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JPS5499099A - Production of gypsum fine powder - Google Patents

Production of gypsum fine powder

Info

Publication number
JPS5499099A
JPS5499099A JP569778A JP569778A JPS5499099A JP S5499099 A JPS5499099 A JP S5499099A JP 569778 A JP569778 A JP 569778A JP 569778 A JP569778 A JP 569778A JP S5499099 A JPS5499099 A JP S5499099A
Authority
JP
Japan
Prior art keywords
gypsum
water
harden
under conditions
finely divided
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.)
Granted
Application number
JP569778A
Other languages
Japanese (ja)
Other versions
JPS6232131B2 (en
Inventor
Ryuhei Ueda
Yutaka Tanoe
Yasuhei Takeuchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kuraray Co Ltd
Original Assignee
Kuraray Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kuraray Co Ltd filed Critical Kuraray Co Ltd
Priority to JP569778A priority Critical patent/JPS5499099A/en
Publication of JPS5499099A publication Critical patent/JPS5499099A/en
Publication of JPS6232131B2 publication Critical patent/JPS6232131B2/ja
Granted legal-status Critical Current

Links

Landscapes

  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Abstract

PURPOSE:To produce finely divided gypsum powder contg. no coarse particles by treating gypsum to convert it into hemihydrate gypsum and/or anhydrous gypsum, followed by hydration under conditions which do not harden the treated gypsum. CONSTITUTION:Gypsum of grain size about 100-300 mu, e.g. gypsum from exhaust gas desulfurization or gypsum as by-product of phosphoric acid is calcined at 130- 200 deg.C to obtain hemihydrate gypsum, III-type anhydrous gypsum, II-type anhydrous gypsum or their mixt. The resulting gypsum is gradually charged into water at a rate below 20 g/min to 1 kg of water to carry out hydration under conditions which do not harden the gypsum, thus producing finely divided gypsum of needle-like crystal. The shape of the gypsum particles varies slightly depending on the temp. of water e.g. the length is about 10-20 mu and 40-70 mu, and the width is about 2-5 mu and 5-10 mu at around 20 deg.C and 60 deg.C, respectively.
JP569778A 1978-01-20 1978-01-20 Production of gypsum fine powder Granted JPS5499099A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP569778A JPS5499099A (en) 1978-01-20 1978-01-20 Production of gypsum fine powder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP569778A JPS5499099A (en) 1978-01-20 1978-01-20 Production of gypsum fine powder

Publications (2)

Publication Number Publication Date
JPS5499099A true JPS5499099A (en) 1979-08-04
JPS6232131B2 JPS6232131B2 (en) 1987-07-13

Family

ID=11618285

Family Applications (1)

Application Number Title Priority Date Filing Date
JP569778A Granted JPS5499099A (en) 1978-01-20 1978-01-20 Production of gypsum fine powder

Country Status (1)

Country Link
JP (1) JPS5499099A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2629069A1 (en) * 1988-03-24 1989-09-29 Lafarge Sa Platres PROCESS FOR THE PREPARATION OF CALCIUM SULFATE HAVING A LONGILINE CRYSTALLINE STRUCTURE WITH A MASTERIZED LENGTH AND FORM FACTOR
FR2640961A1 (en) * 1988-12-22 1990-06-29 Lafarge Platres

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5240494A (en) * 1975-09-29 1977-03-29 Onoda Cement Co Ltd Process for producing needle crystal fiber of gypsum

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5240494A (en) * 1975-09-29 1977-03-29 Onoda Cement Co Ltd Process for producing needle crystal fiber of gypsum

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2629069A1 (en) * 1988-03-24 1989-09-29 Lafarge Sa Platres PROCESS FOR THE PREPARATION OF CALCIUM SULFATE HAVING A LONGILINE CRYSTALLINE STRUCTURE WITH A MASTERIZED LENGTH AND FORM FACTOR
FR2640961A1 (en) * 1988-12-22 1990-06-29 Lafarge Platres

Also Published As

Publication number Publication date
JPS6232131B2 (en) 1987-07-13

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