JP2004017024A - Dry type methane fermentation method and dry type methane fermentation apparatus - Google Patents
Dry type methane fermentation method and dry type methane fermentation apparatus Download PDFInfo
- Publication number
- JP2004017024A JP2004017024A JP2002180256A JP2002180256A JP2004017024A JP 2004017024 A JP2004017024 A JP 2004017024A JP 2002180256 A JP2002180256 A JP 2002180256A JP 2002180256 A JP2002180256 A JP 2002180256A JP 2004017024 A JP2004017024 A JP 2004017024A
- Authority
- JP
- Japan
- Prior art keywords
- methane fermentation
- dry methane
- sludge
- fermentation tank
- dry
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/78—Recycling of wood or furniture waste
Landscapes
- Processing Of Solid Wastes (AREA)
- Treatment Of Sludge (AREA)
Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、畜産業、食品産業、製紙業等より発生する有機性廃棄物の乾式メタン発酵方法及び乾式メタン発酵装置に係り、特に、食品産業廃棄物、厨芥等の易分解性有機性廃棄物（有機物分解率６０〜１００％）を乾式メタン発酵処理するに当たり、発酵槽内のＮＨ４−Ｎ態窒素濃度と固形分濃度を適正に保つことにより、メタンガス生産効率を高めた乾式メタン発酵方法及び乾式メタン発酵装置に関する。
【０００２】
【従来の技術】
古紙、生ごみ、家畜糞尿などの有機性廃棄物をメタン発酵菌の作用で嫌気性分解するメタン発酵処理は、廃棄物を大幅に減容化すると共に、分解により得られるメタンガスを含むバイオガスを電気又は熱の形でエネルギー回収することができるという優れた利点を有する処理方法である。
【０００３】
このメタン発酵法には、ＴＳ（全固形物）濃度３〜５％程度でメタン発酵処理する湿式メタン発酵法と、ＴＳ濃度１５〜４０％程度でメタン発酵処理する乾式メタン発酵法とがある。
【０００４】
このうち、湿式メタン発酵法では、ＴＳ濃度が低いため、高負荷処理が困難であり、また、生ゴミや糞尿、古紙、下水汚泥等のＴＳ濃度の高い有機物を処理するためには前処理工程として可溶化処理や希釈によってＴＳ濃度を１０％以下にする必要があった。
【０００５】
これに対して、乾式メタン発酵法であれば、ＴＳ濃度の高い有機性廃棄物を複雑な前処理工程なしに高負荷で処理してバイオガスを得ることができる。即ち、乾式メタン発酵法では、発酵槽内のＴＳ濃度を高く保つことで、菌体濃度を高く保ち、発酵槽単位容積当りの有機物のガス化の速度を高めることができる。発酵槽内の菌体濃度の維持のためと、スクリューコンベアでの汚泥の搬送等の機械的操作条件を考慮した場合、乾式メタン発酵槽内の好適ＴＳ濃度は１０〜５０％程度である。
【０００６】
ところで、有機物分解率５０〜６０％程度の有機性廃棄物を原料とする乾式メタン発酵処理の場合には、ガス化を進めつつ、未分解のＴＳが発酵槽内ＴＳ濃度を１０〜５０％の好適濃度に維持するために寄与することから、良好な乾式メタン発酵を行うことが可能である。
【０００７】
しかしながら、有機物分解率が６０〜１００％の易分解性有機物を原料とする乾式メタン発酵処理の場合、未分解性ＴＳが不足し、長期連続運転に到っては乾式状態を維持するのが難しくなる。この問題を解決するために、従来においては、木材チップ等の難分解性固形物を連続的に発酵槽内に添加する方法が採用されている。
【０００８】
図２はこのような従来の乾式メタン発酵装置を示す系統図であり、有機性廃棄物は木材チップと乾式メタン発酵槽３からの返送汚泥と共に混練機１で混練される共に、蒸気を吹き込んで加温された後、投入ポンプ２で乾式メタン発酵槽３に投入され、乾式メタン発酵処理される。乾式メタン発酵槽３の底部からは乾式メタン発酵処理汚泥が引き抜かれ、引抜汚泥の一部は混練機１に返送され、残部は脱水機４で脱水処理される。脱水汚泥は炭化処理等に供され、脱水濾液は排水処理される。
【０００９】
【発明が解決しようとする課題】
しかしながら、木材チップ等の難分解性固形物を発酵槽に投入する従来の乾式メタン発酵方法では、次のような問題があった。
▲１▼ 乾式メタン発酵特有の高負荷運転を行う場合、原料中の有機態窒素が可溶化してＮＨ４−Ｎ態窒素となり、発酵槽内に蓄積する。そして、長期連続運転により、ＮＨ４−Ｎ態窒素が発酵槽内に過剰に蓄積すると、発酵阻害が起きてメタン発酵が良好に行われなくなる。
▲２▼ 未分解性有機物を含む残渣の量が多くなり、残渣の処理工程が新たに必要になる。
▲３▼ 木材チップ等の難分解性固形物の確保が必要となり、これが不足する場合には処理を行うことができない。
【００１０】
本発明は上記従来の問題点を解決し、有機物分解率６０〜１００％というような易分解性有機性廃棄物を乾式メタン発酵処理する場合であっても、木材チップ等の難分解性固形物を必要とすることなく、発酵槽内のＮＨ４−Ｎ態窒素濃度とＴＳ濃度を適正に保ち、効率的な乾式メタン発酵処理を行う乾式メタン発酵方法及び乾式メタン発酵装置を提供することを目的とする。
【００１１】
【課題を解決するための手段】
本発明の乾式メタン発酵方法は、有機性廃棄物を乾式メタン発酵槽へ供給する工程と、該乾式メタン発酵槽に供給された有機性廃棄物を乾式メタン発酵処理する乾式メタン発酵工程と、該乾式メタン発酵工程で得られる汚泥の少なくとも一部を該乾式メタン発酵槽から引き抜く汚泥引抜工程と、該汚泥引抜工程で引き抜かれた汚泥を脱水する脱水工程と、該脱水工程で得られる脱水汚泥の少なくとも一部を前記乾式メタン発酵槽へ返送する脱水汚泥返送工程とを含むことを特徴とする。
【００１２】
本発明の乾式メタン発酵装置は、有機性廃棄物を受け入れて乾式メタン発酵処理する乾式メタン発酵槽と、該乾式メタン発酵槽内の汚泥を引き抜く汚泥引抜手段と、該汚泥引抜手段で引き抜かれた汚泥を脱水する脱水機と、該脱水機により得られる脱水汚泥の少なくとも一部を前記乾式メタン発酵槽へ返送する脱水汚泥返送手段とを備えたことを特徴とする。
【００１３】
本発明では、乾式メタン発酵槽内の汚泥を脱水し、好ましくはこの脱水汚泥のＴＳ濃度を水添加により調整した後乾式メタン発酵槽に返送する。このため、脱水汚泥中の固形分により乾式メタン発酵槽内のＴＳ濃度を乾式メタン発酵処理に好適な１０〜５０％に維持することができ、このため槽内菌体濃度を高く維持することができる。
【００１４】
また、乾式メタン発酵の阻害因子であるＮＨ４−Ｎ態窒素を脱水濾液として系外に排出することができるため、乾式メタン発酵槽内のＮＨ４−Ｎ態窒素の蓄積を防止することができる。更に、脱水ケーキ中に炭酸塩が形成されており、これを返送することにより、乾式メタン発酵槽内のアルカリ度を高く維持することもできる。
【００１５】
この結果、処理する有機性廃棄物の性状にかかわらず、難分解性の有機性廃棄物であっても易分解性の有機性廃棄物であっても、良好な乾式メタン発酵処理を行うことが可能となる。また、ＮＨ４−Ｎ態窒素の排出、アルカリ度の向上効果により、返送された脱水汚泥中の未分解物も分解することが可能となり、発酵残渣量を大幅に低減することが可能となる。
【００１６】
引抜汚泥の脱水処理で得られる脱水濾液中には、メタン発酵過程で有機性廃棄物から可溶化した揮発性脂肪酸（ＶＦＡ）が含まれており、このため、このＶＦＡを脱窒反応の水素供与体として脱水濾液中のＮＨ４−Ｎ態窒素を既設の硝化・脱窒処理設備で効率的に脱窒処理することができる。
【００１７】
【発明の実施の形態】
以下に本発明の乾式メタン発酵方法及び乾式メタン発酵装置の実施の形態を図面を参照しながら詳細に説明する。
【００１８】
図１は本発明の乾式メタン発酵装置の実施の形態を示す系統図である。
【００１９】
生ゴミ、家畜糞尿、下水処理場等から発生する汚泥などの有機性廃棄物は、必要に応じて破砕した後、発酵原料貯槽５に貯留される。
【００２０】
有機性廃棄物の処理に当っては、発酵原料貯槽５内の有機性廃棄物を混練機１に投入し、乾式メタン発酵槽３の底部から引き抜いた返送汚泥と混練すると共に蒸気を吹き込んで加温する。この加温温度は、通常の場合、高温メタン発酵であれば５２〜５７℃、中温メタン発酵であれば３５〜４０℃程度である。
【００２１】
有機性廃棄物と返送汚泥との混合割合は、通常の場合、有機性廃棄物１００重量部に対して返送汚泥１００〜３０００重量部とされるが、何らこの割合に限定されるものではない。なお、この有機性廃棄物と返送汚泥との混練に当っては必要に応じて更に水が添加混練される。
【００２２】
混練機１で返送汚泥と混練されると共に蒸気で加温された有機性廃棄物は、投入ポンプ２により乾式メタン発酵槽３に投入され、乾式メタン発酵処理される。
【００２３】
有機性廃棄物は、メタン生成菌を含む返送汚泥と混練機１で混練されると共に蒸気で加温されているため、この乾式メタン発酵槽３での加温、撹拌操作は不要である。
【００２４】
乾式メタン発酵槽３に投入された有機性廃棄物は、乾式メタン発酵処理で分解され、ＴＳ濃度が低下し、発酵槽３の下部へ移動する。
【００２５】
この乾式メタン発酵槽３の底部からは、汚泥を引き抜き、脱水機４で脱水処理する。この脱水処理に当っては、鉄塩の無機凝集剤（３８％製品）を有効成分量として、汚泥のＴＳ当り１〜１０重量％添加しても良いが、汚泥の性状によっては無薬注とすることもできる。脱水機４で脱水処理して得られた脱水汚泥（脱水ケーキ）は、必要に応じて一部を発酵残渣として系外へ排出し、残部を乾式メタン発酵槽１の固形分源として混練機１に送給する。
【００２６】
混練機１では、返送された脱水汚泥に必要量の水（工水）を、添加、混練してＴＳ濃度を調整すると共に、蒸気を吹き込んで、メタン発酵のための所定の温度に加温した後、投入ポンプ２で乾式メタン発酵槽３に投入する。
【００２７】
一方、脱水濾液（汚泥脱離液）は、メタン発酵で生成した可溶性のＮＨ４−Ｎ態窒素を含むと共に、同様に生成したＶＦＡを含むものであるため、含有されるＶＦＡを水素供与体として、硝化・脱窒処理設備にて効率的に脱窒処理することができる。
【００２８】
本発明では、この脱水濾液を系外へ排出することにより、乾式メタン発酵槽３内のＮＨ４−Ｎ態窒素濃度を３０００ｍｇ／Ｌ以下、特に５００〜２０００ｍｇ／Ｌに維持することが好ましい。
【００２９】
従って、乾式メタン発酵槽３から引き抜いて脱水に供する汚泥は、乾式メタン発酵槽３内のＮＨ４−Ｎ態窒素濃度を上記範囲に維持できるような量とすることが好ましい。この脱水に供する引抜汚泥量は、処理する有機性廃棄物の性状や、乾式メタン発酵処理条件、脱水条件等によっても異なるが、一般的には、投入した有機性廃棄物１００重量部に対して２００〜３００重量部程度である。
【００３０】
また、本発明では、脱水汚泥を乾式メタン発酵槽３内に返送することにより、乾式メタン発酵槽３内のＴＳ濃度を乾式メタン発酵処理に好適な１０〜５０％の範囲に維持するものである。
【００３１】
従って、脱水汚泥の乾式メタン発酵槽３への返送は、このように乾式メタン発酵槽３内のＴＳ濃度を、乾式メタン発酵処理に好適なＴＳ濃度１０〜５０％の範囲に維持することができるように行えば良く、脱水汚泥の返送量や水添加によるＴＳ濃度の調整値等は、処理する有機性廃棄物の性状や乾式メタン発酵処理条件、汚泥性状等に基いて適宜調整される。一般的には、乾式メタン発酵槽３から引き抜き、脱水して得られたＴＳ濃度２０〜４０％程度の脱水汚泥のうちの７０〜１００％を乾式メタン発酵槽３に返送し、残部を発酵残渣として系外へ排出するのが好ましい。また、乾式メタン発酵槽３に投入する脱水汚泥は、必要に応じて水を添加することによりＴＳ濃度２０〜５０％に調整することが好ましい。
【００３２】
この脱水汚泥は、有機性廃棄物と混合して乾式メタン発酵槽３に返送しても良いが、返送汚泥や有機性廃棄物の投入制御を簡易化するために、有機性廃棄物は乾式メタン発酵槽３から引き抜いた返送汚泥と混練して乾式メタン発酵槽３に投入し、脱水汚泥は、この有機性廃棄物とは別に水添加によるＴＳ濃度調整後乾式メタン発酵槽３に投入するのが好ましい。
【００３３】
このため、図１の装置では、乾式メタン発酵槽３からの汚泥の引き抜き及び脱水と脱水汚泥の返送を行う時には、有機性廃棄物の乾式メタン発酵槽３への投入を停止し、系内に導入される有機性廃棄物を貯留するために、発酵原料貯槽５が設けられている。この発酵原料貯槽５は、槽内の貯留量を重量計や光学式、超音波式などのレベル計で監視しておくことが好ましく、この貯留量によって、脱水汚泥の返送処理時期を判断するようにすることが好ましい。即ち、貯留量が多い場合には、脱水汚泥の返送処理を行わずに有機性廃棄物の投入を行って貯留量を減らし、貯留量が少ないときに脱水汚泥の返送処理を行うことにより、円滑な処理が行える。
【００３４】
また、乾式メタン発酵槽３にはレベル検出器（フロート式センサや静電容量検出式センサ等）を設け、発酵槽３内の汚泥レベルに基いて汚泥の引き抜き処理を行うことが、安全性の面から好ましく、これにより、汚泥の引き抜き、返送等の処理を確実に行うことができる。
【００３５】
【実施例】
以下に実施例及び比較例を挙げて本発明をより具体的に説明する。
【００３６】
実施例１
図１に示す乾式メタン発酵装置を用いて、ＴＳ濃度６５％の原料の乾式メタン発酵処理を行った。この原料は有機物分解率８５〜９５％の易分解性の有機性廃棄物である。
【００３７】
１日当たり約２０ｋｇの原料と約１００ｋｇの引抜汚泥とを混練機１で混練し、蒸気を吹き込んで５２〜５７℃に加温した後、投入ポンプ２で乾式メタン発酵槽３に投入した。
【００３８】
乾式メタン発酵槽（容量１ｍ３）３からは１日当たり約５５ｋｇの汚泥（ＴＳ濃度１５．３％（潤滑状態））を引き抜き、凝集剤として３８重量％塩化鉄水溶液を汚泥中のＴＳに対して５重量％の有効成分添加濃度となるように添加した後遠心脱水機４で脱水した。得られた脱水汚泥約２７ｋｇの一部は系外へ発酵残渣として排出し、残部は混練機１に移送し、水を加えてＴＳ濃度を調整し、上記と同様に加温した後乾式メタン発酵槽３に投入した。即ち、脱水汚泥のＴＳ濃度は３０％であったため、この脱水汚泥２２ｋｇに水１７Ｌを添加してＴＳ濃度２５％に調整して乾式メタン発酵槽３に投入した。
【００３９】
上記操作により、約２５００〜３０００ｍｇ／ｋｇのＮＨ４−Ｎ態窒素を含む脱水濾液を１日当たり約２７Ｌ排出したことにより、１日当たり約０．０８ｋｇのＮＨ４−Ｎ態窒素を系外へ排出することができ、乾式メタン発酵槽３内のＮＨ４−Ｎ態窒素濃度を１５００〜２５００ｍｇ／ｋｇに保つことができた。また、脱水汚泥の返送で乾式メタン発酵槽３内のＴＳ濃度を約１５％に保つことができた。
【００４０】
この乾式メタン発酵処理で、原料１ｋｇ当たり約４００Ｌのバイオガスを発生させることができ、原料１ｋｇ当たりに発生した発酵残渣の排出量は約０．１５ｋｇであった。
【００４１】
一方、引抜汚泥の脱水濾液は原料の乾式メタン発酵処理で可溶化した揮発性脂肪酸（ＶＦＡ）約２０００ｍｇ／Ｌを含むものであり、このＶＦＡが脱窒反応の水素供与体となるため、通常の硝化・脱窒処理により効率的に処理することができる。
【００４２】
以上の結果を表１にまとめて記載した。
【００４３】
比較例１
図２に示す従来の乾式メタン発酵装置を用いて、実施例１で処理したものと同様の原料を乾式メタン発酵処理した。
【００４４】
１日当たり約２０ｋｇの原料と約１００ｋｇの引抜汚泥と木材チップ約４ｋｇと水を混練機１で混練し、蒸気を吹き込んで５２〜５７℃に加温した後、投入ポンプで乾式メタン発酵槽３に投入した。
【００４５】
乾式メタン発酵槽３からは１日当たり約１５ｋｇの汚泥（ＴＳ濃度１５．３％（潤滑状態））に凝集剤として３８重量％塩化鉄水溶液を汚泥中のＴＳに対して５重量％の有効成分添加濃度となるように添加して遠心脱水機４で脱水し、脱水汚泥及び脱水濾液を系外へ排出した。
【００４６】
この乾式メタン発酵処理における乾式メタン発酵処理槽内のＴＳ濃度及びＮＨ４−Ｎ態窒素濃度、発生バイオガス量、発酵残渣排出量、脱水濾液の性状は表１に示す通りであり、実施例１に比べてバイオガスの発生量は少なく、一方で発酵残渣の排出量は多かった。
【００４７】
この比較例では、運転を更に継続することにより、運転開始から３０日後には乾式メタン発酵処理槽のＮＨ４−Ｎ態窒素濃度は３０００ｍｇ／Ｌとなり、ＮＨ４−Ｎ態窒素による発酵阻害でバイオガス発生量は１／３に減少した。
【００４８】
【表１】
【発明の効果】
以上詳述した通り、本発明の乾式メタン発酵方法及び乾式メタン発酵装置によれば、有機性廃棄物の乾式メタン発酵処理において、発酵槽内のＮＨ４−Ｎ態窒素濃度とＴＳ濃度を適正に保ち、効率的な乾式メタン発酵処理を長期連続運転にて行うことが可能となり、メタンガス生産効率を高めると共に、発酵残渣量を低減してその処理系統の負荷を大幅に軽減することができる。
【図面の簡単な説明】
【図１】本発明の乾式メタン発酵装置の実施の形態を示す系統図である。
【図２】従来の乾式メタン発酵装置を示す系統図である。
【符号の説明】
１ 混練機
２ 投入ポンプ
３ 乾式メタン発酵槽
４ 脱水機
５ 発酵原料貯槽[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dry methane fermentation method and a dry methane fermentation apparatus for organic waste generated from the livestock industry, the food industry, the papermaking industry, etc., and in particular, food industry waste, easily decomposable organic waste such as kitchen waste. In performing dry methane fermentation treatment of (organic matter decomposition rate: 60 to 100%), a dry methane fermentation method in which methane gas production efficiency is enhanced by appropriately maintaining the NH 4 —N-state nitrogen concentration and the solid concentration in the fermenter. It relates to a dry methane fermentation apparatus.
[0002]
[Prior art]
The methane fermentation treatment, which anaerobically decomposes organic waste such as waste paper, garbage, and livestock manure by the action of methane fermentation bacteria, significantly reduces the volume of waste and biogas containing methane gas obtained by decomposition. This is a processing method having an excellent advantage that energy can be recovered in the form of electricity or heat.
[0003]
The methane fermentation method includes a wet methane fermentation method in which methane fermentation is performed at a TS (total solid matter) concentration of about 3 to 5%, and a dry methane fermentation method in which methane fermentation is performed at a TS concentration of about 15 to 40%.
[0004]
Of these, in the wet methane fermentation method, high TS treatment is difficult due to low TS concentration, and a pretreatment step is required to treat organic substances having a high TS concentration such as garbage, manure, waste paper, sewage sludge, and the like. It was necessary to reduce the TS concentration to 10% or less by solubilization or dilution.
[0005]
In contrast, in the case of the dry methane fermentation method, biogas can be obtained by treating an organic waste having a high TS concentration with a high load without a complicated pretreatment step. That is, in the dry methane fermentation method, by keeping the TS concentration in the fermenter high, the cell concentration can be kept high and the rate of gasification of organic matter per unit volume of the fermenter can be increased. In consideration of the maintenance of the cell concentration in the fermenter and the mechanical operation conditions such as the transport of sludge on a screw conveyor, the preferred TS concentration in the dry methane fermenter is about 10 to 50%.
[0006]
By the way, in the case of dry methane fermentation treatment using an organic waste having an organic matter decomposition rate of about 50 to 60% as a raw material, undecomposed TS reduces the TS concentration in the fermenter to 10 to 50% while promoting gasification. Since it contributes to maintain a suitable concentration, good dry methane fermentation can be performed.
[0007]
However, in the case of dry methane fermentation treatment using a readily decomposable organic material having an organic matter decomposition rate of 60 to 100%, undecomposable TS is insufficient, and it is difficult to maintain a dry state for long-term continuous operation. Become. In order to solve this problem, conventionally, a method of continuously adding a hardly decomposable solid such as wood chips into a fermenter has been adopted.
[0008]
FIG. 2 is a system diagram showing such a conventional dry methane fermentation apparatus. Organic waste is kneaded in a kneader 1 together with wood chips and returned sludge from a dry methane fermentation tank 3, and steam is blown into the waste. After being heated, it is charged into the dry methane fermentation tank 3 by the charging pump 2 and subjected to dry methane fermentation. Dry methane fermentation-treated sludge is drawn out from the bottom of the dry methane fermentation tank 3, a part of the drawn-out sludge is returned to the kneader 1, and the rest is dewatered by a dehydrator 4. The dewatered sludge is subjected to a carbonization treatment or the like, and the dewatered filtrate is subjected to a drainage treatment.
[0009]
[Problems to be solved by the invention]
However, the conventional dry methane fermentation method in which a hardly decomposable solid such as wood chips is put into a fermenter has the following problems.
{Circle around (1)} When performing a high-load operation peculiar to dry methane fermentation, organic nitrogen in the raw material is solubilized into NH 4 —N nitrogen and accumulated in the fermenter. Then, when NH 4 —N-state nitrogen excessively accumulates in the fermenter by long-term continuous operation, fermentation is inhibited and methane fermentation cannot be performed well.
{Circle around (2)} The amount of the residue containing the non-decomposable organic matter increases, and a residue treatment step is newly required.
{Circle around (3)} It is necessary to secure hard-to-decompose solids such as wood chips, and if this is insufficient, the treatment cannot be performed.
[0010]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. Even when a readily decomposable organic waste having an organic matter decomposition rate of 60 to 100% is subjected to dry methane fermentation, hardly decomposable solids such as wood chips are obtained. It is an object of the present invention to provide a dry methane fermentation method and a dry methane fermentation apparatus for performing an efficient dry methane fermentation process while maintaining the NH 4 —N-state nitrogen concentration and the TS concentration in a fermentation tank properly without the need for methane fermentation. And
[0011]
[Means for Solving the Problems]
The dry methane fermentation method of the present invention comprises: a step of supplying organic waste to a dry methane fermentation tank; and a dry methane fermentation step of dry methane fermentation of the organic waste supplied to the dry methane fermentation tank. A sludge extraction step of extracting at least a part of the sludge obtained in the dry methane fermentation step from the dry methane fermentation tank, a dehydration step of dewatering the sludge extracted in the sludge extraction step, and a dehydration sludge obtained in the dehydration step. A dewatered sludge return step of returning at least a portion to the dry methane fermentation tank.
[0012]
The dry methane fermentation apparatus of the present invention is a dry methane fermentation tank that receives organic waste and performs dry methane fermentation treatment, sludge extraction means for extracting sludge in the dry methane fermentation tank, and is extracted by the sludge extraction means. It is characterized by comprising a dehydrator for dewatering sludge, and a dewatered sludge return means for returning at least a part of the dewatered sludge obtained by the dewaterer to the dry methane fermentation tank.
[0013]
In the present invention, the sludge in the dry methane fermentation tank is dewatered, and preferably the TS concentration of the dewatered sludge is adjusted by adding water, and then returned to the dry methane fermentation tank. Therefore, the TS concentration in the dry methane fermentation tank can be maintained at 10 to 50%, which is suitable for the dry methane fermentation treatment, by the solid content in the dewatered sludge. it can.
[0014]
Further, since it is possible to discharge the NH 4 -N nitrogen as inhibitors of dry methane fermentation system as dehydrated filtrate, it is possible to prevent the accumulation of NH 4 -N nitrogen dry methane fermentation tank . Furthermore, carbonate is formed in the dehydrated cake, and by returning this, the alkalinity in the dry methane fermentation tank can be maintained high.
[0015]
As a result, regardless of the nature of the organic waste to be treated, good dry methane fermentation can be performed regardless of whether it is a persistent organic waste or a readily degradable organic waste. It becomes possible. In addition, due to the effects of discharging NH 4 —N-state nitrogen and improving alkalinity, undecomposed products in the returned dewatered sludge can be decomposed, and the amount of fermentation residue can be significantly reduced.
[0016]
The dehydrated filtrate obtained by the dewatering treatment of the extracted sludge contains volatile fatty acids (VFA) solubilized from organic wastes during the methane fermentation process. NH 4 —N-state nitrogen in the dehydrated filtrate can be efficiently denitrified by the existing nitrification / denitrification treatment equipment.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a dry methane fermentation method and a dry methane fermentation apparatus of the present invention will be described in detail with reference to the drawings.
[0018]
FIG. 1 is a system diagram showing an embodiment of the dry methane fermentation apparatus of the present invention.
[0019]
Organic wastes such as garbage, livestock manure, and sludge generated from sewage treatment plants are crushed as necessary and then stored in the fermentation raw
[0020]
In the treatment of the organic waste, the organic waste in the fermentation raw
[0021]
The mixing ratio of the organic waste and the returned sludge is usually 100 to 3000 parts by weight of the returned sludge based on 100 parts by weight of the organic waste, but is not limited to this ratio. When kneading the organic waste and the returned sludge, water is further added and kneaded as necessary.
[0022]
The organic waste that has been kneaded with the returned sludge in the kneader 1 and heated with steam is charged into the dry methane fermentation tank 3 by the charging pump 2 and subjected to dry methane fermentation.
[0023]
Since the organic waste is kneaded with the returned sludge containing methane-producing bacteria in the kneader 1 and heated with steam, the heating and stirring operations in the dry methane fermentation tank 3 are unnecessary.
[0024]
The organic waste put into the dry methane fermentation tank 3 is decomposed by the dry methane fermentation treatment, the TS concentration decreases, and moves to the lower part of the fermentation tank 3.
[0025]
Sludge is extracted from the bottom of the dry methane fermentation tank 3 and dewatered by a dehydrator 4. In this dehydration treatment, an inorganic coagulant of iron salt (38% product) may be added as an active ingredient in an amount of 1 to 10% by weight per TS of sludge, but depending on the properties of the sludge, non-chemical injection may be required. You can also. The dewatered sludge (dewatered cake) obtained by the dewatering treatment in the dewatering machine 4 is partially discharged as a fermentation residue out of the system as necessary, and the remainder is used as a kneader 1 as a solid source in the dry methane fermentation tank 1. To be sent to
[0026]
In the kneading machine 1, a required amount of water (industrial water) was added to the returned dewatered sludge, kneaded to adjust the TS concentration, and steam was blown to heat the mixture to a predetermined temperature for methane fermentation. Thereafter, the mixture is charged into the dry methane fermentation tank 3 by the charging pump 2.
[0027]
On the other hand, the dehydrated filtrate (sludge desorbed solution) contains soluble NH 4 —N-state nitrogen produced by methane fermentation and also contains VFA produced in the same manner. Therefore, nitrification is carried out using the contained VFA as a hydrogen donor.・ Denitrification treatment can be performed efficiently by the denitrification treatment equipment.
[0028]
In the present invention, it is preferable to maintain the concentration of NH 4 —N nitrogen in the dry methane fermentation tank 3 at 3000 mg / L or less, particularly 500 to 2000 mg / L, by discharging the dehydrated filtrate to the outside of the system.
[0029]
Therefore, it is preferable that the amount of sludge pulled out from the dry methane fermentation tank 3 and used for dehydration is such that the concentration of NH 4 —N-state nitrogen in the dry methane fermentation tank 3 can be maintained in the above range. The amount of the extracted sludge to be subjected to the dehydration varies depending on the properties of the organic waste to be treated, the dry methane fermentation treatment conditions, the dehydration conditions, and the like. It is about 200 to 300 parts by weight.
[0030]
Further, in the present invention, the TS concentration in the dry methane fermentation tank 3 is maintained in a range of 10 to 50% suitable for the dry methane fermentation treatment by returning the dehydrated sludge into the dry methane fermentation tank 3. .
[0031]
Therefore, the return of the dehydrated sludge to the dry methane fermentation tank 3 can maintain the TS concentration in the dry methane fermentation tank 3 in the range of 10 to 50% suitable for the dry methane fermentation treatment. The return amount of the dewatered sludge and the adjusted value of the TS concentration by adding water are appropriately adjusted based on the properties of the organic waste to be treated, dry methane fermentation treatment conditions, sludge properties, and the like. Generally, 70 to 100% of the dewatered sludge having a TS concentration of about 20 to 40% obtained by extracting from the dry methane fermentation tank 3 and dewatering is returned to the dry methane fermentation tank 3, and the remainder is fermentation residue. It is preferable to discharge it out of the system. It is preferable that the dewatered sludge introduced into the dry methane fermentation tank 3 is adjusted to a TS concentration of 20 to 50% by adding water as needed.
[0032]
This dewatered sludge may be mixed with organic waste and returned to the dry methane fermentation tank 3. However, in order to simplify input control of returned sludge and organic waste, organic waste is treated with dry methane fermentation. It is kneaded with the returned sludge extracted from the fermentation tank 3 and put into the dry methane fermentation tank 3. The dewatered sludge is put into the dry methane fermentation tank 3 after adjusting the TS concentration by adding water separately from this organic waste. preferable.
[0033]
For this reason, in the apparatus of FIG. 1, when sludge is pulled out from the dry methane fermentation tank 3 and dewatering and return of the dehydrated sludge are performed, the input of the organic waste into the dry methane fermentation tank 3 is stopped, and A fermentation raw
[0034]
The dry methane fermentation tank 3 is provided with a level detector (a float type sensor, a capacitance detection type sensor, etc.), and it is possible to perform a sludge extraction process based on the sludge level in the fermentation tank 3. This is preferable from the aspect of the present invention, whereby the processes such as sludge extraction and return can be reliably performed.
[0035]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.
[0036]
Example 1
Using the dry methane fermentation apparatus shown in FIG. 1, a dry methane fermentation treatment of a raw material having a TS concentration of 65% was performed. This raw material is an easily decomposable organic waste having an organic matter decomposition rate of 85 to 95%.
[0037]
About 20 kg of the raw material and about 100 kg of the extracted sludge per day were kneaded by the kneading machine 1, heated to 52 to 57 ° C. by blowing steam, and then charged into the dry methane fermentation tank 3 by the charging pump 2.
[0038]
About 55 kg of sludge (TS concentration: 15.3% (lubricated state)) is withdrawn from the dry methane fermentation tank (capacity: 1 m 3 ) 3 per day, and a 38% by weight aqueous solution of iron chloride is used as a flocculant for TS in the sludge. After adding the active ingredient to a concentration of 5% by weight, the mixture was dehydrated with a centrifugal dehydrator 4. A part of the obtained dewatered sludge of about 27 kg is discharged out of the system as a fermentation residue, and the remainder is transferred to the kneader 1, water is added to adjust the TS concentration, and the mixture is heated in the same manner as above, and then dried methane fermentation. It was put into the tank 3. That is, since the TS concentration of the dewatered sludge was 30%, 17 L of water was added to 22 kg of the dewatered sludge to adjust the TS concentration to 25%, and then the sludge was put into the dry methane fermentation tank 3.
[0039]
By the operation, by which the dehydrated filtrate per day to about 27L discharge containing NH 4 -N nitrogen of about 2500~3000mg / kg, to discharge the NH 4 -N nitrogen per day to about 0.08kg out of the system As a result, the concentration of NH 4 —N nitrogen in the dry methane fermentation tank 3 was maintained at 1500 to 2500 mg / kg. Also, the TS concentration in the dry methane fermentation tank 3 could be maintained at about 15% by returning the dehydrated sludge.
[0040]
In this dry methane fermentation treatment, about 400 L of biogas could be generated per kg of raw material, and the amount of fermentation residue generated per kg of raw material was about 0.15 kg.
[0041]
On the other hand, the dewatered filtrate of the extracted sludge contains about 2,000 mg / L of volatile fatty acid (VFA) solubilized by the dry methane fermentation treatment of the raw material, and this VFA becomes a hydrogen donor for the denitrification reaction. It can be treated efficiently by nitrification and denitrification.
[0042]
The above results are summarized in Table 1.
[0043]
Comparative Example 1
Using the conventional dry methane fermentation apparatus shown in FIG. 2, the same raw materials as those treated in Example 1 were subjected to dry methane fermentation.
[0044]
About 20 kg of raw material per day, about 100 kg of extracted sludge, about 4 kg of wood chips and water are kneaded in a kneading machine 1 and heated to 52 to 57 ° C. by blowing steam, and then put into a dry methane fermentation tank 3 by an input pump. I put it in.
[0045]
From the dry methane fermentation tank 3, a 38% by weight aqueous solution of iron chloride is added as a coagulant to about 15 kg of sludge (TS concentration 15.3% (lubricated state)) per day, and 5% by weight of TS in the sludge is added. The mixture was added to a concentration and dehydrated by the centrifugal dehydrator 4, and the dehydrated sludge and the dehydrated filtrate were discharged out of the system.
[0046]
In this dry methane fermentation treatment, the TS concentration and NH 4 —N-nitrogen concentration in the dry methane fermentation treatment tank, the amount of generated biogas, the amount of fermentation residue discharged, and the properties of the dehydrated filtrate are as shown in Table 1. The amount of biogas generated was smaller than that of, while the amount of fermentation residue discharged was larger.
[0047]
In this comparative example, by continuing the operation, the NH 4 —N-state nitrogen concentration of the dry methane fermentation treatment tank became 3000 mg / L after 30 days from the start of the operation, and the fermentation was inhibited by NH 4 —N-state nitrogen. The amount of gas generation was reduced to one third.
[0048]
[Table 1]
【The invention's effect】
As described above in detail, according to the dry methane fermentation method and the dry methane fermentation apparatus of the present invention, in the dry methane fermentation treatment of organic waste, the NH 4 —N nitrogen concentration and the TS concentration in the fermenter are properly adjusted. It is possible to maintain and efficiently perform dry methane fermentation in long-term continuous operation, increase methane gas production efficiency, reduce the amount of fermentation residue, and greatly reduce the load on the treatment system.
[Brief description of the drawings]
FIG. 1 is a system diagram showing an embodiment of a dry methane fermentation apparatus of the present invention.
FIG. 2 is a system diagram showing a conventional dry methane fermentation apparatus.
[Explanation of symbols]
1 kneading machine 2 input pump 3 dry methane fermentation tank 4
Claims (5)
該乾式メタン発酵槽に供給された有機性廃棄物を乾式メタン発酵処理する乾式メタン発酵工程と、
該乾式メタン発酵工程で得られる汚泥の少なくとも一部を該乾式メタン発酵槽から引き抜く汚泥引抜工程と、
該汚泥引抜工程で引き抜かれた汚泥を脱水する脱水工程と、
該脱水工程で得られる脱水汚泥の少なくとも一部を前記乾式メタン発酵槽へ返送する脱水汚泥返送工程と
を有することを特徴とする乾式メタン発酵方法。Supplying organic waste to a dry methane fermentation tank;
A dry methane fermentation step of dry methane fermentation of the organic waste supplied to the dry methane fermentation tank;
A sludge extraction step of extracting at least a part of the sludge obtained in the dry methane fermentation step from the dry methane fermentation tank,
A dewatering step of dewatering the sludge extracted in the sludge extraction step,
A dewatered sludge return step of returning at least a part of the dewatered sludge obtained in the dewatering step to the dry methane fermentation tank.
該乾式メタン発酵槽内の汚泥を引き抜く汚泥引抜手段と、
該汚泥引抜手段で引き抜かれた汚泥を脱水する脱水機と、
該脱水機により得られる脱水汚泥の少なくとも一部を前記乾式メタン発酵槽へ返送する脱水汚泥返送手段と
を備えたことを特徴とする乾式メタン発酵装置。A dry methane fermentation tank that receives organic waste and performs dry methane fermentation,
Sludge extraction means for extracting sludge in the dry methane fermentation tank,
A dehydrator for dehydrating the sludge extracted by the sludge extraction means,
A dewatering sludge return means for returning at least a part of the dewatered sludge obtained by the dehydrator to the dry methane fermentation tank.
該貯留槽内の有機性廃棄物を前記乾式メタン発酵槽に送出する送出手段とを備えたことを特徴とする乾式メタン発酵装置。A storage tank for storing organic waste,
A dry methane fermentation apparatus, comprising: sending means for sending organic waste in the storage tank to the dry methane fermentation tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002180256A JP4337307B2 (en) | 2002-06-20 | 2002-06-20 | Dry methane fermentation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002180256A JP4337307B2 (en) | 2002-06-20 | 2002-06-20 | Dry methane fermentation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004017024A true JP2004017024A (en) | 2004-01-22 |
| JP4337307B2 JP4337307B2 (en) | 2009-09-30 |
Family
ID=31177438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002180256A Expired - Fee Related JP4337307B2 (en) | 2002-06-20 | 2002-06-20 | Dry methane fermentation method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4337307B2 (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004290729A (en) * | 2003-03-25 | 2004-10-21 | Kurita Water Ind Ltd | Apparatus for digestion treatment of organic waste liquid |
| JP2005279411A (en) * | 2004-03-29 | 2005-10-13 | Kurita Water Ind Ltd | High-speed methane fermentation process of glycerol |
| JP2006272138A (en) * | 2005-03-29 | 2006-10-12 | Fuji Electric Holdings Co Ltd | Organic waste treatment method |
| JP2007038057A (en) * | 2005-08-01 | 2007-02-15 | Shinzo Ito | Dry type methane fermentation method |
| JP2007098228A (en) * | 2005-09-30 | 2007-04-19 | Kurita Water Ind Ltd | Method and apparatus for treatment of organic waste |
| JP2007098229A (en) * | 2005-09-30 | 2007-04-19 | Kurita Water Ind Ltd | Method and apparatus for treating organic waste material |
| JP2007216168A (en) * | 2006-02-17 | 2007-08-30 | Kurita Water Ind Ltd | Method and apparatus for treating organic waste |
| JP2008086869A (en) * | 2006-09-29 | 2008-04-17 | Kubota Corp | Organic waste treatment apparatus and organic waste treatment method |
| JP2011143326A (en) * | 2010-01-12 | 2011-07-28 | Takuma Co Ltd | Dry type methane fermentation residue dehydration system |
| JP2012011265A (en) * | 2010-06-29 | 2012-01-19 | Takuma Co Ltd | Methane fermentation residue dehydration system |
| WO2017203781A1 (en) * | 2016-05-24 | 2017-11-30 | 日本プライスマネジメント株式会社 | Methane fermentation device |
| WO2023223549A1 (en) * | 2022-05-20 | 2023-11-23 | 株式会社クボタ | Organic waste treatment method |
-
2002
- 2002-06-20 JP JP2002180256A patent/JP4337307B2/en not_active Expired - Fee Related
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004290729A (en) * | 2003-03-25 | 2004-10-21 | Kurita Water Ind Ltd | Apparatus for digestion treatment of organic waste liquid |
| JP2005279411A (en) * | 2004-03-29 | 2005-10-13 | Kurita Water Ind Ltd | High-speed methane fermentation process of glycerol |
| JP2006272138A (en) * | 2005-03-29 | 2006-10-12 | Fuji Electric Holdings Co Ltd | Organic waste treatment method |
| JP4729718B2 (en) * | 2005-03-29 | 2011-07-20 | 富士電機株式会社 | Organic waste treatment methods |
| JP4541245B2 (en) * | 2005-08-01 | 2010-09-08 | 株式会社 ユーリカ エンジニアリング | Dry methane fermentation |
| JP2007038057A (en) * | 2005-08-01 | 2007-02-15 | Shinzo Ito | Dry type methane fermentation method |
| JP2007098228A (en) * | 2005-09-30 | 2007-04-19 | Kurita Water Ind Ltd | Method and apparatus for treatment of organic waste |
| JP4665693B2 (en) * | 2005-09-30 | 2011-04-06 | 栗田工業株式会社 | Method and apparatus for treating organic waste |
| JP2007098229A (en) * | 2005-09-30 | 2007-04-19 | Kurita Water Ind Ltd | Method and apparatus for treating organic waste material |
| JP2007216168A (en) * | 2006-02-17 | 2007-08-30 | Kurita Water Ind Ltd | Method and apparatus for treating organic waste |
| JP2008086869A (en) * | 2006-09-29 | 2008-04-17 | Kubota Corp | Organic waste treatment apparatus and organic waste treatment method |
| JP4707637B2 (en) * | 2006-09-29 | 2011-06-22 | 株式会社クボタ | Organic waste treatment apparatus and organic waste treatment method |
| JP2011143326A (en) * | 2010-01-12 | 2011-07-28 | Takuma Co Ltd | Dry type methane fermentation residue dehydration system |
| JP2012011265A (en) * | 2010-06-29 | 2012-01-19 | Takuma Co Ltd | Methane fermentation residue dehydration system |
| WO2017203781A1 (en) * | 2016-05-24 | 2017-11-30 | 日本プライスマネジメント株式会社 | Methane fermentation device |
| WO2023223549A1 (en) * | 2022-05-20 | 2023-11-23 | 株式会社クボタ | Organic waste treatment method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4337307B2 (en) | 2009-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4865828B2 (en) | Anaerobic integrated process equipment for organic waste treatment | |
| KR100943315B1 (en) | Apparatus and method for treating organic sludge using thermal hydrolysis and high-temperature anaerobic digestion | |
| JP4512823B2 (en) | Organic waste treatment method and treatment system | |
| KR20170088176A (en) | Anaerobic digestion system of organic waste through the thermal hydrolysis | |
| JP4337307B2 (en) | Dry methane fermentation method | |
| KR100894154B1 (en) | Apparatus and methods of a successive treatment of organic sludges for producing solid-liquid slurry containing solids and secessional liquids from organic sludge | |
| JP2007203213A (en) | Method and apparatus for treating highly wet waste before hydration, and dehydration system equipped with this apparatus | |
| JP2000015231A (en) | Method for methane fermentation of organic waste | |
| KR101276758B1 (en) | Continuous aerobic and anaerobic dry fermentation system and method | |
| KR100972178B1 (en) | Apparatus for anaerobic treatment of organic waste and method there of | |
| KR101123854B1 (en) | Wet-dry serial parallel anaerobic digestion apparatus and method for treating organic waste | |
| CN112075320A (en) | System and method for preparing organic nutrient soil from urban domestic sludge, organic nutrient soil and application | |
| JP2003094022A (en) | Organic waste treatment method and device therefor | |
| JP3554689B2 (en) | Waste disposal method | |
| Vergote et al. | Stability of thermophilic pig manure mono-digestion: effect of thermal pre-treatment and separation | |
| JP2020157261A (en) | Organic sludge treatment method and treatment apparatus | |
| KR100851898B1 (en) | Improvement methods of digestion efficiency on drying anaerobic digestion process | |
| JP4631204B2 (en) | Dry methane fermentation of organic waste | |
| JP4543504B2 (en) | Dry methane fermentation method for organic waste | |
| KR100286180B1 (en) | Biogas method and plant of living waste and animal carcass | |
| KR20040105933A (en) | Method for the efficient treatment of organic waste | |
| JP2019141778A (en) | Anaerobic digestion tank startup method and anaerobic digestion system | |
| JP2004057859A (en) | Treatment method of methane fermentation residue and equipment therefor | |
| KR100973786B1 (en) | Anaerobic digestion method of organic waste having high salinity | |
| JP3915217B2 (en) | Organic waste treatment equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050121 |
|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A711 Effective date: 20050121 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20050121 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20070809 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070821 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20071017 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080318 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080519 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20090421 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20090519 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090609 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090622 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120710 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130710 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140710 Year of fee payment: 5 |
|
| LAPS | Cancellation because of no payment of annual fees |