処理することにより、６価クロム含有物質から６価クロムが溶出するのを抑制する効果は相乗効果的に高まる。
Hereinafter, embodiments of the present invention will be described in detail.
An embodiment of the present invention is a method in which a hexavalent chromium-containing substance and a reducing agent are mixed and heat-treated, wherein the reducing agent is 30 to 98.5% by weight of carbon and 1.5 to 10% by weight of sulfur. It is characterized by including. Conventionally, carbon or sulfur has been used alone as a reducing agent for hexavalent chromium. However, the effect of suppressing the elution of hexavalent chromium from the hexavalent chromium-containing material is synergistically increased by heat-treating the hexavalent chromium-containing material using a reducing agent containing both carbon and sulfur. .
還元剤中の炭素の含有量は、３０〜９８．５重量％の範囲であることが好ましい。炭素の含有量が高い方が、還元剤の使用量を少なくすることができるのでより好ましい。より好ましい炭素の含有量は、５０重量％以上であり、さらに好ましくは７０重量％以上である。還元剤中の硫黄の含有量は、１．５〜１０重量％の範囲であることが好ましい。硫黄の含有量が１．５重量％よりも低い場合は、還元効果が不十分となり、処理したスラグを長期間保管している間に６価クロムの溶出が生じる虞がある。硫黄の含有量が高い方が、還元効果が高くなるのでより好ましい。より好ましい硫黄の含有量は３重量％以上である。硫黄の含有量が１０重量％よりも高い場合は、亜硫酸ガスの発生量が多くなるので好ましくない。還元剤が６０〜９７重量％の炭素と３〜１０重量％の硫黄を含むことがより好ましい。 The carbon content in the reducing agent is preferably in the range of 30 to 98.5% by weight. A higher carbon content is more preferable because the amount of reducing agent used can be reduced. The carbon content is more preferably 50% by weight or more, and still more preferably 70% by weight or more. The sulfur content in the reducing agent is preferably in the range of 1.5 to 10% by weight. When the sulfur content is lower than 1.5% by weight, the reduction effect is insufficient, and hexavalent chromium may be eluted while the treated slag is stored for a long time. A higher sulfur content is more preferable because the reduction effect is higher. A more preferable sulfur content is 3% by weight or more. If the sulfur content is higher than 10% by weight, the amount of sulfurous acid gas generated is increased, which is not preferable. More preferably, the reducing agent comprises 60-97 wt% carbon and 3-10 wt% sulfur.
還元剤は、炭素と硫黄の両方を含む物質であってもよいし、炭素を含む物質と硫黄を含む物質の混合物であってもよい。ここでいう混合物とは、炭素を含む物質と硫黄を含む物質とが均一に混ざり合ったものである必要はなく、炭素を含む物質と硫黄を含む物質を合わせたものでもよい。 The reducing agent may be a substance containing both carbon and sulfur, or may be a mixture of a substance containing carbon and a substance containing sulfur. The mixture here does not need to be a material in which a substance containing carbon and a substance containing sulfur are uniformly mixed, and may be a combination of a substance containing carbon and a substance containing sulfur.
炭素と硫黄の両方を含む物質としては、石炭、褐炭、亜炭、泥炭、石油コークス、石油コークス燃焼灰、ゴム、硫黄含有プラスティック等が挙げられる。これらの物質中には、１．５〜１０重量％の硫黄が含まれていることが必要である。硫黄含有プラスティックとしては、チオール樹脂、スルホシキド樹脂、スルホン樹脂等がある。 Examples of the substance containing both carbon and sulfur include coal, lignite, lignite, peat, petroleum coke, petroleum coke combustion ash, rubber, and sulfur-containing plastic. It is necessary that these substances contain 1.5 to 10% by weight of sulfur. Examples of the sulfur-containing plastic include a thiol resin, a sulfoxide resin, and a sulfone resin.
炭素を含有する物質としては、石炭、褐炭、亜炭、泥炭、石油コークス、石油コークス燃焼灰、ゴム、プラスティック、紙、ペーパースラッジ、木材等が挙げられる。これらの物質中には硫黄が含まれていても構わないし、含まれていなくても構わない。硫黄を含有する物質と合わせて、還元剤中の硫黄の含有量が１．５〜１０重量％となるように調整すればよい。石炭の炭素含有量は８０％以上で、泥炭の炭素含有量は７０％程度である。また、木材の炭素含有量はおよそ５０％である。 Examples of the carbon-containing substance include coal, lignite, lignite, peat, petroleum coke, petroleum coke combustion ash, rubber, plastic, paper, paper sludge, and wood. These substances may or may not contain sulfur. What is necessary is just to adjust so that content of sulfur in a reducing agent may become 1.5 to 10 weight% in combination with the substance containing sulfur. The carbon content of coal is 80% or more, and the carbon content of peat is about 70%. The carbon content of the wood is approximately 50%.
硫黄を含有する物質としては、自然硫黄、硫酸塩、石膏等が挙げられる。石膏は石膏ボードでもよいし、紙が付いた石膏ボード廃材でもよい。また、ＳＯｘを含有する排ガスを水酸化カルシウムで吸収除害する際に生成する石膏（硫酸カルシウム）を使用することができる。硫酸塩や石膏等の硫黄酸化物から構成された物質を還元剤として用いる場合、硫黄酸化物は加熱処理中に炭素により還元されて、６価クロムを還元する作用を呈する。 Examples of the substance containing sulfur include natural sulfur, sulfate, gypsum and the like. The gypsum may be a gypsum board or a waste gypsum board with paper. Moreover, gypsum (calcium sulfate) produced when absorbing and detoxifying exhaust gas containing SOx with calcium hydroxide can be used. When a substance composed of sulfur oxides such as sulfates and gypsum is used as a reducing agent, the sulfur oxides are reduced by carbon during the heat treatment and exhibit the action of reducing hexavalent chromium.
加熱処理する温度は、１０００℃以上で６価クロム含有物質の融点未満であることが好ましい。加熱処理する温度が１０００℃未満の場合は、還元効果が不十分となり、処理されたスラグを長期間保管している間に６価クロムの溶出が生じる虞がある。更に長期間にわたって、６価クロムの溶出量を環境基準以下に抑制するためには、加熱処理する温度は１１００℃以上であることが好ましい。また、加熱処理する温度が１５００℃を超えると、６価クロム含有物質や還元剤が融着し始めるので、１５００℃以下であることが好ましい。エネルギーコストの面からも、加熱処理する温度は１５００℃以下であることが好ましい。 The temperature for the heat treatment is preferably 1000 ° C. or higher and lower than the melting point of the hexavalent chromium-containing substance. When the temperature for the heat treatment is less than 1000 ° C., the reduction effect is insufficient, and hexavalent chromium may be eluted while the treated slag is stored for a long time. Further, in order to suppress the elution amount of hexavalent chromium below the environmental standard over a long period of time, the temperature for the heat treatment is preferably 1100 ° C. or higher. Moreover, since the hexavalent chromium containing material and the reducing agent start to be fused when the temperature for heat treatment exceeds 1500 ° C., the temperature is preferably 1500 ° C. or lower. Also from the viewpoint of energy cost, the temperature for the heat treatment is preferably 1500 ° C. or less.
加熱処理する時間は、加熱処理温度や６価クロム含有物質の大きさに依存するが、３０分〜２時間であることが好ましい。加熱処理する時間が３０分未満の場合は、還元効果が不十分となり、処理されたスラグを長期間保管している間に６価クロムの溶出が生じる虞がある。また、エネルギーコストの面から、加熱処理する時間は２時間以下であることが好ましい。 The heat treatment time depends on the heat treatment temperature and the size of the hexavalent chromium-containing substance, but is preferably 30 minutes to 2 hours. When the heat treatment time is less than 30 minutes, the reduction effect is insufficient, and hexavalent chromium may be eluted while the treated slag is stored for a long time. Moreover, it is preferable that the heat processing time is 2 hours or less from the viewpoint of energy cost.
加熱処理の方法は特に問わず、処理する６価クロム含有物質の量、形状等を踏まえ適切な加熱炉を選定すれば良い。また、連続的に処理しても良いし、バッチ式に処理しても
良い。加熱方法についても、バーナーによる内燃焼式、ヒーターによる電気加熱等が利用できるが、ロータリーキルン等の内燃焼式の方がコスト的に優れている。
The heating method is not particularly limited, and an appropriate heating furnace may be selected based on the amount, shape, etc. of the hexavalent chromium-containing material to be processed. Moreover, you may process continuously and may process in a batch type. Regarding the heating method, an internal combustion type using a burner, electric heating using a heater, or the like can be used, but an internal combustion type such as a rotary kiln is superior in cost.
６価クロム含有物質の粒径は５０ｍｍ以下であることが好ましい。これは、最も大きい粒子が直径５０ｍｍということで、全ての６価クロム含有物質が５０ｍｍのサイズの網目を通るということである。６価クロム含有物質の粒径が５０ｍｍを超えると、６価クロム含有物質の内部まで還元できずに、長期間保管している間に６価クロムの溶出が生じる虞がある。６価クロム含有物質の粒径は３０ｍｍ以下であることがより好ましい。６価クロム含有物質の粒径は小さくても処理は可能であるが、取扱いの容易さの点から１ｍｍ以上であることが好ましい。 The particle size of the hexavalent chromium-containing material is preferably 50 mm or less. This means that the largest particles have a diameter of 50 mm, and all hexavalent chromium-containing materials pass through a 50 mm size mesh. If the particle size of the hexavalent chromium-containing material exceeds 50 mm, the hexavalent chromium-containing material cannot be reduced to the inside, and hexavalent chromium may be eluted during long-term storage. The particle size of the hexavalent chromium-containing substance is more preferably 30 mm or less. The hexavalent chromium-containing substance can be processed even if the particle size is small, but it is preferably 1 mm or more from the viewpoint of ease of handling.
還元剤の粒径は５ｍｍ以下であることが好ましい。還元剤の粒径が５ｍｍより大きい場合、６価クロム含有物質の露出面積が大きくなり、還元効果が不十分になる可能性がある。還元剤の粒径は小さくても処理は可能であるが、取扱いの容易さの点から０．５ｍｍ以上であることが好ましい。 The particle size of the reducing agent is preferably 5 mm or less. When the particle size of the reducing agent is larger than 5 mm, the exposed area of the hexavalent chromium-containing substance is increased, and the reduction effect may be insufficient. Although the treatment is possible even if the particle size of the reducing agent is small, it is preferably 0.5 mm or more from the viewpoint of ease of handling.
６価クロム含有物質と還元剤との比率は、還元剤に含有される炭素や硫黄の量に影響されるが、（還元剤の重量）／（６価クロム含有物質の重量）の値が０．５〜２の範囲であることが好ましい。上記値が０．５より小さいと、加熱処理中に６価クロム含有物質と還元剤が接触する面積が小さくなり、還元効果が不十分になる可能性が有る。また、還元された３価クロムが再酸化されて６価クロムになる虞がある。上記値が２よりも大きい場合は、６価クロム含有物質の処理量が少なくなり、効率が悪くなる。 The ratio between the hexavalent chromium-containing substance and the reducing agent is influenced by the amount of carbon and sulfur contained in the reducing agent, but the value of (weight of reducing agent) / (weight of hexavalent chromium-containing substance) is 0. Preferably it is in the range of 5-2. If the above value is smaller than 0.5, the area where the hexavalent chromium-containing substance and the reducing agent come into contact with each other during the heat treatment becomes small, and the reduction effect may be insufficient. Further, the reduced trivalent chromium may be reoxidized to hexavalent chromium. When the said value is larger than 2, the processing amount of a hexavalent chromium containing material will decrease and efficiency will worsen.
加熱処理後の冷却時にも注意が必要である。加熱処理において還元剤の炭素と硫黄が完全に消費されてしまうと、冷却中に３価クロムが再び酸化されて６価クロムになる。そのため、加熱処理が終了した時点で、還元剤中の炭素または硫黄が残留する様に、６価クロム含有物質と還元剤との比率を調整することが好ましい。あるいは、加熱処理後は不活性ガス雰囲気中で冷却するか、水等によって急冷してもよい。 Care must also be taken when cooling after heat treatment. When the reducing agent carbon and sulfur are completely consumed in the heat treatment, the trivalent chromium is oxidized again during the cooling to become hexavalent chromium. Therefore, it is preferable to adjust the ratio of the hexavalent chromium-containing substance and the reducing agent so that carbon or sulfur in the reducing agent remains when the heat treatment is completed. Alternatively, after the heat treatment, it may be cooled in an inert gas atmosphere or quenched with water or the like.
加熱処理されたスラグと還元剤は分離されて、還元剤は炭素含有量と硫黄含有量を調整された後、再利用される。スラグと還元剤の分離には、スクリーン法や比重分離法等が利用できる。 The heat-treated slag and the reducing agent are separated, and the reducing agent is reused after adjusting the carbon content and the sulfur content. A screen method, a specific gravity separation method, or the like can be used to separate the slag and the reducing agent.
以下、本発明を実施例に基づいて具体的に説明する。しかし、本発明は実施例に限定されるものではない。 Hereinafter, the present invention will be specifically described based on examples. However, the present invention is not limited to the examples.
（実施例１）
６価クロムを含有するスラグを破砕し、スクリーニングにより粒径１０〜３０ｍｍのスラグを選別した。次に還元剤として、粒径４ｍｍ以下、炭素含有量が７４．５重量％で、硫黄含有量が７．８重量％である石油コークスを準備した。スラグ５０ｇと石油コークス５０ｇを混合し、混合物をアルミナ坩堝に充填し、アルミナ坩堝を電気炉内にセットした。次に電気炉内に１００ｍｌ／分の窒素ガスを流しながら昇温し、炉内の温度が１１００℃に到達してから炉内の温度を４時間保持した後、室温まで冷却した。冷却後、スラグと還元剤を分離し、スラグを水洗した後、粒径２ｍｍ以下に粉砕した。粉砕したスラグから、環境庁告示４６号溶出試験の方法により６価クロムを溶出させて、検液を作製した。環境庁告示４６号溶出試験では溶出時間は６時間であるが、長期間の溶出量を評価するため、溶出時間を６時間（０．２５日）、５日、１０日、２０日、３０日、５０日、１００日とした検液を作製した。検液中の６価クロム濃度の分析には、ジフェニルカルバジド発色法を用いた。以上の様にして分析した６価クロムの溶出量を表１と図１に示す。溶出量は、検液１リットル中の６価クロムのｍｇ量で表され、環境基準値は０．０５ｍｇ／ｌ以下である。
(Example 1)
Slag containing hexavalent chromium was crushed, and slag having a particle size of 10 to 30 mm was selected by screening. Next, petroleum coke having a particle size of 4 mm or less, a carbon content of 74.5% by weight, and a sulfur content of 7.8% by weight was prepared as a reducing agent. 50 g of slag and 50 g of petroleum coke were mixed, the mixture was filled in an alumina crucible, and the alumina crucible was set in an electric furnace. Next, the temperature was raised while flowing 100 ml / min of nitrogen gas into the electric furnace, and after the temperature in the furnace reached 1100 ° C., the temperature in the furnace was maintained for 4 hours, and then cooled to room temperature. After cooling, the slag and the reducing agent were separated, and the slag was washed with water and then pulverized to a particle size of 2 mm or less. Hexavalent chromium was eluted from the pulverized slag by the method of dissolution test No. 46 of the Environment Agency to prepare a test solution. Although the dissolution time is 6 hours in the Environmental Agency Notification No. 46 dissolution test, the dissolution time is 6 hours (0.25 days), 5 days, 10 days, 20 days, and 30 days in order to evaluate the long-term dissolution amount. Samples were prepared for 50 days and 100 days. A diphenylcarbazide coloring method was used for analysis of hexavalent chromium concentration in the test solution. The elution amount of hexavalent chromium analyzed as described above is shown in Table 1 and FIG. The elution amount is expressed in mg of hexavalent chromium in 1 liter of the test solution, and the environmental standard value is 0.05 mg / l or less.
（比較例１）
還元剤として、炭素含有量が９９．５重量％で硫黄含有量が０．１重量％未満である高純度炭素を用いた以外は、実施例１と同一の条件で６価クロムの溶出量の分析を行った。
(Comparative Example 1)
As the reducing agent, the amount of elution of hexavalent chromium was the same as in Example 1 except that high-purity carbon having a carbon content of 99.5% by weight and a sulfur content of less than 0.1% by weight was used. Analysis was carried out.
（比較例２）
固体の還元剤を使用せず、電気炉内に窒素ガスの代わりに１００ｍｌ／分の水素ガスを流すことで、水素ガスによる還元を行った。これ以外の条件は、実施例１と同一の条件で６価クロムの溶出量の分析を行った。
(Comparative Example 2)
Reduction with hydrogen gas was performed by flowing 100 ml / min of hydrogen gas in the electric furnace instead of nitrogen gas without using a solid reducing agent. Except for this, the elution amount of hexavalent chromium was analyzed under the same conditions as in Example 1.
（比較例３）
６価クロムを含有するスラグを電気炉で処理せずに、６価クロムの溶出量の分析を行った。
(Comparative Example 3)
The elution amount of hexavalent chromium was analyzed without treating slag containing hexavalent chromium in an electric furnace.
比較例１〜３の分析結果を、実施例１と共に表１及び図１に示す。
炭素と硫黄を含む還元剤で処理した実施例１は、１００日後でも６価クロムの溶出は認められなかった。炭素のみを含む還元剤で処理した比較例１は、５日までは溶出量は環境基準値（０．０５ｍｇ／ｌ）以下であったが、１０日以降は環境基準値以上になった。水素で還元した比較例２は、１０日までは溶出量は環境基準値以下であったが、２０日以降は環境基準値以上になった。処理をしなかった比較例３は、６時間後で既に溶出量が環境基準値を超え、その後時間の経過と共に溶出量が増加した。
The analysis results of Comparative Examples 1 to 3 are shown in Table 1 and FIG.
In Example 1 treated with a reducing agent containing carbon and sulfur, elution of hexavalent chromium was not observed even after 100 days. In Comparative Example 1 treated with a reducing agent containing only carbon, the elution amount was not more than the environmental standard value (0.05 mg / l) until the 5th day, but became the environmental standard value or more after the 10th day. In Comparative Example 2 reduced with hydrogen, the elution amount was not more than the environmental standard value until the 10th day, but became the environmental standard value or more after the 20th day. In Comparative Example 3 which was not treated, the elution amount already exceeded the environmental standard value after 6 hours, and the elution amount increased with the passage of time thereafter.
（実施例２)
実施例１と同じ６価クロムを含有するスラグを破砕し、スクリーニングにより粒径１０〜３０ｍｍのスラグを選別した。還元剤として、粒径４ｍｍ以下、炭素含有量が８７．５重量％で、硫黄含有量が８．５重量％である石油コークスを準備した。スラグ５００ｇと石油コークス５００ｇを混合し、混合物をアルミナ坩堝に充填した。アルミナ坩堝にアルミナ製の蓋をして電気炉内にセットした。その後、電気炉内の雰囲気を空気にしたままで昇温し、炉内の温度を１０００℃で１時間保持した後、室温まで冷却した。冷却後、スラグと還元剤を分離し、スラグを水洗した後、粒径２ｍｍ以下に粉砕した。実施例１と同一方法で６価クロムの溶出量を分析した。
(Example 2)
The same slag containing hexavalent chromium as in Example 1 was crushed, and slag having a particle size of 10 to 30 mm was selected by screening. As a reducing agent, petroleum coke having a particle size of 4 mm or less, a carbon content of 87.5% by weight, and a sulfur content of 8.5% by weight was prepared. 500 g of slag and 500 g of petroleum coke were mixed, and the mixture was filled in an alumina crucible. The alumina crucible was covered with an alumina lid and set in an electric furnace. Thereafter, the temperature in the electric furnace was raised while keeping the atmosphere in air, and the temperature in the furnace was maintained at 1000 ° C. for 1 hour, and then cooled to room temperature. After cooling, the slag and the reducing agent were separated, and the slag was washed with water and then pulverized to a particle size of 2 mm or less. The elution amount of hexavalent chromium was analyzed by the same method as in Example 1.
（実施例３）
電気炉の温度を１１００℃で１時間保持した以外は、実施例２と同一の条件で６価クロムの溶出量の分析を行った。
(Example 3)
The elution amount of hexavalent chromium was analyzed under the same conditions as in Example 2 except that the temperature of the electric furnace was maintained at 1100 ° C. for 1 hour.
（実施例４）
電気炉の温度を１２５０℃で１時間保持した以外は、実施例２と同一の条件で６価クロムの溶出量の分析を行った。
Example 4
The elution amount of hexavalent chromium was analyzed under the same conditions as in Example 2 except that the temperature of the electric furnace was maintained at 1250 ° C. for 1 hour.
（実施例５）
電気炉の温度を１５００℃で１時間保持した以外は、実施例２と同一の条件で６価クロムの溶出量の分析を行った。
(Example 5)
The elution amount of hexavalent chromium was analyzed under the same conditions as in Example 2 except that the temperature of the electric furnace was maintained at 1500 ° C. for 1 hour.
実施例２〜５の分析結果を表２に示す。還元処理をするために保持した温度（処理温度）が１０００℃である実施例２の場合、１０日までは６価クロムの溶出が認められなかったが、２０日後に６価クロムの溶出が認められた。１００日後には溶出量は０．０４ｍｇ／ｌまで上昇したが、環境基準値以下であった。処理温度を高くするに従って溶出量は減少し、処理温度が１２５０℃以上（実施例４及び５）では、１００日後でも６価クロムの溶出は認められなかった。また、１５００℃で処理したスラグでは、表面の一部に変形が見られた。 The analysis results of Examples 2 to 5 are shown in Table 2. In the case of Example 2 where the temperature maintained for the reduction treatment (treatment temperature) was 1000 ° C., elution of hexavalent chromium was not observed until 10 days, but elution of hexavalent chromium was observed after 20 days. It was. After 100 days, the elution amount increased to 0.04 mg / l, but was below the environmental standard value. As the treatment temperature was increased, the elution amount decreased. When the treatment temperature was 1250 ° C. or higher (Examples 4 and 5), elution of hexavalent chromium was not observed even after 100 days. Moreover, in the slag processed at 1500 degreeC, the deformation | transformation was seen in a part of surface.
（実施例６〜１７）
実施例１と同じ６価クロムを含有するスラグを破砕し、粒径１０〜２０ｍｍと粒径２０〜３０ｍｍの２種類のスラグをスクリーニングした。還元剤として次の２種類を準備した。一つは、粒径４ｍｍ以下、炭素含有量が８７．５重量％で、硫黄含有量が８．４重量％である石油コークスである。もう一つは、粒径１ｍｍ以下、炭素含有量が６３．７重量％で、硫黄含有量が３．１重量％である石油コークス燃焼集塵灰である。表３に示すスラグ粒径、還元剤及び処理温度の組み合わせで還元処理を行った。表３に示す条件以外は、実施例２と同一条件で還元処理を行い、６価クロムの溶出量を分析した。
(Examples 6 to 17)
The same slag containing hexavalent chromium as in Example 1 was crushed, and two types of slag having a particle size of 10 to 20 mm and a particle size of 20 to 30 mm were screened. The following two types were prepared as reducing agents. One is petroleum coke having a particle size of 4 mm or less, a carbon content of 87.5% by weight, and a sulfur content of 8.4% by weight. The other is petroleum coke combustion dust ash having a particle size of 1 mm or less, a carbon content of 63.7% by weight, and a sulfur content of 3.1% by weight. Reduction treatment was performed using a combination of the slag particle size, the reducing agent, and the treatment temperature shown in Table 3. Except for the conditions shown in Table 3, reduction treatment was performed under the same conditions as in Example 2, and the elution amount of hexavalent chromium was analyzed.
分析結果を表３に示す。還元剤として石油コークスを用いた実施例６では、１００日後でも６価クロムの溶出が認められなかったが、還元剤として石油コークス燃焼集塵灰を用いた実施例９では、１００日後に僅かであるが６価クロムの溶出が認められた。硫黄含有量が高い還元剤の方が、６価クロムの溶出を抑制する効果が高いという結果になった。また、実施例１０、１１では、処理温度が実施例９よりも高かったため、１００日後でも６価クロムの溶出は認められなかった。 The analysis results are shown in Table 3. In Example 6 using petroleum coke as the reducing agent, elution of hexavalent chromium was not observed even after 100 days, but in Example 9 using petroleum coke combustion dust ash as the reducing agent, it was slightly after 100 days. Although there was elution of hexavalent chromium. As a result, the reducing agent having a higher sulfur content has a higher effect of suppressing elution of hexavalent chromium. In Examples 10 and 11, the treatment temperature was higher than that in Example 9, and thus no elution of hexavalent chromium was observed even after 100 days.
実施例６と実施例１２との比較、実施例９と実施例１５との比較では、スラグ粒径が小さい方が、６価クロムの溶出を抑制する効果が高いという結果になった。 In the comparison between Example 6 and Example 12 and the comparison between Example 9 and Example 15, the smaller the slag particle size, the higher the effect of suppressing the elution of hexavalent chromium.
（実施例１８〜２１及び比較例４）
実施例１と同じ６価クロムを含有するスラグを破砕し、スクリーニングにより粒径１０〜３０ｍｍのスラグを選別した。還元剤として、粒径１ｍｍ以下、炭素含有量が６３．７重量％で、硫黄含有量が３．１重量％である石油コークス燃焼集塵灰を準備した。表４に示す量のスラグと還元剤（石油コークス燃焼集塵灰）を混合し、混合物をアルミナ坩堝に充填した。アルミナ坩堝にアルミナ製の蓋をして電気炉内にセットした。その後、電気炉内の雰囲気を空気にしたままで昇温し、炉内の温度を１２００℃で１時間保持した後、室温まで冷却した。冷却後、スラグと還元剤を分離し、スラグを水洗した後、粒径２ｍｍ以下に粉砕した。実施例１と同一方法で６価クロムの溶出量を分析した。
(Examples 18 to 21 and Comparative Example 4)
The same slag containing hexavalent chromium as in Example 1 was crushed, and slag having a particle size of 10 to 30 mm was selected by screening. As a reducing agent, petroleum coke combustion dust collection ash having a particle size of 1 mm or less, a carbon content of 63.7% by weight, and a sulfur content of 3.1% by weight was prepared. The amount of slag shown in Table 4 and a reducing agent (petroleum coke combustion dust ash) were mixed, and the mixture was filled in an alumina crucible. The alumina crucible was covered with an alumina lid and set in an electric furnace. Thereafter, the temperature in the electric furnace was increased while keeping the atmosphere in air, and the temperature in the furnace was maintained at 1200 ° C. for 1 hour, and then cooled to room temperature. After cooling, the slag and the reducing agent were separated, and the slag was washed with water and then pulverized to a particle size of 2 mm or less. The elution amount of hexavalent chromium was analyzed by the same method as in Example 1.
分析結果を表４に示す。還元剤／スラグ比が０．４である比較例４では、５０日後に溶出量が環境基準値に達し、その後環境基準値を超えた。還元剤／スラグ比が０．５以上である実施例１８〜２１では、１００後でも溶出量は環境基準値以下であった。 The analysis results are shown in Table 4. In Comparative Example 4 in which the reducing agent / slag ratio was 0.4, the elution amount reached the environmental standard value after 50 days, and then exceeded the environmental standard value. In Examples 18 to 21 in which the reducing agent / slag ratio was 0.5 or more, even after 100, the elution amount was not more than the environmental standard value.
（実施例２２〜２５及び比較例５）
実施例１と同じ６価クロムを含有するスラグを破砕し、スクリーニングにより粒径１０〜３０ｍｍのスラグを選別した。還元剤として、粒径１ｍｍ以下、炭素含有量が６３．７重量％で、硫黄含有量が３．１重量％である石油コークス燃焼集塵灰を準備した。スラグ５００ｇと石油コークス５００ｇを混合し、混合物をアルミナ坩堝に充填した。アルミナ坩堝にアルミナ製の蓋をして電気炉内にセットした。その後、電気炉内の雰囲気を空気にしたままで昇温し、表５に示す処理時間だけ炉内の温度を１２００℃に保持した。冷却後、スラグと還元剤を分離し、スラグを水洗した後、粒径２ｍｍ以下に粉砕した。実施例１と同一方法で６価クロムの溶出量を分析した。
(Examples 22 to 25 and Comparative Example 5)
The same slag containing hexavalent chromium as in Example 1 was crushed, and slag having a particle size of 10 to 30 mm was selected by screening. As a reducing agent, petroleum coke combustion dust collection ash having a particle size of 1 mm or less, a carbon content of 63.7% by weight, and a sulfur content of 3.1% by weight was prepared. 500 g of slag and 500 g of petroleum coke were mixed, and the mixture was filled in an alumina crucible. The alumina crucible was covered with an alumina lid and set in an electric furnace. Thereafter, the temperature in the electric furnace was increased while keeping the atmosphere in air, and the temperature in the furnace was maintained at 1200 ° C. for the treatment time shown in Table 5. After cooling, the slag and the reducing agent were separated, and the slag was washed with water and then pulverized to a particle size of 2 mm or less. The elution amount of hexavalent chromium was analyzed by the same method as in Example 1.
分析結果を表５に示す。処理時間が２０分である比較例５は、１００日後に溶出量が環境基準値に達した。処理時間が３０分以上である実施例２２〜２５は、１００日後でも溶出量は環境基準値以下であった。 The analysis results are shown in Table 5. In Comparative Example 5 in which the treatment time was 20 minutes, the elution amount reached the environmental standard value after 100 days. In Examples 22 to 25 in which the treatment time was 30 minutes or more, the elution amount was not more than the environmental standard value even after 100 days.
（実施例２６〜２９及び比較例６）
実施例１と同じ６価クロムを含有するスラグを破砕し、スクリーニングにより粒径１０〜３０ｍｍのスラグを選別した。還元剤として、粒径５ｍｍ以下、炭素含有量が７２．９重量％で、硫黄含有量が０．５重量％である石炭と、粒径１ｍｍ以下の２水石膏（ＣａＳＯ４・２Ｈ２Ｏ）を準備した。スラグ５００ｇ、石炭５００ｇ及び表６の硫黄添加量になる重量の２水石膏を混合した。硫黄添加量とは、混合した２水石膏中の硫黄の重量である。混合した２水石膏の重量が２６．８ｇであるとき、硫黄添加量は５ｇになる。硫黄含有量は、石炭と２水石膏を合わせた全還元剤中の硫黄の含有量である。混合物をアルミナ坩堝に充填し、アルミナ坩堝にアルミナ製の蓋をして電気炉内にセットした。その後、電気炉内の雰囲気を空気にしたままで昇温し、炉内の温度を１２００℃で１時間保持した後、室温まで冷却した。冷却後、スラグと還元剤を分離し、スラグを水洗した後、粒径２ｍｍ以下に粉砕した。実施例１と同一方法で６価クロムの溶出量を分析した。
(Examples 26 to 29 and Comparative Example 6)
The same slag containing hexavalent chromium as in Example 1 was crushed, and slag having a particle size of 10 to 30 mm was selected by screening. As a reducing agent, coal having a particle size of 5 mm or less, a carbon content of 72.9% by weight, and a sulfur content of 0.5% by weight, and dihydrate gypsum (CaSO 4 .2H 2 O) having a particle size of 1 mm or less. Prepared. 500 g of slag, 500 g of coal, and dihydrate gypsum having a weight corresponding to the sulfur addition amount shown in Table 6 were mixed. The amount of sulfur added is the weight of sulfur in the mixed dihydrate gypsum. When the weight of the mixed dihydrate gypsum is 26.8 g, the sulfur addition amount is 5 g. Sulfur content is the content of sulfur in the total reducing agent that combines coal and dihydrate gypsum. The mixture was filled in an alumina crucible, and the alumina crucible was covered with an alumina lid and set in an electric furnace. Thereafter, the temperature in the electric furnace was increased while keeping the atmosphere in air, and the temperature in the furnace was maintained at 1200 ° C. for 1 hour, and then cooled to room temperature. After cooling, the slag and the reducing agent were separated, and the slag was washed with water and then pulverized to a particle size of 2 mm or less. The elution amount of hexavalent chromium was analyzed by the same method as in Example 1.
分析結果を表６に示す。硫黄含有量が０．５重量％である比較例６では、３０日後には溶出量が環境基準値を超えた。硫黄含有量が１．４重量％である実施例２６では、１００日後には溶出量が０．０４ｍｇ／ｌまで上昇したが、環境基準値以下であった。硫黄含有量が２．３重量％以上である実施例２７〜２９では１００日後でも溶出は認められなかった。また、この実験結果は、加熱処理の間に２水石膏がＣａＳに還元され、６価クロムを還元する作用を呈した事をしめしている。 The analysis results are shown in Table 6. In Comparative Example 6 in which the sulfur content was 0.5% by weight, the elution amount exceeded the environmental standard value after 30 days. In Example 26 having a sulfur content of 1.4% by weight, the elution amount increased to 0.04 mg / l after 100 days, but was below the environmental standard value. In Examples 27 to 29 having a sulfur content of 2.3% by weight or more, no elution was observed even after 100 days. In addition, this experimental result indicates that dihydrate gypsum was reduced to CaS during the heat treatment, and the hexavalent chromium was reduced.
Claims (11)
11. The hexavalent chromium according to claim 1, wherein a value of (weight of reducing agent) / (weight of hexavalent chromium-containing substance) is in a range of 0.5 to 2. 11. Treatment method for contained substances.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5252176A (en) * | 1975-10-24 | 1977-04-26 | Kenjiro Takeshita | Method of making cr sludge harmless |
| JPH06269764A (en) * | 1993-03-22 | 1994-09-27 | Shibata Hario Glass Kk | Detoxicating treatment for solid waste containing hexavalent chromium |
| JPH10244242A (en) * | 1997-03-05 | 1998-09-14 | Okayama Ceramics Gijutsu Shinko Zaidan | Process of removing hexavalent chromium from heat-resistant substance containing hexavalent chromium |
| JPH11169814A (en) * | 1997-12-12 | 1999-06-29 | Chubu Electric Power Co Inc | Treatment of hexavalent chromium containing waste |
| JP2000086322A (en) * | 1998-09-17 | 2000-03-28 | Taiheiyo Cement Corp | Hexavalent chromium leach reducing agent for hydraulic material, and method for reducing hexavalent chromium leach |
| JP2001009414A (en) * | 1999-06-29 | 2001-01-16 | Shinagawa Refract Co Ltd | Detoxification treatment system for used chromium- containing refractory material |
| JP2001132930A (en) * | 1999-11-05 | 2001-05-18 | Mitsubishi Heavy Ind Ltd | Method and device for changing incineration ash to resource |
| JP2008273749A (en) * | 2006-11-30 | 2008-11-13 | Taiheiyo Material Kk | Artificial aggregate and its manufacturing method |
| JP2009132565A (en) * | 2007-11-30 | 2009-06-18 | Taiheiyo Material Kk | Method of manufacturing artificial aggregate |
| JP2009132564A (en) * | 2007-11-30 | 2009-06-18 | Taiheiyo Material Kk | Method of manufacturing artificial aggregate |
| CN102107205A (en) * | 2009-12-23 | 2011-06-29 | 湖南布鲁斯凯环保科技发展有限公司 | Method for harmlessly processing chromium slags |
-
2014
- 2014-09-10 JP JP2014184026A patent/JP6437769B2/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5252176A (en) * | 1975-10-24 | 1977-04-26 | Kenjiro Takeshita | Method of making cr sludge harmless |
| JPH06269764A (en) * | 1993-03-22 | 1994-09-27 | Shibata Hario Glass Kk | Detoxicating treatment for solid waste containing hexavalent chromium |
| JPH10244242A (en) * | 1997-03-05 | 1998-09-14 | Okayama Ceramics Gijutsu Shinko Zaidan | Process of removing hexavalent chromium from heat-resistant substance containing hexavalent chromium |
| JPH11169814A (en) * | 1997-12-12 | 1999-06-29 | Chubu Electric Power Co Inc | Treatment of hexavalent chromium containing waste |
| JP2000086322A (en) * | 1998-09-17 | 2000-03-28 | Taiheiyo Cement Corp | Hexavalent chromium leach reducing agent for hydraulic material, and method for reducing hexavalent chromium leach |
| JP2001009414A (en) * | 1999-06-29 | 2001-01-16 | Shinagawa Refract Co Ltd | Detoxification treatment system for used chromium- containing refractory material |
| JP2001132930A (en) * | 1999-11-05 | 2001-05-18 | Mitsubishi Heavy Ind Ltd | Method and device for changing incineration ash to resource |
| JP2008273749A (en) * | 2006-11-30 | 2008-11-13 | Taiheiyo Material Kk | Artificial aggregate and its manufacturing method |
| JP2009132565A (en) * | 2007-11-30 | 2009-06-18 | Taiheiyo Material Kk | Method of manufacturing artificial aggregate |
| JP2009132564A (en) * | 2007-11-30 | 2009-06-18 | Taiheiyo Material Kk | Method of manufacturing artificial aggregate |
| CN102107205A (en) * | 2009-12-23 | 2011-06-29 | 湖南布鲁斯凯环保科技发展有限公司 | Method for harmlessly processing chromium slags |
Non-Patent Citations (2)
| Title |
|---|
| 村上邦利ほか: "ARC測定結果の安全対策への応用", 安全工学, vol. 28, no. 5, JPN6018028927, 1989, pages 304 - 311, ISSN: 0003845803 * |
| 長谷良悦: "機器分析法とJIS分析法による石炭・コークスの元素分析国内共同実験(I)", 燃料協会誌, vol. 第67巻, 第6号, JPN6018028926, 1988, pages 418 - 429, ISSN: 0003845802 * |
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