JP3281637B2 - High concentration dredging method - Google Patents
High concentration dredging methodInfo
- Publication number
- JP3281637B2 JP3281637B2 JP09953092A JP9953092A JP3281637B2 JP 3281637 B2 JP3281637 B2 JP 3281637B2 JP 09953092 A JP09953092 A JP 09953092A JP 9953092 A JP9953092 A JP 9953092A JP 3281637 B2 JP3281637 B2 JP 3281637B2
- Authority
- JP
- Japan
- Prior art keywords
- sand
- earth
- water
- discharge pipe
- high concentration
- 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.)
- Expired - Fee Related
Links
Landscapes
- Treatment Of Sludge (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、水底に堆積している土
砂に、余分な水を加えることなく浚渫を行う高濃度浚渫
方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-concentration dredging for dredging sediment deposited on a water bottom without adding extra water.
One in which relates to a method.
【０００２】[0002]
【従来の技術】従来、水底に堆積している泥土や土砂を
浚渫するには、その土砂に圧縮空気を混入させて、土砂
をプラグ状態で圧送する混気圧送方式が用いられている
が、土砂の性状によっては、掘削した土砂を混練するこ
とでスラリー輸送が可能な場合もあるので、混気圧送と
スラリー輸送とを適宜選択して行うことが、作業能率向
上をはかる上で望ましい。2. Description of the Related Art Conventionally, in order to dredge mud and earth and sand deposited on the bottom of a water, a mixed-pressure feeding method has been used in which compressed air is mixed into the earth and the earth and sand is pumped in a plug state. Depending on the properties of the earth and sand, slurry transportation may be possible by kneading the excavated earth and sand. Therefore, it is desirable to appropriately select the mixed pressure transportation and slurry transportation in order to improve work efficiency.
【０００３】一方、従来のポンプ式浚渫船によって水底
に堆積している土砂を掘削してスラリー輸送する場合、
水底に堆積している土砂を掘削、吸引する際に、カッタ
ーヘッドの周囲の水も一緒に吸引している。さらに、浚
渫船のスパッドの打ち替え等で掘削作業を中断する時
に、排砂管内に残存している土砂によって排砂管が閉塞
するのを防ぐために、水を送って排砂管内に残存してい
る土砂を埋立地等へ送っている。On the other hand, when excavating earth and sand deposited on the water bottom by a conventional pump dredger and transporting the slurry,
When excavating and sucking sediment deposited on the bottom of the water, the water around the cutter head is also sucked. In addition, when excavation work is interrupted by replacing a spud of a dredger, etc., water is sent and remains in the sand discharge pipe in order to prevent the sand discharge pipe from being blocked by sediment remaining in the sand discharge pipe. Sediment is sent to landfills.
【０００４】したがって、埋立地に余分な水が土砂と一
緒に搬入され、埋立地の容量が不足するという問題があ
り、また、埋立地に余水処理施設が必要となり、不経済
であるという問題もあった。一方、本発明者等は、水底
に堆積した泥土を高濃度で連続浚渫して処理場に圧送す
る高濃度浚渫装置に関する特開平２−８５４２６の発明
を先に案出しており、この装置は、混気圧送により土砂
を埋立地などへ輸送する手段として実用化されている。
そこで、本発明者等は混気圧送による高濃度浚渫装置を
用いて、混気圧送と、圧縮空気は注入しないスラリー輸
送とをその土砂の性状に合せて適宜選択して浚渫を行な
うことに着目して、種々検討および実験を重ねた結果本
発明に到達した。[0004] Therefore, there is a problem that excess water is carried into the landfill together with earth and sand, and the capacity of the landfill is insufficient, and a problem that a wastewater treatment facility is required in the landfill is uneconomical. There was also. On the other hand, the present inventors have previously devised the invention of Japanese Unexamined Patent Publication No. 2-85426 relating to a high-concentration dredging device that continuously dredges mud accumulated on the water bottom at a high concentration and pumps it to a treatment plant. It has been put to practical use as a means of transporting earth and sand to landfills, etc., by mixed pressure transport.
Therefore, the present inventors pay attention to performing dredging by appropriately selecting mixed pressure feeding and slurry transporting without injection of compressed air according to the properties of the soil using a high concentration dredging device by mixed pressure feeding. As a result of various studies and experiments, the present invention has been achieved.
【０００５】[0005]
【発明の解決しようとする課題】本発明は、前記従来の
問題点を解決するためになされたものであり、混気圧送
とスラリー輸送とを適宜選択して、可能な限り余分な水
を加えることなく、水底に堆積している土砂を掘削し、
埋立地などへ輸送する高濃度浚渫方法を提供することを
目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional problems, and it is necessary to appropriately select a mixed pressure feed and a slurry transfer to add extra water as much as possible. Without excavating the sediment deposited on the bottom of the water,
It is intended to provide a high-concentration dredging method for transporting to a landfill.
【０００６】[0006]
【課題を解決するための手段】本発明は、高濃度浚渫装
置を用いて掘削した土砂に圧縮空気を混入させてプラグ
状態で圧送する混気圧送と、掘削した土砂を混練して送
るスラリー輸送とを適宜選択して行い、かつスパッド打
ち替え等で掘削作業が中断する時に圧縮空気を排砂管内
に注入して土砂を混気圧送させる高濃度浚渫方法からな
る。SUMMARY OF THE INVENTION The present invention provides a highly concentrated dredging device.
Mix compressed air into earth and sand excavated using
Mixed-pressure feeding in which the pressure is pumped in the state, and kneading and sending the excavated earth and sand
And the appropriate slurry transport
When excavation work is interrupted due to changeover, etc.
From the high concentration dredging method of
You .
【０００７】[0007]
【作用】上記の高濃度浚渫方法では、すでに実用化され
ている混気圧送による高濃度浚渫装置を用いて、混気圧
送とスラリー輸送とを適宜選択して行ない、さらに、ス
パッド打ち替え等で掘削作業が中断する時に、圧縮空気
を注入して排砂管内の土砂を混気圧送により埋立地等へ
輸送するものであり、さらに、土砂の長距離輸送の時に
は、中継装置を用いることで混気圧送およびスラリー輸
送の両方に対して効率的に対応できるものである。In the above-mentioned high-concentration dredging method, the high-concentration dredging device that has already been put into practical use by the mixed-pressure feeding is used, and the mixed-pressure feeding and the slurry transport are appropriately selected and further performed. When the excavation work is interrupted, the compressed air is injected to transport the sediment in the sand discharge pipe to a landfill, etc. by mixed pressure transport. It can efficiently cope with both the pneumatic transportation and the slurry transportation.
【０００８】[0008]
【実施例】以下図面を参照して本発明の実施例を説明す
るが、図１は本発明の高濃度浚渫方法を適用する装置の
土砂掘削部の一実施例の概略側断面図、図２は図１の気
密フードの下端部の伸縮機構のスライド式の例を示す概
略断面図、図３は図１の気密フードの下端部の伸縮機構
の蛇腹式の例を示す概略断面図、図４は図１の排砂管の
延長上に設けられる中継装置の概略側面図、図５は土砂
がスラリー輸送された場合の逆止弁を備えた安全弁の作
動を示す系統図、図６は土砂が混気圧送で送られた場合
の逆止弁を備えた安全弁の作動を示す系統図である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side sectional view of an embodiment of an earth and sand excavation part of an apparatus to which the high concentration dredging method of the present invention is applied. FIG. 3 is a schematic cross-sectional view showing an example of a sliding type expansion / contraction mechanism at the lower end of the airtight hood of FIG. 1, FIG. 3 is a schematic cross-sectional view showing an example of a bellows type expansion / contraction mechanism of the lower end of the airtight hood of FIG. FIG. 5 is a schematic side view of a relay device provided on an extension of the sand drainage pipe of FIG. 1, FIG. 5 is a system diagram showing operation of a safety valve provided with a check valve when slurry is conveyed, and FIG. It is a system diagram showing operation of a safety valve provided with a check valve at the time of sending by mixed pressure feed.
【０００９】まず、図１に示すこの高濃度浚渫装置の土
砂掘削部は、前記特開平２−８５４２６の発明と同様
に、図示されていない浚渫船の船体とラダーにより継が
れ、操作されるものであり、水底に堆積した泥土や土砂
を高濃度で連続浚渫して埋立地などの処理場に圧送する
ものであるが、まず、図１に示すこの高濃度浚渫装置の
土砂掘削部の構成について説明すると、図示されていな
い攪拌翼を有する貯泥タンク１の外周に、矢印Ｒ方向に
回転可能なバケットホイール２を配置するが、このバケ
ットホイール２の各バケットは、底部に穴が設けられて
おり、また、貯泥タンク１の上部には土砂を投入する開
口部が設けられている。First, the earth and sand excavation part of this high-concentration dredging apparatus shown in FIG. 1 is connected and operated by a hull of a dredger (not shown) and a ladder similarly to the invention of Japanese Patent Application Laid-Open No. 2-85426. There is a method to continuously dredge mud and soil deposited at the bottom of the water at a high concentration and to pump it to a treatment plant such as a landfill. First, the configuration of the earth and sand excavation part of this high concentration dredging device shown in FIG. 1 will be described. Then, a bucket wheel 2 rotatable in the direction of arrow R is disposed on the outer periphery of the mud storage tank 1 having stirring blades (not shown). Each bucket of the bucket wheel 2 has a hole at the bottom. In addition, an opening for charging earth and sand is provided in the upper part of the mud storage tank 1.
【００１０】次に、バケットホイール２を覆う気密フー
ド３を設けて空気室６としており、この気密フード３の
下端部３Ａは、伸縮自在になっており、水底に堆積して
いる堆積土砂４の位置にできるだけ近づくように、気密
フード３の下端部３Ａの位置を調節できるようにしてい
る。なお、下端部３Ａの伸縮機構２０としては、図２に
示すようなスライド式機構、または図３に示すような蛇
腹式等既存のものを使用することができる。Next, an airtight hood 3 that covers the bucket wheel 2 is provided as an air chamber 6, and a lower end 3A of the airtight hood 3 is stretchable so that the sediment 4 deposited on the bottom of the water is formed. The position of the lower end 3A of the airtight hood 3 can be adjusted so as to be as close as possible to the position. In addition, as the extension mechanism 20 of the lower end portion 3A, a slide mechanism as shown in FIG. 2 or an existing mechanism such as a bellows type as shown in FIG. 3 can be used.
【００１１】さらに、気密フード３内に圧縮空気を注入
する圧縮空気の注入管を設けるとともに、貯泥タンク１
に渦巻きポンプを接続して、この渦巻ポンプの排砂管に
逆止弁を介して圧縮空気注入管を配置する。以上の構成
からなる高濃度浚渫装置によれば、気密フード３内の水
面Ｗは、湖水面ＷＳより水深Ｈの水底に堆積している堆
積底泥４の位置近くまで下げることができるので、掘削
時に水が混入するのを極力防ぐことができる。Further, a compressed air injection pipe for injecting compressed air into the hermetic hood 3 is provided, and a mud storage tank 1 is provided.
Is connected to a spiral pump, and a compressed air injection pipe is arranged via a check valve in a sand discharge pipe of the spiral pump. According to the high-concentration dredging device having the above-described configuration, the water surface W in the airtight hood 3 can be lowered to a position close to the position of the sediment 4 deposited on the bottom of the water depth H from the lake surface WS. It is possible to prevent water from being mixed as much as possible.
【００１２】なお、渦巻ポンプに代えてピストンポンプ
を使用することも可能である。次に、上記図１の高濃度
浚渫装置の土砂掘削部の排砂管の延長上に設けられる中
継装置の構成について図４により説明する。まず、上記
排砂管９の延長上に、土砂を溜める貯泥タンク１１を接
続し、この貯泥タンク１１にパイロット制御付の逆止弁
２１を備えた安全弁１４を配置する。It is also possible to use a piston pump instead of the spiral pump. Next, the structure of the relay device provided on the extension of the sand discharge pipe of the earth and sand excavation part of the high concentration dredging device of FIG. 1 will be described with reference to FIG. First, a mud storage tank 11 for storing earth and sand is connected to an extension of the sand discharge pipe 9, and a safety valve 14 having a check valve 21 with pilot control is arranged in the mud storage tank 11.
【００１３】土砂がこの排砂管９をスラリーで送られて
くる場合は、図５に示すように貯泥タンク１１の内部壁
面に備えられたフロート式液面計１７が送られた土砂に
より持上げられて、スラリー輸送であることを検知し、
信号は送られずに逆止弁２１が働き、安全弁１４から土
砂が噴出するのを防ぐ。また、土砂が排砂管９を混気圧
送で送られてくる場合は、図６に示すようにフロート式
液面計１７は空気では持上げられることがないので、混
気圧送であることを検知して信号Ｂを逆止弁２１に送り
電磁操作により逆止弁２１は逆止弁としての働きを停止
して所定圧力以上の圧縮空気を大気へ矢印Ａのごとく開
放する安全弁として働き、この場合、貯泥タンク１１内
へ搬入する排砂管９の管路の圧力より低い所定の圧力で
安全弁１４が開放するように設定する。When the earth and sand is sent through the sand discharge pipe 9 as slurry, as shown in FIG. 5, a float type liquid level gauge 17 provided on the inner wall surface of the mud storage tank 11 is lifted by the sent earth and sand. And detects that it is slurry transport,
The check valve 21 operates without a signal being sent to prevent the earth and sand from spouting from the safety valve 14. When the earth and sand is sent through the sand discharge pipe 9 by the mixed pressure feed, the float type liquid level gauge 17 is not lifted by the air as shown in FIG. Then, the signal B is sent to the check valve 21 and the check valve 21 stops working as a check valve by electromagnetic operation and works as a safety valve that releases compressed air having a predetermined pressure or more to the atmosphere as shown by an arrow A. In this case, The safety valve 14 is set to open at a predetermined pressure lower than the pressure of the pipe of the sand discharge pipe 9 carried into the mud storage tank 11.
【００１４】なお、本実施例では逆止弁の制御をフロー
ト式液面計により行っているが、貯泥タンクの底面に圧
力計を設置する等、他の手段を用いることも可能であ
る。次に、この貯泥タンク１１の下部に貯泥タンク１１
内の土砂排出管８を設け、土砂排出管８に加圧助勢用の
渦巻きポンプ１２を接続し、逆止弁１３を介して圧縮空
気注入口１５を有する排砂管１６を接続すると共に、渦
巻きポンプ１２の清掃や修理のためのバイパス管１９を
配設している。In this embodiment, the check valve is controlled by the float type liquid level gauge, but other means such as installing a pressure gauge on the bottom of the mud storage tank can be used. Next, a mud storage tank 11
And a vortex pump 12 for assisting pressurization is connected to the landslide discharge pipe 8, and a sand discharge pipe 16 having a compressed air inlet 15 is connected via a check valve 13. A bypass pipe 19 for cleaning and repairing the pump 12 is provided.
【００１５】ここで、従来、土砂の長距離輸送用に用い
られた中継装置では、混気圧送により貯泥タンク内へ送
られた圧縮空気は、大気に開放されていたのに対し、図
４に示す本発明の中継装置によれば、圧縮空気は安全弁
１４により一定の圧力より高い場合のみ排出されるの
で、圧力の損失が少なく効率がよい。また、混気圧送を
行わずに、渦巻きポンプ１２によるスラリー輸送を行う
場合には、逆止弁が働くので、土砂が貯泥タンク１１か
ら噴出するのを防止でき、したがって、この中継装置に
よれば、土砂が混気圧送で送られてくる場合と、スラリ
ー輸送で送られてくる場合との両方に効率的な対応が可
能である。なお、本中継装置においても、渦巻きポンプ
に代えて、ピストンポンプを使用することも可能であ
る。Here, in a conventional relay device used for long-distance transport of earth and sand, compressed air sent into a mud storage tank by mixed-pressure feeding is open to the atmosphere, whereas FIG. According to the relay device of the present invention, the compressed air is discharged by the safety valve 14 only when the pressure is higher than a certain pressure, so that the pressure loss is small and the efficiency is high. In addition, when the slurry is transported by the vortex pump 12 without performing the mixed-pressure feeding, the check valve operates, so that it is possible to prevent the earth and sand from being ejected from the mud storage tank 11. For example, it is possible to efficiently cope with both the case where earth and sand are sent by mixed pressure and the case where earth and sand are sent by slurry transportation. In this relay device, a piston pump can be used instead of the spiral pump.
【００１６】[0016]
(1) 本発明は、水底に堆積している泥土や土砂を浚渫
するに際し、土砂の性状に合わせて、適宜その土砂に圧
縮空気を混入させて土砂をプラグ状態で圧送する混気圧
送方式を用いたり、又は掘削した土砂を混練してスラリ
ー輸送を行うことにより、可能な限り余分な水を加える
ことなく、水底に堆積している土砂を掘削し、埋立地な
どへ泥土や土砂を効率よく輸送することができる。 (2) 従来スパッド打ち替え時には掘削作業が中断する
ので排砂管内に残存している土砂によって排砂管が閉塞
するのを防ぐために、水を送って排砂管内に残存してい
る土砂を埋立地等へ送っていたため、埋立地に余分な水
が土砂と一緒に搬入され、埋立地の容量が不足するとい
う問題があったが、本発明はスパッド打ち替え時に圧縮
空気を排砂管内に注入するようにしたから余分な水を送
る必要がなく、埋立地の容量不足を防止することができ
る。(1) The present invention dredges mud and soil deposited on the water bottom
In doing so, depending on the properties of the soil,
A mixed pressure that mixes compressed air to pump earth and sand in a plug state
Using a feeding method or kneading excavated earth and sand
-Add as much extra water as possible by transport
Without excavating the sediment deposited on the bottom of the water
Mud and earth and sand can be transported efficiently . (2) Excavation work is interrupted when replacing conventional spuds
The sediment remaining in the sandpipe blocks the sandpipe
Water to prevent water from remaining in the sandpipe.
Wastewater sent to landfills, etc.
Is brought in with the earth and sand, and the capacity of the landfill is insufficient.
However, the present invention compresses when changing spuds.
Air is injected into the sandpipe, so extra water is sent.
The need for landfills, which can prevent landfill capacity shortages.
You .
【図１】本発明の高濃度浚渫方法を適用する装置の土砂
掘削部の一実施例の概略側断面図である。FIG. 1 is a schematic cross-sectional side view of an embodiment of an earth and sand excavation part of an apparatus to which a high concentration dredging method of the present invention is applied.
【図２】図１の気密フードの下端部の伸縮機構のスライ
ド式の例を示す概略断面図である。FIG. 2 is a schematic cross-sectional view showing an example of a sliding type expansion and contraction mechanism at a lower end portion of the airtight hood of FIG.
【図３】図１の気密フードの下端部の伸縮機構の蛇腹式
の例を示す概略断面図である。FIG. 3 is a schematic sectional view showing a bellows-type example of a telescopic mechanism of a lower end portion of the airtight hood of FIG. 1;
【図４】図１の排砂管の延長上に設けられる中継装置の
概略側面図である。FIG. 4 is a schematic side view of a relay device provided on an extension of the sand discharging pipe of FIG. 1;
【図５】土砂がスラリー輸送された場合の逆止弁を備え
た安全弁の作動を示す系統図である。FIG. 5 is a system diagram showing the operation of a safety valve provided with a check valve when earth and sand are transported in slurry.
【図６】土砂が混気圧送で送られた場合の逆止弁を備え
た安全弁の作動を示す系統図である。FIG. 6 is a system diagram showing an operation of a safety valve provided with a check valve when earth and sand are sent by a mixed pressure feed.
１ 貯泥タンク ２ バケット
ホイール ３Ａ 下端部 ３ 気密フー
ド ８ 土砂排出管 ９ 排砂管 １１ 貯泥タンク １２ 渦巻き
ポンプ １３ 逆止弁 １４ 安全弁 １５ 圧縮空気注入口 １６ 排砂管 １７ フロート式液面計 ２０ 伸縮機
構 ２１ 逆止弁DESCRIPTION OF SYMBOLS 1 Mud storage tank 2 Bucket wheel 3A Lower end 3 Airtight hood 8 Sediment discharge pipe 9 Sand discharge pipe 11 Mud storage tank 12 Swirl pump 13 Check valve 14 Safety valve 15 Compressed air inlet 16 Sand discharge pipe 17 Float type liquid level gauge 20 Telescopic mechanism 21 Check valve
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) E02F 3/88 E02F 7/10 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) E02F 3/88 E02F 7/10
Claims (1)
圧縮空気を混入させてプラグ状態で圧送する混気圧送
と、掘削した土砂を混練して送るスラリー輸送とを適宜
選択して行い、かつスパッド打ち替え等で掘削作業が中
断する時に圧縮空気を排砂管内に注入して土砂を混気圧
送させる高濃度浚渫方法。A mixed pressure feed for mixing compressed air into soil excavated using a high-concentration dredging apparatus and feeding it in a plug state, and a slurry transportation for kneading and feeding excavated soil are appropriately selected and performed . Excavation work is ongoing due to spud replacement etc.
When cutting, pressurized air is injected into the sand discharge pipe to mix the soil and sand.
High concentration dredging method to send .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09953092A JP3281637B2 (en) | 1992-04-20 | 1992-04-20 | High concentration dredging method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09953092A JP3281637B2 (en) | 1992-04-20 | 1992-04-20 | High concentration dredging method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05295755A JPH05295755A (en) | 1993-11-09 |
| JP3281637B2 true JP3281637B2 (en) | 2002-05-13 |
Family
ID=14249781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP09953092A Expired - Fee Related JP3281637B2 (en) | 1992-04-20 | 1992-04-20 | High concentration dredging method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3281637B2 (en) |
-
1992
- 1992-04-20 JP JP09953092A patent/JP3281637B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05295755A (en) | 1993-11-09 |
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