JPH0217135B2 - - Google Patents
Info
- Publication number
- JPH0217135B2 JPH0217135B2 JP59039778A JP3977884A JPH0217135B2 JP H0217135 B2 JPH0217135 B2 JP H0217135B2 JP 59039778 A JP59039778 A JP 59039778A JP 3977884 A JP3977884 A JP 3977884A JP H0217135 B2 JPH0217135 B2 JP H0217135B2
- Authority
- JP
- Japan
- Prior art keywords
- nutrient solution
- section
- heat
- temperature
- tank
- 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 - Lifetime
Links
- 235000015097 nutrients Nutrition 0.000 claims description 220
- 230000001954 sterilising effect Effects 0.000 claims description 55
- 238000004659 sterilization and disinfection Methods 0.000 claims description 48
- 238000001816 cooling Methods 0.000 claims description 40
- 238000010521 absorption reaction Methods 0.000 claims description 39
- 238000010438 heat treatment Methods 0.000 claims description 38
- 230000005855 radiation Effects 0.000 claims description 35
- 239000003507 refrigerant Substances 0.000 claims description 32
- 230000017525 heat dissipation Effects 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 6
- 230000006835 compression Effects 0.000 description 3
- 238000007906 compression Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 230000005541 medical transmission Effects 0.000 description 1
- 238000009335 monocropping Methods 0.000 description 1
- 244000052769 pathogen Species 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Classifications
-
- Y02P60/216—
Landscapes
- Hydroponics (AREA)
- Dairy Products (AREA)
- Apparatus For Disinfection Or Sterilisation (AREA)
Description
本発明は作物の養液栽培に用いられる養液栽培
装置に係り、特に養液栽培の病害対策に対処し、
かつ水温を最適温度に維持することが可能な養液
栽培装置に関する。
The present invention relates to a hydroponic device used for hydroponic cultivation of crops, and particularly deals with disease control in hydroponic cultivation,
The present invention also relates to a hydroponic cultivation device capable of maintaining water temperature at an optimum temperature.
土壌を用いないで作物の栽培を行う養液栽培の
長所として(1)省力化及び自動化が容易である、(2)
連作障害がない、(3)土壌栽培に比べ収穫量が多
い、など数多くの長所があるが、反面、養液を循
環させているため、一度養液中に病原菌が混入し
た場合、病害の伝染速度が大きく被害が大きいと
いう欠点を有している。従つて、養液栽培におい
て養液の殺菌は最も重要な問題の１つである。
そこで、従来この種の殺菌装置を有する養液栽
培装置として第１図Ａに示すものがあつた。
図において１は作物、２は栽培槽、３は養液タ
ンク、４は養液、５は上記栽培槽２と養液タンク
を連結する養液循環路、６はポンプ、７は養液加
温殺菌部、８は養液冷却部である。
次に動作について説明する。養液４が養液循環
ポンプ６によつて養液タンク３と栽培槽２の間を
循環路５を通つて連続的、あるいは間欠的に循環
する。その際、養液４がポンプ６によつて養液タ
ンク３からくみ上げられ、その後養液加温殺菌部
７によつて殺菌するに十分な温度まで加温され、
その後、養液冷却部８により周囲に放熱し、作物
栽培に適した温度まで冷却され栽培槽２に至る。
以後養液４は上記循環を繰り返えす。しかしなが
ら上記従来の養液栽培装置は養液の加温に要する
エネルギが大きく、かつ加温殺菌後に養液を冷却
しても、養液の温度を周囲温度以下に下げられな
いという欠点がある。
そこで、上記従来装置を改良したものが提案さ
れており、以下にその改良装置を第１図Ｂに基づ
いて説明する。図において１は作物、２は栽培
槽、３は養液タンク、４は養液、５は養液循環
路、６はポンプ、７は養液加温殺菌部、８は養液
冷却部、９は養液放熱部、１０は放熱用フアン、
１１は機械圧縮式のヒートポンプ、１２は上記ヒ
ートポンプの熱交換部である放熱部、１３は上記
ヒートポンプの熱交換部である吸熱部、１４は冷
媒蒸気圧縮機、１５は減圧弁、１６は冷媒循環路
である。
次に動作を説明する。
養液４は養液タンク３からポンプ６によつて吸
い上げられ、養液加温殺菌部７でヒートポンプ１
１の放熱部１２と熱交換することにより殺菌する
に十分な温度まで加温され、次いで養液放熱部９
で一次冷却され、さらに養液冷却部８にて上記ヒ
ートポンプ１１の吸熱部１３との熱交換により作
物栽培に適した温度まで二次冷却され、栽培槽２
に入り、再び養液タンク３に戻る。
以後上記養液循環が繰り返される。
従来装置を改良した養液栽培装置は以上のよう
に構成されているので、養液の加温殺菌と二次冷
却が同一のヒートポンプにて省エネルギ的に行
え、また、放熱部での放熱量を制御することによ
り、養液温度を作物栽培の適温に維持でき、この
温度を周囲温度以下にすることも可能であるとい
う長所を有しているが、この従来装置は、養液を
加温殺菌しながら養液温度を適正に保つことを主
目的としているため、単に養液の温度を栽培に最
適な温度に保ちたい場合も加温殺菌しなければな
らず不経済になるという欠点があつた。
Advantages of hydroponic cultivation, which cultivates crops without using soil, are (1) easy labor-saving and automation; (2)
It has many advantages, such as no continuous cropping problems and (3) higher yields than soil cultivation, but on the other hand, because the nutrient solution is circulated, once pathogens are mixed into the nutrient solution, there is a risk of disease transmission. It has the disadvantage of high speed and great damage. Therefore, sterilization of the nutrient solution is one of the most important issues in hydroponic cultivation. Therefore, as a conventional hydroponic cultivation apparatus having this type of sterilization apparatus, there was one shown in FIG. 1A. In the figure, 1 is a crop, 2 is a cultivation tank, 3 is a nutrient tank, 4 is a nutrient solution, 5 is a nutrient circulation path connecting the cultivation tank 2 and the nutrient tank, 6 is a pump, and 7 is a nutrient solution heating The sterilization section and 8 are the nutrient solution cooling section. Next, the operation will be explained. The nutrient solution 4 is continuously or intermittently circulated between the nutrient solution tank 3 and the cultivation tank 2 through the circulation path 5 by the nutrient solution circulation pump 6. At that time, the nutrient solution 4 is pumped up from the nutrient solution tank 3 by the pump 6, and then heated to a temperature sufficient for sterilization by the nutrient solution heating and sterilization section 7.
Thereafter, the nutrient solution cooling section 8 radiates heat to the surroundings, and the solution is cooled down to a temperature suitable for crop cultivation and reaches the cultivation tank 2.
Thereafter, the nutrient solution 4 repeats the above circulation. However, the above-mentioned conventional hydroponic cultivation apparatus has the disadvantage that a large amount of energy is required to heat the nutrient solution, and the temperature of the nutrient solution cannot be lowered to below the ambient temperature even if the nutrient solution is cooled after heating and sterilization. Therefore, an improved version of the above conventional device has been proposed, and the improved device will be explained below with reference to FIG. 1B. In the figure, 1 is a crop, 2 is a cultivation tank, 3 is a nutrient solution tank, 4 is a nutrient solution, 5 is a nutrient solution circulation path, 6 is a pump, 7 is a nutrient solution heating sterilization section, 8 is a nutrient solution cooling section, 9 is a nutrient solution heat dissipation part, 10 is a heat dissipation fan,
11 is a mechanical compression type heat pump, 12 is a heat radiation part which is a heat exchange part of the heat pump, 13 is a heat absorption part which is a heat exchange part of the heat pump, 14 is a refrigerant vapor compressor, 15 is a pressure reducing valve, and 16 is a refrigerant circulation It is a road. Next, the operation will be explained. The nutrient solution 4 is sucked up from the nutrient solution tank 3 by the pump 6, and is transferred to the heat pump 1 in the nutrient solution heating and sterilization section 7.
It is heated to a temperature sufficient for sterilization by exchanging heat with the heat radiating part 12 of 1, and then the nutrient solution heat radiating part 9
The nutrient liquid cooling section 8 cools the nutrient liquid to a temperature suitable for crop cultivation by heat exchange with the heat absorption section 13 of the heat pump 11, and then cools the cultivation tank 2.
and return to the nutrient solution tank 3 again. Thereafter, the above nutrient solution circulation is repeated. The hydroponic cultivation device, which is an improved version of the conventional device, is configured as described above, so that the heating sterilization and secondary cooling of the nutrient solution can be performed using the same heat pump in an energy-saving manner, and the amount of heat radiated by the heat radiating section is reduced. By controlling the temperature of the nutrient solution, it is possible to maintain the temperature of the nutrient solution at an appropriate temperature for crop cultivation, and it has the advantage that this temperature can even be lowered to below ambient temperature. Since the main purpose is to maintain the temperature of the nutrient solution at an appropriate level while sterilizing it, it has the disadvantage that even if you simply want to maintain the temperature of the nutrient solution at the optimal temperature for cultivation, you have to heat and sterilize it, which becomes uneconomical. Ta.
この発明は上記のような欠点を除去するために
なされたもので、養液の加温殺菌をヒートポンプ
によつて省エネルギ的に行え、かつ殺菌をしない
通常時には、加温殺菌と冷却に用いるヒートポン
プと同一ヒートポンプによつて養液の温度を栽培
に最適な温度に調節できるような養液栽培装置を
提供することを目的としている。
This invention was made in order to eliminate the above-mentioned drawbacks, and it is possible to use a heat pump to heat and sterilize a nutrient solution in an energy-saving manner, and when sterilization is not normally performed, the heat pump used for heating and sterilization and cooling can be used. The purpose of the present invention is to provide a hydroponic cultivation device that can adjust the temperature of the nutrient solution to the optimum temperature for cultivation using the same heat pump as the one described above.
以下この発明の一実施例を第２図に基づいて説
明する。図中、第１図Ｂと同一符号のものは同様
の構成要素を示す。第２図において、１７は養液
温度調節部、１８は三方弁２０と四方弁２１との
切換によつてヒートポンプ１１の放熱源あるいは
吸熱源として機能し、上記養液温度調節部１７と
熱交換する副熱源部の１つである養液温度調節用
副熱源部２３はこの養液温度調節用副熱源部１８
がなす機能とは逆の機能をなす別の副熱源部、２
０は三方弁であり、この三方弁２０の切換によ
り、上記ヒートポンプ１１の冷媒回路は減圧弁１
５ａを有する養液殺菌時冷媒回路（主冷媒回路）
１６ａ、あるいは減圧弁１５ｂを有する温度調節
時冷媒回路（副冷媒回路）１６ｂに切換られる。
２１は四方弁であり、この四方弁２１により温度
調節運転時に温度調節時冷媒回路１５ｂ内を流れ
る冷媒の方向を切換えることにより上記養液温度
調節熱源部１８をヒートポンプの吸熱源あるいは
放熱源に設定できる。
次に動作を説明する。
まず養液４の循環について説明する。養液４は
養液タンク３よりポンプ６によつて吸上げられ、
養液循環路５内に設定された養液加温殺菌部７、
養液放熱部９、養液冷却部８、養液温度調節部１
７を順次通過し、栽培槽２に至り、その後養液タ
ンク３に戻る。
次いで、本発明装置の養液加温殺菌時の動作に
ついて説明する。
養液加温殺菌時には、ヒートポンプ１１の三方
弁２０の切換により、ヒートポンプ１１の冷媒循
環路は主冷媒回路１６ａに選択される。このと
き、ヒートポンプ１１は主放熱部１２で放熱し、
主吸熱部１３で吸熱する。その際養液４は、養液
加温殺菌部７で殺菌するに十分な温度までヒート
ポンプ１１の主放熱部１２との熱交換により加温
され、次いで、養液放熱部９で放熱用フアン１０
による強制空冷にて一次冷却され、さらに養液冷
却部８にて、ヒートポンプ１１の主吸熱部１３と
の熱交換により栽培に最適な温度まで冷却され
る。このとき養液４の温度の調節は、養液放熱部
９での放熱量を例えば放熱用フアン１０の風量の
制御により調節することにより可能である。養液
冷却部８を出た養液４はその後養液温度調節部１
７を経て栽培槽２へ至るが、上記養液温度調節部
１７では加温も冷却もされない。この際養液冷却
部８から直接栽培槽２へ至る別の養液循環路（図
示せず）を設け、三方弁２０と同時に作動する弁
（図示せず）によつて上記別養液循環路を通して
養液冷却部８から栽培槽２へ直接養液４を導いて
も良いことは言うまでもない。
次いで本装置の養液温度調節時の動作について
説明する。
上述した通り、本発明の装置では、養液加温殺
菌時にも養液４の温度を調節する機能を有してい
るが、以下に養液４を加温殺菌せずに単に温度調
節のみを行う場合の動作について説明する。
養液温度調節時には、三方弁２０の切換により
ヒートポンプ１１の冷媒循環路は副冷媒回路１６
ｂに選択される。
さらに、養液４を温度調節するために養液４を
加温する場合には養液温度調節用副熱源部１８を
ヒートポンプ１１の放熱源とし、別の副熱源部２
３を吸熱源とするようにして機能させる。逆に養
液４を冷却する場合には、養液温度調節用副熱源
部１８をヒートポンプ１１の吸熱源とし、別の副
熱源部２３を放熱源とするように四方弁２１を切
換える。
第２図は養液温度調節用副熱源部１８をヒート
ポンプ１１の吸熱源とした場合の冷媒流路を形成
する四方弁２１を示し、第３図は養液温度調節用
副熱源部１８をヒートポンプ１１の放熱源とした
場合の部分的な冷媒流路を形成する四方弁２１を
示す。
養液４は養液加温殺菌部７、養液放熱部９、養
液冷却部８を通過する際には加温も冷却もされ
ず、養液温度調節部１７で、作物１の栽培に最適
な温度に加温あるいは冷却されるが、この場合も
別の養液回路（図示せず）を設け、養液４をポン
プ６から直接養液温度調節部１７に導くようにし
ても良いことは言うまでもない。
なお、上記実施例では養液加温殺菌部７、養液
冷却部８とは別に養液温度調節部１７を設置した
場合を示したが、養液温度調節部１７を後記第４
図に示すように、養液加温殺菌部７あるいは養液
冷却部８と共通化するような構成も可能である。
第４図に本発明の他の実施態様の構成図を示
す。
図中、２２ａ，２２ｂは三方弁、２３ａ，２３
ｂはそれぞれヒートポンプ１１の吸熱源および放
熱源として機能する副吸熱部と副放熱部であり、
この２つがこの実施態様の場合の副熱源部であ
る。２４ａ，２４ｂはそれぞれヒートポンプ１１
の副吸熱部２３ａ、副放熱部２３ｂを通る副冷媒
循環路である。
養液の加温殺菌を行う場合には、ヒートポンプ
１１の冷媒サイクルは、圧縮機１４から主放熱部
１２、減圧弁１５、主吸熱部１３を経由して圧縮
機１４の順路となり、本発明の装置は、第１図Ｂ
に示した従来例と同様の動作を行う。
さて、非殺菌時すなわち養液の温度調節のみを
行う場合の本装置の動作を説明する。養液を加温
する場合には、三方弁２２ａを切換えることによ
りヒートポンプ１１の冷媒サイクルは、圧縮機１
４から主放熱部１２、減圧弁１５、副吸熱部２３
ａを経て圧縮機１４の順路となり、また、放熱用
フアン１０は停止させる。これにより養液４は養
液加温殺菌部７において、ヒートポンプ１１の主
放熱部１２との熱交換により加温されるが、養液
放熱部９、養液冷却部８を通過する際には加温・
冷却されずに栽培槽２に至る。よつて、この場合
には養液加熱殺菌部７で養液の温度調節を行うこ
とになる。
養液４を冷却する場合には、前記と同様にし
て、三方弁２２ｂを切換えることにより、養液４
は養液加温殺菌部７、養液放熱部９では加温・冷
却されずに、養液冷却部８でのみ冷却される。よ
つて、この場合には養液冷却部８で養液の温度調
節を行うことになる。なお、加温や冷却の程度
は、養液循環量や、ヒートポンプ１１の能力を調
節することにより制御可能である。
さらに他の実施例を第５図に示す。
この図に示した装置では、第４図に示した装置
に比べ副熱源部が符号２３を付した１つのみの構
成となつており、そのかわり四方弁２１を備えて
いる。
この実施例において、養液の加温殺菌を行う場
合、ヒートポンプ１１の冷媒回路（主冷媒回路）
は、圧縮機１４から主放熱部１２、減圧弁１５、
主吸熱部１３を経由して圧縮機１４の順路とな
り、この場合には、主放熱部１２と主吸熱部１３
がヒートポンプの放熱源、吸熱源として機能す
る。
次に非殺菌時の動作について説明する。非殺菌
時には、三方弁２２の切換えによりヒートポンプ
１１の冷媒回路は主放熱部１２を通過せず副熱源
部２３を通るようになる。つまり副冷媒回路は圧
縮機１４、副熱源部２３、減圧弁１５、主吸熱部
１３の構成となる。
さて、非殺菌時、養液４の温度を栽培に最適な
温度に維持するため、養液４を冷却する場合に
は、四方弁２１を第５図に示すように切換える。
このとき、主吸熱部１３はヒートポンプ１１の吸
熱源として、副熱源部２３の放熱源として機能す
る。
養液４は養液加温殺菌部７および養液放熱部９
では加熱も冷却もされず、養液冷却部８におい
て、ヒートポンプ１１の主吸熱部１３と熱交換す
ることにより冷却される。
逆に、非殺菌時、養液４を加熱する場合には、
四方弁２１を第５図とは逆に切換える。このとき
ヒートポンプ１１の副冷媒回路において、主吸熱
部１３は放熱源として、副熱源部２３は吸熱源と
して機能することになり、従つて養液４は養液冷
却部８で栽培に最適な温度まで加熱される。
さて以上の実施例はヒートポンプとして一段式
のものを用いているが、ヒートポンプ１１を多段
式にすることにより、ヒートポンプ１１の成積係
数をより大きくできる。第６図に示した他の実施
例はヒートポンプ１１として二段式の機械圧縮式
ヒートポンプを用いた場合のものである。この場
合にも第５図の場合と同様に養液冷却部８にて養
液の温度調節を行う。
図において、１６ａは低温段の冷媒循環路、１
６ｂは高温段の冷媒循環路、２５ａは低温段の放
熱部、２５ｂは高温段の吸熱部、１４ａ，１４ｂ
は夫々低温段、高温段用圧縮機、２３は低温段の
副熱交換部である。
次に上記第６図の実施例動作を説明する。ま
ず、養液殺菌時にはヒートポンプは低温段、高温
段とも動作する。四方弁２１は、低温段の主吸熱
部１３が吸熱源として働くよう図に示したように
なつている。また、三方弁２２は冷媒が低温段の
放熱部２５ａを通るように切換えられる。
養液加温殺菌部７はヒートポンプ１１の高温段
の主放熱部１２と熱交換し、ここで養液４は殺菌
するに十分な温度まで加温される。その後、養液
放熱部９にて、栽培槽２の入口での養液温度が栽
培に適当な温度になるように一次冷却され、さら
に養液冷却部８にて二次冷却される。
非殺菌時には養液放熱部９の放熱用フアン１０
を停止し、かつヒートポンプ１１の高温段は動作
させず、低温段のみにて養液の温度調節を行う。
また三方弁２２は低温段の副熱交換部２３に冷媒
が流れるように切換えられる。ここで、養液４を
加温する場合には四方弁２１を切換えて、ヒート
ポンプ１１の低温段の主吸熱部１３を放熱源とし
て機能させ副熱交換部２３を吸熱源として機能さ
せる。また養液を冷却する場合には逆に、ヒート
ポンプ低温段の主吸熱部１３が吸熱源に、副熱交
換部２３が放熱源になるように四方弁２１を切換
える。このように二段式のヒートポンプを用いる
場合には、低温段のみを動作させて温度調節でき
るので、ヒートポンプ１１の高い成積係数が期待
でき、より省エネルギ的となる。
さて上記実施例では、養液タンク３から栽培槽
２に至る養液循環路５にて、養液４をヒートポン
プ１１の放熱源あるいは吸熱源と熱交換させるこ
とにより殺菌や温度調節を行つたが、これらは養
液循環路５内のどの位置に放置しても良く、また
第７図に示した構成図のように、養液タンク３か
ら該養液タンクに戻る別の養液循環路５ａの途中
において、養液の殺菌及び温度調節を行つてもよ
い。図中６ａは上記別養液循環路５ａ用の養液循
環ポンプである。
また上記実施例では養液放熱部９における養液
の冷却または、ヒートポンプ１１の副熱交換部１
３，２３，２３ａ，２３ｂにおける熱交換をフア
ンの強制対流による空冷により行つているが、自
然空冷でも、また冷却水による水冷によつても良
いことは言うまでもない。
さらに上記実施例ではヒートポンプとして、蒸
気機械圧縮式のものを用いているが、吸収式ヒー
トポンプなど他原理のヒートポンプを用いても良
いことは言うまでもない。
さて、本発明は上記のように殺菌運転時は養液
放熱部での放熱量を制御することにより、また非
殺菌時には養液循環量やヒートポンプ能力の調節
や、ヒートポンプのON−OFF制御などによつて
養液加熱量あるいは養液冷却量を制御することに
より、養液の温度を作物栽培に最適な温度に維持
することが可能であるが、より正確に養液温度を
最適温度に制御するためには、養液の温度を検知
し、それによつてポンプ、圧縮機、減圧弁、フア
ンなど種々の機器の制御を行う方が望ましい。第
７図において示した２６ａ，２６ｂはこの目的の
ために設置された温度検出器である。
また養液殺菌時の養液加温殺菌部７の温度も検
知し、養液が殺菌に十分な温度まで加温されるよ
うに、ポンプ、圧縮機、減圧弁などの制御を行う
ことも可能である。第７図において示した２７は
この目的のために設置された温度検出器である。
さらに栽培部での養液の温度と、殺菌部での養
液を両方検知し、それらを適正に保つように種々
の機器を制御することも可能である。ただし、本
発明は上述した種々の制御対象機器や制御方法を
限定するものではない。
An embodiment of the present invention will be described below with reference to FIG. In the figure, the same reference numerals as in FIG. 1B indicate the same components. In FIG. 2, 17 is a nutrient solution temperature control section, and 18 is a heat radiating source or a heat absorption source for the heat pump 11 by switching between a three-way valve 20 and a four-way valve 21, and exchanges heat with the nutrient solution temperature control section 17. The nutrient solution temperature adjustment auxiliary heat source section 23, which is one of the nutrient solution temperature adjustment auxiliary heat source sections, is one of the nutrient solution temperature adjustment auxiliary heat source sections 18.
Another auxiliary heat source that performs the opposite function to that performed by 2.
0 is a three-way valve, and by switching this three-way valve 20, the refrigerant circuit of the heat pump 11 is connected to the pressure reducing valve 1.
Refrigerant circuit during sterilization with nutrient solution (main refrigerant circuit) with 5a
16a, or a temperature adjustment refrigerant circuit (sub-refrigerant circuit) 16b having a pressure reducing valve 15b.
21 is a four-way valve, and this four-way valve 21 switches the direction of the refrigerant flowing in the refrigerant circuit 15b during temperature adjustment during temperature adjustment operation, thereby setting the nutrient solution temperature adjustment heat source section 18 as a heat absorption source or heat radiation source of the heat pump. can. Next, the operation will be explained. First, the circulation of the nutrient solution 4 will be explained. The nutrient solution 4 is sucked up from the nutrient solution tank 3 by the pump 6,
a nutrient solution heating sterilization section 7 set within the nutrient solution circulation path 5;
Nutrient solution heat radiation section 9, nutrient solution cooling section 8, nutrient solution temperature adjustment section 1
7 sequentially, reaches the cultivation tank 2, and then returns to the nutrient solution tank 3. Next, the operation of the apparatus of the present invention during sterilization by heating a nutrient solution will be explained. During heating and sterilization of the nutrient solution, the three-way valve 20 of the heat pump 11 is switched to select the main refrigerant circuit 16a as the refrigerant circulation path of the heat pump 11. At this time, the heat pump 11 radiates heat through the main heat radiating section 12,
The main heat absorption part 13 absorbs heat. At this time, the nutrient solution 4 is heated by heat exchange with the main heat radiating section 12 of the heat pump 11 to a temperature sufficient to sterilize it in the nutrient solution heating sterilization section 7, and then in the nutrient solution heat radiating section 9 using a heat radiating fan 10.
It is primarily cooled by forced air cooling, and further cooled to the optimum temperature for cultivation in the nutrient solution cooling section 8 by heat exchange with the main heat absorption section 13 of the heat pump 11. At this time, the temperature of the nutrient solution 4 can be adjusted by adjusting the amount of heat radiated by the nutrient solution heat radiating section 9, for example, by controlling the air volume of the heat radiating fan 10. The nutrient solution 4 that has exited the nutrient solution cooling section 8 is then transferred to the nutrient solution temperature control section 1.
7 and reaches the cultivation tank 2, but the nutrient solution temperature control section 17 neither heats nor cools it. At this time, a separate nutrient solution circulation path (not shown) is provided that leads directly from the nutrient solution cooling section 8 to the cultivation tank 2, and the separate nutrient solution circulation path is controlled by a valve (not shown) that operates simultaneously with the three-way valve 20. It goes without saying that the nutrient solution 4 may be directly guided from the nutrient solution cooling section 8 to the cultivation tank 2 through the nutrient solution cooling section 8. Next, the operation of this device when adjusting the temperature of the nutrient solution will be explained. As mentioned above, the device of the present invention has the function of adjusting the temperature of the nutrient solution 4 even during heating and sterilization of the nutrient solution. The operation when doing this will be explained. When adjusting the temperature of the nutrient solution, the refrigerant circulation path of the heat pump 11 is switched to the auxiliary refrigerant circuit 16 by switching the three-way valve 20.
b. Furthermore, when heating the nutrient solution 4 to adjust the temperature of the nutrient solution 4, the auxiliary heat source section 18 for nutrient solution temperature adjustment is used as the heat radiation source of the heat pump 11, and another auxiliary heat source section 2 is used.
3 to function as a heat absorption source. Conversely, when cooling the nutrient solution 4, the four-way valve 21 is switched so that the nutrient solution temperature adjustment sub-heat source section 18 is used as the heat absorption source of the heat pump 11, and another sub-heat source section 23 is used as the heat radiation source. FIG. 2 shows a four-way valve 21 that forms a refrigerant flow path when the auxiliary heat source section 18 for adjusting the temperature of the nutrient solution is used as the heat absorption source of the heat pump 11, and FIG. 11 shows a four-way valve 21 forming a partial refrigerant flow path when used as a heat radiation source. The nutrient solution 4 is neither heated nor cooled when passing through the nutrient solution heating and sterilization section 7 , the nutrient solution heat radiation section 9 , and the nutrient solution cooling section 8 . Although the nutrient solution 4 is heated or cooled to an optimal temperature, in this case as well, another nutrient solution circuit (not shown) may be provided to guide the nutrient solution 4 directly from the pump 6 to the nutrient solution temperature control section 17. Needless to say. In the above embodiment, the nutrient solution temperature adjustment section 17 is installed separately from the nutrient solution heating sterilization section 7 and the nutrient solution cooling section 8, but the nutrient solution temperature adjustment section 17 is installed in the fourth section described later.
As shown in the figure, a configuration in which the nutrient solution heating sterilization section 7 or the nutrient solution cooling section 8 is used in common is also possible. FIG. 4 shows a configuration diagram of another embodiment of the present invention. In the figure, 22a, 22b are three-way valves, 23a, 23
b are a sub-heat absorption part and a sub-heat radiation part which function as a heat absorption source and a heat radiation source of the heat pump 11, respectively;
These two are the auxiliary heat sources in this embodiment. 24a and 24b are heat pumps 11, respectively.
This is a sub-refrigerant circulation path passing through the sub-heat absorption section 23a and the sub-heat radiation section 23b. When sterilizing the nutrient solution by heating, the refrigerant cycle of the heat pump 11 is a route from the compressor 14 to the compressor 14 via the main heat radiation section 12, the pressure reducing valve 15, and the main heat absorption section 13. The device is shown in Figure 1B.
The operation is similar to that of the conventional example shown in . Now, the operation of this apparatus when not sterilizing, that is, when only controlling the temperature of the nutrient solution will be explained. When heating the nutrient solution, the refrigerant cycle of the heat pump 11 is switched to the compressor 1 by switching the three-way valve 22a.
4 to main heat dissipation section 12, pressure reducing valve 15, sub heat absorption section 23
The route for the compressor 14 is reached via point a, and the heat dissipation fan 10 is stopped. As a result, the nutrient solution 4 is heated in the nutrient solution heating sterilization section 7 by heat exchange with the main heat radiating section 12 of the heat pump 11, but when passing through the nutrient solution heat radiating section 9 and the nutrient solution cooling section 8, Warming·
It reaches the cultivation tank 2 without being cooled. Therefore, in this case, the temperature of the nutrient solution is adjusted in the nutrient solution heating sterilization section 7. When cooling the nutrient solution 4, the nutrient solution 4 is cooled by switching the three-way valve 22b in the same manner as described above.
is not heated or cooled in the nutrient solution heating sterilization section 7 or the nutrient solution heat radiation section 9, but is cooled only in the nutrient solution cooling section 8. Therefore, in this case, the temperature of the nutrient solution will be adjusted in the nutrient solution cooling section 8. Note that the degree of heating and cooling can be controlled by adjusting the amount of nutrient solution circulation and the capacity of the heat pump 11. Still another embodiment is shown in FIG. In the apparatus shown in this figure, compared to the apparatus shown in FIG. 4, there is only one auxiliary heat source section designated by the reference numeral 23, and a four-way valve 21 is provided instead. In this embodiment, when heating and sterilizing the nutrient solution, the refrigerant circuit (main refrigerant circuit) of the heat pump 11
is from the compressor 14 to the main heat radiation section 12, the pressure reducing valve 15,
The route of the compressor 14 passes through the main heat absorption part 13, and in this case, the main heat radiation part 12 and the main heat absorption part 13
functions as a heat radiation source and heat absorption source for the heat pump. Next, the operation during non-sterilization will be explained. During non-sterilization, the three-way valve 22 is switched so that the refrigerant circuit of the heat pump 11 does not pass through the main heat radiating section 12 but passes through the auxiliary heat source section 23. In other words, the auxiliary refrigerant circuit includes the compressor 14 , the auxiliary heat source section 23 , the pressure reducing valve 15 , and the main heat absorption section 13 . Now, when cooling the nutrient solution 4 in order to maintain the temperature of the nutrient solution 4 at the optimum temperature for cultivation when not sterilized, the four-way valve 21 is switched as shown in FIG.
At this time, the main heat absorption section 13 functions as a heat absorption source for the heat pump 11 and as a heat radiation source for the auxiliary heat source section 23. The nutrient solution 4 is supplied to a nutrient solution heating sterilization section 7 and a nutrient solution heat radiation section 9
The nutrient solution is neither heated nor cooled, but is cooled by exchanging heat with the main heat absorption section 13 of the heat pump 11 in the nutrient solution cooling section 8 . On the other hand, when heating the nutrient solution 4 without sterilization,
The four-way valve 21 is switched in the opposite direction to that shown in FIG. At this time, in the auxiliary refrigerant circuit of the heat pump 11, the main heat absorption section 13 functions as a heat radiation source, and the auxiliary heat source section 23 functions as a heat absorption source. Therefore, the nutrient solution 4 is heated to the optimum temperature for cultivation in the nutrient solution cooling section 8. heated up to. Now, in the above embodiments, a single-stage type heat pump is used, but by making the heat pump 11 a multi-stage type, the growth coefficient of the heat pump 11 can be made larger. Another embodiment shown in FIG. 6 uses a two-stage mechanical compression heat pump as the heat pump 11. In this case as well, the temperature of the nutrient solution is adjusted in the nutrient solution cooling section 8 as in the case of FIG. In the figure, 16a is the refrigerant circulation path of the low temperature stage;
6b is the refrigerant circulation path of the high temperature stage, 25a is the heat radiation part of the low temperature stage, 25b is the heat absorption part of the high temperature stage, 14a, 14b
are compressors for the low temperature stage and high temperature stage, respectively, and 23 is an auxiliary heat exchange section for the low temperature stage. Next, the operation of the embodiment shown in FIG. 6 will be explained. First, during nutrient solution sterilization, the heat pump operates in both the low-temperature stage and the high-temperature stage. The four-way valve 21 is configured as shown in the figure so that the main heat absorption section 13 of the low temperature stage acts as a heat absorption source. Moreover, the three-way valve 22 is switched so that the refrigerant passes through the heat radiation section 25a of the low temperature stage. The nutrient solution heating sterilization section 7 exchanges heat with the main heat radiation section 12 of the high temperature stage of the heat pump 11, and the nutrient solution 4 is heated here to a temperature sufficient for sterilization. Thereafter, in the nutrient solution heat dissipation section 9, the nutrient solution is first cooled so that the temperature of the nutrient solution at the entrance of the cultivation tank 2 becomes a temperature suitable for cultivation, and further cooled secondarily in the nutrient solution cooling section 8. When not sterilizing, the heat radiation fan 10 of the nutrient solution heat radiation section 9
and the high temperature stage of the heat pump 11 is not operated, and the temperature of the nutrient solution is adjusted only by the low temperature stage.
Moreover, the three-way valve 22 is switched so that the refrigerant flows into the sub-heat exchange section 23 of the low temperature stage. Here, when heating the nutrient solution 4, the four-way valve 21 is switched so that the main heat absorption section 13 of the low temperature stage of the heat pump 11 functions as a heat radiation source, and the secondary heat exchange section 23 functions as a heat absorption source. When cooling the nutrient solution, conversely, the four-way valve 21 is switched so that the main heat absorption section 13 of the heat pump low temperature stage becomes the heat absorption source and the secondary heat exchange section 23 becomes the heat radiation source. When a two-stage heat pump is used in this manner, the temperature can be adjusted by operating only the low-temperature stage, so a high growth coefficient of the heat pump 11 can be expected, resulting in greater energy savings. In the above embodiment, the nutrient solution 4 is sterilized and the temperature is adjusted by exchanging heat with the heat radiation source or heat absorption source of the heat pump 11 in the nutrient solution circulation path 5 from the nutrient solution tank 3 to the cultivation tank 2. , these may be left at any position within the nutrient solution circulation path 5, and as shown in the configuration diagram shown in FIG. 7, another nutrient solution circulation path 5a returning from the nutrient solution tank 3 to the nutrient solution tank During the process, the nutrient solution may be sterilized and its temperature adjusted. In the figure, 6a is a nutrient solution circulation pump for the separate nutrient solution circulation path 5a. In addition, in the above embodiment, cooling of the nutrient solution in the nutrient solution heat radiation section 9 or cooling of the nutrient solution in the nutrient solution heat radiating section 9 or
Although heat exchange in 3, 23, 23a, and 23b is performed by air cooling using forced convection from a fan, it goes without saying that natural air cooling or water cooling using cooling water may also be used. Furthermore, although a steam mechanical compression type heat pump is used as the heat pump in the above embodiment, it goes without saying that a heat pump based on another principle such as an absorption type heat pump may be used. As described above, the present invention controls the amount of heat radiated by the nutrient solution heat radiating section during sterilization operation, and also controls the nutrient solution circulation amount, heat pump capacity, heat pump ON/OFF control, etc. during non-sterilization operation. Therefore, it is possible to maintain the temperature of the nutrient solution at the optimal temperature for crop cultivation by controlling the amount of heating or cooling of the nutrient solution, but it is possible to more accurately control the temperature of the nutrient solution to the optimal temperature. For this purpose, it is desirable to detect the temperature of the nutrient solution and use it to control various equipment such as pumps, compressors, pressure reducing valves, and fans. 26a and 26b shown in FIG. 7 are temperature detectors installed for this purpose. It is also possible to detect the temperature of the nutrient solution heating and sterilization unit 7 during sterilization of the nutrient solution, and control the pump, compressor, pressure reducing valve, etc. so that the nutrient solution is heated to a temperature sufficient for sterilization. It is. Reference numeral 27 shown in FIG. 7 is a temperature detector installed for this purpose. Furthermore, it is also possible to detect both the temperature of the nutrient solution in the cultivation section and the nutrient solution in the sterilization section, and control various devices to maintain them at appropriate levels. However, the present invention is not limited to the various control target devices and control methods described above.
以上のようにこの発明によれば、養液の温度調
節を殺菌時においても、非殺菌時においても行う
ことができ、また非殺菌時の温度調節を加温殺菌
に用いたヒートポンプと同じヒートポンプにて行
えるように構成したので、装置が非常に安価にな
り、また、常時養液温度を適正に維持できる信頼
性の高い養液栽培装置が得られるという効果があ
る。
As described above, according to the present invention, the temperature of the nutrient solution can be adjusted both during sterilization and during non-sterilization, and the temperature adjustment during non-sterilization can be performed using the same heat pump used for heating sterilization. Since the system is configured so that it can be carried out, the cost of the apparatus becomes very low, and there is an effect that a highly reliable hydroponic system capable of constantly maintaining the temperature of the nutrient solution at an appropriate level can be obtained.
第１図Ａ，Ｂはそれぞれ従来の養液栽培装置を
示す構成図、第２図は本発明の１実施例による養
液栽培装置を示す構成図、第３図は第２図におい
て示した実施例の養液栽培装置の動作を説明する
ための部分図、第４図、第５図、第６図、第７図
は本発明の他の実施例による養液栽培装置を示す
構成図である。
１……作物、２……栽培槽、３……養液タン
ク、４……養液、５，５ａ……養液循環路、６，
６ａ……ポンプ、７……養液加温殺菌部、８……
養液冷却部、９……養液放熱部、１１……ヒート
ポンプ、１２……主放熱部、１３……主吸熱部、
１４……冷媒蒸気圧縮機、１５……減圧弁、１６
……冷媒循環路、１７……養液温度調節部、１８
……養液温度調節用副熱源部、２０……三方弁、
２１……四方弁、２３……副熱源部。なお、図
中、同一符号は同一、又は相当部分を示す。
FIGS. 1A and B are block diagrams showing conventional hydroponic cultivation equipment, FIG. 2 is a block diagram showing a hydroponic cultivation apparatus according to an embodiment of the present invention, and FIG. FIGS. 4, 5, 6, and 7 are partial diagrams for explaining the operation of the example hydroponic cultivation device, and are configuration diagrams showing a hydroponic cultivation device according to other embodiments of the present invention. . 1... Crop, 2... Cultivation tank, 3... Nutrient tank, 4... Nutrient solution, 5, 5a... Nutrient solution circulation path, 6,
6a...pump, 7...nutrient solution heating sterilization section, 8...
Nutrient solution cooling part, 9... Nutrient solution heat radiation part, 11... Heat pump, 12... Main heat radiation part, 13... Main heat absorption part,
14... Refrigerant vapor compressor, 15... Pressure reducing valve, 16
... Refrigerant circulation path, 17 ... Nutrient solution temperature control section, 18
...Auxiliary heat source section for adjusting the temperature of the nutrient solution, 20...Three-way valve,
21... Four-way valve, 23... Secondary heat source section. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.
Claims (1)
記養液加温殺菌部によつて加温された養液を一次
冷却する養液放熱部と、上記養液放熱部で一次冷
却された養液を作物栽培に適した温度まで二次冷
却する養液冷却部を有する養液循環路と、上記養
液加温殺菌部と熱交換する主放熱部を放熱源と
し、上記養液冷却部と熱交換する主吸熱部を吸熱
源とする主冷媒回路を有するヒートポンプとを備
えた養液栽培装置において、上記ヒートポンプの
放熱源あるいは吸熱源として機能する、上記主放
熱部および主吸熱部とは別に設けた１個または２
個の副熱源部と、上記ヒートポンプに設けた上記
主放熱部、主吸熱部、副熱源部の内の２つを放熱
源あるいは吸熱源とする副冷媒回路と、養液の殺
菌を行わない時には上記副冷媒回路中の副熱源部
と養液循環路中に別に設けた養液温度調節部ある
いは上記養液加温殺菌部、上記養液冷却部のいず
れかと熱交換して上記養液を加温あるいは冷却
し、養液温度を作物栽培に最適な温度に維持する
切換弁とを具備したことを特徴とする養液栽培装
置。 ２ 養液栽培装置内に作物を栽培するための栽培
槽と、養液を収容するための養液タンクと、上記
栽培槽および養液タンク間で養液を循環させるた
めの養液循環路とを備え、該養液循環路中に養液
加温殺菌部、養液放熱部、養液冷却部、養液温度
調節部を設けたことを特徴とする特許請求の範囲
第１項記載の養液栽培装置。 ３ 養液栽培装置内に作物を栽培するための栽培
槽と、養液を収容するための養液タンクと、上記
栽培槽および養液タンク間で養液を循環させるた
めの養液循環路とを備え、上記養液タンクからそ
の内部の養液をとり出して、再び上記養液タンク
に戻る別養液循環路中に養液加温殺菌部、養液放
熱部、養液冷却部、養液温度調節部を設けたこと
を特徴とする特許請求の範囲第１項記載の養液栽
培装置。 ４ ヒートポンプが多段式ヒートポンプであるこ
とを特徴とする特許請求の範囲第１項乃至第３項
のいずれか一項に記載の養液栽培装置。 ５ 栽培部での養液の温度を検知するための温度
検出器を備えたことを特徴とする特許請求の範囲
第１項乃至第４項のいずれか一項に記載の養液栽
培装置。 ６ 殺菌時において養液加温殺菌部での養液の温
度を検知するための温度検出器を備えたことを特
徴とする特許請求の範囲第１項乃至第４項のいず
れか一項に記載の養液栽培装置。[Scope of Claims] 1. A nutrient solution heating and sterilizing section that heats and sterilizes a nutrient solution; a nutrient solution heat radiating section that primarily cools the nutrient solution heated by the nutrient solution heating and sterilizing section; A nutrient solution circulation path having a nutrient solution cooling section that secondarily cools the nutrient solution that has been primarily cooled in the nutrient solution heat radiating section to a temperature suitable for crop cultivation, and a main heat radiating section that exchanges heat with the nutrient solution heating and sterilization section. In a hydroponic cultivation apparatus comprising a heat pump having a main refrigerant circuit as a heat radiation source and a main heat absorption part that exchanges heat with the nutrient solution cooling part as a heat absorption source, the above-mentioned hydroponic cultivation device functions as a heat radiation source or heat absorption source of the heat pump. 1 or 2 units installed separately from the main heat radiation section and main heat absorption section
and a sub-refrigerant circuit which uses two of the main heat radiation part, main heat absorption part, and sub heat source part provided in the heat pump as heat radiation sources or heat absorption sources, and when the nutrient solution is not sterilized. The nutrient solution is heated by exchanging heat with either the nutrient solution temperature control section, the nutrient solution heating sterilization section, or the nutrient solution cooling section provided separately in the auxiliary heat source section in the auxiliary refrigerant circuit and the nutrient solution circulation path. A hydroponic cultivation device characterized by comprising a switching valve that heats or cools the nutrient solution and maintains the temperature of the nutrient solution at the optimum temperature for crop cultivation. 2 A cultivation tank for cultivating crops in a hydroponic cultivation device, a nutrient solution tank for storing a nutrient solution, and a nutrient solution circulation path for circulating the nutrient solution between the cultivation tank and the nutrient solution tank. The nutrient solution according to claim 1, further comprising a nutrient solution heating sterilization section, a nutrient solution heat radiation section, a nutrient solution cooling section, and a nutrient solution temperature adjustment section in the nutrient solution circulation path. Hydroponic equipment. 3 A cultivation tank for cultivating crops in a hydroponic cultivation device, a nutrient solution tank for storing a nutrient solution, and a nutrient solution circulation path for circulating the nutrient solution between the cultivation tank and the nutrient solution tank. A nutrient solution heating sterilization section, a nutrient solution heat dissipation section, a nutrient solution cooling section, and a nutrient solution circulation path that take out the nutrient solution inside the nutrient solution tank and return it to the nutrient solution tank are provided. The hydroponic cultivation apparatus according to claim 1, further comprising a liquid temperature adjustment section. 4. The hydroponic cultivation apparatus according to any one of claims 1 to 3, wherein the heat pump is a multistage heat pump. 5. The hydroponic cultivation apparatus according to any one of claims 1 to 4, comprising a temperature detector for detecting the temperature of the nutrient solution in the cultivation section. 6. According to any one of claims 1 to 4, the method includes a temperature detector for detecting the temperature of the nutrient solution in the nutrient solution heating sterilization section during sterilization. hydroponic equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59039778A JPS60184333A (en) | 1984-03-02 | 1984-03-02 | Nutritive solution culture apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59039778A JPS60184333A (en) | 1984-03-02 | 1984-03-02 | Nutritive solution culture apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60184333A JPS60184333A (en) | 1985-09-19 |
| JPH0217135B2 true JPH0217135B2 (en) | 1990-04-19 |
Family
ID=12562392
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59039778A Granted JPS60184333A (en) | 1984-03-02 | 1984-03-02 | Nutritive solution culture apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60184333A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2512033Y2 (en) * | 1991-12-05 | 1996-09-25 | 株式会社四国総合研究所 | Hydroponics equipment |
| JPH06303861A (en) * | 1993-04-26 | 1994-11-01 | Nippon Keori Kk | Method for temperature control of culture solution in water culture greenhouse |
| JP2008043781A (en) * | 2007-09-27 | 2008-02-28 | Sanyo Electric Co Ltd | Sterilization processing device using heat pump |
| JP4976994B2 (en) * | 2007-11-29 | 2012-07-18 | カヤバ工業株式会社 | Water pressure system and food processing equipment |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5939777A (en) * | 1982-08-28 | 1984-03-05 | 東京窯業株式会社 | Mortar for thermal construction |
-
1984
- 1984-03-02 JP JP59039778A patent/JPS60184333A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5939777A (en) * | 1982-08-28 | 1984-03-05 | 東京窯業株式会社 | Mortar for thermal construction |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60184333A (en) | 1985-09-19 |
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