JP2004222544A

JP2004222544A - Fish farming system for fish and shellfish

Info

Publication number: JP2004222544A
Application number: JP2003011679A
Authority: JP
Inventors: Hitoshi Kitamura; 仁史北村; Hideo Koizumi; 秀雄小泉; Atsushi Tsuji; 敦志辻
Original assignee: RIKUJO YOSHOKU KOGAKU KENKYUSH; Rikujo Yoshoku Kogaku Kenkyusho KK
Current assignee: RIKUJO YOSHOKU KOGAKU KENKYUSH; Rikujo Yoshoku Kogaku Kenkyusho KK
Priority date: 2003-01-20
Filing date: 2003-01-20
Publication date: 2004-08-12
Anticipated expiration: 2023-01-20
Also published as: JP3887320B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fish farming system for fish and shellfish, which efficiently removes large foreign matters on a sand bed in a rearing tank and is cleaned. <P>SOLUTION: The fish farming system for fish and shellfish is equipped with the rearing tank 1 for rearing fish and shellfish having the sand bed 8 on the bottom, a rearing water cleaning means 3 for cleaning rearing water 2 in the rearing tank 1 and a circulation means 4 for circulating the rearing water 2 between the rearing tank 1 and the rearing water cleaning means 3. A foreign matter discharge port 30 is arranged at one end part of the rearing tank 1 and a water flow generation means 13 for generating a water flow to the foreign matter discharge port 30 is installed at the other end part opposed to the foreign matter discharge port 30. After a water level above the sand bed 8 is lowered, a water-flow is generated by the water flow generation means 13 and foreign matters on the sand bed 8 are discharged from the foreign matter discharge port 30 by the water flow. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、飼育水を循環させて再利用しながら、飼育槽でエビや魚など魚介類を養殖するようにした魚介類の養殖システムにおいて、飼育槽の砂床の異物を除去する技術に関するものである。
【０００２】
【従来の技術】
飼育槽の飼育水を浄化して循環させることによって、飼育槽内で魚介類を高密度に養殖するシステムが従来から種々提案されている。そしてエビなど砂に潜る習性を有する魚介類を養殖する場合には、飼育槽の底部に砂を敷いて砂床を形成することが行われている（例えば特許文献１参照）。
【０００３】
このような飼育槽の底部に砂床を形成した養殖システムあって、砂床の上にはエビの抜け殻や残餌など、固形の異物が残留し易い。そこで特許文献１では、砂床に下側から上方に向けて水流を通過させるようにすることによって、異物を浮遊させ、浮遊させた異物を飼育槽の外部に排除するようにしている。
【０００４】
【特許文献１】
特開２００２−１５９２４１号公報
【０００５】
【発明が解決しようとする課題】
しかし、砂床に下側から上方に向けて水流を通過させて異物を浮遊させる場合、砂床の砂が舞い上がらない程度の緩い水流を砂床に通過させるようにする必要があるが、このような緩い水流では、砂床の上に残留する抜け殻や残餌のような大きな固形の異物を浮遊させることは難しく、砂床の上の大きな異物の除去を十分に行なうことができないという問題を有するものであった。
【０００６】
本発明は上記の点に鑑みてなされたものであり、飼育槽の砂床の上の大きな異物を効率よく除去して清掃することができる魚介類の養殖システムを提供することを目的とするものである。
【０００７】
【課題を解決するための手段】
本発明の請求項１に係る魚介類の養殖システムは、底部に砂床８を設けた魚介類飼育用の飼育槽１と、飼育槽１の飼育水２を浄化する飼育水浄化手段３と、飼育水２を飼育槽１と飼育水浄化手段３の間で循環させる循環手段４とを備えた魚介類の養殖システムにおいて、飼育槽１の一端部に異物排出口３０を設けると共に、異物排出口３０と対向する他端部に異物排出口３０へ向けて水流を発生させる水流発生手段１３を設け、砂床８上の水位を下げた後に水流発生手段１３で水流を発生させて、砂床８上の異物を水流で異物排出口３０に排出するようにして成ることを特徴とするものである。
【０００８】
また請求項２の発明は、請求項１において、飼育槽１の側壁に砂床８の上面よりやや上方位置において異物排出口３０を設けると共に異物排出口３０より上側位置において飼育槽１内の飼育水２を流出させる排水口２９を設け、排水口２９を循環手段４に接続して成ることを特徴とするものである。
【０００９】
また請求項３の発明は、請求項１又は２において、水とともに異物排出口３０に排出される異物を貯溜する貯溜水槽３３を具備して成ることを特徴とするものである。
【００１０】
また請求項４の発明は、請求項１乃至３のいずれかにおいて、上端が砂床８の上面より上で且つ、飼育水２の水面より下に位置する仕切り壁９を飼育槽１内に複数設け、隣り合う各仕切り壁９間において異物排出口３０と水流発生手段１３とを対向させて設けて成ることを特徴とするものである。
【００１１】
また請求項５の発明は、請求項１乃至４のいずれかにおいて、飼育槽１を一対設けると共に各飼育槽１を循環手段４で接続し、一方の飼育槽１内の飼育水２を循環手段４を通じて他方の飼育槽１へ送ることによって、一方の飼育槽１の砂床８上の水位を下げるようにして成ることを特徴とするものである。
【００１２】
また請求項６の発明は、請求項５において、各飼育槽１に設けた水流発生手段１３をそれぞれ循環手段４に接続し、一方の飼育槽１内の飼育水２を循環手段４を通じて他方の飼育槽１へ送ることによって、一方の飼育槽１の砂床８上の水位を下げると共に他方の飼育槽１の水位を上昇させた後、この水位の差によって他方の飼育槽１内の飼育水２を循環手段４を通じて一方の飼育槽１に設けた水流発生手段１３に送ると共に水流発生手段１３から吐出させて水流を発生させるようにして成ることを特徴とするものである。
【００１３】
また請求項７の発明は、請求項１乃至６のいずれかにおいて、砂床８の下側に砂の粒径より大きい目を有する捕獲用ネット１１を張設し、捕獲用ネット１１を砂床８の上方へ引き上げることによって、捕獲用ネット１１の上に魚介類を捕獲するようにして成ることを特徴とするものである。
【００１４】
また請求項８の発明は、請求項７において、捕獲用ネット１１を複数枚重ねて砂床８の下側に張設し、上から１枚ずつ捕獲用ネット１１を引き上げるようにして成ることを特徴とするものである。
【００１５】
【発明の実施の形態】
以下、本発明の実施の形態を説明する。
【００１６】
図１３は養殖システムの概略構成を示すものであり、魚介類を飼育する飼育槽１と、飼育槽１の飼育水２を浄化する飼育水浄化手段３と、飼育水２を飼育槽１と飼育水浄化手段２の間で循環させる循環手段４とを備えて形成してある。図１３のシステムでは、沈殿槽１５、生物処理濾過槽１６、紫外線殺菌槽１７で飼育水浄化手段３を形成するようにしてあり、各槽を接続する配管及びポンプ１８によって循環手段４を形成するようにしてある。この養殖システムにあって、飼育槽１の水はポンプ１８によってクローズドサイクルで循環させるようにしてあり、飼育槽１の飼育水２はまず沈殿槽１５に流入し、飼育槽１内で発生したＳＳや排泄物、残餌などの固形分が、自然沈降とサイクロン水流によって飼育水２から分離されて除去される。生物処理濾過槽１６には微生物が付着した濾材が充填してあり、沈殿槽１５を通過した飼育水２が生物処理濾過槽１６に流入すると、魚介類の排泄物から発生するアンモニアが微生物の硝化反応により硝酸まで分解される。また沈殿槽１５で取り切れなかった細かなＳＳはこの生物処理濾過槽１６で濾過して除去される。生物処理濾過槽１６を通過した飼育水２には紫外線殺菌槽１７において紫外線が照射され、有害微生物細菌が殺菌される。このようにして沈殿槽１５、生物処理濾過槽１６、紫外線殺菌槽１７で浄化された飼育水２は、ポンプ１８によって飼育槽１に返送されるようになっている。
【００１７】
飼育槽１は図２及び図３に示すように平面形状を細長い矩形に形成してあり、飼育槽１を長手方向に等間隔に仕切るように仕切り壁９が一定間隔に底面から立ち上げて設けてある。この仕切り壁９は図４に示すように飼育槽１内の飼育水２の水面より上端が低くなる高さに形成してあり、図の実施の形態では仕切り壁９を４箇所に設けて、飼育槽１内を５つの室１４ａ〜１４ｅに仕切るようにしてある。この各室１４ａ〜１４ｅの底部には図１に示すように下面に脚２０を設けた架台２１が設置してある。架台２１はすのこや穴明きパレットなど、上下に水が自由に通過できる多数の通孔２２を全面に設けたもので形成してある。この架台２１の上には砂床８の砂の粒径より目開きが小さい下地ネット２３が敷いてあり、下地ネット２３の上にさらに捕獲用ネット１１が敷いてある。捕獲用ネット１１の目開きの大きさは、砂床８の砂の粒径より大きく、且つ飼育槽１で飼育する魚介類の出荷時の大きさよりも小さい寸法に設定してある。そしてこの捕獲用ネット１１の上に砂を撒いて砂床８が形成してある。砂床８は上面が仕切り壁９の上端よりやや下側になるように形成されるものである。
【００１８】
飼育槽１に設けた上記の仕切り壁９のうち、飼育槽１の長手方向の両端に位置する仕切り壁９の上側に仕切り板１０が設けてある。この仕切り板１０は、飼育槽１の長手側の側壁の各内面に設けた一対の平行なガイド板２４間に両側端を差し込むことによって、仕切り壁９の上に取り付けるようにしてあり、ガイド板２４間から上方に抜き出すことによって、仕切り板１０を取り外すことができるようにしてある。そして仕切り壁９の上に取り付けた仕切り板１０の上端は飼育槽１内の飼育水２の水面よりも上方に突出しているものであり、この仕切り板１０と仕切り壁９とによって仕切り部６が形成され、飼育槽１内を仕切り部６で３槽に分割し、両端部の室１４ａと室１４ｅでそれぞれ初期育成槽５を形成すると共に、中央部の室１４ｂ〜１４ｄで共通育成槽７を形成することができるようにしてある。このように形成される飼育槽１は一対用いられるものであり、一方の飼育槽１ａと他方の飼育槽１ｂを同じ高さレベルにおいて、飼育水浄化手段３の両側に配置するようにしてある。
【００１９】
飼育槽１の飼育水浄化手段３の側の側壁の外面にはその長手方向のほぼ全長に沿って排水樋２６が設けてあり、図１に示すように排水樋２６内は上部の排水室２７と下部の清掃用排水室２８とに上下２段の室に仕切ってある。そして飼育槽１の各室１４ａ〜１４ｅにおいてそれぞれ側壁の上部に形成した排水口２９を排水室２７に開口させてあり、各室１４ａ〜１４ｅにおいてそれぞれ側壁の下部に形成した異物排出口３０を清掃用排水室２８に開口させてある。排水口２９は飼育槽１内の飼育水２の水面付近の高さに配置してあり、異物排出口３０は砂床８の上面より若干高い位置に配置してある。排水樋２６の排水室２７は返送用配管３１によって沈殿槽１５に接続してあり、清掃用排水室２８は清掃用配管３２によって、飼育水浄化手段３と同じ並びに配置した貯溜水槽３３に接続してある。ここで図１に示すように、一対の飼育槽１のうち、一方の飼育槽１ａの排水室２７は返送用配管３１ａで、他方の飼育槽１ｂの排水室２７は返送用配管３１ｂでそれぞれ沈殿槽１５に接続するようにしてある。また一方の飼育槽１ａの清掃用排水室２８は清掃用配管３２ａで、他方の飼育槽１ｂの清掃用排水室２８は清掃用配管３２ｂでそれぞれ貯溜水槽３３に接続するようにしてある。
【００２０】
また、飼育槽１に上記のように形成した排水口２９と異物排出口３０を覆うように、各室１４ａ〜１４ｅの側壁の内面に網板３５が設けてある。網板３５は開口部にメッシュ３６を張って形成してあり、図５のようにメッシュ３６で排水口２９と異物排出口３０が覆われるようにしてある。このメッシュ３６の網の目の大きさは、養殖する魚介類の大きさより小さく、飼育槽１内に発生する残餌や脱皮殻などの固形異物より大きい寸法に設定してある。網板３５はその両端を飼育槽１の側壁内面に設けた一対のガイドレール３７に差し込むことによって上下方向にスライド自在にしてあり、網板３５の上端部に設けた上下に長い長孔３８に固定用ボルト３９を通して飼育槽１の側壁にねじ込むことによって、固定用ボルト３９で網板３５を固定するようにしてある。固定用ボルト３９を緩めることによって、長孔３８の上下長の範囲で網板３５の高さ調整をすることができるものであり、網板３５の下端が砂床８に埋まるように高さ調整をするようにしてある。
【００２１】
また、飼育槽１の各室１４ａ〜１４ｅにおいて、飼育槽１の底部に凹陥部４１が形成してあり、図１に示すように凹陥部４１の中央部に給水口４２が形成してある。この給水口４２にはポンプ１８に接続される給水用配管４３から分岐した分岐給水配管４４が接続してあり、給水口４２の上方位置には脚４５で飼育槽１の底部に固定した邪魔板４６が配置してある。さらに飼育槽１の排水樋２６を設けた側と反対側の側壁の内側には、各室１４ａ〜１４ｅにおいてそれぞれ吐出パイプ４７が配置してある。吐出パイプ４７は砂床８の上面の付近において飼育槽１の側壁と平行に水平に配置してあり、吐出パイプ４７には異物排出口３０の側に向けて開口する吐出口４８が長手方向の複数箇所に設けてある。この吐出口４８を設けた吐出パイプ４７によって水流発生手段１３が形成されるものである。吐出パイプ４７には給水用配管４３から分岐した吐出配管４９が接続してあり、吐出配管４９は逆Ｕ字形に屈曲して飼育槽１の側壁を乗り越えて吐出パイプ４７に接続されるようにしてある。ここで図２に示すように、一対の飼育槽１ａ，１ｂのうち、一方の飼育槽１ａには給水用配管４３ａを配管して分岐給水配管４４ａを給水口４２に接続するようにしてあり、他方の飼育槽１ｂには給水用配管４３ｂを配管して分岐給水配管４４ｂを給水口４２に接続するようにしてある。また一方の飼育槽１ａの吐出パイプ４７には吐出配管４９ａを、他方の飼育槽１ｂの吐出パイプ４７には吐出配管４９ｂを接続するようにしてある。
【００２２】
沈殿槽１５と生物処理濾過槽１６及び紫外線殺菌槽１７を接続する接続配管５１、紫外線殺菌槽１７とポンプ１８を接続する接続配管５２及び、上記の返送用配管３１ａ，３１ｂ、給水用配管４３ａ，４３ｂ、給水分岐配管４４ａ，４４ｂによって循環手段４の配管が形成されるものである。そして図２に示すように、給水用配管４３ａ，４３ｂ、給水分岐配管４４ａ，４４ｂ、返送用配管３１ａ，３１ｂ、清掃用配管３２ａ，３２ｂ、吐出配管４９ａ，４９ｂには、それぞれ電磁弁などで形成される開閉弁５３ａ〜５３ｊが設けてある。
【００２３】
上記のように形成される養殖システムにおいて、飼育槽１ａ，１ｂで魚介類を養殖する通常運転時には、給水用配管４３ａ，４３ｂの各開閉弁５３ａ，５３ｂ、給水分岐配管４４ａ，４４ｂの各開閉弁５３ｃ、５３ｄ、返送用配管３１ａ，３１ｂの各開閉弁５３ｅ，５３ｆを開くと共に、清掃用配管３２ａ，３２ｂの各開閉弁５３ｇ，５３ｈ、吐出配管４９ａ，４９ｂの各開閉弁５３ｉ，５３ｊを閉じた状態でポンプ１８を作動させるものであり、飼育水浄化手段３で浄化された飼育水２は給水用配管４３ａ，４３ｂから給水分岐配管４４ａ，４４ｂへ送られ、一対の各飼育槽１ａ，１ｂ内に給水口４２から給水される。このとき、図１にイ矢印で示すように、給水口４２から上方へ吹き出された飼育水２は邪魔板４６の下面に当たり、四方に分散された状態で均一に飼育槽１ａ，１ｂ内を流れるようになっている。飼育槽１ａ，１ｂ内の飼育水２は、その水面付近の水が排水口２９から排水樋２６の排水室２７に流れ込むことによって、一定の水位を保つようになっている。排水室２７に流れ込んだ飼育水２は返送用配管３１ａ，３１ｂから排出され、沈殿槽１５へ送られて飼育水浄化手段３で浄化処理される。
【００２４】
上記のように飼育槽１ａ，１ｂで魚介類の養殖を行なうと、砂床８の上に魚介類の脱皮殻や残餌などの固形異物が溜まってくるので、これらを除去する必要がある。以下、この固形異物を除去する掃除の操作について説明する。
【００２５】
まず、上記の通常の養殖運転の状態で、図７に示すように、飼育槽１ａに接続される給水用配管４３ａの開閉弁５３ａと、飼育槽１ｂに接続される返送用配管３１ｂの開閉弁５３ｆを閉じる（図７において開状態の開閉弁を白抜きで、閉状態の開閉弁を黒塗りで示す。図８、図９においても同じ）。従って飼育槽１ｂに接続される給水用配管４３ｂの開閉弁５３ｂ、給水分岐配管４４ａ，４４ｂの各開閉弁５３ｃ、５３ｄ、飼育槽１ａに接続される返送用配管３１ａの開閉弁５３ｅは開いており、清掃用配管３２ａ，３２ｂの各開閉弁５３ｇ，５３ｈ、吐出配管４９ａ，４９ｂの各開閉弁５３ｉ，５３ｊは閉じている。そしてこの状態でポンプ１８を作動させると、飼育槽１ｂには給水用配管４３ｂと給水分岐配管４４ｂを通して飼育水２が給水されるが、飼育槽１ｂの返送用配管３１ｂは閉じているので飼育槽１ｂからは飼育水２が排出されず、図６（ａ）のように飼育槽１ｂ内の飼育水２の水位は通常の養殖運転のときよりも上昇する。一方、給水用配管４３ａが閉じているので飼育槽１ａには飼育水２が給水されないが、飼育槽１ａの返送用配管３１ａは開いているので、飼育槽１ａ内の飼育水２が排水口２９から排水室２７に流入すると返送用配管３１ａから沈殿槽１５へと排水され、図６（ａ）のように飼育槽１ａ内の飼育水２の水位は下がる。
【００２６】
飼育槽１ａ内の飼育水２の水位が所定高さ（例えば砂床８の上面から５ｃｍ）まで下がると、フロートスイッチなどの制御でポンプ１８の作動を停止させ、図８に示すように、飼育槽１ｂに接続される給水用配管４３ｂの開閉弁５３ｂと飼育槽１ａの返送用配管３１ａの開閉弁５３ｅを閉じ、飼育槽１ａの清掃用配管３２ａの開閉弁５３ｇを開く。このように飼育槽１ａの清掃用配管３２ａを開くことによって、飼育槽１ａの清掃用排水室２８内の飼育水２は貯溜水槽３３に排出されるので、水位の下がった飼育槽１ａの砂床８上の飼育水２は異物排出口３０から清掃用排水室２８に流入し、この流れと共に砂床８の上の固形異物も異物排出口３０から清掃用排水室２８に流入する。清掃用排水室２８に流入した固形異物は飼育水２と共に清掃用配管３２ａを通して貯溜水槽３３に排出される。
【００２７】
このように貯溜水槽３３に排出されることによって飼育槽１ａの飼育水２の水位がさらに下がり、図１に二点鎖線で示すように異物排出口３０のやや上方位置にまでなると、図９に示すように、給水用配管４３ａ，４３ｂの開閉弁５３ａ，５３ｂを開き、飼育槽１ａの給水分岐配管４４ａの開閉弁５３ｃを閉じると共に飼育槽１ａの吐出配管４９ａの開閉弁５３ｉを開く。すると、飼育槽１ｂの給水分岐配管４４ｂと飼育槽１ａの吐出配管４９ａは給水用配管４３ａ，４３ｂを通して連通し、しかも既述の図６（ａ）のように飼育槽１ｂの飼育水２の水位が飼育槽１ａの飼育水２の水位よりも高くなっているので、この水位の差によって、飼育槽１ｂ内の飼育水２は給水口４２から給水分岐配管４４ｂに流れ出し、給水用配管４３ｂ及び給水用配管４３ａを通過して飼育槽１ａの吐出配管４９ａに送られ、飼育槽１ａ内に配置した吐出パイプ４７から飼育水２が吐出される。
【００２８】
このようにして、吐出パイプ４７の吐出口４８から飼育水２を異物排出口３０に向けて図１のロ矢印のように吐出させることによって、砂床８上の固形異物を水流で洗い流して、異物排出口３０から清掃用排水室２８に流入させることができ、固形異物を清掃用配管３２ａを通して貯溜水槽３３に排出することができるものである。このとき、飼育槽１ａ内において砂床８上の飼育水２の水位は低くなっているので、吐出パイプ４７から飼育水２を吐出させることによって強い水流を生じさせることができるものであり、砂床８上の固形異物を勢いの高い水流で効率よく洗い流すことができるものである。ここで、異物排出口３０はメッシュ３６で塞いであるので、飼育している魚介類は異物排出口３０に入ることができないが、抜け殻や残餌などの異物はメッシュ３６を通過して異物排出口３０から排出することができるものである。
【００２９】
上記のようにして一方の飼育槽１ａの砂床８上に残留する固形異物の清掃を行なうことができるが、他方の飼育槽１ｂの清掃についても、上記の操作に準じて行なうことができる。すなわち、まず飼育水槽１ｂに接続される給水用配管４３ｂの開閉弁５３ｂと、飼育槽１ａに接続される返送用配管３１ａの開閉弁５３ｅを閉じ、この状態でポンプ１８を作動させると、図６（ｂ）のように飼育槽１ａ内の飼育水２の水位は通常の養殖運転のときよりも上昇すると共に飼育槽１ｂ内の飼育水２の水位は下がる。次に、ポンプ１８の作動を停止させ、飼育槽１ａに接続される給水用配管４３ａの開閉弁５３ａと飼育槽１ｂの返送用配管３１ｂの開閉弁５３ｆを閉じ、飼育槽１ｂの清掃用配管３２ｂの開閉弁５３ｈを開く。このように清掃用配管３２ｂを開くことによって、水位の下がった飼育槽１ｂの飼育水２は異物排出口３０から清掃用排水室２８に流入し、この流れと共に砂床８の上の固形異物も清掃用排水室２８に流入して、清掃用配管３２ｂを通して貯溜水槽３３に排出される。このように飼育槽１ｂの飼育水２の水位がさらに下がって、図１に二点鎖線で示す位置にまでなると、給水用配管４３ａ，４３ｂの開閉弁５３ａ，５３ｂを開き、飼育槽１ｂの給水分岐配管４４ｂの開閉弁５３ｄを閉じると共に飼育槽１ｂの吐出配管４９ｂの開閉弁５３ｊを開く。すると、図６（ｂ）のように飼育槽１ａの飼育水２の水位が飼育槽１ｂの飼育水２の水位よりも高くなっているので、この水位の差によって、飼育槽１ａ内の飼育水２は給水口４２から給水分岐配管４４ａに流れ出し、給水用配管４３ａ及び給水用配管４３ｂを通過して飼育槽１ｂの吐出配管４９ｂに送られ、飼育槽１ｂ内に配置した吐出パイプ４７の吐出口４８から飼育水２が異物排出口３０に向けて図１のロ矢印のように吐出され、砂床８上の固形異物を水流で洗い流して、異物排出口３０から清掃用排水室２８に流入させることができ、固形異物を清掃用配管３２ｂを通して貯溜水槽３３に排出することができるものである。
【００３０】
ここで、図４に示すように、飼育槽１は砂床８の上面に突出する仕切り壁９によって仕切られており、水流発生手段１３を形成する吐出パイプ４７は隣り合う仕切り壁９間に配置してある。このため、吐出パイプ４７の吐出口４８から飼育水２を吐出して砂床８上の固形異物を水流で洗い流すにあたって、水流が両側の仕切り壁９でガイドされて横に広がるようなことがなくなり、砂床８上の固形異物を効率よく洗い流して異物排出口３０から清掃用排水室２８に排出することができるものである。
【００３１】
また、飼育槽１の各室１４ａ〜１４ｂに配置した吐出パイプ４７のうち、一室の吐出パイプ４７の開閉弁５３ｉ（５３ｊ）を開き、他の室の吐出パイプ４７の開閉弁５３ｉ（５３ｊ）を閉じるようにすれば、一つの吐出パイプ４７から集中して飼育水２を吐出させることができ、強い水流で砂床８上の固形異物を効率高く洗い流すことができる。そしてこのとき、各室１４ａ〜１４ｂは上記のように砂床８の上面に突出する仕切り壁９によって仕切られているので、他の吐出パイプ４７を閉じた状態で吐出パイプ４７から飼育水２を吐出させる場合、この吐出パイプ４７から吐出させた飼育水２が他の室に広がってしまうことを仕切り壁４９で防ぐことができるものであり、一つの室に集中させて強い水流を起こすことができ、この室の砂床８上の異物の除去を効率良く行なうことができるものである。
【００３２】
上記のように貯溜水槽３３に流入した固形異物を含む飼育水２は、固形異物を自然沈殿させた後、その上澄み部分を別途のポンプで飼育槽１あるいは飼育水浄化手段３へと返送して養殖に再使用される。従って養殖システムに補充する飼育水２の量を最低限にすることができるものである。また沈降した固形異物は、生ゴミ処理機などで分解処理される。尚、貯溜水槽３３は、このように固形異物を含む飼育水２を一時貯溜して固形異物の沈殿分離するために使用する他に、砂床８の砂を次亜塩素酸ナトリウムなどで洗浄するために利用したりすることもできるものである。
【００３３】
次に、上記のように飼育水２を飼育槽１ａ，１ｂと飼育水浄化手段３の間で循環させながら、飼育槽１ａ，１ｂで魚介類を養殖する方法について、魚介類として例えばクルマエビを養殖する場合を説明する。まず、各飼育槽１ａ，１ｂにおいて、室１４ａと室１４ｂの間の仕切り板１０を残すと共に、室１４ｄと室１４ｅの間の仕切り板１０を抜いて外すことによって、図１０（ａ）に示すように、仕切り壁９と仕切り板１０からなる仕切り部６で各飼育槽１ａ，１ｂ内を、室１４ａからなる第１の初期育成槽５ａと、室１４ｂ〜１４ｄからなる共通育成槽７及び室１４ｅからなる第２の初期育成槽５ｂが連通した後期育成槽５５とに仕切る。そして第１の初期育成槽５ａに初期状態の魚介類である体重１ｇ程度の子エビを所定数量投入し、第１の初期育成槽５ａ内で子エビを飼育する。初期状態の子エビは体重が小さいので初期育成槽５ａという狭い容積でも支障なく生育させることができるが、約１ヶ月経過して子エビが体重５ｇ程度の中間状態にまで育成すると、初期育成槽５ａの容積ではこれ以上飼育することは難しい。
【００３４】
そこで、各飼育槽１ａ，１ｂにおいて、室１４ａと室１４ｂの間の仕切り板１０を抜いて外すと共に、室１４ｄと室１４ｅの間に仕切り板１０を差し込むことによって、図１０（ｂ）に示すように、室１４ａからなる第１の初期育成槽５ａと室１４ｂ〜１４ｄからなる共通育成槽７とを連通させた後期育成槽５５を形成すると共に、仕切り壁９と仕切り板１０からなる仕切り部６で室１４ｅからなる第２の初期育成槽５ｂを仕切るようにする。このように第１の初期育成槽５ａと共通育成槽７とを連通させた後期育成槽５５で、第１の初期育成槽５ａで中間状態にまで飼育したエビをさらに飼育することができるものである。ここで、後期育成槽５５は室１４ａ〜１４ｄからなり、室１４ａのみからなる第１の初期育成槽５ａの４倍の容積であるので、後期育成槽５５で中間状態のエビを良好に飼育することができるものである。またこのとき同時に、室１４ｅからなる第２の初期育成槽５ｂに体重１ｇ程度の子エビを所定数量投入し、後期育成槽５５での中間状態のエビの飼育と並行して、第２の初期育成槽５ｂで子エビを育成する。そして約１ヶ月を経過すると、後期育成槽５５内の体重５ｇ程度の中間状態のエビは体重２０ｇ程度の成エビにまで成長し、出荷可能状態に達する。同時に、第２の初期育成槽５ｂ内では子エビは体重５ｇ程度の中間状態にまで育成している。そして、後期育成槽５５内から出荷可能状態に育成した成エビを取り出して出荷することができるものである。
【００３５】
このように各飼育槽１ａ，１ｂにおいて第１の初期育成槽５ａと共通育成槽７とを連通させた後期育成槽５５から成エビを取り出した後、各飼育槽１ａ，１ｂにおいて、室１４ａと室１４ｂの間に仕切り板１０を差し込むと共に、室１４ｄと室１４ｅの間の仕切り板１０を抜いて外すことによって、図１０（ａ）に示すように、室１４ｅからなる第２の初期育成槽５ｂと室１４ｂ〜１４ｄの共通育成槽７とを連通させた後期育成槽５５を形成すると共に、仕切り壁９と仕切り板１０からなる仕切り部６で室１４ａからなる第１の初期育成槽５ａを仕切るようにする。そして第２の初期育成槽５ｂで中間状態にまで飼育したエビを第２の初期育成槽５ｂと共通育成槽７とを連通させた後期育成槽５５で、約１ヶ月を要して出荷可能な成エビにまで育成すると共に、これと並行して、室１４ａからなる第１の初期育成槽５ａに体重１ｇ程度の子エビを所定数量投入し、子エビを中間状態にまで育成する。
【００３６】
上記のようにして、図１０（ｂ）の、室１４ａからなる第１の初期育成槽５ａで初期状態から中間状態にまで育成したエビを、室１４ａ〜１４ｄからなる後期育成槽５５で出荷可能状態の成エビにまで育成すると同時に、室１４ｅからなる第２の初期育成槽５ｂで初期状態の子エビを中間状態にまで育成する段階と、図１０（ａ）の、室１４ｅからなる第２の初期育成槽５ｂで初期状態から中間状態にまで育成したエビを、室１４ｂ〜１４ｅからなる後期育成槽５５で出荷可能状態の成エビにまで育成すると同時に、室１４ａからなる第１の初期育成槽５ａで初期状態の子エビを中間状態にまで育成する段階とを、交互に繰り返すことによって、各飼育槽１ａ，１ｂで初期状態の子エビを出荷可能状態の成エビにまで育成することができるものである。
【００３７】
ここで、クルマエビなどの魚介類を養殖するにあたって、従来は、体重１ｇ程度の子エビを飼育槽に入れ、飼育槽内で子エビが体重２０ｇ程度の成エビにまで育成した後に、飼育槽から成エビを取り出して出荷するのが一般的である。このように体重１ｇ程度の子エビが体重２０ｇ程度の成エビにまで育成するのに必要な期間は、通常２ヶ月程度である。そして、エビなどの魚介類を飼育槽で養殖する場合、飼育槽の容積は魚介類の体重に比例したものが必要であるとされている。例えば、体重２０ｇの成エビを飼育するのに必要な容積は、体重１ｇの子エビの飼育に必要な容積の２０倍である。従って上記のように飼育槽で子エビから出荷可能な成エビにまで育成する場合には、成エビに必要な容積を有する飼育槽を用いる必要があり、飼育槽で子エビを飼育している間は、飼育槽の１／２０の容積しか有効利用していないということになり、飼育槽の使用効率のうえで問題を有する。また、子エビが成エビにまで育成するのに必要な期間は、水温調整などをして理想的な飼育状態に設定したときに２ヶ月程度であるので、設備のメンテナンスに必要な期間を考慮すると、最大年間５回程度しか魚介類を生産することができない。
【００３８】
これに対して、図１０（ａ）（ｂ）のように、狭い容積の初期育成槽５ａ，５ｂで初期状態の魚介類を中間状態にまで育成させる飼育と、中間状態に成長した魚介類を連通させた初期育成槽５ａ，５ｂと共通育成槽７からなる後期育成槽５５の広い容積で出荷可能状態にまで育成させる飼育とを同時に並行して行なうようにすることによって、飼育槽１ａ，１ｂの容積を魚介類の大きさに合わせて効率高く使用して、短い出荷サイクルで魚介類を効率よく生産することができるものである。そして上記のように各段階の所要期間は１ヶ月であるので、毎月、成エビを出荷することができるものであり、設備のメンテナンスに必要な期間を考慮しても、年間１０回エビを生産することができ、従来の約２倍の生産が可能になるものである。
【００３９】
上記のように魚介類を飼育槽１で飼育するにあたって、一般に、魚介類を飼育するのに必要な槽の容積（飼育水の容積）は魚介類の体重に比例するといわれている。そこで本発明の実施の形態では、初期育成槽５に張られる飼育水２の容積と、連通させた初期育成槽５と共通育成槽７からなる後期育成槽５５に張られる飼育水２の容積の比が、中間状態の魚介類の体重と、出荷可能状態の魚介類の体重の比にほぼ等しくなるように、各初期育成槽５と共通育成槽７の大きさを設定するようにしてある。具体的には、初期育成槽５で子エビを体重５ｇ程度の中間状態にまで育成し、さらに連通させた初期育成槽５と共通育成槽７からなる後期育成槽５５で体重２０ｇ程度の出荷可能状態の成エビに育成する場合、後期育成槽５５の容積が初期育成槽５の容積の４倍になるように、飼育槽１を形成するものであり、飼育槽１内を室１４ａ〜１４ｅに５等分して、その一つで初期育成槽５を、他の四つで連通させた初期育成槽５と共通育成槽７からなる後期育成槽５５を形成するようにしてある。
【００４０】
また上記のように、飼育槽１の各室１４ａ〜１４ｅには砂床８が敷設してあるので、魚介類としてエビやその他、砂に潜る習性のあるものを飼育するのに適している。そして飼育槽１の各室１４ａ〜１４ｅは上端が砂床８の上面より上で且つ、飼育水２の水面より下に位置する仕切り壁９で仕切ってあり、この仕切り壁９の上に仕切り板１０を配置することによって、初期育成槽５と共通育成槽７の間の仕切り部６を形成するようにしてあるので、初期状態の魚介類を成育する初期育成槽５と中間状態の魚介類を成育する共通育成槽７とを、仕切り壁９と仕切り板１０からなる仕切り部６で砂床８及び飼育水２の水中の両方において完全に分断することができ、砂床８に潜った魚介類がこの間を移動するようなことを防ぐことができるものである。
【００４１】
ここで、上記のように魚介類１２が砂床８に潜る習性を有する場合、出荷可能状態に成長した魚介類１２を飼育槽１から取り出して出荷するにあたって、魚介類１２を捕獲するのが困難である。そこで本発明では既述のように、砂床８の下に目開きが砂の粒径より大きく、且つ魚介類よりも小さい捕獲用ネット１１が敷いてある。そして図１１（ａ）のように飼育槽１の側壁の上に突出させた捕獲用ネット１１の端部を引くと、目開きが砂の粒径より大きい捕獲用ネット１１は砂床８内を通過して引き上げられるので、図１１（ｂ）に示すように、飼育槽１の飼育水２中を遊泳する魚介類１２は勿論、砂床８に潜っていた魚介類１２も捕獲用ネット１１の上に捕獲することができるものであり、一匹も逃がすことなく捕獲して取り出すことができるものである。
【００４２】
このとき、図１２に示すように、捕獲用ネット１１を複数枚重ねて砂床８の下側に張るようにし、出荷可能状態に成長した魚介類１２を飼育槽１から取り出して出荷する際に、上から１枚ずつ捕獲用ネット１１を引き上げて魚介類１２の捕獲を行なうようにすることによって、魚介類１２を飼育槽１から取り出して出荷する度に、砂床８の下に捕獲用ネット１１を張り直すような必要がなくなるものである。
【００４３】
【発明の効果】
上記のように本発明の請求項１に係る魚介類の養殖システムは、底部に砂床を設けた魚介類飼育用の飼育槽と、飼育槽の飼育水を浄化する飼育水浄化手段と、飼育水を飼育槽と飼育水浄化手段の間で循環させる循環手段とを備えた魚介類の養殖システムにおいて、飼育槽の一端部に異物排出口を設けると共に、異物排出口と対向する他端部に異物排出口へ向けて水流を発生させる水流発生手段を設け、砂床上の水位を下げた後に水流発生手段で水流を発生させて、砂床上の異物を水流で異物排出口に排出するようにしたので、砂床上の水位が低く強い勢いの水流で砂床上の異物を洗い流すことができ、砂床上の異物が大きな固形異物であっても効率よく異物排出口から排出して清掃することができるものである。
【００４４】
また請求項２の発明は、請求項１において、飼育槽の側壁に砂床の上面よりやや上方位置において異物排出口を設けると共に異物排出口より上側位置において飼育槽内の飼育水を流出させる排水口を設け、排水口を循環手段に接続するようにしたので、水流で砂床上の異物を洗い流すにあたって、異物は砂床の上面よりやや上方位置の異物排出口に流れ込み、異物排出口の上側に配置される排水口には流れ込むことがないものであり、異物が排水口から循環手段に流入してしまうことを防ぐことができるものである。
【００４５】
また請求項３の発明は、請求項１又は２において、水とともに異物排出口に排出される異物を貯溜する貯溜水槽を具備するので、貯溜水槽内で異物を沈降させた後にその上澄み部分の飼育水をシステムに返送して養殖に再使用することができるものであり、システムに補充する飼育水の量を低減することができるものである。
【００４６】
また請求項４の発明は、請求項１乃至３のいずれかにおいて、上端が砂床の上面より上で且つ、飼育水の水面より下に位置する仕切り壁を飼育槽内に複数設け、隣り合う各仕切り壁間において異物排出口と水流発生手段とを対向させて設けるようにしたので、水流発生手段からの水流は両側の仕切り壁でガイドされて横に広がるようなことがなく、砂床上の異物を効率よく洗い流して異物排出口に排出することができるものである。
【００４７】
また請求項５の発明は、請求項１乃至４のいずれかにおいて、飼育槽を一対設けると共に各飼育槽を循環手段で接続し、一方の飼育槽内の飼育水を循環手段を通じて他方の飼育槽へ送ることによって、一方の飼育槽の砂床上の水位を下げるようにしたので、システム内での飼育水の移動で飼育槽の砂床上の水位を下げることができ、飼育槽の砂床上の水位を下げるにあたって、システム外へ飼育水を排出するような必要がなくなるものである。
【００４８】
また請求項６の発明は、請求項５において、各飼育槽に設けた水流発生手段をそれぞれ循環手段に接続し、一方の飼育槽内の飼育水を循環手段を通じて他方の飼育槽へ送ることによって、一方の飼育槽の砂床上の水位を下げると共に他方の飼育槽の水位を上昇させた後、この水位の差によって他方の飼育槽内の飼育水を循環手段を通じて一方の飼育槽に設けた水流発生手段に送ると共に水流発生手段から吐出させて水流を発生させるようにしたので、一方の飼育槽の砂床上の水位を下げる際の、両飼育槽の水位の差を利用して、水流発生手段から飼育水を吐出させて水流を発生させることができ、水流を発生させるための動力等が不要になるものである。
【００４９】
また請求項７の発明は、請求項１乃至６のいずれかにおいて、砂床の下側に砂の粒径より大きい目を有する捕獲用ネットを張設し、捕獲用ネットを砂床の上方へ引き上げることによって、捕獲用ネットの上に魚介類を捕獲するようにしたので、飼育槽の飼育水中を遊泳する魚介類は勿論、砂床に潜っている魚介類も捕獲用ネットの上に捕獲することができるものであり、魚介類を逃がすことなく捕獲することができるものである。
【００５０】
また請求項８の発明は、請求項７において、捕獲用ネットを複数枚重ねて砂床の下側に張設し、上から１枚ずつ捕獲用ネットを引き上げるようにしたので、捕獲用ネットを引き上げて魚介類の捕獲を操作を複数回行なうことができるものであり、魚介類を飼育槽から取り出して出荷する度に、砂床の下に捕獲用ネットを張り直すような必要がなくなるものである。
【図面の簡単な説明】
【図１】本発明の実施の形態の一例における飼育槽を短手方向に切断した拡大断面図である。
【図２】本発明の実施の形態の一例を示す平面図である。
【図３】同上の斜視図である。
【図４】同上の飼育槽を長手方向に切断した断面図である。
【図５】同上の飼育槽の網板部分を示すものであり、（ａ）は正面図、（ｂ）は平面図である。
【図６】同上の飼育槽内の異物の清掃を行なう状態を示すものであり、（ａ），（ｂ）はそれぞれ概略断面図である。
【図７】同上の飼育槽内の異物の清掃を行なう際の開閉弁の開閉状態を示す平面図である。
【図８】同上の飼育槽内の異物の清掃を行なう際の開閉弁の開閉状態を示す平面図である。
【図９】同上の飼育槽内の異物の清掃を行なう際の開閉弁の開閉状態を示す平面図である。
【図１０】同上の魚介類の飼育の状態を示すものであり、（ａ），（ｂ）はそれぞれ概略平面図である。
【図１１】同上の魚介類を捕獲して飼育槽から取り出す状態を示すものであり、（ａ），（ｂ）はそれぞれ断面図である。
【図１２】同上の魚介類を捕獲して飼育槽から取り出す状態の他例を示す断面図である。
【図１３】同上の養殖システムの構成を示す概略図である。
【符号の説明】
１飼育槽
２飼育水
３飼育水浄化手段
４循環手段
８砂床
９仕切り壁
１１捕獲用ネット
１２魚介類
１３水流発生手段
２９排水口
３０異物排出口
３３貯溜水槽[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for removing foreign substances on a sand bed of a breeding tank in a fish and shellfish culturing system in which fish and shellfish such as shrimp and fish are cultivated in a breeding tank while circulating and recycling the breeding water. It is.
[0002]
[Prior art]
2. Description of the Related Art Various systems have been conventionally proposed for cultivating fish and shellfish at a high density in a breeding tank by purifying and circulating breeding water in the breeding tank. When cultivating seafood such as shrimp having the habit of diving in sand, sand is laid on the bottom of the breeding tank to form a sand bed (for example, see Patent Document 1).
[0003]
There is a cultivation system in which a sand bed is formed at the bottom of such a breeding tank, and solid foreign matters such as shrimp shells and remaining food tend to remain on the sand bed. Therefore, in Patent Literature 1, a water flow is allowed to pass upward from a lower side to a sand bed so as to float foreign matters, and to remove the floated foreign matters to the outside of the breeding tank.
[0004]
[Patent Document 1]
JP-A-2002-159241
[0005]
[Problems to be solved by the invention]
However, in the case where the water flow is passed upward from the bottom to the sand bed to suspend foreign matter, it is necessary to pass a gentle water flow to the sand bed so that the sand on the sand bed does not fly up. With a gentle water flow, it is difficult to float large solid foreign matters such as shells and bait remaining on the sand bed, and there is a problem that large foreign matters on the sand bed cannot be sufficiently removed. Was something.
[0006]
The present invention has been made in view of the above points, and has as its object to provide a fish and shellfish cultivation system that can efficiently remove and clean large foreign matters on a sand bed of a breeding tub. It is.
[0007]
[Means for Solving the Problems]
The cultivation system for fish and shellfish according to claim 1 of the present invention comprises a breeding tank 1 for breeding seafood having a sand bed 8 at the bottom, a breeding water purification means 3 for purifying breeding water 2 in the breeding tank 1, In a fish and shellfish culturing system provided with a circulating means 4 for circulating the breeding water 2 between the breeding tank 1 and the breeding water purifying means 3, a foreign substance discharge port 30 is provided at one end of the breeding tank 1 and a foreign substance discharge port is provided. A water flow generating means 13 for generating a water flow toward the foreign matter discharge port 30 is provided at the other end facing the foreign matter 30. After the water level on the sand bed 8 is lowered, a water flow is generated by the water flow generating means 13 and The above foreign matter is discharged to the foreign matter discharge port 30 by a water flow.
[0008]
According to the second aspect of the present invention, the foreign matter discharge port 30 is provided on the side wall of the breeding tub 1 at a position slightly above the upper surface of the sand bed 8 and the breeding in the breeding tub 1 at a position above the foreign substance discharge port 30. A drain port 29 through which the water 2 flows out is provided, and the drain port 29 is connected to the circulation means 4.
[0009]
A third aspect of the present invention is characterized in that, in the first or second aspect, a storage water tank 33 for storing foreign matter discharged to the foreign matter discharge port 30 together with water is provided.
[0010]
According to the invention of claim 4, in any one of claims 1 to 3, a plurality of partition walls 9 whose upper end is located above the upper surface of the sand bed 8 and below the surface of the breeding water 2 are provided in the breeding tub 1. It is characterized in that the foreign matter discharge port 30 and the water flow generating means 13 are provided so as to face each other between adjacent partition walls 9.
[0011]
The invention of claim 5 is the invention according to any one of claims 1 to 4, wherein a pair of breeding tubs 1 is provided, and each breeding tub 1 is connected by a circulating means 4, and breeding water 2 in one breeding tub 1 is circulated by a circulating means. The water level on the sand bed 8 of one of the breeding tubs 1 is lowered by being sent to the other breeding tub 1 through 4.
[0012]
According to the invention of claim 6, in claim 5, the water flow generating means 13 provided in each breeding tub 1 is connected to the circulating means 4, respectively, and the breeding water 2 in one breeding tub 1 is passed through the circulating means 4 to the other. After being sent to the breeding tub 1, the water level on the sand bed 8 of one breeding tub 1 is lowered and the water level of the other breeding tub 1 is raised. 2 is sent to the water flow generation means 13 provided in one of the breeding tanks 1 through the circulation means 4 and discharged from the water flow generation means 13 to generate a water flow.
[0013]
The invention of claim 7 is the invention according to any one of claims 1 to 6, wherein a catching net 11 having an eye larger than the grain size of the sand is stretched below the sand bed 8, and the catching net 11 is placed on the sand bed. The fish and shellfish are caught on the catching net 11 by being pulled up above the catching net 8.
[0014]
According to an eighth aspect of the present invention, in the seventh aspect, a plurality of the catching nets 11 are stacked and stretched under the sand bed 8, and the catching nets 11 are pulled up one by one from above. It is a feature.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0016]
FIG. 13 shows a schematic configuration of the aquaculture system. The breeding tank 1 for breeding fish and shellfish, breeding water purification means 3 for purifying breeding water 2 in the breeding tank 1, and breeding water 2 are bred to the breeding tank 1. A circulation means 4 for circulating between the water purification means 2 is provided. In the system of FIG. 13, the breeding water purification means 3 is formed by the sedimentation tank 15, the biological treatment filtration tank 16, and the ultraviolet sterilization tank 17, and the circulation means 4 is formed by the piping connecting the tanks and the pump 18. It is like that. In this aquaculture system, the water in the breeding tub 1 is circulated in a closed cycle by a pump 18, and the breeding water 2 in the breeding tub 1 first flows into the sedimentation tub 15 and the SS generated in the breeding tub 1. Solids such as waste, excrement, and remaining food are separated from the breeding water 2 by natural sedimentation and cyclone water flow and removed. The biological treatment filter tank 16 is filled with a filter medium to which microorganisms have adhered, and when the breeding water 2 that has passed through the sedimentation tank 15 flows into the biological treatment filter tank 16, ammonia generated from the excrement of fish and shellfish causes nitrification of the microorganisms. Decomposed to nitric acid by the reaction. The fine SS that cannot be removed in the sedimentation tank 15 is removed by filtration in the biological treatment filtration tank 16. The breeding water 2 that has passed through the biological treatment filtration tank 16 is irradiated with ultraviolet rays in an ultraviolet sterilization tank 17 to kill harmful microbial bacteria. The breeding water 2 thus purified in the sedimentation tank 15, the biological treatment filtration tank 16, and the ultraviolet sterilization tank 17 is returned to the breeding tank 1 by the pump 18.
[0017]
The breeding tub 1 is formed in an elongated rectangular shape as shown in FIGS. 2 and 3, and partition walls 9 are provided at regular intervals from the bottom surface so as to partition the breeding tub 1 at regular intervals in the longitudinal direction. It is. As shown in FIG. 4, the partition wall 9 is formed at a height such that the upper end is lower than the surface of the breeding water 2 in the breeding tub 1. In the embodiment shown in FIG. The breeding tub 1 is partitioned into five chambers 14a to 14e. At the bottom of each of the chambers 14a to 14e, a gantry 21 provided with legs 20 on the lower surface is installed as shown in FIG. The gantry 21 is formed of a through hole, a perforated pallet, or the like, provided with a large number of through holes 22 through which water can freely pass vertically. A base net 23 having an opening smaller than the particle size of the sand on the sand bed 8 is laid on the gantry 21, and the catching net 11 is further laid on the base net 23. The size of the opening of the capture net 11 is set to a size larger than the particle size of the sand on the sand bed 8 and smaller than the size of the fish and shellfish bred in the breeding tank 1 when shipped. Sand is scattered on the catching net 11 to form a sand bed 8. The sand bed 8 is formed so that the upper surface is slightly below the upper end of the partition wall 9.
[0018]
Among the partition walls 9 provided in the breeding tub 1, a partition plate 10 is provided above the partition walls 9 located at both ends in the longitudinal direction of the breeding tub 1. The partition plate 10 is mounted on the partition wall 9 by inserting both ends between a pair of parallel guide plates 24 provided on each inner surface of the longitudinal side wall of the breeding tub 1. The partition plate 10 can be removed by extracting it upward from the space between the two. The upper end of the partition plate 10 mounted on the partition wall 9 projects above the water surface of the breeding water 2 in the breeding tub 1, and the partition portion 6 is formed by the partition plate 10 and the partition wall 9. The interior of the breeding tub 1 is divided into three tubs by the partition 6 and the initial breeding tub 5 is formed by the chambers 14a and 14e at both ends, and the common breeding tub 7 is formed by the central chambers 14b to 14d. It can be formed. The breeding tub 1 thus formed is used in pairs, and one breeding tub 1a and the other breeding tub 1b are arranged on both sides of the breeding water purification means 3 at the same height level.
[0019]
A drain gutter 26 is provided on the outer surface of the side wall of the breeding tank 1 on the side of the breeding water purification means 3 along substantially the entire length in the longitudinal direction. As shown in FIG. And a cleaning drainage chamber 28 at the bottom, and is divided into upper and lower two-stage chambers. In each of the chambers 14a to 14e of the breeding tub 1, a drain port 29 formed in the upper part of the side wall is opened to the drain chamber 27. In each of the chambers 14a to 14e, a foreign substance discharge port 30 formed in the lower part of the side wall is cleaned. The drainage chamber 28 is open. The drain outlet 29 is arranged at a height near the water surface of the breeding water 2 in the breeding tub 1, and the foreign matter outlet 30 is arranged at a position slightly higher than the upper surface of the sand bed 8. The drainage chamber 27 of the drainage gutter 26 is connected to the sedimentation tank 15 by a return pipe 31, and the cleaning drainage chamber 28 is connected by a cleaning pipe 32 to a storage water tank 33 arranged and arranged in the same way as the breeding water purification means 3. It is. As shown in FIG. 1, the drainage chamber 27 of one breeding tub 1a of the pair of breeding tubs 1 is settled by a return pipe 31a, and the drainage chamber 27 of the other breeding tub 1b is settled by a return pipe 31b. It is connected to the tank 15. The cleaning drainage chamber 28 of one breeding tub 1a is connected to the storage water tank 33 by a cleaning pipe 32a, and the cleaning drainage chamber 28 of the other breeding tub 1b is connected by a cleaning pipe 32b.
[0020]
Further, a mesh plate 35 is provided on the inner surface of the side wall of each of the chambers 14a to 14e so as to cover the drainage port 29 and the foreign matter discharge port 30 formed in the breeding tub 1 as described above. The mesh plate 35 is formed by stretching a mesh 36 at the opening, and the drain 36 and the foreign matter outlet 30 are covered with the mesh 36 as shown in FIG. The size of the mesh of the mesh 36 is smaller than the size of the fish and shellfish to be cultivated, and is set to be larger than solid foreign matters such as residual food and moulting shells generated in the breeding tank 1. The mesh plate 35 is vertically slidable by inserting both ends thereof into a pair of guide rails 37 provided on the inner surface of the side wall of the breeding tub 1. The mesh plate 35 has a vertically long slot 38 provided at the upper end of the mesh plate 35. The mesh plate 35 is fixed by the fixing bolts 39 by screwing into the side wall of the breeding tub 1 through the fixing bolts 39. By loosening the fixing bolt 39, the height of the mesh plate 35 can be adjusted within the range of the vertical length of the long hole 38. The height is adjusted so that the lower end of the mesh plate 35 is buried in the sand bed 8. It is made to do.
[0021]
In each of the chambers 14a to 14e of the breeding tub 1, a recess 41 is formed at the bottom of the breeding tub 1, and a water supply port 42 is formed at the center of the recess 41 as shown in FIG. A branch water supply pipe 44 branched from a water supply pipe 43 connected to the pump 18 is connected to the water supply port 42, and a baffle plate fixed to the bottom of the breeding tub 1 with legs 45 at a position above the water supply port 42. 46 are arranged. Further, a discharge pipe 47 is disposed in each of the chambers 14a to 14e on the inner side of the side wall of the breeding tub 1 opposite to the side where the drain gutter 26 is provided. The discharge pipe 47 is horizontally arranged near the upper surface of the sand bed 8 in parallel with the side wall of the breeding tub 1, and the discharge pipe 47 has a discharge port 48 opening toward the foreign matter discharge port 30 in the longitudinal direction. It is provided at a plurality of locations. The water flow generating means 13 is formed by the discharge pipe 47 provided with the discharge port 48. A discharge pipe 49 branched from the water supply pipe 43 is connected to the discharge pipe 47, and the discharge pipe 49 is bent in an inverted U shape so as to ride over the side wall of the breeding tub 1 and to be connected to the discharge pipe 47. is there. As shown in FIG. 2, a water supply pipe 43a is connected to one of the breeding tanks 1a and 1b, and a branch water supply pipe 44a is connected to the water supply port 42. A water supply pipe 43b is connected to the other rearing tank 1b, and a branch water supply pipe 44b is connected to the water supply port. A discharge pipe 49a is connected to the discharge pipe 47 of one breeding tub 1a, and a discharge pipe 49b is connected to the discharge pipe 47 of the other breeding tub 1b.
[0022]
A connection pipe 51 for connecting the settling tank 15 to the biological treatment filtration tank 16 and the ultraviolet sterilization tank 17, a connection pipe 52 for connecting the ultraviolet sterilization tank 17 to the pump 18, and the return pipes 31 a and 31 b and the water supply pipe 43 a. 43b, a pipe of the circulation means 4 is formed by the water supply branch pipes 44a, 44b. Then, as shown in FIG. 2, the water supply pipes 43a and 43b, the water supply branch pipes 44a and 44b, the return pipes 31a and 31b, the cleaning pipes 32a and 32b, and the discharge pipes 49a and 49b are each formed by an electromagnetic valve or the like. Open / close valves 53a to 53j are provided.
[0023]
In the aquaculture system formed as described above, during normal operation of culturing fish and shellfish in the breeding tanks 1a and 1b, the on-off valves 53a and 53b of the water supply pipes 43a and 43b, and the on-off valves of the water supply branch pipes 44a and 44b. 53c, 53d, the open / close valves 53e, 53f of the return pipes 31a, 31b were opened, and the open / close valves 53g, 53h of the cleaning pipes 32a, 32b, and the open / close valves 53i, 53j of the discharge pipes 49a, 49b were closed. The pump 18 is operated in this state, and the breeding water 2 purified by the breeding water purifying means 3 is sent from the water supply pipes 43a and 43b to the water supply branch pipes 44a and 44b, and the breeding tank 1a and 1b Is supplied from the water supply port 42. At this time, as shown by the arrow A in FIG. 1, the breeding water 2 blown upward from the water supply port 42 hits the lower surface of the baffle plate 46, and flows uniformly in the breeding tanks 1a and 1b in a state of being dispersed in four directions. It has become. The breeding water 2 in the breeding tanks 1a and 1b is maintained at a constant water level by flowing water near the water surface from a drain port 29 into a drain chamber 27 of a drain gutter 26. The breeding water 2 flowing into the drainage chamber 27 is discharged from the return pipes 31a and 31b, sent to the sedimentation tank 15, and purified by the breeding water purification means 3.
[0024]
When seafood is cultivated in the breeding tanks 1a and 1b as described above, solid foreign substances such as shells of the seafood and residual food are accumulated on the sand bed 8, and it is necessary to remove them. Hereinafter, the cleaning operation for removing the solid foreign matter will be described.
[0025]
First, in the above-described normal culture operation, as shown in FIG. 7, an on-off valve 53a of a water supply pipe 43a connected to the breeding tank 1a and an on-off valve of a return pipe 31b connected to the breeding tank 1b. 53f is closed (in FIG. 7, the open / closed valve in the open state is shown in white, and the open / closed valve in the closed state is shown in black. The same applies to FIGS. 8 and 9). Therefore, the open / close valve 53b of the water supply pipe 43b connected to the breeding tank 1b, the open / close valves 53c and 53d of the water supply branch pipes 44a and 44b, and the open / close valve 53e of the return pipe 31a connected to the breeding tank 1a are open. The on-off valves 53g and 53h of the cleaning pipes 32a and 32b and the on-off valves 53i and 53j of the discharge pipes 49a and 49b are closed. When the pump 18 is operated in this state, the breeding tank 1b is supplied with the breeding water 2 through the water supply pipe 43b and the water supply branch pipe 44b, but the return pipe 31b of the breeding tank 1b is closed. The breeding water 2 is not discharged from the breeding tub 1b, and the water level of the breeding water 2 in the breeding tub 1b rises as compared with the normal culturing operation, as shown in FIG. On the other hand, the breeding tub 1a is not supplied with the breeding water 2 because the water supply pipe 43a is closed, but the breeding water 2 in the breeding tub 1a is discharged from the breeding tub 1a because the breeding water 2 is not supplied to the breeding tub 1a. When the water flows into the drainage chamber 27, the water is drained from the return pipe 31a to the sedimentation tank 15, and the level of the breeding water 2 in the breeding tank 1a drops as shown in FIG.
[0026]
When the level of the breeding water 2 in the breeding tub 1a drops to a predetermined height (for example, 5 cm from the upper surface of the sand bed 8), the operation of the pump 18 is stopped by controlling a float switch or the like, and as shown in FIG. The open / close valve 53b of the water supply pipe 43b connected to the tank 1b and the open / close valve 53e of the return pipe 31a of the breeding tub 1a are closed, and the open / close valve 53g of the cleaning pipe 32a of the breeding tub 1a is opened. By opening the cleaning pipe 32a of the breeding tub 1a in this manner, the breeding water 2 in the cleaning drainage chamber 28 of the breeding tub 1a is discharged to the storage water tank 33, so that the sand bed of the breeding tub 1a whose water level is lowered. The breeding water 2 on 8 flows into the cleaning drainage chamber 28 from the foreign substance discharge port 30, and along with this flow, solid foreign substances on the sand bed 8 also flow into the cleaning drainage chamber 28 from the foreign substance discharge port 30. The solid foreign matter that has flowed into the cleaning drain chamber 28 is discharged together with the breeding water 2 into the storage water tank 33 through the cleaning pipe 32a.
[0027]
When the water level of the breeding water 2 in the breeding tub 1a is further lowered by being discharged to the storage water tank 33 in this way, and reaches a position slightly above the foreign matter discharge port 30 as shown by a two-dot chain line in FIG. As shown, the open / close valves 53a and 53b of the water supply pipes 43a and 43b are opened, the open / close valve 53c of the water supply branch pipe 44a of the breeding tub 1a is closed, and the open / close valve 53i of the discharge pipe 49a of the breeding tub 1a is opened. Then, the water supply branch pipe 44b of the breeding tub 1b and the discharge pipe 49a of the breeding tub 1a communicate with each other through the water supply pipes 43a and 43b, and the water level of the breeding water 2 in the breeding tub 1b as shown in FIG. Is higher than the water level of the breeding water 2 in the breeding tub 1a, the breeding water 2 in the breeding tub 1b flows out of the water supply port 42 to the water supply branch pipe 44b due to the difference in the water level, and the water supply pipe 43b and the water supply pipe The breeding water 2 is discharged from a discharge pipe 49a of the breeding tub 1a after passing through the tubing 43a.
[0028]
In this manner, the breeding water 2 is discharged from the discharge port 48 of the discharge pipe 47 toward the foreign substance discharge port 30 as shown by the arrow B in FIG. The foreign matter can be allowed to flow into the cleaning drain chamber 28 from the foreign matter discharge port 30, and the solid foreign matter can be discharged to the storage water tank 33 through the cleaning pipe 32a. At this time, since the water level of the breeding water 2 on the sand bed 8 in the breeding tub 1a is low, a strong water flow can be generated by discharging the breeding water 2 from the discharge pipe 47. The solid foreign matter on the floor 8 can be efficiently washed away with a high current of water. Here, since the foreign substance discharge port 30 is covered with the mesh 36, the bred fish and shellfish cannot enter the foreign substance discharge port 30, but foreign substances such as shells and remaining foods pass through the mesh 36 to discharge the foreign substance. It can be discharged from the outlet 30.
[0029]
Although solid foreign matters remaining on the sand bed 8 of one breeding tub 1a can be cleaned as described above, cleaning of the other breeding tub 1b can be performed according to the above-described operation. That is, first, the on-off valve 53b of the water supply pipe 43b connected to the breeding tub 1b and the on-off valve 53e of the return pipe 31a connected to the breeding tub 1a are closed, and in this state, the pump 18 is operated. As shown in (b), the water level of the breeding water 2 in the breeding tub 1a is higher than that in the normal culturing operation, and the water level of the breeding water 2 in the breeding tub 1b is lower. Next, the operation of the pump 18 is stopped, the on-off valve 53a of the water supply pipe 43a connected to the breeding tub 1a and the on-off valve 53f of the return pipe 31b of the breeding tub 1b are closed, and the cleaning pipe 32b of the breeding tub 1b is closed. Is opened. By opening the cleaning pipe 32b in this manner, the breeding water 2 in the breeding tub 1b, whose water level has dropped, flows into the cleaning drainage chamber 28 through the foreign substance discharge port 30, and solid foreign matter on the sand bed 8 is also removed with this flow. The water flows into the cleaning drain chamber 28 and is discharged to the reservoir 33 through the cleaning pipe 32b. When the water level of the breeding water 2 in the breeding tub 1b further decreases to the position shown by the two-dot chain line in FIG. 1, the open / close valves 53a and 53b of the water supply pipes 43a and 43b are opened to supply water to the breeding tub 1b. The on-off valve 53d of the branch pipe 44b is closed and the on-off valve 53j of the discharge pipe 49b of the breeding tub 1b is opened. Then, as shown in FIG. 6 (b), the water level of the breeding water 2 in the breeding tub 1a is higher than the water level of the breeding water 2 in the breeding tub 1b. 2 flows out of the water supply port 42 to the water supply branch pipe 44a, passes through the water supply pipe 43a and the water supply pipe 43b, is sent to the discharge pipe 49b of the breeding tub 1b, and is discharged from the discharge pipe 47 arranged in the breeding tub 1b. The breeding water 2 is discharged from 48 toward the foreign matter discharge port 30 as shown by the arrow B in FIG. 1, and the solid foreign matter on the sand bed 8 is washed away with a water flow, and then flows into the cleaning drain chamber 28 from the foreign matter discharge port 30. The solid foreign matter can be discharged to the storage water tank 33 through the cleaning pipe 32b.
[0030]
Here, as shown in FIG. 4, the breeding tub 1 is partitioned by a partition wall 9 protruding from the upper surface of the sand bed 8, and a discharge pipe 47 forming the water flow generating means 13 is disposed between the adjacent partition walls 9. I have. Therefore, when the breeding water 2 is discharged from the discharge port 48 of the discharge pipe 47 and the solid foreign matter on the sand bed 8 is washed away with the water flow, the water flow is not guided and spread by the partition walls 9 on both sides. The solid foreign matter on the sand bed 8 can be efficiently washed out and discharged from the foreign matter discharge port 30 into the cleaning drainage chamber 28.
[0031]
Further, among the discharge pipes 47 arranged in the respective chambers 14a to 14b of the breeding tub 1, the open / close valve 53i (53j) of the discharge pipe 47 of one room is opened, and the open / close valve 53i (53j) of the discharge pipe 47 of the other room. Is closed, the breeding water 2 can be discharged from one discharge pipe 47 in a concentrated manner, and the solid foreign matter on the sand bed 8 can be efficiently washed away by a strong water flow. At this time, since each of the chambers 14a to 14b is partitioned by the partition wall 9 protruding from the upper surface of the sand bed 8 as described above, the breeding water 2 is supplied from the discharge pipe 47 while the other discharge pipe 47 is closed. In the case of discharging, it is possible to prevent the breeding water 2 discharged from the discharge pipe 47 from spreading to another room by the partition wall 49, and it is possible to cause a strong water flow by concentrating in one room. Thus, foreign matter on the sand bed 8 in this room can be efficiently removed.
[0032]
The breeding water 2 containing the solid foreign matter that has flowed into the storage water tank 33 as described above, after the solid foreign matter is naturally precipitated, the supernatant portion is returned to the breeding tank 1 or the breeding water purification means 3 by a separate pump. Reused for aquaculture. Therefore, the amount of the breeding water 2 to be replenished to the aquaculture system can be minimized. The settled solid foreign matter is decomposed by a garbage disposer or the like. In addition, the storage water tank 33 is used for temporarily storing the breeding water 2 containing the solid foreign matters and for separating and separating the solid foreign matters, and also for washing the sand on the sand bed 8 with sodium hypochlorite or the like. It can also be used for other purposes.
[0033]
Next, a method of cultivating seafood in the breeding tanks 1a, 1b while circulating the breeding water 2 between the breeding tanks 1a, 1b and the breeding water purifying means 3 as described above will be described. Will be described. First, in each of the breeding tanks 1a and 1b, the partition plate 10 between the chambers 14a and 14b is left, and the partition plate 10 between the chambers 14d and 14e is removed and removed, as shown in FIG. As described above, the inside of each breeding tub 1a, 1b is divided into the first initial breeding tub 5a composed of the chamber 14a and the common breeding tub 7 composed of the chambers 14b to 14d by the partition part 6 composed of the partition wall 9 and the partition plate 10. The second initial growth tank 5b composed of 14e is partitioned into a second-stage growth tank 55 that communicates with the second initial growth tank 5b. Then, a predetermined amount of shrimp having a body weight of about 1 g, which are fish and shellfish in an initial state, are put into the first initial breeding tank 5a, and the shrimp are bred in the first initial breeding tank 5a. Since the shrimp in the initial state have a small weight, they can be grown without any problem even in the small volume of the initial growing tank 5a. However, when the shrimp are grown to an intermediate state of about 5 g in weight after about one month, the initial growing tank is not used. It is difficult to breed any more with a volume of 5a.
[0034]
Therefore, in each of the rearing tanks 1a and 1b, the partition plate 10 between the chambers 14a and 14b is pulled out and removed, and the partition plate 10 is inserted between the chambers 14d and 14e, as shown in FIG. As described above, the late growth tank 55 in which the first initial growth tank 5a formed of the chamber 14a communicates with the common growth tank 7 formed of the chambers 14b to 14d is formed, and the partition part formed by the partition wall 9 and the partition plate 10 is formed. At 6, the second initial growth tank 5b composed of the chamber 14e is partitioned. In the latter stage growing tank 55 in which the first initial growing tank 5a communicates with the common growing tank 7, the shrimp bred to an intermediate state in the first initial growing tank 5a can be further raised. is there. Here, the late growth tank 55 is composed of the chambers 14a to 14d, and has a capacity four times as large as that of the first initial growth tank 5a composed of only the chamber 14a. Is what you can do. Simultaneously, at the same time, a predetermined amount of shrimp having a weight of about 1 g is put into the second initial breeding tank 5b composed of the chamber 14e. The shrimp are raised in the raising tank 5b. After about one month, the shrimp in the intermediate state in the late breeding tub 55 having a body weight of about 5 g grows to a mature shrimp having a body weight of about 20 g, and reach a ready-to-ship state. At the same time, the shrimp are grown to an intermediate state of about 5 g in the second initial growth tank 5b. Then, the grown shrimp grown in a shippable state can be taken out from the late growing tank 55 and shipped.
[0035]
In this way, after the adult shrimp is taken out from the late breeding tub 55 in which the first initial breeding tub 5a and the common breeding tub 7 are communicated with each other in the breeding tubs 1a and 1b, the room 14a and the By inserting the partition plate 10 between the chambers 14b and removing and removing the partition plate 10 between the chambers 14d and 14e, as shown in FIG. 10 (a), a second initial growth tank comprising the chamber 14e. 5b and a later-stage breeding tank 55 in which the common breeding tub 7 of the chambers 14b to 14d communicate with each other, and a first initial breeding tub 5a formed of the chamber 14a is formed by the partition 6 formed by the partition wall 9 and the partition plate 10. Try to partition. The shrimp bred to an intermediate state in the second initial breeding tank 5b can be shipped in about one month in the latter breeding tub 55 in which the second initial breeding tub 5b and the common breeding tub 7 are connected. Along with this, shrimp with a weight of about 1 g are put into the first initial growing tank 5a composed of the chamber 14a, and the shrimp are grown to an intermediate state.
[0036]
As described above, the shrimp grown from the initial state to the intermediate state in the first initial growth tank 5a composed of the chamber 14a in FIG. 10B can be shipped in the late growth tank 55 composed of the chambers 14a to 14d. At the same time as growing the grown shrimp to the state, the second initial growing tank 5b consisting of the chamber 14e grows the shrimp in the initial state to the intermediate state, and the second growing step shown in FIG. Of the shrimp grown from the initial state to the intermediate state in the initial growing tank 5b of the above-mentioned state, is grown to a grown shrimp in a shipping state in the late growing tank 55 including the chambers 14b to 14e, and at the same time, the first initial growing of the chamber 14a is performed. By alternately repeating the step of growing the shrimp in the initial state to the intermediate state in the tank 5a, it is possible to grow the shrimp in the initial state to adult shrimp in a shippable state in each of the breeding tanks 1a and 1b. Can also It is.
[0037]
Here, when cultivating fish and shellfish such as prawns, conventionally, a shrimp having a weight of about 1 g is placed in a breeding tank, and after growing the shrimp to an adult shrimp weighing about 20 g in the breeding tank, It is common to take out the shrimp and ship it. Thus, the period required for a shrimp weighing about 1 g to grow to a mature shrimp weighing about 20 g is usually about two months. When cultivating fish such as shrimp in a breeding tank, it is said that the capacity of the breeding tank must be proportional to the weight of the fish and shellfish. For example, the volume required to breed an adult shrimp weighing 20 g is 20 times the volume required to breed a shrimp weighing 1 g. Therefore, when growing from shrimp to adult shrimp that can be shipped in the breeding tank as described above, it is necessary to use a breeding tank having the volume required for adult shrimp, and breeding the shrimp in the breeding tank In the meantime, only 1/20 of the capacity of the breeding tank is effectively used, and there is a problem in the efficiency of use of the breeding tank. In addition, the period required for rearing shrimp to mature shrimp is about two months when water temperature is adjusted and ideal breeding conditions are set, so the period required for equipment maintenance should be considered. Then, the fish and shellfish can be produced only up to about five times a year.
[0038]
On the other hand, as shown in FIGS. 10 (a) and 10 (b), breeding in which the initial state fish and shellfish are grown to an intermediate state in the small initial breeding tanks 5a and 5b, The rearing tanks 1a, 1b are simultaneously bred by raising the large-capacity initial culturing tanks 5a, 5b and the common rearing tub 7 to a state in which they can be shipped in a large capacity. Can be efficiently used in accordance with the size of fish and shellfish to efficiently produce seafood in a short shipping cycle. Since the required time for each stage is one month as described above, the shrimp can be shipped every month, and even if the period required for equipment maintenance is taken into account, shrimp is produced ten times a year. And the production can be made about twice as much as the conventional one.
[0039]
When breeding fish and shellfish in the breeding tank 1 as described above, it is generally said that the volume of the tub required for breeding fish and shellfish (the volume of breeding water) is proportional to the weight of the fish and shellfish. Therefore, in the embodiment of the present invention, the volume of the breeding water 2 stretched in the initial breeding tub 5 and the volume of the breeding water 2 stretched in the late breeding tub 55 composed of the initial breeding tub 5 and the common breeding tub 7 communicated with each other. The sizes of the initial breeding tubs 5 and the common breeding tub 7 are set such that the ratio is substantially equal to the weight of the seafood in the intermediate state and the weight of the seafood in the ready-to-ship state. Specifically, the shrimp are grown in the initial breeding tank 5 to an intermediate state of about 5 g in weight, and can be shipped with a weight of about 20 g in the late breeding tub 55 composed of the initial breeding tub 5 and the common breeding tub 7 that are in communication. When growing into a mature shrimp in a state, the breeding tub 1 is formed such that the volume of the late breeding tub 55 becomes four times the volume of the initial breeding tub 5, and the breeding tub 1 is placed in the chambers 14a to 14e. The first growing tank 5 is divided into five parts, and the first growing tank 5 and the common growing tank 7 are connected to each other by the other four to form a later growing tank 55.
[0040]
Further, as described above, since the sand beds 8 are laid in each of the chambers 14a to 14e of the breeding tub 1, it is suitable for breeding shrimp and other fish and shellfish having habit of dive in the sand. Each of the chambers 14a to 14e of the breeding tub 1 is partitioned by a partition wall 9 whose upper end is located above the upper surface of the sand bed 8 and below the surface of the breeding water 2, and a partition plate is provided on the partition wall 9. By arranging 10, the partition 6 between the initial breeding tub 5 and the common breeding tub 7 is formed, so that the initial breeding tub 5 for growing the fish and shellfish in the initial state and the seafood in the intermediate state are separated. The common breeding tank 7 that grows can be completely divided in both the sand bed 8 and the breeding water 2 by the partitioning section 6 composed of the partition wall 9 and the partition plate 10, and the seafood that dives on the sand bed 8 Can be prevented from moving between them.
[0041]
Here, when the fish and shellfish 12 has a habit of dive into the sand bed 8 as described above, it is difficult to capture the fish and shellfish 12 when the fish and shellfish 12 grown in a shippable state are taken out of the breeding tub 1 and shipped. It is. Therefore, in the present invention, as described above, the catching net 11 whose opening is larger than the sand particle size and smaller than the fish and shellfish is laid below the sand bed 8. Then, as shown in FIG. 11 (a), when the end of the catching net 11 protruding above the side wall of the breeding tub 1 is pulled, the catching net 11 having a mesh size larger than the sand particle diameter passes through the sand bed 8. As shown in FIG. 11 (b), not only the seafood 12 swimming in the breeding water 2 of the breeding tank 1, but also the seafood 12 that has dived on the sand bed 8, as shown in FIG. It can be caught on top and can be caught and taken out without any escape.
[0042]
At this time, as shown in FIG. 12, a plurality of catching nets 11 are stacked so as to be stretched under the sand bed 8, and when the fish and shellfish 12 grown to be ready for shipment are taken out of the breeding tub 1 and shipped. By pulling up the catching net 11 one by one from the top to catch the fish and shellfish 12, every time the fish and shellfish 12 is taken out of the breeding tub 1 and shipped, the catching net 11 is placed under the sand bed 8. This eliminates the need to rebuild 11.
[0043]
【The invention's effect】
As described above, the fish and shellfish cultivation system according to claim 1 of the present invention comprises a breeding tank for breeding seafood provided with a sand bed at the bottom, breeding water purification means for purifying breeding water in the breeding tank, and breeding. In a fish and shellfish cultivation system having a circulating means for circulating water between a breeding tank and a breeding water purifying means, a foreign matter discharge port is provided at one end of the breeding tank, and at the other end opposite to the foreign matter discharge port. A water flow generating means for generating a water flow toward the foreign matter discharge port is provided, and after the water level on the sand bed is lowered, a water flow is generated by the water flow generating means, and the foreign matter on the sand bed is discharged to the foreign matter discharge port by the water flow. Therefore, the water level on the sand bed is low and foreign matter on the sand bed can be washed away with a strong current, and even if the foreign matter on the sand bed is a large solid foreign matter, it can be efficiently discharged from the foreign matter discharge port and cleaned. It is.
[0044]
According to a second aspect of the present invention, in the first aspect, a foreign matter discharge port is provided on the side wall of the breeding tub at a position slightly above the upper surface of the sand bed, and drainage for breeding water in the breeding tub at a position above the foreign matter discharge port is provided. Since the mouth is provided and the drain is connected to the circulation means, when washing away foreign matter on the sand bed with a water stream, the foreign matter flows into the foreign matter discharge port located slightly above the upper surface of the sand bed and rises above the foreign matter discharge port. It does not flow into the disposed drain port, and can prevent foreign substances from flowing into the circulation means from the drain port.
[0045]
According to a third aspect of the present invention, in accordance with the first or second aspect of the present invention, since a storage tank for storing foreign matter discharged to the foreign matter discharge port together with water is provided, the supernatant is bred after the foreign matter is settled in the storage water tank. Water can be returned to the system and reused for aquaculture, and the amount of breeding water to be replenished to the system can be reduced.
[0046]
The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein a plurality of partition walls whose upper ends are located above the upper surface of the sand bed and below the water surface of the breeding water are provided in the breeding tank. Since the foreign matter discharge port and the water flow generating means are provided facing each other between the partition walls, the water flow from the water flow generating means is not guided by the partition walls on both sides and spreads sideways, and the The foreign matter can be efficiently washed out and discharged to the foreign matter discharge port.
[0047]
According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a pair of breeding tubs are provided, and each breeding tub is connected by a circulating means, and breeding water in one breeding tub is supplied to the other breeding tub through the circulating means. To lower the water level on the sand bed of one of the breeding tanks, so that the water level on the sand bed of the breeding tank can be lowered by moving the breeding water in the system. It is not necessary to discharge breeding water out of the system when lowering the breeding water.
[0048]
According to a sixth aspect of the present invention, in the fifth aspect, the water flow generating means provided in each breeding tub is connected to the circulating means, and the breeding water in one breeding tub is sent to the other breeding tub through the circulating means. After lowering the water level on the sand bed of one of the breeding tanks and raising the water level of the other breeding tub, the water in the other breeding tub is supplied to the breeding tub through the circulation means by the difference in water level. Since the water flow is sent to the generation means and discharged from the water flow generation means to generate the water flow, the water flow generation means is utilized by lowering the water level on the sand bed of one of the breeding tanks by utilizing the difference in water level between the two breeding tanks. The breeding water can be discharged from the water to generate a water flow, and power and the like for generating the water flow become unnecessary.
[0049]
According to a seventh aspect of the present invention, in any one of the first to sixth aspects, a catching net having an eye larger than the grain size of the sand is stretched below the sand bed, and the catching net is placed above the sand bed. By raising, fish and shellfish are caught on the catching net, so not only seafood swimming in the breeding water in the breeding tank but also seafood lurking on the sand bed are captured on the catching net. And fish that can be caught without escape.
[0050]
According to the invention of claim 8, in claim 7, a plurality of catching nets are stacked and stretched under the sand bed, and the catching nets are pulled up one by one from above. It is possible to carry out the operation of catching fish and shellfish multiple times by pulling it up, eliminating the need to re-establish the catching net under the sand bed every time the fish and shellfish are taken out of the breeding tank and shipped. is there.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a breeding tub according to an example of an embodiment of the present invention, cut in a lateral direction.
FIG. 2 is a plan view showing an example of an embodiment of the present invention.
FIG. 3 is a perspective view of the same.
FIG. 4 is a cross-sectional view of the breeding tank, which is cut in a longitudinal direction.
5A and 5B show a net plate portion of the breeding tank, wherein FIG. 5A is a front view and FIG. 5B is a plan view.
FIGS. 6A and 6B are schematic cross-sectional views showing a state in which foreign matter in the breeding tank is cleaned.
FIG. 7 is a plan view showing the open / closed state of the on-off valve when cleaning foreign matter in the breeding tank.
FIG. 8 is a plan view showing the open / closed state of the on-off valve when cleaning foreign matter in the breeding tank.
FIG. 9 is a plan view showing the open / closed state of the on-off valve when cleaning foreign matter in the breeding tank.
FIG. 10 is a schematic plan view showing the breeding state of the same fish and shellfish as in the first embodiment.
FIG. 11 shows a state in which the same fish and shellfish are captured and taken out of the breeding tank, and (a) and (b) are cross-sectional views, respectively.
FIG. 12 is a cross-sectional view showing another example of a state in which the above fish and shellfish are captured and taken out of the breeding tank.
FIG. 13 is a schematic diagram showing a configuration of the culture system of the above.
[Explanation of symbols]
1 Breeding tank
2 Breeding water
3 Breeding water purification means
4 Circulation means
8 Sand floor
9 Partition wall
11 Net for capture
12 Seafood
13 Water flow generating means
29 drainage outlet
30 Foreign matter discharge port
33 storage tank

Claims

A breeding tank for raising fish and shells provided with a sand bed at the bottom, breeding water purification means for purifying breeding water in the breeding tank, and circulation means for circulating breeding water between the breeding tank and the breeding water purification means In a fish and shellfish cultivation system, a foreign matter discharge port is provided at one end of the breeding tank, and a water flow generating means for generating a water flow toward the foreign matter discharge port is provided at the other end opposite to the foreign matter discharge port, A seafood cultivation system, characterized in that a water flow is generated by a water flow generating means after the water level is lowered, and foreign matter on the sand bed is discharged to the foreign matter discharge port by the water flow.

At the side wall of the breeding tub, a foreign substance discharge port is provided at a position slightly above the upper surface of the sand bed, and at the position above the foreign substance discharge port, a drain port for discharging breeding water in the breeding tank is provided, and the drain port is connected to circulation means. The fish and shellfish cultivation system according to claim 1, wherein

The fish and shellfish cultivation system according to claim 1 or 2, further comprising a storage tank for storing foreign matter discharged to the foreign matter discharge port together with water.

A plurality of partition walls whose upper ends are above the upper surface of the sand bed and below the surface of the breeding water are provided in the breeding tank, and the foreign matter discharge port and the water flow generating means are provided between the adjacent partition walls so as to face each other. The fish and shellfish cultivation system according to any one of claims 1 to 3, characterized in that it comprises:

By providing a pair of breeding tanks and connecting each breeding tank by circulation means, by sending the breeding water in one breeding tank to the other breeding tank through the circulation means, the water level on the sand bed of one breeding tank is lowered. The fish and shellfish cultivation system according to any one of claims 1 to 4, characterized in that it comprises:

By connecting the water flow generating means provided in each breeding tub to the circulating means, and sending the breeding water in one breeding tub to the other breeding tub through the circulating means, while lowering the water level on the sand bed of one breeding tub After raising the water level in the other breeding tank, the difference in the water level causes the breeding water in the other breeding tank to be sent to the water flow generating means provided in one of the breeding tanks through the circulating means, and to be discharged from the water flow generating means. The fish and shellfish cultivation system according to claim 5, wherein the fish and shellfish are produced.

Under the sand bed, a catching net with eyes larger than the grain size of the sand is stretched, and the catching net is pulled up above the sand bed so that fish and shellfish are caught on the catching net. The fish and shellfish cultivation system according to any one of claims 1 to 6, wherein

8. The fish and shellfish cultivation system according to claim 7, wherein a plurality of catching nets are stacked and stretched below the sand bed, and the catching nets are pulled up one by one from above.