Other

Vsesojuzny Nauchno-issledovatelsky I Proektny Institut Aljuminievoi,

Vsesojuzny Nauchno-issledovatelsky I Proektny Institut Aljuminievo

Leningradsky Tekhnologichesky Institut Imeni Lensoveta

Nikolai A Kaluzhsky

Ivan M Kostin

Isaak A Zatulovsky

Alexei I Alexeev

Viktor M Sizyakov

Vladimir Nikolaevich Kostin

Gakif Zakirovich Nasyrov

Nikolai S Shmorgunenko

Khoren A Badaliants

Igor K Tsybukov

Vladimir P Nikiforov

Valentin I Korneev

Vladimir V Andreev

Nikolai Ivanovich Eremin

Svetozar V Evdokimov

Evgeny A Isakov

Mikhail Ivanovich Zaitsev

Pavel S Vladimirov

Ilya G Kil

Semen Alexandrovich Tager

Alexandr N Smorodinov

Boris Alexandrovich Stolyar

Dinam Latypovich Nasyrov

Vasily I Nosikov

Lev Nikolaevich Bobkov

Ljudmila Nikolaevna Abramova

Semen E Gefter

Valery P Lankin

Garry Vladimirovich Telyatnikov

Abram Zinovievich Jurovsky

Alexei S Derkach

Grigory E Volfson

German Abramovich Kaim

Vladimir Ivanovich Tarasov

Mikhail Yakovlevich Shpirt

Zarya N Alexandrova

Anatoly M Tsyplakov

Viktor Mikhailovich Kozlov

Boris P Velichko

Viktor Prokhorovich Lyakhov

Albert A Kostin

Fritiof Meerovich Yakhilevich

Alexandr G Zhukov

Valentin N Afanasiev

Vladlen Iosifovich Panin

Faitel Markovich Rubinchik

Viktor S Kutsenko

Evgenia S Ostrovlyanchik

Khoren A Badaiants

Galina M Vysotskaya

Vitaly Mikhailovich Averin

Vladislav Mikhailovich Denisov

Leonid I Finkelshtein, Deceased

Vinetsy I Chernov

Evgeny I Mironov

Julia L Finkelshtein, Administrator

Muzafar Suleiman-ogly Tagiev

Nina J Finkelshtein, Administrator

Boris A Kuzmin

Savely Mikhailovich Milrud

Vladimir Ivanovich Lagno

Mikhail V Yazev

Vladislav A Krochevsky

The cement of the invention comprises chemically combined oxides, percent by mass: CaO, 50 to 60; Al.sub.2 O.sub.3, 28 to 37; Fe.sub.2 O.sub.3, 0.01 to 1; SiO.sub.2, 0.1 to 8; Na.sub.2 O, 0.1 to 1; K.sub.2 O, 0.1 to 0.5; H.sub.2 O, 3 to 12; and incorporates 85 to 99% by mass of a fraction with a particle size of below 80 .mu.m and 1 to 15% by mass of a fraction with a particle size of from 80 to 200 .mu.m. The cement can also contain one or more additives: calcium oxide or calcium hydroxide, calcium carbonate, calcium carboaluminate. The method according to the invention for preparing said cement comprises a heat-treatment of calcium hydroalumosilicate containing SiO.sub.2 in an amount of not more than 8% by mass at a temperature of from 250.degree. to 600.degree. C. The heat-treated product is disintegrated to produce 85 to 99% by mass of a fraction with a particle size of below 80 .mu.m and 1 to 15% of a fraction with a particle size of from 80 to 200 .mu.m. During the heat-treatment of the hydroalumosilicate at least one component can be added calcium oxide or calcium hydroxide, calcium carbonate, calcium carboaluminate. The cement is useful in foundry engineering for the manufacture of articles from ferrous and non-ferrous metals.

Cement for the manufacture of cores and moulds and method for preparing

The process consists of two desilication stages. In the first stage the aluminate liquor resulting from digestion of the sinter is subjected to an autoclave treatment to remove the major portion of impurities of SiO.sub.2 and Fe.sub.2 O.sub.3. In the second stage the aluminate liquor is treated with a desilication agent comprising a lime pulp containing oxides CaO, Al.sub.2 O.sub.3, SiO.sub.2, Fe.sub.2 O.sub.3, Na.sub.2 O in a mass ratio of CaO:(SiO.sub.2 +Fe.sub.2 O.sub.3)=1,000 to 5,000:1 and Na.sub.2 Al.sub.2 O.sub.3 =0.25-0.60:1, wherein CaO is active, Na.sub.2 O--in the carbonate form. This lime pulp is employed in such an amount as to ensure the content of active CaO in the aluminate liquor within the range of from 5 to 10 g/l . The impurities of SiO.sub.2 and Fe.sub.2 O.sub.3 present in the liquor pass into the solid phase with the formation of calcium hydrogarnets of the formula 3 CaO(Al,Fe).sub.2 O.sub.3 mSiO.sub.2 (6-2m)H.sub.2 O, wherein m=0.01-0.5 which are separated as a mud.

Process for desilication of aluminate liquors in the production of

The present invention relates to the production of alumina and, more specifically, to a process for desilication of aluminate solutions. The process of desilication according to the present invention comprises treatment of the aluminate solution first with a calcium-containing reagent 'a' which is a product of the reaction of desilication of the aluminate solution; reagent 'a' contains mainly calcium hydrogarnet of the formula:

Process for desilication of aluminate solution

Disclosed is a system of current-supply buses for aluminum-producing electrolyzers arranged transversely in a row and spaced from each other. The system comprises cathode stacks, anode risers installed in the spaces provided between the electrolyzers, and anode buses for supplying current from the anode risers to electrolyzer anode systems shaped as parallelograms. At least two of the anode risers of each electrolyzer are arranged past the planes passing through the end edges or borders of the anode systems. The proportion of the anode risers so arranged is determined such as to ensure the symmetric distribution of the magnetic field intensity components.

System of current supply buses for aluminum-producing electrolyzers

A dual current supply system for aluminum-producing electrolyzers longitudinally arranged in a series-connected row comprises at least four anode risers in each space between next-adjacent electrolyzers. The system includes anode systems and anode buses electrically connected to the anode risers for supplying current from the anode risers to the anode systems. Two of the anode risers of one of a pair of next-adjacent electrolyzers are coaxially positioned in the space between the next-adjacent electrolyzers and two of the anode risers of the other of the pair of next-adjacent electrolyzers are positioned in the space between the next-adjacent electrolyzers in coplanar relation with the anode risers of the one of the next-adjacent electrolyzers. The arrangement of the anode risers enables a more uniform distribution of the magnetic field and permits the total length of the electrolyzer body and current supply buses to be reduced.

Dual current supply system for aluminum-producing electrolyzers

The invention relates to a process for the production of alumina from mineral component of solid fuels containing aluminum, silicon and iron oxides. The process comprises burning a mixture of a solid fuel with limestone in the following molar ratios of limestone to said oxides: CaO:SiO.sub.2 =2.0, CaO:Al.sub.2 O.sub.3 =1.3-1.8, CaO:Fe.sub.2 O.sub.3 =1.0, at 1700.degree.-1900.degree. C. As a result, a melt is obtained containing calcium compounds: 2CaO.SiO.sub.2, 12CaO.7Al.sub.2 O.sub.3, CaO.Al.sub.2 O.sub.3, CaO.Fe.sub.2 O.sub.3. The melt is cooled and leached with soda solutions for extracting alumina. The sludge remaining after the leaching is suitable for Portland cement production. The invention enables a considerable enlargement of the range of starting products for aluminum and cement industries due to the use of the mineral component of solid fuels, an about twofold reduction of capital investments in the alumina production and reduction of the fuel consumption by 30-40%.

Process for the production of alumina from the mineral component of

A plant, comprising apparatus for sequential fluidized bed roasting, reducing and cooling of powdered alunite, mounted on a support and communicating with devices for supplying gas into each apparatus and with cyclones for trapping powdered alunite from flue gases and returning it into said apparatus. According to the invention, built-in the plant in front of the apparatus for roasting alunite, is a shaft heat exchanger having at least one throat subdividing its interior in height into a top and bottom chamber with the ratio of the passage cross-sectional areas of the wide and narrow parts falling within a range of from 2 to 12. The top chamber of the shaft heat exchanger communicates with a cyclone heat exchanger via a supply pipe to which is connected an initial alunite feeder and a cyclone, the bottom chamber of the shaft heat exchanger being in communication with a means for producing flue gases and a pipe discharging gas from the apparatus for reducing alunite though a cyclone. The plant may comprise the second heat exchanger built-in intermediate of the apparatus for roasting and that for reducing alunite. As compared with the known similar plants, the plant, according to the invention, provides for the production of alunite featuring a higher quality and at much lower expenditures.

Plant for fluidized bed heat treatment of powdered alunite

The specific feature of the present method is that in the process solution resulting in the processing of alunite with the object of producing alumina and potassium sulphate therefrom, an excess amount of sodium ions is maintained with respect to the potassium ions. The method is advantageous in that it ensures a higher yield of potassium sulphate and a lower contamination of the final products with respect to sodium and potassium ions.

Method of producing alumina and potassium sulphate form alunite

Growing community of inventors

Saint-Petersburg, Russia

Nikolai A Kaluzhsky