BALANCE MODELING OF THE PROCESS FOR SiCaV ALLOY PRODUCING FROM WASTE VANADIUM CATALYST

Transcription

1 etar etrov, Journal aksi of Cheical arinov, Technology laen Todorov, and etallurgy, Radost Alexandrova, 49,, 04, Rossitsa 49-9 aunova BAANCE DEIN F THE RCE FR icav AY RDUCIN FR WATE VANADIU CATAYT etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova Departent of Ferrous etallurgy and etal Foundry, University of Cheical Technology and etallurgy 8 Kl. hridski, 76 ofia, Bulgaria E-ail: pbpetrov@uct.edu Received 0 July 0 Accepted 0 Noveber 0 ABTRACT The odern steel industry is characterized by continual iproving the quality of the produced steel with constantly increasing range and quantity of deoxidation and alloying alloys. Aong the falls ica with vanadiu. Consider the absence in the Republic of Bulgaria of raw aterials containing vanadiu for exaple, the needs of etallurgy are provided ainly by iports of ferro-alloys. At the sae tie our country has an active cheical and etallurgical industries where significant polluting quantities of vanadiu catalyst drop fro production of sulfuric acid, which contains i and V. Both aterial and heat balance odels are developed for carbotheral producing of ica with a high content of vanadiu. Vanadiu waste, etallurgical lie and etallurgical are the raw aterial. The eleents in the alloy after the carbotheral reduction are: V 9.09 %, Fe 9.06 %, i 66.4 %, Ca.6 %, 0.0 %, 0.04 %, C 0. %, Al.8 % и n 0.0 %. The ain contributor into the alloy of V, i and Fe is the waste vanadiu catalyst. The relative consuption of electricity according to the heat balance odel is 0 kwh/ton alloy. Keywords: vanadiu catalyst, lie,, ica alloy. INTRDUCTIN ica is used for odification and deoxidation of iron, steel and alloys. In separate studies it was prepared ica with the eleents vanadiu, zirconiu, titaniu, aluinu and others [ - ]. When alloying ica with vanadiu and subsequent alloying of the steel, its strength at reduced teperatures increases without reducing the ipact toughness. Currently, ica is produced ainly in the Russian Federation in accordance with the requireents of T [6]. The purpose of this study is to ake aterial and heat balance odel for producing ica alloy with higher content of vanadiu using vanadiu waste, lie and etallurgical. THERETICA CNIDERATIN AND REUT A aterial balance odel of carbotheral producing ica with increased content of vanadiu fro vanadiu waste. The coposition of the charge aterials is given in the Table.. ain raw aterial for the alloy is a waste vanadiu catalyst [6, 7] and secondary the etallurgical lie. etallurgical is used as a reducer. According to [7-0]: 98 % of V is reduced and V passes into the alloy, % non-reduced V goes into the slag, and % non-reduced V - in the gas phase; Fe is reduced % to Fe, and then passes in the alloy, 88 % of n is reduced by the carbon fro the coal, and 6 % of the resultant n passes into the gas phase and 49

2 Journal of Cheical Technology and etallurgy, 49,, 04 Table. Cheical coposition of the charge aterials. Charge aterials Cheical coposition, % V Fe i Al Na n Ca Р О К О C Vol..V catalyst 4,8,98 66,68 0,96 4, ,8 -, -. et. lie , ,00. Coke -,0 7,7,0-0,0 0,40 0,04-8,4 0,, 7 % - in the alloy. The reaining % non-reduced n passes in the slag; Al of 90 % reduced Al passes in the alloy, the non-reduced Al is 0 % and it goes into the slag; 90 % of i is reduced and i goes to the alloy. 6 % of i is reduced to i, passing into the gas phase, and 4 % of i is not reduced at all and goes into the slag. art of the i alloy joins 99.9 % of the sulfur fro the vanadiu catalyst and % of the sulfur fro the and pass into the gas phase; Ca fro the is reduced 8 %, and passes into the etal. In the slag passes % non-reduced Ca; fro the is reduced %, and 0 % fro the obtained goes into the etal and 0 % - in the gas phase, Na and K are not reduced, and 9 % of the pass into the gas phase while the rest % - in the slag; the volatile coponents pass % in the gas phase; in the alloy up to 0.0 % of its coposition; in the alloy up to 0.0 %; the aount of carbon oxidized % passes into the gas phase; 0. % of the alloy is saturated with carbon during reduction process. Calciu in alloy - %. The calculations are ade on the basis of.00 kg of vanadiu catalyst. The following rounded atoic (A) and olecular () asses are used Ac -, AV V -, A Fe - 6, Ai- 8, A \ - 6; A n - ; A - ; A - ; A Al - 7; A Ca - 40; V - 8, Fe - 60, - 4, i - 60; - 0; - 6; - 6. Al n Ca. Aount of oxygen taken away The aount of oxygen abstracted by reduction is calculated by the forula: %. η R, kg () where: is the aount of oxygen released fro an oxide of vanadiu catalyst at the reduction, kg; % - participation rate of the oxide in the vanadiu catalyst, %; - aount of vanadiu catalyst -, kg; - coefficient of transition fro rate per kilogra; η R - reduction factor of the oxide to the eleent R, passing in the alloy; - olecular weight of the oxygen fro corresponding oxide ; - olecular weight of corresponding oxide. Then: V V + i i + V i i,07 kg., kg. Fe Fe + Al Al + Fe Al,9 kg. 0,4 kg. i i + i,0 kg. i i + i i, kg. Al Al + Al 0,4 kg. The aount of is deterined by the equation: V Fe , kg () i i i Al r 7,8 kg. Quantity of the reducer to connect the oxygen fro the oxides of vanadiu catalyst The aount of reducer is deterined according to:., kg () C C r C where: r is the aount of reducing agent for the oxides of vanadiu catalyst, kg; - olecular ass 0

3 etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova of oxygen fro foration of the olecule of C; C - olecular ass of a carbon fro foration of the olecule of C. To connect by the reaction C + C is needed C: r 8,6 kg. For connecting kg О in reaction C + C is required C according:., kg, C C r C (6). Quantity of fro oxides of and deterining the aount of C to reduce the At the reduction a part of the carbon is consued for reduction of the oxides of the. Its aount is calculated after deterining the aount of oxygen in these oxides. The calculation is for kg of. Then is calculated a predeterined aount of for reduction of the oxides of vanadiu catalyst and (a ash): %. η R, kg, (4) where: is the aount of oxygen released fro oxide by reduction of, kg; % - participation rate of the corresponding oxide in the, %; - quantity of the -, kg. Then: Fe Fe + Fe 0, kg. i i +,49 kg. i i i + 0, kg. i i Al Al + 0,9 kg. Al The aount of is: n n + n 0,0 kg. Ca Ca + 0,0 kg. Ca + 0,0 kg , kg. Fe i i i Al n Ca () r, kg. 4. Quantity of reducer to connect the oxygen fro the oxides of the where: r is the aount of reducing agent for the oxides of the vanadiu catalyst, kg; - olecular ass of oxygen for foration of the olecule C; C - olecular weight of carbon for foration of the olecule C. r r,84 kg C for the reduction of the oxides of kg fro, representing r %.. Calculation of advance aounts of r., kg. (7) %C - кокс where: is the quantity of for reduction of oxides of catalyst and, kg; - coefficient of transition fro rate per kilogra; % C - participation rate of carbon in the. r 4,7 kg. 6. Calculation of the quantity alloy The aount of the resulting pure eleent in the reduction of the corresponding oxide was calculated by the forula: %. η R e e + (8) %. η R e +, kg, where: is the quantity of pure single eleent in the e alloy by oxide reduction, kg; e - olecular ass of the eleent fro the corresponding oxide. Then: V V + V,64 kg. Fe Fe + Fe,6 kg. i i + 9,07 kg. i r Al Al + Al 0,8 kg. Ca Ca + 0,09 kg. Ca n n + rovided by, 7 % fro n fro 88 % of the reduced n passes into the alloy.

4 Journal of Cheical Technology and etallurgy, 49,, 04 Then: ηn n n., kg. r n 0,0 kg. + (9) rovided by, 0 % fro fro % of the reduced passes into the alloy. Then: r η., kg. 0,00 kg. Aggregate pre-aount alloy: V Fe i Al + + +, kg. n Ca r,7 kg. (0) () 99.9 % of the sulfur fro the vanadiu catalyst and % of the sulfur fro the is associated with the silicon fro alloy and passes into the gas phase according to the relation: %. η () %. η +, kg, where: is the ass of sulfur passing into the gas phase, kg; % - participation rate of sulfur in the vanadiu catalyst, kg; % - participation rate of sulfur in the, kg; η - coefficient of the transfer of fro vanadiu catalyst and in to gas phase, %. r,8 kg for binding with i. Then, according to the equation i + follows that:., kg, i i () where: is the olecular ass of the sulfur fro ; i - olecular ass of silicon fro. r 9,78 kg i. Then in the alloy will reain: i -, kg (4) i i i r 9,9 kg. i Interediate ass of the alloy is: -, kg () i i i 0,0% reain in the coposition of the alloy. r in the alloy would be:, kg, (6) η where: η is the coefficient of passage of the sulfur in the alloy. r 0,0 kg. The aount of the alloy becoes: +, kg. (7) r,0 kg. Ca in the alloy should be %. ther eleents represent 88 %. But kg alloy containing kg Ca Ca fro etallurgical. The necessary additional aount of Ca alloy is: - Ca Ca, kg. 88 (8) r,47 kg. Ca The Ca is provided by adding of Ca in aount:. kg (9) Ca Ca Ca Ca Ca where: Ca is the olecular ass of Ca; Ca Ca - olecular ass of Ca fro Ca. r Ca 4,86 kg Ca secured by etallurgical lie, consisting of 99 % Ca (% Ca lie ). r the required aount of lie is: Ca lie, kg. (0) lie % Ca or 99 4,9 kg lie 4,86 For reduction of Ca fro the lie, additional quantity of further is introduced in the syste. In order to deterine its quantity it is necessary to calculate first the aount of oxygen by reduction of Ca, which is released by the reaction Ca Ca + Ca and represents: Ca Ca., kg () Ca

5 etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova Ca r,9 kg. For connecting of Ca carbon is needed according to reaction С + О СО and forula: C Ca C r., kg C () r r,04 kg. The ass of the alloy becoes: 4 + Ca, kg () r 4 8,97 kg. For carburization - 0,% C. r C in the alloy would be: C 4 ηc, kg (4) where: η - ratio of transition of C in the alloy, %. r C 0,06 kg. C Final ass of the alloy: 4 + C, kg. () r 9,0 kg. 7. Final aount of The aount of required for carburization of the alloy and the aount of to provide carbon for reduction of the additional quantity introduced by the etallurgical lie Ca is: ( C + r ).,kg % C - (6) r, kg. The quantity of the needed is: +, kg. (7) r 6,0 kg. Taking into account the setaside of the of % in the process, the final aount of the etallurgical becoes: 4,kg (8) 88 r r 4 4,0 kg. The coposition of the charge and cheical coposition of the alloy are shown in Table. 8. Quantity and cheical coposition of the slag The aount of the corresponding oxide passing in the slag is given by: e %. η + %. η +, kg (9) where: is the aount oxide passing into the slag, e kg; η - coefficient of passage of oxide in the slag. Then: % of V passes into the slag. This represents the aount of: 0,0 kg. V 4 % of i passes into the slag. This represents the aount of:,77 kg. i % of Ca passes into the slag. This represents the aount of: 0,0 kg Ca 0 % of Al passes into the slag. This represents the aount of: 0,8 kg. Al % of Na passes into the slag. This represents the aount of: 0, kg. Na % of K passes into the slag. This represents the aount of: 0,9 kg. K Table. Coposition of the charge aterials and cheical coposition of the alloy. aterial kg % Alloy kg % V catalyst,00 70,9 V,64 9,09 Coke 6,0,60 Fe,6 9,06 ie 4,9,48 i 9,9 66,4 Al 0,8,8 n 0,0 0,0 Ca,6,6 0,00 0,0 0,0 0,04 C 0,06 0, Total 4,0,00 Total 9,0,00

6 Journal of Cheical Technology and etallurgy, 49,, 04 Table. Cheical coposition of the slag. The total aount of the coponents in the slag is: + + V i Ca + + +, kg Al Na K (0) r,64 kg. The cheical coposition of the slag is shown in Table. 9. Quantity and cheical coposition of the gas phase of the oxides of vanadiu catalyst, - Ca of oxides of etallurgical and fro the reduction of Ca is associated with the C in the reaction C + C., kg () where: - oxygen, separated fro the oxides of the ashes of required for the reduction in the aount. r,8 kg The total aount of C is: ( + + )., kg () Ca C C C C r 7,84 kg. СО 99.9 % of the sulfur fro the vanadiu catalyst, and % of the sulfur fro the is associated with i fro alloy and pass into the gas phase by the equation i +. According to (): %. η %. η. +. kg, follow that:,8 kg for connecting with i. Then: xides kg % V 0,0,7 i,77 76,0 Al 0,8 4,9 Ca 0,0 0, Na 0, 6, K 0,9 0,7 Total,64,00., kg. () r 0,96 kg. The etallurgical and lie contain volatile coponents (VC) in aount of % VC lie and % VC respectively which also go % in the gas phase in an aount of: lie lie %VC. VC lie, kg (4) where: %VC lie is the participation rates of VC in the lie, %; - coefficient of transition fro rate per kilogra. r 0,0 kg and vc lie %VC. VC,kg () where: % VC is the participation rates of VC in the, %; - coefficient of transition fro rate per kilogra. r,0 kg. vc The aount of other oxides, passing in the gas phase was calculated by the forula: %. η + %. η +, kg (6) where: is the quantity of oxide passing in the gas phase, kg; η - coefficient of transition of oxide in the gas phase. Then: % of V passes into the gas phase. This represents the aount of V 0,0 kg. 6% of i passes into the gas phase as i. This represents the following aount: i i 4,6 kg, and the oxygen by reaction i i + is: + i i+ / i i +,6 kg i i (7) Then: i i + / i i i -, kg (8) where: is the i quantity of i passing in gas i phase, kg. r,80 kg. i 6 % n (η n ) fro 88 % reduced n passes into the gas phase. This represents the following aount: ηn n n., kg (9) 4

7 etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova r 0,00 kg. n 6 % (η ) fro % reduced passes into the gas phase. This represents the following aount: η., kg. (40) r 0,00 kg. 9 % of Na passes into the gas phase. This represents the following aount: 4,6 kg. Na 9 % of K passes into the gas phase. This represents the following aount: 7,44 kg. K The total aount of the coponents in the gas phase is: C + + vclie vc V i n + + +, kg Na K r 07,7 kg. The cheical coposition of the gas phase is given in Table 4. uary of the aterial balance of the process of carbotheral producing of ica with increased content of vanadiu is shown in Table. At properly calculated balance ust be fulfilled the following equation:, kg expenditure profit (4) 0. Relative fuel charge aterials Below is presented the relative expenditure of charge aterials to produce one tone of the alloy. The consuption of the charge aterials is calculated according to the relations: 0 ch...0 ch..., kg. (4) where: ch.. 0 is the quantity of a charge aterial coponent for the preparation of an alloy in an aount Table 4. Coposition of the gas phase. xides and eleents kg % СО 7,84 66,70 0,96 9,46 i,80,67 VC-lie 0,0 0,0 VC-,0, V 0,0 0,0 0,00 0,00 n 0,00 0,00 Na 4,6 4,0 K 7,44 6,9 Total 07,7,00 of 0 kg (respectively 0, 0, lie 0 ), kg; ch.. - the quantity of a charge aterial coponent for the preparation of an alloy in an aount (respectively, 4, lie ), kg; 0-0 kg of the alloy tone of the alloy. r 0 444,7 kg; 0 4,0 kg; lie 0 69,4 kg. The aount of the charge aterials to receive a ton of the alloy is: ch lie, kg. (44) r Σ ch ,87 kg. This yields to: V catalyst 444,7 kg/t alloy (68,%), etallurgical 4,0 kg/t alloy (8,%), lie 69,4 kg/t alloy (,7%). A heat balance odel of carbotheral production of ica with increased content of vanadiu fro vanadiu waste. Incoe of heat.. A heat fro oxidation of carbon. It is calculated according to the reaction C + C and dependence: Q a C. D H C, kj (4) where: t H C is the enthalpy of foration of C 90 kj/kg C; C - ass of C necessary for reduction of the Table. aterial balance of the process. Expenditure rofit Raw aterials kg % roducts kg % V catalyst,00 70,9 Alloy 9,0 0,9 etallurgical 6,0,60 lag,64,8 ie 4,9,48 as phase 07,7 76,9 (rounding error) 0,6 0,4 Total (Σ exp ) 4,0,00 Total (Σ pr ) 4,0,00

8 Journal of Cheical Technology and etallurgy, 49,, 04 corresponding oxide, kg. Then: V a) fro V : C + C V,07 kg; C,07., kg 6 Q 444 kj. Fe b) fro Fe : C + C Fe, kg; C,.,4 kg 6 Q 060 kj. i c) fro i : C + C i,0 kg; C,0. 6,6 kg 6 Q 4769 kj. i d) fro i: C + C i,6 kg; C,6.,77 kg 6 Q 6466 kj. 4 Al e) fro Al : C + C Al,4 kg; C 0,4.,4 kg 6 Q 466 kj. n f) fro n: C + C n 0,0 kg; C 0,0. 0,0 kg 6 Q 40 kj. 6 Ca g) fro Ca: C + C Ca,49 kg; C,49., kg 6 Q 096 kj. 7 h) fro : C + C 0,0 kg; C 0,0. 0,0 kg 6 Q 40 kj 8.. A heat fro foration of Ca.i Calculated according to: Q b Ca. DH Ca.i, kj, (46) where: DH is the enthalpy of foration of Ca. Ca.i i 94,6 kj/kg Ca.i ; Ca - ass of Ca, kg. The aount of Ca bonding with i in the slag is 0,0 kg. Then: Q 9 kj... A heat fro the charge aterials The solid charge aterials (vanadiu catalyst, etallurgical and lie) have a teperature of 98 K and then iport physical heat under: lie Q c / 4 /.c i.t, kj (47) where: t is teperature, K; //lie - ass of vanadiu catalyst//lie, kg; c i - specific heat capacity of the coponent of the charge (vanadiu catalyst/ /lie) kj/kg.k. Its value is as follows: for vanadiu catalyst c 0,6 kj/kg.k; for c 0,84 kj/kg.k; for lie с lie 0,80 kj/kg.k. The aount of physical heat introduced into the furnace of vanadiu catalyst, etallurgical and lie would be: Q 7880 kj; Q 068 kj; Q lie 7 kj. Then: Q kj. The total incoe of heat is: Q i Q+ Q + Q + Q4 + Q+ Q6 + Q7 + + Q + Q + Q, kj (48) r Q i 4699 kj.. Expenditure of heat.. Expenditure of heat fro dissociation of oxides. It is calculated by: q %. η R. D He + %. η R +. DH e, kj (49) where: q is the heat of a reaction, kj; % - participation rate of the corresponding oxide in vanadiu catalyst, %; - aount of vanadiu catalyst, kg; % - participation rate of the corresponding oxide in, %; - aount of, kg; - coefficient of transition fro rate to kilogra; η R - coefficient of transition of in the alloy; DН - enthalpy of the respective copound, kj/kg. Then: a) fro V : V V + ; DH 80 kj/kg V ; V 4,7 kg; q 4, kj. b) fro Fe : Fe Fe + ; DH 09,4 kj/kg Fe ; Fe 4,8 kg; q 4,8.09,4 0 kj. 6

9 etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova c) fro i : i i + ; DH 474 kj/kg i ; i 6,7 kg; q kj. d) fro i to i: i i + ; DH 0 kj/kg i ; i 4,6 kg; q 44 kj. 4 e) fro Al : Al Al + ; DH 64 kj/kg Al ; 6 Al,8 kg; q 8 kj. f) fro n: n n + ; DH 784 kj/kg n; n 0,0 kg; q 74 kj. g) fro : + ; DH 067 kj/kg ; 0,0 kg; q kj. h) fro Ca: Ca Ca + ; DH 40 kj/kg Ca; Ca 4,98 kg; q 7096 kj Fro the heat content of the alloy At casting the alloy exports heat as: q Cp..t, kj (0) 9 alloy where: t is teperature of the alloy in casting 60 C; - ass of the alloy 9,0 kg; Cp alloy - specific heat of the alloy 0,789 kj/kg. Then: q 9 74 kj... Fro the heat content of the slag At pouring the slag exports heat as: q Cp t, kj () 0 slag where: t is teperature of the slag in casting 900 C; - ass of slag,64 kg; Cp slag - specific heat of the alloy, kj/kg. Then: q 0 78 kj..4. Fro the heat content of the gas phase as phase exports heat as: q Cp g.f. t, kj () where: t is flue gas teperature 600 C; - ass of the gas phase,4 kg; Cp g.f. specific heat capacity of the gas. For ease of calculation, it is assued that the specific heat capacity of the effluent gases is equal to the specific heat capacity of the carbon oxide - c C, kj/kg. Then: q 76,777 kj... Fro heating and evaporation It is calculated in accordance with (48). а) of Na : Table 6. Heat balance of the process. Incoe Expenditure aterials kj % aterials kj % Fro oxidation of C Fro dissociation of the oxides fro V 444 4, fro V 4009,8 fro Fe 060,0 fro Fe 0,8 fro i ,49 fro i ,8 fro i ,8 fro i to i 44,0 fro Al 466,6 fro Al 8,8 fro n 40 0,04 fro n 74 0,0 fro Ca 096,04 fro 0,0 fro 40 0,04 fro Ca 7096,0 Fro Ca.i 0,0 f heat content: Fro the charge: of the alloy 74,66 fro vanadiu catal. 7880, of the slag 78 0, fro etallurg. 068,0 of the gas phase 76777,4 fro lie 7 0,4 Fro heating and evaporation: of Na 06 0,4 of K 47 0, osses in asonry and throat 89,04 Total 4699 Total 40999,0 hortage

10 Journal of Cheical Technology and etallurgy, 49,, 04 DН 467 kj/kg Na ; Na 4,6 kg; q 06 kj. b) of K : DН 467 kj/kg K ; K 7,44 kg; q 47 kj. The total expenditure of heat is: q q + q + q + q + q + q + e q + q + q + q + q + q + q, kj or q e 6080 kj. () A relative expenditure of electricity: T.E E, kwh, (60) where: T is one ton weight 0 kg; - ass of the alloy (as calculated by the aterial balance), kg. r Е 0 kwh electricity to produce 0 kg alloy. The heat balance of the process of carbotheral production of ica alloy with increased content of vanadiu is suarized in the Table osses in asonry and throat It is assued that the losses in the asonry and the throat of the furnace is % of cuulative heat input. qe or q 4.., kj (4) Then: q 4 89 kj. The total expenditure becoes: q q + q, kj () 8 e e 4 r q e kj. The total quantity of heat of the process is: Q Q - q, kj (6) i e or Q 0689 kj. It is seen fro relation () that the incoe of the heat is not sufficient to cover the heat expenditures. It is therefore necessary to introduce an additional power generation. It is assued that: E Q, (7) where: E is the electricity kwh; Q - heat 600 kj. Then the additional electricity to coplete the process will be: E QΣ, kwh. Q (8) r Е 97 kwh. It is assued that cosφ 0,89. The final expenditure of electricity would be: E E, kwh. cosϕ (9) r E 4 kwh of electricity to obtain of 9,0 kg alloy. To produce of tone alloy is necessary to calculate the relative expenditure of electricity. CNCUIN aterial and heat balance odels for producing ica alloy with high content of vanadiu fro waste vanadiu catalyst, etallurgical and etallurgical lie are developed. The aount of the alloy is estiated as 9,0 kg. The ain eleents in the alloy after reduction are: V -,64 kg (9,09 %); Fe -,6 kg (9,06 %); i - 9,9 kg (66,4 %); Ca -,6 kg (,6 %); n - 0,0 kg (0,0 %); Al - 0,8 kg (,8 %); - 0,00 kg (0,0 %); - 0, 0 kg (0,04 %); C - 0,06 kg (0, %). For reduction with ass 40,96 kg is used. The coponents passed in the slag and gas phase are respectively:,64 kg and 07,7 kg. The predoinant copound in the slag is i, while in the gas phase - C. Rate frequency of the slag is of liited value due to the optiu carbotheral reduction of the coponents of the charge aterials. The estiated shortage of heat is 0689 kj and the energy required to copensate for the lack of heat is 0 kwh for ton alloy. The ica alloy with high content of vanadiu obtained is closed to axiu extent to ica alloy of Russian factory standards TU It is found an effective ethod for utilization of polluting waste product. REFERENCE.. Rais, roduction of Ferroalloys, oskva, etalurgiya, 97, (in Russian).. A. Avraov, etallurgy of the Ferroalloys, ofiya, Tehnika, 988, (in Bulgarian).. V. Ilarionov, Vanadiu Catalysts for roduction of ulphur Acid, oskva, Hiichnai literaturai, 96, (in Russian).

11 etar etrov, aksi arinov, laen Todorov, Radost Alexandrova, Rossitsa aunova 4. C. Winkler, EC Catalyst roducts and Technical ervices Update, roceedings of the ulphur and ulphuric Acid Conference, un City, Republic of outh Africa, 009, asik, V. Ignataiev,. asik, tructure and Quality of Industrials Ferroalloys and odifiers, Kiev, etalurgiya, 97, (in Russian) asik, N. yakishev, B. Elin, Theory and Technology of roduction of Ferroalloys, oskva, etalurgiya, 988, (in Russian). 8.. ikulinskii, rocesses of Electric Theral anufacturing of res, oskva, redne-uralskoe knizhnoe izdatelstvo, 964, (in Russian). 9. I. Frishberg, rocesses of Reduction, Vapour and Condensation in Electric Theral anufacturing of res, verdlovsk, Uralskii rabochii, 969, (in Russian) 0. F. Edneral, A. Filipov, Calculations of teels and Ferroalloys Receiving through Electric etallurgy ethod, oskva, etalurgizdat, 96, (in Russian). 9