JPS55162427A - Manufacture of alpha-type hemihydrate gypsum - Google Patents

Manufacture of alpha-type hemihydrate gypsum

Info

Publication number
JPS55162427A
JPS55162427A JP7138279A JP7138279A JPS55162427A JP S55162427 A JPS55162427 A JP S55162427A JP 7138279 A JP7138279 A JP 7138279A JP 7138279 A JP7138279 A JP 7138279A JP S55162427 A JPS55162427 A JP S55162427A
Authority
JP
Japan
Prior art keywords
gypsum
type hemihydrate
hemihydrate gypsum
under pressure
slurry
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.)
Pending
Application number
JP7138279A
Other languages
Japanese (ja)
Inventor
Takao Hishinuma
Sadao Takahashi
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.)
Mitsubishi Power Ltd
Original Assignee
Babcock Hitachi KK
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 Babcock Hitachi KK filed Critical Babcock Hitachi KK
Priority to JP7138279A priority Critical patent/JPS55162427A/en
Publication of JPS55162427A publication Critical patent/JPS55162427A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C01F11/46—Sulfates
    • C01F11/466—Conversion of one form of calcium sulfate to another

Abstract

PURPOSE: To form α-type hemihydrate gypsum having high hydration solidifying strength without exerting a harmful influence upon waste water treatment, etc. by adding α-type hemihydrate gypsum particles as seed crystals manufactured by other method to a gypsum slurry followed by hydrothermal treatment under pressure.
CONSTITUTION: To a gypsum slurry as starting material are added seed crystals manufactured by adding an org. carboxylic acid salt such as sodium citrate as a habit modifier to gypsum followed by hydrothermal treatment under pressure. The slurry is then hydrothermally treated while agitating under pressure and predetermined conditions to crystallize α-type hemihydrate gypsum. By this method the absolute quantity of the habit modifier contained in waste water discharged from the process can be reduced, so the quantity of the constituents of COD, BOD, etc. is reduced.
COPYRIGHT: (C)1980,JPO&Japio
JP7138279A 1979-06-07 1979-06-07 Manufacture of alpha-type hemihydrate gypsum Pending JPS55162427A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7138279A JPS55162427A (en) 1979-06-07 1979-06-07 Manufacture of alpha-type hemihydrate gypsum

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7138279A JPS55162427A (en) 1979-06-07 1979-06-07 Manufacture of alpha-type hemihydrate gypsum

Publications (1)

Publication Number Publication Date
JPS55162427A true JPS55162427A (en) 1980-12-17

Family

ID=13458890

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7138279A Pending JPS55162427A (en) 1979-06-07 1979-06-07 Manufacture of alpha-type hemihydrate gypsum

Country Status (1)

Country Link
JP (1) JPS55162427A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010013304A (en) * 2008-07-02 2010-01-21 Tokuyama Corp Method for regenerating gypsum from gypsum board waste material
JP2012131704A (en) * 2012-02-17 2012-07-12 Tokuyama Corp Method for recycling gypsum from gypsum board scrap material

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010013304A (en) * 2008-07-02 2010-01-21 Tokuyama Corp Method for regenerating gypsum from gypsum board waste material
JP2012131704A (en) * 2012-02-17 2012-07-12 Tokuyama Corp Method for recycling gypsum from gypsum board scrap material

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