JPS6128608B2 - - Google Patents
Info
- Publication number
- JPS6128608B2 JPS6128608B2 JP10380679A JP10380679A JPS6128608B2 JP S6128608 B2 JPS6128608 B2 JP S6128608B2 JP 10380679 A JP10380679 A JP 10380679A JP 10380679 A JP10380679 A JP 10380679A JP S6128608 B2 JPS6128608 B2 JP S6128608B2
- Authority
- JP
- Japan
- Prior art keywords
- slurry
- hemihydrate gypsum
- type hemihydrate
- gypsum
- added
- 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
Links
- 239000013078 crystal Substances 0.000 claims description 37
- ZOMBKNNSYQHRCA-UHFFFAOYSA-J calcium sulfate hemihydrate Chemical compound O.[Ca+2].[Ca+2].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O ZOMBKNNSYQHRCA-UHFFFAOYSA-J 0.000 claims description 28
- 239000002002 slurry Substances 0.000 claims description 19
- 238000007254 oxidation reaction Methods 0.000 claims description 12
- GBAOBIBJACZTNA-UHFFFAOYSA-L calcium sulfite Chemical compound [Ca+2].[O-]S([O-])=O GBAOBIBJACZTNA-UHFFFAOYSA-L 0.000 claims description 11
- 235000010261 calcium sulphite Nutrition 0.000 claims description 11
- 230000003647 oxidation Effects 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 9
- 239000003607 modifier Substances 0.000 claims description 8
- 239000004571 lime Substances 0.000 claims description 6
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 5
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 150000003839 salts Chemical class 0.000 claims description 5
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 229910052815 sulfur oxide Inorganic materials 0.000 claims description 4
- 229910052602 gypsum Inorganic materials 0.000 description 11
- 239000010440 gypsum Substances 0.000 description 11
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 8
- 239000002994 raw material Substances 0.000 description 8
- 150000004683 dihydrates Chemical class 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 5
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- 238000006477 desulfuration reaction Methods 0.000 description 4
- 230000023556 desulfurization Effects 0.000 description 4
- 239000003546 flue gas Substances 0.000 description 4
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 description 4
- 239000001509 sodium citrate Substances 0.000 description 4
- 238000007664 blowing Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000010979 pH adjustment Methods 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- TXKMVPPZCYKFAC-UHFFFAOYSA-N disulfur monoxide Inorganic materials O=S=S TXKMVPPZCYKFAC-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 235000012204 lemonade/lime carbonate Nutrition 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Landscapes
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
本発明は排ガス中のいおう酸化物と石灰あるい
は炭酸カルシウムスラリー（以下、石灰スラリー
という）を主原料とし、これを所定条件下で反応
処理することにより、付加価値の高い柱状結晶α
型半水石こう、特に結晶形の揃つた六角柱状α型
半水石こうを製造する方法に関する。従来より周
知のように石こうはその結晶変態により７種類に
分類されており、その種別性状に応じて適当な用
途に利用されている。
これらの石こうのうちで、半水石こうは、α型
半水石こうとβ型半水石こうの２種類があり更
に、α型半水石こうはその結晶形の相違により柱
状結晶のものと、針状結晶のものとに大別される
が、これらのうち、柱状結晶α型半水石こうは水
和硬化すると、高強度を発揮する硬化体になるも
のであり、第１図の走査型電子顕微鏡写真に示す
ような柱状結晶形を有しており、その乾燥圧縮強
度は第１表に示すように334Kg/cm2でβ型半水石こ
うと比較してかなり大きいことから歯科用、精密
賦形型用などの高級な用途に賞用されている。こ
の柱状結晶α型半水石こうは塊状の天燃石こう
（二水石こう）あるいは粉末の副産石こう（二水
石こう）を加圧成型ないし造粒したものを原料と
して、これを密閉型焼成がまで媒晶剤とともに加
圧加熱処理し、ろ過乾燥後微粉砕することにより
得られるが、昨今の排煙脱硫技術の発展により排
煙脱硫工程で亜硫酸カルシウムを主原料とし、こ
れを適当な条件下で反応処理することによつて、
製造する方法も幾多、開発されている。
たとえば、特開昭49−83695号によれば亜硫酸
石灰のスラリーを加圧下で100〜140℃、PH４内外
で空気吹込により酸化処理して一旦、二水石こう
とし、これをα型半水石こうに転化する方法を開
示しているが、この方法により得られるα型半水
石こうとは第２図に示すようなものであつて、板
状結晶に混じつて柱状結晶も存在するが、その柱
状結晶も厚みの薄いものしか生成しておらず、前
述の如く、天然石こう（二水石こう）等より製造
した柱状結晶α型半水石こうに比べてその乾燥圧
縮強度はかなり低いものであるところから、排煙
脱硫法の利用により大きい乾燥圧縮強度を示す結
晶形の揃つた柱状結晶α型半水石こうを製造する
方法の出現が待ち望まれていた。
本発明はこの期待に応じるもので大きい乾燥圧
縮強度を示す結晶形の揃つた柱状結晶、特に六角
柱状結晶α型半水石こうのみを高収率に安定供給
する方法を提供するもので、以下、その構成を述
べる。
本発明の製造工程を大別すると、排ガス中のい
おう酸化物の冷却工程、吸収工程、PH調整工程、
酸化撹拌工程、ろ過乾燥工程の５工程より構成さ
れる。
冷却工程、及び吸収工程であるが、これは石灰
−石こう法排煙脱硫の従来技術で行う。
即ち、いおう酸化物を含む排ガス温度を約60℃
に下げてから、この排ガスを石灰スラリーと接触
させていおう酸化物を吸収させ、スラリー濃度が
約10wt％の亜硫酸カルシウムスラリーを生成せ
しめる。
次にPH調整工程であるが、上記亜硫酸カルシウ
ムスラリーに柱状結晶の生成に有利な媒晶剤を
0.01〜1wt％添加し、その後、該亜硫酸カルシウ
ムスラリーにいおう酸化物を含む排ガスと接触さ
せるか硫酸を加えてPH３〜４に調整する。この
際、反応時間を短縮するため、酸化促進と柱状の
結晶成長を助けるための触媒である金属塩を、
0.01〜0.1wt％添加すると効果的である。
次いで、酸化工程ではPH調整後のスラリーを温
度120〜150℃、好ましくは120〜130℃、圧力２
Kg/cm2以上の加圧下で酸素ガスあるいは空気を送
入して酸化せしめる。
さて、上記酸化撹拌工程で既に六角柱状結晶α
型半水石こうが析出生成しているが、更に次のろ
過乾燥工程で、生成した六角柱状結晶α型半水石
こうの水和を防ぐため、熱時に急速ろ過または分
離し、洗滌後、直ちに乾燥することにより目的と
するα型半水石こうを得ることができる。
この際、乾燥条件として90℃以上、好ましくは
120〜130℃で急速に行われることが望ましく、分
離液と洗滌液はそれらとともに媒晶剤と金属塩の
有効利用をはかるため、石灰スラリーを調整する
際に再利用することができる。
又、第２表から明らかなようにNo.1ではPH
3.0、120℃の条件下で２時間、酸化反応させる
と、α型半水石こう（針状結晶）が生成するが、
No.4のように同条件で媒晶剤としてクエン酸ナ
トリウムを添加すると、４時間の酸化反応ののち
に、二水石こうに混在して柱状結晶α型半水石こ
うが生成することから媒晶剤は柱状結晶の生成を
助長するが、反応速度を抑制する傾向があること
がわかる。
一方、No.1と同条件で媒晶剤のほかに硫酸ニ
ツケルを添加すると、反応が速くなるが、これは
硫酸ニツケルが酸化触媒としての効果をもち、酸
化を促進するのに有効であることも理解できる。
以下、本発明の実施例を述べる。
実施例 １
亜硫酸カルシウム半水塩を原料とし、原料50ｇ
を450mlに加えて10wt％濃度の亜硫酸カルシウム
スラリーとし、これに媒晶剤としてクエン酸ナト
リウム0.17wt％、金属塩として硫酸ニツケル
0.1wt％を加え、これに硫酸を適量加えてPH3.0に
し、温度130℃、圧力２Kg/cm2800r.p.mでスラリ
ー全体を空気吹込みにより２時間、酸化を行つ
た。
酸化終了後、熱時にろ過洗滌し約90℃で乾燥し
て結晶形の揃つた六角柱状結晶α型半水石こうを
得た。（第３図を参照）
尚、得られた六角柱状結晶α型半水石こうの乾
燥圧縮強度は340Kg/cm2と強い。（第１表を参照）
実施例 ２
亜硫酸カルシウム半水塩を原料とし、原料25ｇ
を水475mlに加えて5wt％濃度の亜硫酸カルシウ
ムスラリーとし、これに媒晶剤としてクエン酸ナ
トリウム0.1wt％、金属塩として硫酸ニツケル
0.1wt％を加え、これに硫酸を適量加えてPH3.0に
し、温度130℃、圧力２Kg/cm2の条件下、空気吹込
により１時間、酸化を行つた。
酸化終了後、熱時にろ過洗滌し、約90℃で乾燥
して実施例１とほぼ同様の結晶形の揃つた六角柱
状結晶α型半水石こうを得た。（第４図を参照）
次に上述実施例１及び２に対する比較例として
同実施例１で硫酸ニツケルを添加しない場合を掲
げる。
比較例
亜硫酸カルシウム半水塩を原料とし、原料50ｇ
を水450mlに加えて10wt％濃度の亜硫酸カルシウ
ムスラリーとし、これに媒晶剤としてクエン酸ナ
トリウム0.17wt％のみを添加し、これに硫酸を適
量加えてPH3.0にし、温度130℃、圧力２Kg/cm2の
条件下で、実施例１と同様の処理を施こして得ら
れた生成物は、実験操作の巧拙にもよるが実施例
１のような六角柱状のα型半水石こうではなく、
板状結晶や針状結晶のα型半水石こうをも含む混
合物であつた。（図面なし）
The present invention uses sulfur oxides in exhaust gas and lime or calcium carbonate slurry (hereinafter referred to as lime slurry) as the main raw materials, and by reacting them under predetermined conditions, columnar crystals α with high added value are produced.
The present invention relates to a method for producing type hemihydrate gypsum, particularly hexagonal columnar α-type hemihydrate gypsum with uniform crystal shapes. As is well known, gypsum is classified into seven types according to its crystal transformation, and is used for appropriate purposes depending on the type and properties. Among these types of gypsum, there are two types of hemihydrate gypsum, α-type hemihydrate gypsum and β-type hemihydrate gypsum.Furthermore, α-type hemihydrate gypsum is divided into columnar crystals and acicular crystals due to the difference in crystal form. Among these, α-type hemihydrate gypsum with columnar crystals becomes a hardened product that exhibits high strength when hardened by hydration, as shown in the scanning electron micrograph in Figure 1. It has a columnar crystal shape as shown in Table 1, and its dry compressive strength is 334 kg/cm 2 as shown in Table 1, which is considerably higher than β-type hemihydrate gypsum, making it suitable for dental use and precision shaping. It is prized for high-grade purposes such as personal use. This columnar crystal α-type hemihydrate gypsum is produced by pressure molding or granulation of bulk natural gypsum (dihydrate gypsum) or powdered by-product gypsum (dihydrate gypsum). It is obtained by pressurizing and heating treatment with a modifier, filtering and drying, and then pulverizing. However, with the recent development of flue gas desulfurization technology, calcium sulfite is used as the main raw material in the flue gas desulfurization process, and it is processed under appropriate conditions. By reaction treatment,
Many manufacturing methods have also been developed. For example, according to JP-A No. 49-83695, a slurry of sulfite lime is oxidized under pressure at 100 to 140℃ with air blowing inside and outside PH4 to form dihydrate gypsum, which is then converted into α-type hemihydrate gypsum. The α-type hemihydrate gypsum obtained by this method is as shown in Figure 2, and columnar crystals are present in addition to plate crystals. However, as mentioned above, the dry compressive strength is considerably lower than that of columnar crystal α-type hemihydrate gypsum produced from natural gypsum (dihydrate gypsum), etc. The emergence of a method for producing α-type hemihydrate gypsum with columnar crystals with uniform crystal shapes that exhibits high dry compressive strength by utilizing flue gas desulfurization has been eagerly awaited. The present invention meets this expectation and provides a method for stably supplying only columnar crystals with a uniform crystal shape, particularly hexagonal columnar crystals α-type hemihydrate gypsum, with a high dry compressive strength, in a high yield. I will describe its structure. The manufacturing process of the present invention can be roughly divided into a cooling process for sulfur oxides in exhaust gas, an absorption process, a pH adjustment process,
It consists of 5 steps: oxidation stirring step and filtration drying step. The cooling step and the absorption step are performed using conventional techniques of lime-gypsum flue gas desulfurization. In other words, the temperature of the exhaust gas containing sulfur oxides is about 60℃.
The exhaust gas is then brought into contact with lime slurry to absorb the oxides and produce a calcium sulfite slurry with a slurry concentration of about 10 wt%. Next is the pH adjustment process, in which a modifier that is advantageous for the formation of columnar crystals is added to the calcium sulfite slurry.
After adding 0.01 to 1 wt%, the calcium sulfite slurry is brought into contact with exhaust gas containing sulfur oxide or sulfuric acid is added to adjust the pH to 3 to 4. At this time, in order to shorten the reaction time, a metal salt, which is a catalyst to promote oxidation and support columnar crystal growth, was added.
It is effective to add 0.01 to 0.1 wt%. Next, in the oxidation step, the slurry after pH adjustment is heated at a temperature of 120 to 150°C, preferably 120 to 130°C, and a pressure of 2.
Oxygen gas or air is introduced under pressure of Kg/cm 2 or more to oxidize. Now, in the above oxidation stirring step, the hexagonal columnar crystal α has already been formed.
Type hemihydrate gypsum is precipitated and formed, but in order to prevent hydration of the hexagonal columnar crystal α type hemihydrate gypsum that is formed in the next filtration and drying process, it is rapidly filtered or separated when heated, and dried immediately after washing. By doing so, the desired α-type hemihydrate gypsum can be obtained. At this time, the drying conditions are 90℃ or higher, preferably
It is desirable that the process be carried out rapidly at 120-130°C, and the separation liquid and washing liquid can be reused when preparing the lime slurry, in order to effectively utilize the crystal modifier and metal salt. Also, as is clear from Table 2, No. 1 has a PH
When oxidized for 2 hours at 3.0°C and 120°C, α-type hemihydrate gypsum (acicular crystals) is produced.
When sodium citrate is added as a crystallizing agent under the same conditions as in No. 4, after 4 hours of oxidation reaction, columnar crystals α-type hemihydrate gypsum is generated mixed with dihydrate gypsum, resulting in the formation of a medium crystal. It can be seen that the agent promotes the formation of columnar crystals, but tends to suppress the reaction rate. On the other hand, if nickel sulfate is added in addition to the modifier under the same conditions as No. 1, the reaction will be faster, but this is because nickel sulfate has the effect of an oxidation catalyst and is effective in promoting oxidation. I can also understand. Examples of the present invention will be described below. Example 1 Calcium sulfite hemihydrate is used as raw material, 50g of raw material
was added to 450ml to make a 10wt% calcium sulfite slurry, and to this was added 0.17wt% sodium citrate as a modifier and nickel sulfate as a metal salt.
0.1 wt% was added thereto, and an appropriate amount of sulfuric acid was added to adjust the pH to 3.0, and the entire slurry was oxidized at a temperature of 130° C. and a pressure of 2 Kg/cm 2 at 800 rpm for 2 hours by blowing air. After the oxidation was completed, it was filtered and washed while hot, and dried at about 90°C to obtain α-type hemihydrate gypsum with hexagonal columnar crystals. (See Figure 3) The dry compressive strength of the obtained hexagonal columnar crystal α-type hemihydrate gypsum is as strong as 340 Kg/cm 2 . (See Table 1) Example 2 Calcium sulfite hemihydrate is used as raw material, 25g of raw material
was added to 475ml of water to make a 5wt% calcium sulfite slurry, and to this was added 0.1wt% of sodium citrate as a modifier and nickel sulfate as a metal salt.
0.1 wt% was added thereto, and an appropriate amount of sulfuric acid was added to adjust the pH to 3.0, and oxidation was carried out for 1 hour by blowing air under conditions of a temperature of 130°C and a pressure of 2 kg/cm 2 . After the oxidation was completed, it was filtered and washed while hot, and dried at about 90°C to obtain hexagonal columnar crystal α-type hemihydrate gypsum with almost the same crystal shape as in Example 1. (See FIG. 4) Next, as a comparative example for Examples 1 and 2 described above, a case where nickel sulfate is not added in Example 1 is listed. Comparative example Calcium sulfite hemihydrate is used as raw material, 50g of raw material
was added to 450ml of water to make a 10wt% calcium sulfite slurry, to which only 0.17wt% of sodium citrate was added as a modifier, and an appropriate amount of sulfuric acid was added to make the pH 3.0, at a temperature of 130℃ and a pressure of 2Kg. The product obtained by performing the same treatment as in Example 1 under the conditions of /cm 2 is not the hexagonal columnar α-type hemihydrate gypsum as in Example 1, although it depends on the skill of the experimental operation. ,
The mixture also contained α-type hemihydrate gypsum in the form of plate-like and needle-like crystals. (No drawing)
【表】【table】
第１図〜第４図は図面に代る走査型電子顕微鏡
写真であり、第１図は市販の柱状結晶α型半水石
こう、第２図は特開昭49−83695号により得られ
るα型半水石こう、第３図は実施例１により得ら
れる六角柱状結晶α型半水石こう、第４図は実施
例２により得られる六角柱状結晶α型半水石こう
を示す。
Figures 1 to 4 are scanning electron micrographs in place of drawings. Figure 1 is a commercially available columnar crystal α-type hemihydrate gypsum, and Figure 2 is an α-type obtained from JP-A-49-83695. FIG. 3 shows α-type hemihydrate gypsum with hexagonal columnar crystals obtained in Example 1, and FIG. 4 shows α-type hemihydrate gypsum with hexagonal columnar crystals obtained in Example 2.
Claims (1)
収させてスラリー濃度が約10wt％の亜硫酸カル
シウムスラリーとする工程と、該スラリーに柱状
結晶の生成に有利な媒晶剤ならびに酸化促進と結
晶の成長を助長する可溶性金属塩を添加したの
ち、PH３〜４にPH調整する工程と、該PH調整され
たスラリーを約120〜150℃、２Kg/cm2以上の加熱
加圧下で酸化する工程と、該酸化処理されたスラ
リーを熱時に急速ろ過したのち、90℃以上で熱風
乾燥する工程とから成ることを特徴とする六角柱
状結晶α型半水石こうの製造法。1 A process in which sulfur oxides in exhaust gas are absorbed into lime slurry to form calcium sulfite slurry with a slurry concentration of approximately 10 wt%, and the slurry is treated with a modifier that is advantageous for the formation of columnar crystals, as well as oxidation promotion and crystal growth. A step of adjusting the pH to 3 to 4 after adding a soluble metal salt to promote the oxidation; A method for producing α-type hemihydrate gypsum with hexagonal columnar crystals, which comprises the steps of rapidly filtering the treated slurry while hot, and then drying it with hot air at 90°C or higher.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10380679A JPS5532789A (en) | 1979-08-14 | 1979-08-14 | Production of hexagonal prismatic crystal alpha-type hemihydrate gypsum |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10380679A JPS5532789A (en) | 1979-08-14 | 1979-08-14 | Production of hexagonal prismatic crystal alpha-type hemihydrate gypsum |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP50039673A Division JPS5838363B2 (en) | 1975-03-31 | 1975-03-31 | Alfa Gatahansuisetsukou Oseizosurhouhou |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5532789A JPS5532789A (en) | 1980-03-07 |
| JPS6128608B2 true JPS6128608B2 (en) | 1986-07-01 |
Family
ID=14363638
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10380679A Granted JPS5532789A (en) | 1979-08-14 | 1979-08-14 | Production of hexagonal prismatic crystal alpha-type hemihydrate gypsum |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5532789A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101501432B (en) | 2006-08-15 | 2011-10-12 | 巴斯夫欧洲公司 | Method for the production of dry free-flowing hydrophobin preparations |
| CN101679063A (en) * | 2007-05-24 | 2010-03-24 | 巴斯夫欧洲公司 | Use of hydrophobins as additives in the crystallization of solids |
-
1979
- 1979-08-14 JP JP10380679A patent/JPS5532789A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5532789A (en) | 1980-03-07 |
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