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112 条记录 (耗时 0.012 秒)

    Ozone whitening of synthetic gypsum
    51.
    发明授权
    Ozone whitening of synthetic gypsum 失效
    合成石膏的臭氧增白

    公开(公告)号：US4344925A

    公开(公告)日：1982-08-17

    申请号：US225232

    申请日：1981-01-15

    申请人： Philippe Pichat ,  Robert Sinn ,  Michel Neil

    发明人： Philippe Pichat ,  Robert Sinn ,  Michel Neil

    IPC分类号： C01F11/46 ,  C04B11/00 ,  C04B11/02

    CPC分类号： C01F11/468

    摘要： A process for the whitening of phosphogypsum comprising treating a phosphogypsum in aqueous suspension with an amount of ozone equal to at least 150 parts by weight per million parts by weight of phosphogypsum calculated as Ca SO.sub.4.2H.sub.2 O, the pH of the aqueous suspension being lower than or equal to 3, to yield a whiteness grade of phosphogypsum higher than 75, according to French Standard NF Q 03-038.

    摘要翻译： 一种磷石膏增白的方法，包括用臭氧量等于至少150重量份/百万重量份以CaSO 4·2H 2 O计算的磷石膏处理含水悬浮液中的磷石膏，水悬浮液的pH低于 或等于3，以产生高于75的磷石膏的白度等级，根据法国标准NF Q 03-038。

    Manufacture of calcium sulphate alpha hemihydrate
    52.
    发明授权
    Manufacture of calcium sulphate alpha hemihydrate 失效
    硫酸钙α半水合物的制造

    公开(公告)号：US4120737A

    公开(公告)日：1978-10-17

    申请号：US570946

    申请日：1975-04-22

    申请人： John Sorbie Berrie ,  Graham Edward Woolley

    发明人： John Sorbie Berrie ,  Graham Edward Woolley

    IPC分类号： C04B11/02 ,  C01F11/46 ,  C04B11/00

    CPC分类号： C01F11/46 ,  C04B11/00

    摘要： A process for the manufacture of calcium sulphate alpha-hemihydrate which comprises the step of interacting an aqueous solution of calcium chloride and a source of sulphate or bisulphate ions in an aqueous system at a temperature above the calcium sulphate hemihydrate/gypsum transition temperature under the reaction conditions. The preferred reagents are the waste calcium chloride/sodium chloride effluent of the ammonia soda process and sulphuric acid (e.g. impure sulphuric acid effluent) to give hydrochloric acid as a co-product. The preferred reaction temperature is at least 20.degree. C. above the transition temperature (about 70.degree. C), e.g. at 95.degree.-100.degree. C at atmospheric pressure.

    摘要翻译： 一种制造硫酸钙α半水合物的方法，其包括在反应中在高于硫酸钙半水合物/石膏转变温度的温度下在水性体系中将氯化钙水溶液和硫酸盐或硫酸氢根离子相互作用的步骤 条件。 优选的试剂是氨苏打方法的废氯化钙/氯化钠流出物和硫酸（例如不纯的硫酸流出物），以产生作为副产物的盐酸。 优选的反应温度在转变温度（约70℃）以上至少20℃，例如 在95°-100℃的大气压下。

    Apparatus for treating by-product gypsum to be used as an inhibitor for setting of cement
    53.
    发明授权
    Apparatus for treating by-product gypsum to be used as an inhibitor for setting of cement 失效
    用于处理副产物石膏作为凝结水泥的抑制剂的装置

    公开(公告)号：US3998596A

    公开(公告)日：1976-12-21

    申请号：US602927

    申请日：1975-08-08

    申请人： Yoshiharu Fukuda ,  Toshio Onishi ,  Akitoshi Takeuchi

    发明人： Yoshiharu Fukuda ,  Toshio Onishi ,  Akitoshi Takeuchi

    IPC分类号： C01F11/46 ,  C04B11/26 ,  C04B22/14 ,  B01J1/00 ,  C04B11/02

    CPC分类号： C04B11/26 ,  C01F11/46 ,  C04B22/144

    摘要： Apparatus comprising means for dispersing comminuted limestone in a stream of hot gas and calcining it to form quicklime; a calcining chamber into which comminuted gypsum and the stream of hot gas containing the quicklime are introduced wherein the gypsum is calcined and thoroughly mixed with the quicklime; a gas-solids separator for separating the calcined gypsum and quicklime from the gas stream; and hydration means for hydrating the quicklime and gypsum whereby any phosphoric acid in the gypsum reacts with the hydrated quicklime to form insoluble calcium phosphate.

    摘要翻译： 装置包括用于将粉碎的石灰石分散在热气流中并煅烧以形成生石灰的装置; 煅烧室，其中引入粉碎的石膏和含有生石灰的热气流，其中将石膏煅烧并与生石灰充分混合; 用于将煅烧石膏和生石灰与气流分离的气固分离器; 以及用于水化生石灰和石膏的水合方法，其中石膏中的任何磷酸与水合生石灰反应形成不溶性磷酸钙。

    Method for the preparation of fibrous calcium sulfate hemihydrate
    54.
    发明授权
    Method for the preparation of fibrous calcium sulfate hemihydrate 失效
    制备纤维状硫酸钙半水合物的方法

    公开(公告)号：US3977890A

    公开(公告)日：1976-08-31

    申请号：US494425

    申请日：1974-08-05

    申请人： Karlis L. Jaunarajs ,  Julie C. Yang

    发明人： Karlis L. Jaunarajs ,  Julie C. Yang

    IPC分类号： C04B11/02 ,  C04B11/00

    CPC分类号： C04B11/02

    摘要： A process is described for the formation of fibrous calcium sulfate hemihydrate, the fibers thereof having specified dimensions, wherein a dilute aqueous suspension of gypsum and, if desired, a crystal habit modifier is first formed. The gypsum in the suspension is then converted into fibrous hemihydrate by reaction in the presence of saturated steam at 120.degree. to 155.degree.C for 0.5 to 2.5 hours.

    摘要翻译： 描述了形成纤维状硫酸钙半水合物的方法，其纤维具有规定的尺寸，其中首先形成石膏的稀释水性悬浮液和如果需要的话，结晶习性调节剂。 然后将悬浮液中的石膏在120-155℃的饱和蒸汽存在下反应0.5至2.5小时，将其转化为纤维状半水合物。

    Method for the production of synthetic calcium sulfate hemihydrate
    56.
    发明授权
    Method for the production of synthetic calcium sulfate hemihydrate 失效
    合成硫酸氢钙的生产方法

    公开(公告)号：US3574648A

    公开(公告)日：1971-04-13

    申请号：US3574648D

    申请日：1967-12-18

    申请人： KNAUF WESTDEUTSCHE GIPS

    发明人： WIRSCHING FRANZ ,  WANDSER BRUNO ,  KNAUF KARL

    IPC分类号： C04B11/26 ,  C04B11/02 ,  C04B11/08

    CPC分类号： C04B11/26

    摘要： BY-PRODUCT GYPSUM ARISING IN THE EXTRACTION OF PHOSPHORUS-CONTAINING MINERALS AND CONTAMINATED WITH PHOSPHORIC ACID AND ITS WATER-SOLUBLE SALTS IS CALCINED, THE CALCINE IS TREATED WITH WATER AND A NEUTRALISING AGENT TO FORM CALCIUM SULFATE DIHYDRATE AND WATER-INSOLUBLE COMPOUNDS OF THE CONTAMINANTS AND THE DIHYDRATE IS SUBJECTED TO A SECOND CALCINATION TO PRODUCE A SYNTHETIC CALCIUM SULFATE HEMIHYDRATE WHICH HAS PROPERTIES COMPARABLE TO OR BETTER THAN THOSE OF PLASTER OF PARIS DERIVED FROM NATURAL GYPSUM.