【発明の詳細な説明】[Detailed description of the invention]
本発明は液体肥料用原体に関する。
液体肥料用原体は、従来の液体肥料に比し、溶
媒の水が存在しないので高成分であること、およ
びこれからくる輸送費、包装費等が割安になる等
の利点があるが、固結を起こし易いために取り扱
い上において困難を来たす場合がしばしばある。
従来、周知の肥料の固結防止方法としては珪藻
土、タルク、ベントナイト、酸性白土、炭酸マグ
ネシウム、水酸化マグネシウム等の微粉末を添加
する方法、または、リン酸第二鉄塩を添加する方
法（特公昭51−40877）、または、脂肪酸アミドと
脂肪族アミドとを添加する方法（特公昭53−
8668）など種々の方法があるが、これらの固結防
止剤を液体肥料用原体に適用することは製品の使
用目的によつては好ましくなく、例えば、液体肥
料用原体は水に溶融させた後、噴霧器等を用いて
葉面散布されることが多く、この場合従来の固結
防止剤のような、そのほとんどが水に難溶性か、
あるいは不溶性のものを使用したときには噴霧器
等のスプレーノズルの閉塞及びスケールの付着等
の悪影響を与えるので使用出来ないこともある。
従つて、液体肥料用原体の固結防止剤としては水
溶性の高いものが要望されていた。
本発明者等は液体肥料用原体の固結防止に関し
て種々検討し結果、ピロリン酸カリを液体肥料用
原体に少量添加することによつてすぐれた固結防
止効果が得られ、しかも製品の使用において何ら
の悪影響をも及ぼさないことを見い出した。
すなわち、本発明は、硝安、尿素、硫安、塩
安、１燐安、２燐安、塩化カリおよび硫酸カリの
少なくとも１種よりなる液体肥料用原体にピロリ
ン酸カリを１〜10重量％含有する未焼成の液体肥
料用原体である。
本発明において対象となる液体肥料用原体とし
ては硝安、尿素、硫安、塩安、１燐安、２燐安、
塩化カリ、硫酸カリ、並びにこれらの肥料物質の
組み合わせにより数種の肥料成分を含む配合肥
料、あるいはこれらにマグネシウム、硼素、マン
ガン等植物の生育に必要な要素を含有させた粉粒
体組成物が挙げられる。
本発明において使用される固結防止剤としての
ピロリン酸カリは純粋である必要はなく、工業用
として市販されているもので差し支えない。
本発明による固結防止剤は少量の添加により充
分満足する固結防止効果が得られるが、その添加
量があまり少な過ぎると固結防止効果が不充分で
あり、またその添加量が多過ぎても固結防止効果
の著るしい向上は望めず経済的に不利となるの
で、通常は液体肥料用原体に対いて１〜10重量
％、好ましくは３〜８重量％の範囲において使用
される。
添加方法は特に制限されることはなく、常法の
手段を用いて行なわれる。最も一般的には、回転
円筒または回転皿等の装置を用いて液体肥料用原
体を転動させながら、これにピロリン酸カリを添
加混合する方法が採られる。
本発明において、ピロリン酸カリを添加混合し
た肥料用原体は焼成せずに液体肥料用原体として
用いる。
このように液体肥料用原体にピロリン酸カリを
添加し処理する時は、従来知られている固結防止
剤に比し極めて優れた固結防止効果が期待でき
る。
本発明による固結防止剤の固結防止効果がどの
ような機構によつて生ずるかは明らかではない
が、肥料の固結性が一般に水分の吸収に起因して
隣接する粒子間に生ずる飽和溶液から大気の状態
変化に際して析出する結晶が各粒子間の架橋にな
るためであると考えられているので、本発明方法
によればピロリン酸カリの粉末が肥料の粒子相互
間の接触を妨げるのみでなく、ピロリン酸カリが
粒子表面の水分を吸収してピロリン酸カリの水和
物を生成するので、肥料は乾燥状態を保つことに
なり、かつ生成するピロリン酸カリの水和物の非
固結性物質で安定であるために、これらの作用が
合体相乗されて極めて優れた固結防止効果を示す
ものと推定される。
従つて、本発明方法によれば肥料の固結の原因
となる粒子の接触と、吸湿性に対して同時に対処
できることになる。
以下に実施例を挙げて本発明を更に具体的に説
明するが、本発明はこれら実施例のみに限定され
るものではない。
なお、実施例中の％および部は特記しない限り
すべて重量％および重量部を示す。
実施例 １
結晶状硝安（アンモニア態窒素：17.39％、硝
酸態窒素：17.39％、）495部、結晶状硫安（アン
モニア態窒素：21.10％）91部、結晶状１燐安
（アンモニア態窒素：12.03％、水溶性燐酸：
60.89％）123部、結晶状塩化カリ（水溶性カリ：
62.0％）207部を回転皿を用いて転動させながら、
粉末状ピロリン酸カリ（水溶性燐酸：41.74％、
水溶性カリ：55.22％の工業用市販品）を常温で
添加し、５分間転動処理して硝安系液体肥料用原
体を得た後、固結度を測定した。結果を第一表に
示す。
なお、固結度の測定は次の方法で行なつた。す
なわち、内径32mm、高さ30mmのポリ塩化ビニル製
円筒内に、試料を充填し、外径30mm、高さ10mmの
ポリ塩化ビニル製円柱をのせ、その上に１Kgの荷
重をかけ、ポリエチレン袋で包んだ後、温度30
℃、湿度80％の恒温恒湿槽内に７日間放置する。
放置後、円筒内の試料を取り出し、このものの圧
力破壊強度を測定し、固結度を推定した。
比較例 １〜４
実施例１と同一の硝安系液体肥料用原体に、ピ
ロリン酸カリを添加しない場合、及び周知の固結
防止剤：珪藻土、タルク、酸性白土を添加した場
合について、実施例１と同一の操作を行ない、固
結度を測定した。これらの結果を第１表に示す。
The present invention relates to a raw material for liquid fertilizer. Compared to conventional liquid fertilizers, liquid fertilizer ingredients have the advantage of being high-component because there is no water as a solvent, and that the transportation costs and packaging costs will be lower. It is often difficult to handle because of the tendency to cause Conventionally known methods for preventing caking of fertilizers include adding fine powders of diatomaceous earth, talc, bentonite, acid clay, magnesium carbonate, magnesium hydroxide, etc., or adding ferric phosphate salts (especially Publication No. 51-40877) or a method of adding fatty acid amide and aliphatic amide (Japanese Patent Publication No. 53-40877)
There are various methods such as 8668), but it is not preferable to apply these anti-caking agents to liquid fertilizer ingredients depending on the intended use of the product. After that, they are often sprayed on the leaves using a sprayer, etc. In this case, most of them are poorly soluble in water, such as conventional anti-caking agents, or
Alternatively, when an insoluble material is used, it may not be possible to use it because it causes adverse effects such as clogging of the spray nozzle of the atomizer and the adhesion of scale.
Therefore, there has been a demand for highly water-soluble anti-caking agents for liquid fertilizer ingredients. The present inventors have conducted various studies regarding the prevention of caking of liquid fertilizer ingredients, and have found that by adding a small amount of potassium pyrophosphate to liquid fertilizer ingredients, an excellent caking prevention effect can be obtained. It has been found that it does not have any adverse effects when used. That is, the present invention provides a liquid fertilizer base material containing at least one of ammonium nitrate, urea, ammonium sulfate, ammonium chloride, monoammonium phosphorus, diammonium phosphorus, potassium chloride, and potassium sulfate, containing 1 to 10% by weight of potassium pyrophosphate. It is a raw material for unfired liquid fertilizer. In the present invention, the active ingredients for liquid fertilizers include ammonium nitrate, urea, ammonium sulfate, ammonium chloride, ammonium phosphorus, ammonium diphosphorus,
Potassium chloride, potassium sulfate, and combination fertilizers containing several types of fertilizer components made from a combination of these fertilizer substances, or granular compositions containing elements necessary for plant growth such as magnesium, boron, and manganese are available. Can be mentioned. Potassium pyrophosphate used as an anti-caking agent in the present invention does not need to be pure, and may be commercially available for industrial use. The anti-caking agent according to the present invention can provide a satisfactory anti-caking effect by adding a small amount; however, if the amount added is too small, the anti-caking effect will be insufficient, and if the amount added is too large, the anti-caking effect will be insufficient. However, it cannot be expected to significantly improve the anti-caking effect and is economically disadvantageous, so it is usually used in the range of 1 to 10% by weight, preferably 3 to 8% by weight, based on the raw material for liquid fertilizer. . The method of addition is not particularly limited and may be carried out using conventional means. The most common method is to add and mix potassium pyrophosphate while rolling the liquid fertilizer raw material using a device such as a rotating cylinder or rotating plate. In the present invention, the raw material for fertilizer to which potassium pyrophosphate is added and mixed is used as a raw material for liquid fertilizer without being fired. When potassium pyrophosphate is added to a liquid fertilizer raw material and treated in this way, an extremely superior anti-caking effect can be expected compared to conventionally known anti-caking agents. Although it is not clear what mechanism causes the anti-caking effect of the anti-caking agent of the present invention, the caking properties of fertilizers are generally caused by a saturated solution that occurs between adjacent particles due to absorption of water. It is thought that this is because the crystals that precipitate when atmospheric conditions change form bridges between each particle. Therefore, according to the method of the present invention, the potassium pyrophosphate powder only prevents contact between fertilizer particles. Instead, the potassium pyrophosphate absorbs water on the surface of the particles and produces a hydrate of potassium pyrophosphate, so the fertilizer stays dry and the hydrate of the produced potassium pyrophosphate does not solidify. It is presumed that these effects are combined and synergized to exhibit an extremely excellent anti-caking effect, since it is a stable substance. Therefore, according to the method of the present invention, it is possible to simultaneously deal with particle contact, which causes fertilizer caking, and hygroscopicity. The present invention will be described in more detail with reference to Examples below, but the present invention is not limited only to these Examples. In addition, all % and parts in the examples indicate weight % and parts by weight unless otherwise specified. Example 1 495 parts of crystalline ammonium nitrate (ammonia nitrogen: 17.39%, nitrate nitrogen: 17.39%), 91 parts of crystalline ammonium sulfate (ammonia nitrogen: 21.10%), crystalline ammonium phosphorus (ammonia nitrogen: 12.03) %, water-soluble phosphoric acid:
60.89%) 123 parts, crystalline potassium chloride (water-soluble potassium:
62.0%) while rolling 207 parts using a rotating plate,
Powdered potassium pyrophosphate (water-soluble phosphoric acid: 41.74%,
Water-soluble potash: 55.22% industrial commercial product) was added at room temperature and rolled for 5 minutes to obtain an ammonium nitrate liquid fertilizer base material, and then the degree of caking was measured. The results are shown in Table 1. The degree of solidification was measured by the following method. That is, a sample was filled in a polyvinyl chloride cylinder with an inner diameter of 32 mm and a height of 30 mm, a polyvinyl chloride cylinder with an outer diameter of 30 mm and a height of 10 mm was placed on top, a load of 1 kg was applied, and a polyethylene bag was placed on top of the cylinder. After wrapping, temperature 30
Leave it in a constant temperature and humidity chamber at ℃ and 80% humidity for 7 days.
After standing, the sample inside the cylinder was taken out, the pressure fracture strength of this sample was measured, and the degree of consolidation was estimated. Comparative Examples 1 to 4 Examples were carried out in the case where potassium pyrophosphate was not added to the same ammonium nitrate-based liquid fertilizer base material as in Example 1, and when well-known anti-caking agents: diatomaceous earth, talc, and acid clay were added. The same operation as in 1 was performed to measure the degree of consolidation. These results are shown in Table 1.
【表】【table】
【表】
第１表に示すように、本発明の固結防止剤ピロ
リン酸カリを添加したときは、周知の固結防止剤
を添加したものに比し、極めて優れた固結防止効
果を期待できることが認められた。
実施例 ２
結晶状尿素（尿素態窒素：46.43％）371部、結
晶状硫安（アンモニア態窒素：21.10％）215部、
結晶状１燐安（アンモニア態窒素：12.03％、水
溶性燐酸：60.89％）123部、結晶状塩化カリ（水
溶性カリ：62.0％）207部を回転皿を用いて転動
させながら、粉末状ピロリン酸カリ（水溶性燐
酸：41.74％、水溶性カリ：55.22％の工業用市販
品）を常温で添加し、２分間転動処理して尿素系
液体肥料用原体を得た後、実施例１に記載した方
法と同一の方法で固結度を測定した。結果を第２
表に示す。
比較例 ５〜８
実施例２と同一の尿素系液体肥料用原体に、ピ
ロリン酸カリを添加しない場合、及び周知の固結
防止剤：珪藻土、タルク、酸性白土を添加した場
合について、実施例２と同一の操作を行ない、固
結度を測定した。これらの結果を第２表に示す。[Table] As shown in Table 1, when the anti-caking agent of the present invention, potassium pyrophosphate, is added, an extremely superior anti-caking effect is expected compared to when a well-known anti-caking agent is added. It was recognized that it could be done. Example 2 371 parts of crystalline urea (urea nitrogen: 46.43%), 215 parts of crystalline ammonium sulfate (ammonium nitrogen: 21.10%),
123 parts of crystalline ammonium phosphorus (ammonium nitrogen: 12.03%, water-soluble phosphoric acid: 60.89%) and 207 parts of crystalline potassium chloride (water-soluble potassium: 62.0%) were rolled in a powder form using a rotating plate. Potassium pyrophosphate (industrial commercial product with water-soluble phosphoric acid: 41.74%, water-soluble potassium: 55.22%) was added at room temperature and rolled for 2 minutes to obtain a raw material for urea-based liquid fertilizer. The degree of consolidation was measured by the same method as described in 1. Second result
Shown in the table. Comparative Examples 5 to 8 Examples were carried out in the case where potassium pyrophosphate was not added to the same urea-based liquid fertilizer bulk material as in Example 2, and when well-known anti-caking agents: diatomaceous earth, talc, and acid clay were added. The same operation as in 2 was performed to measure the degree of consolidation. These results are shown in Table 2.
【表】【table】