JP2013141656A - Moisture absorbent and method for producing the same - Google Patents
Moisture absorbent and method for producing the same Download PDFInfo
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Abstract
Description
本発明は、複雑な設備を必要とすることなく比較的短時間で製造可能であり、かつ高い吸湿速度を示す生石灰を主成分とする吸湿剤、及びその製造方法に関するものである。 The present invention relates to a hygroscopic agent mainly composed of quicklime that can be produced in a relatively short time without requiring complicated equipment and exhibits a high moisture absorption rate, and a method for producing the same.
従来、生石灰は、食品の吸湿防止を目的とする乾燥剤として多く用いられている。また、電気電子機器などの工業分野においても利用が広がっている。真空断熱材中の吸湿剤として、一般には、高い吸湿速度を示し、吸湿能力も高いゼオライトが使用されてきたが、ゼオライトを真空下で使用する際には、使用前にゼオライト中の水分を十分に除去していなければ、真空下で逆に水分を放出し、真空度を下げてしまうため、使用に際して高温で処理を行わなければならなかった。そこで、水分を化学的に吸着することで真空下でも吸着した水分を放出しない生石灰を主成分とする吸湿剤の有用性が注目されるようになってきた。従来使用されている生石灰を主成分とする吸湿剤は、通常、石灰石を約９００℃以上に加熱し、酸化カルシウム（生石灰と同意語）と炭酸ガスに解離することにより得られていたが、加熱温度が低すぎると十分に分解が進行しないおそれがあるため、工業的には９００〜１３００℃に加熱され、その結果、炭酸ガスと解離した後の生石灰は焼結が進行し、高い吸湿速度を期待することができなかった。 Conventionally, quicklime is often used as a desiccant for the purpose of preventing moisture absorption of food. In addition, the use is expanding in industrial fields such as electrical and electronic equipment. As a hygroscopic agent in a vacuum heat insulating material, a zeolite having a high moisture absorption rate and a high moisture absorption ability has been generally used. However, when using the zeolite under vacuum, the moisture in the zeolite must be sufficiently used before use. If it is not removed, water is released under vacuum and the degree of vacuum is lowered, so that the treatment must be performed at a high temperature during use. Then, the usefulness of the hygroscopic agent which has quick lime as a main component which does not discharge | release the water | moisture content which adsorb | sucked under a vacuum by adsorb | sucking a water chemically has come to attract attention. Conventional hygroscopic agents mainly composed of quicklime have been obtained by heating limestone to about 900 ° C or higher and dissociating into calcium oxide (synonymous with quicklime) and carbon dioxide gas. Since decomposition may not proceed sufficiently if the temperature is too low, it is industrially heated to 900 to 1300 ° C. As a result, the quick lime after dissociation from carbon dioxide gas undergoes sintering and has a high moisture absorption rate. I couldn't expect it.
特許文献１（特開２００５−３３５９８７）や特許文献２（特開２００１−３５４４１４）によると、原料を消石灰とし、大気圧力以下の負圧力雰囲気下乃至真空下に保った密閉容器内で約３００〜６００℃に加熱し、生石灰と水に解離することで、非常に高い吸湿速度を示す生石灰が得られる報告がある。しかし、何れの方法も量産性に劣り、また製造装置も複雑になるため経済性に欠ける。また、一般に生石灰からなる吸湿剤は、生石灰を所定の大きさ（一般的に約１〜５ｍｍ）に破砕・分級してなる粒状物を包装材内に封入した状態で用いられるが、特許文献１や特許文献２に記載される粒子は、それより遙かに小さいものである。好適なハンドリング性を得るためには、粒子径が１．０ｍｍ以上の粒状であることが好ましい。特許文献３（特開２００５−２５４１１１）には、消石灰を原料とした直径１〜３ｍｍ程度の球状成形体を、ロータリーキルンで約６００〜９００℃にて４時間加熱・脱水し生石灰と水に解離することで、水分吸収能力が優れた生石灰が得られるとの報告がある。しかし、加熱を内燃式のロータリーキルンで行ったため、得られた生石灰が、ロータリーキルン中の主に炭酸ガス、水蒸気などを含んだ雰囲気ガスによって再炭酸化、再水和してしまう可能性があった。 According to Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-335987) and Patent Document 2 (Japanese Patent Application Laid-Open No. 2001-354414), the raw material is slaked lime and is about 300 to 300 in a sealed container kept under a negative pressure atmosphere or vacuum below atmospheric pressure. There is a report that quick lime showing a very high moisture absorption rate can be obtained by heating to 600 ° C. and dissociating into quick lime and water. However, any of these methods is inferior in mass productivity and lacks economic efficiency because the manufacturing apparatus becomes complicated. Moreover, generally the moisture absorbent which consists of quicklime is used in the state which enclosed the granular material which grind | pulverizes and classifies quicklime to a predetermined | prescribed magnitude | size (generally about 1-5 mm), but patent document 1 And the particle | grains described in patent document 2 are much smaller than it. In order to obtain a suitable handling property, it is preferable that the particle diameter is 1.0 mm or more. In Patent Document 3 (Japanese Patent Application Laid-Open No. 2005-254111), a spherical molded body having a diameter of about 1 to 3 mm made of slaked lime is heated and dehydrated at about 600 to 900 ° C. for 4 hours in a rotary kiln and dissociated into quick lime and water. Thus, there is a report that quick lime having an excellent water absorption ability can be obtained. However, since heating was performed with an internal combustion type rotary kiln, the obtained quicklime could be re-carbonated and rehydrated by atmospheric gas containing mainly carbon dioxide, water vapor, etc. in the rotary kiln.
よって本発明の目的は、複雑な設備を必要とすることなく比較的短時間で製造可能であり、高い吸湿速度を示す生石灰を主成分とする吸湿剤、及びその製造方法を提供することにある。
本発明の他の目的は、ハンドリング性の良好な生石灰を主成分とする吸湿剤の製造方法を提供することにある。
Therefore, an object of the present invention is to provide a hygroscopic agent mainly composed of quick lime that can be produced in a relatively short time without requiring complicated equipment and exhibits a high moisture absorption rate, and a method for producing the same. .
Another object of the present invention is to provide a method for producing a hygroscopic agent mainly composed of quicklime having good handling properties.
本発明者らは、ガスを流通させつつ、消石灰を５５０〜７５０℃の温度にて加熱することにより脱水して得られた生石灰が、温度２５℃、相対湿度９０％ＲＨに調整された大気中に１時間静置したときの質量増加量が、１ｇあたり０．２４０〜０．３００ｇの高い吸湿速度を示すことを見出し、本発明に到達したものである。 In the atmosphere where quick lime obtained by dehydrating slaked lime by heating at a temperature of 550 to 750 ° C. while circulating gas is adjusted to a temperature of 25 ° C. and a relative humidity of 90% RH. It was found that the increase in mass when allowed to stand for 1 hour showed a high moisture absorption rate of 0.240 to 0.300 g per gram, and reached the present invention.
消石灰を加熱・脱水する場合に、特許文献１，２に記載されているように加熱温度を低く抑えるとともに、消石灰から発生する水分の除去を加熱炉内の減圧によるのではなく、加熱炉にガスを流通させて素早く除去する方法を見出した。すなわち本発明に係る吸湿剤の製造方法は、ガスを流通させつつ、消石灰を５５０〜７５０℃の温度にて加熱することにより脱水反応を起こさせる工程を含む。消石灰の分解により発生した水分をガスの流通により除去すれば、炉内雰囲気の水の分圧は、概ね大気中と同程度となる。これにより再炭酸化・再水和の影響を少なくできるので、５５０〜７５０℃の低い温度の範囲で加熱し、脱水することが可能である。加熱温度が５５０℃未満では、脱水が生じないか十分に脱水が進行せず、７５０℃を超える高い温度では却って吸湿速度が減少する。これは、本発明はいかなる特別な理論にも拘束されるものではないが、７５０℃を超えると生石灰の焼結が進行してしまうためと考えられる。また本発明に係る吸湿剤の製造方法において利用される生石灰は、強熱減量が３重量％以下であり、ＣａＯ純分が高いので化学的に吸着できる水分量が大きく、よって吸湿量が多い。 When heating and dehydrating slaked lime, the heating temperature is kept low as described in Patent Documents 1 and 2, and the water generated from the slaked lime is removed not by depressurization in the heating furnace but by gas in the heating furnace. I found a method to remove it quickly. That is, the method for producing a hygroscopic agent according to the present invention includes a step of causing a dehydration reaction by heating slaked lime at a temperature of 550 to 750 ° C. while circulating gas. If the water generated by the decomposition of slaked lime is removed by the flow of gas, the partial pressure of water in the furnace atmosphere will be approximately the same as in the atmosphere. As a result, the influence of recarbonation / rehydration can be reduced, so that it can be dehydrated by heating in a low temperature range of 550 to 750 ° C. If the heating temperature is less than 550 ° C., dehydration does not occur or does not proceed sufficiently, and if the temperature exceeds 750 ° C., the moisture absorption rate decreases. This is because the present invention is not bound by any particular theory, but it is considered that the sintering of quick lime proceeds when the temperature exceeds 750 ° C. Further, the quicklime used in the method for producing a hygroscopic agent according to the present invention has a loss on ignition of 3% by weight or less, and since the pure CaO content is high, the amount of moisture that can be chemically adsorbed is large, and thus the amount of moisture absorption is large.
また本発明に係る吸湿剤の製造方法によると、炉内を減圧する必要がないため、大気圧下で消石灰を加熱・脱水して生石灰を生成する工程を実施することができ、これにより回分式でなく連続式での製造が可能となり、製造設備の簡略化及び製造時間の短縮を実現することができる。 Further, according to the method for producing a hygroscopic agent according to the present invention, since it is not necessary to depressurize the furnace, it is possible to carry out a step of heating and dehydrating slaked lime under atmospheric pressure to produce quick lime, thereby producing a batch type In addition, continuous production is possible, and production facilities can be simplified and production time can be shortened.
ガスを流通させつつ５５０〜７５０℃の温度にて加熱すると、消石灰は加熱開始後約１０分でほぼ９０重量％かそれ以上が生石灰と水に分解される。その後も加熱を続けるとさらに生石灰化する割合は１００％に近づくが、製品として求められる吸湿剤の性能や用途に応じ、加熱時間は調整されうる。加熱時間は４０分以内が好ましく、それ以上加熱しても吸湿速度の上昇は頭打ちになる。 When heated at a temperature of 550 to 750 ° C. while circulating gas, approximately 90% by weight or more of slaked lime is decomposed into quick lime and water in about 10 minutes after the start of heating. If heating is continued thereafter, the rate of quick calcification approaches 100%, but the heating time can be adjusted according to the performance and use of the hygroscopic agent required as a product. The heating time is preferably within 40 minutes, and even if the heating is continued for a long time, the increase in the moisture absorption rate reaches its peak.
ガスの流通量は、消石灰１．０g当たり標準状態で６２．５ｃｍ３／ｍｉｎ以上であることが好ましく、望ましくは標準状態で６２．５〜３２０ｃｍ３／ｍｉｎである。上述のように消石灰が加熱開始後１０分間で９０重量％が脱水されるとすると、消石灰１ｇから１分間あたり約０．０２１９ｇの水蒸気が発生し、約０．０２１９ｇの水蒸気は標準状態で２７．２ｃｍ３である。発生した水蒸気を生石灰の周囲から素早く除去するために、発生した水蒸気の体積比で約２倍かそれ以上のガスを流通させると吸湿剤の吸湿速度が良好となり、標準状態で６２．５ｃｍ３／ｍｉｎのガスを流通させることが好ましい。吸湿速度は、ガスの流通量を標準状態で３２０ｃｍ３／ｍｉｎ（水蒸気の体積比約１０倍）まで増やすとそれだけ吸湿速度が向上するが、それ以上増やしてもその分に見合った吸湿速度の向上は見られなかった。 The gas flow rate is preferably 62.5 cm 3 / min or more in a standard state per 1.0 g of slaked lime, and preferably 62.5 to 320 cm 3 / min in a standard state. As described above, assuming that 90% by weight of slaked lime is dehydrated in 10 minutes after the start of heating, about 0.0219 g of water vapor is generated from 1 g of slaked lime per minute, and about 0.0219 g of water vapor is 27. 2 cm 3 . In order to quickly remove the generated water vapor from the surroundings of quicklime, when a gas approximately twice or more in volume ratio of the generated water vapor is circulated, the moisture absorption rate of the hygroscopic agent becomes good, and 62.5 cm 3 / It is preferable to circulate min gas. The moisture absorption rate is increased by increasing the gas flow rate to 320 cm 3 / min (approximately 10 times the volume ratio of water vapor) in the standard state, but the moisture absorption rate is improved correspondingly even if it is further increased. Was not seen.
流通させるガスは、再水和や炭酸化がなるべく生じないように、好ましくは水蒸気や炭酸ガスや酸性ガスをほぼ含まない。水蒸気や炭酸ガスや酸性ガスをいずれもほぼ含まないガスは、典型的には何も加工や調整を経ていない空気（大気）であるが、圧縮空気や乾燥空気でもよい。あるいは、水蒸気等を実質的に含まない窒素ガスのような不活性ガスも好適である。 The gas to be circulated preferably does not substantially contain water vapor, carbon dioxide gas or acid gas so that rehydration or carbonation does not occur as much as possible. The gas that substantially does not contain any water vapor, carbon dioxide, or acid gas is typically air (atmosphere) that has not undergone any processing or adjustment, but may be compressed air or dry air. Alternatively, an inert gas such as nitrogen gas substantially free of water vapor or the like is also suitable.
原材料となる消石灰は粒状でも粉状でもよいが、粒状の消石灰を加熱・脱水して得られた粒状の生石灰をそのまま吸湿剤として使用するとすれば、ハンドリング性を考慮して粒子径１．０ｍｍ以上の粒状であることが好ましく、望ましくは径が１．２〜３．０ｍｍの円柱状に造粒されている。大きすぎると脱水に時間を要し、又は生石灰化が不十分になりやすい。 The raw slaked lime may be granular or powdery, but if the granular quick lime obtained by heating and dehydrating the granular slaked lime is used as it is as a hygroscopic agent, the particle diameter is 1.0 mm or more in consideration of handling properties. Preferably, it is granulated into a cylindrical shape having a diameter of 1.2 to 3.0 mm. If it is too large, it takes time for dehydration or quick calcification tends to be insufficient.
消石灰を加熱するための加熱炉の種類は限定されるものではなく、電気炉でも外熱式焼成炉でもよい。焼成炉の加熱源としては、一般の燃料すなわち重油、灯油、ＬＰＧ、再生油、ＲＰＦ、木材チップなどが挙げられる。加熱炉は外熱式ロータリーキルンでもよい。 The kind of heating furnace for heating slaked lime is not limited, and an electric furnace or an external heating type firing furnace may be used. Examples of the heating source of the firing furnace include general fuels such as heavy oil, kerosene, LPG, reclaimed oil, RPF, and wood chips. The heating furnace may be an external heating rotary kiln.
以上のように本発明に係る吸湿剤は、複雑な設備を必要とすることなく比較的短時間で製造可能であり、かつ高い吸湿速度を示す。また本発明に係る吸湿剤の製造方法は、複雑な設備を必要とすることなく比較的短時間で製造可能であるにも拘わらず、高い吸湿速度を有する吸湿剤を得ることができる。また本発明に係る吸湿剤の製造方法によると、ハンドリング性の良好な生石灰を主成分とする吸湿剤を製造することができる。 As described above, the hygroscopic agent according to the present invention can be produced in a relatively short time without requiring complicated equipment, and exhibits a high moisture absorption rate. In addition, although the method for producing a hygroscopic agent according to the present invention can be produced in a relatively short time without requiring complicated equipment, a hygroscopic agent having a high moisture absorption rate can be obtained. Moreover, according to the manufacturing method of the hygroscopic agent which concerns on this invention, the hygroscopic agent which has quick lime with favorable handleability as a main component can be manufactured.
以下、本発明に係る吸湿剤、及びその製造方法の最良の形態について詳細に説明する。なお、以下の説明は発明をより深く理解するためのものであって、特許請求の範囲を限定するためのものではない。 Hereinafter, the best mode of the hygroscopic agent according to the present invention and the production method thereof will be described in detail. The following description is for the purpose of understanding the invention more deeply and is not intended to limit the scope of the claims.
本発明に係る吸湿剤の製造方法において、加熱・脱水される消石灰は粒状又は粉状であるが、そのまま吸湿剤として使用可能な粒状の生石灰を得るためには、消石灰も粒状であり、かつ粒子径は１．０ｍｍ以上である。このような粒状の消石灰の原料としては、公知の如何なるものも用いることができるが、粒状の組成物を調整するに際して、工業用消石灰としてJISにて規定される６００μｍ以下に調整された粉体状の消石灰が有利に用いられる。 In the method for producing a hygroscopic agent according to the present invention, the slaked lime to be heated and dehydrated is granular or powdery, but in order to obtain granular quick lime that can be used as it is as a hygroscopic agent, the slaked lime is also granular and particles The diameter is 1.0 mm or more. As a raw material of such granular slaked lime, any known material can be used, but when adjusting the granular composition, it is a powder adjusted to 600 μm or less as stipulated by JIS as industrial slaked lime. Slaked lime is advantageously used.
粉体状の消石灰は、水とよく混練され、混練物を押出機、回転皿形造粒機、打錠機、ブリケッティングマシン等の既存の造粒機を使用して造粒することができる。粉体状の消石灰には、造粒物を作製する際の成形性向上等を目的として、水以外に適宜バインダーを配合して混練しても良い。適当なバインダーとしては、粉体を造粒する際に通常用いられている各種バインダー、例えば、ポリビニルアルコール、メチルセルロース、糖蜜、水ガラス、各種フェノール樹脂、フラン樹脂などの中から、適宜に選択、組み合わせて用いることができる。各バインダーは、選択したバインダーの種類や造粒方法に応じて、適宜配合されることとなる。 Powdered slaked lime is well kneaded with water, and the kneaded product can be granulated using an existing granulator such as an extruder, a rotating dish granulator, a tableting machine, or a briquetting machine. it can. The powdered slaked lime may be kneaded by appropriately blending a binder in addition to water for the purpose of improving moldability when producing a granulated product. As a suitable binder, various binders usually used for granulating powders, for example, polyvinyl alcohol, methyl cellulose, molasses, water glass, various phenol resins, furan resins, etc. are appropriately selected and combined. Can be used. Each binder is appropriately blended according to the selected binder type and granulation method.
次に消石灰の造粒物は、必要ならば乾燥の後、ガスを流通させつつ、５５０〜７５０℃の温度にて加熱し脱水される。ガスはほぼ水蒸気や炭酸ガスや酸性ガスを含まないものが好ましく、例えば空気や窒素ガスが利用できる。ガスの流通量は、消石灰１ｇあたり標準状態で６２．５ｃｍ３／ｍｉｎ以上、好ましくは６２．５〜３２０ｃｍ３／ｍｉｎである。加熱・脱水の工程は有利に大気圧下で行うことができる。加熱は５５０〜７５０℃の温度範囲、好ましくは６００〜６５０℃の範囲の温度で行われる。消石灰の加熱時間は１０分以上である。 Next, the granulated product of slaked lime is dehydrated by heating at a temperature of 550 to 750 ° C. while allowing gas to flow after drying if necessary. The gas is preferably substantially free of water vapor, carbon dioxide, or acid gas. For example, air or nitrogen gas can be used. The gas flow rate is 62.5 cm 3 / min or more, preferably 62.5 to 320 cm 3 / min in a standard state per 1 g of slaked lime. The heating / dehydration step can be advantageously carried out at atmospheric pressure. Heating is performed at a temperature in the range of 550 to 750 ° C, preferably in the range of 600 to 650 ° C. The heating time of slaked lime is 10 minutes or more.
以上のようにして製造した生石灰は、温度２５℃、相対湿度９０％ＲＨに調整された大気中に１時間静置したときの質量増加量が、１ｇあたり０．２４０〜０．３００ｇを示すような高い吸湿性能を有しうる。このときの水和率は、７５〜９３．８重量％である。水和率とは、１ｇの生石灰が水和できる理論上の水分量０．３２ｇに対する、水和による質量増加量の割合を言う。 The quicklime produced as described above has a mass increase of 0.240 to 0.300 g per gram when left in an atmosphere adjusted to a temperature of 25 ° C. and a relative humidity of 90% RH for 1 hour. High moisture absorption performance. The hydration rate at this time is 75 to 93.8% by weight. Hydration rate refers to the ratio of the amount of mass increase due to hydration to the theoretical water content of 0.32 g where 1 g of quicklime can be hydrated.
得られた生石灰は吸湿剤の主成分として利用される。生石灰を含有する吸湿剤は、粉化した粉が食品や電子機器等に影響しないように、不織布や樹脂フィルム製の袋に封入され、あるいは樹脂製の箱に収納されて使用される。この吸湿剤は、高い吸湿速度を示すことから、例えば、真空断熱材用の製造工程において、減圧密閉後に芯材表面に付着した吸着水が気化することによる真空断熱材内圧の上昇抑制に有利に使用することができる。 The obtained quicklime is used as a main component of the hygroscopic agent. The hygroscopic agent containing quicklime is used by being encapsulated in a non-woven fabric or a resin film bag or housed in a resin box so that the powdered powder does not affect food or electronic equipment. Since this hygroscopic agent exhibits a high moisture absorption rate, for example, in a manufacturing process for a vacuum heat insulating material, it is advantageous for suppressing an increase in the internal pressure of the vacuum heat insulating material due to vaporization of adsorbed water adhering to the core material surface after sealing under reduced pressure. Can be used.
［サイズの影響］
［実施例１−１］
ＪＩＳ特号消石灰粉末（Ｃａ（ＯＨ）２純分９７．５％、矢橋工業株式会社）：６５重量部、水：３５重量部をよく混ぜ、スクリュー型押出造粒機（不二パウダル株式会社
ペレッターダブルＥＸＤＦ−６０型 スクリュー回転数４０ｒｐｍ）で直径１．５ｍｍの湿潤粒状消石灰を作製し、さらに１５０℃の熱風乾燥機（ヤマト科学株式会社 送風定温恒温器ＤＮ６３Ｈ型）で３時間乾燥して乾燥粒状消石灰を得た。この粒状消石灰８ｇを直径９０ｍｍ、長さ５００ｍｍの静止管状炉（真陽理化学器機株式会社製
高真空式 小型真空雰囲気炉 ＳＳＨ型）の加熱帯の中央部あたりに幅８０ｍｍに平らに入れ、窒素ガス（純度９９％以上、水蒸気１％未満）を標準状態１０，０００ｃｍ３／ｍｉｎ（以下ガスの量はいずれも標準状態で表す）で流入しながら、炉内温度調節用の制御装置の指針値（炉内壁温度を測定）がほぼ６００℃を示す状態を維持しつつ３０分間加熱して、粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１．０ｇあたり１，２５０ｃｍ３／ｍｉｎである。
［実施例１−２］
実施例１−１において、湿潤粒状消石灰サイズを直径１．７ｍｍとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例１−３］
実施例１−１において、湿潤粒状消石灰サイズを直径２．０ｍｍとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例１−４］
実施例１−１において、湿潤粒状消石灰サイズを直径３．０ｍｍとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例１−５］
実施例１−１において、加熱温度を６５０℃とする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例１−６］
実施例１−１において、湿潤粒状消石灰サイズを直径１．７ｍｍ、加熱温度を６５０℃とする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
[Influence of size]
[Example 1-1]
JIS special slaked lime powder (Ca (OH) 2 pure content 97.5%, Yabashi Kogyo Co., Ltd.): 65 parts by weight, water: 35 parts by weight are mixed well, screw type extrusion granulator (Fuji Powdal Co., Ltd. We produce wet granular slaked lime with a diameter of 1.5 mm with a turdable EXDF-60 type screw rotation speed of 40 rpm, and further dry for 3 hours with a hot air dryer (Yamato Scientific Co., Ltd., blown constant temperature thermostat DN63H type) at 150 ° C. Granular slaked lime was obtained. 8 g of this granular slaked lime is flattened to a width of 80 mm around the center of the heating zone of a stationary tubular furnace (manufactured by Shinyo Chemical Co., Ltd., high vacuum type small vacuum atmosphere furnace SSH type) having a diameter of 90 mm and a length of 500 mm. (Purity 99% or more and less than 1% water vapor) at a standard state of 10,000 cm 3 / min (hereinafter, the amounts of gas are all expressed in the standard state) Heating was performed for 30 minutes while maintaining a state in which the temperature of the furnace inner wall was approximately 600 ° C., and a hygroscopic agent made of granular quicklime was produced. The circulating nitrogen gas is 1,250 cm 3 / min per 1.0 g of slaked lime.
[Example 1-2]
In Example 1-1, the hygroscopic agent which consists of granular quicklime was manufactured by performing the same operation as Example 1-1 except the wet granular slaked lime size being 1.7 mm in diameter.
[Example 1-3]
In Example 1-1, the hygroscopic agent which consists of granular quicklime was manufactured by performing the same operation as Example 1-1 except the wet granular slaked lime size being 2.0 mm in diameter.
[Example 1-4]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the wet granular slaked lime size was 3.0 mm in diameter.
[Example 1-5]
In Example 1-1, the hygroscopic agent which consists of granular quicklime was manufactured by performing the same operation as Example 1-1 except heating temperature being 650 degreeC.
[Example 1-6]
In Example 1-1, the hygroscopic agent which consists of granular quick lime was manufactured by performing the same operation as Example 1-1 except the wet granular slaked lime size being 1.7 mm in diameter, and heating temperature being 650 degreeC.
［吸湿速度の評価］
各実施例の粒状生石灰からなる吸湿剤の吸湿速度を、以下の方法により評価した。
試料の粒状生石灰からなる吸湿剤３．０ｇを、温度２５℃、相対湿度９０％ＲＨに調整した低温恒温恒湿器（株式会社東洋製作所 ＴＨＥ０５１ＦＡ）に入れ、１時間静置した後の重量を測定して、１ｇあたりの重量増加量を算出した。結果を表１に示す。
[Evaluation of moisture absorption rate]
The moisture absorption rate of the hygroscopic agent composed of granular quicklime of each example was evaluated by the following method.
Measure the weight after placing 3.0 g of a hygroscopic agent composed of granular quicklime as a sample in a low-temperature thermo-hygrostat (Toyo Seisakusho THE051FA) adjusted to a temperature of 25 ° C. and a relative humidity of 90% RH. Then, the weight increase per gram was calculated. The results are shown in Table 1.
［吸湿量の評価］
生石灰を含む吸湿剤の吸湿量はＣａＯ純分で決まるので、強熱減量が少ないということは吸湿量が多いことを意味する。強熱減量は、以下の方法により測定した。
磁器るつぼを１０００±５０℃の電気炉（株式会社東京本山商会 ＳＳ−１２２０ＤＺ）で３０分間強熱し、デシケーター中で放冷した後、０．１ｍｇの単位まで質量（Ａ）を計測した。磁器るつぼに約１ｇの試料を入れて０．１ｍｇの単位まで質量（Ｂ）を計測し、１０００±５０℃の電気炉で６０分間強熱した。強熱後、磁器るつぼを電気炉より直ちにデシケーターに入れて密封し、１０分間放冷した。放冷後、デシケーターの活栓を開いて空気を入れた後、磁器るつぼを取り出し質量（Ｃ）を０．１ｍｇの単位まで手早く計測した。強熱減量（％）は以下の式により求めた。
強熱減量（％）＝（Ｂ−Ｃ）／（Ｂ−Ａ）×１００
結果を表１に示す。
[Evaluation of moisture absorption]
Since the moisture absorption amount of the hygroscopic agent containing quicklime is determined by the CaO pure content, the fact that the ignition loss is small means that the moisture absorption amount is large. The ignition loss was measured by the following method.
The porcelain crucible was ignited for 30 minutes in an electric furnace (Tokyo Motoyama Shokai SS-1220DZ) at 1000 ± 50 ° C., allowed to cool in a desiccator, and then the mass (A) was measured to a unit of 0.1 mg. About 1 g of a sample was put in a porcelain crucible, the mass (B) was measured to a unit of 0.1 mg, and ignited in an electric furnace at 1000 ± 50 ° C. for 60 minutes. After ignition, the porcelain crucible was immediately put into a desiccator from an electric furnace and sealed, and allowed to cool for 10 minutes. After standing to cool, the stopcock of the desiccator was opened and air was introduced. Then, the porcelain crucible was taken out and the mass (C) was quickly measured to a unit of 0.1 mg. The ignition loss (%) was determined by the following formula.
Loss on ignition (%) = (BC) / (BA) × 100
The results are shown in Table 1.
表１の結果より、各実施例はサイズの変化に影響されることなく、吸湿速度及び吸湿量において良好な範囲内の値を示した。よって径が１．２〜３．０ｍｍの円柱状に造粒された消石灰を原材料として、ハンドリング性の良好なサイズの生石灰を使用した吸湿剤を得ることができることが分かった。 From the results in Table 1, each example showed a value within a good range in the moisture absorption rate and the amount of moisture absorption without being affected by the change in size. Therefore, it turned out that the hygroscopic agent which used quick lime of the size with favorable handling property can be obtained by using as raw material the slaked lime granulated in the column shape whose diameter is 1.2-3.0 mm.
［ガス流量の影響］
［比較例２−１］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を０ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例２−２］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を５０ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり６．２５ｃｍ３／ｍｉｎである。
［比較例２−３］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を１６０ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり２０ｃｍ３／ｍｉｎである。
［比較例２−４］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を４００ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり５０ｃｍ３／ｍｉｎである。
［実施例２−１］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を５００ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり６２．５ｃｍ３／ｍｉｎである。
［実施例２−２］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を１，０００ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり１２５ｃｍ３／ｍｉｎである。
［実施例２−３］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を２，５００ｃｍ３／ｍｉｎとする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり３１２．５ｃｍ３／ｍｉｎである。
［実施例２−４］
実施例１−１において、加熱温度を６５０℃、流通させる窒素ガス量を１０，０００ｃｍ３／ｍｉｎとする以外は、実施例１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する窒素ガスは、消石灰１ｇあたり１，２５０ｃｍ３／ｍｉｎである。
［比較例２−５］
実施例１−１において、流通させる窒素ガスをブタンガスの燃焼ガスを模擬したＣＯ２：８％と水蒸気：１２％とする以外は、実施例１−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。流通する模擬ガスは消石灰１ｇあたり１２５０ｃｍ３／ｍｉｎである。
各実施例・比較例については、上述の［吸湿速度の評価］の試験を行った。結果を表２に示す。
[Influence of gas flow rate]
[Comparative Example 2-1]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 0 cm 3 / min.
[Comparative Example 2-2]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 50 cm 3 / min. The circulating nitrogen gas is 6.25 cm 3 / min per 1 g of slaked lime.
[Comparative Example 2-3]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 160 cm 3 / min. The circulating nitrogen gas is 20 cm 3 / min per 1 g of slaked lime.
[Comparative Example 2-4]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 400 cm 3 / min. The circulating nitrogen gas is 50 cm 3 / min per 1 g of slaked lime.
[Example 2-1]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 500 cm 3 / min. The circulating nitrogen gas is 62.5 cm 3 / min per 1 g of slaked lime.
[Example 2-2]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 1,000 cm 3 / min. . The circulating nitrogen gas is 125 cm 3 / min per 1 g of slaked lime.
[Example 2-3]
In Example 1-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as Example 1-1 except that the heating temperature was 650 ° C. and the amount of nitrogen gas to be circulated was 2,500 cm 3 / min. . The circulating nitrogen gas is 312.5 cm 3 / min per 1 g of slaked lime.
[Example 2-4]
In Example 1-1, the hygroscopic agent which consists of granular quicklime was manufactured by performing the same operation as Example 1 except the heating temperature being 650 degreeC and the amount of nitrogen gas to distribute | circulate being 10,000 cm < 3 > / min. The circulating nitrogen gas is 1,250 cm 3 / min per 1 g of slaked lime.
[Comparative Example 2-5]
In Example 1-1, CO with nitrogen gas circulating simulating the combustion gas butane 2: 8% and steam: except that 12%, moisture absorption made of granular quicklime Follow the same procedure as in Example 1-1 An agent was produced. The simulated gas to be circulated is 1250 cm 3 / min per 1 g of slaked lime.
About each Example and the comparative example, the test of the above-mentioned [Evaluation of moisture absorption speed] was performed. The results are shown in Table 2.
表２より、ガスの流量は吸湿剤の吸湿速度に影響することがわかった。温度２５℃、相対湿度９０％ＲＨに調整された大気中に１時間静置したときの質量増加量が１ｇあたり０．２４０ｇ以上のような好ましい吸湿速度を実現するには、ガス流量は標準状態で６２．５ｃｍ３／ｍｉｎ以上が必要となり、望ましくは標準状態で６２．５〜３２０ｃｍ３／ｍｉｎであった。消石灰が加熱開始後１０分間で９０重量％が脱水されるとすると、消石灰１ｇから１分間あたり約０．０２１９ｇの水蒸気が発生し、約０．０２１９ｇの水蒸気は標準状態で２７．２ｃｍ３である。発生した水蒸気を生石灰の周囲から素早く除去するために、発生した水蒸気の体積比で約２倍かそれ以上のガスを流通させると吸湿速度が良好となり、標準状態で６２．５ｃｍ３／ｍｉｎのガスを流通させると所望の吸湿速度が得られた。ガスの流通量を標準状態で３２０ｃｍ３／ｍｉｎ（水蒸気の体積比約１０倍）まで増やすとそれだけ吸湿速度が向上するが、それ以上増やしてもその分に見合った吸湿速度の向上は見られなかった。またブタンガスの燃焼ガスを模擬した模擬ガスを流通させても、空気や窒素ガスに比較して吸湿速度の良好な吸湿剤は得られなかった。これは、模擬ガスにかなりの割合で含まれる水蒸気が消石灰の脱水を阻害し、あるいは生石灰に再水和したためと考えられる。また、模擬ガスにかなりの割合で含まれる炭酸ガスにより、炭酸化が生じたためと考えられる。 From Table 2, it was found that the gas flow rate affects the moisture absorption rate of the moisture absorbent. In order to realize a preferable moisture absorption rate such that the amount of increase in mass is 0.240 g or more per gram when left in an atmosphere adjusted to a temperature of 25 ° C. and a relative humidity of 90% RH for 1 hour, the gas flow rate is in a standard state. 62.5 cm 3 / min or more is required, and preferably 62.5 to 320 cm 3 / min in the standard state. If 90% by weight of slaked lime is dehydrated in 10 minutes after the start of heating, about 0.0219 g of water vapor is generated from 1 g of slaked lime per minute, and about 0.0219 g of water vapor is 27.2 cm 3 in a standard state. . In order to quickly remove the generated water vapor from the surroundings of quicklime, the gas absorption rate becomes good when a gas having a volume ratio of the generated water vapor of about twice or more is circulated, and a gas of 62.5 cm 3 / min in the standard state. The desired moisture absorption rate was obtained. Increasing the gas flow rate to 320 cm 3 / min (approximately 10 times the volume ratio of water vapor) in the standard state will improve the moisture absorption rate, but even if it is increased further, the moisture absorption rate will not be improved accordingly. It was. Further, even when a simulated gas simulating the combustion gas of butane gas was circulated, a hygroscopic agent having a better moisture absorption rate than air or nitrogen gas could not be obtained. This is presumably because water vapor contained in the simulated gas in a considerable proportion hindered dehydration of slaked lime or rehydrated to quick lime. In addition, it is considered that carbonation occurred due to carbon dioxide contained in the simulated gas in a considerable proportion.
［温度の影響］
［実施例３−１］
ＪＩＳ特号消石灰粉末（Ｃａ（ＯＨ）２純分９７．５％、矢橋工業株式会社）：６５重量部、水：３５重量部をよく混ぜ、スクリュー型押出造粒機（不二パウダル株式会社
ペレッターダブルＥＸＤＦ−６０型 スクリュー回転数４０ｒｐｍ）で直径１．５ｍｍの湿潤粒状消石灰を作製し、さらに１５０℃の熱風乾燥機（ヤマト科学株式会社 送風定温恒温器ＤＮ６３Ｈ型）で３時間乾燥することで乾燥粒状消石灰を得た。この粒状消石灰８ｇを直径９０ｍｍ、長さ５００ｍｍの静止管状炉（真陽理化学器機株式会社
高真空式 小型真空雰囲気炉 ＳＳＨ型）の加熱帯の中央部あたりに幅８０ｍｍに平らに入れ、空気を標準状態１０，０００ｃｍ３／ｍｉｎで流入しながら、５５０℃の温度にて３０分間加熱して、粒状生石灰からなる吸湿剤を製造した。流通する空気は、消石灰１ｇあたり１，２５０ｃｍ３／ｍｉｎである。
［実施例３−２］
実施例３−１において、加熱温度を６００℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例３−３］
実施例３−１において、加熱温度を６５０℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例３−４］
実施例３−１において、加熱温度を７００℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［実施例３−５］
実施例３−１において、加熱温度を７５０℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例３−０］
実施例３−１において、加熱温度を４５０℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例３−１］
実施例３−１において、加熱温度を５００℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例３−２］
実施例３−１において、加熱温度を８００℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例３−３］
実施例３−１において、加熱温度を８５０℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
［比較例３−４］
実施例３−１において、加熱温度を９００℃とする以外は、実施例３−１と同じ操作を行って粒状生石灰からなる吸湿剤を製造した。
各実施例・比較例について上述の［吸湿速度の評価］及び［吸湿量の評価］の各試験を行った。結果を表３に示す。
[Influence of temperature]
[Example 3-1]
JIS special slaked lime powder (Ca (OH) 2 pure content 97.5%, Yabashi Kogyo Co., Ltd.): 65 parts by weight, water: 35 parts by weight are mixed well, screw type extrusion granulator (Fuji Powdal Co., Ltd. By producing wet granular slaked lime with a diameter of 1.5 mm with a Turdable EXDF-60 type screw rotation speed of 40 rpm, and further drying for 3 hours with a hot air dryer (Yamato Scientific Co., Ltd. blown constant temperature thermostat DN63H type) at 150 ° C. Dry granular slaked lime was obtained. 8g of this granular slaked lime is flattened to a width of 80mm around the center of the heating zone of a stationary tubular furnace (Shinyo Rika Kaiki Co., Ltd. high vacuum type small vacuum atmosphere furnace SSH type) with a diameter of 90mm and a length of 500mm. While flowing in a state of 10,000 cm 3 / min, heating was performed at a temperature of 550 ° C. for 30 minutes to produce a hygroscopic agent made of granular quicklime. The circulating air is 1,250 cm 3 / min per 1 g of slaked lime.
[Example 3-2]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 600 ° C.
[Example 3-3]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 650 ° C.
[Example 3-4]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 700 ° C.
[Example 3-5]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 750 ° C.
[Comparative Example 3-0]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 450 ° C.
[Comparative Example 3-1]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 500 ° C.
[Comparative Example 3-2]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 800 ° C.
[Comparative Example 3-3]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 850 ° C.
[Comparative Example 3-4]
In Example 3-1, a hygroscopic agent made of granular quicklime was produced by performing the same operation as in Example 3-1, except that the heating temperature was 900 ° C.
Each test of the above-mentioned [Evaluation of moisture absorption rate] and [Evaluation of moisture absorption amount] was performed for each of the examples and comparative examples. The results are shown in Table 3.
表１の結果から、５００℃以下の低い温度で加熱された生石灰からなる吸湿剤（比較例３−１、２）は、原料消石灰の生石灰と水への分解が十分に進行しないため、吸湿速度が低く（１ｇあたりの重量増量０．２４０ｇ以下）、吸湿量も少ない（強熱減量３％以上）。逆に８００℃以上の高い温度に加熱すると（比較例３−２、３、４）、生石灰の焼結が進行してしまい、吸湿速度及び吸湿量が劣ることになる。 From the results shown in Table 1, the moisture absorption agent composed of quick lime heated at a low temperature of 500 ° C. or less (Comparative Examples 3-1 and 2) does not sufficiently decompose the raw slaked lime into quick lime and water. Is low (weight gain of 0.240 g or less per gram) and moisture absorption is small (ignition loss is 3% or more). Conversely, when heated to a high temperature of 800 ° C. or higher (Comparative Examples 3-2, 3 and 4), quick lime sintering proceeds, resulting in inferior moisture absorption rate and moisture absorption.
［連続炉による加熱・脱水］
［実施例４］
ＪＩＳ特号消石灰粉末（Ｃａ（ＯＨ）２純分９７．５％、矢橋工業株式会社製）：６５重量部、水：３５重量部をよく混ぜ、スクリュー型押出造粒機（不二パウダル株式会社
ペレッターダブルＥＸＤＦ−６０型 スクリュー回転数４０ｒｐｍ）で直径１．５ｍｍの湿潤粒状消石灰を作製し、さらに１５０℃の熱風乾燥機（ヤマト科学株式会社 送風定温恒温器ＤＮ６３Ｈ型）で３時間乾燥することで乾燥粒状消石灰を得た。この粒状消石灰を内径１２５ｍｍ、長さ１３９０ｍｍ、加熱帯長さ８００ｍｍの外熱式ロータリーキルン（中央化工機株式会社製
外熱式ＬＡＢＯ小型機 ＪＣＥ−１２５−１型）にて、大気２０，０００ｃｍ３／ｍｉｎを流通しながら、外熱炉温度８００℃の設定にて加熱して、粒状生石灰からなる吸湿剤を製造した。併せて炉内物質温度を、加熱帯始点よりの距離毎に熱電対（林電工株式会社
ＳＫシース熱電対）にて測定した。流通する空気は、消石灰１ｇあたり３３３ｃｍ３／ｍｉｎである。
製造した吸湿剤について上述の［吸湿速度の評価］を行った。結果を表４に示す。
[Heating and dehydration in a continuous furnace]
[Example 4]
JIS special slaked lime powder (Ca (OH) 2 pure content 97.5%, manufactured by Yabashi Kogyo Co., Ltd.): 65 parts by weight, water: 35 parts by weight are mixed well, screw type extrusion granulator (Fuji Powdal Co., Ltd.) Prepare wet granular slaked lime with a diameter of 1.5 mm by pelleter double EXDF-60 type screw rotation speed 40 rpm), and further dry for 3 hours with a hot air dryer (Yamato Scientific Co., Ltd. blown constant temperature thermostat DN63H type) at 150 ° C. The dried granular slaked lime was obtained. This granular slaked lime is 20,000 cm 3 / atmosphere in an externally heated rotary kiln having an inner diameter of 125 mm, a length of 1390 mm, and a heating zone length of 800 mm (Chuo Kakoki Co., Ltd., externally heated LABO small machine JCE-125-1 type). While circulating min, it was heated at a setting of an external heating furnace temperature of 800 ° C. to produce a moisture absorbent made of granular quicklime. In addition, the in-furnace material temperature was measured with a thermocouple (Rinden Electric Co., Ltd. SK sheathed thermocouple) for each distance from the heating zone start point. The circulating air is 333 cm 3 / min per 1 g of slaked lime.
The above-mentioned [Evaluation of moisture absorption rate] was performed on the manufactured hygroscopic agent. The results are shown in Table 4.
表４の通り、大気圧下で連続式の加熱・脱水を行ったとしても、吸湿剤として利用可能な吸湿速度に優れた生石灰を得ることができることが実証された。 As shown in Table 4, it was demonstrated that quick lime excellent in moisture absorption rate that can be used as a moisture absorbent can be obtained even if continuous heating and dehydration are performed under atmospheric pressure.
以上、本発明の実施例について説明したが、本発明は上記実施例によって限定されることはなく、本発明の要旨の範囲内において、適宜変形実施が可能であることは言うまでもない。 As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention is not limited by the said Example, A deformation | transformation implementation is possible suitably in the range of the summary of this invention.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2017150426A1 (en) * | 2016-02-29 | 2017-09-08 | 宇部マテリアルズ株式会社 | Calcium oxide powder and adsorbent, and method for producing calcium oxide powder |
| JPWO2017029727A1 (en) * | 2015-08-19 | 2018-04-05 | 三菱電機株式会社 | Vacuum insulation and insulation box |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPWO2017029727A1 (en) * | 2015-08-19 | 2018-04-05 | 三菱電機株式会社 | Vacuum insulation and insulation box |
| WO2017150426A1 (en) * | 2016-02-29 | 2017-09-08 | 宇部マテリアルズ株式会社 | Calcium oxide powder and adsorbent, and method for producing calcium oxide powder |
| CN108698848A (en) * | 2016-02-29 | 2018-10-23 | 宇部材料工业株式会社 | The manufacturing method of lime powder and adsorbent and lime powder |
| JPWO2017150426A1 (en) * | 2016-02-29 | 2018-12-20 | 宇部マテリアルズ株式会社 | Calcium oxide powder, adsorbent and method for producing calcium oxide powder |
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