JP2004233031A

JP2004233031A - Underground heat exchanger with hollow tube buried by rotary press-in method and high-efficiency energy system using it

Info

Publication number: JP2004233031A
Application number: JP2003129223A
Authority: JP
Inventors: Yasushi Nakamura; 靖中村; Eiichiro Saeki; 英一郎佐伯; Yoichi Ishibashi; 洋一石橋
Original assignee: Nippon Steel Corp
Current assignee: Nippon Steel Corp
Priority date: 2002-12-05
Filing date: 2003-05-07
Publication date: 2004-08-19

Abstract

【課題】従来方式の地中熱交換器と比べて著しく工程が短縮でき、建設コストを大幅に抑制できる地中熱交換器とそれを利用した高効率エネルギーシステムを提供する。
【解決手段】下端部に回転羽根２が取り付けられた中空管体１に回転力と下向きの力を付加して回転圧入することで前記中空管体１が埋設され、前記中空管体１内の下端部または中間部には底蓋３が設けられて前記中空管体１の内部が密閉されており、前記中空管体１の内部空間を利用して構築されたことを特徴とする地中熱交換器とそれを利用した高効率エネルギーシステムである。
【選択図】図１[PROBLEMS] To provide an underground heat exchanger capable of significantly reducing the number of steps compared to a conventional underground heat exchanger and greatly reducing construction costs, and a high-efficiency energy system using the same.
The hollow tube is embedded by applying a rotational force and a downward force to the hollow tube with a rotating blade attached to a lower end thereof and rotationally press-fitting the hollow tube. A bottom lid 3 is provided at a lower end or an intermediate portion in the inside 1, the inside of the hollow tube 1 is sealed, and the hollow tube 1 is constructed using the internal space of the hollow tube 1. Underground heat exchanger and high efficiency energy system using it.
[Selection diagram] Fig. 1

Description

【０００１】
【発明の属する技術分野】
本発明は、大地が有する安定した温度を熱源として採放熱して利用する地中熱源方式や、大地の大きな熱容量を利用して土壌に蓄熱を行なう地中蓄熱方式等の地中熱利用システムにおいて、大地と熱利用側の熱授受に用いられる地中熱交換器に関する。
【０００２】
【従来の技術】
大地が有する安定した温度を熱源として採放熱して利用する地中熱源方式や、大地の大きな熱容量を利用して土壌に蓄熱を行なう地中蓄熱方式等の地中熱利用システムは、空調や融雪等に用いられるエネルギーの消費量を削減する方法の１つとして非常に有効である。このように地中熱を利用する場合において、大地と熱利用側との熱授受に用いられる地中熱交換器は、▲１▼Ｕ字管方式や、▲２▼鋼管井戸方式（二重管方式）によるものが一般的である［非特許文献１および非特許文献２参照］。
【０００３】
非特許文献３にも記載されているように、上記▲１▼のＵ字管方式による地中熱交換器は以下の工程で形成される。まず予め地中に孔を掘削し、仮ケーシング３８を挿入して孔の側壁を維持する［図２０（ａ）参照］。次に、この仮ケーシング３８内に送水直管および還水直管の下端部を連結してなるＵ字管２６を１組（１往復分）または２組（２往復分）挿入する［図２０（ｂ）参照］。そして、仮ケーシング３８を引き抜きつつ、孔とＵ字管との間隙にモルタル、グラウト等を充填して埋め戻して設置が完了する［図２０（ｃ），（ｄ）参照］。なお、孔壁維持のためには、仮ケーシング挿入ではなく泥水を用いる場合もある。
【０００４】
また非特許文献４にも記載されているように、上記▲２▼の二重管方式による地中熱交換器は、予め地中に孔を掘削し、この孔内に内挿管を挿入した後、孔と内挿管との間隙にモルタル、グラウト等を充填して埋め戻し、内挿管の内部に送水管および還水管の少なくとも一方を設置することで形成される。
【０００５】
上記▲１▼、▲２▼の地中熱交換器はいずれもエネルギー消費が少ない点で優れている。しかし、いずれの方式による場合も掘削、管挿入、埋め戻し、と工程が多く、このうち掘削費は特に高額である。さらに、孔壁維持のための泥水や仮ケーシングの使用、廃土処理の問題などから設置にかかる建設コストが高くなるため、現在は幅広い普及が阻害されている状況である［非特許文献２および非特許文献５参照］。
【０００６】
ここで地中熱利用システムにおいて、ＰＨＣ製基礎杭を二重管方式地中熱交換器に兼用することで建設コストの低減を図らんとする事例も見られる。しかし、コンクリートのひび割れによる熱源水や不凍液の漏洩が生じる点で改善の余地が多い。一方、水密性に優れる鋼管製の打撃杭については、管内部に土壌が侵入してくることから地中熱交換器との兼用は困難である［非特許文献５参照］。
【０００７】
【非特許文献１】
遠藤，「蓄熱工学Ｉ［基礎編］，第４章地中蓄熱」，森北出版株式会社，１９９５年１２月，１０１〜１０３Ｐ
【非特許文献２】
濱田他，「垂直埋設Ｕ字管を用いた地中蓄熱型冷暖房システムの実験と解析」，空気調和・衛生工学会論文集，Ｎｏ．６１，１９９６年４月，４６〜４７Ｐ
【非特許文献３】
落藤他，「深部地盤直接蓄熱システムに関する調査研究報告書」，財団法人エンジニアリング振興協会地下開発利用研究センター，平成１１年３月，４６〜４７Ｐ
【非特許文献４】
長野，「特集クリーンエネルギーを目指して８．地熱ヒートポンプ」，冷凍，社団法人日本冷凍空調学会，２００１年１２月号第７６巻第８９０号，８Ｐ
【非特許文献５】
宮本他，「地中熱融雪Ｓのコスト削減等福井県雪対策班，省エネ化も」，週間エネルギー通信，エンジニアリングニュース社，第９７６号平成１４年８月５日（月）発行，１７Ｐ
【０００８】
【発明が解決しようとする課題】
本発明は上記従来技術の欠点を除くためにされたものであり、その目的は地中熱交換器の埋設・据付に多工程を要する従来方式に比べて、非常に少ない工程で行なうことができ、かつ廃土処理も不要な地中熱交換器を提供することである。
【０００９】
本発明の他の目的は、孔の掘削時における優れた貫入性と掘削効率の確保を可能とし、地中熱交換器の設置にかかる建設費を大幅に低減できる地中熱交換器を提供することである。
【００１０】
また本発明の他の目的は、建物の基礎杭としての回転圧入鋼管杭において、管内部の土壌の侵入を抑制することで、水密性の高い鋼管杭を地中熱交換器に兼用可能にすることである。
【００１１】
【課題を解決するための手段】
（１）第１の発明は、下端部に回転羽根２が取り付けられた中空管体１に回転力と下向きの力を付加して回転圧入し、埋設された前記中空管体１の内部空間を利用して構築したことを特徴とする地中熱交換器である。
（２）第２の発明は、第１の発明において、中空管体１が鋼管で形成されており、前記中空管体が建物を支持する基礎杭としての回転圧入鋼管杭２２を兼用することを特徴とする。
（３）第３の発明は、第１または第２の発明において、回転羽根２が螺旋状羽根であって、回転羽根２の始端切断面６と終端切断面８との開き角度９が１０度から９０度に設定されていることを特徴とする。
（４）第４の発明は、第１から第３の発明において、中空管体１の管内径以下の直径に設定された開端穴１０が回転羽根２の中心部に設けられていることを特徴とする。
（５）第５の発明は、第１から第４の発明において、中空管体１内の下端部または中間部に底蓋３が設けられて前記中空管体１の内部が密閉されていることを特徴とする。
（６）第６の発明は、第１から第５の発明において、予め底蓋３が内部に固着されている中空管体１が回転圧入で埋設されていることを特徴とする。
（７）第７の発明は、第６の発明において、内部に予め取り付けられた底蓋３または底蓋３より下側の中空管体１側壁部に圧力逃がし穴１４が開口されていることを特徴とする。
（８）第８の発明は、第１から第５の発明において、内周の底蓋形成位置に予め突起物が取り付けられた中空管体１が回転圧入で埋設され、前記中空管体１に内接する落し蓋２１を前記中空管体１の埋設・据付後に前記中空管体１内部に投下し、前記中空管体１の内周と前記落し蓋２１とが固着されて底蓋３が形成されてなることを特徴とする。
（９）第９の発明は、第１から第５の発明において、内周の底蓋形成位置に予め突起物が取り付けられた中空管体１が回転圧入で埋設され、前記中空管体１の埋設・据付後に中空管体１内の底蓋形成位置に経時性硬化材を充填して底蓋３が形成されてなることを特徴とする。
（１０）第１０の発明は、第１から第５の発明において、内周の底蓋形成位置に予め突起物が取り付けられた中空管体１が回転圧入で埋設され、前記中空管体１に内接する落し蓋２１を前記中空管体１の埋設・据付後に前記中空管体１内部に投下し、前記落し蓋２１の上側に経時性硬化材を充填して底蓋３が形成されてなることを特徴とする。
（１１）第１１の発明は、第１から第１０の発明において、中空管体１の内面および外面の少なくとも一方が、防食被覆されていることを特徴とする。
（１２）第１２の発明は、第１から第１１の発明において、中空管体１の外面に熱交換を促進させるフィン１ａを取り付けたことを特徴とする。
（１３）第１３の発明は、第１から第１２の発明において、送水管４および還水管５の少なくとも一方が中空管体１の内側に設置されて前記中空管体１内部には熱媒が循環可能であって、周囲土壌より採熱または放熱ができるように構成されたことを特徴とする。
（１４）第１４の発明は、第１から第１２の発明において、中空管体１の内径よりも小径であって、その先端および頂部が閉塞されてなる外管２３ｂと、前記外管２３ｂの内側に配置されて、先端部近傍で外管２３ｂ外部と連通してなる内管２３ｃとで構成され、かつ前記外管２３ｂおよび前記内管２３ｃの間には空気または断熱材を密封して断熱層２５ａが形成された内挿二重管２３ａが中空管体１の内側に設置され、前記内挿二重管２３ａの内管２３ｃを送水管４および還水管５のいずれか一方として利用し、前記中空管体１と前記内挿二重管２３ａとの間に送水管および還水管の他方を設置することで熱媒が循環可能であって、周囲土壌より採熱または放熱ができるように構成されたことを特徴とする。
（１５）第１５の発明は、第１から第１２の発明において、中空管体１の内径よりも小径でかつ先端が閉塞されている内挿管２３が前記中空管体１の内側に配置され、前記中空管体１と前記内挿管２３との間隙には水またはモルタル、グラウト等の充填材２５が充填されており、送水管４および還水管５の少なくとも一方が前記内挿管２３の内側に設置されて前記内挿管２３内部には熱媒が循環可能であって、周囲土壌より採熱または放熱ができるように構成されたことを特徴とする。
（１６）第１６の発明は、第１から第１２の発明において、熱媒を循環可能なＵ字形内挿管２６が中空管体１の内側に１組以上挿入され、前記中空管体１と前記Ｕ字形内挿管２６との間隙には水またはモルタル、グラウト等の充填材２５が充填されており、周囲土壌より採熱または放熱ができるように構成されたことを特徴とする。
（１７）第１７の発明は、第１４の発明において、複数の中空管体を継ぎ足して構成された地中熱交換器であって、先端部の羽根付中空管体２７には、中空管体の内径よりも小径であって、その先端が閉塞されてなる外管２３ｂと、前記外管２３ｂの内側に配置されて、先端部近傍で外管２３ｂ外部と連通してなる内管２３ｃとからなる内挿二重管２３ａが配置されており、前記羽根付中空管体２７を所定位置まで回転圧入した後に、継手２９によって前記外管２３ｂおよび前記内管２３ｃを各々接続延長し、前記羽根付中空管体２７と継ぎ足し中空管体２８とを必要本数だけ順次接続することで必要長さを確保した上で、前記外管２３ｂおよび前記内管２３ｃの間に空気または断熱材を密封して断熱層２５ａを形成したことを特徴とする。
（１８）第１８の発明は、第１５の発明において、複数の中空管体を継ぎ足して構成された地中熱交換器であって、先端部の羽根付中空管体２７には、前記羽根付中空管体２７の内径よりも小径でかつ先端が閉塞されている内挿管２３が配置されており、前記羽根付中空管体２７を所定位置まで回転圧入した後に、継手２９によって内挿管２３を延長した上で前記羽根付中空管体２７と継ぎ足し中空管体２８とを必要本数だけ順次接続することで必要長さを確保したことを特徴とする。
（１９）第１９の発明は、第１６の発明において、複数の中空管体を継ぎ足して構成された地中熱交換器であって、先端部の羽根付中空管体２７には、Ｕ字形内挿管２６が１組以上挿入されており、前記羽根付中空管体２７を所定位置まで回転圧入した後に、継手２９によって各内挿管を延長した上で前記羽根付中空管体２７と継ぎ足し中空管体２８とを必要本数だけ順次接続することで必要長さを確保したことを特徴とする。
（２０）第２０の発明は、第１から第４の発明において、底蓋３を有しない中空管体１を回転圧入によって埋設し、前記中空管体１内部の土壌中に熱媒を循環可能なＵ字形内挿管２６を圧入し、前記中空管体１内部の土壌が侵入していない前記Ｕ字形内挿管２６と前記中空管体１との間隙には、水またはモルタル、グラウト等の充填材２５が充填されており、周囲土壌より採熱または放熱ができるように構成されたことを特徴とする。
（２１）第２１の発明は、下端に回転羽根２を備えた掘削蓋３１が中空管体１の下端に係合され、前記中空管体１の内側にＵ字形内挿管２６が１組以上挿入され、前記Ｕ字形内挿管２６の折返部分は前記掘削蓋３１に連結されており、前記掘削蓋３１が係合された状態の前記中空管体１を回転圧入で埋設した後、前記中空管体１と前記掘削蓋３１との係合を解除して前記中空管体のみを引き抜き、生じた掘削孔と前記Ｕ字形内挿管２６との空隙に水またはモルタル、グラウト等の充填材２５を充填し、前記Ｕ字形内挿管２６の内部に熱媒を循環して周囲土壌より採熱または放熱ができるように構成されたことを特徴とする地中熱交換器である。
（２２）第２２の発明は、第１〜第２１の発明のいずれかの地中熱交換器とヒートポンプを連結し、前記ヒートポンプと空調機や融雪パイプ等の負荷処理設備を連結し、前記ヒートポンプと負荷処理設備との間に必要に応じて蓄熱槽を設置し、ヒートポンプにて製造した冷熱または温熱を冷房、暖房、融雪のいずれか一つ以上の熱源として使用することを特徴とする高効率エネルギーシステムである。
（２３）第２３の発明は、第１〜第２１の発明のいずれかの地中熱交換器とヒートポンプを連結し、前記ヒートポンプと貯湯槽を連結し、貯湯槽内の水を昇温さらに温度保持し、ヒートポンプにて製造した温熱を給湯用途の熱源として使用することを特徴とする高効率エネルギーシステムである。
（２４）第２４の発明は、第１〜第２１の発明のいずれかの地中熱交換器と空調機や融雪パイプ等の負荷処理設備を連結し、前記地中熱交換器と負荷処理設備との間に必要に応じて蓄熱槽を設置し、前記地中熱交換器内の地温水を循環ポンプにて負荷処理設備に送水することにより冷房、暖房、融雪のいずれか一つ以上の用途に直接利用することを特徴とする高効率エネルギーシステム。
【００１２】
【発明の実施の形態】
＜第１実施形態＞
以下、本発明の第１実施形態の地中熱交換器について、図面を参照しつつ説明する。図１に示すように、第１実施形態の地中熱交換器は、下端部に回転羽根２が取り付けられた中空管体１を回転圧入して埋設し、中空管体１の底蓋３から上方の内部空間に送水管４および還水管５を設置して構築される。
【００１３】
図２に第１実施形態に用いられる中空管体１を示す。この中空管体１が単管で必要熱交換長さに満たない場合には、現場での円周溶接等によって継ぎ足すことで必要熱交換長さを確保する。なお、中空管体１の材質は鋼管に限定されることなく、プラスチック等の樹脂系材料で中空管体１が形成されていてもよい。さらに、中空管体１に外面防食が必要な場合にはポリエチレンやウレタン等で外面被覆を施してもよく、内面防食が必要な場合には硬質塩化ビニルやエポキシ等で内面被覆を施してもよい。
【００１４】
図２（ａ）に示すように、中空管体１の下端は螺旋状に切り欠かれており、この螺旋状切り欠きの始端部と終端部とは段差部分を介して接続されている。そして、螺旋状に切り欠かれた中空管体１の下端面に沿って、回転羽根２が中空管体１に対して同心状に固定されている。
【００１５】
回転羽根２は、図３に示すように円盤状（リング状）の鋼板を半径方向に一部切欠いて形成されており、回転羽根２の始端切断面６には掘削刃７が溶接により固着されている。回転羽根２はその始端切断面６から徐々に中空管体１の下端部から離れながら螺旋状に上昇し、終端切断面８までほぼ１周程度周回するように形成されている。
【００１６】
回転羽根２の始端切断面６と終端切断面８との開き角度９は、図３の例では４５度程度であるが、１０度から９０度の範囲で設定することができる。なお回転羽根２を延長して開き角度９を０度の位置にした場合には、破線で示す仮想終端切断面８ａと始端切断面６とが平行となる。
【００１７】
また回転羽根２の中心部には開端穴１０が開口されている。図２、図３の例では開端穴１０の直径Ｄが中空管体１の内径の０．６倍程度に設定されているが、本発明の開端穴１０の直径は中空管体１の内径以下であればいかなる直径であってもよく、また回転羽根２に開端穴１０を設けなくともよい。
【００１８】
上記のような開き角度９、開端穴１０を備えた回転羽根２は、中空管体１の優れた貫入性を確保し、施工効率向上によるコストの低減に寄与する。また、上記形状の回転羽根２は、管内部への土壌の侵入を管直径の１．５倍程度から管体長さの半分程度までの間に調節することができ、中空管体１の内部空間の有効利用が可能となる。
【００１９】
また中空管体１の内部には底蓋３が設置されており、土壌１１の侵入する中空管体１下部と、地中熱交換器に利用される中空管体１上部とが底蓋３によって区画されている。この底蓋３は回転圧入前に中空管体１内に予め形成されていてもよく、回転圧入後に中空管体１内に事後的に形成してもよい。
【００２０】
図４は底蓋３の取付態様の一例を示したものである。この例では、中空管体１内周の底蓋形成位置に予め突起物として輪状アングル１２を溶接し、この輪状アングル１２の上から落し蓋２１を溶接固定して底蓋３を形成している。なお、輪状アングル１２には必要に応じて補強スチフナを取り付けてもよい。
【００２１】
図４の例において、軟弱地盤等で貫入抵抗が大きくない場合には、予め底蓋３を輪状アングル１２に溶接して底蓋３の取り付けを完了した状態で、中空管体１の回転圧入施工をすることも可能である。この場合、図５に示すように底蓋３より下方の中空管体１下部に土壌１１が適度に侵入して、中空管体１下部に残る空気の圧縮による空気ばね効果が発揮されることで、硬い地層に達すると管内部に土壌１１がさらに侵入して、硬い土壌への貫入性が向上できる場合もある。
【００２２】
一方、地盤の貫入抵抗が大きく、予め底蓋３を取り付けて中空管体１下部を密閉しておくことが困難な場合には、輪状アングル１２のみ先付けした状態で中空管体１を回転圧入した後に、輪状アングル１２に底蓋３を溶接してもよい。
【００２３】
図６の例は、予め中空管体１内周に底蓋３を取り付ける一方で、中空管体１下部の圧力逃がし穴１４を設けて中空管体１下部に土壌１１を侵入し易くし、貫入抵抗を減少させて回転圧入する態様である。図６（ａ），（ｂ）は、底蓋３に圧力逃がし穴１４を設け、中空管体１の回転圧入後に圧力逃がし穴１４をプレート１５で塞ぐことで底蓋３の形成を完了する例である。また図６（ｃ）は圧力逃がし穴１４を底蓋３直下の中空管体１側壁部に開口した例である。この場合には回転圧入後に圧力逃がし穴１４を塞ぐ必要はない。
【００２４】
また、回転圧入後における中空管体１での火気使用を避けたい場合には、以下の種々の方法により事後的な底蓋３の形成が可能である。
【００２５】
図７は、中空管体１内部に土壌１１がある程度侵入してくる場合において底蓋３を回転圧入後に形成する態様の一例である。図７の例では、予め中空管体１内周の土壌侵入位置上部（底蓋形成位置）にコンクリート定着用の輪状鉄筋１６を溶接しておく。次に中空管体の回転圧入後にコンクリート１７を流し込み、さらに防水目地を中空管体との取り合い部に取ったシンダーコンクリート１８を打設する。そして目地部をシール１９した後に塗膜防水２０を行い底蓋３を形成する。なお、底蓋形成位置より地下水位が浅い場合でも、水中コンクリートを打設することにより底蓋３の形成が可能である。
【００２６】
また図８は、中空管体内部に土壌１１があまり侵入してこない場合において底蓋３を回転圧入後に形成する態様の一例である。図８の例では、予め中空管体１内周の土壌侵入位置上部（底蓋形成位置）に輪状アングル１２を溶接しておく。次に中空管体１の回転圧入後に、中空管体１に内接する落し蓋２１を投下した上でシンダーコンクリート１８を打設する。以下、図７の上記例と同様の工程で底蓋３が形成される。
【００２７】
そして中空管体１を回転圧入した後に、中空管体１の内部に送水管４および還水管５を設置して第１実施形態の地中熱交換器が完成する。この第１実施形態の地中熱交換器は、中空管体１の内部空間を熱媒の循環流路として直接使用する構成であって、周囲土壌より採熱または放熱ができるようになっている。
【００２８】
また図９は第１実施形態の地中熱交換器における送水管４および還水管５の配置例である。中空管体１が小口径の場合には、図９（ａ）に示すように送水管４および還水管５のいずれか一方を内挿する二重管方式となる（図示例では送水管４が内挿されている）。また中空管体１の口径が大きい場合には、図９（ｂ）に示すように送水管４および還水管５の両方を内挿する鋼管井戸方式となる。
【００２９】
第１実施形態の地中熱交換器では、中空管体１の回転圧入後に中空管体１の内部に送水管４および還水管５の少なくとも一方を設置するだけで施工が完了するため、従来方式の地中熱交換器と比べて著しく工程が短縮でき、飛躍的なコスト削減が可能となる。
【００３０】
＜第２実施形態＞
図１０は第２実施形態の地中熱交換器を示した図である。なお、以下の実施形態で第１実施形態と同一の構成には同一符号を付して重複説明を省略する。
【００３１】
第２実施形態は、建物を支持する基礎杭としての回転圧入鋼管杭２２を地中に回転圧入して埋設し、回転圧入鋼管杭２２の先端付近または中間部に底蓋３を形成して密閉し、その回転圧入鋼管杭２２の内部空間を利用して構築される地中熱交換器である。第２実施形態の地中熱交換器は、建物の支持に元来必要である基礎杭を熱交換器として兼用するため、熱交換器単独の埋設設置コストは不要となり、より一層のコスト削減が可能になる。なお、送水管４および還水管５の取り出し方法としては、図１０（ａ）に示すように、通常通り、回転圧入鋼管杭２２の頂部にフーチング２２ａを被せる取り合いとし、送水管４および還水管５を水平取り出しする方法や、回転圧入鋼管杭２２頂部のフーチング取合部外周に突起物を取り付けて、杭からフーチングに支持力を伝達することとし、送水管４および還水管５を垂直に取り出す方法、そしてこれらを併用した方法が考えられる。
【００３２】
＜第３実施形態＞
図１１は第３実施形態の地中熱交換器を示した図である。第３実施形態では中空管体１の外周に熱交換促進用のフィン１ａが取り付けてある。フィン１ａの形状は中空管体１の回転圧入に支障のない形状であればよく、例えば掘削用回転羽根を上方に延長してなる小径螺旋型フィンなどが考えられる。なお、図１１では中空管体１の全長にわたってフィン１ａが設けられているが、フィン１ａが熱交換促進に効果的であるのは地下水が存在する場合なので、実際には帯水層などの地下水が存在する地層部分をカバーできるようにフィン１ａを設ければよい。
【００３３】
＜第４実施形態＞
図１２は第４実施形態の地中熱交換器を示した図である。第４実施形態では中空管体１の内側に内挿二重管２３ａを挿入し、内管２３ｃの内部および外管２３ｂの外側に熱媒を循環させて、周囲土壌より採熱または放熱ができるように構成されている。この第４実施形態は、地中熱交換器内の保有熱媒量を少なくできる点で有利である。例えば、基礎杭などの大口径の中空管体を地中熱交換器として用い、かつ寒冷地において熱媒に高価な不凍液を用いなければならない場合には、使用する不凍液の量を減少できるのでコスト面で有利となる。
【００３４】
第４実施形態に用いられる内挿二重管２３ａは、中空管体１の内径よりも小径の外管２３ｂと、この外管２３ｂの内側に配置される内管２３ｃで構成されている。外管２３ｂの先端はキャップ２４により閉塞されており、外管２３ｂの頂部は内管２３ｃが挿通する穴あきキャップ２４ａにより閉塞されている。また、外管２３ｂの先端部近傍には、内管２３ｃと連通してなる開口が設けられている。そして、内挿二重管２３ａにおける外管２３ｂおよび内管２３ｃの間には、空気または断熱材が密封されて断熱層２５ａが形成されている。
【００３５】
第４実施形態の地中熱交換器では、中空管体１の内側に内挿二重管２３ａが配置され、かつ中空管体１と内挿二重管２３ａとの間に還水管５が配置されている。そして、内挿二重管２３ａの内管２３ｃから送られた熱媒は、外管２３ｂの開口部を経て、中空管体１と内挿二重管２３ａとの間から還水管５へ循環するように構成されている。なお、第４実施形態では内挿二重管２３ａの内管２３ｃが送水管となる例を示したが、その逆に内管２３ｃを還水管として、中空管体１と内挿二重管２３ａとの間に送水管４を配置する構成としてもよい［図示を省略する。］
【００３６】
＜第５実施形態＞
図１３は第５実施形態の地中熱交換器を示した図である。第５実施形態では中空管体１の内側に内挿管２３を配置し、内挿管２３内部に熱媒を循環させることで周囲土壌より採熱または放熱ができるように構成されている。
【００３７】
第５実施形態の内挿管２３はその外径が中空管体１の内径よりも小さく設定されており、中空管体１の内側に内挿管２３が挿入配置されている。内挿管２３の先端はキャップ２４などによって閉塞されている。中空管体１と内挿管２３との間隙には水またはモルタル、グラウト等の充填材２５が充填されている。そして、内挿管２３の内側には送水管４が配置され、かつ中空管体１からはみ出した内挿管２３の上端部は還水管５と接続されており、水またはその他の熱媒が内挿管２３の内部を循環するように構成されている。
【００３８】
＜第６実施形態＞
図１４は第６実施形態の地中熱交換器を示した図である。第６実施形態では送水直管および還水直管の下端部を連結して構成された１組（１往復分）のＵ字管２６が中空管体１の内側に挿入されている。中空管体１とＵ字管２６との間隙には水またはモルタル、グラウト等の充填材２５が充填されており、水またはその他の熱媒をＵ字管２６の内部に循環させることで周囲土壌より採熱または放熱ができるように構成されている。なお、図１４の例では中空管体１の内側に挿入されたＵ字管２６は１組（１往復分）であるが、２組（２往復分）のＵ字管を配置する構成でもよい［図示を省略する］。
【００３９】
＜第７実施形態＞
図１５は第７実施形態の地中熱交換器を示した図である。第７実施形態は第４実施形態の変形例であって、中空管体１および内挿二重管２３ａを継ぎ足して地中熱交換器を延長し、必要熱交換長さを確保した例である。
【００４０】
第７実施形態の地中熱交換器の設置作業では、まず先端部の羽根付中空管体２７の内側に内挿二重管２３ａの先端部を挿入しておく。内挿二重管２３ａの羽根付中空管体２７への固定は、羽根付中空管体２７の底蓋３に取付けたキャップ２４に内挿二重管２３ａを嵌め込むことで行う。
【００４１】
次に、羽根付中空管体２７を所定位置まで回転圧入し、継ぎ足し用の外管２３ｂおよび内管２３ｃを吊り込んで、内挿二重管２３ａを延長する。外管２３ｂおよび内管２３ｃの接合は、水密性、可撓性および伸縮性に優れた継手２９によって行う。
【００４２】
さらに羽根付中空管体２７と継ぎ足し用中空管体２８とを現場円周溶接等により接合し、接合完了後に一体化した中空管体１を回転圧入する。必要に応じて上記の継ぎ足し作業を繰り返すことで、所望の長さまで地中熱交換器を延長することができる。また、中空管体１の回転圧入完了後に外管２３ｂの頂部を穴あきキャップ２４ａで閉塞して、外管２３ｂおよび内管２３ｃの間に断熱層２５ａを形成する。そして、中空管体１と内挿二重管２３ａとの間隙に還水管５を配置して地中熱交換器が完成する。
【００４３】
なお、第７実施形態における設置作業はあくまで１例であって、図示の例に限定されることはない。例えば、羽根付中空管体２７を継ぎ足し中空管体２８によって延長して必要長さを埋設した後に、吊り込み固定冶具を用いて内挿二重管２３ａを継手２９で延長しながら、中空管体１内に落しこんでいってもよい［図示を省略する］。
【００４４】
＜第８実施形態＞
図１６は第８実施形態の地中熱交換器を示した図である。第８実施形態は第５実施形態の変形例であって、中空管体１および内挿管２３を継ぎ足して地中熱交換器を延長し、必要熱交換長さを確保した例である。
【００４５】
第８実施形態の地中熱交換器の設置作業では、まず先端部の羽根付中空管体２７の内側に、先端が閉塞された小径の内挿管２３を挿入する。この羽根付中空管体２７と内挿管２３との間隙にはモルタル、グラウト等の充填材２５が充填されており、内挿管２３が固定されている。
【００４６】
次に、羽根付中空管体２７を所定位置まで回転圧入し、継ぎ足し用中空管体２８を吊り込んで、羽根付中空管体２７と継ぎ足し用中空管体２８とを接合する。継ぎ足し用の中空管体２８には内挿管２３が挿入され、かつ中空管体２８と内挿管２３との間隙にはモルタル、グラウト等の充填材２５が充填されている。そして、内挿管２３同士の接合は、水密性、可撓性および伸縮性に優れた継手２９によって行い、羽根付中空管体２７と継ぎ足し用中空管体２８との接合は、現場円周溶接等により行なわれる。なお、接合部に充填材２５の注入孔を予め設けておき、羽根付中空管体２７と継ぎ足し用中空管体２８との接合後に継手２９の空隙部に充填材２５を注入して、注入孔を塞ぐのがより好ましい。
【００４７】
上記の羽根付中空管２７体と継ぎ足し用中空管体２８との接合が完了した後、一体化した中空管体１を回転圧入する。必要に応じて上記の継ぎ足し作業を繰り返すことで、所望の長さまで地中熱交換器を延長することができる。そして、中空管体１の回転圧入完了後に内挿管２３の内側に送水管４を配置して地中熱交換器が完成する。
【００４８】
なお、第８実施形態における設置作業はあくまで１例であって、図示の例に限定されることはない。例えば、継ぎ足し中空管体２８に予め内挿管２３を固定することなく、継ぎ足し中空管体２８と内挿管２３とを同時に吊り込んで各々接合し、必要な長さを埋設した後に充填材２５を充填してもよい。また、内挿管２３の固定を冶具によって行い、中空管体１の埋設が完了した後で充填材２５を充填してもよい［ともに図示を省略する］。
【００４９】
＜第９実施形態＞
図１７は第９実施形態の地中熱交換器を示した図である。第９実施形態は第６実施形態の変形例であって、中空管体１およびＵ字管２６内挿管２３を継ぎ足して地中熱交換器を延長する例である。この第９実施形態は、羽根付中空管体２７に配置されたＵ字管２６に、継ぎ足し中空管体２８内に配置された送水直管および還水直管を継ぎ足す点で第８実施形態と異なる。なお、図１７の例では中空管体１の内側に挿入されたＵ字管２６は１組（１往復分）であるが、２組（２往復分）のＵ字管を配置する構成でもよい。
【００５０】
＜第１０実施形態＞
図１８は第１０実施形態の地中熱交換器を示した図である。第１０実施形態は、底蓋を有しない中空管体１を回転圧入によって埋設した後に、中空管体１の内部に充填された土壌１１中にＵ字管２６を圧入する地中熱交換器の設置例である。第１０実施形態は、底蓋を設けて中空管体１の内部空間を予め確保しなくとも、土壌１１を除去することなくＵ字管２６を土壌１１中に圧入可能と判断される場合（例えば軟弱地盤等の場合）に用いられる。Ｕ字管２６を土壌１１に圧入した後において、中空管体１内部の土壌１１が侵入していない間隙部分には、モルタル、グラウト等の充填材２５が充填されており、周囲土壌より採熱または放熱ができるように構成されている。
【００５１】
＜第１１実施形態＞
図１９は第７実施形態の地中熱交換器を示した図である。第１１実施形態では、Ｕ字管２６を内挿した中空管体１を回転圧入した後に、管体３０のみを引き抜いて地中にＵ字管２６を配置して地中熱交換器を形成する。
【００５２】
第１１実施形態の施工に用いられる中空管体１は、管体３０の先端部に取り付けられる掘削蓋３１と複数の管体３０とをジョイントで機械的に連結することで構成されている。なお、管体３０と掘削蓋３１とのジョイントには、例えば、掘削蓋３１の内側に挿入される管体３０の係合部分に鉤状切り込みを設け、掘削蓋３１の内周に突起を設けて、鉤状切り込みと突起とを係合・解除するものなど、種々のジョイントが適用できる［図示を省略する］。
【００５３】
また掘削蓋３１の下端には回転羽根２が設けられている。さらに掘削蓋３１の内側上面にはスイベルジョイント３２が設けられており、このスイベルジョイント３２によってＵ字管２６下端の折返部分が掘削蓋３１に連結されている。
【００５４】
第１１実施形態の地中熱交換器の施工は、以下の工程で行なわれる。
▲１▼ まず、管体３０の先端に掘削蓋３１をジョイントで連結して中空管体１を構成し、中空管体１の内側にＵ字管２６を配置する。またＵ字管２６の折返部分は掘削蓋３１に連結する。
▲２▼ 次に中空管体１を地中に回転圧入する。なお、中空管体１の長さが不足する場合には管体３０をジョイントで連結して継ぎ足しながら回転圧入を行なう［図１９（ａ）参照］。
▲３▼ 中空管体１を所望の長さまで回転圧入した後、管体３０と掘削蓋３１とのジョイントを解除して、掘削孔から管体３０のみを引き抜く［図１９（ｂ）参照］。これにより、掘削孔の内部には掘削蓋３１とＵ字管２６が残される［図１９（ｃ）参照］。
▲４▼ そして、掘削孔とＵ字管２６との空隙に水またはモルタル、グラウト等の充填材２５を充填することで地中熱交換器が完成する［図１９（ｄ）参照］。
【００５５】
図２１は、本発明の地中熱交換器を用いた高効率エネルギーシステムの一実施形態を示すものである。この高効率エネルギーシステムでは、地中に設置された基礎杭兼用地中熱交換器４１と専用杭地中熱交換器４２とが、地表の建物４３内に設置したヒートポンプ４４に連結される。空調系統においては、ヒートポンプ４４は、空調機４５と連結され、空調機４５からの冷暖房空気が空調ダクト４６を通して建物４３内の空間に噴出する。また、ヒートポンプ４４は、室内用空調機４７に連結され、これにより室内を冷却・加熱する。図示しているのは、室内用空調機であるファンコイルユニットの例であるが、放熱機や床暖房パイプ等を用いる場合もある。ヒートポンプ４４と空調機４５、室内用空調機４７との間に必要に応じて蓄熱槽４８を設置する。蓄熱槽４８は、ヒートポンプ４４の能力がピーク負荷に満たない時や夜間電力を利用する場合に設置する。給湯系統においては、ヒートポンプ４４と貯湯槽５０を連結し、貯湯槽内の水を昇温さらに温度保持し、ここから安定した給湯温度で給湯栓４９にお湯を供給する。
【００５６】
図２２は、本発明の地中熱交換器を用いた高効率エネルギーシステムの他の実施形態を示すものである。この高効率エネルギーシステムでは、地中に設置された専用杭地中熱交換器４２と道路の路面下に埋設された融雪パイプ５１と熱媒循環ポンプ５２を介して連結したものである。
【００５７】
【発明の効果】
本発明の地中熱交換器は、多工程が必要となる従来方式の地中熱交換器と比べて著しく工程が短縮できる。また、泥水や廃土処理も不要であって、独自の回転羽根形状によって中空管体の貫入性に優れることから、地中熱交換器の設置にかかる建設コストを大幅に抑制できる。
【００５８】
また本発明では、回転羽根形状や底蓋の形成方法によって、水密性の高い鋼管杭の内部空間を熱交換器として兼用することを可能とした。そのため、建物の支持に元来必要である基礎杭を熱交換器として兼用することで、熱交換器単独の埋設設置コストは不要となり、より一層のコスト削減が可能になる。
【００５９】
なお、地中熱利用システムはエネルギー消費の非常に少ない優れたシステムであるが、非常に高い建設費がによって幅広い普及が阻害されているのが現状である。したがって、本発明の上記の効果によりその普及が促進されることが期待できる。
【図面の簡単な説明】
【図１】第１実施形態の地中熱交換器を示した図である。
【図２】第１実施形態に用いられる中空管体を示す図である。
【図３】第１実施形態に用いられる回転羽根を示す図である。
【図４】底蓋の取付態様の一例を示した図である。
【図５】中空管体に予め底蓋を形成した場合の空気ばね効果を説明する図である。
【図６】中空管体の圧力逃がし穴の設置例を示した図である。
【図７】底蓋を回転圧入後に形成する態様の一例を示した図である。
【図８】底蓋を回転圧入後に形成する態様の一例を示した図である。
【図９】第１実施形態の地中熱交換器における送水管および還水管の配置例を示した図である。
【図１０】第２実施形態の地中熱交換器を示した図である。
【図１１】第３実施形態の地中熱交換器を示した図である。
【図１２】第４実施形態の地中熱交換器を示した図である。
【図１３】第５実施形態の地中熱交換器を示した図である。
【図１４】第６実施形態の地中熱交換器を示した図である。
【図１５】第７実施形態の地中熱交換器を示した図である。
【図１６】第８実施形態の地中熱交換器を示した図である。
【図１７】第９実施形態の地中熱交換器を示した図である。
【図１８】第１０実施形態の地中熱交換器を示した図である。
【図１９】第１１実施形態の地中熱交換器を示した図である。
【図２０】従来のＵ字管方式による地中熱交換器の施工工程を示す図である。
【図２１】本発明の地中熱交換器を用いた高効率エネルギーシステムの一実施形態を示す図である。
【図２２】本発明の地中熱交換器を用いた高効率エネルギーシステムの他の実施形態を示す図である。
【符号の説明】
１中空管体
１ａフィン
２回転羽根
３底蓋
４送水管
５還水管
６始端切断面
７掘削刃
８終端切断面
８ａ仮想終端切断面
９開き角度
１０開端穴
１１土壌
１２輪状アングル
１３溶接部
１４圧力逃がし穴
１５プレート
１６輪状鉄筋
１７コンクリート
１８シンダーコンクリート
１９シール
２０塗膜防水
２１落し蓋
２２回転圧入鋼管杭
２２ａフーチング
２３内挿管
２３ａ内挿二重管
２３ｂ外管
２３ｃ内管
２４キャップ
２４ａ穴あきキャップ
２５充填材
２５ａ断熱層
２６Ｕ字管（Ｕ字形内挿管）
２７羽根付中空管体
２８継ぎ足し用中空管体
２９継手
３０管体
３１掘削蓋
３２スイベルジョイント
３３地表面
３７中空スクリューオーガ
３８仮ケーシング
４０モルタル
４１基礎杭兼用地中熱交換器
４２専用杭地中熱交換器
４３建物
４４ヒートポンプ
４５空調機
４６空調用ダクト
４７室内用空調機
４８蓄熱槽
４９給水栓
５０貯湯槽
５１融雪パイプ
５２熱媒循環ポンプ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an underground heat utilization system such as an underground heat source system that collects and radiates a stable temperature of the earth as a heat source and uses it, and an underground heat storage system that stores heat in soil using a large heat capacity of the earth. The present invention relates to an underground heat exchanger used for heat transfer between the earth and a heat utilization side.
[0002]
[Prior art]
Underground heat utilization systems such as the underground heat source system, which collects and radiates and uses the stable temperature of the earth as a heat source, and the underground heat storage system, which uses the large heat capacity of the earth to store heat in soil, use air conditioning and snow melting. It is very effective as one of the methods for reducing the consumption of energy used for such purposes. When using underground heat in this way, the underground heat exchanger used for heat exchange between the ground and the heat utilization side is a (1) U-shaped tube system or (2) a steel tube well system (double tube system). (See Non-Patent Document 1 and Non-Patent Document 2).
[0003]
As described in Non-Patent Document 3, the underground heat exchanger based on the U-tube method (1) is formed by the following steps. First, a hole is excavated in the ground in advance, and the temporary casing 38 is inserted to maintain the side wall of the hole (see FIG. 20A). Next, one set (one reciprocation) or two sets (two reciprocations) of the U-shaped pipe 26 connecting the lower ends of the water feed straight pipe and the return water straight pipe are inserted into the temporary casing 38 [FIG. (B)]. Then, while pulling out the temporary casing 38, the gap between the hole and the U-shaped tube is filled with mortar, grout and the like, and the space is backfilled to complete the installation [see FIGS. 20 (c) and (d)]. In order to maintain the hole wall, muddy water may be used instead of inserting the temporary casing.
[0004]
Further, as described in Non-patent Document 4, the underground heat exchanger using the double pipe method described in (2) above excavates a hole in the ground in advance and inserts an intubation tube into the hole. The gap between the hole and the intubation is filled with mortar, grout, or the like, backfilled, and at least one of a water supply pipe and a return water pipe is installed inside the intubation.
[0005]
The above-mentioned underground heat exchangers (1) and (2) are excellent in that they consume little energy. However, all of these methods involve many steps such as excavation, pipe insertion, backfilling, and the excavation cost is particularly high. Furthermore, the use of muddy water and temporary casing for maintaining the pore wall, the problem of waste soil treatment, and the like, increase the construction cost for installation, and currently widespread use is hindered [Non-Patent Document 2 and Non-Patent Document 5].
[0006]
Here, in the underground heat utilization system, there is a case in which the construction cost is reduced by using the PHC foundation pile as the double-pipe underground heat exchanger. However, there is much room for improvement in leakage of heat source water and antifreeze due to cracks in concrete. On the other hand, a steel pipe hammering pile having excellent watertightness is difficult to use as an underground heat exchanger because soil penetrates into the pipe [see Non-Patent Document 5].
[0007]
[Non-patent document 1]
Endo, "Thermal Storage Engineering I [Basic], Chapter 4 Underground Thermal Storage", Morikita Publishing Co., Ltd., December 1995, 101-103P
[Non-patent document 2]
Hamada et al., "Experiment and analysis of underground thermal storage type cooling and heating system using vertical buried U-tube", Transactions of the Society of Air Conditioning and Sanitary Engineers, No. 61, April 1996, 46-47P
[Non-Patent Document 3]
Ochito et al., “Survey and Research Report on Deep Ground Direct Thermal Storage System”, Engineering Promotion Association Underground Development and Utilization Research Center, March 1999, 46-47P
[Non-patent document 4]
Nagano, "Special Issue Aiming at Clean Energy 8. Geothermal Heat Pump", Refrigeration, Japan Refrigeration and Air Conditioning Society, December 2001, Vol. 76, No. 890, 8P
[Non-Patent Document 5]
Miyamoto et al., "Fukui Prefecture Snow Countermeasures Group, Cost Reduction of Underground Snow Melting S, Energy Saving", Weekly Energy Communication, Engineering News, No. 976, Published August 5, 2002 (Mon.), 17P
[0008]
[Problems to be solved by the invention]
The present invention has been made in order to eliminate the above-mentioned disadvantages of the prior art, and the object thereof is that it can be performed in a very small number of steps as compared with the conventional method that requires multiple steps for burying and installing the underground heat exchanger. Another object of the present invention is to provide an underground heat exchanger that does not require waste soil treatment.
[0009]
Another object of the present invention is to provide an underground heat exchanger that can ensure excellent penetration and excavation efficiency when excavating a hole and can greatly reduce the construction cost required for installing an underground heat exchanger. That is.
[0010]
Another object of the present invention is to provide a rotary press-fit steel pipe pile as a foundation pile of a building, by suppressing intrusion of soil inside the pipe, thereby enabling a water-tight steel pipe pile to be used also as an underground heat exchanger. That is.
[0011]
[Means for Solving the Problems]
(1) According to a first aspect of the present invention, the hollow tube 1 having a rotating blade 2 attached to a lower end portion is rotationally press-fitted by applying a rotational force and a downward force to the hollow tube 1 and embedded in the hollow tube 1. This is an underground heat exchanger constructed using space.
(2) In a second aspect, in the first aspect, the hollow pipe 1 is formed of a steel pipe, and the hollow pipe also serves as a rotary press-fit steel pipe pile 22 as a foundation pile for supporting a building. It is characterized by the following.
(3) In the third invention, in the first or second invention, the rotary blade 2 is a spiral blade, and an opening angle 9 between the start end cut surface 6 and the end cut surface 8 of the rotary blade 2 is 10 degrees. From 90 degrees.
(4) According to a fourth aspect of the present invention, in the first to third aspects, the open end hole 10 having a diameter equal to or less than the inner diameter of the hollow tubular body 1 is provided at the center of the rotary blade 2. Features.
(5) In a fifth aspect based on the first to fourth aspects, a bottom lid 3 is provided at a lower end portion or an intermediate portion in the hollow tubular body 1 so that the inside of the hollow tubular body 1 is sealed. It is characterized by having.
(6) A sixth invention is characterized in that, in the first to fifth inventions, the hollow tubular body 1 to which the bottom cover 3 is fixed in advance is buried by rotary press fitting.
(7) According to a seventh aspect of the present invention, in the sixth aspect, the pressure relief hole 14 is opened in the bottom cover 3 previously mounted inside or the side wall portion of the hollow tubular body 1 below the bottom cover 3. It is characterized by.
(8) An eighth aspect of the present invention is based on the first to fifth aspects, wherein the hollow tubular body 1 to which a protrusion is attached in advance at the bottom cover forming position on the inner periphery is buried by rotary press-fitting. 1 is dropped into the hollow tube 1 after the hollow tube 1 is buried and installed, and the inner periphery of the hollow tube 1 and the drop cover 21 are fixed and the bottom cover 3 is fixed. Is formed.
(9) In a ninth aspect, in the first to fifth aspects, the hollow tubular body 1 to which a protrusion is attached in advance at a bottom cover forming position on the inner periphery is buried by rotary press fitting, and the hollow tubular body 1 is provided. 1 is characterized in that a bottom cover 3 is formed by filling the bottom cover forming position in the hollow tubular body 1 with a time-hardening material after the embedding and installation.
(10) In a tenth aspect based on the first to fifth aspects, the hollow tubular body 1 to which a protrusion is attached in advance at a bottom cover forming position on the inner periphery is buried by rotary press fitting, and 1 is dropped into the hollow tubular body 1 after the hollow tubular body 1 is buried and installed, and the lower lid 3 is formed by filling a temporal hardening material on the upper side of the dropped cover 21. It is characterized by becoming.
(11) According to an eleventh aspect, in the first to tenth aspects, at least one of the inner surface and the outer surface of the hollow tubular body 1 is coated with anticorrosion.
(12) A twelfth invention is characterized in that, in the first to eleventh inventions, a fin 1a for promoting heat exchange is attached to the outer surface of the hollow tubular body 1.
(13) A thirteenth invention is the invention according to the first to twelfth inventions, wherein at least one of the water pipe 4 and the return pipe 5 is installed inside the hollow tube 1 and heat is generated inside the hollow tube 1. It is characterized in that the medium can be circulated and heat can be collected or radiated from the surrounding soil.
(14) In a fourteenth aspect, in the first to twelfth aspects, the outer pipe 23b has a diameter smaller than the inner diameter of the hollow tubular body 1 and has a tip and a top closed, and the outer pipe 23b And an inner tube 23c which is disposed near the distal end and communicates with the outside of the outer tube 23b, and air or heat insulating material is sealed between the outer tube 23b and the inner tube 23c. An insertion double pipe 23a on which a heat insulating layer 25a is formed is installed inside the hollow pipe body 1, and the inner pipe 23c of the insertion double pipe 23a is used as one of the water supply pipe 4 and the return water pipe 5. By installing the other of the water pipe and the return pipe between the hollow pipe body 1 and the insertion double pipe 23a, the heat medium can circulate, and heat can be collected or radiated from the surrounding soil. It is characterized by having been constituted as follows.
(15) In a fifteenth aspect based on the first to twelfth aspects, the inner tube 23 having a diameter smaller than the inner diameter of the hollow tube 1 and having a closed end is disposed inside the hollow tube 1. A gap between the hollow tube 1 and the inner tube 23 is filled with a filler 25 such as water or mortar or grout. At least one of the water supply pipe 4 and the return pipe 5 is connected to the inner tube 23. A heat medium can be circulated inside the inner tube 23 so as to be able to collect or radiate heat from surrounding soil.
(16) In a sixteenth aspect based on the first to twelfth aspects, one or more sets of U-shaped inner cannula 26 capable of circulating a heat medium are inserted inside the hollow tubular body 1, The gap between the U-shaped inner tube 26 and the U-shaped inner tube 26 is filled with a filler 25 such as water or mortar or grout, so that heat can be collected or radiated from the surrounding soil.
(17) A seventeenth invention is an underground heat exchanger according to the fourteenth invention, wherein the underground heat exchanger is formed by adding a plurality of hollow pipes. An outer tube 23b having a diameter smaller than the inner diameter of the hollow tube body and having a closed end, and an inner tube disposed inside the outer tube 23b and communicating with the outside of the outer tube 23b near the end. An insertion double pipe 23a consisting of an outer pipe 23b and an inner pipe 23c is connected and extended by a joint 29 after the hollow pipe 27 with wings is rotationally press-fitted to a predetermined position. The required length is ensured by sequentially connecting the required number of hollow pipes 28 with the bladed hollow pipe 27, and air or heat insulation is provided between the outer pipe 23b and the inner pipe 23c. The heat insulating layer 25a is formed by sealing the material.
(18) An eighteenth invention is the underground heat exchanger according to the fifteenth invention, wherein a plurality of hollow pipes are added to each other. An insertion tube 23 having a diameter smaller than the inner diameter of the bladed hollow tube 27 and having a closed end is disposed. After the bladed hollow tube 27 is rotationally press-fitted to a predetermined position, the inner tube 23 is internally connected thereto by a joint 29. The required length is ensured by extending the intubation tube 23 and then connecting the required number of hollow tube members 28 with the bladed hollow tube members 27 in order.
(19) A nineteenth invention is the underground heat exchanger according to the sixteenth invention, wherein a plurality of hollow pipes are added to each other, and the hollow pipe body with blades at the tip end has a U shape. One or more sets of V-shaped intubation tubes 26 are inserted, and after the hollow tube body 27 with blades is rotationally press-fitted to a predetermined position, each intubation is extended by a joint 29, and the hollow tube body 27 with blades is inserted. The required length is secured by sequentially connecting the required number of hollow pipes 28 to the extension pipes.
(20) According to a twentieth aspect, in the first to fourth aspects, the hollow tubular body 1 having no bottom lid 3 is buried by rotary press-fitting, and a heat medium is introduced into the soil inside the hollow tubular body 1. A circulating U-shaped inner tube 26 is press-fitted, and water, mortar, grout or the like is inserted into the gap between the U-shaped inner tube 26 and the hollow tube 1 where the soil inside the hollow tube 1 has not penetrated. Or the like, and is configured to be able to collect or radiate heat from the surrounding soil.
(21) According to the twenty-first aspect, a drilling lid 31 having a rotating blade 2 at a lower end is engaged with a lower end of the hollow tubular body 1, and a set of U-shaped insertion tubes 26 is provided inside the hollow tubular body 1. Inserted above, the folded portion of the U-shaped inner cannula 26 is connected to the excavation lid 31, and after embedding the hollow tubular body 1 in a state where the excavation lid 31 is engaged by rotary press fitting, The engagement between the hollow tube 1 and the excavation lid 31 is released and only the hollow tube is pulled out, and the space between the formed excavation hole and the U-shaped inner tube 26 is filled with water, mortar, grout, or the like. The underground heat exchanger is characterized in that the underground heat exchanger is configured to be filled with a material 25 and circulate a heat medium inside the U-shaped intubation tube 26 so as to collect or radiate heat from surrounding soil.
(22) A twenty-second invention relates to the heat pump, wherein the underground heat exchanger according to any one of the first to twenty-first inventions is connected to a heat pump, and the heat pump is connected to a load processing facility such as an air conditioner or a snow melting pipe. High efficiency characterized by installing a heat storage tank between the equipment and the load processing equipment as needed, and using the cold or hot heat produced by the heat pump as one or more of heat sources for cooling, heating, and snow melting Energy system.
(23) In a twenty-third aspect, the underground heat exchanger according to any one of the first to twenty-first aspects is connected to a heat pump, the heat pump is connected to a hot water tank, and the temperature of the water in the hot water tank is increased. A high-efficiency energy system characterized by holding and using heat generated by a heat pump as a heat source for hot water supply.
(24) A twenty-fourth aspect of the present invention relates to the underground heat exchanger according to any one of the first to twenty-first aspects, wherein the underground heat exchanger is connected to a load processing facility such as an air conditioner or a snow melting pipe. A heat storage tank is installed as necessary between the above and cooling water, heating, and one or more uses of snow melting by sending geothermal water in the underground heat exchanger to a load processing facility by a circulation pump. A high-efficiency energy system that is directly used for
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
<First embodiment>
Hereinafter, an underground heat exchanger according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the underground heat exchanger of the first embodiment embeds a hollow tubular body 1 having a rotating blade 2 attached to a lower end portion by rotary press-fitting and burying the hollow tubular body 1. The water supply pipe 4 and the return water pipe 5 are installed in the internal space above 3 and constructed.
[0013]
FIG. 2 shows a hollow tube 1 used in the first embodiment. If the hollow tube 1 is a single tube and has a length less than the required heat exchange length, the required heat exchange length is secured by adding it by circumferential welding or the like at the site. The material of the hollow tube 1 is not limited to a steel tube, and the hollow tube 1 may be formed of a resin material such as plastic. Further, when external corrosion protection is required for the hollow tubular body 1, the outer surface may be coated with polyethylene, urethane, or the like, and when internal corrosion protection is required, the inner surface may be coated with hard vinyl chloride, epoxy, or the like. Good.
[0014]
As shown in FIG. 2A, the lower end of the hollow tube 1 is spirally cut out, and the start end and the end of the spiral cut are connected via a step. The rotating blades 2 are concentrically fixed to the hollow tubular body 1 along the lower end surface of the hollow tubular body 1 cut in a spiral shape.
[0015]
As shown in FIG. 3, the rotary blade 2 is formed by partially cutting a disk-shaped (ring-shaped) steel plate in a radial direction, and a cutting edge 7 is fixed to a cutting end surface 6 of the rotary blade 2 by welding. ing. The rotary blade 2 is formed so as to spirally move upward from the start end cut surface 6 while gradually moving away from the lower end of the hollow tubular body 1, and to make approximately one turn to the end cut surface 8.
[0016]
The opening angle 9 between the start end cut surface 6 and the end cut surface 8 of the rotary blade 2 is about 45 degrees in the example of FIG. 3, but can be set in the range of 10 degrees to 90 degrees. When the rotating blades 2 are extended to set the opening angle 9 to a position of 0 degrees, the virtual end cut surface 8a and the start end cut surface 6 indicated by broken lines become parallel.
[0017]
An open end hole 10 is opened in the center of the rotary blade 2. In the examples of FIGS. 2 and 3, the diameter D of the open end hole 10 is set to about 0.6 times the inner diameter of the hollow tubular body 1. Any diameter may be used as long as it is equal to or less than the inner diameter, and the open end hole 10 need not be provided in the rotary blade 2.
[0018]
The rotary blade 2 having the opening angle 9 and the open end hole 10 as described above ensures excellent penetration of the hollow tube 1 and contributes to cost reduction by improving construction efficiency. In addition, the rotating blades 2 having the above-described shape can adjust the penetration of soil into the inside of the tube from about 1.5 times the diameter of the pipe to about half the length of the pipe. Effective use of space becomes possible.
[0019]
A bottom cover 3 is provided inside the hollow tube 1 so that a lower portion of the hollow tube 1 in which the soil 11 enters and an upper portion of the hollow tube 1 used for the underground heat exchanger are formed at the bottom. It is partitioned by the lid 3. The bottom cover 3 may be formed beforehand in the hollow tubular body 1 before the rotary press-fitting, or may be formed in the hollow tubular body 1 after the rotary press-fitting.
[0020]
FIG. 4 shows an example of an attachment mode of the bottom cover 3. In this example, the bottom cover 3 is formed by welding a ring-shaped angle 12 as a protrusion in advance to the bottom cover formation position on the inner periphery of the hollow tubular body 1 and dropping and fixing a drop cover 21 from above the ring-shaped angle 12. . Note that a reinforcing stiffener may be attached to the annular angle 12 as necessary.
[0021]
In the example of FIG. 4, when the penetration resistance is not large in a soft ground or the like, the bottom cover 3 is welded to the ring-shaped angle 12 in advance and the hollow tube 1 is rotationally press-fitted in a state where the attachment of the bottom cover 3 is completed. Construction is also possible. In this case, as shown in FIG. 5, the soil 11 appropriately enters the lower portion of the hollow tube 1 below the bottom cover 3, and an air spring effect is exerted by compressing the air remaining in the lower portion of the hollow tube 1. As a result, when the soil reaches the hard stratum, the soil 11 may further enter the inside of the pipe, and the penetration into the hard soil may be improved.
[0022]
On the other hand, when the penetration resistance of the ground is large and it is difficult to attach the bottom cover 3 and seal the lower portion of the hollow tube 1 in advance, the hollow tube 1 is rotated with only the annular angle 12 attached. After press-fitting, the bottom cover 3 may be welded to the ring-shaped angle 12.
[0023]
In the example of FIG. 6, the bottom cover 3 is attached to the inner periphery of the hollow tube 1 in advance, while the pressure release hole 14 is provided at the lower portion of the hollow tube 1 so that the soil 11 can easily enter the lower portion of the hollow tube 1. In this embodiment, the rotational resistance is reduced by reducing the penetration resistance. 6 (a) and 6 (b) show a case where a pressure relief hole 14 is provided in the bottom cover 3 and the pressure relief hole 14 is closed with a plate 15 after the hollow tube 1 is rotationally press-fitted, thereby completing the formation of the bottom cover 3. It is an example. FIG. 6C shows an example in which the pressure relief hole 14 is opened in the side wall of the hollow tube 1 immediately below the bottom cover 3. In this case, it is not necessary to close the pressure relief hole 14 after the rotary press fitting.
[0024]
Further, when it is desired to avoid using fire in the hollow tubular body 1 after the rotary press-fitting, it is possible to form the bottom cover 3 ex post by various methods described below.
[0025]
FIG. 7 shows an example of a mode in which the bottom cover 3 is formed after the press-fitting by rotation when the soil 11 enters the hollow tube 1 to some extent. In the example of FIG. 7, the annular reinforcing steel 16 for fixing concrete is welded in advance to the upper part of the soil penetration position (the bottom lid formation position) on the inner periphery of the hollow tubular body 1. Next, concrete 17 is poured after the hollow tube is rotationally press-fitted, and further, a cinder concrete 18 having a waterproof joint at a joint portion with the hollow tube is cast. After the joint 19 is sealed 19, the waterproof coating 20 is applied to form the bottom cover 3. In addition, even when the groundwater level is shallower than the bottom lid formation position, the bottom lid 3 can be formed by casting underwater concrete.
[0026]
FIG. 8 shows an example of a mode in which the bottom lid 3 is formed after the rotary press-fitting when the soil 11 does not enter the hollow tube body much. In the example of FIG. 8, the ring-shaped angle 12 is welded in advance to the upper part of the soil penetration position (the bottom lid formation position) on the inner periphery of the hollow tubular body 1. Next, after the hollow tubular body 1 is rotationally press-fitted, a drop lid 21 inscribed in the hollow tubular body 1 is dropped and a cinder concrete 18 is poured. Hereinafter, the bottom cover 3 is formed in the same process as in the above example of FIG.
[0027]
After the hollow pipe 1 is rotationally press-fitted, the water pipe 4 and the return pipe 5 are installed inside the hollow pipe 1 to complete the underground heat exchanger of the first embodiment. The underground heat exchanger according to the first embodiment has a configuration in which the internal space of the hollow tubular body 1 is directly used as a circulation path of a heat medium, so that heat can be collected or radiated from surrounding soil. I have.
[0028]
FIG. 9 shows an example of the arrangement of the water supply pipe 4 and the return water pipe 5 in the underground heat exchanger of the first embodiment. When the hollow pipe 1 has a small diameter, a double pipe system in which one of the water pipe 4 and the return pipe 5 is inserted as shown in FIG. 9A (the water pipe 4 in the illustrated example). Is interpolated). When the diameter of the hollow pipe 1 is large, a steel pipe well system is used in which both the water supply pipe 4 and the return water pipe 5 are inserted as shown in FIG. 9B.
[0029]
In the underground heat exchanger of the first embodiment, the construction is completed only by installing at least one of the water supply pipe 4 and the return water pipe 5 inside the hollow pipe 1 after the rotary pipe 1 is rotationally press-fitted. The process can be significantly shortened as compared with the conventional underground heat exchanger, and the cost can be drastically reduced.
[0030]
<Second embodiment>
FIG. 10 is a diagram showing an underground heat exchanger according to the second embodiment. In the following embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0031]
In the second embodiment, a rotary press-fit steel pipe pile 22 as a foundation pile for supporting a building is rotationally press-fitted into the ground and buried, and a bottom lid 3 is formed near the tip of the rotary press-fit steel pipe pile 22 or at an intermediate portion thereof and hermetically sealed. And it is an underground heat exchanger constructed using the internal space of the rotary press-fit steel pipe pile 22. In the underground heat exchanger of the second embodiment, since the foundation pile originally required for supporting the building is also used as the heat exchanger, the cost of burying the heat exchanger alone is unnecessary, and further cost reduction can be achieved. Will be possible. As shown in FIG. 10 (a), as a method of taking out the water pipe 4 and the return pipe 5, the footing 22a is put on the top of the rotary press-fit steel pipe pile 22 as usual. To take out the water supply pipe 4 and the return water pipe 5 vertically by attaching a protrusion to the outer periphery of the footing joint at the top of the rotary press-fitting steel pipe pile 22 to transmit the supporting force from the pile to the footing. And a method using them in combination.
[0032]
<Third embodiment>
FIG. 11 is a diagram showing an underground heat exchanger according to the third embodiment. In the third embodiment, fins 1a for promoting heat exchange are attached to the outer periphery of the hollow tubular body 1. The shape of the fin 1a may be any shape that does not hinder the rotary press-fitting of the hollow tube 1, and for example, a small-diameter spiral fin formed by extending a drilling rotary blade upward may be considered. In FIG. 11, the fins 1a are provided over the entire length of the hollow tubular body 1. However, the fins 1a are effective in promoting heat exchange when groundwater is present. Fins 1a may be provided so as to cover the stratum where groundwater exists.
[0033]
<Fourth embodiment>
FIG. 12 is a diagram illustrating an underground heat exchanger according to a fourth embodiment. In the fourth embodiment, the insertion double tube 23a is inserted inside the hollow tube 1 and the heat medium is circulated inside the inside tube 23c and outside the outside tube 23b, so that heat is collected or radiated from the surrounding soil. It is configured to be able to. The fourth embodiment is advantageous in that the amount of the heat medium held in the underground heat exchanger can be reduced. For example, if a large-diameter hollow tube such as a foundation pile is used as an underground heat exchanger and an expensive antifreeze must be used as a heat medium in cold regions, the amount of antifreeze used can be reduced. This is advantageous in cost.
[0034]
The insertion double tube 23a used in the fourth embodiment is composed of an outer tube 23b having a smaller diameter than the inner diameter of the hollow tube 1, and an inner tube 23c arranged inside the outer tube 23b. The tip of the outer tube 23b is closed by a cap 24, and the top of the outer tube 23b is closed by a perforated cap 24a through which the inner tube 23c passes. An opening communicating with the inner tube 23c is provided near the distal end of the outer tube 23b. Then, between the outer tube 23b and the inner tube 23c in the insertion double tube 23a, air or a heat insulating material is sealed to form a heat insulating layer 25a.
[0035]
In the underground heat exchanger of the fourth embodiment, an insertion double pipe 23a is arranged inside the hollow pipe 1 and a return water pipe 5 is provided between the hollow pipe 1 and the insertion double pipe 23a. Is arranged. The heat medium sent from the inner tube 23c of the inner double tube 23a is circulated from the space between the hollow tube 1 and the inner double tube 23a to the return pipe 5 through the opening of the outer tube 23b. It is configured to Note that, in the fourth embodiment, an example in which the inner pipe 23c of the insertion double pipe 23a serves as a water supply pipe has been described. On the contrary, the hollow pipe 1 and the insertion double pipe 23 are used as the return pipe. The water supply pipe 4 may be disposed between the water supply pipe 23 and the nozzle 23a [not shown. ]
[0036]
<Fifth embodiment>
FIG. 13 is a diagram showing an underground heat exchanger according to the fifth embodiment. In the fifth embodiment, the inner tube 23 is arranged inside the hollow tube 1 and heat is radiated or radiated from the surrounding soil by circulating a heat medium inside the inner tube 23.
[0037]
The outer diameter of the inner tube 23 of the fifth embodiment is set smaller than the inner diameter of the hollow tube 1, and the inner tube 23 is inserted and arranged inside the hollow tube 1. The distal end of the inner cannula 23 is closed by a cap 24 or the like. The gap between the hollow tube 1 and the inner tube 23 is filled with a filler 25 such as water or mortar or grout. The water pipe 4 is arranged inside the inner pipe 23, and the upper end of the inner pipe 23 which protrudes from the hollow pipe 1 is connected to the return pipe 5, so that water or other heat medium is inserted into the inner pipe 23. 23 is circulated.
[0038]
<Sixth embodiment>
FIG. 14 is a diagram showing an underground heat exchanger according to the sixth embodiment. In the sixth embodiment, one set (one reciprocation) of the U-shaped pipe 26 configured by connecting the lower end portions of the water supply straight pipe and the return water straight pipe is inserted inside the hollow tubular body 1. The gap between the hollow tube body 1 and the U-shaped tube 26 is filled with a filler 25 such as water or mortar, grout, and the like. It is configured so that heat can be collected or radiated from the soil. In the example of FIG. 14, the number of U-shaped tubes 26 inserted into the hollow tube body 1 is one set (for one reciprocation). However, a configuration in which two sets (two reciprocations) of U-shaped tubes are arranged is also possible. Good [not shown].
[0039]
<Seventh embodiment>
FIG. 15 is a diagram illustrating an underground heat exchanger according to a seventh embodiment. The seventh embodiment is a modification of the fourth embodiment, and is an example in which the underground heat exchanger is extended by adding the hollow pipe 1 and the insertion double pipe 23a to secure a necessary heat exchange length. is there.
[0040]
In the installation operation of the underground heat exchanger according to the seventh embodiment, first, the distal end of the insertion double pipe 23a is inserted inside the hollow tubular body 27 with the blade at the distal end. The fixing of the inner double tube 23a to the hollow tubular body 27 with blades is performed by fitting the inner double tube 23a into a cap 24 attached to the bottom cover 3 of the hollow tubular body 27 with blades.
[0041]
Next, the hollow tube 27 with the blades is rotationally press-fitted to a predetermined position, the outer tube 23b and the inner tube 23c for extension are suspended, and the inner double tube 23a is extended. The outer tube 23b and the inner tube 23c are joined by a joint 29 having excellent watertightness, flexibility and elasticity.
[0042]
Further, the hollow tubular body 27 with the blades and the hollow tubular body 28 for extension are joined by in-situ circumferential welding or the like, and after the joining is completed, the integrated hollow tubular body 1 is rotationally press-fitted. The underground heat exchanger can be extended to a desired length by repeating the above-mentioned replenishment work as needed. After the completion of the rotation press-fitting of the hollow tube 1, the top of the outer tube 23b is closed with a perforated cap 24a, and a heat insulating layer 25a is formed between the outer tube 23b and the inner tube 23c. And the return water pipe 5 is arrange | positioned in the clearance gap between the hollow pipe body 1 and the insertion double pipe 23a, and an underground heat exchanger is completed.
[0043]
The installation work in the seventh embodiment is merely an example, and is not limited to the illustrated example. For example, after the hollow tube 27 with blades is added and extended by the hollow tube 28 to bury the required length, the insertion double tube 23a is extended by the joint 29 using a hanging fixture, and It may be dropped into the hollow tube 1 [not shown].
[0044]
<Eighth embodiment>
FIG. 16 is a diagram illustrating an underground heat exchanger according to an eighth embodiment. The eighth embodiment is a modification of the fifth embodiment, and is an example in which the underground heat exchanger is extended by adding the hollow tube 1 and the inner tube 23 to secure a necessary heat exchange length.
[0045]
In the installation operation of the underground heat exchanger according to the eighth embodiment, first, the small-diameter insertion tube 23 whose tip is closed is inserted into the inside of the hollow tubular body 27 with the blade at the tip. The space between the bladed hollow tube body 27 and the inner tube 23 is filled with a filler 25 such as mortar or grout, and the inner tube 23 is fixed.
[0046]
Next, the hollow tubular body 27 with blades is rotationally press-fitted to a predetermined position, the hollow tubular body 28 for extension is hung, and the hollow tubular body 27 with blades and the hollow tubular body 28 for extension are joined. The inner tube 23 is inserted into the refilling hollow tube 28, and the gap between the hollow tube 28 and the inner tube 23 is filled with a filler 25 such as mortar or grout. The joining between the intubation tubes 23 is performed by a joint 29 having excellent watertightness, flexibility, and elasticity, and the joining between the hollow tube body with blades 27 and the hollow tube for replenishment 28 is performed at the site circumference. This is performed by welding or the like. In addition, an injection hole for the filler 25 is provided in advance at the joint, and the filler 25 is injected into the gap of the joint 29 after the joining of the bladed hollow tube 27 and the refilling hollow tube 28, More preferably, the injection hole is closed.
[0047]
After the joining of the 27 winged hollow tubes and the refilling hollow tube 28 is completed, the integrated hollow tube 1 is rotationally press-fitted. The underground heat exchanger can be extended to a desired length by repeating the above-mentioned replenishment work as needed. After completion of the rotary press-fitting of the hollow tube 1, the water pipe 4 is arranged inside the inner tube 23 to complete the underground heat exchanger.
[0048]
The installation work in the eighth embodiment is merely an example, and is not limited to the illustrated example. For example, without additionally fixing the inner tube 23 to the hollow tube 28 in advance, the hollow tube 28 and the inner tube 23 are simultaneously suspended and joined together, and after the necessary length is buried, the filling material 25 is buried. May be filled. Alternatively, the insertion tube 23 may be fixed by a jig, and the filling material 25 may be filled after the embedding of the hollow tube 1 is completed (both are not shown).
[0049]
<Ninth embodiment>
FIG. 17 is a diagram illustrating an underground heat exchanger according to a ninth embodiment. The ninth embodiment is a modification of the sixth embodiment, and is an example in which the underground heat exchanger is extended by adding the hollow pipe 1 and the intubation 23 inside the U-shaped pipe 26. The ninth embodiment is different from the ninth embodiment in that a water supply straight pipe and a return water straight pipe arranged in a hollow pipe 28 are added to a U-shaped pipe 26 arranged in a hollow pipe 27 with blades. Different from the embodiment. In the example of FIG. 17, the number of U-shaped tubes 26 inserted into the hollow tube 1 is one set (for one reciprocation). However, a configuration in which two sets (for two reciprocations) of U-shaped tubes are arranged is also possible. Good.
[0050]
<Tenth embodiment>
FIG. 18 is a diagram illustrating the underground heat exchanger according to the tenth embodiment. In the tenth embodiment, underground heat exchange in which a hollow pipe 1 having no bottom lid is buried by rotary press-fitting, and then a U-shaped pipe 26 is pressed into the soil 11 filled in the hollow pipe 1. It is an example of installation of a vessel. In the tenth embodiment, it is determined that the U-shaped pipe 26 can be pressed into the soil 11 without removing the soil 11 without providing the bottom lid and securing the internal space of the hollow pipe 1 in advance ( For example, in the case of soft ground). After the U-shaped pipe 26 is pressed into the soil 11, the gap inside the hollow pipe 1 where the soil 11 has not entered is filled with a filler 25 such as mortar, grout, etc., and collected from the surrounding soil. It is configured to allow heat or heat radiation.
[0051]
<Eleventh embodiment>
FIG. 19 is a diagram showing an underground heat exchanger according to the seventh embodiment. In the eleventh embodiment, after the hollow tubular body 1 in which the U-shaped pipe 26 is inserted is rotationally press-fitted, only the tubular body 30 is pulled out and the U-shaped pipe 26 is arranged in the ground to form an underground heat exchanger. I do.
[0052]
The hollow pipe 1 used for the construction of the eleventh embodiment is configured by mechanically connecting a plurality of pipes 30 with a drilling lid 31 attached to the tip of the pipe 30. The joint between the pipe 30 and the excavation lid 31 is provided with, for example, a hook-shaped notch at an engagement portion of the pipe 30 inserted inside the excavation lid 31 and a projection provided on the inner periphery of the excavation lid 31. In addition, various joints such as those for engaging and disengaging the hook-shaped notch and the projection can be applied [not shown].
[0053]
The rotary blade 2 is provided at the lower end of the excavation lid 31. Furthermore, a swivel joint 32 is provided on the inner upper surface of the excavation lid 31, and the swivel joint 32 connects the folded portion at the lower end of the U-shaped tube 26 to the excavation lid 31.
[0054]
The construction of the underground heat exchanger of the eleventh embodiment is performed in the following steps.
{Circle around (1)} First, the excavation lid 31 is connected to the tip of the tube 30 by a joint to form the hollow tube 1, and the U-shaped tube 26 is arranged inside the hollow tube 1. The folded portion of the U-shaped tube 26 is connected to the excavation lid 31.
{Circle around (2)} Next, the hollow tubular body 1 is rotationally pressed into the ground. If the length of the hollow tube 1 is insufficient, the tube 30 is connected by a joint and rotary press-fitting is performed (see FIG. 19A).
{Circle around (3)} After the hollow tube 1 is rotationally press-fitted to a desired length, the joint between the tube 30 and the excavation lid 31 is released, and only the tube 30 is pulled out from the excavation hole (see FIG. 19B). . As a result, the excavation lid 31 and the U-shaped tube 26 are left inside the excavation hole (see FIG. 19C).
{Circle around (4)} Then, the underground heat exchanger is completed by filling the gap between the excavation hole and the U-shaped pipe 26 with the filler 25 such as water or mortar or grout (see FIG. 19D).
[0055]
FIG. 21 shows an embodiment of a high efficiency energy system using the underground heat exchanger of the present invention. In this high-efficiency energy system, a foundation pile / ground heat exchanger 41 and a dedicated pile ground heat exchanger 42 installed underground are connected to a heat pump 44 installed in a building 43 on the ground surface. In the air conditioning system, the heat pump 44 is connected to the air conditioner 45, and the cooling / heating air from the air conditioner 45 blows out to the space in the building 43 through the air conditioning duct 46. The heat pump 44 is connected to an indoor air conditioner 47 to cool and heat the room. Although the illustration shows an example of a fan coil unit which is an indoor air conditioner, a radiator or a floor heating pipe may be used in some cases. A heat storage tank 48 is installed between the heat pump 44, the air conditioner 45, and the indoor air conditioner 47 as needed. The heat storage tank 48 is installed when the capacity of the heat pump 44 is less than the peak load or when nighttime electric power is used. In the hot water supply system, the heat pump 44 and the hot water storage tank 50 are connected, the temperature of the water in the hot water storage tank is raised and the temperature is maintained, and the hot water is supplied to the hot water tap 49 at a stable hot water supply temperature.
[0056]
FIG. 22 shows another embodiment of the high-efficiency energy system using the underground heat exchanger of the present invention. In this high-efficiency energy system, a dedicated pile ground heat exchanger 42 installed underground, a snowmelt pipe 51 buried under the road surface, and a heat medium circulation pump 52 are connected.
[0057]
【The invention's effect】
The underground heat exchanger of the present invention can significantly reduce the number of steps as compared with the conventional underground heat exchanger that requires multiple steps. In addition, since there is no need to treat muddy water or waste soil and the unique rotary blade shape allows the hollow pipe to have excellent penetration, the construction cost for installing the underground heat exchanger can be greatly reduced.
[0058]
Further, in the present invention, the inner space of the highly watertight steel pipe pile can be used also as a heat exchanger by the shape of the rotating blades and the method of forming the bottom lid. Therefore, by using the foundation pile originally required for supporting the building as a heat exchanger, the cost of burying and installing the heat exchanger alone becomes unnecessary, and the cost can be further reduced.
[0059]
The geothermal heat utilization system is an excellent system that consumes very little energy. However, at present, its widespread use is hindered by extremely high construction costs. Therefore, it can be expected that the above effects of the present invention will promote its spread.
[Brief description of the drawings]
FIG. 1 is a diagram showing an underground heat exchanger according to a first embodiment.
FIG. 2 is a diagram showing a hollow tube used in the first embodiment.
FIG. 3 is a view showing a rotary blade used in the first embodiment.
FIG. 4 is a diagram showing an example of a mounting mode of a bottom cover.
FIG. 5 is a diagram illustrating an air spring effect when a bottom lid is previously formed in a hollow tubular body.
FIG. 6 is a diagram showing an example of installation of pressure relief holes in a hollow tubular body.
FIG. 7 is a diagram showing an example of an embodiment in which a bottom lid is formed after rotary press fitting.
FIG. 8 is a diagram showing an example of an embodiment in which a bottom lid is formed after rotational press fitting.
FIG. 9 is a diagram showing an example of arrangement of a water supply pipe and a return water pipe in the underground heat exchanger of the first embodiment.
FIG. 10 is a diagram showing an underground heat exchanger according to a second embodiment.
FIG. 11 is a diagram showing an underground heat exchanger according to a third embodiment.
FIG. 12 is a diagram showing an underground heat exchanger according to a fourth embodiment.
FIG. 13 is a diagram showing an underground heat exchanger according to a fifth embodiment.
FIG. 14 is a diagram illustrating an underground heat exchanger according to a sixth embodiment.
FIG. 15 is a diagram showing an underground heat exchanger according to a seventh embodiment.
FIG. 16 is a diagram showing an underground heat exchanger according to an eighth embodiment.
FIG. 17 is a diagram showing an underground heat exchanger according to a ninth embodiment.
FIG. 18 is a diagram showing an underground heat exchanger according to a tenth embodiment.
FIG. 19 is a diagram showing an underground heat exchanger according to an eleventh embodiment.
FIG. 20 is a view showing a construction process of a conventional U-tube type underground heat exchanger.
FIG. 21 is a diagram showing one embodiment of a high-efficiency energy system using the underground heat exchanger of the present invention.
FIG. 22 is a diagram showing another embodiment of the high efficiency energy system using the underground heat exchanger of the present invention.
[Explanation of symbols]
1 hollow tube
1a Fin
2 rotating blades
3 bottom lid
4 water pipe
5 Return water pipe
6 Start cutting surface
7 Drilling blade
8 End cut surface
8a Virtual termination section
9 Opening angle
10 Open end hole
11 soil
12 annular angles
13 Welds
14 Pressure relief hole
15 plates
16 Circular rebar
17 Concrete
18 Cinder concrete
19 Seal
20 Waterproof coating
21 Drop lid
22 Rotary press-fit steel pipe pile
22a Footing
23 Intubation
23a Interpolated double tube
23b outer tube
23c inner tube
24 caps
24a perforated cap
25 filler
25a insulation layer
26 U-shaped tube (U-shaped intubation)
27 Hollow tube with blade
28 Hollow tube for refilling
29 Fitting
30 tubes
31 Drilling lid
32 swivel joint
33 ground surface
37 Hollow Screw Auger
38 Temporary casing
40 mortar
41 Ground pile and ground heat exchanger
42 Dedicated pile underground heat exchanger
43 Building
44 heat pump
45 air conditioner
46 Air conditioning duct
47 Indoor air conditioner
48 thermal storage tank
49 hydrant
50 hot water storage tank
51 Snow melting pipe
52 Heat medium circulation pump

Claims

It is constructed by applying rotational force and downward force to a hollow tubular body having a rotating blade attached to a lower end portion and rotationally press-fitting the hollow tubular body, and using the internal space of the buried hollow tubular body. Underground heat exchanger.

The underground heat exchanger according to claim 1, wherein the hollow pipe is formed of a steel pipe, and the hollow pipe also serves as a rotary press-fit steel pipe pile as a foundation pile for supporting a building.

The rotating blade is a spiral blade, and an opening angle between a start end cut surface and an end cut surface of the rotary blade is set to 10 degrees to 90 degrees. Underground heat exchanger.

The geothermal heat according to any one of claims 1 to 3, wherein an open end hole having a diameter equal to or less than the inner diameter of the hollow tubular body is provided in a center portion of the rotating blade. Exchanger.

The ground according to any one of claims 1 to 4, wherein a bottom lid is provided at a lower end portion or an intermediate portion in the hollow tubular body, and the inside of the hollow tubular body is sealed. Medium heat exchanger.

The underground heat exchanger according to any one of claims 1 to 5, wherein a hollow tubular body having a bottom cover fixed in advance therein is buried by rotary press-fitting.

7. The underground heat exchanger according to claim 6, wherein a pressure relief hole is opened in a bottom cover or a hollow tube side wall lower than the bottom cover previously mounted inside.

A hollow tube body, to which a projection is previously attached, is buried by rotary press-fitting at a bottom lid forming position on the inner periphery, and a drop lid inscribed in the hollow tube body is buried and installed after the hollow tube body is buried and installed. The ground according to any one of claims 1 to 5, wherein the bottom is dropped inside the body, and the inner periphery of the hollow tube body and the dropping lid are fixed to each other to form a bottom lid. Medium heat exchanger.

A hollow tube having a projection previously attached to a bottom lid forming position on the inner periphery is buried by rotary press-fitting, and after embedding and installing the hollow tube, a temporal hardening material is placed at the bottom lid forming position in the hollow tube. The underground heat exchanger according to any one of claims 1 to 5, wherein a bottom lid is formed by filling the bottom cover.

A hollow tube body, to which a projection is previously attached, is buried by rotary press-fitting at a bottom lid forming position on the inner periphery, and a drop lid inscribed in the hollow tube body is buried and installed after the hollow tube body is buried and installed. The underground heat exchange according to any one of claims 1 to 5, wherein the bottom cover is formed by dropping into the inside of the body and filling a temporal hardening material above the drop cover to form a bottom cover. vessel.

The underground heat exchanger according to any one of claims 1 to 10, wherein at least one of an inner surface and an outer surface of the hollow tubular body is coated with anticorrosion.

The underground heat exchanger according to any one of claims 1 to 11, wherein a fin for promoting heat exchange is attached to an outer surface of the hollow tubular body.

At least one of the water pipe and the return pipe is installed inside the hollow pipe, and the heat medium can be circulated inside the hollow pipe, so that heat can be collected or radiated from the surrounding soil. The underground heat exchanger according to any one of claims 1 to 12, wherein:

An outer tube having a diameter smaller than the inner diameter of the hollow tube body and having a tip and a top closed, and an inner tube disposed inside the outer tube and communicating with the outside of the outer tube near the tip And an insertion double tube in which a heat insulating layer is formed by sealing air or a heat insulating material between the outer tube and the inner tube, is installed inside the hollow tube body, By using the inner pipe of the double pipe as one of the water pipe and the return pipe, and installing the other of the water pipe and the return pipe between the hollow pipe and the inserted double pipe, the heat medium The underground heat exchanger according to any one of claims 1 to 12, wherein the underground heat exchanger is configured to be able to circulate and to collect or release heat from surrounding soil.

An inner tube having a diameter smaller than the inner diameter of the hollow tube and having a closed end is disposed inside the hollow tube, and a gap between the hollow tube and the inner tube is filled with water or mortar or grout. And at least one of a water supply pipe and a return water pipe is installed inside the intubation pipe, a heat medium can circulate inside the intubation pipe, and heat is taken or radiated from surrounding soil. The underground heat exchanger according to claim 1, wherein the underground heat exchanger is configured to perform the following.

One or more sets of U-shaped intubation capable of circulating a heat medium are inserted inside the hollow tube, and a gap between the hollow tube and the U-shaped intubation is filled with a filler such as water or mortar or grout. The underground heat exchanger according to any one of claims 1 to 12, wherein the underground heat exchanger is filled and configured to be capable of collecting or radiating heat from surrounding soil.

An underground heat exchanger configured by adding a plurality of hollow tubes, wherein the hollow tube with blades at the tip has a diameter smaller than the inner diameter of the hollow tube, and the tip is closed. And an inner tube disposed inside the outer tube and communicated with the outside of the outer tube in the vicinity of the distal end portion, and an inner double tube is disposed, and the bladed hollow is provided. After the tube is rotationally press-fitted to a predetermined position, the outer tube and the inner tube are connected and extended, respectively, by a joint, and the required number of hollow tubes are connected to the bladed hollow tube, and the required number of hollow tubes are sequentially connected. The underground heat exchanger according to claim 14, wherein a heat insulating layer is formed by sealing air or a heat insulating material between the outer pipe and the inner pipe after securing the length.

An underground heat exchanger configured by adding a plurality of hollow pipes, wherein the hollow pipe with a blade at the tip has a diameter smaller than the inner diameter of the hollow pipe with a blade and the tip is closed. The inserted intubation is disposed, and after the hollow tube with blades is rotationally press-fitted to a predetermined position, the intubation is extended by a joint, and then the hollow tube with blades is added to the hollow tube with blades. 16. The underground heat exchanger according to claim 15, wherein a required length is secured by sequentially connecting a required number of the underground heat exchangers.

An underground heat exchanger configured by adding a plurality of hollow tubes, wherein at least one set of U-shaped inner intubation is inserted into the blade-mounted hollow tube at the tip, and After the hollow tube is rotationally press-fitted to a predetermined position, each intubation is extended by a joint, and the necessary number of hollow tubes are added to the hollow tube with blades and the required number of tubes are sequentially connected to secure the required length. The underground heat exchanger according to claim 16, wherein:

A hollow tube having no bottom cover is buried by rotary press-fitting, and a U-shaped intubation capable of circulating a heat medium is pressed into the soil inside the hollow tube, and the soil inside the hollow tube enters. The gap between the unshaped U-shaped intubation tube and the hollow tube body is filled with a filler such as water or mortar or grout so that heat can be collected or radiated from the surrounding soil. The underground heat exchanger according to any one of claims 1 to 4, characterized in that:

A drilling lid having rotating blades at the lower end is engaged with the lower end of the hollow tube, and at least one set of U-shaped inner tubes is inserted inside the hollow tube. After the hollow pipe body connected to the drilling lid and the drilling lid is engaged is buried by rotary press-fitting, the engagement between the hollow pipe body and the drilling lid is released to release the hollow pipe body. Only the hollow pipe body is pulled out, the space between the formed drilling hole and the U-shaped intubation is filled with water or a filler such as mortar or grout, and a heat medium is circulated inside the U-shaped intubation to circulate the surrounding soil. An underground heat exchanger configured to be able to collect or release heat.

22. The underground heat exchanger according to claim 1, wherein the heat pump is connected to the heat pump, and the heat pump is connected to a load processing facility such as an air conditioner or a snow melting pipe. A high-efficiency energy system characterized in that a heat storage tank is installed and cold or warm heat produced by a heat pump is used as one or more of heat sources for cooling, heating, and snow melting.

The underground heat exchanger according to any one of claims 1 to 21, wherein the heat pump is connected, the heat pump is connected to the hot water storage tank, the temperature of the water in the hot water storage tank is raised, and the temperature is maintained. A high-efficiency energy system used as a heat source for applications.

An underground heat exchanger according to any one of claims 1 to 21 and a load processing facility such as an air conditioner or a snow melting pipe are connected, and a heat storage tank is provided between the underground heat exchanger and the load processing facility as necessary. High efficiency characterized in that it is installed and directly used for one or more applications of cooling, heating and snow melting by sending ground temperature water in the underground heat exchanger to a load treatment facility by a circulation pump Energy system.