JP2004330130A

JP2004330130A - Method for freezing liquid material on internal surface of vertical tube of freeze dryer, and freeze dryer to be used for it

Info

Publication number: JP2004330130A
Application number: JP2003131483A
Authority: JP
Inventors: Hiroshi Hosomi; 博細見; Yasuhiro Ikeda; 康博池田
Original assignee: Kyowa Vacuum Engineering Co Ltd
Current assignee: Kyowa Vacuum Engineering Co Ltd
Priority date: 2003-05-09
Filing date: 2003-05-09
Publication date: 2004-11-25
Anticipated expiration: 2023-05-09
Also published as: JP4122256B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for freeze-drying where a liquid material is frozen on an internal surface of a vertical tube forming a hollow pipe and freeze-dried under vacuum, and freezing the liquid supplied into the tube on the internal surface of the tube forming a hollow pipe is performed leaving an amount of unfrozen liquid very trifling at the end of a freezing step. <P>SOLUTION: The method for freezing the liquid material on the internal surface of the vertical tube of the freeze dryer comprises forming a tube-like frozen layer by spraying the liquid material to the internal surface 10 of the vertical tube 1 with a spray nozzle (d), collecting a falling unfrozen liquid material in a liquid holder L in a pipe (k) connected to the bottom end of the vertical tube 1, transferring the collected liquid material to another tank using a recovery line (e), switching the connections of the first and second tanks (a), (b) with a supply line (c) and the recovery line (e) to continue to spray the liquid material from the spray nozzle (d) and recover the unfrozen liquid, and repeating the above operations to freeze the liquid material on the internal surface of the vertical tube 1 forming a hollow pipe. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明が属する技術分野】
本発明は、原材料から調整した薬液等の液状の被乾燥材料を、外周面が不凍熱媒流体により加熱と冷却が可能となっている竪方向のチューブの内壁面に、所定厚さの凍結層に凍結させ、その凍結層を真空下において、昇華熱の供給により凍結乾燥させる凍結乾燥手段において、液状の被乾燥材料を、チューブの内壁面に凍結層として凍結させる凍結手段に関する。
【０００２】
【従来の技術】
液状の被乾燥材料を、竪方向のチューブの内壁面に凍結層として凍結させ、それを真空下において凍結乾燥させる凍結乾燥手段において、液状の被乾燥材料のチューブの内壁面に対する凍結は、従前にあっては、例えば、特公平６−３５９１１号公報にある手段より行われている。
【０００３】
この手段は、図１・および図２にあるように、被凍結乾燥材料に熱を供給する加熱面を兼ねる冷却面を、竪型チューブ１の内壁面１０により構成し、これを収容する乾燥室の隔壁を竪型筒状体２の筒壁２０により形成し、竪型チューブ１の内壁面１０に凍結させた被乾燥材料から昇華させる水蒸気を捕集して真空に保つトラップ（蒸気凝結器）３０を、前記乾燥室を形成する竪型筒状体２の筒壁２０の外周に配設し、そのトラップ３０の外周を、外筒状の機壁４で囲い、その機壁４と前記乾燥室の隔壁を形成する竪型筒状体２の筒壁２０との間をトラップ室３に形成し、それの竪型筒状体２の筒壁２０の内周面と竪型チューブ１の外周面との間の空間に、不凍熱媒流体を循環させて、竪型チューブ１の内壁面１０の冷却面の加熱と冷却とを可能として、竪型チューブ１の内壁面１０に凍結させる被乾燥材料を真空下において凍結乾燥させる形態の真空凍結乾燥装置Ａに構成する。
【０００４】
そして、これの竪型チューブ１の内周面１０に対し被乾燥材料を凍結層として凍結させるのは、図１にあるように、竪型チューブ１の底面側の開口を、ヒンジ５０中心に開閉回動する扉５の上面側との間に、液状に調整した被乾燥材料の流路５１を形成して、この流路５１に連通させておき、この流路５１に供給管１１から液状の被乾燥材料を供給して、竪型チューブ１の内腔に押し上げ、それのレベルが竪型チューブ１の上端側の開口近くになったところで、被乾燥材料の供給を停める。
【０００５】
この状態で、竪型筒状体２の内周面２０と竪型チューブ１の外周面との間に、ブラインノズル２１から送給して排出管２２から排出させる不凍熱媒流体の循環による冷却で、この液状の被乾燥材料を竪型チューブ１の内壁面１０に凍結させる。
【０００６】
これによる被乾燥材料の竪型チューブ１の内壁面に凍結する凍結層の厚さが所定の厚さに達したところで、凍結の行程を止め、未凍の被乾燥材料を供給管１１から抜き出し、竪型チューブ１内に所定の厚さの凍結層が中空のパイプ状に残る状態として、凍結行程を終了させる。
【０００７】
次いで、乾燥行程に移行させ、中空パイプ状の凍結層に凍結した被乾燥材料の内面から水蒸気を昇華させて乾燥させるようにしている。
【０００８】
【発明が解決しようとする課題】
上述の、竪型チューブ１内に液状の被乾燥材料を押し上げるように、所定のレベルまで張り込んで、それを竪型チューブ１の内壁面１０に凍結させ、その凍結層が所定の厚さになったところで、未凍液を落として、竪型チューブ１の内壁面１０に、中空パイプ状に液材料を凍結させる手段には、液材料を凍結させたときに抜き出す未凍液がかなりの量となることで、この抜き出して廃棄することになる未凍液による損失が大きい問題がある。
【０００９】
この液材料を竪型チューブ１内面に凍結させた後に抜き出す未凍液の量の、竪型チューブ１内に供給する液材料の量に対する割合は、竪型チューブ１を直径８５ミリとし、これに１０数ミリの厚さに液材料を凍結させる場合でいえば、殆ど３分の２に近い量となる。
【００１０】
この抜き出す未凍液の量は、竪型チューブ１の内周面に凍結させる液材料の凍結層の厚さを厚くすることで少なくし得るが、竪型チューブ１内面に凍結させる液材料を、中空のパイプ状に形成するのは、乾燥行程時にそれの内周面を水蒸気の昇華面とするためであり、凍結層からの昇華が、効率よく、かつ、凍結層の各部位から均一に行われるようにするには、中空のパイプ状に竪型チューブ１の内壁面１０に凍結させる液材料の凍結層の中心穴の径を、凍結層の厚さに対し充分に広くしなければならないので、液材料を凍結させた後に抜き出す未凍液の量は、竪型チューブ１内に供給する液材料の全量に対してかなりの量となる。
【００１１】
真空乾燥装置が多連に並設してあって、第１位の装置で抜き出した未凍液を、第２位の装置に供給することで、損失にならないようにはなるが、最後位の装置において抜き出した未凍液は、凍結させるべき竪型チューブ１がないことで、使用できない。そして、液材料が薬液のように、液材料に調整した後の品質変化などで保存期間に制約がある場合には、廃棄するより他はなく、凍結乾燥により製造する製品には、例えば耳かき一杯で数十万円もするものがあるので、この凍結させ得ないで廃棄することになる未凍液の量を少なくすることは、大きな問題となる。
【００１２】
本発明は、この問題を解消するためになされたものであって、液材料を竪方向のチューブの内壁面に、中空のパイプ状に凍結させ、これを真空下において昇華熱の供給により、凍結乾燥させる凍結乾燥手段において、チューブ内に供給した液材料を、チューブの内壁面に中空のパイプ状に凍結させるのが、凍結行程の終了時に未凍のまま残す未凍液の量を、極く少なくして行えるようにする手段を提供することを目的とする。
【００１３】
【課題を解決するための手段】
そして、本発明は、この目的を達成するための手段として、請求項１に記載した、液状の被乾燥材料を、竪型チューブ１に供給してそれの内壁面１０に中空パイプ状に凍結させ、これを真空下において凍結乾燥させる凍結乾燥手段において、竪型チューブ１に対して供給する液材料を一時貯溜しておくタンクに、少なくとも第１タンクａと第２タンクｂとの２つ以上の複数を用意し、それらタンクａ・ｂを、竪型チューブ１の上方乃至内腔に配設するスプレーノズルｄに接続する給液ラインｃに対し交互に切り替わって連通するよう接続し、竪型チューブ１の下端側に接続する管路ｋには、竪型チューブ１内を流過する液材料を回収する回収ラインｅの上流側を接続連通し、その回収ラインｅの下流側を、前記第１・第２のタンクａ・ｂに対し交互に切り替わって連通するよう接続しておき、前記第１・第２のタンクａ・ｂの一方に液材料の所定量を注入して、その液材料を給液ラインｃを介しスプレーノズルｄに送給し、そのスプレーノズルｄにより竪型チューブ１の内壁面１０に対し散布してチューブ状の凍結層に凍結させ、未凍のまま流下する液材料を、竪型チューブ１の下端に接続する管路ｋの液溜部Ｌに集めて回収ラインｅにより他方のタンクに回収させ、一方のタンク内の液材料が空になったところで、第１・第２のタンクａ・ｂの給液ラインｃおよび回収ラインｅに対する接続を入れ換えて、スプレーノズルｄからの液材料のスプレーと未凍液の回収を行い、これの繰り返しにより、竪型チューブ１の内壁面に液材料を中空パイプ状に凍結させることを特徴とする凍結乾燥装置の竪型チューブの内壁面に対する液材料の凍結方法を提起するものである。
【００１４】
また、これに併せて、請求項２に記載した、外周を不凍熱媒流体が循環するジャケット囲い内壁面１０を液状の被乾燥材料の凍結面とするとともに凍結した被乾燥材料に対し昇華熱を供給する加熱面とする竪型チューブ１と、その竪型チューブ１の上方に接続する気密室１ａと、トラップｉを収蔵して前記気密室１ａに設けた真空引口ｆにバルブｈを介して接続するトラップ室ｇと、調整した液材料を貯溜させる少なくとも２つ以上のタンクａ・ｂと、竪型チューブ１の上方乃至内腔に配設する液材料スプレー用のスプレーノズルｄと、タンクａ・ｂ内の液材料をスプレーノズルｄに導く給液ラインｃと、スプレーノズルｄから散布されて竪型チューブ１内を流下する液材料の未凍部を回収して前記タンクａ・ｂに送給する回収ラインｅと、給液ラインｃをタンクａ・ｂに対し交互に接続する状態に切り替える切替バルブｖ１と、回収ラインｅをタンクａ・ｂに対し交互に接続す状態とに切り替える切替バルブｖ２と、からなり、切替バルブｖ１・ｖ２は、給液ラインｃを一方のタンクａに接続させたときに、回収ラインｅが他方のタンクｂと接続する状態となるように制御せしめてあることを特徴とする凍結乾燥装置を提起し、
【００１５】
さらに、請求項３に記載の、竪型チューブ１の上方の気密室１ａまたは竪型チューブ１の下端側の管路ｋに加圧空気を吐出するチューブ加圧弁ｖ１３を設けて、竪型チューブ１の内腔およびその下方に接続する管路ｋ内を加圧し、タンクａ・ｂにはベント弁ｖ１４を設けて、回収ラインｅに接続させた側のタンク内を大気に開放させ、竪型チューブ１内を流過して管路ｋに流下してくる未凍の液材料を、竪型チューブ１および管路ｋ内に与えるエアーの圧力により、回収ラインｅでタンクａ・ｂのうちの一方のタンクに向け圧送することを特徴とする請求項２記載の凍結乾燥装置、
【００１６】
および請求項４に記載の、竪型チューブ１の下端側に接続する管路ｋに、略水平な液溜部Ｌの上流側を接続して設け、その液溜部Ｌの下流側に回収ラインｅを接続したことを特徴とする請求項２または請求項３記載の凍結乾燥装置、
【００１７】
および請求項５に記載の、竪型チューブ１の下端側に接続する管路ｋに流下してくる未凍の液材料を竪型チューブ１内のエアーの圧力によりタンクａ・ｂのうちの一方のタンクに向け圧送する回収ラインｅを、大径の回収ラインｅ１と小径の回収ラインｅ２とに分け、竪型チューブ１内のエアーの圧力の低下により大径の回収ラインｅ１に設けたバルブｖ９を閉じて小径の回収ラインｅ２により未凍液を圧送させることを特徴とする請求項２または請求項３記載の凍結乾燥装置、
【００１８】
ならびに請求項６記載の、タンクａ・ｂ内に、側枝状のエアー吐出管９１を設けた泡立ち防止管９を配設し、それのタンクａ・ｂから上方に突出する上端側に回収ラインｅの下流側を接続せしめることを特徴とする請求項２または請求項３記載の凍結乾燥装置を提起するものである。
【００１９】
【発明の実施の形態】
次に本発明手段の実施の態様を、図面に随い実施例について説明する。
図３は本発明手段を実施せる凍結乾燥装置の全体の展開図で、同図において、１は、内壁面１０に液材料を中空のパイプ状に凍結させる竪型チューブ、１ａは竪型チューブ１の上方に接続する気密室、ａはその竪型チューブ１に対して供給する液材料を一時貯溜させておく第１タンク、ｂはこれに並設しておく第２タンク、ｃは、第１タンクａおよび第２タンクｂから液材料を竪型チューブ１に導く給液ライン、ｄはその給液ラインｃで導かれれる液材料を竪型チューブ１内壁面に対しスプレーにより供給するよう竪型チューブ１内に配設したスプレーノズル、ｅはそのノズルｄから竪型チューブ１の内壁面に供給されて、凍結しきれずに流下する未凍液を回収する回収ライン、ｆは竪型チューブ１の内壁面１０への液材料の凍結行程が終えて、中空パイプ状に凍結した液材料の凍結層を、真空下において、昇華熱の供給により真空乾燥させるときに、昇華してくる水蒸気を引き出すよう気密室１ａに設けた真空引口、ｇはこの真空引口ｆにバルブｈを介して接続するトラップ室、ｉはトラップ室ｇ内に設けた水蒸気を捕集するトラップ、ｊは凍結層の乾燥行程を終えて、竪型チューブ１の下方に接続する管路ｋに落下させる乾燥した凍結層を粉砕する粉砕装置で、微粉砕器６０とサイクロン６１とバッグフィルタ６２とを具備する。
【００２０】
ｖ１は、給液ラインｃの、第１タンクａおよび第２タンクｂに対する接続状態を交互に切り替えるよう給液ラインｃに設けた切替バルブ、ｖ２は回収ラインｅの第１タンクａおよび第２タンクｂに対する接続を交互に切り替えるための切替バルブ、ｖ３は常時は閉弁状態に保持せしめておいて、乾燥行程を終えて乾燥した凍結層を粉砕処理するときに、竪型チューブ１の下方の管路ｋが粉砕装置ｊに連通するよう開弁状態に切り替わるバルブ、ｖ４は、常態において開弁状態に保持せしめておいて、乾燥し終えた液材料を竪型チューブ１内から落下させて粉砕処理するときに閉弁状態とするように回収ラインｅに設けておくバルブである。
【００２１】
竪型チューブ１は、ステンレスの金属材により軸線方向を鉛直方向としたシリンダ状に成形し、周囲を図４にあるように、熱媒流体を循環させるジャケット１２で囲い、そのジャケット１２内に循環させる熱媒流体の温度制御により、内壁面１０の温度が所望に制御されるようにしておく。
【００２２】
この竪型チューブ１の内壁面１０に凍結させる液材料の供給は、竪型チューブ１の上部乃至内腔に配設しておくスプレーノズルｄによる散布により行う。
【００２３】
このスプレーノズルｄは、液材料を竪型チューブ１の内壁面１０に凍結させる際、それに先立ち、内壁面１０に精製水を散布して薄い氷膜を形成し、その氷膜上に液材料を凍結させるようにする場合には、ｋの氷膜形成用に設けるスプレーノズルｄを用い、さらに、精製水の収容しておくタンクおよび給水ラインも、液材料を貯溜せしめておくタンクおよび給水ラインｃを共用するようにしてよい。
【００２４】
しかして、スプレーノズルｄは、図４に示す実施例においては、竪型チューブ１の上端側に拡径する拡径筒部状の気密室１ａを接続して、それの内腔の中心部位にスプレーノズルｄを配設し、かつ、この気密室１ａの筒壁の下端側を下降側に向け次第に縮径する傾斜壁１３に形成して、この傾斜壁１３の下端縁を竪型チューブ１の周壁の上端縁に連続させておき、スプレーノズルｄから散布される液材料が、この傾斜壁１３をつたって竪型チューブ１の内壁面１０およびその内壁面１０に凍結した液材料の凍結層の表面に流れ込むようにしている。
【００２５】
このスプレーノズルｄにより竪型チューブ１の内壁面１０に供給する液材料は、原材料から調整装置により調整して、竪型チューブ１内に中空パイプ状に凍結させるのに対応する所定量に計量し、これを、タンクに一時貯溜し、そのタンクからエアーの加圧による圧送で給液ラインｃを経てスプレーノズルｄに導き、そのスプレーノズルｄで散布するようにするが、その散布は、ジャケット１２内の熱媒流体により凍結温度に保持されている竪型チューブ１の内壁面１０乃至それの凍結した液材料の凍結層に接触したときに、凍結しきれないで流下していく未凍部分が生ずる程度の量として散布するようにする。
【００２６】
そして、この未凍のまま竪型チューブ１の内部を下方に流過する散布した液材料の未凍部分は、竪型チューブ１の下方に接続する管路ｋに形成する液溜まりに集め、そこから回収ラインｅを介してタンクに戻し、再び竪型チューブ１に対し供給するようにすることから、タンクには、給液ラインｃを介してスプレーノズルｄに液材料を供給するための供給用タンクとなる第１タンクａと、回収ラインｅを介して回収する液材料の未凍部を一時貯溜させるための回収タンクとなる第２タンクｂとの少なくとも２つのタンクを用意する。
【００２７】
そして、これら第１・第２のタンクａ・ｂは、それらを、給液ラインｃおよび回収ラインｅに対して、交互に切り替わって接続するよう切替バルブｖ１・ｖ２を介して接続しておき、第１タンクａに投入した液材料を、その第１タンクａから給液ラインｃを経てスプレーノズルｄに送給して竪型チューブ１に対し散布し、それにより未凍のまま竪型チューブ１内を流過する液材料の未凍部を、回収ラインｅを介して第２タンクｂに回収している状態において、第１タンクａ内に投入した液材料の液量が空になったときに、切替バルブｖ１・ｖ２を切り替えて、第１タンクａが回収ラインｅに接続し、第２タンクｂが給液ラインｃに接続する状態とし、これにより、第２タンクｂがそれに回収した未凍の液材料を給液ラインｃを経てスプレーノズルｄに送り出す供給タンクとなり、第１タンクａが未凍のまま竪型チューブ１内を流過する液材料を回収ラインｅを介し回収する回収タンクの役割を果たすようにし、さらに、この第２タンクｂ内の液材料の液量が空になったとき、再び切替バルブｖ１・ｖ２の切り替え作動で、第１タンクａと第２タンクｂの役割の入れ換えが行えるようにする。
【００２８】
このときの、第１タンクａおよび第２タンクｂ内の液材料の液量が空になったときの検出は、図５示している例の如く、第１・第２の各タンクａ・ｂの底部に接続する排出管７０・７０に、液量の有無を確認する液量センサｓ１・ｓ２を、それら排出管７０・７０の給液ラインｃに対する接続をオン・オフするドレン弁ｖ５・ｖ６の上流側に設けておいて、この液量センサｓ１・ｓ２の検出作動で行うようにしてよい。
【００２９】
この図５に示す実施例においては、第１タンクａの排出管７０に設けた液量センサｓ１が液量無しを検出したときに、その排出管７０に設けたドレン弁ｖ５が閉じて第２タンクｂの排出管７０に設けたドレン弁ｖ６を開として、給液ラインｃに第２タンクｂが接続し、同時に、第１タンクａの上部の給液管７１に設けた給液弁ｖ７およびベント弁ｖ１４が開き、第２タンクｂの上部の給液管７１に設けた給液弁ｖ８およびベント弁ｖ１４が閉となって、回収ラインｅが第１タンクａに接続する状態に切り替わり、また、第２タンクｂの排出管７０に設けた液量センサｓ２が液量無しを検出したときに、その排出管７０に設けたドレン弁ｖ６を閉じ、第１タンクａの排出管７０に設けたドレン弁ｖ５を開いて、給液ラインｃに第１タンクａが接続し、同時に、第２タンクｂの給液弁ｖ８およびベント弁ｖ１４が開き、第１タンクａの給液弁ｖ７およびベント弁ｖ１４が閉じて回収ラインｅが第２タンクｂに接続する状態に切り替わるように制御せしめている。
【００３０】
給液ラインｃを介してスプレーノズルｄからの散布により、竪型チューブ１の内壁面１０に対し液材料を供給したときに、未凍のまま竪型チューブ１内を流過する液材料の、回収ラインｅにより回収タンクとする第１・第２タンクａ・ｂの何れかへの回収は、この流過する未凍液を、竪型チューブ１の下端側に接続する管路ｋに適宜形成しておく液溜まりに集め、それを、エアーによる圧送またはポンプ装置によるポンプアップにより、回収ラインｅを介し回収タンクとする第１・第２タンクａ・ｂに送り上げるようにしてよいが、液材料が、ポンプ類の回転部分との接触を嫌う薬品である場合には、エアーの圧送により行うようにする。
【００３１】
この回収ラインｅにより第１・第２タンクａ・ｂに回収される未凍液は、前述した如く、竪型チューブの内壁面１０にスプレーノズルｄから液材料をスプレーして凍結させていく凍結行程の進行に伴い行う第１タンクａおよび第２タンクｂの、給液ラインｃおよび回収ラインｅへの接続を交互に切り替える度ごとに、次第にその量が減少してくる。
【００３２】
そして、その量が、エアーによる圧送、またはポンプアップによる揚送ができなくなるまで低下してきたときに、管路ｋおよび回収ラインｅに残る液材料は、第１・第２タンクａ・ｂの何れにも回収できないことで竪型チューブ１内に凍結させ得ないことから、廃棄する他はなく、これが損失となる。
【００３３】
この最後に管路ｋよび回収ラインｅに残る液材料の量を少なくするために、図６に示している実施例においては、管路ｋに接続させる回収ラインｅを、それぞれが、バルブｖ９・ｖ１０を介して管路ｋに接続する大径のラインｅ１と小径のラインｅ２とに分け、かつ、これらラインｅ１・ｅ２による液材料の揚送をエアーによる圧送で行うようにしておいて、竪型チューブ１内を流過してくる未凍液の量が多いときには、大径のラインｅ１と小径のラインｅ２のバルブｖ９・ｖ１０を開いて、両方のラインｅ１・ｅ２で未凍液を圧送し、未凍液の量が少なくなってきたときには、大径のラインｅ１のバルブｖ９を閉じて、小径のラインｅ２だけで未凍液の圧送を行うようにしておくことで、この小径のラインｅ２による液材料の圧送が不能となってきたときに残る未凍液の量を極く少なくし得るようにしている。
【００３４】
即ち、この実施例では、竪型チューブ１の下端部に、接続鍔８０を組み付けて、それの下面側に、凍結した液材料の凍結層を粗粉砕するためのジェットノズル８１を組み込んだノズル付きフランジ８２を接合して組み付け、これの下面側に、ロート状の受け８３を具備する管路ｋを接続して設け、その管路ｋの、チューブボトム弁ｖ１１を介して粉砕装置ｊに接続するエルボ状の屈曲部の終端で、前記チューブボトム弁ｖ１１の手前の位置に、竪型チューブ１の内腔を流過して管路ｋに流下してくる未凍液を排出する排出管８４を設けて、これに、略水平な液溜部Ｌを、常時は開放しておき凍結し終えた液材料を凍結乾燥する乾燥工程時に閉めておく底弁ｖ１２を介して接続し、この液溜部Ｌの下流側に、回収ラインｅの大径のラインｅ１と小径のラインｅ２とを、それぞれバルブｖ９・ｖ１０を介して接続しておき、流下してくる未凍液を、竪型チューブ１の上部側に接続しておくチューブ加圧弁ｖ１３により竪型チューブ１内に与えておくエアーの圧力で、この大径のラインｅ１および小径のラインｅ２に押し上げ、それらが接続するタンクに流入させるようにしている。
【００３５】
このとき、第１・第２の各タンクａ・ｂには、ベント弁ｖ１４を設けておき、回収ラインｅに接続させた側のタンクのベント弁ｖ１４を開放して、タンク内を大気に開放しておくことで、未凍液は、加圧弁ｖ１３から竪型チューブ１内に与えられている圧力と大気開放のタンク内の圧力との圧力差によりタンク内に押し上げられる。
【００３６】
このエアーによる未凍液の押し上げは、液溜管である液溜部Ｌ内に未凍液が満たされているときは、未凍液だけが、大径のラインｅ１および小径のラインｅ２を圧送されるようになるが、液量が少なくなってくると、エアーの一部が、未凍液を巻き込むように吹き上げられ、液を泡状にして押し上げていくようになり、同時に、竪型チューブ１内のエアーの圧力は低下してくる。
【００３７】
竪型チューブ１またはこれに接続する管路ｋの適宜位置に、この竪型チューブ１内または管路ｋ内の圧力を検出する圧力センサ（図示省略）を設けて、この圧力センサが、設定した一定の圧力以上の圧力を検出したときに、大径のラインｅ１のバルブｖ９を閉弁させるようにこの圧力センサによりバルブｖ９を制御させておき、これにより、液溜部の未凍液の量が少なくなってきたときは、小径のラインｅ２だけで液の押し上げを行わすようにし、これにより、液溜部に溜まる未凍液の量が増え、再び竪型チューブ１内の圧力が上昇してくれば、大径のラインｅ１のバルブｖ９が開弁し、大径のラインｅ１と小径のラインｅ２の両方で未凍液をタンクに押し上げていくようにし、この繰り返しで未凍液のタンクへの回収を行わせる。
【００３８】
これによって、このエアーの圧送による未凍液のタンクへの回収は、最終的には、小径のラインｅ２の上流側の部位に数ｃｃの未凍液を残すまで行われ、凍結させ得ないことで廃棄するようになる未凍液の量を極く少なくし得るようになる。
【００３９】
次に、図７は、上述の如く、未凍液を回収ラインｅでタンクａ・ｂに回収するのに、エアーの圧送により未凍液を回収ラインｅに押し上げていくようにしたとき、タンクａ・ｂに戻された未凍液に、エアーによる圧送の際に未凍液中に包含されるようになる気泡によって、泡立ちが生ずるようになるのを防止するための手段を示している。
【００４０】
同図において、９は、第１・第２の各タンクａ・ｂ内に挿し込んで、そのタンクａ・ｂ内の一隅に寄せた部位に配設した泡立ち防止管で、タンクの上部から上方に突出する上端側は、未凍液の回収ラインｅの下流側に接続連通し、下端側は、それの開口９０を、タンクａ・ｂのロート状をなす底部の傾斜壁７２の内壁面と平行して対向するようにし、かつ、管壁には、タンクａ・ｂの内壁面に向けて、側枝管状に突出するエアーの吐出管９１…を上下に多段に並列させて設け、それら各吐出管９１の開口９１０…を、タンクａ・ｂの機壁７３の内壁面に接近する位置に開放させてある。
【００４１】
これにより、回収ラインｅをエアーの圧送によって揚送されてくる未凍液は、タンクａ・ｂ内に放流されるときに、この泡立ち防止管９を経て、それの下端の開口９０からタンクａ・ｂの底部の傾斜壁７２に当たるように放出されることで、タンクａ・ｂ内の未凍液に衝激を与えることなく放流され、また、未凍液中に含まれる気泡が、泡立ち防止管９内を流下する未凍液から分離して、側枝状に設けたエアーの吐出管９１…から吐出するようになり、未凍液中のエアーを逃すようになるので、タンクａ・ｂ内に回収した未凍液に泡立ちが生ずるようになるのを防止し得るようになる。
【００４２】
このように本発明手段は、竪型チューブ１の内壁面１０に液状の被乾燥材料を中空パイプ状に凍結させて、それを真空下において凍結乾燥させる凍結乾燥手段において、竪型チューブ１の内壁面１０に液材料を中空パイプ状に凍結させるのに、液材料の竪型チューブ１に対する供給は、調整そしてタンクに収蔵せしめた液材料を、給液ラインｃにより竪型チューブ１の上方乃至内腔に配設したスプレーノズルｄに導いて、そのスプレーノズルｄよりの散布により行って、竪型チューブ１の内壁面１０に凍結しきれない未凍液が流下していくようにする。
【００４３】
そして、液材料を貯溜せしめるタンクは少なくとも２つ以上を用意しておいて、未凍のまま竪型チューブ１内を流過する液材料を回収ラインｅにより別のタンクに回収していき、液材料を収蔵せしめたタンクが空になったときに、給液ラインｃと回収ラインｅのタンクに対する接続を入れ換えて、未凍液を回収したタンクからその未凍液をスプレーノズルｄに供給し、竪型チューブ１内を流下する未凍液を空になったタンクに回収し、これを繰り返すことで、竪型チューブ１の内壁面に液材料を中パイプ状に凍結させるようにすることから、タンクに収蔵せしめる液材料の量を竪型チューブ１の内壁面１０に中空パイプ状に凍結させる量と対応させておくことで、凍結を終えたときに抜き出す未凍液の量を著しく少なくし得るようになる。
【００４４】
【発明の効果】
以上説明したように本発明手段によれば、竪型チューブ１の内壁面１０に液材料を中空パイプ状に凍結させるのが、所定の厚さの凍結層に凍結させたときに抜き出して廃棄するようになる未凍液の量を少なくし得る。
【図面の簡単な説明】
【図１】従前の凍結乾燥装置の縦断面図である。
【図２】同上の部分の横断面図である。
【図３】本発明手段を実施せる凍結乾燥装置の全体の概要展開図である。
【図４】同上の竪型チューブ部分の一部破断した正面図である。
【図５】同上のタンク部分の一部破断した正面図である。
【図６】同上の別の実施例の要部の一部破断した正面図である。
【図７】同上のさらに別の実施例のタンクの一部破断した正面図である。
【符号の説明】
Ａ…真空凍結乾燥装置、ａ…第１タンク、ｂ…第２タンク、ｃ…給液ライン、ｄ…スプレーノズル、ｅ…回収ライン、ｅ１…大径の回収ライン、ｅ２…小径の回収ライン、ｆ…真空引口、ｇ…トラップ室、ｈ…バルブ、ｉ…トラップ、ｊ…粉砕装置、ｋ…管路、Ｌ…貯溜部、ｓ１・ｓ２…液量センサ、ｖ１・ｖ２…切替バルブ、ｖ３・ｖ４…バルブ、ｖ５・ｖ６…ドレン弁、ｖ７・ｖ８…給液弁、ｖ９ｖ・ｖ１０…バルブ、ｖ１１…チューブボトム弁、ｖ１２…底弁、ｖ１３…チューブ加圧弁、ｖ１４…ベント弁、１…竪型チューブ、１ａ…気密室、１０…内壁面、１１…供給管、１２…ジャケット、１３…傾斜壁、２…竪型筒状体、２０…筒壁、２１…ブラインノズル、２２…排出管、３…トラップ室、３０…トラップ（蒸気凝結器）、４…機壁、５…扉、５０…ヒンジ、５１…流路、６０…微粉砕器、６１…サイクロン、６２…バッグフィルタ、７…排出管、７１…給液管、７２…傾斜壁、７３…機壁、８０…接続鍔、８１…ジェットノズル、８２…フランジ、８３…ロート状の受け、８４…排出管、９…泡立ち防止管、９０…開口、９１…エアー吐出管、９１０…開口。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method in which a liquid material to be dried such as a chemical solution prepared from a raw material is frozen to a predetermined thickness on an inner wall surface of a vertical tube whose outer peripheral surface can be heated and cooled by an antifreezing heat medium fluid. The present invention relates to a freeze-drying means for freezing a frozen layer into a layer and freeze-drying the frozen layer by supplying sublimation heat under vacuum, wherein the freeze-drying means freezes a liquid material to be dried as a frozen layer on the inner wall surface of a tube.
[0002]
[Prior art]
In the freeze-drying means for freezing the liquid material to be dried as a frozen layer on the inner wall surface of the tube in the vertical direction and freeze-drying it under vacuum, the freezing of the liquid material to be dried on the inner wall surface of the tube is conventionally performed. For example, this is performed by means disclosed in Japanese Patent Publication No. 6-35911.
[0003]
In this means, as shown in FIGS. 1 and 2, a cooling surface also serving as a heating surface for supplying heat to the material to be freeze-dried is constituted by the inner wall surface 10 of the vertical tube 1 and a drying chamber for accommodating the same. Is formed by the cylindrical wall 20 of the vertical cylindrical body 2, and a trap (steam condenser) that collects water vapor to be sublimated from the material to be dried frozen on the inner wall surface 10 of the vertical tube 1 and keeps the vacuum. 30 is disposed on the outer periphery of the cylindrical wall 20 of the vertical cylindrical body 2 forming the drying chamber, and the outer periphery of the trap 30 is surrounded by the outer cylindrical machine wall 4. A trap chamber 3 is formed between the cylindrical wall 20 of the vertical cylindrical body 2 forming the partition of the chamber and the inner peripheral surface of the cylindrical wall 20 of the vertical cylindrical body 2 and the outer periphery of the vertical tube 1. By circulating an antifreeze heat medium fluid in the space between the inner and outer surfaces, the cooling surface of the inner wall surface 10 of the vertical tube 1 can be heated and cooled. As constitute the dried material to a vacuum freeze-drying apparatus A forms be lyophilized under vacuum to freeze on the inner wall surface 10 of Tategata tube 1.
[0004]
In order to freeze the material to be dried on the inner peripheral surface 10 of the vertical tube 1 as a frozen layer, the opening on the bottom side of the vertical tube 1 is opened and closed around the hinge 50 as shown in FIG. A flow path 51 of the material to be dried, which has been adjusted to a liquid state, is formed between the upper surface side of the rotating door 5 and communicated with the flow path 51. The material to be dried is supplied and pushed up into the inner cavity of the vertical tube 1, and when the level thereof is near the opening on the upper end side of the vertical tube 1, the supply of the material to be dried is stopped.
[0005]
In this state, circulation of the antifreeze heat medium fluid which is fed from the brine nozzle 21 and discharged from the discharge pipe 22 is provided between the inner peripheral surface 20 of the vertical cylindrical body 2 and the outer peripheral surface of the vertical tube 1. By cooling, the liquid material to be dried is frozen on the inner wall surface 10 of the vertical tube 1.
[0006]
When the thickness of the frozen layer of the material to be dried frozen on the inner wall surface of the vertical tube 1 reaches a predetermined thickness, the freezing process is stopped, and the unfreezed material to be dried is extracted from the supply pipe 11. The freezing process is terminated so that a frozen layer having a predetermined thickness remains in the shape of a hollow pipe in the vertical tube 1.
[0007]
Next, the process is shifted to a drying step, in which the water vapor is sublimated and dried from the inner surface of the material to be dried frozen in the frozen layer in the shape of a hollow pipe.
[0008]
[Problems to be solved by the invention]
The above-described liquid material to be dried is pushed into the vertical tube 1 to a predetermined level so as to be pushed up, and is frozen on the inner wall surface 10 of the vertical tube 1 so that the frozen layer has a predetermined thickness. When the freezing liquid is dropped, the means for freezing the liquid material in the form of a hollow pipe on the inner wall surface 10 of the vertical tube 1 requires a considerable amount of unfreezing liquid to be extracted when the liquid material is frozen. Therefore, there is a problem that the loss due to the unfrozen liquid that is extracted and discarded is large.
[0009]
The ratio of the amount of unfrozen liquid extracted after freezing this liquid material to the inner surface of the vertical tube 1 with respect to the amount of the liquid material supplied into the vertical tube 1 is such that the vertical tube 1 has a diameter of 85 mm. If the liquid material is frozen to a thickness of more than ten millimeters, the amount is almost two thirds.
[0010]
The amount of the unfrozen liquid to be withdrawn can be reduced by increasing the thickness of the frozen layer of the liquid material to be frozen on the inner peripheral surface of the vertical tube 1. The hollow pipe shape is used to make the inner peripheral surface of the hollow pipe a sublimation surface of water vapor during the drying process. Sublimation from the frozen layer is performed efficiently and uniformly from each part of the frozen layer. In order to allow the freezing layer to be frozen, the diameter of the center hole of the frozen layer of the liquid material to be frozen on the inner wall surface 10 of the vertical tube 1 in the form of a hollow pipe must be sufficiently large with respect to the thickness of the frozen layer. The amount of the unfrozen liquid extracted after freezing the liquid material becomes a considerable amount with respect to the total amount of the liquid material supplied into the vertical tube 1.
[0011]
Vacuum drying devices are arranged side by side in multiple units, and by supplying the unfrozen liquid extracted by the first device to the second device, loss is prevented, but the last The unfrozen liquid extracted in the apparatus cannot be used because there is no vertical tube 1 to be frozen. When the storage period is limited due to the quality change after the liquid material is adjusted to a liquid material, such as a chemical solution, there is no other choice but to discard the product. However, there is a big problem in reducing the amount of the unfrozen liquid that cannot be frozen and must be discarded.
[0012]
The present invention has been made to solve this problem, in which a liquid material is frozen in the form of a hollow pipe on the inner wall surface of a vertical tube, and the liquid material is frozen by supplying sublimation heat under vacuum. In the freeze-drying means for drying, the liquid material supplied into the tube is frozen in the form of a hollow pipe on the inner wall surface of the tube, so that the amount of unfrozen liquid left unfrozen at the end of the freezing process is extremely small. It is an object of the present invention to provide means for reducing the number of operations.
[0013]
[Means for Solving the Problems]
In the present invention, as a means for achieving this object, the liquid material to be dried described in claim 1 is supplied to the vertical tube 1 and frozen on the inner wall surface 10 thereof into a hollow pipe shape. In a freeze-drying means for freeze-drying the liquid material under vacuum, at least two tanks of a first tank a and a second tank b are provided in a tank for temporarily storing a liquid material to be supplied to the vertical tube 1. A plurality of tanks a and b are prepared so that the tanks a and b are alternately connected to and connected to a liquid supply line c connected to a spray nozzle d disposed above or in the lumen of the vertical tube 1. A pipe k connected to the lower end of the first tube 1 is connected to an upstream side of a recovery line e for recovering the liquid material flowing through the vertical tube 1, and a downstream side of the recovery line e is connected to the first line.・ For the second tank a ・ b The connection is made alternately so as to communicate with each other, a predetermined amount of the liquid material is injected into one of the first and second tanks a and b, and the liquid material is supplied to the spray nozzle d via the liquid supply line c. The liquid material is sprayed onto the inner wall surface 10 of the vertical tube 1 by the spray nozzle d to freeze the tube into a frozen layer, and the liquid material flowing down unfrozen is connected to the lower end of the vertical tube 1. The liquid is collected in the liquid reservoir L of the pipe k and collected in the other tank by the collection line e. When the liquid material in one tank becomes empty, the liquid supply lines of the first and second tanks a and b are used. The liquid material is sprayed from the spray nozzle d and the unfrozen liquid is recovered by exchanging the connection between the liquid material c and the recovery line e, and the liquid material is frozen into a hollow pipe shape on the inner wall surface of the vertical tube 1 by repeating these steps. Freezing characterized by Freezing method of the liquid material to the inner wall surface of the vertical tube of the drying apparatus is to raise.
[0014]
In addition, the inner wall surface 10 of the jacket around which the antifreeze heat medium fluid circulates is used as a freezing surface of the liquid material to be dried, and the sublimation heat is applied to the frozen material to be dried. Via a valve h to a vertical tube 1 serving as a heating surface for supplying air, an airtight chamber 1a connected above the vertical tube 1, and a vacuum port f provided in the airtight chamber 1a for storing a trap i. Chamber g, at least two tanks a and b for storing the adjusted liquid material, a spray nozzle d for spraying the liquid material disposed above or inside the vertical tube 1, and a tank. a liquid supply line c for introducing the liquid material in a and b to the spray nozzle d; and an unfrozen portion of the liquid material sprayed from the spray nozzle d and flowing down the vertical tube 1 and collected in the tanks a and b. A collection line e for feeding; A switching valve v1 for switching between a state in which the liquid line c is alternately connected to the tanks a and b, and a switching valve v2 for switching between a state in which the recovery line e is alternately connected to the tanks a and b. v1 · v2 is a freeze-drying apparatus characterized in that when the liquid supply line c is connected to one tank a, the recovery line e is connected to the other tank b. Raised,
[0015]
Furthermore, a tube pressurizing valve v13 for discharging pressurized air is provided in the airtight chamber 1a above the vertical tube 1 or the pipe k on the lower end side of the vertical tube 1 according to claim 3, and the vertical tube 1 Is pressurized, and a vent valve v14 is provided in the tanks a and b to open the inside of the tank connected to the recovery line e to the atmosphere. One of the tanks a and b is collected in the recovery line e by the pressure of the air supplied to the vertical tube 1 and the pipe k. The freeze-drying apparatus according to claim 2, wherein the freeze-drying apparatus feeds the liquid to a tank.
[0016]
And a pipe k connected to the lower end side of the vertical tube 1 according to claim 4, wherein an upstream side of the substantially horizontal liquid reservoir L is connected and provided, and a collection line is provided downstream of the liquid reservoir L. The freeze-drying apparatus according to claim 2 or 3, wherein e is connected.
[0017]
An unfrozen liquid material flowing down to a pipe k connected to the lower end of the vertical tube 1 according to claim 5, wherein one of the tanks a and b is pressed by the pressure of the air in the vertical tube 1. The collection line e for pressure feeding to the tank is divided into a large-diameter collection line e1 and a small-diameter collection line e2, and a valve v9 provided in the large-diameter collection line e1 due to a decrease in the pressure of the air in the vertical tube 1. The freeze-drying apparatus according to claim 2 or 3, wherein the non-freezing solution is pumped through a small-diameter recovery line e2.
[0018]
And a bubbling prevention pipe 9 provided with a side-branch air discharge pipe 91 in the tanks a and b according to claim 6, and a recovery line e at an upper end protruding upward from the tanks a and b. A freeze-drying apparatus according to claim 2 or 3, wherein a downstream side of the freeze-drying apparatus is connected.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 3 is an overall development view of a freeze-drying apparatus for carrying out the means of the present invention. In the figure, reference numeral 1 denotes a vertical tube for freezing a liquid material into a hollow pipe on an inner wall surface 10; A is a first tank for temporarily storing a liquid material to be supplied to the vertical tube 1, b is a second tank arranged side by side with this, and c is a first tank. A liquid supply line for guiding the liquid material from the tank a and the second tank b to the vertical tube 1, and a vertical line d for supplying the liquid material guided by the liquid supply line c to the inner wall surface of the vertical tube 1 by spraying. A spray nozzle e disposed in the tube 1 is a collection line for collecting unfrozen liquid which is supplied from the nozzle d to the inner wall surface of the vertical tube 1 and flows down without being completely frozen. The freezing process of the liquid material on the inner wall surface 10 is completed. When the frozen layer of the liquid material frozen in the shape of a hollow pipe is vacuum-dried under vacuum by supplying sublimation heat, a vacuum port provided in the hermetic chamber 1a to extract the sublimated water vapor, g A trap chamber connected to a vacuum port f via a valve h, i is a trap for collecting water vapor provided in a trap chamber g, j is connected below the vertical tube 1 after the drying process of the frozen layer is completed. A pulverizing device for pulverizing a dried frozen layer dropped into a pipeline k, which is provided with a pulverizer 60, a cyclone 61, and a bag filter 62.
[0020]
v1 is a switching valve provided in the liquid supply line c so as to alternately switch the connection state of the liquid supply line c to the first tank a and the second tank b, and v2 is a first tank a and a second tank of the collection line e. The switching valve for alternately switching the connection to b, v3 is normally kept closed, and when the drying process is finished and the dried frozen layer is pulverized, the lower tube of the vertical tube 1 The valve v4, which is switched to the open state so that the path k communicates with the crushing device j, is kept open in the normal state, and the dried liquid material is dropped from the vertical tube 1 to perform the crushing process. This is a valve provided on the collection line e so that the valve is closed when the operation is performed.
[0021]
The vertical tube 1 is formed of a stainless steel metal material into a cylindrical shape with the axial direction being vertical, and the periphery thereof is surrounded by a jacket 12 for circulating a heat medium fluid as shown in FIG. The temperature of the inner wall surface 10 is controlled as desired by controlling the temperature of the heat medium fluid to be controlled.
[0022]
The supply of the liquid material to be frozen on the inner wall surface 10 of the vertical tube 1 is performed by spraying with a spray nozzle d disposed in the upper part or the inner cavity of the vertical tube 1.
[0023]
When the liquid material is frozen on the inner wall surface 10 of the vertical tube 1, the spray nozzle d sprays purified water on the inner wall surface 10 to form a thin ice film before the liquid material is frozen. In the case of freezing, a spray nozzle d provided for forming an ice film of k is used, and a tank and a water supply line for storing purified water are also used as a tank and a water supply line c for storing a liquid material. May be shared.
[0024]
In the embodiment shown in FIG. 4, the spray nozzle d is connected to an air-tight chamber 1a in the form of a large-diameter tube which expands in diameter at the upper end side of the vertical tube 1, and is provided at the center of the inner cavity thereof. A spray nozzle d is provided, and the lower end of the cylindrical wall of the hermetic chamber 1a is formed on an inclined wall 13 whose diameter gradually decreases toward the descending side. The liquid material sprayed from the spray nozzle d is made continuous with the upper edge of the peripheral wall, and the liquid material sprayed from the spray nozzle d passes through the inclined wall 13 to form an inner wall surface 10 of the vertical tube 1 and a frozen layer of the liquid material frozen on the inner wall surface 10. It flows into the surface.
[0025]
The liquid material supplied to the inner wall surface 10 of the vertical tube 1 by the spray nozzle d is adjusted from a raw material by an adjusting device, and is measured in a predetermined amount corresponding to freezing into a hollow pipe shape in the vertical tube 1. Is temporarily stored in a tank, and is sent from the tank to the spray nozzle d through the liquid supply line c by pressure feeding by pressurizing air, and is sprayed by the spray nozzle d. When it comes into contact with the inner wall surface 10 of the vertical tube 1 or the frozen layer of the frozen liquid material on the inner wall surface 10 of the vertical tube 1 kept at the freezing temperature by the heat medium fluid inside, the unfrozen portion that flows down without being completely frozen is formed. Spray as much as will occur.
[0026]
The unfrozen portion of the scattered liquid material flowing down the inside of the vertical tube 1 while being unfrozen is collected in a liquid reservoir formed in a pipe k connected below the vertical tube 1 and there. To the tank via the recovery line e, and supply the liquid to the vertical tube 1 again. Therefore, the tank is provided with a supply for supplying the liquid material to the spray nozzle d via the liquid supply line c. At least two tanks are prepared, a first tank a serving as a tank and a second tank b serving as a recovery tank for temporarily storing an unfrozen portion of a liquid material to be recovered via a recovery line e.
[0027]
The first and second tanks a and b are connected to the liquid supply line c and the recovery line e via switching valves v1 and v2 so as to be alternately connected. The liquid material charged into the first tank a is supplied from the first tank a to the spray nozzle d via the liquid supply line c and is sprayed on the vertical tube 1, whereby the vertical tube 1 is kept unfrozen. In the state where the unfrozen portion of the liquid material flowing through the inside is collected in the second tank b via the collection line e, when the liquid amount of the liquid material charged into the first tank a becomes empty. Then, the switching valves v1 and v2 are switched so that the first tank a is connected to the collection line e and the second tank b is connected to the liquid supply line c. Spray the frozen liquid material through the supply line c. The first tank a serves as a collection tank for collecting the liquid material flowing through the vertical tube 1 through the collection line e while the first tank a is not frozen. When the liquid amount of the liquid material in the tank b becomes empty, the roles of the first tank a and the second tank b can be switched by switching the switching valves v1 and v2 again.
[0028]
At this time, when the liquid amount of the liquid material in the first tank a and the second tank b becomes empty, the first and second tanks a and b are detected as in the example shown in FIG. Discharge pipes 70, 70 connected to the bottoms of the tanks are provided with liquid quantity sensors s1, s2 for checking the presence or absence of a liquid quantity, and drain valves v5, v6 for turning on and off the connection of the discharge pipes 70, 70 to the liquid supply line c. May be provided on the upstream side, and the detection may be performed by the detection operations of the liquid amount sensors s1 and s2.
[0029]
In the embodiment shown in FIG. 5, when the liquid amount sensor s1 provided in the discharge pipe 70 of the first tank a detects that there is no liquid amount, the drain valve v5 provided in the discharge pipe 70 is closed and the second valve is closed. The drain valve v6 provided in the discharge pipe 70 of the tank b is opened, the second tank b is connected to the liquid supply line c, and at the same time, the liquid supply valve v7 provided in the liquid supply pipe 71 above the first tank a and The vent valve v14 is opened, the liquid supply valve v8 and the vent valve v14 provided in the liquid supply pipe 71 above the second tank b are closed, and the state is switched to a state in which the collection line e is connected to the first tank a. When the liquid amount sensor s2 provided in the discharge pipe 70 of the second tank b detects that there is no liquid amount, the drain valve v6 provided in the discharge pipe 70 is closed, and the drain valve v6 provided in the discharge pipe 70 of the first tank a is provided. Open the drain valve v5 and connect the first tank a to the liquid supply line c. At the same time, the liquid supply valve v8 and the vent valve v14 of the second tank b are opened, the liquid supply valve v7 and the vent valve v14 of the first tank a are closed, and the state is switched to a state where the collection line e is connected to the second tank b. Control.
[0030]
When the liquid material is supplied to the inner wall surface 10 of the vertical tube 1 by spraying from the spray nozzle d through the liquid supply line c, the liquid material flowing through the vertical tube 1 without being frozen is The collection into the first and second tanks a and b as the collection tanks by the collection line e is performed by appropriately forming the flowing freezing liquid in a pipe k connected to the lower end of the vertical tube 1. The liquid may be collected in a liquid pool to be stored and pumped up by air or pumped up by a pump device to be pumped up to first and second tanks a and b as recovery tanks through a recovery line e. If the material is a chemical that does not like contact with the rotating parts of the pumps, the pumping is performed by air.
[0031]
As described above, the unfrozen liquid recovered in the first and second tanks a and b by the recovery line e is sprayed on the inner wall surface 10 of the vertical tube from the spray nozzle d to freeze the liquid material. Each time the connection of the first tank a and the second tank b to the liquid supply line c and the collection line e is alternately performed with the progress of the stroke, the amount gradually decreases.
[0032]
Then, when the amount has decreased to the point where it is no longer possible to perform pressure feeding by air or pumping up by pump-up, the liquid material remaining in the pipeline k and the recovery line e is either of the first and second tanks a and b. Since it cannot be frozen in the vertical tube 1 because it cannot be recovered, there is no alternative but to discard it, which is a loss.
[0033]
In order to reduce the amount of liquid material remaining in the pipe k and the recovery line e at the end, in the embodiment shown in FIG. 6, the recovery line e connected to the pipe k is connected to each of the valves v9 and v9. It is divided into a large-diameter line e1 and a small-diameter line e2 connected to the pipeline k via v10, and the pumping of the liquid material by these lines e1 and e2 is performed by air-pumping. When the amount of the antifreeze flowing through the mold tube 1 is large, the valves v9 and v10 of the large-diameter line e1 and the small-diameter line e2 are opened, and the antifreeze is pumped through both the lines e1 and e2. Then, when the amount of the antifreeze liquid has become small, the valve v9 of the large-diameter line e1 is closed, and the antifreeze liquid is pumped only by the small-diameter line e2, thereby making this small-diameter line e1. It is impossible to pump liquid material by e2 So that very capable of reducing the amount of non-freeze liquid which remains when came I.
[0034]
That is, in this embodiment, a connecting flange 80 is attached to the lower end of the vertical tube 1, and a jet nozzle 81 for coarsely crushing a frozen layer of the frozen liquid material is provided on the lower surface thereof. A flange 82 is joined and assembled, and a pipe k including a funnel-shaped receiver 83 is connected and provided on the lower surface side of the flange 82, and the pipe k is connected to a pulverizer j via a tube bottom valve v11. At the end of the elbow-shaped bent portion, at a position just before the tube bottom valve v11, there is provided a discharge pipe 84 for discharging the non-freezing liquid flowing down the lumen of the vertical tube 1 and flowing down the pipe k. A substantially horizontal liquid reservoir L is connected to this through a bottom valve v12 which is normally opened and closed at the time of a drying step of freeze-drying the frozen liquid material. Downstream of L, a large-diameter line e1 of the recovery line e The line e2 of diameter is connected via valves v9 and v10, respectively, and the flowing down antifreeze liquid is supplied to the vertical tube 1 by a tube pressurizing valve v13 connected to the upper side of the vertical tube 1. The pressure of the air supplied inside pushes up the large-diameter line e1 and the small-diameter line e2 so that they flow into the tank to which they are connected.
[0035]
At this time, a vent valve v14 is provided in each of the first and second tanks a and b, and the vent valve v14 of the tank connected to the collection line e is opened to open the tank to the atmosphere. By doing so, the antifreeze liquid is pushed up into the tank by the pressure difference between the pressure applied from the pressurizing valve v13 into the vertical tube 1 and the pressure in the tank that is open to the atmosphere.
[0036]
When the non-freezing liquid is filled in the liquid reservoir L, which is a liquid storage tube, only the non-freezing liquid pumps the large-diameter line e1 and the small-diameter line e2. However, when the liquid volume decreases, a part of the air is blown up so as to entrain the unfrozen liquid, and the liquid becomes foamy and pushes up. The pressure of the air in 1 decreases.
[0037]
A pressure sensor (not shown) for detecting the pressure in the vertical tube 1 or the pipe k is provided at an appropriate position of the vertical tube 1 or a pipe k connected thereto, and the pressure sensor is set. When a pressure equal to or higher than a certain pressure is detected, the valve v9 is controlled by the pressure sensor so that the valve v9 of the large-diameter line e1 is closed. When the amount of water has decreased, the liquid is pushed up only by the small-diameter line e2, whereby the amount of unfrozen liquid stored in the liquid reservoir increases, and the pressure in the vertical tube 1 increases again. Then, the valve v9 of the large-diameter line e1 is opened, and the antifreeze is pushed up to the tank in both the large-diameter line e1 and the small-diameter line e2. To be collected.
[0038]
As a result, the recovery of the unfrozen liquid into the tank by the compressed air is performed until a few cc of the unfrozen liquid is left in the upstream portion of the small-diameter line e2. The amount of unfrozen liquid to be discarded at the time can be extremely reduced.
[0039]
Next, FIG. 7 shows that, as described above, when the unfrozen liquid is collected in the tanks a and b by the collection line e, the unfrozen liquid is pushed up to the collection line e by the air supply. A means for preventing foaming from being generated by bubbles included in the antifreeze liquid when the antifreeze liquid returned to a and b is pumped by air is shown.
[0040]
In the figure, reference numeral 9 denotes an anti-foaming tube which is inserted into each of the first and second tanks a and b and is disposed at a position near one corner in the tanks a and b. The upper end protruding from the lower end is connected to the downstream side of the unfrozen liquid recovery line e, and the lower end is connected to the inner wall surface of the funnel-shaped bottom inclined wall 72 of the tanks a and b. Air discharge pipes 91 projecting in the form of side branch pipes are provided in parallel on the pipe wall so as to face the inner wall surfaces of the tanks a and b, and are provided in parallel in the upper and lower stages. The openings 910 of the pipes 91 are opened at positions near the inner wall surfaces of the machine walls 73 of the tanks a and b.
[0041]
As a result, when the unfrozen liquid pumped out of the collection line e by air pressure is discharged into the tanks a and b, the antifreeze liquid passes through the bubbling prevention pipe 9 and from the opening 90 at the lower end thereof to the tank a. -By being discharged so as to hit the inclined wall 72 at the bottom of b, the antifreeze in the tanks a and b is discharged without giving an impact, and bubbles contained in the antifreeze are prevented from foaming. The air is separated from the unfrozen liquid flowing down the pipe 9 and is discharged from the air discharge pipes 91 provided in a side branch shape, so that the air in the unfrozen liquid escapes. Bubbling of the unfrozen liquid collected at the same time can be prevented.
[0042]
Thus, the means of the present invention is a freeze-drying means for freezing the material to be dried in the form of a hollow pipe on the inner wall surface 10 of the vertical tube 1 and freeze-drying it under vacuum. In order to freeze the liquid material on the wall 10 in a hollow pipe shape, the supply of the liquid material to the vertical tube 1 is adjusted and stored in the tank. The liquid is guided to the spray nozzle d disposed in the cavity, and spraying is performed from the spray nozzle d so that the unfrozen liquid that cannot be completely frozen flows down to the inner wall surface 10 of the vertical tube 1.
[0043]
Then, at least two or more tanks for storing the liquid material are prepared, and the liquid material flowing through the vertical tube 1 without being frozen is collected in another tank by the collection line e. When the tank storing the material is emptied, the connection between the liquid supply line c and the recovery line e to the tank is exchanged, and the unfrozen liquid is supplied from the tank where the unfrozen liquid is recovered to the spray nozzle d, The unfrozen liquid flowing down the vertical tube 1 is collected in an empty tank, and this operation is repeated to freeze the liquid material on the inner wall surface of the vertical tube 1 in a medium pipe shape. By setting the amount of the liquid material to be stored in the tank to correspond to the amount to be frozen in the shape of a hollow pipe on the inner wall surface 10 of the vertical tube 1, the amount of the unfrozen liquid withdrawn when the freezing is completed can be significantly reduced. Become like
[0044]
【The invention's effect】
As described above, according to the present invention, the liquid material is frozen in the form of a hollow pipe on the inner wall surface 10 of the vertical tube 1, but when the frozen material is frozen into a frozen layer having a predetermined thickness, it is extracted and discarded. The amount of unfrozen liquid that may develop can be reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a conventional freeze-drying apparatus.
FIG. 2 is a cross-sectional view of the same part.
FIG. 3 is a schematic development view of the whole freeze-drying apparatus for implementing the means of the present invention.
FIG. 4 is a partially cutaway front view of the vertical tube portion of the above.
FIG. 5 is a partially cutaway front view of the same tank part.
FIG. 6 is a partially broken front view of a main part of another embodiment of the above.
FIG. 7 is a partially cutaway front view of a tank of still another embodiment of the above.
[Explanation of symbols]
A: vacuum freeze-drying device, a: first tank, b: second tank, c: liquid supply line, d: spray nozzle, e: collection line, e1: large-diameter collection line, e2: small-diameter collection line, f: vacuum port, g: trap chamber, h: valve, i: trap, j: crusher, k: pipeline, L: reservoir, s1, s2: liquid amount sensor, v1, v2: switching valve, v3 · V4: valve, v5, v6: drain valve, v7, v8: liquid supply valve, v9 v, v10: valve, v11: tube bottom valve, v12: bottom valve, v13: tube pressurizing valve, v14: vent valve, 1 ... Vertical tube, 1a ... airtight chamber, 10 ... inner wall surface, 11 ... supply pipe, 12 ... jacket, 13 ... inclined wall, 2 ... vertical cylindrical body, 20 ... cylinder wall, 21 ... brine nozzle, 22 ... discharge pipe 3, trap chamber, 30 trap (steam condenser), 4 Machine wall, 5 door, 50 hinge, 51 flow path, 60 pulverizer, 61 cyclone, 62 bag filter, 7 discharge pipe, 71 liquid supply pipe, 72 inclined wall, 73 machine Walls, 80: Connection flange, 81: Jet nozzle, 82: Flange, 83: Funnel-shaped receiver, 84: Discharge pipe, 9: Foaming prevention pipe, 90: Opening, 91: Air discharge pipe, 910: Opening.

Claims

The liquid material to be dried is supplied to the vertical tube 1 by a freeze-drying unit that supplies the material to the vertical tube 1 and freezes the inner wall surface 10 of the material in a hollow pipe shape, and freeze-drys the material under vacuum. At least two tanks, a first tank a and a second tank b, are prepared in a tank for temporarily storing the liquid material, and these tanks a and b are arranged above or in the inner cavity of the vertical tube 1. A liquid flowing through the vertical tube 1 is connected to a line k connected to a lower end of the vertical tube 1 by being connected alternately to a liquid supply line c connected to a spray nozzle d to be provided. The upstream side of the recovery line e for recovering the material is connected and connected, and the downstream side of the recovery line e is connected to the first and second tanks a and b so as to be alternately connected and communicate with each other. First and second tanks a and b A predetermined amount of the liquid material is injected into one side, and the liquid material is fed to the spray nozzle d via the liquid supply line c, and is sprayed on the inner wall surface 10 of the vertical tube 1 by the spray nozzle d to form a tube. The liquid material which has been frozen in the frozen layer and flows down without being frozen is collected in the liquid reservoir L of the pipe k connected to the lower end of the vertical tube 1 and collected in the other tank by the collection line e. When the liquid material in the tank is empty, the connections of the first and second tanks a and b to the liquid supply line c and the recovery line e are exchanged to spray the liquid material from the spray nozzle d and the antifreeze liquid. A method of freezing the liquid material on the inner wall surface of the vertical tube of the freeze-drying apparatus, wherein the liquid material is frozen in a hollow pipe shape on the inner wall surface of the vertical tube 1 by repeating the above process.

A vertical tube 1 serving as a heating surface for supplying the sublimation heat to the frozen material to be dried, and the inner wall surface 10 of the jacket surrounding the outer periphery of which the antifreeze heat medium fluid circulates; An airtight chamber 1a connected above the vertical tube 1, a trap chamber g for storing a trap i and connected to a vacuum port f provided in the airtight chamber 1a via a valve h, and storing the adjusted liquid material. At least two or more tanks a and b to be sprayed, a spray nozzle d for spraying a liquid material disposed above or inside the vertical tube 1, and a supply of liquid material in the tanks a and b to the spray nozzle d A liquid line c, a recovery line e for collecting the unfrozen portion of the liquid material sprayed from the spray nozzle d and flowing down the vertical tube 1 and sending it to the tanks a and b; alternately contacts a and b And a switching valve v2 for switching between a state in which the collection line e is connected to the tanks a and b alternately. The switching valves v1 and v2 connect the liquid supply line c to one of the tanks. A freeze-drying apparatus characterized in that when connected to a, the collection line e is controlled to be connected to the other tank b.

A tube pressurizing valve v13 for discharging pressurized air is provided in an airtight chamber 1a above the vertical tube 1 or a pipe k at a lower end side of the vertical tube 1, and is connected to the inner cavity of the vertical tube 1 and below. The inside of the pipe k is pressurized, a vent valve v14 is provided in the tanks a and b, the inside of the tank connected to the recovery line e is opened to the atmosphere, and the pipe flows through the vertical tube 1 The unfrozen liquid material flowing down to k is fed by pressure to the vertical tube 1 and one of the tanks a and b in the recovery line e by the pressure of the air supplied into the pipe k. The freeze-drying apparatus according to claim 2, wherein

An upstream side of a substantially horizontal liquid reservoir L is connected to a pipe k connected to a lower end of the vertical tube 1, and a recovery line e is connected downstream of the liquid reservoir L. The freeze-drying apparatus according to claim 2 or 3, wherein the freeze-drying apparatus is used.

A recovery line for feeding unfrozen liquid material flowing down to a pipe k connected to the lower end of the vertical tube 1 toward one of the tanks a and b by the pressure of air in the vertical tube 1. e is divided into a large-diameter collection line e1 and a small-diameter collection line e2, and a valve v9 provided in the large-diameter collection line e1 is closed due to a decrease in the pressure of air in the vertical tube 1, and a small-diameter collection line e2 is formed. The freeze-drying apparatus according to claim 2 or 3, wherein the non-freezing liquid is fed by pressure.

A bubbling prevention pipe 9 provided with side branch-shaped air discharge pipes 91 is provided in the tanks a and b, and the downstream side of the collection line e is connected to the upper end projecting upward from the tanks a and b. The freeze-drying apparatus according to claim 2 or 3, wherein: